Pulp & Paper Canada March/April 2010

March/April 2010

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Capital Expenditures: Federal Money Spurs Spending

EXFOR & Annual Meeting Review Safest Mill Winners Best Picks for the Bio-Economy

JOURNAL OF RECORD, PULP AND PAPER TECHNICAL ASSOCIATION OF CANADA KANG: Low Consistency Refining of Wood Chips

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MARCH/APRIL 2010 Vol. 111, No. 2 A Business Information Group Publication ISSN 0316-4004

FEATURES

8 10 13 18

Safest Mill Contest: Send them home safe, every day Results of Pulp & Paper Canada’s 2009 Safest Mill contest, plus best practices from some of the best performing mills.

SAFEST MILL CONTEST

8

Capital Expenditures get a Billion-Dollar Boost With the impetus of the federal government’s Green Transformation Program, most spending this year is directed to green energy, energy efficiency, and pollution abatement.

2010 PAPTAC Annual Meeting and EXFOR Review The messages weren’t new — cut costs, go green, move into biorefining — but as real-world events catch up with earlier predictions, the oftrepeated mantras had a new measure of credibility.

Blueprint for the Bioeconomy An FPAC study champions integrated pulp and paper mills plus bioenergy and bio-materials as the best path for the Canadian industry.

CAPITAL EXPENDITURES

10

TECHNICAL PAPERS

19

PAPTAC Abstracts A brief introduction to some of the technical papers available from the Pulp and Paper Technical Association of Canada at www.paptac.ca

20 Nutrient Optimization for Pulp and Paper Wastewater Treatment

Plants – An Opportunity for Major Cost Savings

By R. Kenny Over-addition of nutrients is common, but not often recognized. New nutrient assessment methods provide opportunities to optimize WWTP.

25 30 35

Low Consistency Refining of Wood Shavings

By T. Kang, G. Soong, J.A. Olson, and D.M. Martinez The maximum paper strength of LC refined wood shavings was lower, but improvements are seen in light scattering coefficient and brightness.

IN EVERY ISSUE

4 6, 7, 34

39

40

41

42

Editorial News Calendar of Events Technology News Classified Ads Photo File

50% Reduction in Thermal Energy Usage at Alberta Newsprint

By S. Singh, C. Mills, and A. World A review of projects implemented at Alberta Newsprint Co. which reduced natural gas usage by 50%.

MISSION STATEMENT:

On-line Fiber Orientation Measurement and Control

By T. Sasaki, H. Sano, J. Yamamoto, H. Todoroki, K. Ono and T. Ochi Online control of fibre orientation has reduced twist-curl by more than 50% on one paper machine.

Authorized to publish papers of the Pulp and Paper Technical Association of Canada, which are identified by the symbol

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To promote the pulp and paper industry in Canada by publishing news of the people and their innovations in research, technology, management and financing, as well as forecasts of future trends.

Serving the industry since 1903.

March/April 2010 PULP & PAPER CANADA

3

EDITORIAL

Moving in a positive direction

S

o much has happened in recent weeks. The industry is moving quickly, seeming to redirect its energies from reactive to proactive. Some new players are on the scene, but in other cases it’s the same players, shuffled around the board.

Fraser Papers is a case in point. On the one hand, its specialty papers business has been spun off and sold to its creditors. No significant changes have been announced, just a renegotiation of the union contracts. On the pulp side though, Fraser’s Thurso, Que. mill goes to new money, a Canadian company taking its first foray into manufacturing on home soil.

Big changes are planned for the Thurso operation, transforming it into a specialty pulp operation (dissolving pulp) to enter the rayon market. Significant bucks will also be thrown at establishing electrical generating capacity based on biomass.

Speaking of biomass, there’s much activity on that front as well. Metso has thrown its hat into the ring, saying it will develop a biorefinery technology for pulp mills, in cooperation with Domtar and Stora Enso. This, for North American mills, is the first biorefinery option from a known quantity, a respected, long-standing industry supplier. In other biorefinery news, Lignol is forming partnerships to move its biofuel technology forward, and Nexterra has a biomass-to-syngas system operating in a B.C. mill. UBC, at its Vancouver campus, is going to heat with biomass, using Nexterra technology. Again, some new players, some old.

Stepping back from commercial activities to R&D topics, I extend congratulations to three Canadian scientists. Dr. Richard Kerekes and Dr. Patrice Mangin have been honored

by TAPPI: Kerekes with the association’s highest honour, the Gunnar Nicholson Gold Medal, and Mangin with the distinction of being a TAPPI Fellow.

Dr. J. David McDonald received PAPTAC’s highest honour, the John S. Bates Memorial Gold Medal.

I had the pleasure of joining Kerekes and Mangin, and many of their students, for cocktails and dinner after the PAPTAC Annual Meeting. (See the photos on page 42.) Represented at the dinner were students from Spain, Iran, Nigeria, Finland, China, France, all seeking the chance to study with Canadian mentors.

Canada has a level of cooperation among its researchers that is unique in the world, says Kerekes. We now have 15 research bodies affiliated with our industry: seven pulp and paper centres, and eight networks. That gives us the combined brain power of 175 PhD students looking for ways to better understand our industry and move it forward.

Pushed by market forces, and pulled by the ideas of our research sector, the Canadian industry is moving toward the higher-value uses of wood fibre that will carry it successfully into the future.

Cindy Macdonald Editor

4

PULP & PAPER CANADA March/April 2010

EDITORIAL Editor CINDY MACDONALD 416-510-6755 cindy@pulpandpapercanada.com Contributing Editors HEATHER LYNCH

Sustaining member, Pulp and Paper Technical Association of Canada; Member, Canadian Business Press and Audit Bureau of Circulation.

ADVISORY BOARD Richard Foucault Greg Hay Dr. Richard Kerekes Barbara van Lierop Dr. David McDonald Dennis McNinch Dr. Yonghao Ni Bryant Prosser Dr. Paul Stuart Ross Williams

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INDUSTRY NEWS

Photo courtesy Truck News

Alberta log hauling configurations cut trucking costs significantly

VANCOUVER – Collaboration between FPInnovations – Feric Division, the government of Alberta, Alberta Forest Products Association, and forest companies has led to new, increased axle weight allowances and the use of new log hauling configurations for the Alberta forest industry.

“It’s safe to say that we played a key role in the process, and that our work helped the Alberta forest industry to obtain new, more productive log hauling configurations that will help to considerably reduce their trucking costs,” said Eric Amlin, head of the Transport

Research Group at FPInnovations, Feric Division.

Alberta Transportation announced new increased axle weight allowances for six different existing log hauling configurations, and allowed the use of two new 9 and 10-axle B-train type configurations. The productivity improvements for the existing fleets range from 3 to 11 tonnes depending on the configurations.

As for the new B-trains, the 9-axle and 10-axle units will have winter payloads of about 53 and 59 tonnes respectively.

The Alberta forest industry and Alberta Sustainable Resource Devel-

opment conducted a competitiveness review to provide the industry with more efficient and competitive solutions; one of the outcomes of this review was a recommendation to explore improving log truck productivity. Configurations with greater payload capacities translate into fewer trips required to haul a given amount of volume from a particular location thereby reducing costs as well as GHG emissions. In response, Alberta Infrastructure and Transportation convened an industry/government task force with FPInnovations, Feric Division participating in a technical support role.

UBC’s Kerekes receives TAPPI’s 2010 Gunnar Nicholson Gold Medal Award NORCROSS, GA. – TAPPI’s most prestigious annual award will this year go to Richard J. Kerekes, PhD, Professor Emeritus with the University of British Columbia in Vancouver.

Kerekes will receive the 2010 TAPPI Gunnar Nicholson Gold Medal Award at a ceremony on May 4, during PaperCon. “Dr. Kerekes’ contributions to research, technology, and education for our industry over a 38-year period are exemplary and make him a deserving recipient for TAPPI’s highest honour,” says Larry N. Montague, president of TAPPI. “He has made numerous significant contributions to papermaking technology during his career, including founding the Pulp and Paper Centre at the University of British Columbia where he established a research program between UBC and Paprican.”

“To a remarkable degree, he has contributed to most all of the unit operations

in papermaking, from stock chests to calenders,” said Gary A. Baum, 2009 Gunnar Nicholson Gold Medal Winner, who nominated Dr. Kerekes for the award.

“His research has been characterized by a blend of solid science and the application of fundamental principles to the solution of practical problems.”

Kerekes spent the bulk of his career with Paprican, the Pulp and Paper Research Institute of Canada, now known as FPInnovations, serving from 1971-2001. He served as the director of the Pulp and Paper Centre at the University of British Columbia from 1983 until 2005, when he retired from UBC. Dr. Kerekes has made outstanding contributions in education. As the first Paprican person to relocate to Western Canada in 1978, he was charged with building a program with the University of British Columbia. While there he

founded the $6-million Pulp and Paper Centre; orchestrated a research program between UBC and Paprican; co-led the establishment of a Pulp and Paper Master of Engineering Program; and founded an Advanced Papermaking Initiative in 1998 based on a $8.5-million endowment from the Province of British Columbia.

Kerekes graduated from the University of Toronto with a Bachelor of Applied Science and Master of Applied Science in Mechanical Engineering. He earned his PhD in Chemical Engineering from McGill University.

FPINNOVATIONS STUDIES BIODIESEL FOR OFF-ROAD MACHINERY…CANFOR REACHES AGREEMENT WITH UNITED STEELWORKERS…CATALYST PAP s s s

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PULP & PAPER CANADA March/April 2010

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INDUSTRY NEWS

Fortress Paper to convert Fraser’s Thurso mill to dissolving pulp, bioenergy VANCOUVER – Fortress Paper Ltd., a B.C.-based producer of security and specialty papers, has agreed to acquire the assets of Fraser Papers’ northern bleached hardwood kraft mill in Thurso, Que., for $3 million. Fortress Paper intends to convert the mill into a specialty cellulose (dissolving pulp) operation, and concurrently, to build a biomass-based cogeneration plant at the Thurso mill which will produce green electricity.

The Thurso mill will be acquired by a wholly-owned subsidiary, Fortress Specialty Cellulose Inc. It will be Fortress Paper’s only mill in Canada.

The company expects to spend approximately $153 million to convert the nonoperating northern bleached hardwood kraft (NBHK) mill into a high quality specialty cellulose mill and to construct a

new cogeneration facility. The specialty cellulose mill is planned to have an annual production capacity of more than 200,000 air dried tonnes and is expected to be completed in mid-2011.

Fortress Specialty will focus on producing dissolving grade cellulose for the textile industry, primarily targeting viscose fibre (rayon) products.

Fortress Paper also plans to construct a 25-megawatt cogeneration facility to service a net 18.8-megawatt power supply agreement over a 15-year term. The location of the cogeneration facility provides it with access to on-site generation of biomass and an extensive local network of chip and other biomass suppliers. It is expected to be supplying electricity in the fourth quarter of 2012.

STOPS, STARTS, CHANGES …

The company cites a combination of factors for the shutdown, including a drastic decline in North American newsprint demand, the rising value of the Canadian dollar, increased costs for raw material, and an overcapacity in the newsprint manufacturing sector.

Atlantic Packaging’s tissue business at the Whitby mill was purchased by Cascades Inc. in August 2009.

AbitibiBowater plans to indefinitely idle one of its two paper machines at its Thorold South facility in Thorold, Ont., resulting in 100 layoffs. Company spokesman Jean-Philippe Côté said the shutdown on April 12 is related mainly to the decline in its North American newsprint market. “Management and related stakeholders will work on a viable plan so the mill becomes and remains competitive going forward,” Côté said.

Atlantic Packaging Products Ltd. closed its recycled newsprint mill in Whitby, Ont. The facility recycled more than 200,000 tonnes of used newspapers and magazines annually, and employed 151 people.

PEOPLE….

NSK Canada Inc. welcomes Michael St. Jacques to the position of general manager for the global bearing and linear motion company’s Canadian operations. St. Jacques has immediate plans to expand NSK’s technical support team in the Atlantic Region, Ontario, Quebec, and Alberta.

Domtar Corporation will permanently close its coated groundwood paper mill in Columbus, Mississippi, and exit the coated groundwood paper business. The Columbus facility has an annual production capacity of 238,000 tons of coated groundwood and 70,000 metric tons of thermomechanical pulp.

Canfor Pulp Income Fund has appointed Sean Curran as vice-president, sales and marketing, Canfor Pulp Holding Inc., the general partner of Canfor Pulp Limited Partnership, effective May 1. Prior to joining CPLP, Curran held senior management positions with Norske Skog Canada Ltd., Atlantic Newsprint Company and C.P. Forest Products.

BIOREFINING

UBC selects Nexterra/GE biomass power system for campus energy project

VANCOUVER - The University of British Columbia (UBC) will install at its Vancouver campus an on-site biomass-fuelled combined heat and power (CHP) solution developed

by Nexterra Systems Corp. and GE Power & Water’s gas engine division.

The CHP system will provide clean, renewable heat and electricity for the campus, while offering a platform for bioenergy research.

Lignol signs partners for development of biofuel from wood

VANCOUVER – Lignol Energy Corporation and Novozymes have established the framework of a multiyear collaboration agreement to optimize the latest generation of Novozymes’ enzymes for use in Lignol’s cellulosic biofuel process.

Lignol plans to construct largescale biorefineries for the production of cellulosic biofuel from wood chips and forestry residues. Novozymes supplies enzymes that convert cellulosic biomass into sugars that can then be fermented into ethanol. The parties plan to use Lignol’s fully integrated industrial-scale pilot plant in Burnaby, B.C., to optimize enzyme performance across a range of cellulosic feedstocks in Lignol’s unique process.

In addition, Lignol and building materials supplier Kingspan Group PLC will cooperate on the development of commercial applications incorporating Lignol’s unique class of High-Purity Lignin and lignin derivatives (HP-L™ lignin) into various products. In converting non-food cellulosic biomass feedstocks, such as agricultural residues and forestry waste, into ethanol, the Lignol biorefining process fractionates the biomass and extracts lignin, to produce a range of unique HP-L lignin materials.

These compounds have been shown to have application in a wide range of industrial products.

PER PROPOSES RESTART PLAN FOR ELK FALLS PAPER MILL…UNIONS ACCEPT WAGE DEFERRAL AT KRUGER CORNER BROOK…FRASER PAPERS’ EDM s s s pulpandpapercanada.com

March/April 2010 PULP & PAPER CANADA

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SAFEST MILL CONTEST

Send them home safe,

every day

Good employers show that they care about the safety of their workers and won’t compromise on safety when profits are down.

By Heather Lynch

F

or Sonoco’s paper mill in Brantford, Ont., safety literally comes before everything else. “Not one pound of paper or one minute or production is worth putting an employee at risk,” says Jim Maloney, plant manager.

“In Brantford, there is a trust between employees and management and everyone works together towards the common goal of all employees returning home to their families every day safely.”

According to Tom Bailey, manager of forestry and utilities, industry and labour services for WorkSafe BC, it is this commitment and dedication that ensure safety. “Above all, the employer must demonstrate that they genuinely and honestly care about the well being of their employees, that they value the employees, and they will invest in their health and safety. In short, the employer must demonstrate the ‘value’ of health and safety in the workplace and that this value will not be compromised regardless of economic conditions.”

When asked if a tough economic climate makes safety investments difficult, Michael McIllwraith, health, safety and environmental manager for Irving Tissue 8

PULP & PAPER CANADA March/April 2010

in Toronto, responded with “absolutely.”

“But Irving Tissue will not compromise safety during times of financial challenges. Good business continuity integrates safety requirements and related costs into business planning that allows for efficiency and profitability without compromising the safety of our biggest resource – our people!”

Business continuity is another challenge for Canada’s forestry industry. In an operating environment that experiences frequent shutdowns, attention to safety-related detail becomes increasingly important. Sonoco has taken a number of steps to ensure that safety continues to progress and adapt to an operating environment that frequently stops, changes, and restarts. The Brantford facility typically undertakes a maintenance shutdown every six weeks, and conducts safety discussions with work crews before the work begins. A dedicated “safety point person” is also identified during the shutdown to perform continual tours to audit work areas.

Longer shutdowns adopt somewhat different procedures, but the emphasis on safety culture remains. Irving Tissue’s

McIllwraith explains: “During longer shutdowns due to business conditions or over holidays, we still have the safety talks and we also increase employee interactions with the supervisors to keep everyone focused. Another item which works for us is setting up safety games, which start before the downtime and continue after the mill starts back up.

This way the employees are discussing safety during their first days back and we keep safety at the forefront, resulting in better employee awareness.”

Sonoco takes a similar approach, albeit under somewhat different operating conditions. Noting the mill has some planned shutdowns, but that production is by and large continuous, the facility makes use of Current Best Approaches (CBAs), Job Safety Analysis (JSAs) and risk predictions that are reviewed daily.

When restarting a machine that has been idle, Sonoco respects machinespecific procedures and references its CBAs. Bailey suggests a number of processes that have been shown to lead to reductions in accidents and industrial diseases on the job. pulpandpapercanada.com

SAFEST MILL CONTEST Safest Mill in Canada Contest Results, 2009

1

Conduct risk assessments of all phases of the work process. Where possible, ‘engineer out’ the on-site risks.

Where that isn’t possible, plan work (risk reduction plan) and establish work procedures that reduce or eliminate the risk. Communicate these procedures through training and follow-up coaching to ensure all workers are aware of the risks and the methods available to overcome them.

Establish a quality control process and put it in place to ensure safe work procedures that have been established are used in the field. Supervisors must take corrective action if the work isn’t being conducted according to the risk reduction plan and safe work procedures.

Emphasize the positive. When the work is being done correctly, supervisors should compliment folks who are performing the work correctly and safely.

Finally, audit the process and deliverables in the field to adjust the standards of performance where necessary and evaluate the implementation of the risk reduction program.

2 3 4

While accident rates in forestry in B.C. have plunged dramatically over the past two years, Bailey notes that in times of fiscal restraint, it is critical to not become complacent when it comes to safety, regardless of favourable accident frequency rates.

“When times are economically tough, adherence to the basic principles becomes even more important,” Bailey cautions. The benefits of doing so are multiple, he notes. “In addition to accidents and industrial diseases declining, financial benefits arise because the things which cause inefficiency and dollar losses on the job, are virtually identical to the things which are underlying causes of worker accidents. Studies of ‘best in industry’ employers demonstrate that the leaders in ‘business’ are also leaders in safety and health.”

At the end of the day, promoting a safe work culture makes sound business sense too.

PPC pulpandpapercanada.com

Each year, Pulp & Paper Canada undertakes a survey to position pulp and paper facilities according to their safety rankings. Mills are evaluated according to the number of recordable incidents each month. These survey findings serve as a benchmark not only for the winners but also for every facility endeavouring to create a workplace characterized by a strong safety culture. We thank these companies for their participation in the 2009 survey and hope that 2010 is a safe and prosperous year for all Canadian mills

CATEGORY “A” OVER 100,000 MANHOURS PER MONTH Domtar Inc., Windsor, QC Kruger Inc., Trois-Rivières, QC

TOTAL RECORDABLE INCIDENTS

TOTAL HOURS WORKED

MILL FREQUENCY

9 27

1,390,282 1,370,043

1.29 3.94

CATEGORY “B” 50,000 to 100,000 MANHOURS PER MONTH Emballages Smurfit-Stone Canada Inc., La Tuque, QC Alpac, Alberta Pacific Forest Industries Inc., Boyle, AB AbitibiBowater Inc., Baie-Comeau, QC Kruger Inc., Bromptonville, QC Irving Pulp & Paper Ltd., Saint John, NB Irving Tissue, Toronto, ON Canfor, Prince George Pulp & Paper, Prince George, BC Hinton Pulp (Div. Of West Fraser Mills), Hinton, AB Irving Paper, Saint-John, NB Kruger Wayagamack Inc., Trois-Rivières, QC AbitibiBowater Inc., Iroquois Falls, ON Canfor, Northwood Pulp Mill, Prince George, BC HSPP Ltd, Howe Sound Pulp & Paper, Port Mellon, BC Zellstoff Celgar Limited, Castlegar, BC Catalyst Paper, Crofton, BC Fraser Papers, Edmunston, NB Catalyst Paper, Powell River, BC Tembec Inc., Spruce Falls Operations, Kapuskasing, ON Kruger Inc., Corner Brook Pulp and Paper Ltd., Corner Brook, NF

3 8 8 7 8 9 9 9 11 13 10 17 16 17 24 19 21 18 26

874,246 1,040,306 1,023,243 716,413 765,990 699,458.75 674,006 659,562.05 724,795.25 845,916 631,675 951,440 854,575 737,377 942,244 717,687 761,571 619,060 818,965

0.69 1.54 1.56 1.95 2.09 2.57 2.67 2.73 3.04 3.07 3.17 3.57 3.74 4.61 5.09 5.29 5.51 5.82 6.35

CATEGORY “C” LESS THAN 50,000 MANHOURS PER MONTH Sonoco Canada Corporation, Brantford, ON Canfor, Intercontinental Pulp, Prince George, BC AbitibiBowater Inc. (Bowater Mersey), Liverpool, NS Weyerhaeuser Canada, Grande Prairie, AB Alberta Newsprint Company, Whitecourt, AB Kruger Inc., Montreal, QC AbitibiBowater Inc., Clermont, QC Quesnel River Pulp, Quesnel, BC AbitibiBowater Inc., Thorold, ON JD Irving Ltd., Irving Tissue, Saint John, NB Northern Pulp Nova Scotia Corp., New Glasgow, NS JD Irving Ltd., Lake Utopia Paper Ltd., St. George, NB Slave Lake Pulp Corporation, Slave Lake, AB Daishowa Marubeni International, Peace River, AB Catalyst Paper, Port Alberni, BC Meadow Lake Mechanical Pulp Inc., Meadow Lake, SK Tolko Manitoba Kraft Papers, The Pas, MB Millar Western Forest Products, Whitecourt Pulp, Whitecourt, AB Cascades Groupe Carton Plat East Angus, East Angus, QC Catalyst Paper - Elk Falls, Campbell River, BC Norampac Inc., Trenton, ON Papiers White Birch, Papier Masson Ltée, Gatineau, QC Minas Basin Pulp & Power Co. Ltd., Hantsport, NS Catalyst Paper - Paper Recycling, Vancouver, BC

0 121,659 2 482,966 2 408,379 3 582,124 3 470,847 2 272,950 5 570,800 3 235,602 7 542,050 3 218,833 8 549,447 4 267,512.5 3 200,518 10 583,508 11 535,546 8 353,328.8 12 526,207 6 225,875 5 164,060 8 231,843 7 194,399 12 308,607 14 285,151 5 92,722

0.00 0.83 0.98 1.03 1.27 1.47 1.75 2.55 2.58 2.74 2.91 2.99 2.99 3.43 4.11 4.53 4.56 5.31 6.10 6.90 7.20 7.78 9.82 10.78

March/April 2010 PULP & PAPER CANADA

9

CAPITAL EXPENDITURES REPORT

Billion Dollar Boost Viewpoints vary on whether to spend or sit on discretionary dollars this year, but everyone has said “yes please” to government injections of black liquor credit money

B C MC

T

his February Natural Resources Canada (NRCan) announced that Mercer International was the first company to receive funding under the Pulp and Paper Green Transformation Program (PPGTP), to the tune of $40 million. Mercer will use the money to complete its Green Energy Project at its Celgar mill near Castlegar, British Columbia.

Mercer began the $55M Green Energy Project in May, 2008. It includes the installation of a 48 megawatt (MW) condensing turbine that will increase the mill’s installed generating capacity to 100 MW. Once the upgrade is completed in late 2010, the Celgar mill will able to use waste heat, turn more wood waste into more steam, and generate more bioenergy.

Mercer reports that the Green Energy Project also includes upgrading the mill’s bark boiler and steam facilities.

NRCan announced the PPGTP in June, 2009, with the goal of funding pulp and paper mill projects that have environmental

benefits. At the same time the PPGTP restores some balance in the North American industry, explains Catherine Cobden, vice president of economics and regulatory affairs, Forest Products Association of Canada. “There was a significant bioenergy subsidy in the United States. The PPGTP was a way to level the competitive playing field.”

Tom Rosser, director general, policy, economics and industry branch of Canadian Forest Service, which is a branch of NRCan, elaborates: “PPGTP is a Canadian program focused on the Canadian situation and Canadian needs. Pulp and paper is an increasingly global industry and Canada is a major exporter. As a result, the program design certainly took account of policy and market developments in the United States, Europe and elsewhere.” Too, he notes, “Pulp and paper is Canada’s largest industry energy user and it has a unique ability to power itself.”

One might also point out that the government is not indulging in hyperbole Green Transformation Program credits in pitching the PPGTP as an investment: $ million P&P companies must spending the money AbitibiBowater $33.2 AlPac Forest Products Inc. $62.9 on capital projects, which will yield endurAV Group $36.4 ing return on investment.

“The main objective of the PPGTP is Canfor Pulp LP $122.2 Cascades Inc. $6.1 to improve environmental performance at Catalyst Paper Inc. $18.0 pulp and paper facilities in Canada. Sustainability and economic performance are Daishowa-Marubeni Inc. (including Cariboo Pulp and Paper joint-venture with West Fraser Mills) $59.1 increasingly interrelated, with strong enviDomtar Inc. $143.5 ronmental performance a source of competitive advantage. A lot of projects will West Fraser Mills Ltd. (including Cariboo Pulp and Paper joint-venture with Daishowa-Marubeni) $88.4 be energy projects, but we also expect that Fraser Papers Inc. $33.1 projects will advance other environmental Howe Sound Pulp & Paper $45.5 objectives, such as air and water quality.

Irving Pulp & Paper $33.4 While energy efficiency is certainly an Kruger Inc. $6.9 important part of environmental integrity, Meadow Lake $2.6 there is no special focus on it. We are not Mercer Celgar $57.8 trying to privilege energy efficiency or air Nanaimo Forest Products $26.9 quality projects over green power or water Neucel Specialty Cellulose Ltd. $6.5 quality, for example,” Rosser explains.

Northern Pulp Nova Scotia Corp. $28.1 The first task of the PPGTP was to SFK Pulp $20.9 allocate credits to P&P companies: Any Smurfit-Stone Container Corp. $29.6 company that produced black liquor as of Tembec Inc. $24.2 January 1, 2009 was invited to apply for a Terrace Bay Pulp Inc. $19.2 $0.16/litre credit. The cutoff date to apply Tolko Industries Ltd. $13.4 Weyerhaeuser Canada Inc. $32.4 for credits was last September 18. NRCan announced the credits on October 9.

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PULP & PAPER CANADA

March/April 2010

pulpandpapercanada.com

CAPITAL EXPENDITURES REPORT Easy money

when looking at the capital project spending patterns of P&P Twenty four companies, representing 38 mills, qualified. The companies. Canfor Corporation, for example, reported capital size of the credits range from $2.6M for the Meadow Lake spending of $39.9M in 2008 and $17.9M in 2009, but made Mechanical Pulp Inc., to $143.5M for Domtar Inc. no prediction for 2010 in its December quarterly report. With The terms for turning credits into cheques are very user- $122.2M in PPGTP credits, however, Canfor surely has extenfriendly, Rosser explains. “What is really significant in terms sive visions of sugarplums. of investments that are made is that companies that generate This March 6, opinion250.com reported that Canfor Pulp credits at one facility can use the money at any of their Canadian Limited Partnership had submitted two projects to NRCan pulp and paper mills. So a much larger number of mills [than under the PPGTP, with a value of $15M: The first one will on that October, 2009 list of 38 mills] will be eligible for the reduce odour emissions at its Prince George Pulp and Paper PPGTP money. We want the recipient companies to be able to mill; the second will increase green power generation at the mill. make the most efficient use possible of the credits.”

The on-line news source notes that these two projects are part of Even companies in receivership or under creditor protec- a larger program of energy and environmental projects Canfor tion, such as Fraser Papers and AbitibiBowater, were eligible will undertake with its PPGTP credits. for credits. “Whether a company is under protection in and In a November, 2009 information brief, Canfor explains that of itself doesn’t affect their status under the program,” Rosser the odour reduction project will decrease total reduced sulfur, comments. Neither Fraser Papers and AbitibiBowater were already cut by 80% in the 1980s, by half. The expected compleforthcoming about their plans for PPGTP funds or any other tion date is June, 2011. Equipment such as ducting, condenser capital projects they might launch this year. and a reheater will be housed in a new building.

There are more easy terms: It is of no consequence that conThe biofuel power generation project is designed to generate struction of a project, such as Mercer’s Green Energy Project, an additional 11,000 mWh of electrical power. This project is might have started before the announcement of the PPGTP. expected to be completed by December, 2010.

Any costs incurred after the program announcement date last According to the B.C. government’s major project invenJune are eligible for reimbursement, even those incurred by tory, Canfor is planning to spend $90 million for upgrades to projects launched before the PPGTP approved Last year we put pretty well all of our cap-ex them; that said, projects have to pass environmental review and meet the program criteria. Comprojects on hold. This year we are doing safety, panies are not required to make matching funds. environment, anything with a very quick return They need not use Canadian technology or experon investment. They are not big projects, but tise either, although Rosser comments, “I expect, though, that most or all projects will, in some way.” they are definitely a priority.

Pilot projects are “absolutely” eligible. “Demon— Terry Gerhardt, Minas Basin Pulp and Paper strable environmental benefits is the only test. We expect to see a mix of projects come forward, ranging from those the company’s Northwood pulp plant including replacement of using more proven technologies to those based on more experi- the recovery boiler. A further $30 million worth of upgrades is mental technology,” Rosser says. planned for the feed water treatment system at Canfor’s Prince Companies can also use funds from other government George pulp plant, which includes the addition of a precipitator sources to help fund their PPGTP projects. “Projects can be to the exhaust system. funded in whole or in part from PPGTP,” Rosser says. As well, Although NRCan had made only one PPGTP funding companies do not have to produce finished, operational projects announcement by early March, two other companies spoke by the program cutoff date of March 31, 2012. They just have with Pulp & Paper Canada magazine about their PPGTP credit to spend their credits by then. spending plans. Northern Pulp Nova Scotia Corp., which has And yes, the program is capped at $1B, but the credits $28.1M in credits, would like to make recovery boiler improveannounced last October added up to only $950.4M. As of ments at its 42-year old mill in Pictou, N.S. Other than that, late February P&P companies had submitted project funding says Don Breen, vice-president of strategic planning and govrequests valued at $350M, and applications were still rolling in, ernment affairs, “We haven’t decided what we are going to do. according to Rosser.

We had a wish list of projects [before the PPGTP was created].

Rosser declined to share specifics about exactly what projects In the last three months we have looked throughout the plant to companies were applying for. In the rough though, he says, see what we can do. The studies are almost wrapped up. It is a “Energy efficiency projects will be significant. There are also good chunk of change and we want to spend it wisely.” local air and water quality projects. But the real focus will be on Northern Pulp has allocated between $2M and $2.5M energy. The industry has set a goal for itself of becoming a net capital spending for 2010 that is unrelated to the PPGTP, but source of green power within a decade. The PPGTP will play which, juxtaposed with its PPGTP credits, certainly reflects an important role in helping them to get there.” their tremendous importance to the company. “The economic conditions in Canada are still not that good,” Breen observes.

More PPGTP project spending Northern Pulp is considering replacing some of its green and The significance of the PPGTP to the industry is evident black liquor tanks and is shopping for a replacement bulldozer, pulpandpapercanada.com

March/April 2010 PULP & PAPER CANADA

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CAPITAL EXPENDITURES REPORT which will cost about $200,000. This year is also the fourth year of a five-year electrical breaker upgrade program.

Another interesting news tidbit is that the Nova Scotia government is loaning Northern Pulp $75M to purchase 475,000 acres of land. Although Breen does not count this as a capital expenditure, why split hairs in these hard times? After all, the Canada Revenue Agency regards land as a capital acquisition.

Aside from the 570-acre mill site the company owns, this will be its first ever land holding.

Domtar announced in its Q4 2009 report that its estimated capital expenditures for 2010 would be in the range of $160M to $180M, excluding PPGTP-funded projects. About $100M of that will be on maintenance and environmental projects across its 15 P&P mills. The total is well up from the $106M it spent in 2009, almost all of which was on maintenance and environmental projects. Domtar spent next to no discretionary dollars in 2009, according to Pascal Bossé, vice-president, corporate communications and investor relations.

This year will be much happier. “It would not be a stretch to say that when we started 2009 it looked like the economy was going down the drain. Will this be a capital U recovery or a W? The jury is still out. Our financials are stronger and we can look to the future with a lot of confidence,” Bossé says.

Capital projects this year will increase energy production and energy efficiency, with upgrades to the most recent technologies, according to Bossé. “We will be improving operating efficiency and throughput by reducing bottlenecks.”

At its Kamloops mill, Domtar will upgrade the recovery boiler and reduce air emissions and build two new haystacks.

“Our CEO John Williams has said that Kamloops will receive

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PULP & PAPER CANADA March/April 2010

the lion’s share of Domtar’s PPGTP funds,” Bossé says. Specifics will be made public when a contribution agreement is in place with NRCan. When asked what Catalyst Paper might do with its $18M PPGTP credit, Lyn Brown, vice-president, corporate relations and social responsibility says, “Ours is a capital-intensive business, so $18M is a relatively modest sum to work with. We are currently assessing potential projects to be sure we put forward the most optimal projects. We haven’t yet finalized any decisions.”

Beyond that, she adds, “Cash preservation remains a priority going forward,” echoing the company’s 2009 year end report, in which it warns, “ … a cautious approach with regards to capital investments in 2010 ...”

SFK Pulp reported last December that in response to winning a Hydro Quebec contract to purchase power co-generated by biomass, it would increase its green energy production capacity by 9.5MW, to 42.5MW. Noting that it has a $20.9M PPGTP credit, it reported that it, “will be submitting the turbo generator project of its Saint-Félicien mill for program approval.”

In an announcement attributed to Fredericton’s Daily Gleaner, AV Group plans to spend $45M in upgrades at AV Nackawic, including increasing its dissolving pulp production by 25%, to 600 tonnes a day. It also has plans this year for increasing energy efficiency, burning less oil, and improving the efficiency of its biomass burning operation. AV Group also wants to increase dissolving pulp production at Atholville by 30 tonnes per day.

In February, the Hinton Voice reported that West Fraser Mills Limited might spend some of its $88.4M of PPGTP credits on a $15M pressure diffuser in its Hinton, Alberta pulp mill.

Further illustrating just how difficult the economic environment is for P&P companies, Minas Basin Pulp and Power in Nova Scotia is still not prepared to go ahead with its $20M hog fuel boiler. “We worked all 2009 engineering it, getting environmental permissions. We are still working on the engineering, and when we feel we can do it, we will be ready to go,” says company vice-president Terry Gerhardt.

“Last year we put pretty well all of our cap-ex projects on hold. This year we are doing safety, environment, anything with a very quick return on investment. Anything with a two-year ROI is just not happening. We are going to spend some money on energy efficiency. They are not big projects, but they are definitely a priority.

“We should, by the end of 2010, likely go ahead with efficient lighting. We are putting our funds together. The ROI is less than one year, and that is one of the big reasons we are going forward. We are doing what we say we are doing: becoming an efficient, green mill.”

With the government’s PPGTP funding earmarked for energy and environmental projects, many other mills will be making strides in that direction over the next few years as well.

PPC Carroll McCormick is a business writer based in Montreal. pulpandpapercanada.com

EXFOR & ANNUAL MEETING REVIEW

An industry in transition – 2010 EXFOR and PAPTAC Annual Meeting The messages at the pulp and paper industry’s annual gathering in Montreal weren’t new – cut costs, go green, move into biorefining – but as real-world events catch up with earlier predictions, the oftrepeated mantras gain credibility.

I

n view of the socio-economic forces battering the industry, industry experts speaking at the Pulp and Paper Technical Association of Canada’s (PAPTAC) Annual Meeting and EXFOR trade show urged participants to transform their companies and propel the industry forward in new directions.

As one FPInnovations executive noted, “The good old days will not be back.”

The annual meeting took place February 2-3 in Montreal. Although the attendance didn’t quite reach last year’s level, there were still more than 750 participants who took part in the conference and trade show, making this a major annual event in our industry.

“We were extremely pleased with the quality level of the presentations during the 20+ technical and business sessions,” says Greg Hay, executive director of PAPTAC. Both exhibitors and participants were pleased with the networking value of the event. The welcome reception on Tuesday and Wednesday’s business luncheon provided opportunities to socialize, and business sessions on climate change, carbon credits and energy management complemented the technical sessions and trade show.

“Never before has our industry faced such a myriad of internal and external change agents. This collection of change

See, touch and learn at EXFOR.

Global Business Outlook: Cautious Optimism

By Shaun L. Turriff Industry experts at Deloitte delivered cautious optimism tempered with realism on the subject of global markets and increasing competition during the first day of the PAPTAC Annual Meeting in Montreal. Opening the session, Pierre Pettigrew, executive advisor – international for Deloitte, pointed to a “fragile hope” and a pulpandpapercanada.com

Pettigrew

net improvement in the economy across the board in 2009.

Commenting on the global geopolitical situation, Pettigrew told PAPTAC delegates that the financial crisis accelerated trends that had already been

agents will stimulate and force an entirely different industry of the future,” said Jacquelyn McNutt, keynote speaker.

She predicts new product portfolios will emerge tied to public opinion and political will on the subject of carbon and climate change.

Biorefining continues to be a hot topic in paper industry circles. Several sessions addressed the technical aspects of converting existing mill assets to use biomass in novel ways, while other speakers took a more global view of climate change issues and alternative energy strategies.

As the annual gathering wrapped up with graduate student seminars on Thursday, participants went away knowing they had benefited from the shared wisdom of their colleagues in the local industry, as well as global experts in business and climate topics.

A panel discussion during a technical session on bleaching.

emerging before the crash, such as the rise of Asia. Despite the acceleration, he claimed that China is not ready for prime time, and that global leadership would rest with the United States. Pettigrew highlighted as well the return of “big government” and the often overlooked role of governance in economic matters.

Sébastian Lavoie, assistant chief economist with Laurentian Bank Securities, confirmed in numbers what Pettigrew March/April 2010 PULP & PAPER CANADA

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EXFOR & ANNUAL MEETING REVIEW Global Business …

David McDonald receives PAPTAC’s highest honour

had suggested in generalities. A modest recovery over all, but GDP growth in Asia is projected to outstrip North America by a factor of at least 3 in 2011. Lajoie closed by noting that credit remains a problem, and that diversification into emerging markets (naming China, India, and Brazil, specifically) is key to a successful future.

Climate change and carbon credits were the topic of a presentation by Skip Willis, senior advisor for climate change with Deloitte. Willis discussed problems with, and potential benefits of, the carbon credit system and specifically with bio­ sequestration (the capture and storage of greenhouse gases by biological processes, achieved through measures such as reforestation and algae production). If handled properly, he said, biosequestration represents potential low cost compliance units in the credit system. Potential disparities between U.S. and Canadian regulations, and a weak industry lobby complicate the potential benefits, however.

New faces on PAPTAC council

The 2010 Executive Council (l to r): Terry Gerhardt, Daniel Archambault, André Bernier, Martin Fairbank, Kim Madsen, Patrice Mangin. Seated: Tom Johnstone, Julia Giasson. Gerry Murray is absent.

André Bernier has been re-elected as chairman of the Pulp and Paper Technical Association of Canada for 2010.

Two new councilors began their term on the Executive Council for 2010-2012 at the Annual Meeting: Daniel Archambault, executive vice-president and COO, Industrial Products Division, Kruger Inc., and Kim L.S. Madsen, technical sales, Stowe Woodward/Weavexx.

Retiring from the Executive Council is Gerry Pageau, Howe Sound Pulp and Paper LP. 14

The industry’s top honour, the John S. Bates Memorial Gold Medal, was presented during the PAPTAC Annual Meeting to J. David McDonald for his long-term contributions to the industry.

McDonald was the vice-president, university programs and strategic partnerships, at FPInnovations – Paprican until his retirement at the end of 2009.

At Paprican, he held senior management positions as vice-president, research and education, and manager of the mechanical pulping program. Over his 31-year career at FPInnovations, Paprican, and Abitibi-Price, he has managed or made direct contributions to research in all aspects of papermaking and mechanical pulping.

“This award is especially important to me, having known [John Bates] and knowing what a driving force he was for this industry,” said McDonald.

As vice-president of Paprican, he provided the vision for the Transfor-

David McDonald receives the John S. Bates Memorial Gold Medal award from PAPTAC chairman André Bernier.

mative Technologies Initiative (nanotechnology, biorefinery, novel pulp and paper products, and optimizing the fibre value chain), which was a major change in research direction.

PAPTAC to focus on networking, information exchange Following its restructuring in 2008, the focus in 2009 for the Pulp and Paper Technical Association of Canada ­(PAPTAC) was on maintaining core activities. Chairman André Bernier said at the group’s annual general meeting that national membership has declined to 2420 members, due to mill closures and the industry slowdown.

Some highlights of association activities in 2009 are the addition of supplier members on the executive council, monthly conference calls of the executive committee, a revised publication process with Pulp & Paper Canada, the paper machine optimization seminar, and ­webinars.

Bernier says the association’s focus going forward will be quality networking opportunities and the exchange of technical information to contribute to professional development. He expects the group’s use of web-based technologies will continue to rise.

PAPTAC members voted to downsize the minimum number of council members required to form an executive council, from 9 to 7. Also, the bylaws have been changed to permit a full audit

PULP & PAPER CANADA March/April 2010

of PAPTAC’s finances every three years, with a review of the financial results being carried out in other years.

50 years and counting

PAPTAC recognizes these indi­viduals who have been members for 50 years: Robert R. Affleck Bernard Brophy J.C. Cosgrove Victor R. Coudert, Jr. John De Belle J.E. Dempsey Frank Faludi Raymond Felx François Gilbert Thomas H. Gray Stephen S. Hessian C. Robert Johnson Joseph N. Kirk Monte Marler Richard J. Martyn Murray Munsell F.G. Powell David Randall Rudi E. Richter

pulpandpapercanada.com

EXFOR & ANNUAL MEETING REVIEW Converting to a Biorefinery: The Path Forward

By Heather Lynch Biorefining continues to be a hot topic in paper industry circles. An afternoon session hosted by the Biorefinery Special Committee at the PAPTAC Annual Meeting featured presentations from Canadian and U.S. universities.

Richard Phillips of North Carolina State University presented a work he co-authored with Shu-Fang Wu, Trevor Treasure, Hou Min Chang and Hasan Jameel entitled, “Technical and Economic Feasibility of Repurposing Uneconomic Softwood Kraft Pulp Mills to Ethanol Production.” Beginning with the basic acknowledgement that slumping demand for key paper grades has prompted numerous mill closures, Phillips emphasizes that repurposing a softwood kraft mill to produce ethanol offers a number of advantages, not least of which includes avoiding a complete write-off and demolition of uneconomical mills.

The study indicated that attractive investment returns can be achieved with green liquor pretreatment, blowline refining of pretreated chips, oxygen delignification, wash press washing after oxygen delignification, additional pulp refining to open up the softwood fibres to allow efficient subsequent enzyme treatment which are fermented and distilled to 95% ethanol concentration, and then dehydrated to 99.5% ethanol content with molecular sieves. As Phillips noted, this process reuses existing woodyard, cooking, washing, oxygen delignification and bleaching towers, as well as power and waste treatment plant systems that are already in place.

Adriaan van Heiningen of the University of Maine presented his work entitled “Kinetics and Mechanism of Autohydrolysis of Hardwoods,” which he co-authored with Martin Lawoko and Xiaowen Chen. With an emphasis on extraction of hemicelluloses from wood prior to pulping in order to make co-products such as ethanol and acetic acid, Heiningen’s work expands on previous studies conducted in batch reactors, using a continuous mixed batch reactor to obtain the intrinsic kinetics of dissolution of hemicelluloses from a mixture pulpandpapercanada.com

of hardwoods. Autohydrolysis presents an inexpensive and environmentallyfriendly alternative to depolymerising the structural polysaccharides of woody biomass into fermentable monosugars in the woody biomass conversion process.

Evaluating ethanol feedstocks.

Controversy abounds regarding the economic and environmental viability of ethanol production. While there is wide recognition that a number of renewable resources can be used to produce ethanol, emphasis on the source of the feedstock is critical to undertaking an informed environmental evaluation. As Paul Stuart and Mahasta Ranjbar, the NSERC Environmental Design Engineering Chair highlighted in their work, “Comparative Life-Cycle Assessments for Different Feedstocks-to-Ethanol Production,” life cycle assessment (LCA), or the systematic approach to evaluating the environmental performance of a process, product or activity, is a methodology available and able to reveal the environmental performance of ethanol production. In their study, the authors apply the LCA methodology in order to evaluate the environmental ‘friendliness’ of ethanol produced from different feedstocks.

Mountain Pine Beetle: Assessing the Damage

By Heather Lynch A significant portion of sessions at the PAPTAC 2010 Annual Meeting was devoted to discussing something roughly half the size of a fingernail. And yet, the overwhelming devastation caused by the tiny Mountain Pine Beetle (MPB) is indisputable and calling out for industry action.

While the beetle has plagued B.C. forests for a decade, and began its migration to Alberta in approximately 2001, the forestry sector is starting to shift focus from prevention to dealing with the millions of hectares of dead lodgepole and jack pine. A morning panel session devoted to an update on the MPB in Alberta confirmed the current affected area in the province stands at 14 million hectares. While there are a number of culpable factors that contributed to the insect’s successful migration,

jet streams helped push the beetle from B.C. over the Rockies into Alberta, and the lack of colder temperatures failed to kill off the insect in sufficient numbers to save the province’s forests from attack.

The situation in B.C. continues to be dire as well. Research projects that by 2017 roughly 70% of the western province’s mature pine will have been killed off. Here too, climate change is the main contributor to the problem. The tendency towards more moderate winters has allowed the MPB to prosper, while improved fire suppression techniques have altered the age classification of forests, leaving increased numbers of older trees still standing, and highly vulnerable to beetle infestation and attack.

With lodgepole pine accounting for 30% of B.C.’s timber harvest land base, questions are now turning to how best to preserve the value of the industry’s existing capital stock. Researchers are calling for a concerted R&D effort to sustain the forestry sector’s supply of beetle-killed pine, with an emphasis on changes in pulp strength and extractives profiles over time. The main challenge, it was noted, will be how to offset future reductions in fibre quality.

Practical Advice at Energy Management Session

By Heather Lynch The Business Program held on the second day of the PAPTAC Annual Meeting explored the thorny issue of energy management from a number of different perspectives. Hosted by Hydro Quebec, the session offered presentations by the provincial energy provider, FPInnovations, Cascades, Natural Resources Canada and a number of others, with unique insights into how mills can reduce energy consumption to drive cost savings.

Jacques Perrault of Cascades provided an overview of Hydro Quebec’s “A Practical Guide to Energy Conservation in Papermaking.” Perrault informed conference attendees that a typical papermachine can in fact reduce its energy consumption by up to 20% without making any major capital expenditures.

Considering that thermal energy consumes approximately 80% of total energy demand on a papermachine, such a reduction is not insignificant.

March/April 2010 PULP & PAPER CANADA

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EXFOR & ANNUAL MEETING REVIEW

B

McNutt issues a wake-up call

aby steps will not be enough to bring this industry back to a position of strength, says Jacquelyn McNutt.

As keynote speaker at the PAPTAC Annual Meeting and EXFOR trade show, McNutt told participants, “We are in a place where incremental change is not enough. We really have to move out of our established patterns.”

McNutt is executive director of the Center for Paper Business and Industry Studies at Georgia Tech university.

She noted that many factors are affecting the forest products industry right now, including global public opinion, the push for alternative energy, nanotechnology, and digital media.

“The global political community’s response to the climate change issue will dramatically alter the industry’s competitive landscape. A lot of our behaviours end up being changed by political dogma, media, and public view, not by the truth. But true or not, we’re still going to have to respond to it.”

She also notes that companies can

expect “transient” competitive excellence in the future, with entirely new industrial complexes tied together by unique partnerships.

Nanotechnology, she feels, is going to change the way we do business in 20 years. At the same time, alternative energy will become central to our society.

New product portfolios will emerge tied to society’s carbon response. “We will witness unprecedented pressures on fibre resources for new products and from new users. Water resource limitations will, in the long run, overshadow carbon.

“If I were to advise a CEO, I’d say look at water conservation and water usage. It won’t have a short term ROI, but….

“We are going to see a special place for those with sustainable, high quality fibre, land and water resources,” McNutt predicts.

But while resources may be in short supply, the ability to change the industry is not. “Do we have a mindset to trans-

Survival in a Carbon-Constrained World

based on a low carbon intensity product.

But he closed with a caveat: will this sector lead, or react?

Don Roberts, from CIBC, while insisting on carbon’s importance to the future of the industry, cautioned against seeing it as the only issue. Roberts, supporting many of the voices heard around the conference generally, supported a model of wood plants with integrated biorefinery as one of the best possibilities for the future of the industry. Integrated models showed better ROCE, a higher employment base (important to many policy makers, he reminded the audience) and better access to low-cost fibre. Again, however, there was a caveat: presently, the industry is responding, not leading, a situation Roberts felt untenable.

Following up where Roberts left off, and covering some of the same ground as her excellent keynote address, Jacquelyn McNutt reiterated that carbon is not the be all and end all of the future for the forestry sector. McNutt is executive director of the Center for Paper Business and Industry Studies at Georgia Tech university.

By Shaun L. Turriff Wednesday afternoon’s business session at the PAPTAC Annual Meeting, sponsored by Natural Resources Canada, addressed the question “How will the Pulp and Paper Industry Evolve in a Carbon-Constrained World?” Not easily, it would seem.

Opening the panel, Jim Ferrel, Assistant Deputy Minister for Natural Resources Canada, discussed public policy considerations. Ferrel started out on a theme of change, and the resulting urgency, uncertainty, complexity, but also, importantly, the opportunity. Ferrel predicted that we will see a carbonconstrained world, higher energy prices, some form of emissions tax or cap-andtrade system and a high emphasis on efficiency. Ferrel, setting the tone for the rest of the panel, insisted that it is not enough to cut cost and to hang on, that in this instance, the past might not be a good guide to the future. He closed by stating that the sector is well positioned to prosper in a carbon-constrained world, 16

PULP & PAPER CANADA March/April 2010

“Never before has our industry faced such a myriad of internal and external change agents,” says Jacquelyn McNutt, show here with PAPTAC chairman André Bernier.

form and innovate quickly?” McNutt asks her audience. “Hell no. But that’s something that we can get.”

Public outcry based on climate change, and the public policy that follows, makes it an important issue, she noted. McNutt called for sustainable business models, while warning that the industry, as it stands, is ill-equipped to deploy new technology and cannot sustain major failure, creating a complex risk/reward pathway going forward. McNutt insisted also that the future of the forest sector lay in bioproducts, citing the relatively well tested technology, clearer markets, and available partners. McNutt tempered any enthusiasm with the statement that this also means more competition, and an eventual commodity market for many of the bioproducts, such as ethanol, to be produced.

McNutt presented production flexibility as a key to the long term success, as well as strong partnerships with capable companies, and a strong, long-term vision to guide the steps along the way.

So it might not be an easy path, but there does seem to be a way for the pulp and paper industry to move forward in a carbon-constrained world. That path, however, is open only to the leaders, not those who simply react. pulpandpapercanada.com

EXFOR & ANNUAL MEETING REVIEW

2010 PAPTAC Awards Awards for research, technical papers and service to the Canadian pulp and paper industry were conferred during the PAPTAC Annual Meeting, held February 2-3 in Montreal.

J. David McDonald was presented with the John S. Bates Memorial Gold Medal for long-term contributions to the industry.

The I.H. Weldon Award for the best paper went to Mathieu Hamelin, AFT, and Sean Delfel, James Olson and Carl Ollivier-Gooch, UBC, for their paper, “High Performance Multi-Element Foil (MEF) Pulp Screen Rotor - Pilot and Mill Trials.” For this work, Hamelin, Delfel, Olson and Ollivier-Gooch were also awarded the Douglas Atack Award for the best paper presented at the mechanical pulping sessions at the previous Annual Meeting.

The F.G. Robinson Committee Service Award was conferred upon Leszek Kosiak, Tembec Industries Inc., who served as chairman of the Energy Cost Savings Committee from 2006 to 2009.

The Douglas Jones Environmental Award for the best paper in the field of environment improvement went to Ray Kenny, Ray Kenny Environmental Consulting Inc., for his paper entitled, “Nutrient Optimization for Pulp & Paper Wastewater Treatment Plants – An Opportunity for Major Cost ­Savings.”

Yonghao Ni and Zhibin He, University of New Brunswick, were awarded the Howard Rapson Memorial Award for the best chemical pulp bleaching paper. The winning paper is entitled, “Improving Chlorine Dioxide Bleaching of a Softwood Kraft Pulp by Using Magnesium Hydroxide for pH Control.”

The Jasper Mardon Memorial Prize for the best paper contributing to the advancement of papermaking was presented to J. David McDonald and Marina Tchepel, formerly of FPInnovations – Paprican, for their paper entitled, “The Effect of Dryer Section Operation on the Linting Propensity of Newsprint.”

pulpandpapercanada.com

Shahram NavaeeArdeh, École Polytechnique de Montréal, received the C. Howard Smith Award for the best paper submission by a member under age 33. His paper is entitled, “A Novel CostEffective Technology for Pulp and Paper Mixed Sludge Drying: Experimental Results, Modeling and Techno-Economic Assessment.”

The Gadget Competition is judged by the members of PAPTAC’s Engineering and Maintenance Committee. Prizes and certificates are awarded by the sponsor, Pulp & Paper Canada. This year’s first prize winner is Michel A. Lavoie, Fraser Papers Inc., who developed a seal for a corrosive gases ventilator. The second prize winner goes to a hydraulic filter change out device developed by Greg Koopman, Zellstoff Celgar LP. The Energy Conservation Opportunity Awards are presented for the best examples of energy conservation opportunities applied in Canada. First prize went to Rick Merling of St. Marys Paper Corp. for a compressed air dryer replacement. Second prize was presented to Jan Luppens of Alberta Newsprint Company, for a 50% energy reduction in disc filter dilution pump. Sylvie Gagné of New Forest Paper Mills LP, received third prize for re-use of effluent water in the plant.

The Energy Conservation Opportunity Awards are sponsored by Pulp & Paper Canada.

Certificates of Appreciation were awarded to: Raymond Banham, Grizzleton International Ltd., for his leadership and longterm commitment to the EXFOR Committee; Pierre Gauthier, Kruger Trois-Rivières, for his leadership and exceptional service as chairman of the Process Control Committee; Dan Davies, Evonik Degussa Canada Inc., for his service and outstanding leadership as chairman of the Bleaching Committee; and Emil Koller for his outstanding contribution and long-term commitment to the Standard Methods Committee.

March/April 2010 PULP & PAPER CANADA

17

BIOMASS

Blueprint for the Bio-Economy The traditional forest products industry has a key role to play in making the bio-economy – bio-energy, bio-fuels and bio-chemicals – strong and sustainable.

By Cindy Macdonald, editor

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PULP & PAPER CANADA March/April 2010

Pyrolysis Stand-Alone

Lumber Large & Pyrolysis

CHP via Gasification

LVL Large

Lumber Large

Lumber Large & Pellets Small

Full Fractionation

Syngas for Dryers

LVL Small

Lumber Medium

OSB Large

OSB Medium

SPF West Large & Pellets Large

Torrefied Pellets

Pellets Small

Pellets Medium

Biocarbon Small

Lumber Large & Pellets Large

Pyrolysis Stand-Alone

Lumber Large & Pyrolysis

LVL Large

CHP via Gasification

Lumber Large & Pellets Small

Full Fractionation

Lumber Large

Lumber Medium

LVL Small

NBSK & H&P Large

OSB Large

Syngas for Dryer

NBSK & H&P Medium

Pellets Large

OSB Medium

Cost of Capital = 11%

Graphs courtesy of FPAC

Lumber Large & Pyrolysis

LVL Large

Pyrolysis Stand-Alone

Full Fractionation

Lumber Large

Lumber Large & Pellets Small

Lumber Medium

LVL Small

Torrefied Pellets

Pellets Medium

NBSK & H&P Large

Lumber Large & Pellets Large

Syngas for Dryer

OSB Large

Lignol Commerical Brownfield

Cost of Capital = 11%

NBSK & H&P Medium

A summary of the Future Bio-pathways report is available at www.fpac.ca.

Cost of Capital = 11%

Lumber Small

he Forest Products Association of Canada (FPAC) has released a comprehensive, firstof-its-kind study that examines a wide range of options for renewal of the Canadian forest products industry.

“The study, The Future Bio-pathways Project, focuses on the triple bottom line: clean energy, high employment, and economic recovery. The results are clear – integrating the production of bio-products and bio-energy into the existing industry is a winner on all fronts,” says Avrim Lazar, president and CEO of FPAC. The Future Bio-pathways Project involved more than 65 Canadian experts in fields as diverse as biotechnology, investment banking, and carbon pricing.

“The study shows that the best path forward is to integrate; to take pulp and paper enterprises and to add bio-energy and bio-chemicals,” says FPAC’s vice-president, economics and regulatory affairs, Catherine Cobden.

She suggests that full fractionation, or full biorefining, has emerged as the best opportunity for Canadian pulp and paper producers. “It really diversifies the product mix, into bio-energy and bio-chemicals.”

The charts at right are taken from the Future Bio-pathways report. They show return on capital employed (ROCE) for various traditional and emerging forest products. (Note: Twenty-seven technologies were studied. The charts show only those technologies for which the ROCE is above the cost of capital.)

The study results also illustrate how government policies can favor certain technologies, Cobden notes. The high ROCE for pellet businesses in Ontario, for example, is related to provincial government policy.

PPC

pulpandpapercanada.com

PAPTAC ABSTRACTS

Modelling the Effect of Plate Age on the Operation of TMP Refiners

By M. Ilich Lama, M. Perrier, and P. R. Stuart

Modéliser l’effet de l’âge des plaques sur les opérations des raffineurs de PTM

Abstract: The inherently interactive nature of the TMP refining processes is one of the most important sources of variability in TMP quality, and the operation of TMP refiners is directly affected by the condition of the refiner plates. Although in the past two decades much work has been done on the modeling of TMP refiners, current models do not account explicitly for the effect of plate age on refiner operation and pulp quality. In this work, a methodology is presented for the prediction of motor load changes over the longer-term due to plate age, using realtime data from plant operations and steady state identification techniques. The resulting model is coupled with a pulp quality predictor to study different refining conditions. The model predicts long-term drifts in pulp quality in addition to providing insight on the effect of total specific energy, refining intensity, power split, and plate age on the refining operation. Finally, the model is used to determine optimal policies for TMP refiner operation as plates wear.

Paper presented at the PAPTAC 92nd Annual Meeting in Montreal, Que., February 6-10, 2006.

Keywords: THERMOMECHANICAL PULP, REFIN ERS, PLATE AGE, STEADY STATE IDENTIFICATION, PULP QUALITY, MODELING, OPTIMIZATION Full manuscript available at www.paptac.ca.

Pretreatment of Over-Dry Grey-Stage Lodgepole Pine Chips

By I.Omholt, Z. Yuan, and B. Dalpke

Prétraitement des copeaux surséchés de pin de Murray à l’étape de gris

Abstract: Grey-stage lodgepole pine chips were dried under ambient conditions to 91% solids. Subsequent rewetting brought pilot TMP handsheet strength back close to the original level, but a small residual loss of strength should be expected. Enzymes did not seem to help. Sulphite or alkaline peroxide chip pretreatment significantly improved the strength properties at a given CSF, at the expense of higher specific energy, lower light scattering, and a few percentage points lower yield in the case of the alkaline peroxide. Practical implications are discussed.

Paper presented at the 2009 PacWest Conference, in Sun Peaks, BC, April 10-13, 2009.

Keywords: GREY-STAGE, LODGEPOLE PINE, PILOT, TMP, DRY CHIPS, REWETTING, PRETREATMENT, STRENGTH, YIELD Full manuscript available at www.paptac.ca. pulpandpapercanada.com

(Full peer-reviewed manuscripts available at www.paptac.ca)

Use of Dry Wood Chips for Thermomechanical Pulping

By I. Omholt, K. Miles, M. Stacey, D. Dranfield

Utilisation des copeaux de bois séchés pour la mise en pâte thermomécanique

Abstract: The consequences of using dry chips for producing TMP from black spruce and balsam fir have been explored in pilot scale. The results confirm that chip solids content up to about 77% in itself should not be detrimental to the properties of TMP. At around 90% solids, however, the pulp quality suffered. It was possible to rewet the over-dry chips and to recover the pulp properties to a large degree. The residual negative effect was around 2 Nm/g tensile index at CSF = 100 mL. Paper presented at the International Mechanical Pulping Conference in Sundsvall, Sweden, June 1-4, 2009.

Keywords: DRY CHIPS, TMP, BLACK SPRUCE, BALSAM FIR, PILOT TRIALS, REWETTING, HANDSHEET STRENGTH Full manuscript available at www.paptac.ca.

A Benefit Analysis of Model Predictive Machine Directional Control of Paper Machines

By J. Backström and P. Baker

Une analyse des avantages du contrôle directionnel des machines à papiers par modèle de prévision

Abstract: Increasing costs for energy and raw materials combined with a downward pressure on paper prices from global over capacity results in an ever increasing pressure on paper manufacturers to further improve operational efficiencies. While classic multivariable machine direction (MD) control has served the industry well in this regard since the late 60s, its capabilities are stretched to the limits by today’s advanced processes and stringent quality requirements. This paper provides a detailed comparison between classic multivariable MD control and model predictive MD control with a focus on improvement of paper machine operational efficiency. The paper draws on experiences commissioning model predictive control (MPC) based MD controls in the Americas.

Paper presented at the 2008 Control Systems Pan-Pacific Conference in British Columbia, June 16-18, 2008.

Keywords: OPERATIONAL EFFICIENCY, MULTIVARI ABLE CONTROL, MACHINE DIRECTION CONTROL, MODEL PREDICTIVE CONTROL, ECONOMIC OPTI MIZATION. Full manuscript available at www.paptac.ca.

March/April 2010

PULP & PAPER CANADA

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WASTEWATER

Nutrient Optimization for Pulp and Paper Wastewater Treatment Plants – An Opportunity for Major Cost Savings

WINNER OF THE DOUGLAS JONES ENVIRONMENT AWARD

By R. Kenny

Abstract: Pulp and paper wastewater treatment plants (WWTP) often add nitrogen and phosphorus to ensure optimum performance. If there are insufficient nutrients for bacterial metabolism, an increase in effluent total suspended solids (TSS), biological oxygen demand (BOD) and/or chemical oxygen demand (COD) may occur. As well, nutrient deficiency can cause or contribute to acute or chronic regulatory toxicity. Nitrogen and phosphorus are a major cost for many wastewater treatment plants and represents a major opportunity for cost reduction.

Nutrient over-addition commonly occurs but is not often recognized. Nitrogen over-addition and subsequent nitrification and denitrification can significantly increase costs. It can also contribute to or cause process upsets manifested by severe biological reactor foaming, secondary clarifier scum and/or higher final effluent BOD and TSS discharges. Phosphorus over-addition will not cause a process upset but increases operating costs and contributes to eutrophication.

Heterotrophic bacteria require nitrogen to metabolize BOD although over-addition can result in the growth of unwanted nitrifying bacteria. The nitrifying bacteria consume considerable amounts of oxygen.

For 1 mg of ammonia oxidized there is 4.6 mg/L of oxygen consumed. Nitrifying bacteria consume excess ammonia nitrogen (NH3-N) producing nitrite (NO2) and nitrate (NO3). In theory, reactor nitrate residuals should be stable if the reactor is not anoxic. When nitrate residuals are elevated secondary clarifier denitrification may occur. With this type of denitrification secondary clarifier sludge blanket can rise to the surface.

Extensive field experience utilizing newer wastewater assessment tools indicates denitrification can occur within the biological reactors of most pulp and paper WWTPs. With biological reactor nitrification and denitrification, ammonia nitrogen residuals can be relatively low and nitrate not detectable. Subsequently this frequently results in nitrogen over-addition.

The over-addition and subsequent reactor nitrification and denitrification may not cause obvious process difficulties but can occasionally cause severe upsets.

It is estimated the previously unrecognized reactor denitrification is conservatively costing the pulp and paper industry millions of dollars per year as a result of wasted nitrogen, power, defoamer and polymer costs.

The paper reviews mechanisms and conditions responsible for pulp and paper nitrification, denitrification and nutrient deficiency as well as related evaluation methods.

W

aste water treatment plant (WWTP) bacteria require nutrients to maximize BOD metabolism. The major nutrients required for bacterial growth are C, H, O, N, P and S. There are also micro nutrients needed that include Mg, K, Fe, Na, Ca, Mn, Zn, Cu, Mo as well as other nutrients (Gostick, 1990). Typically pulp and paper WWTPs are nutrient limited and only nitrogen and phosphorus chemicals are added. An upset can develop if there is a deficiency of nitrogen and/or phosphorus. Nutrient deficiency has the potential to increase TSS, BOD and/or COD losses. As well, nutrient deficiency can also cause regulatory acute and/or chronic toxicity.

All pulp and paper WWTPs require nitrogen and phosphorus for optimal treatment. Theoretically, for each 100 mg/L of BOD the bacteria require 5 mg/L of nitrogen and 1 mg/L of phosphorus. This is referred to as a BOD:N:P ratio of 100:5:1. In aerated lagoons the ratio is often referenced lower at about 100:2.5:0.5 due to bio20

PULP & PAPER CANADA March/April 2010

feedback of nutrients from benthic sludge (Foster et al., 2003).

Nutrient requirements vary significantly between WWTPs due to operating condition dynamics, type of treatment and plant design.

For these reasons it can be challenging — with significant potential for upsets — when nutrients are added based upon a BOD:N:P ratio.

The required nutrients are provided through nutrient addition, mill process and/or possibly from nitrogen fixation (Slade et al., 2004).

Faster rates of bacterial decay will lower nutrient requirements. Major factors influencing bacterial decay are sludge age and temperature, with higher values lowering nutrient requirements ­(Jenkins et al., 2004).

Generally high rate (low sludge age) activated sludge plants require more nutrients than low rate (high sludge age) plants. Aerated lagoons have lower nutrient needs due to anaerobic decomposition of benthic sludge. If the released nutrients are available to aerobic bacteria, where BOD

R. KENNY Ray Kenny Environmental Consulting Inc., North Bay, ON. pulpandpapercanada.com

PEER REVIEWED metabolism occurs, nutrient requirements will be low.

The nutrient addition rate is often based upon nutrient residuals after the first cell of treatment. Ammonia nitrogen (NH3-N) and ortho-phosphate residuals of 0.5 to 1 mg/L are typically recommended but many plants operate successfully in the 0.3 to 0.5 mg/L range (Foster et al.

2003). Target levels should be site specific as significant over-addition or deficiency can occur.

Nutrient Optimization

Ammonia nitrogen and ortho-phosphate target residuals of 0.5 to 1 mg/L prevent nutrient deficiency from occurring in most plants. Nutrient deficiency can develop when there is insufficient nitrogen and or phosphorus available for BOD metabolism. A deficiency can cause higher TSS, BOD and acute or chronic regulatory toxicity. Operating at higher target residuals minimizes the risk of nutrient deficiency but also increases operating costs, receiving water eutrophication and potentially can cause ammonia-related process upsets.

Nitrogen and phosphorus is required for the growth of BOD-consuming heterotrophic bacteria. These bacteria need nitrogen as ammonia nitrogen (NH3 N) or nitrate (NO3) as well as phosphorus to maximize BOD removal efficiency.

If nitrogen addition is greater than heterotrophic bacteria requirements nitrification can occur. Nitrification is the biological oxidation of ammonia to nitrite and nitrate. There are two classes of nitrifying bacteria that include ammonia and nitrite oxidizers. The ammonia oxidizers convert ammonia to nitrite (NO2) and nitrite oxidizers convert nitrite to nitrate. The nitrifying bacteria grow relatively slowly compared to heterotrophic bacteria (Wagner et al., 2002). Under optimum conditions heterotrophic bacteria reproduce within 30 minutes while nitrifying bacteria multiple every 8 to 20 hours depending upon the type of bacteria. Due to the faster heterotrophic growth rate they “out compete” nitrifiers for ammonia nitrogen. When nitrogen is added in excess to the heterotrophic bacteria requirements nitrification typically occurs.

Nitrification can occur over a wide range of pH, temperature and sludge age conditions; these are therefore not limiting factors for most plants. As a result pulpandpapercanada.com

nitrification occurs readily in most aerated lagoons and activated sludge plants. Even high rate activated sludge plants such as oxygen activated sludge systems will nitrify although sludge age may be relatively low. Even though nitrification frequently occurs, it often cannot be identified without specialized assessment methods.

Most of the previous work on nitrification was performed with Nitrosommonas europaea and Nitrobacter winogradskyi nitrifying bacteria, as they represent ammonia and nitrite oxidizing bacteria which are easy to obtain from international bacteria collections but may not represent those nitrifying bacteria dominant in pulp and paper WWTPs. There are sixteen ammonia oxidizers and four nitrite oxidizing nitrifying bacteria that have been identified (Juretschko et al. 1998).

Denitrification is the breakdown of nitrate to nitrogen gas by denitrifying bacteria. Textbook denitrification occurs within secondary clarifiers or quiescent zones. The released nitrogen gas causes sludge to rise from the bottom to the surface when anoxic conditions exist (Jenkins et al., 2003).

Based upon field experience utilizing nitrifying bacteria fluorescence in situ hybridization (FISH) commercial probes and other nitrification and denitrification respirometry identification methods, biological reactor denitrification frequently occurs. Prior to the development of these methods it had been assumed reactor denitrification was not possible due to positive reactor D.O. residuals. Based upon field experience using FISH probes, reactor nitrification and denitrification commonly occurs in many pulp and paper WWTPs (Kenny, 2003).

Although not previously recognized in pulp and paper WWTPs there are aerobic and facultative denitrifying bacteria that can exist in aerobic biological reactors.

Aerobic denitrifying bacteria such as Paracoccus denitrificans have been identified by FISH probes. These denitrifying bacteria can use nitrate or oxygen as electron acceptors without a time delay for mobilization of the nitrate enzymes (Austin et al.).

The large number of nitrifying as well as denitrifying bacteria increases the complexity of our understanding of nitrification and denitrification within pulp and paper WWTPs. With reactor denitrification, a per-

centage of the released nitrogen remains within the floc. When these bacteria enter the secondary clarifier or quiescent zone a fraction can float immediately upon entry.

This sludge eventually settles as the nitrogen gas dissipates over time.

For some WWTPs nitrate residuals can be an important indicator of nitrification and a valuable control tool. When nitrification is identified by significant nitrate residuals denitrification can be readily identified and controlled. If residuals are measured, nitrogen addition can be based upon ammonia and nitrate residuals.

With reactor denitrification nitrate residuals are often not detectable. As a result nitrification (and potential for denitrification) may not be recognized.

With reactor nitrification/denitrification, nitrification likely occurs at the floc perimeter and denitrification within the floc. The liquid bulk D.O. residuals can be greater than 1 mg/L but within the floc residuals may be zero if oxygen transfer rates are too low.

Reactor nitrification and denitrification is not always obvious as it may not significantly hinder WWTP operations.

Occasionally upsets develop with the cause difficult to determine as nitrate residuals are not detected. Operating personnel may incorrectly assume nitrification is not possible due to zero nitrate residuals.

In severe cases of reactor denitrification symptoms can include secondary clarifier floating sludge, sludge floating immediately upon sample collection and moderate to severe foaming. The foam is unique as it is dark and unusually viscous. The viscous foam is caused by nitrogen gas carrying bacteria to the surface where it becomes incorporated into the foam.

In less severe cases of reactor denitrification a thin layer of sludge may be observed at the clarifier surface with little or no foaming observed.

As well, nitrogen gas bubbles attached to the floc can be responsible for higher settle volume indexes (SVI). When filament bulking or nutrient deficiency cannot account for elevated SVIs it may relate to reactor denitrification.

Biological reactor nitrification/denitrification is difficult to troubleshoot and control due to the low ammonia nitrogen and nitrate residuals.

Nitrogen over-addition is not often apparent as reactor denitrification masks March/April 2010 PULP & PAPER CANADA

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WASTEWATER the over-addition. Under these circumstances plant personnel may incorrectly determine nutrient deficiency is occurring.

Anecdotal aerated lagoon field experience indicates nitrogen feed rate doubling or tripling does not cause a significant increase in ammonia nitrogen or nitrate residuals. The additional ammonia is shunted into the reactor nitrification and denitrification cycle and therefore its effects are not apparent.

Adding nitrogen in excess of heterotrophic bacteria requirements has the potential to trigger an operational upset with the severity related to the food to microbiological mass (f/m) ratio. At higher f/m the bacterial growth rates are greater resulting in decreased oxygen penetration to the centre of the floc. Under these conditions denitrification may occur within the floc.

This mechanism is similar to that responsible for the growth of type 1701 and Sphaerotilus natans filaments. Growth of these filaments is favoured when the food to microbiological mass (f/m) ratio is high and dissolved oxygen level is low (Jenkins et al., 2003). The dissolved oxygen at the floc centre may approach zero even though the bulk D.O. can be relatively elevated. These filaments grow extending from the floc surface where the oxygen concentrations are higher. Similar conditions responsible for type 1701 and Sphaerotilus natans filament growth can also explain reactor denitrification.

WWTPs may operate for extended periods without experiencing an upset due to reactor denitrification. The exact trigger conditions responsible for such an upset is not fully understood but likely relate to higher mill BOD loading and/or sludge accumulation within the biological reactor. These sludge deposits are significant reservoirs for ammonia nitrogen and organic acids that can transfer upwards into the aerobic layer by means of diffusion (Slade et al., 2004). As the quantity of sludge increases, more ammonia is released causing further nitrification. Based upon field work, ammonia nitrogen within the sludge deposits can range between 20 and 500 mg/L. This nitrogen can be available to heterotrophic bacteria for BOD metabolism or to nitrifying bacteria for nitrification.

Organic acids migrating from sludge deposits have the potential to increase the f/m ratio, maximize heterotrophic bacte22 

rial growth (e.g. zoogloeal bacteria) and decrease the D.O. within the biological floc. The rate of organic acid as well as ammonia nitrogen release is likely variable depending upon whether sludge upwelling is occurring. Subsequently this would affect nitrification as well as reactor denitrification.

When confirmed, reactor denitrification can be controlled by decreasing nitrogen feed rates and, if applicable, by eliminating problem sludge deposits.

Where reactor nitrification and denitrification is suspect, technical confirmation is required. This can be accomplished utilizing FISH probes or respirometer evaluation methods. Prior to the development of these procedures reactor denitrification was very difficult to diagnosis or control.

Nutrient optimization without appropriate methods creates difficulty as it becomes challenging distinguishing between nitrification/denitrification and nutrient deficiency.

A number of aerated lagoon and activated sludge plants have successfully reduced or eliminated nitrogen and phosphorus addition. Although nutrients are not added they are obtained from mill sources and/or nutrients originating from sludge deposits.

WWTPs considering nutrient optimization should conduct an operations assessment with a focus on nutrient management. A nutrient reduction program can include anthrone polysaccharide, ammonia nitrogen/nitrate/ortho phosphate, microbiological and nitrificationnutrient deficiency laboratory and in-situ respirometry testing. As well, some plants may consider FISH probe testing nitrifying and denitrifying bacteria.

There are filamentous bacteria such as Thiothrix spp., Type 021N that can grow at low nitrogen conditions and Sphaerotilus natans, Haliscomenobacter hydrossis and Nostocida Limicola 111 that may grow in low phosphorus conditions (Jenkins et al.).

These filaments have other growth causes unrelated to nutrient deficiency and are therefore not reliable indicators of nutrient deficiency.

Anthrone polysaccharide testing is important to establish whether nutrient deficiency exists. The anthrone polysaccharide test is a chemical procedure to measure the bacterial polysaccharide content. High amounts of carbohydrates occur

PULP & PAPER CANADA  March/April 2010

when the plant is nutrient limited. An anthrone polysaccharide content of less than 25% is normal and an indication that nutrients are not deficient (Jenkins et al., 2004). A normal polysaccharide level indicates nutrient addition is balanced or over-addition may be occurring.

Sample preparation for aerated lagoons can present challenges due to low lagoon bacterial concentrations. Lagoons often operate between 100 and 200 mg/L of TSS. The anthrone polysaccharide test requires a TSS concentration of 2,000 mg/L or higher. Aerated lagoons can determine polysaccharide concentrations by centrifuging samples. Centrifuging is required as a significant fraction of the biological TSS may not readily be captured by gravity settling (Kenny et al. 2000).

Anthrone polysaccharide testing can determine whether there is a deficiency of nitrogen or phosphorus but cannot be used to assess the degree of nitrogen over-addition. Determination of nitrification can be accomplished through microbiological techniques or with specialized respirometry procedures. If nitrification is confirmed and there are no measurable reactor nitrate residuals, it can be assumed biological reactor nitrification and denitrification is occurring.

If nitrifying bacteria are identified it is assumed nitrification is occurring.

Nitrifying bacteria can be determined by morphological phase contrast microscopic identification or by FISH probe testing.

Microscopic identification has its limitations as only two of twenty nitrifying bacteria can be identified based upon morphology. Nitrosommonas and Nitrobacter nitrifying bacteria are the only nitrifiers identifiable based upon morphology. If they are not observed, it cannot be assumed nitrification is not occurring as other nitrifiers may be present. Other nitrifying bacteria can be identified by plate culture or FISH commercial probe methods.

FISH commercial probe testing can be an important identification tool, although there may be procedural limitations. As well, under-reporting poses a potential concern due to bacterial slime that may limit probe penetration into the nitrifying bacteria.

Nitrification can also be determined with respirometry and ammonia recovery methods. In these procedures, a Strathtox pulpandpapercanada.com

PEER REVIEWED respirometer measures the specific oxygen uptake rate (SOUR) of multiple samples controlled to the reactor temperature. The SOURs can be determined as follows: • Not inhibited control – 20 ml of endogenous wastewater + 1 ml of water.

• Nitrifying inhibited control — A sample is prepared with a nitrifying inhibitor. 20 ml of the inhibited sample + 1 ml of water • Nitrification/Denitrification – 20 ml of endogenous wastewater + 1 ml of a known ammonium chloride solution.

• Nitrification Inhibitor – A sample is prepared with a nitrifying inhibitor. 20 ml of the inhibited sample + 1 ml of the known ammonium chloride solution are added to the tube.

The above tests are conducted for a specific time period or until the dissolved oxygen is depleted. The D.O. values are output to a computer with results graphically displayed. At test completion, the samples are filtered and ammonia nitrogen residuals determined for ammonia spiked and control samples. If the nitrification/ denitrification + NH3-N sample has a significantly higher SOUR than the control, nitrification or nutrient deficiency could be occurring. If the wastewater is endogenous with low soluble BODs (e.g. < 10 mg/L) and the SOURs are significantly higher than the control sample, it can be concluded nitrification is occurring. As well, if the ammonia recovery test indicates significant ammonia consumption, this can provide additional verification of nitrification.

The purpose of the nitrification inhibitor is to provide an alternative verification method. If nitrifiers are present the inhibitor should partially or completely inhibit the nitrifiers. When ammonia nitrogen is added to the inhibited sample oxygen uptake rates should be similar to the non inhibited control SOURs. As well, complete recovery of the ammonia nitrogen should be possible.

The purpose of the nitrifying bacteria inhibited control is to determine if the inhibitor is impairing the uptake rate of the heterotrophic bacteria.

A similar procedure is used to determine if the wastewater is phosphorus deficient. A known phosphorus standard is added to a Strathtox tube containing endogenous wastewater. An equal volume of water is added to a second endogenous wastewater sample that acts as the control. At test completion the Strathtox pulpandpapercanada.com

program calculates the SOURs, samples are filtered and ortho-phosphate tests conducted. If there is a significant difference in the SOURs and/or ortho-phosphate consumption, phosphorus deficiency can be occurring.

The procedure can assist WWTPs with regulatory phosphorus limits to assess whether operating phosphorus residuals are adequate. Plants with strict limits may be required to maintain ortho-phosphate residuals approaching zero to comply with regulations. This testing can be an important tool in determining whether lower phosphorus residuals are optimal.

For example, if there is no difference in the control and spiked SOURs and the bacteria have not consumed spiked phosphorus it could be concluded the ortho-phosphate residuals are adequate and the phosphorus addition rate can be maintained or possibly reduced.

This method in conjunction with anthrone polysaccharide testing can assist in reducing phosphorus costs. Although polysaccharide levels may be normal, phosphorus over-addition can occur. By conducting phosphorus SOUR/phosphorus recovery testing information can be obtained to assist in decreasing phosphorus addition.

WWTPs reducing nutrients can also utilize soluble BOD and/or discharge SOURs as an additional tool to assess nutrient deficiency.

In complete mix systems soluble BODs can be used to assist with an assessment of nutrient deficiency. Observation of lower BOD removal efficiency and higher BODs can indicate nutrient deficiency if oxygen is not limited and/or no significant influent toxicity exists. As well, elevated BODs can relate to elevated sample TSS or incomplete biological treatment.

Higher sample TSS may increase the total BOD. To determine if the BOD is elevated due to the presence of bacteria soluble BOD testing is required. If the soluble BOD is elevated it may relate to nutrient deficiency. Soluble BOD testing has WWTP optimization limitations due to the five-day delay in obtaining results.

Laboratory SOURs can theoretically provide similar information but inaccuracies exist as the lab testing does not reflect actual reactor conditions.

An alternative SOUR tool is the Strathkelvin Bioscope in-situ respirometer. The

Bioscope is a field respirometer consisting of a sectioned four meter pole with a D.O. probe enclosed within a sampling container. The probe is inserted into the wastewater and when D.O. stabilizes the sampling chamber is closed. The oxygen depletion is measured and results graphically displayed on a computer panel. At test completion the mixed liquor suspended solids (mlss) or the mixed liquor volatile suspended solid (mlvss) is inputted and an SOUR result calculated. A test is normally completed within 5 minutes.

Bioscope SOURs conducted prior to and after nutrient adjustment can provide critical nutrient optimization data. Lower SOURs indicate bacteria are maximizing BOD removal while higher SOURs indicate possible nutrient deficiency.

In-situ SOUR respirometer testing provides rapid and accurate data not obtained by other methods. With in-situ testing there is no error related to delay between sampling and testing, temperature or the test D.O. start point. In laboratory SOUR testing the sample is saturated with oxygen and D.O. readings are recorded after about 30 seconds. The decision regarding the D.O. start point introduces significant error.

With in-situ respirometry this inaccuracy is eliminated as the test commences when the D.O. stabilizes. With in-situ testing the start point is the actual reactor D.O. residual. For example if the reactor D.O. is 2 mg/L then the Bioscope test starts at this value. In laboratory SOUR testing the start point would normally be at a much higher value. This technological advancement allows personnel to obtain real time data that can assist with nutrient addition adjustments.

Conclusion

Nutrient management can be improved for many WWTPs with substantial cost savings possible. Inter-relationships between nutrients and the wastewater bacterial growth environment can be complex, requiring specialized knowledge that surpasses traditional nutrient residual monitoring and control.

Many pulp and paper aerated lagoon and activated sludge plants over-add nutrients as they are unaware of reactor nitrification and denitrification or of lower phosphorus requirements. As well, WWTPs decreasing nutrient addition March/April 2010 PULP & PAPER CANADA

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WASTEWATER may also encounter nutrient deficiency without adequate nutrient optimization tools and knowledge.

There exist significant opportunities to optimize WWTP operations through new nutrient assessment methods and technology. Nutrients requirements are site-specific with nutrient assessments important in determining potential cost savings for individual plants.

Biological Effluent Treatment, Paper Technology, August 1990, 33-55.

4. JENKINS, D., RICHARD M.G., DAIGLER G.T. Manual on the Causes and Control of Activated Sludge Bulking, Foaming and Other Solids Separation Problems, edn 3. Boca Ratan, FL, Lewis Publishers; 2003.

5. JURETSCHKO, S., TIMMERMANN, G., SCHMID, M., SCHLEIFER, K., POMMERENINGROSER, A., KOOPS, H., WAGNER, M. Combined Molecular and Conventional Analyses of Nitrifying Bacterium Diversity in Activated Sludge: Nitroscoccus mobilis and Nitrospira-Like Bacteria as Dominate Populations.

Applied and Environmental Microbiology 64(8):30423051(1998).

LITERATURE

Reference: KENNEY, R. Nutrient Optimization for Pulp and Paper Wastewater Treatment Plants – An Opportunity for Major Cost Savings, Pulp & Paper Canada 111(2):T17-T21 (Mar./Apr. 2010).

Paper presented at the PAPTAC 95th Annual Meeting in Montreal, Que., February, 3-4, 2009. Not to be reproduced without permission of PAPTAC. Manuscript received June 1, 2008. Revised manuscript approved for publication by the Review Panel September 29, 2009.

1. AUSTIN, D., LOHAN, E., VERSON, E. Nitrification and denitrification in a tidal vertical flow wetland pilot, Proceedings 2003 Water Env. Technical Conf.

2. FOSTER, M.H., KLOPPING, P.H., DAILEY, R.C., KIRKPATRICK, S.B. Using Respirometry to Evaluate the Impact of Macronutrients Application in Pulp and Paper Aerated Stabilization Basins, Proceedings 2003 Tappi Env. Conf.

3. GOSTICK, N.A. The Nutrient Requirements in

6. KENNY, R., ALMOST, S., HICKS, J. Troubleshooting Pulp and Paper Aerated Stabilization Basins for TSS and Toxicity Upsets, Proceedings, 2000 Tappi International Env. Conf., 371-381.

7. KENNY, R. Investigation of Nitrification and Denitrification Using DNA Gene Probes, 2003 Tappi Annual Conference, Portland, Oregon.

8. SLADE, A.H., ELLIS, R.J., VANDEN HEUVEL, M., STUTHRIDGE, T.R. Nutrient Minimization in the Pulp and Paper Industry: An Overview”. Wat. Sci. Tech.

50(3):111-122 (2004).

9. WAGNER, M., LOY, A. Bacterial Community Composition and Function in Sewage Treatment Systems, Current Options in Biotechnology 13(3):218-227.

Keywords: NITRIFICATION, DENITRIFICATION, NUTRIENT DEFICIENCY, RESPIROMETER, SPECIFIC OXYGEN UPTAKE, AMMONIA, NITROGEN, NITRATE, PHOSPHORUS, PULP AND PAPER, WASTEWATER, FLUORESCENCE IN SITU HYBRIDIZATION

PAPTAC ABSTRACTS

Recycle of the Oxygen Delignification Filtrate to the Recovery Cycle at Acid Sulphite Mills: Technical Feasibility

By N. Jemaa, M. Paleologou, A. Thibault, J. Sullivan and L. Beaudoin

Recyclage du filtrat de délignification d’oxygène au cycle de récupération dans les usines à bisulfite : faisabilité technique

Abstract: In acid sulphite mills the recycle of oxygen delignification filtrate to the recovery cycle can not be implemented unless sodium ions are removed. Sodium, a non-process element, causes plugging of the flue gas passages in the recovery furnace.

We used cation-exchange technology and removed 99% of the sodium ions from oxygen delignification filtrates. The recovery of BOD and COD was higher than 90%. Recycling the sodiumfree filtrate to the recovery cycle offloads the effluent treatment system, increases steam production and reduces fresh water consumption.

Paper presented at the PAPTAC 95th Annual Meeting in Montreal, Que., February 3-4, 2009.

Keywords: SULPHITE MILLS, DELIGNIFICATION, FIL TRATES, RECYCLING, RECOVERY, ACID PULPING, CLOSED CYCLE, ION EXCHANGE. Full manuscript available at www.paptac.ca.

24

PULP & PAPER CANADA March/April 2010

(Full peer-reviewed manuscripts available at www.paptac.ca)

TMP from Blends of Wood Species – Implications for Control

By I. Omholt, K.B. Miles, M. Stacey, and D. Dranfield

PTM provenant d’un mélange d’espèces de bois – implications et contrôle

Abstract: This paper explores TMP produced from chip blends of wood species, two at a time. Black spruce, jack pine, balsam fir, western hemlock, and lodgepole pine were included in the pilot trials. The pulp properties at a given CSF often followed linear or second-order trends between the pure species. The results are used to illustrate how unusual combinations of properties may appear when variations in energy and pulp properties are caused by varying species composition. This represents a challenge for the pulp quality control system.

Paper presented at the PAPTAC 95th Annual Meeting in Montreal, Que., February 3-4, 2009.

Keywords: PILOT TRIAL, TMP, BLENDS, SOFTWOOD SPECIES, SPRUCE, FIR, PINE, HEMLOCK, PULP QUALITY, SPECIFIC ENERGY, CONTROL. Full manuscript available at www.paptac.ca. pulpandpapercanada.com

MECHANICAL PULPING

Low Consistency Refining of Wood Shavings

By T. Kang, G. Soong, J.A. Olson, and D.M. Martinez

Abstract: This study examines the possibility of low consistency (LC) refining of wood shavings to replace the energy intensive high consistency (HC) refining of chips. The study demonstrated that LC refining of wood shavings required significantly less energy to reach the same freeness and paper strength as high consistency refining of wood chips, but the maximum paper strength of LC refined wood shavings was lower.

Further advantages of using LC refining of shavings are increased light scattering coefficient and brightness of paper.

A

s electrical energy costs­ continue to rise with increasing demand and with the increasing shortage of high quality, long-fibred softwood chips, the future of thermo-mechanical pulping (TMP) using energy-intensive conventional, high consistency disc refiners is far from certain. In the last 30 years, since mechanical pulp strength has been sufficient to completely replace kraft pulp in most high quality paper grades, there have been a large number of studies that have looked at means of producing high strength pulp using lower energy. However, the average specific energy used to make mechanical pulps has typically increased over this time.

One strategy of reducing energy is the increased use of low consistency (LC) refiners.

Conventional TMP chip refining is done at high consistencies of 25% to 40%, while conventional post refining is done at various consistencies ranging from 3 % to 40 %, but is most commonly done at low consistency in the 3-4% range. It is well known that the LC pulp refining consumes less energy than high consistency (HC) refining to achieve the same quality change [1-3].

As energy costs become higher, LC refining is gaining more attention as possible means of replacing some of HC refining energy used in the manufacture of high quality papermaking fibres [4-6]. The results of these attempts have shown the reduction of energy consumption up to 30%.

Wood chips are the main raw material in HC mechanical pulping processes, and saw mill residues such as sawdust and planar shavings can be mixed with wood chips for the pulping process [7]. Even wood shavings alone can be used in HC TMP pulping [8], which showed about 25 % reduction in refining energy. Initial fibre pulpandpapercanada.com

length of these wood shavings was longer than that of conventional wood chips, but the final fibre length of wood shavings after HC refining were shorter than wood chips.

Wood shavings are thinner and lighter than wood chips and can be fed directly through an LC refiner without HC refining. In effect much of the defibering is done in the veneering or shaving process. Chemical pretreatment such as sulfonation [9-10] or alkaline peroxide pretreatment (APMP) [11-14] might be needed to soften the lignin resulting in easier fibre separation during LC refining, reducing refining energy. APMP seems to be the better pretreatment due to better pulp quality, sulphur free environment and lower energy consumption over conventional sulfonation [11, 15].

In this research, we explore the use of readily available wood materials and novel mechanical pulping methods to complete the initial defibering of wood to produce a feed material that is suitable for the more energy efficient LC refiner.

The objectives of the study were to evaluate whether wood shavings can be used for LC refining at the primary stage after chemical pretreatment, and to examine the potential energy savings with wood shavings compared to wood chips.

T. KANG formerly Pulp and Paper Centre, University of British Columbia, Vancouver B.C. Now Winstone Pulp International. Ohakune, New Zealand

G. SOONG Pulp and Paper Centre, University of British Columbia, Vancouver B.C.

J.A. OLSON Pulp and Paper Centre, University of British Columbia, Vancouver B.C.

METHODS AND MATERIALS

Raw material Conventional wood chips and shavings (85% pine, 10% spruce, 5% fir) were obtained from a pulp mill in the interior of British Columbia.

Thicknesses of wood shavings are approximately 0.2 to 0.5 mm, and thicknesses of wood chips are about 3 to 5 mm. Fig.1 shows wood shavings and wood chips used in the study.

D.M. MARTINEZ Pulp and Paper Centre, University of British Columbia, Vancouver B.C.

March/April 2010 PULP & PAPER CANADA

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MECHANICAL PULPING TABLE I. Pulp properties.

Fig. 1. Wood shavings (top) and wood chips (bottom). Scale bar of 10 mm.

Chemical Pretreatment Both wood chips and shavings are separately impregnated with 0.5% diethylenetriaminepentaacetic acid (DTPA) for 60 min at 60°C at a consistency of 10%.

After washing, they were atmospherically steamed for 20 min, and then they were impregnated with 6% sodium hydroxide (NaOH), 4% hydrogen peroxide (H2O2), 0.05% magnesium sulphate (MgSO4), 1% sodium silicate (Na2SiO3) and 0.5% DTPA for 60 min at 70°C at a consistency of 20%. After chemical pretreatment, the pH was 11.1-11.5. The pretreated wood shavings and wood chips were then directly fed through a refiner.

Refining A Sprout-Waldron 305 mm atmospheric single disc refiner (Koppers Co. Inc., Muncy, USA) equipped with D2A507 Ni Hard plates was used for all refining runs. Wood chips and wood shavings were separately refined at 21-22% consistency (referred to as HC refining), and the shavings were also refined at 5% consistency (referred to as LC refining).

After refining, the pulp discharged from the refiner was neutralized with H2SO4.

26

Raw material

Refining consistency (%)

Net refining energy (kWh/t)

CSF (ml)

Fibre length (mm)

Bulk (cm3/g)

Bauer McNett fractions (%) R48

Bauer McNett fractions (%) R200

Bauer McNett fractions (%) P200

Wood chips

22%

0 4163 5600 6297 7040

– 552 484 321 218

2.70 2.10 2.07 2.03 1.95

– 3.4 3.1 2.9 2.5

– 68.5 – 66.3 60.8

– 12.2 – 13.7 14.0

– 19.3 – 20.0 25.2

Wood shavings

5%

1657 2520 2904

246 177 163

1.16 1.10 1.12

2.9 2.8 2.8

49.2 50.2 56.5

30.1 30.0 26.7

20.7 19.9 16.9

Wood shavings

21%

0 1148 2042 2852 4312

– 290 229 143 96

1.49 1.07 1.13 1.14 1.10

– 3.0 2.9 2.7 2.4

– 49.9 – 45.5 39.0

– 27.6 – 31.7 30.2

– 22.5 – 22.8 30.8

Measurements The pulps were hot disintegrated and screened on a screen (0.15 mm slots) before pulp testing. All pulp and paper samples were tested according to standard methods. Fibre length and coarseness were measured using the fibre quality analyzer (OpTest Equipment, Hawkesbury, Canada). Coarseness measurements of the mechanical pulp samples were performed on the P14/R28 Bauer McNett fractions.

RESULTS AND DISCUSSION

The initial fibre length of wood shavings obtained from the pulp mill is quite shorter than that from wood chips. This is shown in Fig. 2. A shorter fibre length was expected because of the smaller dimensions of wood shavings. A longer fibre length of wood shavings can be achieved using a specially designed knife [8, 16], and fibres of these shavings were deformed highly without reducing fibre length. Fibre length of HC refined wood chips was reduced by 22% at a refining energy of 4163 kWh/t, while that of HC refined wood shavings was reduced by 26% at a refining energy of 4312 kWh/t. The fibre length of LC refined wood shavings was assumed to be similar to that of HC refined wood shavings at a given refining energy level. Although the relative initial fibre length of wood shavings is shorter in this study, the reduction ratio of fibre length by refining is similar regardless of raw materials and refining consistency. If the initial fibre length of wood shavings is longer or similar to that of wood chips, the final fibre length may be similar to that of

PULP & PAPER CANADA March/April 2010

wood chips. This implies that a specialized shaving process designed to preserve fibre length may yield an LC refined pulp with much longer fibre length.

The freeness of both wood shavings and wood chips decreased as refining energy increased, as shown in Fig. 3 and Table I, but at a given freeness, there was a significant difference in refining energy between wood shavings and wood chips.

The freeness of HC refined wood shavings reaches 96 ml at 4312 kWh/t, while that of HC refined wood chips reaches to 552 ml at a similar refining energy level. In other words, wood chips required more energy to reach the same freeness than wood shavings. A similar response to refining of both wood chips and wood shavings for HC refining was shown earlier by Viforr & Salmén [8]. For wood shavings, there was no difference in freeness and energy relationship between LC and HC refining although LC refining was expected to require lower energy than HC refining.

Fig. 4 shows the changes in the coarseness of the fibre fraction (P14R28) as a function of refining energy. Fibre coarseness of both HC and LC refined wood shavings is higher in the lower range of refining energy, and fibre separation from wood shavings does not seem to be as efficient as wood chips. The reduction of coarseness with refining energy is similar for both LC and HC refined wood shavings. A higher coarseness of wood shavings with large middle fractions both from HC and LC refining (Table I) indicates that fibre cutting seems to be a dominant mechanism in refining of wood shavings, pulpandpapercanada.com

PEER REVIEWED

Fig. 2. Fibre length as a function of refining energy.

Fig. 3. Freeness as a function of refining energy.

Fig. 4. Coarseness as a function of refining energy. P14R28 fraction used.

Fig. 5. Tensile strength as a function of refining energy.

Error bars represent the 95% confidence interval.

which is not an ideal mechanism for fibre development.

Tensile strength improvement is proportional to the refining energy applied.

This is shown in Fig. 5. Regardless of the differences in refining consistency, all points of tensile strength of wood shavings are placed almost on the same straight line as a function of refining energy, but there is a difference in tensile strength improvement between wood shavings and wood chips. At a given refining energy, tensile strength of wood shavings is higher than that of wood chips, but the maximum tensile strength of wood shavings is limited probably due to shorter fibre length. A similar trend is seen for tensile stiffness as pulpandpapercanada.com

shown in Fig. 6.

Fig. 7 shows that light scattering coefficient for wood shavings is higher than wood chips as tensile strength increases.

Refining of both wood chips and wood shavings at higher consistency increases the light scattering coefficient slowly, while LC refining of wood shavings increases light scattering coefficient faster. The difference between wood shavings and wood chips in HC refining can be explained by the amount of fines and middle fractions.

The decrease in bulk as shown in Table I can be the reason for their slower increase in light scattering coefficient. For LC refined wood shavings, the bulk remains almost constant, while the amount of the

middle fraction is higher than that of wood chips.

Brightness of wood shavings is much higher than wood chips as shown in Fig. 8. Thinner thickness of shavings will likely be favourable for alkaline peroxide pretreatment. It was shown that chemical penetration and diffusion rate is a function of chip thickness [17-18]. For wood shavings, bleaching efficiency is better for LC refining. This may be due to more efficient mixing between H2O2 and wood shavings at lower consistency.

Chip dimensions, such as chip thickness, are an important parameter in determining energy consumption in refining.

More energy is required to fracture a wood March/April 2010â&#x20AC;&#x192; PULP & PAPER CANADAâ&#x20AC;&#x192;

27

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MECHANICAL PULPING

Fig. 6. Tensile stiffness as a function of refining energy.

Error bars represent the 95% confidence interval.

chip with a higher thickness, and to refine thicker chips [19-20].

The energy consumption for producing wood shavings was found to be as low as 5 kWh/t while that for wood chips is in the range between 15-25 kWh/t [16].

Wood shavings have several advantages over conventional wood chips. Firstly, less energy is required to refine and bleach wood shavings having thinner thickness compared to conventional wood chips. Secondly, fibres deformed during producing wood shavings would improve fibre separation and fibre flexibility during refining. This preliminary study indicates that readily available wood material such as wood shavings used in LC refining has the potential to save both energy and bleaching costs. However, commercially available wood shavings used in this study have a shorter fibre length, and fibre cutting caused by LC refining was inevitable. Fibre length of wood shavings can be preserved using a specially designed knife and shaving geometry.

Alternative pretreatments such as steam explosion or microwave or biological treatment should be considered as a means to soften wood shavings for LC refining. Future work will also look at producing different types of wood shavings designed for LC refining.

CONCLUSIONS

Wood shavings pretreated with alkaline peroxide were directly fed through an atmospheric refiner at a consistency of 5%. HC and LC refining of wood shavings showed a better reduction in refining energy at a given freeness than HC refining of wood chips, and no difference in the relationship of refining energy and freeness was found between LC and HC refining of wood shavings. LC refining of wood shavings was found to reduce the mean fibre length of shavings in a similar ratio with HC refining of shavings and wood chips. The relatively high coarseness of LC refined wood shavings was reduced slightly as a function of refining energy.

The maximum obtainable tensile strength for LC refined shavings is lower than that of HC refined chips. At a given tensile strength, lower refining energy was required for LC and HC 28â&#x20AC;&#x192;

PULP & PAPER CANADAâ&#x20AC;&#x192; March/April 2010

Fig. 7. Light scattering coefficient vs. tensile strength.

Fig. 8. ISO brightness as a function of refining energy.

refining of wood shavings compared to HC refining of wood chips. A great advantage of using LC refining of shavings over wood chips is increased light scattering and brightness of paper.

ACKNOWLEDGEMENTS

This work was funded by the Natural Sciences and Engineering Research Council of Canada through the Collaborative Research and Development program and through the support of our partners BC Hydro, Paprican, Catalyst Paper, Howe Sound Pulp and Paper, West Fraser Quesnel River Pulp, Canfor, Andritz, Arkema, Honeywell, WestCan Engineering, Advanced Fiber Technologies, Ontario Power Authority and CEATI international.

LITERATURE

1. MUSSELMAN, R, LETARTE, D., SIMARD, R. & LACHANCE, C., Third stage low consistency refining of TMP for newsprint/directory grades, Proc. Appita Conf., p.363-368 (1996).

pulpandpapercanada.com

PEER REVIEWED 2. MUENSTER, H., FERRITSIUS, O., LECOURT, M. & PETIT-CONIL, M., Energy savings in TMP by high temperature LC/MC refining, Proc. Intl. Mech. Pulp.

Conf., p.213-223 (2005).

3. SABOURIN, M., Minimizing TMP energy consumption using a combination of chip pre-treatment, RTS and multiple stage low consistency refining, Proc. Intl.

Mech. Pulp. Conf., CD-ROM (2007).

4. HAMMAR, L-Å, HTUN, M. & SVENSSON, B., A two-stage refining process to save energy for mechanical pulps, Proc. Intl. Mech. Pulp. Conf., p. 257-262 (1997).

5. XU, E.C., KOEFLER, H. & ANTENSTEINER, P., Some latest developments in alkali peroxide mechanical pulping, Part 2: Low consistency secondary refining, Pulp Paper Can. 104(10):47-51 (2003).

6. ERIKSEN, O. & HAMMAR, L-Å., Refining mechanisms and development of TMP properties in a lowconsistency refiner, Proc. Intl. Mech. Pulp. Conf., p.

62-75 (2007).

7. LEASK, R.A., A potential use of a wider range of raw material in thermomechanical pulping, Tappi J. 60(12):82-87 (1977).

8. VIFORR, S. & SALMÉN, L., From wood shavings to mechanical pulp- a new raw material?, Nord. Pulp Paper Res. J. 20(4):418-422 (2005).

9. ATACK, A., HEITNER, C. & KARNIS, A., Ultra-high yield pulping of eastern black spruce, Svensk Papperstidn. 81(5):133-141 (1980).

10. AXELSON, P. & SIMONSON, R., Thermomechanical pulping with low addition of sulfite. Part 1.

Effects of mild sulfite treatment of spruce chips prior to defibration, Svensk Papperstidn. 85(15):R132-R139 (1982).

11. BOHN, W. & SFERRAZZA, M., Alkaline peroxide mechanical pulping, a revolution in mechanical pulping, Proc. Intl. Mech. Pulp. Conf., p. 184-200 (1989).

12. YUAN, Z., HEITNER, C. & MCGARRY, P., Evaluation of the APMP process for mature and juvenile loblolly pine, Tappi J. 5(7):24-32 (2006).

13. BIAN, Y., NI, Y., YUAN, Z, HEITNER, C. & BEAULIEU, S., Improving TMP rejects refining through alkaline peroxide pretreatment for value-added mechanical papers, Tappi J. 6(3):24-32 (2007).

14. ZANUTTINI, M. & MARZOCCHI, V., Alkaline chemi-mechanical pulp from poplar. Relationship between chemical state, swelling and papermaking properties, Holzforschung. 57(5):489-459 (2003).

15. XU, E.C. & SABOURIN, M.J., Evaluation of APMP and BCTMP for market pulps from South American eucalyptus, Tappi J. 82(12):75-82 (1999).

16. HEDBLOM-HUE, S., MALM, Å & SALMÉN, L., Shear cut chips for mechanical pulping with lower energy demand, Proc. Intl. Mech. Pulp. Conf., p.

Résumé: La présente étude porte sur la possibilité de raffinage à faible concentration (FC) des rabotures et des copeaux au lieu du raffinage haute concentration (HC) des copeaux à forte consommation d’énergie.

L’étude a démontré que le raffinage FC des rabotures de bois exigeait beaucoup moins d’énergie pour obtenir le même indice d’égouttage et la même résistance du papier que le raffinage HC des copeaux de bois, mais la résistance maximale du papier fabriqué à partir de rabotures raffinées à faible concentration était moindre. Le raffinage FC concentration des rabotures permet aussi d’améliorer le coefficient de diffusion de la lumière et la blancheur du papier.

Reference: KANG, T., SOONG, G., OLSON, J.A., MARTINEZ, D.M. Low Consistency Refining of Wood Shavings, Pulp & Paper Canada 111(2):T22-T26 (Mar/Apr 2010). Paper presented at the 27th International Mechanical Pulping Conference, Sundsvall, Sweden, June 1-4, 2009. Not to be reproduced without permission of PAPTAC. Manuscript received August 31, 2009. Revised manuscript approved for publication by the Review Panel November 9, 2009.

Keywords: LOW CONSISTENCY REFINING, HIGH CONSISTENCY REFINING, WOOD SHAVINGS, WOOD CHIPS, ENERGY SAVING

(Full peer-reviewed manuscripts available at www.paptac.ca)

Higher Energy Performance at AbitbiBowater Kénogami Mill Using Data Mining

By G. St-Pierre, M.G. Fairbank, S. Lafourcade

Meilleure performance énergétique à l’usine d’AbitibiBowater – Kénogami grâce à l’exploration des données

Abstract: The AbitibiBowater Kénogami mill has made a lot of efforts in the past years to improve their energy efficiency through measurement system and good energy practices. To achieve and sustain higher energy performance, the mill worked together with Pepite Technologies Inc. to develop an innovative energy management step-by-step approach. Several data mining tools have been implemented to troubleshoot root causes of energy variations and to build model-based KPIs and smart alarms to sustain high performance. This approach helps the mill to save $600,000 per year without any extra investment.

Paper presented at the PAPTAC 95th Annual Meeting in Montreal, Que., February 3-4, 2009.

Keywords: ENERGY EFFICIENCY, COST REDUCTION, TMP REBOILER OPTIMIZATION, SMART MONITORING, DATA MINING, INTELLIGENT MANUFACTURING. Full manuscript available at www.paptac.ca. pulpandpapercanada.com

143-148 (2001).

17. JIMENEZ, G., CHIAN, D.S., MCKEAN, W.T. & GUSTAFSON, R.R., Experimental and theoretical studies to improve pulp uniformity, Proc. TAPPI Pulp.

Conf., p. 49-53 (1990).

18. SVEDMAN, M., TIKKA, P. & LUHTANEN, M., Effects of softwood morphology and chip thickness on pulping with a displacement kraft batch process, Tappi J. 81(7):157-168 (1998).

19. HOEKSTRA, P.L., VEAL, M.A., LEE, P.F. & SINKEY, J.D., The effects of chip size on mechanical pulp properties and energy consumption, Tappi J. 66(9):119-122 (1983).

20. ESKELINEN, E., HU, S.H. & MARTON, R., Wood mechanics and mechanical pulping, Appita J. 36(1):32-38 (1982).

PAPTAC ABSTRACTS

Effect of Variability on the Thermal Efficiency of a Kraft Mill Evaporation Unit

By R.P. Pinto, E. Espejel, M. Perrier, and J. Paris

L’effet de la variabilité sur l’efficacité thermique de l’unité d’évaporation dans une usine de pâte kraft

Abstract: The effect of variability on the black liquor evaporation unit thermal efficiency was studied. The multiple effect evaporators thermal efficiency was low during the summer because of lack of steam flow adjustment coupled with large variability. This was attributed to periodic operation of the High-Solids-Concentrator and fast dynamic variations caused by inadequate unit control of the black liquor outlet flow. It was estimated that approximately 12% steam could be saved through proper control of heat balance and stabilization of the black liquor outlet flow.

Paper presented at the PAPTAC 95th Annual Meeting in Montreal, Que., February 3-4, 2009.

Keywords: BLACK LIQUOR EVAPORATION, MULTI PLE EFFECT EVAPORATORS, THERMAL EFFICIEN CY, VARIABILITY Full manuscript available at www.paptac.ca.

March/April 2010

PULP & PAPER CANADA

29

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HEAT RECOVERY

50% Reduction in Thermal Energy Usage at Alberta Newsprint

By S. Singh, C. Mills, and A. World Abstract: In 2001/02, ANC’s natural gas usage for thermal energy demand was over one million GJ annually. To reduce the demand of thermal energy, there have been number of projects implemented at ANC in last several years such as: improving heat recovery in start-up-scrubber, redesigning of the heat exchangers network, installing reverse osmosis to reduce blow down from boilers, installing combustion optimization control for boiler operation and recovering heat from various waste streams. Various systems were also put in place for monitoring natural gas consumption on instantaneous, daily and monthly bases. By 2007/08, our yearly natural gas usage was a little over 500,000 GJ which was approximately 50% lower than in 2001/02.

P

ulp and paper making is a ­capital-, energy- and manpower-intensive process. Among all the pulping processes, the thermomechanical pulping (TMP) process is the most electrical energy intensive for chip refining. Significant heat is generated in the chip refining process which in turn is used to meet the large demand of mill thermal energy either by direct heating or by producing clean low pressure steam (to be called steam hereafter) in the reboiler.

Therefore, the cost of purchased thermal energy (natural gas, propane, coal, hog fuel, etc.) is much lower than the electrical energy cost. At Alberta Newsprint Company (ANC) we use natural gas to meet thermal energy demand, including in the generation of supplemental steam from our package boilers.

However, in view of the rising cost of natural gas from $4.34 per GJ in 2001 to over $8.00 per GJ in 2008 and over one million GJ of yearly usage, it was prudent for us to thoroughly examine our thermal energy requirements. Our benchmarking to other mills [1] and the theoretical requirement of the thermal energy of a model newsprint mill from 100% TMP [2] revealed that there was an opportunity to significantly reduce our thermal energy usage (Fig. 1).

Baseline and Monitoring

In an industrial environment, in order to demonstrate the savings, it is extremely important to clearly establish a baseline of energy usage before implementing any project. Unlike electrical energy, there are not very many local measurements of natural gas usage in the mill. Due to this limitation, other measurements such as steam flow, temperature, etc., are used to calculate the savings in thermal energy inputs. At ANC, in conjunction 30

PULP & PAPER CANADA March/April 2010

with local measurements, we also tracked our total natural gas usage since most of the projects were large enough to affect the total mill usage.

The chosen baseline period was from October 1, 2001 to September 30, 2002, a 12-month period immediately prior to the implementation of the first major project. The natural gas usage during this period was 1,080,425 GJ or 4.22 GJ per tonne of paper (Table I). The savings were calculated on 12-month basis. For tracking and monitoring, the natural gas usage was monitored on real time, daily and monthly bases.

Thermal Energy Reduction Projects

Since 2002, a number of projects have been implemented to reduce thermal energy usage at ANC. The source of thermal energy at ANC is the natural gas. The descriptions of the key projects are outlined below.

Project 1: Converting the Start-Up-Scrubber to Atmospheric Condenser (October 2002) At ANC, during the starting-up of a refiner line, the generated steam from refiners is sent to the start-up-scrubber (SUS). Once this steam is directed to the reboiler, only excess refining steam goes to the SUS. The primary purpose of the SUS is to remove the fibers before the steam was vented to atmosphere.

The objective of Project 1 was to recover heat from various vent steams and utilize it to heat mill water in order to reduce the amount of steam needed for this application. Under this project, the SUS was converted to an atmospheric waste steam condenser. Prior to this project, there was no waste heat recovery in the SUS. The scrubber circulation pump was upgraded to 7,000 litres per minute (lpm) from 1,000 lpm based on the flow required

S. SINGH Alberta Newsprint Co., Whitecourt, Alta.

C. MILLS Alberta Newsprint Co., Whitecourt, Alta.

A. WORLD formerly Alberta Newsprint Co., Whitecourt, Alta. pulpandpapercanada.com

PEER REVIEWED

Fig. 1. Comparison of ANC thermal energy usage with other newsprint mills from 100% TMP furnish [2].

to capture 15 tonnes per hour (t/h) of atmospheric saturated steam with a water temperature rise of 20°C. Several additional spray nozzles were added in the header as shown in Fig. 2. The following streams were directed to the SUS: • Reject refiner excess dirty steam, • Reboiler non condensable vent, • Flash steam from plug screw feeder (PSF) sump, • Part of refiner steam, • Part of reboiler foul condensate, • Reboiler excess dirty steam.

Two spiral heat exchangers (#1 and #2, Fig. 2) were added to recover the heat from the SUS foul condensate to heat the mill water to be used in the paper machine shower water.

This project was implemented in October 2002. As shown in Fig. 3, the steam demand for water heating on booster heat exchanger dropped from 15.5 t/h to 9.2 t/h. The savings achieved were 180,000 GJ per year or 0.73 GJ/t. Based on the natural gas price at the time, the payback of this project was about one year.

The steam demand for stock heating was also reduced from 16.6 t/h to 13.5 t/h as paper machine hot water shower temperature was raised to 55°C from 50°C.We were also able to maintain the high temperature of shower water all the time.

Project 2: New Heat Exchanger Network (December 2004) The existing heat exchanger network was not performing at its optimal level as shell and tube exchangers were severely fouled on the cold water side with no access for cleaning. The overall heat transfer coefficients on these heat exchangers were very low and we were experiencing increasing tube failures. We contracted an engineering company to conduct a study for improving utilization of waste heat from thermomechanical pulping to reduce the steam usage for both stock and water heating.

We took the approach of simultaneously reducing water and steam usage [3]. An analysis of heating and cooling requirements was completed employing the principles of pinch analysis to determine how the mill may be able to utilize the waste heat more effectively. A new heat exchanger network was designed to recover the maximum practical amount of heat. A simplified dynamic simulation of the mill was also developed to provide additional confirmation of the effectiveness of the heat exchanger network and to predict the effect of various changes on the dynamic behavpulpandpapercanada.com

Fig. 2. Start-up-scrubber as atmospheric condenser.

Fig. 3. Steam usage for stock and water heating.

ior of the mill.

Figure 4 shows the heat exchanger network prior to the project. Constant temperature of the streams going to effluent from the plug screw feeder (PSF) filtrate and TMP effluent were maintained by two shell and tube heat exchangers (#3 and #4, Fig. 4) by transferring heat to the mill water. The combined mill water from these two heat exchangers was fed to a third shell and tube heat exchanger (#5) to extract the heat from the reboiler foul condensate of 140°C. The warm water from this heat exchanger was stored in a warm water tank and was further heated before using on the paper machine showers by a booster shell and tube heat exchanger (#6) by employing steam. The cooled reboiler foul condensate was sent to the reject refining system. There were also three spiral heat exchangers installed in last few years. One on the paper machine (#7) was to maintain the head box stock temperature at 60°C by heating silo white water with steam. The steam demand on this heat exchanger was as high as 30 t/h at times with an average of 13.5 t/h (Fig. 3). The other two spiral heat exchangers (#1 and #2) were installed in 2002 during Project March/April 2010 PULP & PAPER CANADA

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Fig. 4. Old heat exchanger network prior to Project 2.

1 to heat mill water by extracting heat from various vent steams in the atmospheric condenser. The heated water from these heat exchangers was sent to the warm water tank while the cooled foul condensate was processed in the reject refining system. The drawbacks of the existing network were: • The system was designed to maintain constant effluent temperature and hence produced excessive warm water at times which had to be sewered during summer months when mill water storage temperatures were high. Unfortunately, the temperature of the combined effluent was still varying depending on the other process conditions such as over flow of white water, etc.

• The cold mill water (avg. temperature ~10°C) was used for producing warm water instead of utilizing higher temperature water (~20°C) available from the cooling water collecting tank.

• There was still a large amount of steam usage for both stock and water heating (Fig. 3).

Keeping in mind the deficiencies of the current network and the fact that having a constant effluent temperature is no longer a requirement, a new system was designed by applying pinch principles [3]. The modified network of heat exchangers is shown in Fig. 5. The new network was used for heating both stock as well as water.

Stock Heating As indicated earlier, there was a very high steam demand for spiral heat exchanger #7 for silo white water for stock heating.

To reduce this demand, an additional spiral heat exchanger #10 was installed in parallel with #7 to heat white water using reboiler foul condensate of 140°C. The steam demand on the #7 heat exchanger dropped to a minimum of 2.0 t/h during full TMP production. This heat exchanger was still needed to provide heating during curtailment or the periods of no TMP production.

Please note that, since the TMP plant is the main source of waste heat, curtailing TMP production also reduces the availability of waste heat for thermal demand.

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PULP & PAPER CANADA March/April 2010

Fig. 5. New heat exchanger network after Project 2.

Fig. 6. Yearly natural gas usage at ANC.

able with the SUS system and that availability will increase with reduced demand of water usage. Another spiral heat exchanger (#11) was installed to heat white water being used for dilution in the paper machine cleaners by using foul condensate of 90°C from the SUS. The purpose of this was to raise the temperature of white water in the machine inner loop to further reduce steam in silo heat exchanger #7. As shown in Fig. 3, the steam usage for stock heating was reduced to 4.6 t/h from 13.5 t/h.

Mill Water Heating There was still a substantial use of steam in the booster heat exchanger #6 to maintain the hot water temperature at 55°C for paper machine showers. The shell and tube heat exchangers on PSF filtrate and TMP effluent were replaced with new spiral heat exchangers #8 and #9 respectively with larger thermal capacity.

The source of warm water preparation was switched from mill water to cooling water which was at least 10°C warmer than mill water. The PSF filtrate and TMP effluent heat exchangers were installed in parallel. The warm water from the PSF filtrate heat exchanger was sent directly to the warm water tank while warm pulpandpapercanada.com

PEER REVIEWED water off the TMP effluent heat exchanger was further heated by the existing two SUS spiral heat exchangers (#1 and #2) before sending it to the warm water tank. The total warm water flow was varied based on paper machine demand instead of effluent temperature. Even though some of the waste heat which was previously used for heating mill water was diverted for heating stock (#11), the steam demand for mill water heating on booster heat exchanger #6 dropped further to 7.5 t/h from 9.2 t/h after the new heat exchanger network became operational (Fig. 3). Apart from new heat exchangers, the reduction in steam usage was primarily due to a) utilizing cooling water instead of mill water, and b) by not heating more water than needed.

After optimization of the all the heat exchangers in the network, we achieved a yearly saving of 200,000 GJ in 2007/08, which was in excess of 25% of total mill demand. On a per tonne basis the reduction was 0.80 GJ. The simple payback of this project was about two years. After implementation of Project 1 and 2, the steam demand was reduced from 16.6 t/h to 4.6 t/h for stock heating and from 15.5 t/h to 7.5 t/h for water heating (Fig. 3).

Project 3: Additional Reboiler (November 2005) During full TMP production, we were not able to process all the refiner steam to the reboiler due to its capacity limitation and also due to a very high pressure drop.

Dropping clean steam pressure from 250 to 225 kPa helped to process more refiner steam in the reboiler. However, in early 2005, we saw a significant drop in steam generation from the reboiler. Upon inspection we discovered some physical misalignment of tubes in the reboiler. Since steam generation never improved from this reboiler, we installed another smaller reboiler to produce 30 t/h of steam during the “TMP Production Increase Project” in 2005 [4]. The estimated savings in natural gas were 40,000 GJ annually.

Project 4: Heat Recovery from Grit Cleaner Reject (March 2007) The new spiral heat exchanger for PSF filtrate in Project 2 (#8 in Fig. 5) did not achieve the desired heat recovery due to severe plugging and scaling. This was primarily due to variable and insufficient flow of filtrate as this flow varies dependpulpandpapercanada.com

ing on the TMP production rate. At lower production rates, the flow was not enough to keep the heat exchanger clean. After implementation of the “TMP Production Increase Project” in 2005, the temperature and flow of the grit cleaner reject was increased making it suitable for heat recovery. This water was collected along with PSF filtrate and fed through this heat exchanger. After implementing this project in 2007, the average flow of the hot stream was increased to over 1000 lpm from 425 lpm. The heat recovery was also improved significantly as temperature drop across the heat exchanger on the hot side was increased to 35°C from 20°C. This project helped achieve the heat recovery from PSF filtrate in Project 2 as well as additional heat recovery from the grit cleaner reject. The yearly additional savings from grit cleaner heat recovery were 15,000 GJ. Project 5: Boiler Water Treatment by Reverse Osmosis (Jun 2007) The blow down rates on our boilers were significantly high despite the high conductivity in boiler drum of 2500 μmhos.

It was primarily due to very basic treatment of boiler feed water by resin zeolite softener. Chemicals were also added for pH control, dissolved oxygen removal and scale control. In 2007, a four stage reverse osmosis (RO) spiral membrane system was installed with a permeate flow of 1000 lpm at a 75% recovery rate. The conductivity of permeate was reduced to 20 μmhos from the feed conductivity of over 300 μmhos.

The blow down rate has dropped to the minimum (from 20% to less than 5% control valve opening) due to low boiler

feed water conductivity after installing RO system. The reduction in natural gas usage was estimated to be 30,000 GJ/year.

Project 6: Boiler Combustion Control (April 2008) This project was to reduce excess O2 (air) in our packaged boiler stack while reducing the NOx emission. Sensors were installed to measure carbon monoxide (CO) in the flue gases. These sensors were used for controlling the amount of excess air. The excess air was reduced from 4% to 1%. The CO control range was 50 to 200 parts per million. The savings from this project was estimated to be 15,000 GJ annually.

Miscellaneous Projects There were several other initiatives implemented to avoid the waste of heat such as routine maintenance of steam traps, insulation of steam valves and avoidance of overflow of warm water and white water tanks. Also, the reboiler tubes were cleaned on a yearly basis to maximize steam generation. With these projects and with more awareness in the mill for managing thermal energy, we estimated a yearly saving of approximately 40,000 GJ. Water Reduction A significant amount of thermal energy is needed to heat the mill water. For example, the energy needed to heat the incoming water flow of 10,000 lpm from 10°C to 50°C is approximately 1 million GJ annually. The energy demand increases in the winter months when incoming water temperature dips below 1°C while the outgoing effluent temperature remains relatively constant between 50 and 55°C.

TABLE I. Yearly natural gas usage and savings with various projects Base Line Period

Oct 1, 2001 to Sept 30, 2002

Natural Gas Usage during Base Line, Total GJ Natural Gas Usage during Base Line, GJ/tonne

1,080,425 4.22

Natural Gas Usage after Project Implementations Year 2002/03 2003/04 2004/05 2005/06 2006/07 2007/08 Total GJ 833,474 824,588 725,276 642,895 712,690 558,700 GJ/tonne 3.30 3.07 2.75 2.62 2.90 2.25 Annual Savings, GJ Start up Scrubber 180,000 180,000 180,000 180,000 160,000 180,000 New Heat Exch. Network 130,000 180,000 130,000 200,000 Additional Reboiler 40,000 40,000 40,000 Grit Cleaners 5,000 15,000 Reverse Osmosis 5,000 30,000 Boiler Combustion Control 15,000 Others 66,951 75,837 45,149 37,530 27,735 41,725 Total Annual Savings, GJ 246,951 255,837 355,149 437,530 367,735 521,725

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HEAT RECOVERY We have been able to reduce our water usage by around 2000 lpm in the last number of years by shutting down our deink plant, and by better white water management. There are several other projects, the mill is working on to further reduce the water usage, details of which will be covered elsewhere.

Summary of Results

due to increased energy awareness of mill personnel. Apart from significant financial benefits, these efforts are in line with our commitment to reduce our mill’s greenhouse gas emissions.

LITERATURE

1. MEUNIER, K., BRUYERE, S., PIERSON, K., DEVALERIOLA, N., WHEELER, N., MILLS, C., JOHNSON, J., SINGH, S., Energy and Deregulation at

Résumé: En 2001-2002, Alberta Newsprint Company utilisait plus de 1 million de GJ chaque année pour

As illustrated in Table I and in Fig. 6, our natural gas consumption has been reduced to 558,700 GJ in 2007/08 from 1,080,425 GJ in 2001/02. On a per tonne basis, the energy requirement was dropped to 2.25 GJ from 4.22 GJ.

Conclusions

The natural gas usage was reduced to nearly half by implementing various projects over the last 6 years. The payback of the projects ranged from a few months to 2 years. The reduction was also partly

Alberta Newsprint, Proc. 2003 International Mechanical Pulping Conference, 437(2003) 2. “Energy Cost Reduction in Pulp and Paper Industry”, monograph published by PAPRICAN 1999.

3. WEARING, J., PIERSON, K., White Water Strategies for Integrated TMP Newsprint Mills - Implementation of a Comprehensive System for Energy and Water Conservation at Alberta Newsprint, Pulp & Paper Can. 108(4):48-51 (2007) 4. SINGH, S., MILLS, C., WILD, N. W. H., Increasing Flexibility for the Time of Day Pulping at Alberta Newsprint Company, Pulp & Paper Can. 110(9):T165-T169 (2009)

combler sa demande en énergie thermique. Pour réduire cette demande, ANC a mis en œuvre divers projets au cours des dernières années : amélioration de la récupération de la chaleur du purificateur de démarrage, nouvelle conception du réseau d’échangeurs de chaleur, installation de l’osmose inversée afin de réduire la purge des chaudières, installation d’une commande pour l’optimisation du fonctionnement de la chaudière, et récupération de la chaleur de divers circuits de déchets. Des systèmes (instantané, chaque jour, chaque mois) ont aussi été mis en place afin de surveiller la consommation de gaz naturel. En 2007-2008, la consommation annuelle de gaz naturel d’ANC était d’un peu plus de 500 000 GJ, soit environ deux fois moindre qu’en 2001‑2002.

Reference: SINGH, S., MILLS, C., WORLD, A. 50% Reduction in Thermal Energy Usage at

Alberta Newsprint, Pulp & Paper Canada 111(2):T27-T31 (Mar./April 2010). Paper presented at the 95th Annual Meeting 2009 in Montreal, Que., February 3-4, 2009. Not to be reproduced without permission of PAPTAC. Manuscript received October 1, 2008. Revised manuscript approved for publication by the Review Panel Dec. 11, 2009.

Keywords: THERMAL ENERGY REDUCTION, PINCH ANALYSIS, WASTE HEAT RECOVERY, WATER REDUCTION, HEAT EXCHANGER NETWORK

INDUSTRY NEWS White Birch Paper: newsprint producer files for creditor protection

GREENWICH, CONN.—The operator of three newsprint mills in Quebec, White Birch Paper Company, has filed for creditor protection in Canada and the U.S., to improve its capital structure.

White Birch Paper is the parent company of the F.F. Soucy mill in Rivièredu-Loup, the Stadacona mill in Quebec, and Papier Masson in Gatineau. The company’s U.S. subsidiary, Bear Island Paper Company, also filed for relief under Chapter 11 of the United States Bankruptcy Code.

“This process is about fixing our capital structure,” said Christopher Brant, president. White Birch expects operations to continue as usual during and after the restructuring process.

White Birch Paper is the second largest newsprint producer in North America. It cites a decline in demand for newsprint, combined with a decline in prices, as well as the increased strength of the Canadian dollar, as having a negative impact on its business. AbitibiBowater, another large newsprint producer in North America, is also operating under bankruptcy protection.

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Sale of Fraser Papers’ specialty papers business clears all hurdles

TORONTO – Fraser Papers Inc., the Canadian Energy and Paperworkers Union of Canada, the Government of New Brunswick, and other stakeholders have agreed to the broad terms under which Fraser Papers will proceed to close the sale of its specialty papers business to a company sponsored by the secured creditors of Fraser Papers, called Newco. The agreement included proposed changes to the collective agreements at the company’s Edmundston pulp and energy complex.

The company has filed the agreement with the Ontario Superior Court of Justice, and will work with its secured creditors and Newco to close the sale of the specialty papers business before March 31, 2010.

Under the terms of the purchase agreement, the unsecured creditors of Fraser Papers will receive promissory notes and a 49% common equity interest in the new company. Brookfield Asset Management Inc., a secured creditor, has agreed to convert its secured claim into a 51% common equity interest in Newco while the Government of New Brunswick will convert its $35 million secured loan into

PULP & PAPER CANADA March/April 2010

preferred shares of the new company.

Tentative agreement between CEP and AbitibiBowater

MONTRÉAL – The Communications, Energy and Paperworkers Union of Canada (CEP) has agreed to a tentative agreement with AbitibiBowater to renew the collective agreement. This deal fulfills an essential condition towards the emergence of the company from the current restructuring process.

“We have the best possible agreement, given the precarious financial condition of the company,” says CEP president Dave Coles. “We are proud to have been able to protect retirees and to have created a new stable pension plan for the active workers. Our members will no longer have to fear the shadow of an insolvency of their plan.”

The company took off the table its proposal to terminate the pension plans, which would have reduced pension benefits by an average of 25%.

This agreement covers about 4,500 workers and 8,000 retirees from 23 AbitibiBowater locals at 12 pulp and paper mills in Eastern Canada. pulpandpapercanada.com

PROCESS CONTROL

On-line Fiber Orientation Measurement and Control

By T. Sasaki, H. Sano, J. Yamamoto, H. Todoroki, K. Ono, T. Ochi Abstract: New automatic measurement and control system for fibre orientation has been developed. In this system, the fibre orientation angles on paper surfaces are measured continuously, and the edge flow valves and slice lip actuators at the headbox are manipulated automatically to minimize the differences of fibre orientation angles between the felt and wire sides. This control has been implemented in an actual copy paper machine since the beginning of 2007 and the average degree of twist-curl has been reduced to less than half before.

I

n this paper, the methodology of the on-line fibre orientation measurement and control is presented.

There are several factors which generate the twist-curl of sheets. One of them is the chirality of wood fibres. All wood fibres have the same right-handed chirality of the cellulose fibrils in the secondary fibre wall. This chirality causes a slight bending in the same direction upon humidity changes, which is said to be the cause for twist-curl of thin papers [1]. This phenomenon occurs when the sheet specimen is very thin and narrow.

On the other hand, the difference in fibre orientation angles between felt and wire sides is also said to be the crucial factor to generate the twistcurl of sheets [2,3,4,5]. Previously, we developed the world’s first on-line fibre orientation sensor, which made it possible to measure fibre orientation on the surface of paper on both the felt and wire sides [6]. This sensor was incorporated in Yokogawa’s QCS system and through the measurement and calculation, fibre orientation angle and index profiles of both felt and wire sides are produced. The sensor was launched in 1999 and has been highly evaluated by customers.

Several earlier studies about fibre orientation control have been published [7,8,9,10]. This paper describes the necessity of both the edge flow valves and the slice lip actuators to control fibre orientation profile and the effectiveness of the feed-back control utilizing on-line fibre orientation measurement by the actual data of twist-curl.

First, we performed process analysis and bump tests of edge flow valves and slice lip actuators, and gathered considerable data that describes how fibre orientation profiles changed when the edge flow valves and the slice lip actuators were pulpandpapercanada.com

manipulated. Second, we performed fluid simulation within a headbox and thoroughly analyzed the behaviour of flow velocity vectors at the outlet of the slice lip. Third, by combining both results of the bump tests and the fluid simulation, we succeeded in developing a control algorithm based on a numerical model that describes the behaviour of fibre orientation angles when the edge flow valves and the slice lip actuators are manipulated. Finally, we incorporated the control software in Yokogawa’s QCS system and have been implementing the continuous on-line control in an actual paper machine since Feb. 2007.

T. SASAKI Paper & Web Solutions Dept., Yokogawa Electric Corp., Tokyo, Japan

H. SANO Paper & Web Solutions Dept., Yokogawa Electric Corp., Tokyo, Japan

J. YAMAMOTO Pulp and Paper Research Laboratory, Nippon Paper Industries Co., Ltd., Tokyo, Japan

H. TODOROKI Pulp and Paper Research Laboratory, Nippon Paper Industries Co., Ltd., Tokyo, Japan

K. ONO Pulp and Paper Research Laboratory, Nippon Paper Industries Co., Ltd., Tokyo, Japan

T. OCHI Pulp and Paper Research Laboratory, Nippon Paper Industries Co., Ltd., Tokyo, Japan

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Fig. 1. Principle of the fibre orientation measurement.

Fig. 2. Configuration of the fibre orientation sensor.

Fig. 3. Twist-curl

FIBRE ORIENTATION MEASUREMENT

Principle of the fibre orientation sensor The measurement principle of the fibre orientation sensor is based on the fact that light reflected by the cellulose fibres of paper surfaces has anisotropy. More specifically, the reflected light is more intensely diffused in the radial direction of fibres than in the axial direction (Fig. 1). As is illustrated in Fig. 2, the fibre orientation sensor is equipped with the infrared light source and light-detecting elements, and through special mathematical calculations, the sensor enables the on-line measurement of fibre orientation angle and index.

By mounting the fibre orientation sensors on both the felt and wire sides of paper, it becomes possible to measure the difference of fibre orientation angles between the felt and wire sides of paper. The difference of fibre orientation angles is known as the cause of twist-curl, which is quite an important quality factor, especially for copy paper.

Correlation between fibre orientation and twist-curl Paper sheet usually has so-called twosidedness, which means the difference in properties between one and the other 36

Fig. 4. Correlation between the difference of fibre orientation angles and twist-curl.

sides of the paper. If the paper sheet has strong two-sidedness in dimensional stability, the sheet can be easily curled with the change of moisture content. Consequently, copy paper is required to have less two-sidedness with regard to dimensional stability to maintain better runnability in copy machines.

One of the principal factors that generates two-sidedness of dimensional stability is the two-sidedness of fibre orientation.

The two-sidedness of fibre orientation means the difference of the felt and wire side fibre orientation angles and intensities.

Fig. 3 illustrates how the difference of fibre orientation angles causes the twist-curl.

Moreover, Fig. 4 is the results of the offline measurement of the difference of fibre orientation angles (uF-W) and the off-line measurement of twist-curl (DCL), and it represents that there is a strong correlation between the difference of fibre orientation angles and twist-curl of the paper.

DEVELOPMENT OF THE FIBRE ORIENTATION CONTROL

Process description The paper machine for the field test is

PULP & PAPER CANADA March/April 2010

equipped with a consistency profiling headbox, a hybrid twin-wire forming section, and on-line sensors for fibre orientation measurement. The width is 5600 mm, the running speed is 1000 m/min and jetto-wire ratio is 1.01.

Results of the bump tests Two actuators were examined in order to control fibre orientation angles, which were the edge flow valves and the slice lip actuators of the headbox. At first, it was examined how they influenced fibre orientation angle profiles on both felt and wire sides of paper web when the actuators were manipulated in certain quantities on the actual paper machine. The profiles of fibre orientation angles on both sides of paper were changed when the actuators were manipulated, however, the profiles shifted in the inverse directions between felt and wire sides (Fig. 5, 6).

Moreover, these results illustrated that the edge flow valve openings influenced fibre orientation angles in a broad area in the cross-machine direction from each edge of the paper machine. On the other hand, the local change of the slice lip pulpandpapercanada.com

PEER REVIEWED

Fig. 5. Results of the bump test and the numerical model (edge flow valves).

shape influenced fibre orientation angles just in the local area.

Fluid simulation within the head box The results of the bump tests merely provided the information about the responses of fibre orientation angles to the manipulations of edge flow valves and slice lip actuators. However, in order to make a precise numerical model, it was necessary to obtain information regarding velocity change in both machine- and crossdirection. Therefore, a fluid simulation within the headbox was performed using the computational fluid dynamics (CFD) technique, and precise information about velocity change when the edge flow valves and the slice lip actuators were manipulated was obtained. This information about velocity change enables the calculation of the change in fibre orientation angle profile when the edge flow valves and the slice lip actuators were manipulated.

Through the CFD analysis, the vertical distributions of velocity in machinedirection at the outlet of the slice lip were calculated as in Fig. 7. From this figure, it is presumed that the relative velocity of the fibre on the surface at felt side in machine direction to the wire is negative under this jet-to-wire ratio (=1.01). On the contrary, on the surface at the wire side, the relative velocity in machine direction to the wire is presumed to be positive under this jetto-wire ratio. This analysis explains why fibre orientation angle profiles change in the inverse direction between felt and wire sides as is shown in Figs. 5 and 6.

Effects of actuator manipulations and control strategies Through the results of the bump tests pulpandpapercanada.com

Fig. 6. Results of the bump test and the numerical model (slice lip actuators).

and the CFD analysis, the effects of each actuator manipulation are summarized as follows.

(1) Edge flow valve manipulations: The fibre orientation angle profile in a broad area in cross-direction is changed to a certain direction. As a result, the average value of fibre orientation angle in cross-direction is also able to be changed.

(2) Slice lip actuator manipulations: The fibre orientation angle profile in the local area is able to be changed by the local change of the slice lip shape. On the other hand, the average value of fibre orientation angle in cross-direction is not able to be changed because the summation of velocity change in cross-direction becomes zero.

From these analyses, the control strategy was constructed as follows. From the fact that there is a strong correlation between the twist-curl and the difference of fibre orientation angles, in order to make the twist-curl close to zero, the control target is that uF-W profile (the difference profile of fibre orientation angles) should become zero everywhere in the cross-direction of the paper.

In order to accomplish this control target, the actuators are manipulated according to the following strategies. First, in order to make the average value of uF-W profile close to zero, the edge flow valves are manipulated. Second, in order to make the R (maximum minus minimum value) of uF-W profile close to zero, the slice lip actuators and the edge flow valves are manipulated. Here, the slice lip actuators are utilized to adjust the local shape of uF-W profile and the edge flow valves are useful to improve the global shape of the profile.

From these discussions, it is obvious that both the edge flow valves and the slice

lip actuators are absolutely necessary to accomplish the control target.

Numerical model of the actuator manipulations We successfully derived the numerical model of fibre orientation angle changes when the edge flow valves and the slice lip actuators were manipulated. The model is essentially non-linear, but by differentiating it, the linearized local model is obtained as follows.

where: K: The matrix that expresses the linearized numerical model of the edge flow valves and the slice lip actuators uF-W (i) = uF (i) – uW (i) uF (i) : fibre orientation angle on the felt side at the i – th slice actuator uW (i) : fibre orientation angle on the wire side at the i – th slice actuator S(i) : Manipulated value of the i – th slice actuator ET : Manipulated value of the edge flow valve at tender side ED : Manipulated value of the edge flow valve at drive side In the expression (1), the matrix K is calculated from the slice lip shape, fibre orientation angle measurement value and other coefficients.

These numerical models correspond closely with the actual responses of fibre orientation angles as shown in Figs. 5 and 6.

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Fig. 8. The comparison of twist-curl profile between before and after automatic control.

Fig. 7. Relative velocity component in MD at the outlet of the slice lip.

Optimizing control calculations Based on the numerical model, the optimizing control algorithm of fibre orientation angle profile was constructed by utilizing the optimizing control technique as follows.

The estimation function J of the control is set as follow:

The manipulated value (dS) of the edge flow valves and the slice lip actuators to decrease this estimation function at the steepest rate is given by the steepest descent method as:

Where: ´ : some positive number (control gain)

On the other hand, the slice lip manipulations bring about interference with the basis weight profile. Therefore, the noninterference algorithm concerning basis weight profile control was added and made it possible to control both the basis weight and fibre orientation angle profiles simultaneously by the slice lip actuators and dilution valves.

CONTROL RESULTS AND BENEFITS

This control algorithm was incorporated into the software in Yokogawa’s QCS system and the on-line fibre orientation control has been executed on the paper machine since the beginning of 2007.

Immediately after the machine starts, the coarse control is executed in order to make uF-W profile (the difference profile of fibre orientation angles) flat as rapidly as possible. In fact, through 38

PULP & PAPER CANADA March/April 2010

Fig. 9. Transition of twist-curl in long run operation.

the coarse control, the convergence time of the 2-sigma of uF-W profile was reduced by 70 % compared with manual operations and it took only 30 minutes to make the 2-sigma of uF-W profile less than 1.5 degree. On the other hand, during the steady state of the production, the fine control is executed to maintain the paper quality as stable as possible. Through the fine control in a long run operation, the 2-sigma of uF-W profile was improved by 30% in average compared with manual operations.

Those improvements of uF-W profile resulted in the improvement of twist-curl as a more intrinsic paper quality. We measured the actual twist-curl profile of paper which was sampled at 23 points in cross-direction by hanging twist-curl measurement method after the fibre orientation control had been implemented and found out that the twist-curl profile was kept within the desired range, -10 to 10 mm (Fig. 8).

Moreover, Fig. 9 illustrates the transition of the average degree of twist-curl in each month from Jan. 2006 to Feb. 2008. The degree of twist-curl was defined as the average of the absolute value of DCL (twist-curl) over the entire width of the paper machine. The long run continuous control has been implemented since the beginning of Feb. 2007. The degree of twist-curl was clearly decreased by applying the automatic control. Consequently, this fibre orientation control system succeeded in reducing the degree of twist-curl and improving the quality of copy paper.

CONCLUSIONS

The on-line fibre orientation measurement and control system was developed and applied to an actual paper machine. Basically, the technology of the on-line fibre orientation measurement made it possible to realize the closed-loop control of fibre orientation. The control algorithm utilizes the optimizing control technique based on the numerical model of the fibre orientation pulpandpapercanada.com

PEER REVIEWED angle change by the edge flow valves and the slice lip actuators. The control has realized significant improvement of productivity and quality in a long-run operation since Feb. 2007.

LITERATURE

1. ASTROM, M. E., AMIRI, R., and GRAY, D.G., Chiral Twisting Curl of Paper Sheets, Nordic Pulp and Paper Research Journal No.1, p16-17,25(1994) 2. ABE, Y., TODOROKI, H., TAKEUCHI, N., and SAKAMOTO, A., Method for Measuring Fiber Orientation on Paper Surface, APPITA Journal, p. 625632(1996) 3. NONOMURA, F., ABE, Y., and TAKEUCHI, N., A Study on the Curling Behavior of Paper Resulting from Heatroller Heating, 1999 International Paper Physics Conference, San Diego, California.

4. AMIRTHALINGAM, R., Curl and Twist Modeling for Monitoring and Control, Control Systems 2002, Stockholm, Sweden.

5. HELLSTROM, A., The Two Sides of Fiber Orientation, 2005 TAPPI Practical Papermaking Conference, Milwaukee, Wisconsin.

6. FUKUOKA, K., HATANO, A., ABE, Y., and TAKEUCHI, N., Development of On-line System for Measuring Fiber Orientation on Paper Surface, 2000 TAPPI

Engineering Conference, Atlanta, Georgia.

7. ODELL, M., and PAKARINEN, P., The Compleat Fibre Orientation Control and Effects on Diverse Paper Properties, 2001 Papermakers Conference, Atlanta, Georgia.

8. SUBBARAYAN, R., TRAN, P., and CHEN, S., Control of Fiber Orientation of a Paper Sheet Using On-line Measurements, Control Systems 2002, Stockholm, Sweden.

9. KNIIVILA, J., and NUYAN, S., Focusing on the

Edges of Profile Control, Control Systems 2004, Quebec City, Canada.

10. CHEN, S., and HELLSTROM, A., Online Measurement and Control of Sheet Dimensional Stability – Twist and Curl, Control Systems 2006, Tampere, Finland.

11. YAMAMOTO, J., TODOROKI, T., ONO, K.,OCHI, T., SASAKI, T., SANO, H., New Automatic Control System for Fiber Orientation and Improvement of the Quality of Copy Paper, PaperCon ’08, Dallas, Texas

Résumé: On a élaboré un nouveau système automatique de contrôle et de mesure de l’orientation des

fibres. Ce système permet de mesurer en continu l’angle d’orientation des fibres à la surface du papier, et de manipuler automatiquement l’ensemble de vanne de réglage des bords et les actionneurs de la règle à la caisse d’arrivée, afin de réduire la différence de l’angle d’orientation des fibres entre les côtés feutre et toile. Ce contrôle est installé dans une machine à papier pour photocopie depuis le début de 2007, et le degré moyen de roulage a été réduit de moitié.

Keywords: FIBRE ORIENTATION, FIBRE ORIENTATION CONTROL, EDGE FLOW, SLICE LIP, TWIST-CURL.

Reference: SASAKI, T., SANO, H., YAMAMOTO, J. TODOROKI, H., ONO, K., OCHI, T. On-line

Fiber Orientation Measurement and Control, Pulp & Paper Canada 111(2): T32-T36 (Mar/April 2010). Paper presented at the 2008 Control Systems Pan-Pacific Conference in British Columbia, Canada, June 16-18, 2008. Not to be reproduced without permission of PAPTAC. Manuscript received Jan. 24, 2008. Revised manuscript approved for publication by the Review Panel, Nov. 9, 2009.

International Biomass Conference & Expo May 4-6, 2010 Minneapolis, MN www.biomassconference.com

TAPPI-PIMA PaperCon 2010 Conference & Trade Fair May 2-5, 2010 Atlanta, GA 800-446-943, memberconnection@ tappi.org, www.tappi.org

World Bioenergy 2010 May 25-27, 2010 Jönköping, Sweden www.elmia.se/en/WorldBioenergy/

PAPTAC Finishing, Warehousing & Shipping Annual Conference May 26-27, 2010 Quebec, Que. Jean-Marie Methot, Methot.j@ videotron.ca; www.paptac.ca

Progress in Paper Physics Seminar June 7-10, 2010 Montreal, Que. Norayr Gurnagul, 514-630-4101, ex 2241, Norayr.gurnagul@fpinnovations.ca, www.paprican.ca

PacWest Conference June 9-12, 2010 Kamloops, B.C. Mary Barnes, barnesmm@shaw.ca; www.pacwestcon.net

Zellcheming Annual General Meeting & Expo June 29-July 01, 2010 Wiesbaden, Germany zellcheming@zellcheming.de, www.zellcheming.com

China Paper Shanghai Sept. 15-17, 2010 Shanghai, China www.chinapaperexpo.com

Events

Control Systems 2010 Sept. 15-17, 2010 Stockholm, Sweden SPCI & Innventia, www.controlsystems2010.com

pulpandpapercanada.com

Send events info and news announcements to media@pulpandpapercanada.com March/April 2010

PULP & PAPER CANADA

39

T36

TECHNOLOGY NEWS

Honeywell and BTG Instruments optimize fibreline control in pulp mills Honeywell is collaborating with BTG Instruments to optimize fibreline control in pulp mills. By integrating Honeywell’s Profit Controller® suite of advanced process control applications with BTG’s line of high-performance sensors and analyzers, pulp mills can improve fiberline operations by incorporating environmental and quality aspects into their control systems. This additional information helps ensure the right amount of chemicals, energy and fibre are used throughout batch and continuous cooking, thermomechanical pulping, and bleaching processes.

“We have already seen significant interest from both existing and new customers as a result of this collaboration

because mills have struggled for many years to incorporate the right information into their control systems,” said Rick Van Fleet, global pulping APC solutions manager, Honeywell Process Solutions. “Combining Profit Controller’s optimization qualities with the visibility provided by BTG’s products will make efficient pulp mill fibreline control a reality.”

As part of the collaboration, mills can streamline maintenance and sustain system operation through Honeywell’s remote monitoring service offering, as well as through BTG’s global service network.

Honeywell International, www.honeywell.com/ps.

LC pulper upgrades save energy Despite reduced energy use, existing LC pulpers can improve the quality of the pulped stock at low consistency, up to 8% stock consistency. Voith Paper has successfully upgraded LC pulpers with IntensaTechnology around the world, in Japan, North America, Germany, and other European countries. Four more IntensaTechnology upgrades are planned for the end of 2009 in Brazil and 2010 in Thailand.

This unique concept, which has been available on the market for almost two years, consists of three main components. A specially designed IntensaDeflector improves the flow geometry for fast bale submergence and improved agitation. An optimized or new

rotor accelerates pulping. A bale breaker is also installed in the pulper.

Thanks to the energy savings of up to 30%, upgrading an LC pulper to IntensaTechnology can result in a return on investment in six months. In addition to the energy savings, customers benefit from more reliable pulper operation, higher stock consistency, a higher operating level, and increased capacity when required.

IntensaTechnology can be applied to almost any LC pulper type from a variety of manufacturers. Voith Paper offers a pre-rebuild analysis.

Voith Paper 613-632-4163, www. voithpaper.com

Domtar to enhance forest operations management with ESRI technology Domtar has signed an enterprise license agreement (ELA) to expand its usage of ESRI’s geographic information system (GIS) solutions within its Forest Products Group division to gain better operational visibility and enhance forest operations management.

The system will help Domtar manage its harvesting activity to protect forest values such as fish and wildlife, flora, water resources, tourism and natural heritage, and manage assets such as bridges, culverts, and roads. Domtar also uses GIS to support third-party

40

forest certification, regulatory reporting, and public consultation with external stakeholders for forest management planning.

“ESRI’s leading GIS technology provides [businesses] the capability to produce a comprehensive picture of their operations in real time, enabling them to make critical decisions quickly and effectively,” said James Wickson, vice-president of sales and professional services, ESRI Canada.

ESRI Canada, www.esricanada.com/ products/arcgis

PULP & PAPER CANADA March/April 2010

pulpandpapercanada.com

TECHNOLOGY NEWS

Professional Connections Equipment

VINCENT CORP. SCREW PRESS Clarifier Sludge Knots & Shives Screen Rejects Stock Thickening Recycle Rejects Black Liquor

FREE ON-SITE DEMOS www.vincentcorp.com (813) 248-2650 Fax: (813) 247-7557

Careers PulP & PaPer Jobs Freeman Staffing, Inc. specializes in the placement of engineers (all disciplines), production type supervisors, managers, mill and/or plant managers and corporate executives in the pulp & paper industry, North America-wide. For specific current job searches call us or contact our web site. All resumes are treated with complete confidentiality.

Freeman Staffing, Inc.

(800) 221-9629 or FAX (360) 653-8271 email: markp@freemanstaffing.com

web site: www.freemanstaffing.com Good things come in small packages.

To inquire about advertising in Pulp & Paper Canada contact

Jim Bussiere 800-268-7742, ext 3606 or 416-442-5600, ext 3606 Fax: 416-510-5140

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Successful start-up of the first Andritz gap former

Following the rebuild of the wet section of the PM4 paper machine at Cartiere Modesto Cardella S.p.A., Italy, Andritz announces the successful start-up of its first PrimeForm TW gap former. The gap former is combined in this instance with a PrimeFlow TW two-layer headbox with PrimeProfiler F dilution water control.

The concept Andritz has supplied provides high dewatering performance and production of corrugated base paper grades with a minimum of two-sidedness. Initial results after the startup show a significant improvement in paper formation and strength properties.

The paper machine has a design speed of 1,200 m/min and a wire width of 3,180 mm. The corrugated base paper, with a basis weight range of 90 to 170 gsm, is produced from 100% waste paper.

Andritz 514-631-7700, www.andritz.com

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Telephone 416. 391. 2322 E-mail mail@dickeng.com Web site www.dickeng.com

Global Know-how and Local Service for the Forest Industry Pöyry (Montreal) Inc. Montreal, QC 514 341 3221

Pöyry Forest Industry Consulting Inc. Tarrytown, NY Montreal, QC 914 332 4000 514 845 8715

Pöyry (Vancouver) Inc. Vancouver, BC 604 689 0344

Pöyry (Appleton) LLC Appleton, WI 920 954 2000

Engineering balanced sustainability for a complex world. www.poyry.ca

March/April 2010 PULP & PAPER CANADA

41

PHOTO FILE

Meet the next generation Grad students from across the country congregate in Montreal for annual meeting

H

ailing from UNB to UBC, graduate students gathered during EXFOR and the PAPTAC Annual Meeting to share their research with the industry. A poster session on the second day of the annual meeting gave delegates an introduction to the students’ work. It was followed by the Canadian Pulp and

Paper Graduate Student Seminar on the day after the annual meeting, Feb. 4. The student seminar is a joint event sponsored

by PAPTAC’s Research Committee and the PAPIER research network. It wraps up with cocktails and dinner, held this year at the McGill Faculty Club.

Awards

Alkis Karnis Memorial Prize Winners – 2010 (for best poster): 1. Ario Madani – University of British Columbia, Fractionation in a Viscoplastic Fluid 2. Elie Afif – University of Toronto, Supercritical Water Gasification of Solid Wastes 3. Vincent Leung – McMaster University, Streaming Potential in Microfluidic Channels of Paper Henry I. Bolker Prize Winners – 2010 (for best seminar): 1. Ario Madani – University of British Columbia, Fractionation in a Viscoplastic Fluid 2. Quan Wen – McMaster University, Designing Microgels for Advanced Paper Structure 3. Jingyun Wang – McMaster University, Influence of Paper Surface Chemistry on the Activity of Immobilized Antibodies 42

PULP & PAPER CANADA March/April 2010

Award winners (l-r) Vincent Leung, Quan Wen, Tracy (Jingyun) Wang, Elie Afif, and Ario Madani were singled out for the technical content and presentation of their posters and seminar sessions. pulpandpapercanada.com

PULP & PAPER TECHNICAL ASSOCIATION OF CANADA

COMMUNITIES –

CONNECTING PEOPLE

PAPTAC’S TECHNICAL COMMUNITIES ‐ Developing our members' networks and providing a tremendous tool to stay connected with your industry!

PAPTAC’s standing committees have always played an essential role in providing platforms and forums for members to exchange on common subjects and interests. Feedback received from participants has always been very positive in creating opportunities for the individual members to develop their network and skill set, while providing value back to their companies. These communities will play a similar role to the traditional committees while utilizing the Web and conference calls as key vehicles to promote this exchange.

WITH A BRAND NEW INITIATIVE currently being implemented providing a ListServ to each community, this exchange will be more efficient and simple than ever before and will strengthen the interaction and value derived from actively participating in these communities.

Members will be able to share concerns, interests, problems and solutions through this ListServ, a centralized e‐mail distribution list, automatically broadcasting their questions and topics of discussions to other members in that community.

We are very pleased to bring this new feature to our member benefits. Current committee members will automatically be added to their respective “Community” list. PAPTAC members who wish to join the ranks of one or several communities can visit paptac.ca and select the community of their choice. Non‐members must sign up for PAPTAC membership prior to being able to join a community. We look forward to your active participation!

For more information, call Carmie Lato at 514‐392‐6969 / clato@paptac.ca.

2010 EXFOR & Annual Meeting Preprint CD now available.

Purchase your copy, and other publications, at our on‐line bookstore:

www.paptac.org/store

Virgin fiber. Reclaimed fiber. Moral fiber.

It’s how the best paper is made. With strength of character and firmness of purpose. For 60 years, Buckman has provided just that to the paper industry. We’ve grown into a global success by aligning our business model with our customers’ specific needs. With Buckman, you get continuity, commitment, and innovation. You get professionals who see your success as a measure of their own.

Find out how we can help your mill save time, energy, and money.

Visit buckman.com or call 877-BUCKMAN.

©2009 Buckman Laboratories International, Inc.