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Favorite Papers
Once again we offer you the favorite papers of five veterans of our community. That brings our total to 15, enough to lure us into looking for patterns. But these are hard to spot. The dates ranged from 1966 to 2012, with a bulge in the decade 1980-1989. Sources included regular papers published in journals, papers delivered at conferences, a chapter from an edited book, and even a patent! Only two names (R. S. Silver and H. Lonsdale) appear more than once as author or co-author. Clearly these 15 veterans have read broadly!
So there you have it. For the Fall issue of Connections we will shift gears and offer the favorite papers of five of today’s younger hot-shots. This should be interesting! We do need your help however. To date we have received virtually no feed-back on this little project. Are we really just projecting into a black hole? Should we continue this column? How can we make it better? Any actionable advice would be most welcome.
Sincerely, Jim Birkett
Dr. Jim Birkett, westneck@aol.com
Energy Issues in Desalination Processes
By Raphael Semiat*
Rabin Desalination Laboratory, Grand Water Research Institute, Wolfson Faculty of Chemical Engineering, Technion Israel Institute of Technology, Technion City, Haifa 32000, Israel VOL. 42, NO. 22, 2008 / ENVIRONMENTAL SCIENCE & TECHNOLOGY
Nominated by: Dr. Vasu Veerapaneni
Iam nominating this paper (and some of the references within this paper) because of the importance of energy consumption in desalination processes and the general misconceptions associated with it. It is not uncommon to read about a researcher’s press brief release a new highly permeable membrane has been developed and it can reduce the energy consumption of seawater desalination by more than 50%.
In this paper, the author first discusses the work required to separate salt from water based on thermodynamics and using van’t Hoff’s equation . Based on this evaluation, the author shows that the minimum energy required for desalination, by any method, is around 1.09 kWh/m3 at 50% recovery for a saline solution with 3.5% salt content. Then, the authors discusses the energy required for currently available technologies -specifically membrane based (reverse osmosis) and thermal processes (multi stage and multiple effect). Most publications present energy required for RO plants as electrical energy and those required for thermal plants as steam, often making a direct comparison difficult. This is perhaps one of the few papers that discusses the electrical energy required for pumping water in thermal plants (which is considerable; for example, up to 2 kWh/m3 for MED), and the penalty for loss of energy production, as some thermal energy is used for water production.
The author then discusses some of the “newer” technologies from energy consumption view point.
The author discusses the inherent inefficiency of the humidification/dehumidification and why the energy requirement is more than 800 kWh/m3. And another primary drawback is the extremely large footprint, primarily due to the fact that the heat transfer coefficient of the condensing vapor from air is much lower than for pure water.
The author discusses forward osmosis and why its energy consumption (both
theoretical and actual) will be higher compared to what was being considered at that time for the draw solution in the process.
The author also discusses membrane distillation, which again depends on evaporation that requires 650 kWh/m3 and why energy reuse must be extremely high to lower the energy consumption. The lower heat transfer coefficient also results in larger footprint.
Finally, the author presents a table that shows 1 to 2 kg of water can be produced from 1 kg of various fuels and how this is much less than other energy suages. For example, the energy consumed to produce 1m3 of water from seawater can drive a car only 2 to 10 km or operate the air conditioner in a small room for 1.4 hours. Calculated differently, the energy required to produce water for a typical family is 3.2% of the total energy required for that family. This is a perspective that I have not seen before.
1| J.H. van't Hoff, "The Role of Osmotic Pressure in the Analogy between Solutions and Gases", Zeitschrift fur physikalische Chemie, vol 1, pp. 481-508 (1887)
About the Nominator
Vasu Veerapaneni has a B.S from Kakatiya University, India, M.S and Ph.D. from Rice University, Houston, Texas, USA. He has more than 30 years’ experience in water industry. He is currently Global Practice Technology Leader for Black & Veatch in advanced water treatment, including reuse, desalination and concentrate management. He has worked previously at Lawrence Berkeley National Laboratory, CEREGE at Aix en Provence, and as private consultant. He is a licensed professional engineer in the USA.
For Want of a Nail
By Silver, R. S
Desalination, 1979, 31, 39, 44. https://doi.org/10.1016/S0011-9164(00)88500-8
Nominated by: Eng. Kevin Price
It is not often that the clarity of someone’s writing keeps coming back to haunt you throughout your career. Professor Bob Silver wrote “For Want of a Nail” in 1979. Whenever I refresh my thinking, I pull it out (along with IDA’s “Desalination at a Glance”). Why do I keep coming back? Have you ever answered someone’s desalination question with, “it depends…” followed by lots of words?
Professor Silver was a Scotsman proud of his language and a prolific writer to the newspapers, as well as a successful poet and playwright. He also had significant industrial experience culminating in his appointment to the James Watt Chair of Mechanical Engineering and Thermodynamics at Glasgow University. He has been credited as the father of the modern desalination industry for his practical application and theoretical explanation of MSF, significantly improving energy efficiency and process size.
The small things in desalination can be reflected in a 13th century proverb: For want of a nail the shoe was lost; For want of a shoe the horse was lost; For want of a horse the battle was lost; For the failure of the battle the kingdom was lost---All for the want of a horse-shoe nail.
Desalination is defined by the small things, which requires a surprising amount of interdisciplinary work (including finance and politics). “One might consider the distillation process would be dominated by the physics and engineering of heat and mass transfer arrangements, it has not in practice worked out like that at all.” All that knowledge is useless if scale forms. It was up to the chemists, dealing with only 0.1% of the materials in the process. “It was burnt in on the souls of those of us in a previous generation who had to hammer and chisel off grotesque chunks of scale from submerged tubes.” While his work underlaid the first generation of desalination technology, he foreshadowed what was to come. “I say this is salutary for the future also because I think it is quite certain that the chemical preparation of seawater
[or other impaired sources] for any method of desalination, including membrane processes, will continue to be a demanding feature.” He also pointed out that thermodynamically “…whatever irreversibilities do occur have a very great effect on the result. This is true not only in distillation but runs through the whole desalination field.”
Ultimately, “the production of fresh water from sea water or other contaminated water when seen against all the vast and varied industrial activity of the modern world may seem a small thing. But unless it is provided it could prove to be the nail for lack of which the whole battle of civilization might be lost, even if we solve the energy supply situation.”
Please take a look at the full paper. I’ve just scratched the surface of the importance of the small things in desalination.
About the Nominator
Kevin Price started his career in the early 1980’s studying ultrafiltration pretreatment for the world’s largest reverse osmosis membrane desalination facility in Yuma, AZ. He spent a 30-year career with the U.S. Bureau of Reclamation as a researcher, later managing water treatment engineering and research, and retiring as the coordinator of the Advanced Water Treatment Research Program. He has been a strong advocate for research and innovation including service on the boards of the IDA and AMTA, on the WateReuse Research Foundation’s Research Advisory Committee, on NWRI’s Research Advisory Board, on the steering committee for the WHO Guidance Document on Desalination for a Safe Water Supply, and working with European, Middle Eastern, North African, and Asian countries. He is currently the Senior S&T Advisor for the Middle East Desalination Research Center and sits on the Industrial Advisory Board for the National Alliance for Water Innovation.
By Joanne Daugherty, Kevin Alexander, Don Cutler, Mehul Patel and Shivaji Deshmukh
Daugherty, J., et al. "Applying advanced membrane technology for Orange County’s water reuse treatment facilities." Proceedings of the AWWA Membrane Technology Conference. 2005.
Nominated by: Dr. Craig Bartels
I
have nominated this article due to the historic impact of the development, demonstration, and implementation of an advanced treatment process to reclaim municipal wastewater for indirect potable reuse (IPR). Many articles were published by the team at the Orange County Water District (OCWD), starting with work in the mid 1970’s at Water Factory 21. The original concept of this plant was to make 5 million gallons per day (mgd, or 18,900 m3/d) of RO water and blend with 10 mgd of other reclaimed wastewater to inject into the local aquifer to minimize seawater intrusion. At that time, the treatment scheme was much different from that of today’s wastewater treatment processes. The original plant used lime clarification followed by multi-media filters prior to the RO treatment. Although, this scheme was serviceable, the RO membranes suffered heavy fouling and relatively short life.
This treatment scheme would ultimately be replaced by a micro/ultrafiltration (MF/UF) pretreatment and ultra-low-pressure RO membranes, which is the normal process used worldwide today. This paper by Daugherty et al. documents the development work that was done by the team at Orange County and its various vendors and consultants that ultimately showed that secondary wastewater could be treated by a simple MF/UF process followed by RO, ultraviolet (UV) light and peroxide addition for IPR. This Advanced Water Purification Facility (AWPF) would be the heart of the Ground Water Replenishment (GWR) plant at the same site in Orange County. The high quality water would be injected into the underground aquifer for IPR. I remember visiting this demonstration plant early in my career and was so impressed that they could treat such a difficult and variable feedwater to produce high quality product water with such consistent performance. Still, it was difficult to imagine this 5 mgd plant turning into a 70 mgd (265,000 m3/d) plant and eventually expanding to the final 130 mgd (492,000 m3/d). Neither could I imagine how this technology would spread to other wastewater
plants in the USA and eventually to Singapore, Australia and many other countries.
This paper provided detailed design information for the MF and the RO systems. The Phase 1 plant utilized the Memcor polypropylene 0.2 µm submerged MF membrane, which produced a filtrate with SDI less than 3; this was a huge improvement for the RO feedwater. The MF was designed to produce 87.5 mgd (331 m3/d) of filtered water and operated at 19.3 gfd (32.7 lmh). They pilot tested many different UF/MF membranes at the demonstration facility, which was a prerequisite to be considered for the 70 mgd plant. Likewise, they tested many RO membranes at the demonstration facility. Again, only RO membranes that were successfully pilot tested were to be considered for the GWR plant. Three vendors of low-pressure RO membranes were ultimately tested and qualified. The GWR 5 mgd Phase 1 plant operated at set conditions during 2004 to demonstrate that the process was reliable and suitable for the 70 mgd plant. The operation of the plant showed that the dosing of chlorine to form chloramines adequately controlled biofouling of the RO, and the MF membranes produced a low turbidity feedwater which minimized colloidal fouling of the RO. The operation data did show that the RO still fouled and lost 30-50% of the permeability; however, this eventually stabilized for some membranes and did not drop further. This was later attributed to the dissolved organics which adsorb on the RO membrane surface, but do not build up further. The paper presented much detailed information about ion rejections, but also the permeate concentration of many micropollutants, demonstrating feasibility for IPR.
Finally, the 70 mgd plant started to operation in 2007. The first set of RO membranes lasted 7-8 years, exceeding expectations. I had the opportunity to visit this plant shortly after it began operation and had the privilege to drink a glass of water from the product stream. It tasted great!
About the Nominator
Craig Bartels has a BS in Chemistry from Baylor University and a PhD from Northwestern University in Material Science. Since entering industry, he has over 37 years of experience in all facets of membrane technology, both application and development. He has previously held technical and management positions at Texaco Inc, Fluid Systems, and Metropolitan Water District of Southern California. He currently holds the position of VP of Technology at Hydranautics, a Nitto Denko Group Company.
Yuma Desalting Plant Design
By Mr. Ivyl G. Taylor and Mr. Lorentz A. Haugseth
Presented at “First Desalination Congress of the American Continent”, Mexico City, October 24 – 29, 1976.
Nominated by: Mr. Randy Truby
The Yuma Desalting Plant in Yuma Arizona is one of the largest desalination systems of any type ever built. In October of 1976 Mr. Ivyl Taylor of the US Government Bureau of Reclamation (BuRec) presented a rigorous paper describing the evolution of the decision to design and build the plant and the rational followed by BuRec.
This Yuma Desalting plant is a landmark installation, and its significance was clearly described in the paper:
“The total worldwide desalting capacity as of January 1, 1976, is 526 MGD. Of this total 78 MGD was RO (reverse osmosis) and ED (electrodialysis) processes. The Yuma plant, with a production output of 108 MGD will represent a 133% increase in membrane plant desalting and a 20% increase in world desalting production. The largest ED plant is located in Benghazi, Libya, and has a capacity of 5.07 MGD. The largest RO plant is in Japan and has a capacity of 4.65 MGD.” (1)
In the paper Mr. Taylor explained that the BuRec bid documents stated that a minimum segment procured from a single offeror would be 20 MGD. BuRec also indicated they would consider a minimum of two and a maximum of three processes. Lastly a minimum of two and maximum of three manufacturers was deemed reasonable. Just to add some perspective one 20 MGD contract would be four times larger than any RO or ED system ever built at the time.
The driver for building the Yuma Desalting Plant was a treaty signed by U. S. President Nixon and Mexican President Escheverria in 1970 following the recommendations of the Brownell Commission. The treaty required the US to reduce the salt content of the Colorado River before it entered Mexico at Mexicali. The measurement point was the historical water quality of the Colorado River at the Parker Dam in Arizona. BuRec organized the tender and to this day continues to administer the plant.
In early 1974 prospective bidders conducted pilot studies on the Colorado River under the supervision of BuRec. Competing technologies were tested including three spiral RO modules (Fluid Systems, Hydranautics/Desalination, Systems and Envirogenics), three Hollow Fine Fiber (HFF) RO devices (Dowex, Dupont Permeators, and Toyobo), and two electrodialysis designs (ionics and Asahi). The testing was extensive and continued through 1978.
Conventional wisdom believed that no sole bidder would be awarded more than one 20 MGD segment and that at least one spiral wound RO, one HFF RO, and one electrodialysis membrane would be selected.
Mr. Taylor described the overall process to be used to meet the Treaty obligation and the years of testing at the site that BuRec was continuing to operate. The costs and problems anticipated were also described in detail. Two complicated issues required foresight and ingenuity to resolve:
First the concentrate from the membrane desalination system would be in excess of 10MGD and over 20,000 mg/L TDS. Discharge of this concentrate required the Governments of Mexico and the USA to create a concrete lined drainage canal extending from the US side of the border near Yuma through Mexico to the Sea of Cortez. Mr. Taylor described this drainage canal in detail.
Second the energy consumption was significant, and Mr. Taylor provided an exhaustive analysis. The RO membranes in 1976 operated at 400 to 600 psi and thus BuRec included an energy recovery system in a separate building from the main pump room. This energy recovery section was novel at the time and clearly paved the way for the SWRO energy recovery systems that followed.
The Yuma Desalting Plant was finished and commissioned in the 1990’s but was never put into full scale operation. The US Government diverted high salt content water from the Wellton Mohawk discharge canals away from the Colorado River and thus the salinity of the River met the treaty standards. The high salinity Wellton Mohawk drainage was transported to the Sea of Cortez in the drainage canal originally designed to handle the RO concentrate.
The key significance of the Yuma Desalting plant was the implied endorsement by the US Government that mega membrane desalination systems were reliable and could produce the quality water needed in many applications. Mr. Ivyl Taylor’s paper told the global community membrane desalination had arrived. Four plus decades later the reality of that endorsement is evident.
About the Nominator
Randy Truby has been a professional in the water treatment and membrane desalination industry since January 1969 when he joined Reverse Osmosis General Atomic (ROGA) as a Research Assistant. He currently operates R L Truby & Associates providing consulting and mentoring services.
Mr. Truby has been involved in the manufacture of reverse osmosis, nanofiltration, ultrafiltration, and microfiltration membranes and systems for over 50 years.
Mr. Truby is a Past President of the International Desalination Association (1993-1995). He is also a past Vice President of the American Membrane Technology Association (AMTA). Mr. Truby served as Chairman of the Board for the Affordable Desalination Collaboration (ADC). He has been inducted into the Hall of Fame for AMTA, and received the Lifetime Achievement Award from the Maritime Alliance.
Mr. Truby has authored over 65 presentations on membrane desalination, water treatment technology and water market development. He appeared on the PBS television desalination documentary “By the Year 2000” and has been featured in Fast Company Magazine.
The Growth of Membrane Technology
By Lonsdale, H. K,
Journal of Membrane Science, 10, pp 81-181, Elsevier Scientific Publishing, Amsterdam, (1982)
Nominated by: Dr. Jim Birkett
When I first sought a favorite paper, I immediately thought of any of the papers of the late Professor R.S. Silver of Glasgow, the best wordsmith our trade has ever known. But no, however much I might admire them and him, they did not relate directly to my work. I then considered the work of Professor Barnett Dodge of Yale whose papers in the early 1960s outlined and quantified the minimum energy of desalination and which I have frequently quoted. No, not one of those either. But then I thought of desalination history, my long-time love and specialization. The choice was obvious. Harry Lonsdale’s classic paper on the growth of membrane technology won hands down.
Lonsdale’s paper concludes in 1980; its focus is on the rich development period of 1950 to 1980. (He does however include an excellent but brief (4 page) overview of membrane work prior to 1950.)
Lonsdale casts his net wide. Included are not just membranes used in separations but in other applications as well. Specifically, he gives important development in microfiltration (MF). Ultrafiltration (UF), reverse osmosis (RO), dialysis (D), hemodialysis, electrodialysis (ED), and gas separation membranes (including air-splitting and industrial membranes and artificial lungs). In addition he touches upon membranes in ion-specific electrodes and controlled-release medical devices. To me, the best portion is that discussing the emergence of microfiltration after (and because of) World War II and its role in the birth of such firms as Millipore, Gelman, Sartorius, Amicon and many others. I also recommend the section on gas
separation membranes, a field which nearly wooed me away from desalination (but that is another story).
For each topic Lonsdale delivers adequate detail so that the reader can understand the challenges and technical advances to overcome them. Each such “story” stands alone in its own right. However for the reader who wants more there is a 429 entry, 25 page bibliography which is a treasure trove of fascinating detail and supporting references.
I heartedly recommend this paper to anyone considering him (or her) self to be a professional in membrane separations (any technology). It is also, as they say, “a good read”.
About the Nominator
Jim Birkett received his A.B. degree from Bowdoin college and his M.S. and PhD. degrees in physical chemistry, from Yale University. He draws upon his more than 50 years of experience in the study of desalination, advanced water treatment, and membrane separation industries and technologies. He has worked frequently and effectively providing specific industry and technology support in strategic planning exercises, competitive analysis and in evaluating the commercial viability of new processes and process modifications. He is a member of numerous scientific and technical societies and is a past Director and President of the International Desalination Association (IDA). In recent years he has devoted much of his time to researching and publishing the early history of desalination and its applications.
