Water treatment submerged membranes

Largest submerged membrane water treatment plant opens... 

CH2M HILL recently joined the San Diego County Water Authority (SDCMtA) for the opening of the world s largest submerged-membrane water treatment plant. 

Bouhabila, E.H., Ben Aim, R. and Buisson, H. (1998) Microfiltration of activated sludge using submerged membrane with air bubbling (application to wastewater treatment). Conference on Membranes in Drinking and Industrial Water Production, Amsterdam. 

Rosenberger, S., Witzig, R., Manz, W., Szewzyk, U. and Kraume, M. (2002) Performance of a bioreactor with submerged membranes for aerobic treatment of municipal waste water. Water Research, 36, 413—420. 

Some of the largest plants for seawater desalination, wastewater treatment and gas separation are already based on membrane engineering. For example, the Ashkelon Desalination Plant for seawater reverse osmosis (SWRO), in Israel, has been fully operational since December 2005 and produces more than 100 million m3 of desalinated water per year. One of the largest submerged membrane bioreactor unit in the world was recently built in Porto Marghera (Italy) to treat tertiary water. The growth in membrane installations for water treatment in the past decade has resulted in a decreased cost of desalination facilities, with the consequence that the cost of the reclaimed water for membrane plants has also been reduced. 

Davies, W. J., M. S. Le, and C. R. Heath (1998). Intensified activated sludge process with submerged membrane microfiltration. Water Science and Technology Wastewater Industrial Wastewater Treatment, Proc. 199819th Biennial Conf. Int Assoc, on Water Quality. Part 4, June 21-26, Vancouver, Canada, 38, 4-5, 421 28. Elsevier Science Ltd., Exeter, England. 

According to CH2M HILL. SDC A awarded the contract to the company due to it s w ater tr eatment plant concept that uses a submerged-membrane treatment process, which produces high-quality water, is less expensive than conventional processes, and is more environmentally friendly. Tire membrane option allowed for a smaller ibotprint, less concrete, fewer chemicals to store, and fewer solids to dispose of than traditional treamient methods,... 

Tire Zee Weed submerged-membrane technology and equipment for the project was provided by GE Water. Process Technologies. GE s Zee Weed membrane bioreactor systems combine ultiafiltration technology w ith biological treatment for municipal, commercial and industrial wastewater treatment and water reuse applications,... 

Submerged membrane bioreactors are revolutionizing waste water treatment [108]. These units dramatically increase the capacity of waste water treatment ponds while simultaneously producing a higher quality water by using an ultrafiltration membrane to remove treated water from the mixed liquor suspended solids (MLSS) produced by biological treatment. Such process intensification is one of the hallmarks of applications where membrane processes have achieved commercial success (in addition to energy reduction and purification of labile compounds). 

Submerged membrane filtration/bioreactor Japan 1987 Water reclamation/sewage water treatment... 

The application of MF and UF technology in water treatment is still relatively new, as many full-scale plants are less than 10 years old. Consequently, the design of MF and UF systems varies from plant to plant as no single design has proved itself to be the best (see Table 6.2). For example, MF/UF systems may be positioned horizontally or vertically, operate in deadend or cross-filtration mode, the membranes may be immersed/submerged in a feed tank where permeate is sucked (via vacuum) into the inside of the hollow fiber (outside-in filtration) or the membranes may be housed in modules where pressurized feed water is forced through the fiber and permeate is collect on the outside (inside-out filtration). 

Submerged (or immersed) membranes are now commonplace in advanced water and wastewater applications. However, this is a relatively recent development for example, the subject does not rate a mention in Membrane Handbook (Ho and Sirkar, 1992) and only has the briefest mention in Water Treatment Membrane Processes (Mallevialle et al., 1996). This chapter provides an overview of submerged membranes, from basic features to practical aspects and applications. We wiU start with the background to this development. 

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