Water desalination integrated membrane system systems

In this chapter, some important examples of integrated membrane systems will be presented starting from the most well-known application of membrane technology, that is, water desalination. 

An integrated membrane desalination system as a new and innovative technique for contaminant removal from water was investigated by Macedonio and DrioU (2008). 

Furthermore, water scarcity has led to the widespread use of desalination to supplement freshwater resources. While reverse osmosis (RO) membranes are used to desalinate seawater and brackish water, MF/UF can be applied as a pretreatment to RO, in an integrated membrane system (IMS). The level of pretreatment, in terms of turbidity and silt density index (SDI), provided by MF/UF was found to be significantly better and more consistent than conventional pretreatment to RO (e.g., coagulation/sedimentation/filtration) for RO feed water. In recent years, the demand for MF/UF as a pretreatment to RO has grown as the need to augment our... 

Although RO water desalination is today considered as the most cost-effective solution [4], key factors for further improvements in membrane-based desalination systems are enhancement of water-recovery factor, cost reduction, improvement of water quality, new brine-disposal strategies. All these issues can be addressed by an integrated approach. 

Integrated Membrane Processes for Water Desalination 266 Integrated Membrane Process for Wastewater Treatment 271 Integrated Membrane System for Fruit-Juices Industry 274 Integrated Membrane Processes in Chemical Production 276 Conclusions 281 References 281... 

J. C. Kruithof, J. C. Schippers, P. C. Kamp, H. C. Fohner, and J. A. M. H. Hofinan, Integrated multi-objective membrane systems for surface water treatment pretreatment of reverse osmosis by conventional treatment and ultrafiltration. Desalination 117, 37 8 (1998). 

Electrodialysis/electrodialysis reversal (ED/EDR) represents 3% of aU the desalination capacity in the world [48]. It is, however, used mainly for desalinating brackish water. It can achieve 95% water recovery with minimal chemical feed. However, it can only reject ionised matter. Substances such as colloids, silica and boron at pH <8.0 are not removed. A triple-membrane system using UF-EDR-RO has been very effective in producing purified water for power plants [50]. In this integrated system, UF is used for removing suspended solids and macromolecules ... 

In this chapter the possibility of integrating different membrane unit operations in the same industrial cycle or in combination with conventional separation systems is analysed and discussed. Many original solutions in water desalination, agro-food productions and wastewater treatments are reviewed highlighting the advantages achievable in terms of product quality, compactness, rationalization and optimization of productive cycles, reduction of environmental impact and energy saving. 

Key words water desalination, wastewater treatment, integrated membrane systems, agro-food production, gasification, fuel cell, solar membrane reformer. 

This issue is very significant for pretreatment systems for seawater desalination plants with open-ocean intakes. Often the source seawater contains small sharp objects (such as shell particles), which can easily puncture the pretreatment membranes and result in a very quick loss of their integrity, unless the damaging particles are removed upstream of the membrane pretreatment system. As discussed previously, to remove sharp seawater particles that can damage the membranes from the source water, the SWRO plant intake system has to incorporate a microscreening system that can remove particles larger than 120 p,m. 

Couffin, N., Cabassud, C., and Lahoussine-Turcaud, V. (1998). A new process to remove halogenated VOCs for drinking water production Vacuum membrane distillation. Desalination 117, 233. CriscuoU, A., and DrioU, E. (1999). Energetic and exegetic analysis of an integrated membrane desa-Unation system. Desalination 124, 243. 

Since the 1990s, membrane-based separation processes integrated with traditional treatment systems have been successfully deployed in large desalination, wastewater and municipal water treatment plants [1-4]. More than a dozen large seawater RO (SWRO) plants with product water capacities greater than 200,000 m /day have been commissioned in the last decade. 

Ohya, H., Suzuki, T., and Nakao, S. (1996). Proposal and technological breakthrough of an integrated system for the complete usage of sea water. Bull. Soc. Sea Water Sci. Japn. 50(6), 389-395. Redondo, J., Busch, M., and Witte, J. D. (2(X)3). Boron removal from seawater using FILMTEC high rejection SWRO membranes. Desalination 156, 229. 

Due to the low rejection of monovalent salts, osmotic pressures in NF are lower than in RO. Thus, lower pressures need to be applied, and the energy consumption is proportionally lower. RO membranes operable at ultralow pressures have been developed (Semiat, 2000 Matsuura, 2001) that allow the desalination of brackish water at pressures comparable to those applied in NF. These membranes operate at the interface of NF and RO and might be helpful in optimizing the desalination process. Hassan et al. (1998) reported the use of NF in an integrated desalination system NF-SWRO (sea water reverse osmosis) and... 

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