FAVORITE PAPERS

As you can see, we have followed the pattern of the last Connections and offered the favorite papers identified by five more veterans of our community. Of course, one looks to see if a pattern arises. I am pleased to say that there is none! And that is as it should be. These are individuals whose experiences and needs vary. And besides, de gustibus non est disputandum.

Evolution of Composite Reverse Osmosis Membranes

By John E. Caddotte

J.E. Caddotte, Evolution of composite reverse osmosis membranes in: D.R. Lloyd (Ed.), Material Science of Synthetic Membranes, ACS Sym, Ser. No. 269, American Chemical Society, Washington, D.C., 1985, pages 273-294 https://doi.10.1021/bk-1985-0269.ch012

Nominated by: Dr. Masaru Kurihara Water Treatment Division, Toray Industries, Inc. masaru.kurihara.z9@mail.toray

Caddotte presented an excellent overview on the development of composite reverse osmosis membranes with the emphasis on types that have survived the selection for commercial development and on the chemistry and composition of these membranes in 1985 as well.

In the early 60s, it was shown that Loeb-sourirajan cellulose acetate membrane was asymmetric, having the thin dense layer over a microporous film. Asymmetric membranes resulted from casting a single polymer solution in one step, composite membranes, on the other hand, are formed in two steps, casting of microporous support first, followed by deposition of barrier layer on the surface of this microporous support layer.

Typical commercial examples of asymmetric membranes were cellulose acetate-spiral wound element by U.O.P. and linear fully aromatic polyamide-hollow fiber membrane by Du Pont in the late 60s. Although the early stage of research on the composite membrane using cellulose acetate has started at North Star Research Institute and U.O.P. in the U.S. in the middle of the 60s, the authentic and severe competition of R&D on composite membrane as post asymmetric membranes has been done between the U.S. (North Star Research Institute (Film Tech) and U.O.P.) and Japan (Toray and Teijin).

Since the late 70s, rapid progress has been made in the development of commercial composite membranes. A big and memorable conference was held in Nice, France, 1979 as International Desalination and Environment Association (IDEA). During the conference, four companies from the U.S. and Japan made the presentation on seawater desalination membranes including Du Pont (B-10: linear aromatic polyamide-hollow fiber membrane / asymmetric type), and Film Tech (FT-30: Crosslinked fully aromatic polyamide-spiral wound composite membrane).

FT-30 is prepared by the interfacial polymerization of aromatic diamine and aromatic triacyl halide on the surface of the support film. From Japan, Toyobo presented CTA hollow fiber membrane-asymmetric type and Toray presented PEC-1000 spiral wound composite membrane.

PEC-1000 membrane was prepared by an acid catalyzed in siti poycondensation reaction of 1.3.5.-tris (hydroxyethyl) isocyanuric acid and furfural alcohol on a microporous support.

The main discussion points were the membrane performances and membrane durabilities: 1. Seawater desalination process:

One-stage or two-stage 2. Water recovery: 10 – 20% or 30 – 40% 3. Chemical stability of the membrane against chlorine & dissolved oxygen in seawater 4. Physical stability of the membranes to the temperature of seawater

Toray changed from PEC-1000 composite membrane to UTC-80 composite membrane in the late 80s due to the lack of dissolved oxygen resistibility of PEC-1000. Toray’s UTC-80 composite membrane is prepared by the interfacial polymerization of the aromatic diamine and triamine with aromatic diacyl halide and triacyl halide on the microporous support film.

Before Du Pont (before the merger with Dow) had closed their membrane business on B-10 in 1997, Du Pont also developed the A-15 membrane. The A-15 membrane is the crosslinked aromatic / alicyclic polyamide composite membrane-spiral wound element.

Since 2000, seawater reverse osmosis method has been a major desalination technology against the distillation method in the global market.

As a dominant design of a commercial reverse osmosis membrane became “crosslinked fully aromatic polyamide composite membrane-spiral wound element”, prepared by the interfacial polymerization of aromatic amines and aromatic acyl halides such as FT-30 by Du Pont (formerly Dow Chemical) and UTC-80 by Toray Industries, Inc.

The global market share of crosslinked fully aromatic polyamide composite membrane-spiral wound element is now over 90%.

About the Nominator

Dr. Masaru Kurihara is an advisor at Toray Industries, Inc. and a Senior Scientific Director, “Mega-ton Water System” in Japan Funding Program for the world-leading innovative R&D during FY2009 – FY2013. His research has been focusing on the membrane-based technologies for over 50 years since 1970.

He was the recipient of numerous awards in recognition of his research contributions, including “Lifetime Achievement Award” in 2011” and “Outstanding Professional in Water Reuse and Convention” in 2016 from IDA.

He was elected as IDA Honorary Council Member in 2017 and also assumed his position as a fellow of Chemical Society of Japan in 2009. In 2015, he received “Lifetime Achievement Award” from the Society of Polymer Science, Japan.

The Water that Built Dubai: Ten Years of Desalination History in Jebel Ali

By Emilio Ghiazza and Laura Riccardo

Presented at: IDA World Congress – Atlantis, The Palm – Dubai, UAE November 7-12, 2009

Nominated by: Dr. Emilio Gabbrielli Consultant emilio.gabbrielli@gmail.com

The basic process of desalination of salty water by its evaporation and the subsequent condensation of the vapor could not be simpler. The existence of this natural phenomenon would have been present in people’s mind and experience well before ancient Greeks started mentioning it in written form as a way of desalting seawater in the VI century b.C. One well-known method described is that of collecting condensed vapor on a sponge kept on top of boiling seawater on-board of Greek and Roman ships navigating in the Mediterranean.

The basic simplicity of the process could not be further away from the complexity and technical achievements of modern desalination with evaporative processes. I had the privilege of learning all this by direct experience while designing, commissioning and above all operating MSF plants in Libya in the 70s. I became fascinated by a technology which managed to utilize such a simple basic phenomenon and make it happen explosively and in stages, so that you could produce a quantity of distilled water which is many times the quantity of vapor used to evaporate the seawater in the first place.

This long introduction in order to emphasize the strong impression that this paper dealing with ten years of desalination history in Jebel Ali made on me at the IDA World Congress in Dubai in 2009. I had been less attentive to the latest developments in desalination during the previous 10 years. It was at the congress that it really hit me that in Jebel Ali the size of the last MSF units designed and built had reached MIGD 17.5 (it actually reached 18.3 MIGD during actual operation). Indeed the paper was stating that the industry was already ready to reach MIGD 20. This capacity is 20 times or more than the units I was involved with in Libya.

With the amount of water from a 20 MIGD unit it would be possible to fill an Olympic-size pool in about 40 minutes: this is a lot of water, produced just by one unit! I actually remember Roberto

Borsani telling me in Dubai that the potential to go over MIGD 20, even up to 30, was there, one of the limiting factors being the size of pumps. Still, as the paper explains, the size of pumps had doubled in just 10 years, so why not looking at MIGD 30?

One of the successes of MSF technology is its reliability during long periods of uninterrupted operation, which has been progressively ensured through choice of materials and optimization of choice and use of chemicals, as clearly described in the paper with regards to the Jebel Ali experience. This reliability was achieved at Jebel Ali while also increasing the TBT (top brine temperature) from 105 to 112 deg.

It is somehow ironic that the era of prominence of evaporative processes in seawater desalination, in particular MSF, seems to have definitely gone at the very time when MSF had reached new heights like in Jebel Ali. Still, this is unavoidable as part of technical progress. The know-how on show in Jebel Ali will not be lost and the achievements described in the paper will keep serving the people of Dubai for many more years to come.

About the Nominator

Dr. Emilio Gabbrielli has over 45 years’ experience in water desalination and reuse. After discovering desalination by participating in the design and construction of a solar still in Peru in 1975, he worked with dual purpose plants, mainly in Libya, and pioneered the issue of remineralization. He later plaid a key role in the design and building of zero-discharge schemes for coal-fired power stations in Australia. Between 2003 and 2008 he was the CEO of the Global Water Partnership.

Emilio served as IDA President for the 2015-2017 term, and is a Member of the Honorary Council. He currently operates as an independent consultant.

Research and Development Towards the Increase of MED Units Capacity

By Vincent Baujat, Thierry Bukato

Presenter: Vincent Baujat at IDA World Congress, Bahamas. 2003

Nominated by: Dr. Leon Awerbuch, President & CEO, International Desalination Consultancy Associates (IDCA)

Dr Jim Birkett request to contribute a column in IDA Connections entitled “Favorite Paper" was a difficult task. It forced me to think of hundreds of excellent papers presented at IDA Congresses, Forums and events which contributed to the advancement of desalination and water reuse technology.

As my professional interest was in thermal and hybrid processes, I thought to underscore importance of efforts undertaken by SIDEM and IDE resulting in the Multi-Effect Distillation (MED) technology to reach large scale projects. Particularly because of my personal belief that with solar low temperature renewable energy the multi-effect MED and MD should be able to compete with today SWRO domination.

Finally, I decided to select a paper presented by Vincent Baujat at IDA World Congress in the Bahamas. Until the mid-1990’s, the water production capacities of most MED units ranged from small (0.25MIGD) to mid-size (2 MIGD). Since 1998, the production range of MED units has increased considerably. MED units with rated capacities of 5 MIGD have been in successful operation. The paper reviewed SIDEM R&D efforts that went into the study of operating plants to identify the key process and technological issues that were to be considered in the design of larger MED units. Baujat explains how this analysis was followed by sustained research and development work focusing on the most critical points of system design. This included thermocompressor optimization by means of numeric calculation, optimization and wetting control of the heat transfer tube bundles and development of steam transformers to raise pure steam from the heat reject of power plants.

Having explained how the latest developments in the MED technology result in this process being available for large plants he describes the cost advantage for investors who will make the choice of MED technology for large BOOT projects.

What is amazing is that in January 2007 only four years later Jubail-Marafiq IWPP was awarded being the third largest operating plant in the world a 800,000 m3/day of 27 units X 6.56 MIGD, 8 effects with GOR 9.84 and electric power consumption of 1kWh/ m3, followed in August 2007 by the largest MED-SWRO hybrid at Fujairah 2 130 MIGD plant, MED of 12 units 8.5 MIGD, with 8 effects and GOR of 9.39 and the top performing MED at Az Zour North 107 MIGD 10 x 10.84 MIGD units with the lowest electric power consumption: 0.9 kwh/m3 and low steam consumption: 1 ton of steam generates 11 ton of distilled water. The experience of SIDEM lead to the success of SWCC-Sasakura who have designed, constructed, and tested the world’s largest Multi-Effect Distillation (MED-TVC) unit producing 91,200 cubic meters per day. The Shoaiba 2 new 10 effect desalination unit is designed with 20 MIGD capacity and Performance ratio 14.6 kg-distillate /2,326KJ in December 2018.

I hope that based on the above experience we can soon demonstrate straight MED with low electrical consumption of 1.3-1.5 kWh/m3 operating 24/7 driven by low temperature renewable thermal energy resources.

About the Nominator

Leon Awerbuch involvement in desalination extends for more than 50 years. He joined Bechtel Group in 1972 in R&D followed by increased responsibilities for power and water programs as International Bechtel Co. Ltd Vice President and Senior Regional Representative for the Middle East. Mr. Awerbuch co-author IDA Constitution was Chairman of six IDA World Congresses. He was Director of the IDA for 44 years, has been a Chairman of IDA’s Technical Programs for 26 years, and first Dean of IDA Desalination Academy for 7 years. He has organized and chaired over 40 conferences and forums around the world. Mr. Awerbuch was granted 28 patents. He received a Lifetime Achievement Award from IDA, Life Achievement at Power Generation and Water Solutions Middle East, in January 2015. Leon Awerbuch was voted one of Water & Wastewater International’s top 25 industry leaders, and in 2019 awarded 51 Most Impactful Leader in Water and Water Management. He is an IDA Past President, and current Member of the IDA Honorary Council; and Co-Chairman of the IDA Energy and Environment Committee.

Mr. Awerbuch received a master’s degree in Chemical Engineering and Chemistry from Warsaw University of Technology

The Role of Chemicals in this Thirsty Planet

By Edward G Darton

Published in the IDA Proceedings of the Perth Conference 2011 PER11-262.doc

Nominated by: Ms. Ursula Annunziata Senior Adviser to H2O Innovation

Chemicals is a word which automatically engenders concerns about toxicity, legality, and even potential death of the planet. But we are all made of chemicals, and there is a chemical formula for everything in our world. So, I wonder, how did “chemicals” get such bad press?

There are many papers that could have been chosen in this wellnigh impossible task, but I find the one I have selected covers many different aspects of a single topic – and covers my question above. It opens up the subject to a far wider audience than the specific desalination community. Ted Darton, the author, has nearly 50 years’ experience in chemicals and desalination, counting among his many exploits, working at the Shevchenko Nuclear Power Plant (Kazakhstan) at the height of the ‘cold war’ in 1976, and being one of the first Westerners to enter China in 1978 following the cultural revolution. The author is well-known to me, (I was, therefore, somewhat loath to select his paper!) as we have worked together for many years, but I really felt this was a brilliant summation, covering chemicals past, present and future, as well as introducing new concepts which the author was working on at the time of the paper.

The paper starts with the past history of chemistry back to Plato, laying out the discovery of the elements throughout time, and why the author feels that organic carbon-based chemicals – rather than inorganic – have a greater capacity for development in desalination; not just as chemicals themselves, but in material science breakthroughs.

He summarizes the history and parallel development of thermal and membrane desalination very neatly, emphasizing the development of the desalting membrane as a true scientific blend of physics and chemistry, and then recounts the increasingly effective methods of maintaining clean membranes, using anti-scalants and anti-fouling techniques and products. A clean membrane, of course, is key to efficient and low-cost desalination.

Having worked most of my life in the industry, I am aware that cost savings are unsurprisingly one of the main drivers in desalination growth. Ted highlights the research areas for chemicals most likely to push desalting forward – more effective cleaners with shorter cleaning times, longer times between cleans and therefore less downtime, multipurpose formulations, and products less dependent on temperature and PH changes. However, sought-after needs such as “greener” products are often found to be less effective and more expensive; I can corroborate this, as my company spent much time and energy going down this route in the search for more effective, safer, and cheaper products!

One main focus of the paper for me was the introduction of the concept of “invisible fouling” whereby as soon as water passes through a membrane, it will start fouling. This concept is explained in detail with cleaning procedures starting before fouling is perceived and/or measured. For me this was a perceptive breakthrough in thinking! And papers are still being presented with this as a new concept.

The paper finishes with some comments on the future of our industry, including the part played by the regulatory bodies, which increases costs and can slow research R&D on new products. A necessary safeguard!? But an expensive one. Work on pandemic vaccinations has definitely shown we can reduce this period.

I have passed this paper on to many new colleagues as it brilliantly portrays the highly significant role that chemicals have in desalination, and how we must adapt our perception and usage of them to improve their impact and development on our world.

About the Nominator

Ursula Annunziata, B.Sc in Chemistry and Zoology, M.Sc in Applied Hydrobiology, London University. Research projects, Unilever and Metal Box, and developed biocides for Legionnaires’ Disease. She has worked in desalination for over 30 years, initially with Houseman, a UK water treatment company, then co-founded Genesys, a technically-focused UK-based company, involved in the operation and optimization of desalination plants around the world, supplying technical support and dedicated chemical products to improve plant performance. Currently acting as senior adviser to H2O Innovation, she has served several terms on the IDA and EDS Boards, and is currently European Desalination Society president.

Rigorous Modeling of the Kinetics of Calcium Carbonate Deposit Formation

By Raviv Segev, David Hasson, and Raphael Semiat

Raviv Segev, David Hasson, and Raphael Semiat, “Rigorous Modeling of the Kinetics of Calcium Carbonate Deposit Formation”, AIChE Journal, Vol. 58, No. 4, 2012, 1222 – 1229.

Nominated by: Dr.-Ing. Heike Glade Engineering Thermodynamics University of Bremen heike.glade@uni-bremen.de

Segev, Hasson and Semiat gave an excellent overview and derivation of a rigorous kinetic model describing calcium carbonate deposit formation on a surface from a supersaturated solution in isothermal turbulent flow through a tube. They provided a detailed model for CaCO3 precipitation combining mass transfer and chemical reaction processes. The rigorous model takes into account multicomponent diffusional transport of all carbonic ionic species. Furthermore, simplified models for high pH and low pH conditions were derived and evaluated.

In the early 60s when multi-stage flash evaporation was almost the only desalination method being applied, David Hasson turned his attention to scaling problems. He focused on deposition and inhibition of scaling species in heat exchangers. Later David Hasson expanded his efforts to study scaling of reverse osmosis membranes together with Raphael Semiat. I am very impressed by the huge number of excellent and inspiring papers by Hasson and Semiat on scaling of heat exchange and membrane surfaces and it was difficult to select my favorite one.

The paper is very valuable for our research on scale formation at the University of Bremen. Furthermore, the paper reminds me of my modeling work on carbon dioxide release from the evaporating brine in multi-stage flash and multiple-effect distillers when I started my research on thermal desalination at the University of Bremen. I struggled with the CO2 kinetics in the carbonate system. Then I took into account that the hydration and dehydration of CO2 in carbonate solutions occur by parallel reaction mechanisms, whereas the reaction steps with CO2 are finite rate reactions in contrast to the instantaneous reaction steps with only proton exchange being involved. Thus, I was not surprised to discover that Segev et al. analyzed the influence of the CO2 hydration reaction on the CaCO3 precipitation rate in a second paper “Rigorous Modeling of the Kinetics of Calcium Carbonate Deposit Formation

– CO2 Effect” published shortly afterwards (AIChE Journal, Vol. 58, No. 7, 2012, 2286-2289).

Both papers are very useful for researchers in the field of scaling, not only in thermal and membrane desalination applications but also in many engineering applications with carbonate systems. Comprehension of deposit formation including the mass transfer and chemical reaction processes is closely linked with scale control efforts. Numerous models have been proposed which are based on highly simplified assumptions. I greatly appreciate the rigorous analysis by Segev et al. and that the multicomponent transport of all ionic species involved in the carbonate system was taken into account. Segev, Hasson and Semiat made a tremendous contribution to the complex topic of scaling.

About the Nominator

Dr. Heike Glade is head of the Research Group Evaporation Technology and Seawater Desalination in the Department of Engineering Thermodynamics at the University of Bremen, Germany. Her research work focuses on thermal and membrane-based desalination processes, brine concentration and recovery of valuables, and scaling on heat transfer and membrane surfaces and its mitigation. Heike Glade was in the board of directors of the German Desalination Society for 12 years. She has been working in the field of desalination for more than 25 years and received several awards over this time.

favorite PAPERS

OK, there is no pattern, but there is plenty of variety. These papers date from the 1960s to very recent times. Some are journal articles, some are presentations from conferences, some are chapters from edited books you name it, we included it.

In the next issue of Connections, we will again tap five veterans for their offerings. Then for the Fall, we will shift gears and ask five young “hot-shots” in our community for the sources of their inspiration. It should be fun!

All the best,

Ms. Jantje Johnson,

IDA Publications Committee, Jantje@ orangeboatsupport.com Dr. Jim Birkett,

at large, westneck@aol.com