Reverse osmosis desalination technology

B. Penate, L. Garci a-Rodriguez, Current trends and future prospects in the design of seawater reverse osmosis desalination technology. Desalination 284 (2012) 1-8. 

J. Scott, ed.. Desalination of Seawater by Reverse Osmosis, Pollution Technology Review No. 75, Noyes Data Corp., Park Ridge, N.J., 1981. 

The successful development of asymmetric cellulose acetate membranes by Loeb and Sourirajan in the early sixties, at the University of California, Los Angeles, has been primarily responsible for the rapid development of Reverse Osmosis (RO) technology for brack sh/sea water desalination. Reverse Osmosis approaches a reversible process when the pressure barely exceeds the osmotic pressure and hence the energy costs are quite low. Theenergy requirement to purify one litre of water by RO is only O.OO3 KW as against 0,7 KV required just to supply the vaporisation energy to change the phase of one litre of water from liquid to vapour by evaporation. Thus RO has an inherent capability to convert brackish water to potable water at economic cost and thus contribute effectively to the health and prosperity of all humanity. 

It is the rate of separation rather than the efficiency of salt retention that is the primary practical issue in the development of reverse osmosis desalination. In addition to a variety of other factors, the rate of reverse osmotic flow depends on the excess pressure across the membrane. Therefore the problem of rapid flow is tied into the technology of developing membranes capable of withstanding high pressures. The osmotic pressure of sea water at 25 °C is about 25 atm. This means that no reverse osmosis will occur until the applied pressure exceeds this value. This corresponds to a water column about 840-ft high at this temperature. 

Rosberg, R. (1997). Ultrafiltration (new technology), a viable cost-saving pretreatment for reverse osmosis and nanofiltration—A new approach to reduce costs. Desalination, Int. Symp. Pretreatment of Feedwater for Reverse Osmosis Desalination Plants, March 31-Apr 2,110,1-2,107-114. Elsevier Science B.V., Amsterdam, Netherlands. 

I. Cabas so, E. Klein, and J. K. Smith, Research and Development of NS-1 and Related Poly-stdfone Hollow Fibers for Reverse Osmosis Desalination of Seawater, report prepared for Office or Water Research and Technology, Gulf South Research Institute, July 1975. 

Greenlee LF, Lawler DF, Freeman BD, Marrot B, and Moulin P, Reverse osmosis desalination Water sonrces, technology and today s challenges. Water Research 2009,43,2317-2348. 

L.F. Greenlee, D.W. Lawler, B.D. Freeman, B. Marrot, P. Moulin, Reverse osmosis desalination water sources, technology, and today s challenges, Water Res. 43 (2009) 2317-2348. 

Orofino, T. A. (1970). Development of hollow filament technology for reverse osmosis desalination systems. Report No. 549. U.S. Office Saline Water Res. Develop. Progr. 

Hyperfiltration (Reverse Osmosis) is a form of membrane distillation or desalination (desalting) operating with membrane pore sizes of perhaps 1 to 10 Angstrom units. The various individual RO component technologies have improved tremendously over the last 20 to 25 years, and resistance to fouling and permeate output rates have benefited. Nevertheless, all RO plants remain susceptible to the risk of fouling, and adequate pretreatment and operation is essential to minimize this problem. 

Reverse osmosis membrane process, 27 637 Reverse osmosis membrane cleaning citric acid application, 6 647 Reverse-osmosis membranes, 75 811, 825 development of, 75 797 Reverse osmosis models, 27 638-639 Reverse osmosis permeators, 76 19 Reverse osmosis seawater desalination process, 26 85 Reverse osmosis systems blending in, 26 80-81 brackish and nanofiltration, 26 80-83 Reverse osmosis technology... 

Bonnelye, V., Sanz, M.A., Durand, J.-P., Plasse, L., Gueguen, F., Mazounie, P. Reverse osmosis on open intake seawater pre-treatment strategy. Desalination 167, 191-200 (2004) Committee on Advancing Desalination Technology, National Research Council Desalination A National Perspective. The National Academies Press, Washington, D.C. (2008)... 

All commercial types of processes, with the exception of freezing, namely, distillation, reverse osmosis and electrodialysis, are being applied in the above units with various kinds of distillation processes being used for seawater desalting. Two of them, horizontal tube multieffect distillation and vapor compression units were developed and manufactured locally by the Israel Desalination Engineering Ltd. Recently, two small RO units with a combined capacity of approx. 100 cu. m/day were also used to desalt seawater. The main aim of these units is to test and demonstrate the feasibility of this new technology. 

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