International Filtration News / Vol. 3

The gateway to new business in North America

Reserve your space at FiltXPO™, North America’s only exhibition and technical conference dedicated exclusively to filtration and separation. Sign up to exhibit where your latest developments meet decision makers. Join global leading companies from more than 15 countries in the filtration and separation industry to connect with 1,500 industry professionals.

Network with customers and new partners in the design, manufacture, sales, and use of filtration and separation products, equipment, and services. Take advantage of on-site Filter Media Training. Don’t miss the Summit for Global Change, where five panels of industry experts take on society’s most urgent challenges. Be where our industry is going.

To book a stand, contact Joe Tessari jtessari@inda.org or +1 919 459 3729. filtxpo.com

Strategic Director Waterloo Filtration Institutue +1 866.546.0688 x 116 iyad@wfinstitute.com

Thad Ptak, Ph.D.

Principal, Ptak Consulting +1 414.514.8937 thadptak@hotmail.com

Vice President, Sales & Marketing Mazzei Injector Company +1 661.363.6500 jlauria@mazzei.net

Bob McIlvaine

President, The McIlvaine Company

+1 847.784.0013 rmcilvaine@mcilvainecompany.com

Dave

Marc McKenna

Engineer Valin Corporation www.valin.com

Technical

Matt O’Sickey

Director of Education & Technical Affairs, INDA mosickey@inda.org +1 919.459.3748

President, ETS, Inc. +1 540.265.0004 mmck@etsi-inc.com

CALL FOR CONTRIBUTORS

International Filtration News is actively seeking contributed technical articles from qualified industry professionals and those allied to the filtration industry. If you would like to pitch an article for publication in IFN, contact Caryn Smith at csmith@inda.org or +1 239.225.6137.

Caryn Smith Chief Content Officer & Publisher, INDA Media csmith@inda.org

Len LaPorta Managing Director Wiley Bros.-Aintree Capital, LLC llaporta@wileybros.com

Dr. Iyad Al-Attar

Jim Lauria

Molinari

Sales

CSMITH@INDA.ORG +1 239.225.6137

Stormy Weather Hits Home

“We forget that the water cycle and the life cycle are one.”

— Jacques Yves Cousteau

Tis issue has an underlying theme, which I will explain with you in a moment. First, two articles share a focus on best practices in managing water. “Stormwater: Ozone’s Next Frontier,” page 22, and “Rainwater Diversion Strategies,” page 26, spotlight water filtration from weather events.

Indoor air quality is discussed in “Smarter Filtration Rhetoric,” page 30.

Various measurements and testing applications are discussed in “Proven to Be Effective,” page 15, “Sensors for IAQ Applications,” page 19, and “The Quality Factor,” page 28.

As this all came together, public health and well-being kept coming to mind. In fact, my interview with Airmid CEO Dr. Bruce Mitchell (page 15) gave me food for thought. Airmid is a quality testing and verification facility for companies who want third-party validation on product claims. Yet, Mitchell –a practicing MD – has a personal interest to study air movement and its impact on the transmission of germs. He says, “We want industrial filtration end-users to be confident that their air quality solutions are tested and effective, especially when the next pandemic comes around. Eventually it will come, at some point, in our future.”

Furthermore, Dr. Iyad Al-Attar of the Waterloo Filtration Institute writes (page 30), “The best way to grant air filtration the attention it deserves is to highlight its impor-

tance to our well-being, health, and safety of human occupants and the equipment it protects, such as heating, ventilation, and air conditioning (HVAC) systems.”

They share a vision to see air quality receive deeper attention to prevent the spread of widespread illness in the future.

And, the same goes for water.

Jim Lauria of Mazzei Injector Company, says (page 22), “Many of the same microbes that present health risks in drinking water –including Giardia, Cryptosporidium, Campylobacter, Rotavirus, and Legionella – are concerns in stormwater, particularly when the water is aerosolized into particles that can be drawn into the lungs. ... Exposure to Legionella through aerosolized water is no idle worry.” In fact, he notes it can be deadly.

Ironically, one of my dear friends shared with me yesterday (and as I am write this) that her elderly father is in the hospital with Legionella, in our town of Fort Myers, FL. In September 2022, Fort Myers was devastated by Hurricane Ian. His home is on the edge of wetlands that were flooded with toxic stormwater – as is mine which is just up the road from his. With this weather event and all its environmental impact, the idea of public health and well-being from air and water quality is personally top of mind for my community. It’s a bit close to home, for me.

Caryn Smith

Chief Content Officer & Publisher, INDA Media, IFN

International Filtration News Editorial Advisory Board

R. Vijayakumar, Ph.D., Chair

AERFIL

Tel: +1 315-506-6883

Email: vijay@aerfil.com

Rahul Bharadwaj, Ph.D.

Lydall Performance Materials

Tel: +1 603-953-6318

Email: rbharadwaj@lydall.com

James J. Joseph

Joseph Marketing

Tel/Fax: +1 757-565-1549

Emai: josephmarketing120@gmail.com

Wenping Li, Ph.D.

Agriltech Research Company

Tel: +1 337-421-6345

Email: wenpingl@agrilectric.com

Ernest Mayer, Ph.D.

E. Mayer Filtration Consulting, LLC

Tel: +1 302-981-8060

Email: ernestmayer6@gmail.com

Robert W. McIlvaine

The McIlvaine Company

Tel: +1 847-784-0013

Email: rmcilvaine@mcilvainecompany.com

Thad Ptak, Ph.D.

TJ Ptak & Associates

Tel: +1 414-514-8937

Email: thadptak@hotmail.com

International Filtration News is published by INDA Media, the B2B publishing arm of INDA, Association of the Nonwoven Fabrics Industry. +1 919.459.3700 info@filtnews.com | www.filtnews.com News & Press Releases to IFNNews@inda.media

INTERNATIONAL FILTRATION NEWS (ISSN: 1078-4136x), is published bi-monthly by INDA, Association of the Nonwoven Fabrics Industry, +1 919.459.3700. Subscription price is $125 per year for non-U.S. subscribers. Periodicals postage paid at Novi, MI, and additional mailing offices. POSTMASTER: Please send address changes to International Filtration News, PO Box 158 Cedar Rapids IA 52406-0158 USA.

MISSION

International Filtration News covers the topics and technologies that will shape the future of filtration and separation. Using subject matter experts from all parts of the industry, IFN is the leading source for the dialogues, debates and innovations across the full spectrum of filtration and separation applications and processes.

If you would like to utilize your expertise to help shape the content in the IFN , consider applying for the IFN Editorial Advisory Board. We welcome participation through input on trends and innovations, new story ideas and overall thought leadership. This is a collaborative board that meets quarterly to discuss the state of the industry. Send an email to Caryn Smith at csmith@inda.org for consideration.

GEA Cuts Water and Power Consumption in Half for CIP in Membrane Filtration

German systems supplier GEA, one of the world’s largest suppliers of systems and components to the food, beverage, and pharmaceutical industries, can reduce water and power consumption during the cleaning of membrane filtration plants by up to 50 percent with two new digital tools. The software duo, GEA Smart Filtration CIP and GEA Smart Filtration Flush, automatically intervene in cleaning-in-place (CIP) processes, pulsing the pumps and flushing the membranes individually and according to real-time water quality.

Up to 50 Percent Less Water

Membrane filtration plants separate or concentrate substances without thermal stress. Membrane filtration is primarily used in food manufacturing – including new foods – and in dairy processing. Common product examples include dairy protein and fish collagen isolates. Until now, cleaning this equipment was energyand water-intensive, requiring three or four individual cleaning steps with different chemical cleaning agents to be pumped and circulated throughout the equipment for a specified amount of time before rinsing it out with water.

In contrast, GEA Smart Filtration Flush uses sensors to constantly measure the permeate

quality of the water during the flushing process, reducing the freshwater required. Setting blanket rinsing intervals and water quantities in advance is no longer needed as the software stops the process as soon as the necessary hygiene level is reached, and the cleaning agents are discharged. Depending on the type and size of the plant and the water properties, operators can reduce their freshwater requirements by up to 50 percent.

Water-Saving CIP Optimization

“A typical dairy whey protein concentration process needs two to four filtration plants connected in a series. This set up can require more than 100,000 liters of water per cleaning cycle,” explains Nils Mørk, R&D Engineer for membrane filtration at GEA. “Today, we know from plant tests that we can save well up to 50,000 liters of water per cleaning in such large plants and 500 to 700 liters per CIP in small productions.”

Also, when less water is fed into the process, this decreases the amount of wastewater which needs to be discharged. “Many manufacturers can only clean their filtration systems successively because the peak flows during flushing of filtration plants often exceed pipeline capacity. That can create a potential

t With two new digital tools GEA Smart Filtration CIP and GEA Smart Filtration Flush, GEA reduces water and electricity consumption by up to 50 percent when cleaning membrane filtration plants, such as this dairy plant.

GEA

safety hazard for staff and cause contamination in the production area. Smart Flush eliminates this peak water flow problem because we can significantly reduce pressure fluctuations in the water supply and reduce the overflow of drain lines,” says Mork.

Up to 50 Percent Less Energy

The second software module, GEA Smart Filtration CIP, regulates cleaning efficiency, by causing pumps to operate in a pulsating manner as opposed to running continuously. As a result, the CIP process pumps consume up to 50 percent less energy. Traditionally, the best results were achieved by cleaning with high shear forces (e.g., mechanical washing with a strong rinse flow).

The Washing Machine Principle

Tests conducted by GEA on various membrane plants prove that the same level of hygienic cleaning is achieved even if the pump only operates at short intervals – providing the time, temperature and chemical concentration is kept constant. “Our method, now applied to membrane plants, mirrors the basic principles used successfully by washing machines: agitate the clothes followed by intervals of rest, allowing the cleaning agent do its job,” explains Mørk. Compared to plants with standard pump operation at full load, small production plants with GEA Smart Filtration CIP would save between 5 and 7 kilowatt hours per cleaning. Large filtration plants would require 60 to 100 kilowatt hours less electrical energy per CIP process thanks to this innovation. www.gea.com

 For details on how to submit your company’s technology for consideration as a “Technology Spotlight” in IFN , contact Ken Norberg at ken@filtnews.com or +1 202.681.2022.

NOTES TECH

Donaldson Company, Inc., a leading worldwide manufacturer of innovative filtration solutions has released Alpha-Web ® filtration media. This new hydraulic filtration technology significantly improves hydraulic fluid cleanliness which can extend hydraulic component life, decrease downtime and lower the cost of equipment ownership.

Filters must stand up to the challenge of maintaining fluid cleanliness and system protection against frequently changing flow rates prevalent in real-world operating conditions. AlphaWeb filtration technology features a first-of-its-kind fine-fiber layer to trap and lock particles during frequent flow-rate changes, delivering transformational improvement in hydraulic equipment protection. Advanced contaminant retention results in cleaner oil and helps ensure that equipment will continue to perform better, and longer, with a lower risk of wear, damage and unplanned downtime. www.donaldson.com

In response to growing demand for flexibility in process water treatment, Marmon Industrial Water recently launched the Graver mPowdex ® Condensate Polishing Trailers. As the first precoat filter demineralizer on wheels, the mPowdex® system will allow plants to reuse and recover steam condensate on an as-needed basis, providing water, energy and capital savings across manufacturing sectors, including power generation, refining and petrochemical applications.

“The Graver name has been synonymous with condensate polishing for over half a century,” said John Yen, Director of Strategic Marketing & Innovation at Marmon Industrial Water. “Now more than ever, plant managers and operators are in critical need of efficient water treatment technologies that can be deployed quickly, due in part to new environmental regulations, aging infrastructure, and capacity increases. Graver mPowdex® is the solution and we are thrilled to continue sharing our expertise with the sector.”

mPowdex ® is a precoat filter demineralizer that combines ion exchange and filtration to remove solid and dissolved particulates, such as iron and copper, from high-value process steam. By removing these contaminants, it protects costly generation assets, such as turbines and deaerators, and maximizes plant uptime. This form of condensate polishing has also been shown to drastically reduce the frequency of required blowdowns, where large amounts of water, energy and labor are lost. www.graver.com

LG Chem announced that the company has shipped more than 10,000 RO membranes to the Guoan lithium extraction project led by CITIC Group, China’s largest state-owned investment company. The Guoan project, which kickstarted its full-scale operation in Qinghai province this year, is the largest salt lake lithium extraction project in China.

TUS-Qingyuan which manages the lithium extraction project across engineering, procurement, and construction (EPC), expects to produce 20,000 tons of lithium carbonate annually by using LG Chem’s RO membranes. This is equivalent to manufacturing batteries for nearly half a million EVs. In addition, this is the world’s largest lithium extraction project using a filtration device.

RO membranes significantly reduce the amount of energy required for lithium production. To obtain lithium dissolved in salt lakes, water must be evaporated to increase its concentration which had been per-

formed by applying heat to remove water. With the reverse osmosis process using RO membranes, however, it allows quick filtering out the water molecules without applying heat.

Five out of nine salt lake lithium extraction projects in China adopted the RO membrane method. As a result, the RO membrane market in China expects to grow by more than 8% each year. www.lgchem.com

Marmon Industrial Water Launches Graver Mobile Powdex Condensate Polishing Trailers

LG Chem Supplies RO Membranes to China’s Largest Salt Lake Lithium Extraction Project

Donaldson’s Alpha-Web® Media Provides Cleaner Hydraulic Fluid

p LG Chem RO membranes.

Particulate captured in Alpha-Web fine fibers.

NOTES TECH

Ahlstrom Launches Renewable Lignin-Based Automotive Filter Media

Ahlstrom is introducing a new range of renewable and sustainable filtration solutions for automotive applications. Ahlstrom ECO™ is a technology supporting the increasing sustainability demands of the global transportation market and offering a new choice for filter manufacturers.

Developed by Ahlstrom, a new renewable and sustainable filter media utilizes lignin-based* impregnation, replacing fossil-based resin. The resin solution contains a significant amount of bio-based, renewable lignin, while the mechanical properties and the durability of the filter media, even in challenging environments, are maintained.

According to Ahlstrom’s initial estimates, the new lignin-based impregnated filter media displays a lower carbon footprint than a standard fossil-based resin media. Additionally, the lignin-based impregnation recipe brings a significant reduction, between 50-70%, of formaldehyde emissions during the curing process.

Ahlstrom is partnering with Tecfil, a leading automotive filter manufacturer in Latin America, who is incorporating Ahlstrom ECO™ solution into a final filter design. www.ahlstrom.com

VEOCEL™ Upgrades Lyocell Shortcut Fiber Offering

Lenzing Group, a leading global producer of wood-based specialty fibers, has launched upgraded lyocell shortcut fibers by VEOCEL™ for the flushable market. The upgraded lyocell shortcut fibers not only have high dispersibility, which make them ideal for use in flushable wipes, they also have an upgraded finish, an added benefit for wipes manufacturers. The upgraded finish enhances efficiency of the wipe production process, improves the processability of fibers and helps to create higher quality products. The fibers are also offered as carbon neutral, thus contributing to a global push to reduce the industry’s carbon footprint.

The new finish of the upgraded lyocell shortcut fibers offers protection against mechanical stress at commonly used water temperatures such as 0°C to 40°C during the wetlaid production process. This helps to avoid the creation of fiber lumps during the opening and dilution of fibers in preparation tanks. The finished product will also have enhanced physical quality and appearance thanks to the upgraded finish which improves web formation during the process.

The new and improved carbon neutral lyocell shortcut fibers by VEOCEL™ can be purchased from Lenzing’s production site in Mobile, Alabama. www.lenzing.com

CLEANR Debuts Rapid Prototyping of Its Microplastic-Filtering Technology for Washing Machine

CLEANR, a market-disruptive microplasticfiltration technology company, has accelerated the development of its solutions for washing machine manufacturers through its early access to the Formlabs Automation Ecosystem. The new platform enables new levels of 3D printing productivity through a highly scalable and automated workflow that can produce back-to-back 3D prints 24/7 with minimal human intervention.

The 3D printing platform will enable CLEANR to accelerate the introduction of its new microplastic-filtering solutions and collaborate quickly and efficiently with appliance manufacturers to integrate the tech-

nology into their washing machine designs. Washing machine wastewater is the world’s largest source of microplastic pollution and has come under growing regulation in Europe and North America. Multiple governments are developing and enacting legislative requirements to mandate manufacturers to outfit new household washing machines with microplastic-filtering devices to prevent the flow of harmful microplastics into waterways, ecosystems and food chains.

Beginning in January 2025, France will require all new washing machines sold incountry to include a microplastic-filtration solution. Meanwhile, members of the UK par-

 The CLEANR internal washing machine filtration product utilizes its small form factor and elegant design to fit easily inside existing washing machines. CLEANR’s patent-pending filtration technology allows for existing washing machine systems to push water though our market leading solution while simultaneously removing more than 80% of microplastics measured down to 50-microns.

liament, California and Oregon state legislators in the U.S., and provincial legislators in Ottawa, Canada are working through similar proposals. www.cleanr.life

DuPont Launches Next Generation of PES In-Out Ultrafiltration (UF) Membranes

DuPont announced the commercial launch of the next generation of multi-capillary PES In-Out Ultrafiltration (UF) membranes – DuPont ™ Multibore ™ PRO. Customers can leverage Multibore ™ PRO to reduce the number of modules needed in water purification systems – as part of multi-technology approaches to desalination, municipal drinking water, or industrial water applications.

The first polymeric membrane with a completely new geometry since the seven-capillary Multibore™ debuted over two decades ago, DuPont™ Multibore™ PRO combines 19 bores within a single fiber to enable customers to realize both performance and sustainability benefits through the increased surface area and reduced installation area for a given flow rate target.

DuPont ™ Multibore ™ PRO is the newest innovation within the recently launched DuPont™ IntegraTec™ UF portfolio, one of the most versatile ultrafiltration technology offerings in the industry. Integrating technologies from three legacy brands, DuPont™ IntegraTec™ offers an extensive range of reliable and durable modules and rack configurations, capable of solving a wide variety of water treatment challenges by harnessing precision membrane chemistry.

With more than double the capillaries, this increased membrane filtration surface area per module means fewer modules are required in

water treatment installations to achieve higher productivity and efficiencies, driving value for operational expenses. UF modules equipped with Multibore ™ PRO membranes can achieve floor footprint savings of up to 15 percent per rack, while also reducing both capital expenditures due to reduced rack components and assembly costs.

www.dupont.com

Boosting Efficiency and Quality with ELSNER’s Automated Filtration Manufacturing Machinery

Efficiency is crucial in the manufacturing industry, where time is money. For success, it is essential to produce products quickly and efficiently; this is where automation plays a vital role. Investing in ELSNER’s automated filtration manufacturing machinery can save valuable time and resources, increase productivity, and consistently manufacture superior products. ELSNER’s machines are trusted by numerous industries worldwide, with over 3000 machines operating across 60 countries. Since the early 2000s, ELSNER has been providing solutions to the filtration industry, earning a reputation as a leader in the field. ELSNER’s experience and expertise can help you overcome your most significant challenges and meet the demands of your customers.

Increase Productivity and Quality:

It is important to recognize that automation can significantly reduce human error, leading to increased quality, precision, and accuracy within your company. Automated processes can efficiently handle repetitive tasks, ensuring greater uniformity and conformity while allowing employees to focus on more stimulating tasks, increasing company morale. Automated processes are generally more efficient than manual operations, resulting in increased productivity, decreased unit costs, and higher throughput. Our utilization of robotics to apply glue patterns reduces operator fatigue. Taking the arduous task of bead placement out of the operator’s hand frees them to focus on higher-quality tasks and prevents burnout.

Saving Time and Resources:

Manufacturers have struggled with labor pressures for decades, but the COVID-19 pandemic further highlighted the labor shortage issue. Automation presents a solution that allows companies to operate with a smaller staff while enabling employees to utilize their skills more effectively. By automating tasks such as membrane folding, outerwrap tape application, and glue bead placement, employees can focus on more advanced tasks that require a higher skill set. This improves productivity and creates opportunities for upskilling and career advancement within the organization.

A Look at ELSNER Filtration’s Solutions:

ELSNER filtration automated machinery includes:

• Automatic Membrane Folding: The EMF-42 automatically converts membrane and plastic mesh into folded “leaves.”

• Filter Assembly and Rolling: The APB42 provides automatic pack building for filter components.

• Filter Rolling and Gluing: the SFR-42 automates tasks such as glue delivery and outer wrap tape for spiral wound membrane filers.

• Filter Element Finishing: the Element Trim Saw is designed to finish the edges of industrial liquid filtration elements.

Want to learn more about how ELSNER automation can help you? Contact us at eew@elsnereng.com.

Leading Industry Experts to Give Keynote Presentations on Sustainable Textile Innovation

The stage is set for ITMA 2023 to host a highly anticipated showcase of textile technologies to be held in Milan from June 8 to 14. Exhibition space grossing 200,000 square meters of the Fiera Milano Rho exhibition center was fully booked as early as February.

The upcoming exhibition will feature over 1,600 exhibitors from 44 countries. There is a total of 20 product sectors covering the entire textile and garment manufacturing value chain, including textile composites.

Ernesto Maurer, President of CEMATEX, said: “Sustainability is no longer just a buzzword; the industry has to move faster to adopt the sustainability agenda to secure the future of their business. During the pandemic, many of our members channeled their resources into R&D activities. ITMA 2023 is perfectly timed to offer our exhibitors an opportunity to showcase these new products and cutting-edge technology.”

ITMA Industry Forums

Two industry forums will be reprised at ITMA 2023. The ITMA Nonwovens Forum and ITMA Textile Colourants and Chemicals Forum will feature renowned experts who will offer insights into current challenges and share ideas on how the textile industry can achieve sustainability by leveraging innovative technologies.

“Challenges in the industrial environment also bring with them a wealth of opportunities," says Maurer. "The ITMA forums will bring together stakeholders

across the entire value chain to review the issues of the day, dialogue, collaborate and ensure that we will have a sustainable future. ITMA 2023 offers a unique platform as it attracts all the textile industry players in one convenient place.”

Nonwovens Forum

The Nonwovens Forum, held on June 10, will feature a keynote presentation by Dr. Bryan Haynes, Technical Director for Global Nonwovens at Kimberly-Clark Corporation (United Kingdom). He will speak on the topic: Ready Now Nonwoven Solutions for the Global Plastics Crisis. His presentation will provide insights into solutions that are commercially available, highlighting Kimberly-Clark’s sustainability journey.

According to Dr. Haynes, who has a PhD in Mechanical Engineering from The University of Tennessee at Knoxville, the Single Use Plastics Directive was a wakeup call to the nonwoven industry. Hence,

he would like to urge industry players to explore ‘Coopetition’ or cooperative competition as this will accelerate speed to market solutions.

Following the keynote, there will be two sessions with presentations by ITMA 2023 exhibitors. The forum will end with a panel discussion on the theme, Leveraging Sustainable Innovation and Digital Technology in the Nonwoven Industry.

The panel includes Dr. Haynes and programme committee members: Dr. Behnam Pourdeyhimi, Executive Director & Associate Dean of The Nonwovens Institute; Dr.-Ing. Martin Dauner, Head of Competence Centre, Chemicals Fibres & Nonwovens of the Deutsche Institute für Textil (DITF); and Professor Stephen J. Russell, Professor of Textile Materials & Technology of Leeds Institute of Textiles and Colour.

Textile Colourants & Chemicals Forum

Held since 2011, the Textile Colourants and Chemicals Forum, to be held on June 9, will feature a joint keynote presentation by Mr. Prasad Pant, Director, South Asia, ZDHC Foundation and Ms. Sophie Mather, Co-Founder and Executive Director, The Microfibre Consortium (TMC).

The presentation, Textile Wastewater: Addressing Microfibre Loss during Manufacture, focuses on the impact of fiber shedding from clothing during manufacture and consumer use. Microfibers have been flagged as an environmental hazard and the presenters will share the key findings from the joint project by the two organizations on fiber fragmentation in wastewater. Separate forum registration and fee can be found at www.itma.com.

Participants can also attend other complimentary activities, such as the Innovator Xchange (June 9 – 13) and the Innovation Video Showcase which will feature selected videos from exhibitors. For all enquiries, please email info@itma.co. www.itma.com/events

p ITMA 2023 exhibition space grossing 200,000 square meters of the Fiera Milano Rho exhibition center was fully booked as early as February.

t There will be four featured topics at the Innovator Xchange forum, covering automation and digital future, advanced materials, sustainability and innovation. Photos courtesy of ITMA

Seizing Opportunities for Change

World of Wipes® Focuses on Turning Innovation into Action

The best and brightest of the wipes niche are invited to join at the World of Wipes ® International Conference (WOW), in Atlanta, July 17-20, 2023. When looking for sustainability solutions for filtration and textiles, there is much to learn from producers of wipes, still in high consumer demand and still in the hotseat of sustainability. The event presented by INDA, Association of the Nonwoven Fabrics Industry, spotlights current insights and future trends driving this surging $11 billion industry forward. It attracts more than 400 professionals and a host of tabletop exhibiting companies.

“I’m very excited to see the program evolve to meet the changing dynamics of the industry,” says WOW Committee Chair Jonathan M. Layer, Director of Commercial Business Development and Marketing, Fibertex Nonwovens. “I’m especially confident that adding new sessions, such as the CEO Panel and Energy Inputs, will provide unique added value and perspective.”

Transformative Thinking

This year, new to WOW are pre-conference webinars, providing a new place to connect, converse and to gain content. Details can be found at www.worldofwipes. org/preconference-webinars.html.

Another new aspect are the WOW LIGHTNING TALKS – “supersized elevator speeches” from industry suppliers. This is an opportunity for exhibitors to present their latest innovations just ahead of the popular networking reception.

WOW’s featured WIPES ACADEMY provides an educational deep dive into operational excellence, presented by Instructor Heidi Beatty, CEO, and Paul Davies, Ph.D., Senior Consultant, Crown Abbey, LLC. It is directed at raw material and packaging suppliers, brand and private label wipe converters, retail buyers, research and development professionals, marketing and product managers, and rising entrepreneurs.

Shining a light on excellence in innovation, the World of Wipes Innovation Award® recognizes companies from within the value chain that utilize nonwoven fabric/technology in a way that expands the usage of nonwovens, in categories such as raw materials, roll goods, converting, packaging, active ingredients, binders, additives and end-use products.

Market intelligence is what brings most to WOW. Over 30 speakers are expected to share their expertise and insight over the two and a half days of the main event. Attendees are encouraged to lean in and learn from their peers who are moving the needle towards a sustainable future and supporting cross-industry collaboration.

Sustaining Programming

The new CEO Panel promises a look at priorities and predictions, moderated by Chris Astley, Consultant. Discussion topics will touch on inflationary impacts, surging wages, re-shoring, as well as domestic and international drivers to supply/ demand balance. The panelists are Steve Gallo, CEO, Diamond Wipes; Markus Müller, Sales Director, Reifenhäuser Reicofil GmbH & Co. KG; R.J. Rudolph, Group

Director - CMS-RT, Rockline Industries; Jodi Russell, Vice President R&D, Cleaning Innovation, Packaging & Sustainability, The Clorox Company; and, Robert Weilminster, EVP & General Manager, US & Canada – Health, Hygiene, and Specialties Division, Berry Global.

A series of power-sessions weave together one urgent industry issue – “Plastic Policy: Closing the ‘Intentional’ Gap.” Moderated by Olivia Reiber, Key Accounts Manager, Wipes & Specialties, Berry Global, she leads the analytical presentations from Matt Seaholm, CEO, Plastics Industry Association, Murat Dogru, General Manager, EDANA, and a representative from Kimberly-Clark Corp.

“The Nonwoven Wipes Supply Chain Response to ‘Plastics Free’” with presenter Phil Mango, President, Philip Mango Consulting, considers the European Union’s Single Use Plastics Directive and its explicit inclusion of disposable wipes in 2019, which calls for an accelerated response from the industry.

Rounding out the first day are three discussions on sustainability manufacturing practices, reducing CO2 footprint while targeting CO2 neutrality by 2035 and utilizing technologies for sustainable products.

Consumer-centric talks start day two, with a “Give the People What They Want!” theme. Moderated by Jonathan Layer, Director of Commercial Business Development and Marketing, Fibertex Nonwovens, presenters include Suzanne Shelton, President & CEO, Shelton Group; Sam Nebel, Co-Founder, Goodwipes; and Paul Salama, Ph.D., CTO & Head of Innovation, Sharon Laboratories.

The final half-day on day three explores the flushability factor with five industry experts presenting aspects of the issue from fiber innovation, legislative issues, and standards development.

www.worldofwipes.org

Proven TO BE Effective

By Caryn Smith, Chief Content Officer and Publisher, IFN

With the 2020 pandemic came heightened concern for clean air and surfaces, as well as an increased use of personal anti-viral and anti-bacterial solutions. According to recent reports, 928 billion face masks totaling $389 billion in sales were sold during the pandemic. Market data provider Statista estimated that global sales of face masks, including surgical, respirators (N95-like) and cloth masks, surged from 12.5 billion in 2019 (mainly for medical personnel) to 378.9 billion in 2020 alone. Hand sanitizer sales also jumped 600% according to the Wall Street Journal – and while it settled down to more normal numbers, this category remains strong and increasing. Furthermore, according to manufacturing companies, the demand for disinfectant products spiked more than 500%. The global wipes marketplace skyrocketed and is estimated to increase 8.2% by 2027.

All in all, personal protective equipment, surface wipes, air purifying sprays were the consumer’s first line of

CEO

defense to battle the rogue virus. Products vowed to be effective, such as “kills 99.9% of germs,” whether “proven to be effective” or not. While the “shelter-

in-place” setting was controllable, air quality in public places was – and still is – subject to air filtration that is controlled by others. From transportation to schools to places of business, the public relies on air filtration systems to be as effective as possible.

This air movement is a concern to the team at Airmid Healthgroup, a testing, inspection and certification company specializing in aerobiology – the study of airborne microorganisms, pollen, spores, and seeds, especially as agents of infection. Airmid founder and CEO Dr. Bruce Mitchell uses his medical background to advise on results for their clients. They provide verifiable scientific evidence on the effectiveness of products, services, equipment, and media. Furthermore, the company uses their test environments to understand the correlation between air movement and impacts on public health.

International Filtration News spoke to Dr. Mitchell on his mission to study air quality, and Airmid’s dedication to quality testing and certification solutions.

Airmid Healthgroup is on a mission to take testing to the next level by validating consumer product expectations and understanding more about air quality post-COVID.

p 3-Cubic Meter Test Chamber Airmid

International Filtration News: What is your background and how did Airmid Healthgroup begin?

Dr. Bruce Mitchell, Airmid CEO: I was a practicing medical doctor and a clinician for the great majority of my life. My medical background has taken me through the United Kingdom, the United States and Canada, as well as Ireland. Among other experience, in the U.S., I was based in Connecticut, where I was a fellow in Yale University and in Canada, I was at a McMaster University. Currently, I am a fellow of the Royal College of Physicians in Ireland, the Royal College of Physicians in Canada and a diplomat of the American Board of Allergy and Immunology. I also serve as director of the Immunology Laboratory, Blackrock Clinic and a past President of the Allergy Foundation of Ireland, and a past member of the WHO sponsored International Workshop on Dust Mite Allergy.

So, you could say that I am heavy on the academic side of medicine. In particular, I worked under Tom Platts-Mills [currently a Professor, Medicine at University of Virginia specializing in Asthma, Allergy and Immunology]. He and I worked closely for many years doing research involving environmental controls. Ultimately, we each went on to different opportunities.

Much of the environmental research on which he and I focused was related to asthma and allergy – what in our environments make people become asthmatic. It was always clear to me that there was a need for measurement. The information on common exposures and dose responses was not based in science.

I had in my mind early on to develop a laboratory facility that could fill this gap in research, and it took me quite some time to get here. I made several attempts early on, but I was too busy, clinically. Then in 2008, an opportunity came and this time I took it to start Airmid. The result has been very successful, and we are helping our international client base to verify their product claims.

IFN: Tell us about your facilities and capabilities.

Mitchell: While we are based in Dublin, Ireland, the largest portion of our client base comes from corporate brands in the U.S. We’ve even gone as far as Hong Kong to do a study for a client. We also work with government authorities in Ireland on mold remediation in old buildings.

At the onset of COVID-19, we had an array of testing capabilities to offer and were overwhelmed with client work to verify claims. We leveraged our viral capabilities which we had developed prior to the pandemic, as well as utilized our established microbiology lab and allergy lab. A unique element of our services became quite beneficial to our client services – which is our suite of nine test chambers of varying sizes.

Essentially, these chambers are a variant of clean room technology, built by engineers who have this expertise, and are completely controlled to avoid any contamination. As full-size rooms, we can mimic a variety of environmental conditions, safely introduce and contain microorganisms, evaluate how they behave

when in contact with a client solution, and then decontaminate the chambers quickly, without harm. We can create relevant climate conditions, like specific temperature, humidity, air change rate, and air flow rate. It only takes seconds to dump all the air out of a test chamber to clear it.

In the main laboratory, we perform our analytical work with bacteria, mold, and viruses. We can take samples to see what occurs in a certain situations we have had fascinating experiences with allergens, microorganisms, and mold, which has been particularly interesting for us.

For example, we can evaluate filters which support mold growth, such as paper media, does the mold stay on the filter or does to go into the interstices of the HVAC system, contaminating the ducting? We can determine the quality of the air that's coming out of the duct. This data becomes highly relevant and highly important for companies and end users to know.

IFN : Is testing of claims and verification becoming more commonplace?

Mitchell: During COVID-19, we were at capacity with testing. It was so busy. But in general, testing can be seen as cost prohibitive, and some may not want to test unless mandated. We want companies to voluntarily test their claims, not be mandated.

Recently in the UK, an infant tragically died while living with her family in a damp apartment where toxic mold was growing.

t 28.5-Cubic Meter Test Chamber Exterior and Interior (above). Airmid

This is not a unique case, and it is happening in a first world country in 2023. Wherever the responsibility lies, we need to look out for our fellow human beings. In my opinion, you’ve got to know how products, equipment, and filter media function and how contaminants spread.

We work with many kinds of companies and manufacturers – like makers of mattresses, air and surface cleaning products, vacuum cleaners, dehumidifiers, and others. They ask us to verify their unique product claim as to its performance. Where viruses are concerned, if you are going to say “kills 99% of all germs,” data is important.

IFN: What happens when testing for a client does not meet their expectations?

Mitchell: About 20% of our client’s tests do not meet their desired measurements. However, we provide consultancy to our clients, with actionable ideas and thoughts. Honestly, companies hate when their products do not work as expected. Yet, most companies who seek our thirdparty verification are confident they will receive the results they claim because of their internal testing.

IFN: Tell us about your team and mission.

Mitchell: Our mission is to prevent ill health caused by exposure to indoor air pollutants. To achieve this goal we have assembled a unique physician led multidisciplinary team of 20-25 scientists specializing in virology, bacteriology, mycology and allergy.

Very few of the team are nonscientific. Many are trained in varying degrees and disciplines in microbiology, with specialties in bacteria or fungal molds or in testing systems. Even Airmid’s Head of Operations, Jake Behan, is a trained m icro-biologist.

IFN: Explain your testing methodology.

Mitchell: Our work primarily is chamber work. For instance, one project involved recreating a public washroom in an office setting, where we evaluated the facilities.

We tracked movement of people and various functions of the space to discover the points of contamination.

If you’ve got the flu or coronavirus as the contaminant, and your solution is applied, that is one thing. But my mind wants to know, once the application is in use, then what is a person subsequently contributing to contamination when sitting or moving through these treated spaces? What other surfaces are affected?

This is very interesting to me. The fact is that you disturb the air as you merely move through a space. How do you cause contamination of the air when you turn on the hand dryer? Well, it all depends how it’s designed. So then, should we use paper towels? In both cases, you’re essentially pushing water vapor into the air. If the water vapor is carrying something into the air, what are the ramifications?

Then, consider the floor as contaminated, as an example. Will a vacuum cleaner or filter become a source of contamination to other areas? And so on.

IFN: What’s in store for Airmid’s future?

Mitchell: We grew during the pandemic at a massive rate; we couldn’t really sustain it. Therefore, we had to prioritize and focused on air purification. We must have tested hundreds of air cleaners, with all sorts of technologies – from filtration to plasma to ionization to composites. Currently, business growth is tied to upgrading our accreditations. We have ISO 17025 accreditation, and we are qualifying for GLP (Good Laboratory Practices). Our next area of focus is to providing testing services to the MedTech and Pharma industry.

IFN: How do you support the textile and filtration industry with testing?

Mitchell: We work with manufacturers of textiles, such as evaluating extremely fine fibers to provide the potency of the microfiber in a particular direction, like anti-allergen, anti-viral or anti-bacterial. We can similarly determine results for odor reduction. The textile can be a garment to cleaning cloth. You’ll see some products that have anti-microbial additives incorporated in them and that there is a sanitation element, particularly in the bedding sector.

One active interest stemming from our work during COVID is the importance of effective filtration technologies in transportation, and we are currently working with companies on this within Europe. The goal is to prevent infection from spreading within public transportation. We want to mitigate situations and seek out environmentally-friendly approaches to balance energy efficiency and effective filtration technologies that can do the same job as, say, a HEPA filter.

To remove 99% of airborne molecules requires quite a lot of energy to produce effective results to create that airflow across the filter. There are many novel technologies that are being introduced that may or may not be effective. We are working to develop methods to accurately assess how well these technologies perform.

A product may work well on a bench test, but when scaling to the size of an actual environment in our test chamber, when simulating an airplane or train carriage, air flow patterns behave very differently. Therefore, product efficacy is also very different.

p Environmental Test Chambers Air Handling Systems. Airmid

IFN: Tell us about your work in large-scale filtration testing.

Mitchell: We can link our chambers to simulate a home environment. We can evaluate what happens in one space as a consequence of what is happening in another space. That’s highly relevant to heating ventilation and air conditioning systems. It’s fascinating how you can model the contamination pattern and sequence that occurs. We have recirculation capabilities, either by extending ducting around the outside of the chambers or within the chamber, which illustrates the flexibility of our testing systems.

We have been working to accurately represent public transportation vehicles to effectively assess whether certain technologies are beneficial. I think it's very important going forward to offer this type of full-scale testing to support companies that are addressing this question. We want industrial filtration end-users to be

confident that their air quality solutions are tested and effective, especially when the next pandemic comes around. Eventually it will come, at some point, in our future.

We are expanding our facilities, which will include two buildings totaling 10,000 sq. ft. We’ve earmarked one for a larger test chamber to simulate transportation environments, such as an airplane, subway car or bus.

We can control the hygiene of a surface with products and sprays, but with air, there is no real control other than what is used for filtration. There are regulations on water quality, but none on air quality. As we learn, we can better assist with the development side of new products, such as prototype testing.

IFN: What is the general future of testing?

Mitchell: There are large companies behind filtration, in the U.S. and internationally. It is not a fast-moving industry. I’d like to

see it evolve a little bit more. I think we’re ready for a jump to the next level. I believe it is on the radar, but because you’re dealing with large-scale mass-manufactured air systems, it’s not something that you can really change on a dime. Industry has work together on systems and media.

In textiles, there are still things to learn. How long does the effect of a product last? It is one thing to know the saturation level, but another is its continued effectiveness.

Another practical test is contact time. In testing, air is circulating at a controlled rate, yet in a real situation, air moves more unpredictably. Is the tested item getting the correct contact time for the solution and does it perform well? Is the technology wrong or possibly is it the design?

We’re on a mission to look at these deeper, challenging questions that affect the health and well-being of consumers, and help clients bring advanced solutions to end-users that meet and exceed expectations.

We offer the following services to our customers:-

MINI-PLEAT-GLASS

Mini-Pleat: H.E.P.A., ULPA & ASHRAE

Pleat heights 1/2” to 12” upto 39” wide. Interrupted beads, many configurations.

MINI-PLEAT-SYNTHETIC

Mini-Pleat: H.E.P.A. & ASHRAE

Pleat heights 3/4” to 4” upto 25” wide. Interrupted beads, many configurations.

We can incorporate the following features in your elements:

Edge Seal - allowing economical frame sealing

Slitting/Perforating - multiple packs

“W” pleat

Fire retardant glue

With our extensive knowledge in production of the innovative SOLTECH “Mini Pleat” Systems, and over 20 years of contract pleating with our revolutionary glue bead technology.

Sensors IAQ Applications

By T.J. Ptak

Numerous scientific studies have shown that air inside commercial and residential buildings is contaminated by a mixture of hundreds of gaseous pollutants and particulate matter. These contaminants may be present in concentrations sufficient to adversely affect the health of inhabitants. In addition to potentially high concentrations of indoor pollutants, the indoor exposures are significant and may vary from approximately eight hours/day to 16-24 hours/day for commercial buildings and residences, respectively.

Indoor quality problems associated with residential homes differ from nonindustrial, commercial buildings. Commercial and institutional buildings are generally equipped with automatically controlled ventilation systems, which can reduce contaminant concentration by diluting indoor air with less contaminated outdoor air. In residential buildings, the air exchange occurs by natural ventilation (open windows and doors) and by infiltration. Only a small percentage of U.S. households are equipped with the energy recovery system (fresh air systems) which provide a continuous supply of fresh air.

Ventilation together with air filtration are important methods for reducing concentration of airborne contaminants. Higher ventilation rates can improve the indoor air quality; however, the amount of energy needed to condition the indoor air in cold and hot/humid environments could be significant. On the other hand, under-ventilation may have a negative impact on the quality of indoor air, but at lower energy cost. To avoid over-ventilation (wasted energy) as well as under-ventilation (potential for poor air quality), a cost-effective ventilation control strategy is needed, such as demand-controlled ventilation (DCV).

Measurement and control of indoor CO2 concentration has been widely used as an indicator of human-related contaminant sources to control DCV systems, however, there are challenges associated with this approach. The main issue with the CO2 based DCV systems is the absence of information on the concentration of indoor gas phase contaminants and particular matter (PM), which could reach hazardous levels. Continuous emission of

volatile organic compounds (VOC) from building materials, furniture, carpets and released during human activities such as cooking, cleaning, or smoking cannot be detected with a CO2 sensor. The same situation exists with measuring the PM concentration during human activities such as cooking, smoking, and cleaning.

To address the above challenges, an array of gas and PM sensors could be used to measure concentration of selected indoor contaminants and to control the ventilation rate. In a residential application, the same sensor system could control the residential HVAC, fresh air system as well as range hood exhaust. The benefits of sensor based IAQ control becomes clear in indoor spaces where changes of CO2 concentration are too small for DCV system to be activated, but the concentration of other indoor air pollutants is high.

What Pollutant Should Be Measured?

In indoor environments hundreds of chemical compounds (VOC and inorganic), bioaerosols and PM can be found, however, it is not practical to effectively implement sensors to measure low concentrations of even a small percentage of the indoor air pollutants. One approach to this issue is to identify pollutants that are known to have an adverse effect on human health, and based on this identification to select appropriate sensors. The schematic process is shown below.

The selection of the most hazardous pollutants is based on the measurements of indoor concentrations, human exposure and health effects. The World Health Organization (WHO) has identified the following pollutants as being of most concern: benzene, carbon monoxide, formaldehyde, naphthalene, nitrogen dioxide, PM2.5, polycyclic aromatic hydrocarbon (PAH), radon and trichloroethylene.[1]

Based on measurements of the concentration of indoor pollutants in U.S. residences and the assessment of associated health hazards, a following list of nine pollutants was generated: acetaldehyde, acrolein, benzene, 1,3-butadiene, 1,4-dichlorobenzene, formaldehyde, naphthalene, nitrogen dioxide and PM2.5 [2]

When a different metric that took into consideration the cost associated with exposure to the indoor air pollutants, such as Disability Adjusted Life Years (DALYs), the list of the top five pollutants of most concern included: PM2.5, SHS (second hand smoke), radon, formaldehyde and acrolein.

Based on the above studies and identification of the most hazardous indoor air pollutants, it is not a simple task to select the appropriate sensors. Sensors to measure PM2.5, formaldehyde, nitrogen dioxide and VOCs should be considered as candidates for smart, demand-controlled ventilation systems. Also, countries with different lifestyles and environmental conditions could have a different list of major pollutants and different Exposure Limit Values (ELVs) that will need to be considered for a global market.

Low-Cost Sensors

During the last decade the improvement of existing technologies of PM and gas sensors has allowed the introduction of various types of low-cost sensors for air pollution monitoring. The majority of commercial low-cost sensors are based on the following principles of operations:

• PM sensor – light scattering

• Photo-ionization (PID) – UV light

• Electrochemical sensors – amperometric or potentiometric type

• Metal oxide sensors (MOx) – resistivity change

One of the critical sensor parameters is the low-level concentration detection limit. These limits of detection should be lower than the Exposure Limit Values (ELV) for specific pollutants.[3] Figure 1 shows the short- and long-term ELV for selected pollutants. For example, the long-term ELV for formaldehyde is 9 µg/ m3 and for PM2.5 it is 10 µg/m3. Sensors should be capable of measuring these concentration levels. Benzene as a one of the most critical, human carcinogenic pollutant has the long-term ELV = 3 µg/m3 per U.S. guideline and this is a significant challenge for low-cost sensors. It is recommended to reduce indoor exposure levels for benzene as low as possible. [1]

PM sensors. The reported performance of low-cost particle sensors across the literature is somewhat mixed, depending on the type of particle sensor and method of evaluation. There is a wide range of commercially available low-cost PM sensors which employ a light-scattering technique. These can typically detect particles with aerodynamic diameters ranging from 0.3 µm to 10 µm, and they transform the measured signal into a mass concentration. The limit of detection of low-cost PM sensors is typically between 5 to 10 µg/m3. The main drawback of using these sensors is the data quality, which may be sensitive to interference from environmental conditions, limited reproducibility, drift over time and the composition of the particles. If the aerosol being measured exhibits a different refractive index, density, shape factor or size distribution than the aerosol used for calibration, the measured concentration could be affected by these differences. Figure 2 illustrates this, it shows the measured concentration of cigarette smoke by two sensors, one calibrated with cigarette smoke and another one with different aerosol.

Formaldehyde sensors. Sensors used for measuring the formaldehyde concentration can be based on several principles, however, the most popular and feasible are the electrochemical sensors. They operate by reacting (oxidation – reduction) with the gas of interest and producing an electrical signal, which is proportional to the gas concentration. Since a current is generated in the process, the electrochemical sensors are often described as an amperometric type sensor.

Typical electrochemical sensors consist of a hydrophobic membrane, working electrode, counter electrode and layer of electrolyte. Despite their similar appearance, there are many different ways that electrochemical sensors are constructed. Their performance could be significantly different for each of these sensors, in terms of accuracy, sensitivity, selectivity, cross sensitivity, response time, and life expectancy. Detection limits depends on the structure of sensor and, typically, is in the range of 30 - 50 µg/m3. Temperature and humidity dependency as well as cross sensitivity are the major challenges affecting sensor accuracy. Figure 3 shows the response of two different electrochemical sensors to formaldehyde at different humidity levels.

VOC sensors. Electrochemical and semiconductor methods are the two most widely utilized gas sensing mechanisms. Metal oxide semiconductor (MOS) sensors are a resistive type sensors, since the resistance changes upon interaction with target gases. To enhance the sensor reactivity, the temperature of the sensing

p Figure 1. Exposure Limit Values for selected pollutants.

p Figure 2. Impact of calibration aerosol on measured concentration of cigarette smoke.

material is increased by using a local heater. The gas concentration is detected by measuring the resistance of MOS gas sensor. The most commonly used (MOS) gas sensors employ ZnO and SnO2 because of the good gas response, compact size and low cost. They are widely used to the measure concentration of VOCs in industrial applications. The temperature and humidity impact on sensor accuracy as well as the cross sensitivity are the major drawbacks. The presence of hydrogen sulfide, ammonia and alcohol in ambient air also strongly affects the accuracy of the MOS sensor. Figure 4 illustrates the impact of relative humidity on VOC measurement.

Sensor Input

The main challenge with the measured concentration of indoor air pollutants is the creation of a metric which could be used to communicate with the demand – controlled ventilation system. One approach is the direct comparison of the measured concentration values (C) to the ELV for the specific pollutants.

When: Ci[µg/m3] > ELVi or Ci[µg/m3]/ ELVi > 1 activate ventilation system, fresh air or range hood exhaust

For example, the algorithm will trigger activation when measured concentration of PM2.5 is greater than the ELV = 10 µg/m3. Another approach is to create a simple multipollutant index (X) by combining all measured pollutants, similar to the Indoor Air Quality Index concept.

X = ∑ Xi = ∑ λi (C/ELV)i = λ1(C/ELV)1 + λ2(C/ELV)2 + λ3(C/ELV)3 + … where: λ is the weighting factor assigned based on priority with ∑λi = 1 i – specific pollutant such as PM2.5, formaldehyde, CO2

The simple, algebraic sum is an elegant way to include inputs from all sensors, however this may not be the optimal way to describe the interaction effects among the various pollutants. Interaction between pollutants may result in health effects that may be additive, synergistic, or antagonistic. The additive effect can happen when the exposure to several pollutants produces an effect equal to the sum of the effects of individual pollutants. Synergistic effects are the most challenging cases, since the total health effect is greater than the sum of the effects of each acting alone.

Conclusion

Low-cost particle and gas sensors are an attractive addition to the demand-controlled ventilation systems and, potentially, for future applications such as residential fresh air systems and/or range hood exhausts. Despite all the limitations, such as cross sensitivity issues, inadequate limits of detection or the impact of environmental conditions, low-cost sensors can play an important role in IAQ application.

The majority of current portable air cleaners are equipped with at least one sensor, or array of sensors. These sensors not only can measure and display the pollutant concentration, but also trigger an action such as changing flow rate, and potentially, to detect the state of filtration system. Even if the triggered action occurs at a

different concentration than the ELV, the benefits are evident. As an example, we can look at the cooking events when the PM2.5 concentrations can exceed 1000 µg/m3. Due to higher detection limit, PM sensors could activate a cleaning system or exhaust fan at higher concentration that the recommended ELV = 10 µg/m3, but the exposure to high concentration will be significantly reduced.

Low-cost air pollution sensors can also be incorporated into more complex monitors, which can provide users with useful information regarding concentration levels of some air pollutants, and may help them to take actions to improve indoor air quality.

Dr. Thad Ptak has over 30 years of experience in filtration technologies, aerosol science and indoor air quality. He has conducted extensive research in the areas of development of filter media and filters, portable air cleaners, indoor air quality, sensors for IAQ and instrumentation for particle generation and measurement.

1. WHO guideline for indoor air quality: selected pollutants, 2010.

2. JM Logue at el., Hazard assessment of chemical air contaminants measured in residences, Indoor Air, 2011.

3. AIVC Contributed Report, 2017.

p Figure 4. MOS sensor at different RH.

p Figure 3. Formaldehyde sensor at different RH.

STORMWATER

Ozone’s Next Frontier

Ozone and AOP Could Help Rainwater and Runoff Play a Bigger Role in Reuse

By Jim Lauria

Ozone and rainwater have always had a close connection, as anyone who has smelled the distinctive odor of ozone after a thunderstorm can attest. But the next phase of the ozone/rainwater connection could be at hand as the water purifying power of ozone is harnessed to treat rainwater for reuse.

The need is immediate and growing, thanks to a rising population, urbanization, and a changing climate. Many parts of the world are experiencing increasing variability in rainfall, flashier storms, and greater water demand. At the same time, the vast spread of impermeable surfaces – including roads, parking lots and roofs – require stormwater to be captured, stored, moved, and used elsewhere. It is no longer enough, or even possible,

in many areas to simply let rain soak into the ground. Today, storms become floods more quickly than ever, and we must actively control and manage stormwater to avoid overwhelming damaged watersheds. We must also be cognizant that the surfaces from which we harvest rainwater, or the roiling floods we seek to control, contribute pollutants to their systems. As we take on the responsibility for managing stormwater, ozone and

aeration will become an ever-larger part of water reuse.

Ozone, or O3 – a radical containing three oxygen atoms rather than the usual, stable two-atom form that we breathe – is extremely reactive. Its third oxygen atom is extremely prone to jumping off the ozone formation to join another molecule, often cleaving the target molecule to make the reaction. The result is oxidation, a process that can burst microbes, destroy biofilm, and neutralize taste and odor compounds instantly. In fact, ozone is second only to fluorine for oxidation potential, and is significantly more reactive than hydrogen peroxide and chlorine. Contact time is negligible, and excess ozone returns quickly to the more stable, environmentally benign O2 form in moments.

In addition, unlike chemical additives that must be transported and stored carefully, ozone can be produced on-site in a high-energy chamber where liquid oxygen or air are exposed to high voltage. It is truly lightning in a bottle.

Over a Century

Ozone has been used in drinking water treatment since the first commercial installation at a water utility in Nice, France, in 1906. It has proven itself over more than a century around the world in controlling taste and odor compounds, bacteria, viruses, and more. Early ozone treatment systems employed passive diffusion, such as fine bubble emitters in deep contact basins, to transfer low

concentrations of ozone into target water. Under the pressure created by the weight of deep water, ozone bubbles can be absorbed into the pool as they float toward the surface.

In recent decades, improvements in ozone generators have dramatically increased ozone concentration, making it more efficient to use the flow of water through venturi injectors to create a vacuum that draws in ozone and mixes it thoroughly with the stream. The result is nearly instant treatment in shallow contactors or even just a few meters of pipeline. Mass transfer efficiencies exceeding

95% are possible through venturi injection systems, minimizing unnecessary ozone generation and energy use, and maximizing the control of pathogens and taste and odor compounds.

Another high-efficiency innovation has also helped bring ozone to the fore: combining ozone with UV disinfection or hydrogen peroxide yields advanced oxidation processes, or AOPs. Ozone can also be paired with biologically active filtration (BAF) systems for multi-layered purification.

Many of the same microbes that present health risks in drinking water – including Giardia, Cryptosporidium, Campylobacter, Rotavirus, and Legionella – are concerns in stormwater, particularly when the water is aerosolized into particles that can be drawn into the lungs. Aerosols can be formed through sprinkler application, water features or aeration jets in retention basins, or even flushing toilets. Exposure to Legionella through aerosolized water is no idle worry – in 2019, more than 130 visitors to a state fair in North Carolina were sickened by Legionella, most likely after they passed by hot tubs on display. Four died. The threat is persistent – the U.S. Centers for Disease Control estimates that Legionella is

p Ozone is second only to fluorine in its oxidation potential, and can be manufactured on-site as needed, eliminating the need to transport and store toxic chemicals.

p A powerful oxidant, ozone ruptures cell walls on contact, while chlorine must diffuse through the wall to kill bacteria.

Ozone has been used in drinking water treatment since the first commercial installation at a water utility in Nice, France, in 1906. It has proven itself over more than a century around the world in controlling taste and odor compounds, bacteria, viruses, and more.

Filtration Adhesives VALUE-ADDED

responsible for 8,000 to 18,000 hospitalizations per year.

Highly Effective on Legionella

Storage tanks and pipes used for rainwater are also prime environments for the formation of biofilm, durable coatings that can shelter pathogens from disinfectants like chlorine or bromine. Biofilm has been implicated in severe outbreaks of Legionnaire's disease and the milder Pontiac fever, both caused by exposure to Legionella bacteria. Legionella is commonly found in rainwater storage tanks, drainage piping that contains stagnant water, and stormwater retention ponds, as well as cooling towers and other structures where biofilm can proliferate.

Fortunately, ozone is highly effective in controlling Legionella and other bacteria. In fact, while chlorine must diffuse through bacterial cell membranes to destroy the pathogen's DNA, ozone bursts the cells themselves in an immediate, violent reaction.

Using the flow of water pumped from a rainwater storage tank or retention basin, ozone can be drawn into carefully engineered venturi injectors and mixed thoroughly with the water. Treated water may be returned to storage, used for a wide range of applications — from irrigation to decorative fountains or more — or injected to treat a larger volume through a pipeline flash reactor (PFR), contact basin, or manifold in a sidestream injection system.

A Wide Variety of Polymers for Your Filtration Needs…

Epic Resins’ epoxy and polyurethane solutions have solved complex filter manufacturing challenges for decades. Our experts partner with you, leveraging our experience to recommend products or formulate solutions designed for:

Moldable End Caps | Seam Sealing | End Cap Adhesives

Potting & Casting Compounds

AOP systems that combine ozone with UV or hydrogen peroxide treatment can provide an even higher level of purification for more sanitary uses of stormwater. The same efficiencies can apply: a venturi that uses the flow of water through the injector to draw in ozone from a generator and mix it thoroughly, a few feet of pipe or a small basin for a contactor, and a simple destructor unit to address any residual ozone.

In turbid stormwater, ozone treatment can remove cloudiness and make UV more effective as a second layer of disinfection, or minimize solids that can tie up hydrogen peroxide or chlorine.

Computational fluid dynamics (CFD) is another powerful tool that has ampli-

fied the effectiveness of ozone systems, allowing engineers to fine-tune designs to maximize gas transfer, guide pump size and placement, and optimize energy efficiency. In the case of pipeline flash reactors, nozzles can be sized and precisely placed to make sidestream injection systems as efficient as possible; static mixing vanes can be placed and angled

to turn the flow of water into a powerful mixing force. Through CFD, injection systems can be designed with extremely high turndown capabilities, allowing engineers to prepare for a wide range of flows from gentle rains to violent floods.

The same technologies – venturi injection, pipeline flash reactors, and CFD – can be employed in simpler aeration

projects, allowing communities or industries to add dissolved oxygen to stormwater in preparation for environmental release. In the end, the goal is the same: permitting the safe, effective, efficient reuse of rainwater and stormwater for a wide range of applications, while safeguarding public health. Now, more than ever, our future depends on it.

Jim Lauria is the Vice President of Sales & Marketing for Mazzei Injector Company, a fluid design company that manufactures mixing and contacting systems for a wide range of water treatment applications. Since graduating with a Bachelor of Chemical Engineering degree from Manhattan College, he has traveled the world benchmarking and documenting the best global water management practices. He can be contacted at jlauria@ mazzei.net.

Save Labor, Boost Throughput & Improve Quality!

Elsner's automated filter manufacturing machinery helps you save time and money. From unwinding and folding to cutting and gluing to pack building and robotic glue applications, we make every step of the way easy to boost your productivity.

p A simple rainwater ozonation system injects ozone through a venturi to control pathogens – including Legionella – and taste-and-odor compounds.

RAINWATER Diversion Strategies

By Dave Molinari

Rainwater quality can vary depending on the surface area it falls on. Initially, rainwater can collect oils, contaminants, and chemicals as it touches the ground. However, as it continues to fall, it picks up fewer foreign substances, resulting in cleaner water. As a result, the first 1/10th of an inch of rainwater requires different treatment than the rest. Fortunately, technology exists to treat the initial rainwater, and it has been utilized in certain parts of the country for some time. However, as more people become aware of this functionality, its applications are gaining popularity all across the country.

The concept of diverting portions of rainwater was first developed in the late 1960s in Los Angeles, where the unique geography of the area causes water to be squeezed from the atmosphere as storms move in from the ocean and meet the elevated land. Although rain is infrequent in this region, it is crucial to capture as much of it as possible for future use in groundwater basins. However, during storm events, the existing wastewater system can become overwhelmed. All flushable water runs through a wastewater treatment facility before being discharged into the ocean. The influx of freshwater from a storm event, known as clean water incursion, can disrupt the wastewater treatment process, leading to an imbalance in the system.

The challenge at hand was not an easy one to solve. The objective was to figure out how to separate a portion of the rainwater and send it to the wastewater treatment plant while directing the remaining water to the groundwater basins or ocean. To address this problem, a specialized technology was developed. The technology is designed specifically for controlling drain diversion and is comprised of three key components: the detection device, pilot stations, and valves. The detection device was created to identify when 1/10th of an inch of rainfall occurs. This amount of rainfall typically contains high levels of contaminants and bacteria, making it unsuitable for the groundwater basins and requiring treatment before being discharged into the ocean.

To ensure durability, the detection device must be built using sturdy materials that can withstand harsh conditions. Rainwater is collected in a chamber, and a conductive level sensor detects the volume when it reaches 1/10 of an inch. This signal is then sent to a pilot station.

Mounted inside the pilot station is a level controller that changes state. It sends a small current to the probe, and when the water comes into contact with the probe, the circuit is completed, and the contacts switch in the controller. Most importantly, this process is highly reliable.

The pilot station operates in two modes: normal mode and divert mode. In normal mode, when it is not raining, the valve is set to direct the flow to the sewer system. An automatic timer opens the solenoid valve for 15 minutes every 10 hours. When it is raining and the pilot station is in divert mode, the valve directs the water to the appropriate destination, either the ground water basins or the sewer system for treatment.

Once rainfall reaches the designated threshold, the pilot station is switched to divert mode, triggering the controller to

p Used in conjunction with the RainSwitch to indicate status, control, and reset the system after the rain event has concluded. Available in both Manual and Automatic Reset versions to meet various agency requirements.

All flushable water runs through a wastewater treatment facility before being discharged into the ocean. The influx of freshwater from a storm event, known as clean water incursion, can disrupt the wastewater treatment process, leading to an imbalance in the system.

alter the valve's state and direct the rainwater to the storm drain system. After 10 hours, the automatic timer resets the detection system, causing the valve to return to normal mode and redirect the flow to the sewer system until the next 1/10th of an inch is detected. This cycle repeats until the rainfall stops and the system returns to normal mode.

In most cases, butterfly or ball valves are utilized alongside a clarifier for the diversion process. However, there are instances where a sump pump can be employed to regulate the flow to the sewer or storm drain, depending on the plumbing arrangement of the drainage system. The best design for the situation at hand must be determined.

Are There Applications Outside of a City Like Los Angeles?

Absolutely. This technology can be applied in various places across the country – for instance, in heavily trafficked patio areas of large residential or commercial buildings, where water runoff is diverted to the sewer system or the building's rain gutter system. Incorporating this water diversion technology can ensure that the first 1/10th of an inch heads to the sewer system while the rest is utilized for the building's intended purposes.

In the southern United States, cisterns have become increasingly popular,

The RainSwitch is made of stainless steel to ensure long life against harsh environments. The RainSwitch is designed with a 14” funnel to collect the falling rain. It is connected to a diversion system, directing the subsequent run off to the storm drain system. The diversion system typically consists of a butterfly/ball valve adjacent to a clarifier, or sometimes a sump pump is used which controls the flow to the sewer or storm drain. The system design depends on the plumbing arrangement of your drainage system.

 Jensen Instrument Co. provides 2- & 3-Way Butterfly & Ball Valves for diversion of flow from sewer to the storm water piping which include wiring schematics and installation recommendations with RainSwitch.

especially in areas where there are mandates for parking lots to have a cistern tank for capturing water runoff for irrigation purposes. However, it can be challenging to determine when the tank is full and requires diverting water elsewhere to avoid street flooding and clogging in the storm drain. Fortunately, water diversion control technology can be utilized to address this challenge, ensuring that excess water is directed to the appropriate location.

It is crucial to explore all options available for rainwater diversion, whether to comply with city ordinances or to utilize the collected rainwater for various purposes. Awareness of available technology can help ensure that rainwater is appropriately managed and diverted to prevent flooding and contamination.

Dave Molinari is a Technical Sales Engineer for Valin Corporation, a leading technical solutions provider for the technology, energy, life sciences, natural resources and transportation industries. Valin offers personalized order management, on-site field support, comprehensive training and applied expert engineering services utilizing automation, fluid management, precision measurement, process heating, and filtration products. For more information, please visit www.valin.com.

By Marc McKenna

QUALITY FACTOR

The Importance of a Quality Assurance/Quality Control Program When Purchasing Fabric Filters

The value of fabric and bag Quality Assurance/Quality Control program, bag installation oversight, and bag monitoring program increases as the code requirements become more stringent. The intrinsic value of the QA/QC program is driven by the fact that the failure of even one bag can cause dust contamination on the clean side of the baghouse. This, in turn, leads to widespread premature bag failure and/or pressure drop increases. Recent new fabric and bag QA/QC programs have detected membrane failures, out of spec strength and permeability, fabric shrinkage concerns, bag punctures and significant dimensional and construction issues.

The following are a brief description of the test methods currently employed in a QA/QC program.

Air Permeability

The air permeability is used to determine the amount of air that can flow through a given cloth area. Permeability is defined in ASTM Standard D737 as the rate of air flow passing perpendicularly through a known area of fabric which is adjusted to obtain a prescribed air pressure differential between the two fabric surfaces.

Mullen Burst

The Mullen burst strength test, described in ASTM Standard D3786, is designed to show the relative total strength of fabrics to withstand severe pulsing or pressure. Fabric strength is determined by measuring the pressure required to rupture the specimen from inflation of an expandable diaphragm.

Tensile Strength

The tensile strength test provides data on fabric strength and elongation. The ASTM Standard D5055 provides raveled strip (woven fabrics) and cut strip test procedures (nonwoven and felted fabrics) for determining the breaking force and elongation of most textile fabrics.

M.I.T. Flex Endurance Test

The M.I.T. flex endurance test primarily measures the relative value of fabric to withstand self-abrasion from flexing by measuring the number of flex cycles necessary to break a fabric sample. The test

FABRIC SPECIFICATION

Fabric type

The failure of even one bag can cause dust contamination on the clean side of the baghouse.

THREAD SPECIFICATION

Thread type Ptfe coated fiberglass, type e-12 Construction 150 2/2

Nominal diameter .014 inches Tensile strength 12 lbs (min.) Ptfe organic content (loi) 14% (min.)

Type of weave

Yarn

Yarn designation Warp 75 1/2 filament FILL 75 1/4 TEXTURIZED

Finish (base fabric)

Permeability

cu. Ft. Gas per sq. Ft. Cloth @ 0.5 in. W.g.

Tensile strength Warp 500 lbs/in (min.)

FILL 350 LBS/IN (MIN.)

Mullen burst 800 psi (min.)

Mit flex

Warp 8000 flexes (min.)

FILL 2000 FLEXES (MIN.)

Filtration performance <0.0001 gr/dscf

Microscopic (reference only)

method is described in ASTM Standard D2176 which is the standard method for testing the folding endurance of paper. The fabric samples are tested in both the warp and fill directions.

The M.I.T flex test has traditionally been used to help determine the rate of deterioration of woven fiberglass bags used in the coal-fired utility boilers due to the inherent abrasiveness of glass fibers. ETS has also found the M.I.T. flex test to be very useful in the evaluation of many felts and their ability to withstand flexing against a wire cage during pulse cleaning cycles. For nearly all filter bag fabric types, this test can be a leading indicator that the fabric is nearing the end of its useful service life.

Filtration Performance

The filtration performance test apparatus developed in Germany measures filter media performance under defined conditions with regard to filtration velocity, particle size distribution, and cleaning requirements, simulating actual baghouse conditions.

Fourier Transform Infrared Spectroscopy (FTIR)

FTIR is a technique that uses infrared

light to observe properties of solid, liquid, or gas. In infrared spectroscopy, IR radiation is passed through (transmitted). The resulting spectrum represents the molecular absorption and transmission, creating a molecular fingerprint of the sample. FTIR analysis results are generally utilized for identification of materials of construction (e.g., fiber type, thread type) of filter bags and/or evaluation of contaminants.

Comprehensive Monitoring Programs

Long-term monitoring programs compliment QA/QC programs. All the strength and flow tests should be done in conjunction with each other periodically in order to develop the loss of strength and flow trend lines over time. The testing program can identify when the bags are approaching end of life and higher risk of failure, but cannot predict the exact timing of the end of life of the bag set. Permeability measurements of used bags can, by varying the amount of vacuuming, help to determine if the bags are gradually blinding (losing permeability). Used bag test values are compared with the original clean fabric test values to show rate and level of deterioration.

Conclusion

Today the primary reasons for conducting fabric and bag QA/QC include:

1) Minimize baghouse and production downtime by insuring that the specification is met and related bag failure precluded.

2) Protect the user in the event of warranty issues by providing baseline data.

3) Provide an unbiased third-party assessment of faulty fabric and finished filter bags.

Marc McKenna is in his 20th year at ETS, Inc. where he became President in 2013. Marc has varied experience in business administration, project management, fabric filter and environmental testing plus safety coordination. ETS is currently celebrating its 50th year serving Utilities and Industry with Training Troubleshooting and Testing. He can be reached at mmck@etsi-inc.com.

Smarter Filtration Rhetoric

By Dr. Iyad Al-Attar

While the pandemic granted air quality tremendous attention, air filter selection and installation in HVAC systems remain on the back burner. Filtration systems installed in smart cities to provide a built-environment that is clean and green still need the charm and leadership required to make air quality a global priority. The time to halt conventional filtration methodologies and maintenance shortcuts is now.

The best way to grant air filtration the attention it deserves is to highlight its importance to our well-being, health, and safety of human occupants and the equipment it protects, such as heating, ventilation, and air conditioning (HVAC) systems. The premise of installing HVAC equipment is to provide human occupants with the required thermal comfort while supplying enhanced indoor air quality. But that has its energy implications as air conditioning systems and electric fans used for thermal comfort account for nearly 20% of the total electricity installed in buildings worldwide today, according to a report published by the International Energy Agency. Furthermore, the demand for HVAC systems will continue to rise due to rapid urbanization and population growth, leading to a surge in energy demand. The United Nations report projects that 2.5 billion people will reside in urban

areas by 2050 through the construction of megacities representing 68% of the world population compared to 55% today [1] . According to UN-Habitat, cities currently consume 78% of the world's energy and produce more than 60% of greenhouse gas emissions [2] .

The rising demand for HVAC generally strains electricity systems in many countries and drives up emissions. Without responsible fossil fuel combustion and power usage to reduce our environmental footprint and promote energy-efficient air conditioning equipment, the global demand for power generation will continue to increase for decades to come. Furthermore, these cities also require better indoor air quality (IAQ), not just simply thermal comfort. Research has suggested that inappropriate and insufficient filtration and ventilation can lead to deteriorated IAQ in naturally and mechanically ventilated indoor spaces [3]. Other studies have shown that poor IAQ in densely occupied indoor areas can impact occupants' productivity, cognitive performance, and physical and mental health [4-10]. Mitigating air-quality challenges requires firm policy interventions highlighting the role of advanced filtration technologies and energy-efficient HVAC systems. Recently, pandemics and environmental disasters have continued to shape our mitigation

philosophies and actions to tackle air quality issues.

Filtration For the Built Environment

Air filtration is a great tool to separate and retain particles and other pollutants on or within its filter media. However, appropriate selection, installation, and employment of various filter technologies are critical in capitalizing on their capacity to perform the intended job. Air filter performance lies at the core of understanding the function of filtration needed for a given application and the form in which it is performed and delivered. However, it isn't easy to make the role of air filtration well pronounced when filter suffer from common chronic failure as shown in Figure 1. The momentum air filtration gained during the pandemic should represent a historical milestone rather than a volatile chapter. Therefore, implementing innovative filter approaches is essential to changing the complexion of air quality and the way we perceive filter performance.

Furthermore, emphasizing better air quality and a healthy built environment requires allocating funds for aerosol filtration research and atmospheric aerosol characterization. Combining such research with continuous outdoor and

Dr. Iyad Al-Attar

p Figure 1: Various examples of filter failures during operating in HVAC equipment.

indoor aerosol monitoring will prove invaluable in assessing air filter performance when challenged with various outdoor concentrations of particulates and gaseous contaminants. This becomes of critical importance as an adult typically inhales 17,000 liters of air daily, depending on the breathing patterns of each individual. Ultimately, this renders a low airborne contaminant concentration of many inhaled pollutants extremely hazardous over relatively short exposure durations. Therefore, inappropriate filter selection exposes the indoor environment and its human occupants’ respiratory systems to many pollutant types. Furthermore, poor filter performance impedes the ability of HVAC equipment to deliver appropriate heating and/or cooling needed for occupants’ thermal comfort.

Appropriate filter selection requires a fundamental understanding of the physical and chemical characteristics of the pollutants of interest. Ultimately, delivering the proper quality and quantity of clean air to the built environment requires energyefficient air filtration solutions. However, while the nature of filter selection for each application may appear standard, the filtration dynamics will probably change. This is particularly true as market dynamics may shift as customer preferences evolve, filtration technologies advance, and eventually, new products are released.

Filter Media

An integral element in the anatomy of an air filter is its media. Filter media represents the building blocks of an air filter. Their properties control the filtration process, how the filter performs, and whether the particles will deposit on the depth or surface of the filter through dendrite or cake formation, or pass completely through the filter. However, the inhomogeneity of filter media continues to pose a tremendous challenge to filter performance prediction, as shown in Figure 2. Filter media are expected to be permeable, efficient, and have

the structural integrity required to sustain the air flow without undergoing a substantial deformation that alters performance characteristics.

Air Filter Performance Prediction

The essence of selecting appropriate air filters for HVAC applications lies in understanding the challenges in a given geographic location, climate, and operational conditions. These factors can have their

fingerprints on the selection and stages required to render outdoor air safe to supply indoors.

One of the main challenges in air filtration is the performance deviation of air filters from that predicted by laboratory results. In addition, the variation in particle characteristics in terms of density, size distribution, and concentration can alter the filtration dynamics of particle loading and eventually lead to premature clogging. For example, given the air filter design and media selection, excessive particle concentration could lead to surface deposition of particles on a depth medium leading to substantial permeability reduction. As shown in Figure 3, particles can also bridge to form tree-like dendrites to form an eventual cake layer.

Therefore, one of the primary issues in air filtration is highlighting prefiltration’s role rather than relying single-handedly on one filtration stage to do the job. The importance of filtration stages is paramount since the dominant mechanism/s is/are influenced by particle size and their distribution, as shown in Figure 4. Filter loading by particle capture is characterized by dominant mechanisms and is illustrated in Figure 5 based on the dominant mechanisms. The filter efficiency and mechanism of capture depend upon many interrelated factors, such as aerosol size, face velocity, density, and fiber packing in the media. In addition, adjacent fibers, dendrite formation, and fiber charge influence the loading of ‘real’ filters.

Filter Loading and Clogging

Air filters installed in HVAC applications are depth filters used predominantly to capture aerosols utilizing fibrous filters. Depth filters go through stationary, nonstationary, transition, and surface-deposition stages. In depth filtration, particlecake formation signifies that filters need replacement or maintenance. On the other hand, early dust-cake formation is required in surface

p Figure 2: Scanning electron microscope image highlighting the inhomogeneity of fibrous filter media. [11]

p Figure 3: Examples of dendrites and dust cake formations on filter media. [11]

q Figure 4: Illustration of common filtration mechanisms.

filtration to attain higher efficiencies. The variation in the filter medium pore structure as particles continue to deposit in its interstitial spaces causes permeability reduction and alters the flow dynamics leading to a pronounced rise in the filter’s pressure drop.

As a result, increasing the filter’s resistance compromises the flow rate delivered to the indoor spaces, and the human occupants may begin to feel thermally uncomfortable. In addition, excessive human occupancy in the built environment will increase the moisture level indoors, which would challenge the installed HVAC equipment to achieve the thermal comfort required while delivering sufficient clean air indoors. Excessive moisture also influences filter loading and performance and fosters the potential for odor development and microorganism growth.

The particle loading of a typical fibrous filter structure is shown in Figure 6 as it progresses through its lifetime from sta-

tionary to nonstationary, to transition, and eventually to clogging. On the other hand, Figure 7 shows premature dust cake formation on a typical fibrous filter used in HVAC equipment compared to a stationary phase of filtration of a similar filter. Ideally, extending the stationary stage of the filter’s lifetime is critical as the depth deposition of particles occurs at the negligible rise in pressure drop. In addition, premature clogging of air filters steers away filter performance from energy-efficiency considerations.

Particle Size and Particle Loading

In the global battle against COVID-19, when nothing seemed to work as far as protecting humanity from infections, some filtration solutions finally did. Nevertheless, unfortunately, the tremendous losses in human lives and the impact on the global economy have echoed the rhyme of enhanced air quality. Regardless, air filters can perform and, in some instances, outperform if the ideal operational conditions are facilitated, such as leak-free installation and subjecting them to a rated flow rate.

Understanding that the outdoor environment filter operates from within and where the HVAC system draws air indoors is essential to avoiding performance deviation. Premature clogging leading to shortened filter lifetime has financial implications, whether by more frequently replacing filters than planned or inducing damage to the HVAC equipment. Furthermore, when particles start to seep indoors, they expose human occupants to adverse health risks and accelerate the facility that aging HVAC systems aim to protect.

The overall efficiency of a filter is based on the combination of the dominant collection mechanisms. Therefore, particle size is a fundamental parameter in aerosol properties and highly influences filter performance. To illustrate such effect, two similar E10 V-bank filter cartridges (Figure 8) were loaded with SAE Fine and Coarse synthetic dust in laboratory settings, respectively. Figure 9 illustrates the visual difference in particle size between the two dust types. The comparison in the pressure drop response due to their loading is shown in Figure 10, indicating that SAE Fine dust particles were more penetrating than SAE Coarse particles. Fine dust particles tend to occupy more interstitial spaces inside the filter medium, leading to substantial alternation in the pore structure and hence, the pressure drop of the filter increases.

Air Quality for Smart Cities

Smart cities’ goals are attained faster when the interest among sectors is common, targets are clear, and funds and resources to execute the integration plans are available. Moreover, implementing air quality solutions available today is an added value to the built environment and the well-being

p Figure 5: Illustration of filter loading by particle capture characterized by dominant mechanisms.

p Figure 6: Filter loading progression throughout the lifetime of particle loaded fibrous filter.

p Figure 7: Comparison between particle depth (Right) and surface (Left) deposition. [11]

 Figure 8: V-bank filter with four-openings and eight pleated panel of fibrous media. [11]

of human occupants. A recent case study has highlighted the benefits of continuous rather than periodic air quality monitoring in densely populated call centers [12] Experimental work has highlighted the deterioration of air quality when staff arrive at work and then return to acceptable settings when they leave. Although staff interactions and breathing patterns significantly affected the indoor air quality, the data collected helped the facility management make appropriate maintenance decisions relevant to upgrading air filters, increasing ventilation rates, and installing chemical filters to treat the volatile organic compounds (VOCs) concentration existing in the center during office hours. As illustrated in Figure 11, the PM1 and PM2.5 concentrations were reduced after the filter upgrades to a minimum and maximum of

zero and one µg/m illustrates the air quality monitoring com parison of a call center between working days and weekends for VOCs and carbon dioxide (CO

Globally, China, Singapore, Korea, Japan, and Finland are leading toward more sophisticated use of the Internet of Things (IOTs) to control air quality. Integrating air quality monitoring systems to measure, track, and mitigate pollutant concentrations, maintain thermal comfort, and operate equipment through energyefficiency strategies will prove invaluable.

The Emerging Eureka Moment

It is challenging to fight a eureka moment when air quality becomes a pillar of the indoor environment and the global economy. Overlooking the critical role of inhaling better air quality and allowing human exposure to pollution is a misdemeanor. Could it be that having

pandemics is just like sun and moon eclipses, and encountering the next pandemic is simply a matter of time. The order of the day is not to have any more pandemics as opposed to “let’s be ready for the next one.” This would be facilitated by understanding the importance of available filtration technologies and realizing the potential of their employment in indoor environments.

Recalling that people are one of the three pillars of sustainability alongside planet and profit, embracing “human-centric” air quality models will save many lives and outweigh the financial impacts. Neglecting to control the risks of pollution and exposure and failing to utilize secondto-none HVAC systems hinder the well-being of humans. We must decide whether to embrace sustainable air quality business models and pay the fees or the fines for not doing so. The challenges ahead are grand; the rising tide of air pollution is evident; measures are still evolving, but the next pandemic may be approaching.

Dr. Al-Attar is a mechanical engineer and an independent air filtration consultant. He is also a Visiting Academic Fellow in the School of Aerospace, Transport, and Manufacturing at Cranfield University, consulting for air quality and filter performance relevant to land-based gas turbines. Dr. Al-Attar is the strategic director, instructor, and advisory board member of the Waterloo Filtration Institute. In 2020, EUROVENT Middle East appointed Dr. Al-Attar as the first associated consultant for air filtration affairs. His expertise focuses on designing and performing high-efficiency filters for HVAC and land-based gas turbine applications, particularly on the chemical and physical characterization of airborne particles. He has authored many articles on air quality, filter design, performance, particle characterization, and climate change. He can be reached at iyad@wfinstitute.com.

p Figure 9: Scanning electron microscopic comparison showing SAE Fine and Coarse dusts. [11]

cartridge after loading them with SAE Fine and Coarse dusts.

p Figure 12: Air quality monitoring comparison of a call center between working days and weekends (VOCs & CO2). [12]

p Figure 11: Air quality monitoring of a call center pre-, during and post-office hours. 1 and PM2.5). [12]

[1-12] All references are found in the online article at filtnews.com.

Filtering

Ideas & Innovation

FILTECH 2023 Provides a Strong Signal For Growth of the Filtration and Separation Sector

FILTECH 2023 did not disappoint with an abundant array of research and development, new and triedand-true products, as well as networking opportunities. Approximately 16,750 participants visited FILTECH 2023 – a strong signal for further growth of the worldwide filtration and separation sector. The number of participants not only reached pre-pandemic levels but exceeded it.

Attendees came from 80 nations and all continents. This intercultural experience provided a unique platform for attendees’ peer networking and learning opportunities from a global perspective. Exhibitors enjoyed a chance to generate new business. Many exhibitors used the show not only for personal exchange with customers and interested parties, but also for the launch of new products and services.

“The success of each event is measured by the experience of the participants and exhibitors,” says Suzanne Abetz, Managing Director. “For FILTECH 2023, the feedback is very positive: Over 90 percent of exhibitors rate the professional qualifications of visitors to their stand as high. This experience has a very positive impact on the market. By visiting FILTECH, participants

ensure that they receive the right solutions to strengthen their business. For exhibitors, this means they receive successful leads and find access to customers who are a perfect match for their offering.”

Abetz says participants are closely connected to the industry, and understand current and future challenges. “Together with our scientific advisory board, we are closely monitoring developments in the market to set the right priorities and focus on current topics. Also helpful for participants is the high proportion of various research institutions among the exhibitors. The areas of products and services as well as research and development intertwine.”

Research – Star of Presentations

With 160 presentations, FILTECH 2023 is an important platform for scientific exchange on filtration and separation. Speakers covered topics across all disciplines, from solids separation to solidliquid separation to the separation of gases. Practical research included topics from the use of electrostatically charged nanofiber filters for filtering submicron and nano aerosols, to studies on particle interactions in solid-liquid separation processes using the CFD-DEM coupling method.

AGXX

In a series of interesting papers on water purification, Dr. Marie-Lena Harwardt of Heraeus Precious Metals introduced AGXX, a new antimicrobial technology which is based on reactive oxygen species produced from water and oxygen by a catalytical reaction supported by two precious metals. Additionally, a microelectric field between the two precious metals increases the antimicrobial effect.

Heraeus Precious Metals, headquartered in Hanau, which has annual sales of approaching €30 billion and is one of the top ten family-owned companies in Germany, has high expectations for AGXX, particularly as a replacement for silverbased antimicrobial technologies. Many current antimicrobials based on silver are not in step with the latest European Union legislation on biocides and face the prospect of being banned from the market.

p Robotek demonstrated their Mixing Head automated process. They can configure dispensing solutions with a suitable one-component-dispenser or a multicomponent-dynamic or static-mixing head based on application requirements.

The conference keynote speech by Professor Hermann Nirschl from the Karlsruhe Institute of Technology (KIT) was certainly a highlight, illustrating the importance of digitalization for filtration and how far the industry has developed. He highlighted the basics of autonomous processes and their implementation in separation devices like centrifuges, noting that among other things, in situ characterization devices will become more and more important for the realization of a “model predictive control” strategy. This not only allows an automatic optimization of the target variables, but also helps to ensure a high resource efficiency according to raw materials and energy consumption.

AGXX is not based on the release of any metals or harmful compounds and to date, has shown antimicrobial efficacy against over 130 microorganisms including bacteria, viruses, algae, and fungi, among others silver-resistant E. coli strains, methicillinresistant S.aureus (MRSA) CoV2 viruses.

The technology initially used inorganic carrier powders, such as activated coal, aluminum oxide or other carrier materials well suited for incorporation into textile filters based on polyamide and PU foam as well as in coatings and individual fibers.

It has also been successfully applied to various types of activated carbon granules and pellets for easy incorporation into activated carbon-based water filters.

AGXX shows excellent antimicrobial efficacy in laboratory tests and samples, and is being tested for wastewater treatment and purification systems for swimming pools.

p Dr. Anthony Stickland of the University of Melbourne, Australia, spoke to mineral tailings filtration, and lessons learned from wastewater sludge filtration.

PAC Pre-Filter

Helmut Geers, of Hofmann Maschinen und Anlagenbau, based in Worms, Germany, provided details of a project with the Technical University of Braunschweig aimed at the more effective removal of trace substances found in municipal wastewater – pharmaceuticals, detergents, biocides, anti-corrosion agents etc., as well as microplastics.

The use of pre-coat filter technology combining powder activated carbon (PAC) with cellulose achieves particle retention

down to the sub-micron range with very good elimination of trace substances.

Modifications of the pre-coat filter technology are currently being tested. “Based on a first economic evaluation, the specific treatment costs are moderate and competitive compared to established technologies for trace pollutants removal and our system would require a lot less space at a wastewater plant,” Geers said.

Ahlstrom Disruptor

Erik Nelson of Ahlstrom described ongoing improvements to the company’s Disruptor wetlaid electro-positive nonwoven technology which was first introduced over a decade ago.

Due to its open media structure, Disruptor can be used in a very wide range of end uses covering both pressurized water purification systems as well as gravity flow applications. In addition to outstanding pathogen performance, products are also available with special

functionalities such as chlorine removal, heat-sealing and antimicrobial treatment for preventing bacteria build-up. The removal of selected trace metals in a given pH ranges is also possible.

Disruptor can compete as a standalone alternative to polymeric membranes or be used in combination with other water purification technologies and is also easy to convert and be made into virtually any size filter cartridge.

The media now can efficiently remove a wider range of harmful contaminants from water, making it safe to consume, and modified grades offer very high flux rates at lower pressure drops compared to similar biological removal materials.

Compared to ultrafiltration hollow fibers, Disruptor does not block easily, and the filter remains odorless even if not used for several days.

FILTECH 2024 is expected to continue the momentum, slated for November 1214, once again in Cologne, Germany.

p The Heraeus Precious Metals booth stirred discussion on AGXX.

By Bob McIlvaine President

The McIlvaine Company

Bob McIlvaine is the president of The McIlvaine Company, which is helping filter suppliers understand the true cost of their products and the impact on the Serviceable Obtainable Market. He can be reached at rmcilvaine@ mcilvainecompany.com or +1 847.226.2391.

The Benefits of Analyzing Each Filter Niche Opportunity

There are more than one million niches in the filtration market. There are many types of filters for water, liquids, air, and gases to remove contaminants or to create a product. Particulate removal requirements may range from 0.1 to 200 microns. Purification of flue gas to remove sulfur gases is measured in tons per day whereas just a few parts per billion can cause noxious odors.

Mobile vehicles and equipment represent a big market. There are hundreds of industrial niches. Each has multiple processes and unique filtration needs. Residential and commercial applications are numerous. Suppliers offer systems, filtration equipment, components, filter media, and fibers.

Each niche should be analyzed, and the best aggregation selected.

The value of analyzing each niche is undeniable. But no one has attempted it because of the billions of facts and factors which need to be organized. However, many of the facts and factors shaping one niche are shared by many other niches. So, an organized approach provides economy of scale.

The level of needed detail is typical of cost accounting. The detailed approach can be used to gather competitor market share information including tracking acquisitions and exhibitor activity. The exhibition investment of each player in each industrial market in each region not only reveals

present but future activity. If a company suddenly invests a larger percentage of exhibition dollars in Asia or in the pharmaceutical industry it is a good indicator of the strategy.

Continuous analysis of more than five parameters is needed to identify opportunity changes. General economic changes are reflected in geographic and industry adjustments. They reflect the total market whereas acquisitions and exhibitions along with other data determine changes in present and future market share.

An example of the need for a large number of niche analyses is gas turbine intake filters. There are a range of designs for pre-filtration and final filtration. The optimum selection varies with the climate and turbine type. So, forecasts are based on thousands of facts and factors which need to be constantly reviewed.

The future markets are dependent on gas availability, greenhouse gas regulations, Russian aggression, Chinese policy and other factors which are continuing to change.

Filter media efficiency requirements are a function of the application, turbine type, and ambient contaminants. The requirements for FPSOs are different from other environments. They are also a function of media life, turbine life, maintenance, water costs and other factors.

Category Facts Factors

Media Glass, nanofiber, membranes, nonwovens

Efficiency, maintenance, cost

Filters Pre filters, static, pulsed Leakage, pressure drop, maintenance

Turbines Newer designs

Need for better filtration

Conditions Desert, floating, artic, urban Impact on filter selection

Operations Base load or peak Filter impacts

Influences cost such as pressure drop or cost for travel to an oil rig Opportunity Change

Analyses of split by media efficiency address the following:

It is necessary to maintain a current acquisition database. Major changes in the filtration market took place recently with the purchase of Evoqua by Xylem.

Below are examples of acquisitions in the last few years involving cartridges.

In the case of Donaldson, there has been expansion of the off-road dominance to move into tangential flow filters in biotechnology. Along with the filter acquisitions, Donaldson became a supplier of biopharma process equipment.

Exhibitions (right table): There are many exhibitions where filters are displayed. It is important to analyze this activity. It reveals the strategy of competitors regarding products, applications and locations. Here is an analysis of filtration-related stands at the November 2023 International Filtration Conference.

The program includes new technologies for zero liquid discharge and reuse of produced water, which add new facts and factors, which will change the niche market forecast.

An organized approach to identify each niche opportunity with costs minimized by scale will allow filter companies to achieve both greater share and EBITDA.

Mobile vehicles and equipment represent a big market. There are hundreds of industrial niches. Each has multiple processes and unique filtration needs. Residential and commercial applications are

Closing the Purchase Agreement at the Bottom of the Ninth Inning!

when either Seller/Buyer decide to get the deal closed and avoid many hours of additional agony.

By Len LaPorta Managing Director, Wiley Bros.-Aintree Capital, LLC

Len LaPorta is a managing director of Investment Banking at Wiley Bros.-Aintree Capital, LLC – a 75-year-old firm, located in Nashville, TN, focused on investment brokerage and underwriting municipal bonds for utility districts in the state of Tennessee. Len brings to the Firm experience in crossborder M&A transactions between USA and Europe, advises business owners on sell-side and buy-side transactions, capital advisory, and valuations. Len is a graduate of the U.S. Naval Academy with MBA from Boston College and a veteran of the U.S. Navy. He is also a member of INDA’s non-woven Technical Advisory Board. llaporta@wileybros.com or (615) 782-4107.

Interpretation of standard language in the Purchase Agreement leads to many differences between Seller and Buyer. M&A advisors, various legal counsels and accounting professionals have experience in these matters and are able to provide their perspectives during the negotiations. Some items are like “flipping a coin” as to which side is correct.

In many cases, some contentious items resolve

Manufacturing activity continued to decline in New York State, according to the March survey. The general business conditions index fell nineteen points to -24.6, continuing the see-saw pattern of ups and downs within negative territory seen in recent months.

Twenty percent of respondents reported that conditions had improved over the month, and forty-five percent reported that conditions had worsened. The new orders index fell fourteen points to -21.7, indicating that orders declined substantially, and the shipments index fell fourteen points to -13.4, pointing to a decline in shipments.

Examples of negotiating points and possible resolution during the process of developing the Purchase Agreement:

Section Seller’s Position Buyer’s Response Proposed Resolution

Article 1 “Adjusted EBITDA”

Definition of Adj. EBITDA to include any expenses outside of the ordinary course of business that are reasonable and necessary in Buyer’s reasonable business judgement, with the consent of the Owner.

Buyer has rejected the Owner consent requirement. Buyer has added expense arising out of or relating to unexpected events that have or may cause damage to the assets, operations, or financial performance of the business.

See Buyer response Buyer has added the obligation for Seller (and its Affiliates) to pay and satisfy, in due course, all Excluded Liabilities.

Restore. Substitute president of company for Owner to provide consent.

Section 2 Earnout Payment Security

Section 6 Removal of Personal Property

In the event that payment of the Earnout is delayed beyond a certain date, any amounts owed to Seller will accrue interest at a rate of 18%.

Owner will have 3 months following Closing to remove all personal items from the office, at Buyer’s expense and with Buyer’s cooperation.

Rejected

Add clarification that no personal obligations will be imposed on Owner to enforce this provision. Do not want to convert entity obligations to personal obligations.

Restore. Seller should not be forced to subsidize Buyer’s inability to pay the deferred purchase price when due.

Section 7 Conditions to Obligations of Seller

Removal period reduced to 2 months. All expenses to be borne by Owner without cooperations by Buyer. Owner is restricted from interrupting normal business operations during that period and will be confined to his office (and no other areas of the premises).

Buyer to deliver a certificate of the Manager of Buyer attaching the authorizing resolutions for the transaction. Rejected

Needlessly antagonistic. Allow until the end of quarter.

This is a standard deliverable. Need consent from parent for issuance too.

Section 9 Governing Law/Forum Ohio Virginia New York

p Empire State Manufacturing Survey (March 2023) Federal Reserve Bank of New York

Bridging the “gap” between Seller and Buyer is one of the biggest challenges to closing a transaction. The stress meter definitely pegs to the far right.

The monthly survey of manufacturers in New York State conducted by the Federal Reserve Bank of New York. https://www.newyorkfed.org/survey/empire/empiresurvey_overview Note: Survey responses were collected between March 2 and March 9.

The unfilled orders index came in at -6.7, a sign that unfilled orders continued to decline. At -7.6, the delivery times index was negative for a second consecutive month, indicating that delivery times shortened. The inventories index moved down eight points to -1.9, indicating that inventory levels held steady.

Good luck closing your transaction!

This article has been prepared solely for informational purpose. This article does not constitute an offer, or the solicitation of an offer, to buy or sell any securities or other financial product, to participate in any transaction or to provide any investment banking or other services, and should not be deemed to be a commitment or undertaking of any kind on the part of Wiley Bros. –Aintree Capital, LLC (“WBAC”) or any of its affiliates to underwrite, place or purchase securities or to provide any debt or equity financing or to participate in any transaction, or a recommendation to buy or sell any securities, to make any investment or to participate in any transaction or trading strategy. Any views presented in this article are solely those of the author and do not necessarily represent those of WBAC. While the information contained in this commentary is believed to be reliable, no representation or warranty, whether expressed or implied, is made by WBAC, and no liability or responsibility is accepted by WBAC or its affiliates as to the accuracy of the article. Prior to making any investment or participating in any transaction, you should consult, to the extent necessary, your own independent legal, tax, accounting, and other professional advisors to ensure that any transaction or investment is suitable for you in the light of your financial capacity and objectives. This article has not been prepared with a view toward public disclosure under applicable securities laws or otherwise.

By Matt O’Sickey Director of Education & Technical Affairs, INDA

Matt O’Sickey, PhD is Director of Education & Technical Affairs at INDA, Association of the Nonwoven Fabrics Industry. Matt was previously Director of Technology for RKW-North America and Global Director of Market Development for Tredegar Film Products and may be reached at mosickey@inda. org or +1 919 459-3748.

The Benefits of Cabin Air Filtration in Aircraft

As the saying goes, all good things must come to an end, and earlier this spring, over three years into the pandemic, I finally succumbed to the COVID-19 virus. Thankfully it was a mild case, but it did cause friends and family to comment that it was surprising that I had gone three years without experiencing this new right of passage. The reason for their surprise is that, in the course of the last three years, I have spent many days volunteering in vaccination clinics during the early vaccination rollout, have worked in an open office environment during some significant peak periods of outbreak, and logged over 150 domestic and international flights and spent multiple hundreds of hours in airports. It’s the last point, the time in the confined spaces of airplanes, that seemed most risky when considering all the microbes that were dodged. It was in wondering about this that led to the topic of this Tech Talk: Cabin Air Filtration in Aircraft.

regarding COVID-19 transmission methods and looking back to prior pathogen outbreaks of global significance, there is a wealth of peer-reviewed studies for pathogens such as H1N1 and influenza. In analyzing the impact of the 2009 H1N1 outbreak, it was noted, “The large scale spatial diffusion was portrayed clearly as the virus was spreading through air travel. Our estimation validates that a solid relationship between H1N1 and air travel exists, and predictions could be made based on these findings. Also, the epidemic features of this novel H1N1 virus, including the basic reproductive number, the infectiveness duration, are estimated and control strategies are discussed.” In reviewing a sampling of the literature that discusses transmission of influenza on aircraft, a number of themes are common.

As director of education and technical affairs, Matt presents regular training related to nonwovens and filter media from INDA’s headquarters in Cary, NC.

For more information about upcoming training opportunities, visit inda.org/training

Well before the COVID-19 pandemic, air travel had an unsavory reputation amongst travelers for the spread of disease. The Aerospace Medical Association noted, pre-pandemic, that increases in availability of air travel, and especially the increase in international air travel, results in the potential for the spread of illness amongst air travelers. They also recognize that many symptoms that passengers experience during or after air travel are physiological effects due to air travel stresses rather than actual microbial pathogen caused illnesses. These physiological effects are due to differences in aircraft cabin air pressure and humidity. The reduced barometric pressure results in a drop of blood oxygen saturation to levels as low as 90%, a level tolerable to most reasonably healthy air travelers. Air travelers with pre-existing conditions, such as those with coronary, pulmonary, and anemic conditions, may feel this stress more prominently.

Also of concern, is the lower aircraft cabin humidity, that has historically been as low as 10 to 20%. While the cabin humidity has been seeing increases with the advent of less corrodible aircraft materials, passengers will still experience “symptoms” such as dry congested sinuses and mildly dry sore throats. Setting these physiological effects aside, there are concerns about the spread of pathogens.

Setting aside the politicized and polarizing views

The duration of the flight and the proximity to primary infected individuals are two prominent variables. Those travelling within two rows of the primary infected individuals in economy class are at a higher likelihood of being infected during the flight. Interestingly, some studies have shown a much reduced likelihood of transmission for passengers travelling in the first class cabin, generally attributed to lower passenger density or inter-passenger distance and due to less traffic within the smaller first class cabin. While studies note higher transmission likelihood for those passengers in closer proximity and/or having higher duration of exposure, within a given service cabin, the overall likelihood of transmission is also higher for other passengers.

One particularly telling account from 2009 involved an aircraft with 54 passengers who experienced a ground delay of three hours. “Within 72 hours, 72 percent of the passengers became ill with symptoms of cough, fever, fatigue, headache, sore throat and myalgia. One passenger, the apparent Index case, was ill on the airplane, and the clinical attack rate among the others varied with the amount of time spent aboard.” A majority of passengers were diagnosed with H3N2 influenza via either serologic evidence or other tests. Notably, “the airplane ventilation system was inoperative during the delay and this may account for the high attack rate.” This is a clear indication of the importance of aircraft ventilation and filtration systems,

* International Fiber Journal is owned by INDA, Association of the Nonwoven Fabrics Industry (inda.org).

particularly for limiting or preventing disease transmission for those passengers outside of the near proximity zone.

Conde Nast Traveler reported in 2009 the significant adoption of High Efficiency Particulate Air (HEPA)-style filters in aircraft

and noted that complete cabin air exchange was generally occurring 20 times per hour with 99.7% airborne particle removal. By 2022, that number that had risen to 20 to 30 times per hour with filters removing “99.999 percent of airborne particles, bacteria, and viruses.” By 2022, HEPA filters were used on all aircraft, long and short haul, of the four major airlines in the United States. Boeing notes that the systems used in their aircraft have the following features:

• The volume of cabin air is exchanged every two to three minutes

• HEPA filters similar to those used in hospitals capture more than 99.9% of viruses and bacteria

• Cabin air flows primarily from ceiling to floor in a circular pattern and leaves through the floor grilles near the same seat row where it enters Computation fluid dynamics modelling of the particulate airflow in cabins indicates that under normal operating conditions, “80% of the particles were removed from the cabin in 1.3 to 2.6 min, depending on conditions, and 95% of the particles were removed in 2.4 to 4.6 min.”

Further, in a National Geographic review of aircraft safety during the COVID-19 pandemic it is noted that, “The efficiency of these filters, perhaps counterintuitively, increases for even smaller particles. So while the exhaled globs that carry SARS-CoV-2 can be quite small, HEPA filters effectively remove the vast majority from the air.”

HEPA filters are typically pleated, fibrous filters made with glass or polypropylene fibers and operate via a number of mechanisms. First, particulates larger than the pore sizes between fibers are captured on the surface. This mechanism is sometimes referred to as straining. In some cases, a pre-filter is used to capture larger particulates in order to extend the working life of the HEPA filter. Second, small particles that exhibit random motion in the air stream and failing to maintain a consistent laminar flow around fibers, may be removed when impinging on fibers the airstream is flowing around. This is known as a diffusion effect. Third, larger particles that are smaller than the pore size may experience inertial effects as the air stream bends around fibers. In these cases, the particle continues straight, while the air is turning to move around a fiber resulting in the particle embedding on the impeding fiber.

Key fiber variables include the density of fiber coverage and fiber diameter that will impact the size of the pore openings in the

References:

1. Aerospace Medical Association, Medical Guidelines Task Force, “Medical Guidelines for Airline Travel, 2nd ed.”, Aviation, Space, and Environmental Medicine, Vol. 74, No. 5, Section II, May 2003.

2. CHANG ChaoYi CAO ChunXiang, WANG Qiao, CHEN Yu CAO ZhiDong , ZHANG Hao , DONG Lei, ZHAO Jian, XU Min, GAO MengXu, ZHONG ShaoBo , HE QiSheng, WANG JinFeng, LI XiaoWen “The novel H1N1 Influenza A global airline transmission and early warning without travel containments”, Chinese Science Bulletin, September 2010 Vol.55 No.26: 3030–3036.

3. Moser, Michael , Bender, Thomas, Margolis, Harold, Noble, Gary, Kendal, Alan, Ritter, Donald, “An Outbreak Of Influenza Aboard A Commerical Airliner”, American Journal of Epidemiology, Volume 110, Issue 1, July 1979, Pages 1–6, https://doi.org/10.1093/ oxfordjournals.aje.a112781.

4. Wagner, B.G., Coburn, B.J. & Blower, S. Calculating the potential for within-flight transmission of influenza A (H1N1). BMC Med 7, 81 (2009). https://doi.org/10.1186/1741-70157-81

5. Leitmeyer, Katrin, Adlhoch, Cornelia, “Influenza Transmission on Aircraft A Systematic Literature Review”, Epidemiology, Volume 27, Number 5, September 2016.

6. Peterson, Barbara, “The Air Up There”, Conde Nast Traveler, Dec 15, 2009, https://www.

filter surface and throughout the filter. Having higher numbers of lower diameter fibers will result in a reduction in the open path space between fibers and increase likelihood of particles impinging on fibers. The distribution of fibers will impact the tortuosity of the filter and creating opportunities for impingement upon fiber surfaces. Fiber diameter within the filter will influence potential for inertial impingement. Considering the filter itself design variables include height and pitch of pleats as well as the radius of curvature at the point of pleat folding.

The overall efficiency is a combination of these three mechanisms. H13 and H14 HEPA filters will filter at least 99.95% and 99.995% of particles at the most penetrating particle size for a given filter design.

Before closing, there is a final point to make – in some of the articles discussing the efficacy of the aircraft cabin air filtration and overall safety of air travel during the COVID-19 pandemic period, it has been noted that HEPA filters ability to filter viral and microbial particles increases as the filters become dirty. As noted in prior Tech Talk columns, while this is technically true, this is not advisable as the overall performance of the air filtration system will suffer and there may be a reduction in the functional life of the system.

There is strong evidence suggesting that without a well designed and functioning aircraft cabin filtration system, the risk of disease transmission increases dramatically. Further, it is also seen that HEPA filters, when used in such systems, provide significant protection. Considering the fiber and nonwoven design factors that influence filtration efficiency, it is clear that quality control to maintain consistent and on target filter media construction is of paramount importance.

cntraveler.com/stories/2009-12-15/the-air-up-there.

7. Magee, William, “ How Clean Is the Air on Planes?“ Conde Nast Traveler, Sep, 20, 2022, https://www.cntraveler.com/story/how-clean-and-safe-is-a-planes-cabin-air.

8. Boeing, “Travel Confidently with Boeing”, https://www.boeing.com/confident-travel/cabinair.html, Accessed 2023-04-16.

9. Zee, M., Davis, A.C., Clark, A.D. et al. Computational fluid dynamics modeling of cough transport in an aircraft cabin. Sci Rep 11, 23329 (2021). https://doi.org/10.1038/ s41598-021-02663-8

10. Lufthansa, “Meet the Expert”, https://twitter.com/Lufthansa_USA/ status/1263786685239705600?s=20

11. Read, Johanna, “How clean is the air on planes?”, National Geographic, Aug 28, 2020, https://www.nationalgeographic.com/travel/article/how-clean-is-the-air-on-yourairplane-coronavirus-cvd Accessed 2023-04-09.

12. CIBSE Journal, “Understanding HEPA Filters”, https://www.cibsejournal.com/technical/ understanding-hepa-filters/, Posted August 2020, Accessed 2023-04-13.

13. Wikipedia, “HEPA”, https://en.wikipedia.org/wiki/File:HEPA_Filter_diagram_en.svg, accessed 2023-04-13.

By 2022, HEPA filters were used on all aircraft, long and short haul, of the four major airlines in the United States.

Sulzer to Establish New Clean Technology R&D Center in Singapore

Sulzer Chemtech has signed an agreement with JTC Corporation, the master planner and developer of Singapore’s industrial infrastructure, to build and operate a new research center for its separation technology solutions.

The new facility will be located at the Jurong Innovation District’s CleanTech Park, Singapore’s first eco-business park specifically designed to support clean and sustainable manufacturing and urban solutions. Sulzer will focus its research activities on chemical separation processes for circular operations such as polymer recycling and bio-based fuel and polymer production.

Executive Chairwoman of Sulzer Suzanne Thoma said, “This investment in a new research and development center for Asia Pacific is a significant expansion to Sulzer’s global footprint and supports our strategic goals of progress, and the development of sustainable solutions. It also shows our commitment to innovation through continuous, significant spending in R&D.”

Uwe Boltersdorf, Sulzer Chemtech division president, added, “Several Sulzer Chemtech separation technologies are enabling the transition towards more eco-conscious, circular operations. With our clean technology R&D center in Singapore we continue to anticipate and address market needs and enable sustainable manufacturing in the region.” www.sulzer.com

Sandra Martinez Joins Hollingsworth & Vose

Hollingsworth & Vose announced that Sandra Martinez will be the company’s new Vice President & Chief People Officer on April 18. Martinez brings a strong blend of human resource experience from her extensive 20-year career.

“At H&V, our people are our most important resource, and Sandra was the ideal person to lead this essential facet of our organization,” said Josh Ayer, CEO of H&V. “We selected Sandra due to her business acumen and experience working with a global workforce in key markets such as the Americas, APAC and Europe.”

Prior to joining H&V, Martinez served as the head of human resources for the industrial segment of Barnes Group, a global industrial and aerospace manufacturing company. She has a keen understanding of the manufacturing industry, as she has worked in this sector since 2015. Before her shift to manufacturing, Martinez served as vice president of human resources and compensation and benefits at Univision, the world’s leading Spanish-language media company. She also spent a significant portion of her career at General Electric, where she served for many years in both Europe and the United States.

Within her roles, Martinez has extensively worked across DEI, organizational development, talent management and HR operations. She spearheaded multiple employee engagement campaigns and has addressed employee concerns through innovative solutions. Martinez also served as a member of the Diversity and Inclusion Council for the Manufacturers Alliance. www.hollingsworth-vose.com

NX Filtration Partners with GreenTech for Advanced Water Treatment Applications in China

NX Filtration, the global provider of breakthrough direct nanofiltration (dNF) membrane technology for pure and affordable water, was selected by GreenTech Environmental, a leading publicly listed company in advanced water treatment and wastewater recycling in China, to supply its dNF membranes for large-scale water supply projects in China.

The commercial agreement follows a pilot program of approximately one year, in which NX Filtration’s dNF technology was tested on the removal of emerging micropollutants from surface waters in China. The new full-scale project developments will use dNF membranes to produce drinking water from micro-polluted surface water and quality reclaimed water from alternative water sources, which are increasingly important sources for water production across China.

In anticipation of additional large-scale drinking water projects in China, GreenTech and NX Filtration also concluded a partnership agreement that forms the basis for further expansion across China. In this context, Greentech has started the development of standard pre-engineered modular systems, each with a capacity of 10,000 m3 per day, based on NX Filtration’s dNF technology. These standard building blocks will enable fast delivery of future large-scale projects.

www.nxfiltration.com

p Front row, from left: Ulric Seah, Senior Technical Consultant, Sulzer Chemtech; Uwe Boltersdorf, Division President, Sulzer Chemtech; Leow Thiam Seng, Group Director, Industry Cluster Group, JTC; and Lim Junwei, Director, Urban Solutions & Construction Cluster, JTC.

Driven By Design LLC PUBLISHER advertising@inda.media

+1 239.225.6137

Sabine Dussey GERMANY, FRANCE, AUSTRIA, SWITZERLAND, SCANDANAVIA, BENELUX sabine.dussey@dussey.de +49 2129 5900910

Joan Oakley BUYER’S GUIDE joakley@inda.media +1 248.347.3486

Ferruccio Silvera & Filippo Silvera ITALY & SPAIN info@silvera.it +39 02.284.6716

Frank Strazzulla UNITED STATES +1 949 375 2902 franks@tmsmedia.net

Zhang Xiaohua CHINA ifj_china@126.com +86 13522898423