Energy savings desalination

Desalination. Desalination of seawater and brackish water has been and, as of the mid-1990s, is the primary use of RO. Driven by a need for potable water in areas of the world where there is a shortage, this industry has developed. Desalination involves the reduction of the total dissolved soHds (IDS) concentration to less than 200 mg/L. RO offers several advantages over other possible desalination processes such as distillation (qv), evaporation (qv), and electro dialysis. The primary advantage of RO over the traditionally used method of distillation is the energy savings that is afforded by the lack of a phase change in RO. 

Persistent interest in studying the clathrate systems is largely caused by the great diversity of areas of their practical application. They can be used in efficient fine purification of substances, in isomer separation [95,96], in the development of energy-saving water desalination technologies, etc. In recent... 

These features are likely to encourage further development of vacuum or solar evaporation salt recovery operations to work these brines in proximity to the desalination plants. In this way, various salts may be more profitably recovered from these artificially enriched seawaters for reasons similar to the present incentives to use the rich natural brine sources for sodium chloride production (Table 6.3). Similar energy savings should be obtained. 

Tani, Y Energy-saving electrodialyzer for seawater desalination. Tech. 

Brackish Water Desalination Low-pressure membranes were used by Glueckstern et al. (1986) for brackish water desalination. With a feed water of 6000-6500 mg/1, recovery of 65%, and applied pressure of 14 bars (net driving pressure of 7 bars), a salt rejection of 95% was obtained. An energy saving of 33% was achieved. 

One of the most dramatic examples of the energy savings offered by membrane processes is desalination. Initial desalination plants relied exclusively... 

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. 

It is desirable to perform electrodialysis at as high a temperature as possible to save energy, if the membranes and electrodialyzer permit.151 However, when conventional ion exchange membranes are used in high temperature electrodialysis, osmotic water and electro-osmotic water through the membranes increase with increasing temperature. Thus, the amount of water produced decreases in the desalination of saline water and the concentration of the concentrated solution decreases in a concentration processes. On the other hand, a serious problem in electrodialysis is the precipitation of calcium sulfate in the concentrated compartment and the anion exchange membrane. 

In addition to calculating the expenses of a complete process, one can also calculate the economic impact of modifying a process. Consider the precooler we added to the desalinator, shown in Figures 3.24 and 3.29. The precooler saves energy and thus lowers operating cost, but it requires an additional capital cost. Is a precooler justified economically Let s apply mathematical modeling to compare the two options no precooler and precooler. 

Eftihia Tzen (water desalination, desalination with renewable energy sources). Wind Energy Department, Centre for Renewable Energy Sources Saving, Pikermi... 

M.A. Anderson, A.L. Cudero, J. Palma. Capacitive deionization as an electrochemical means of saving energy and delivering clean water. Comparison to present desalination practices WiU it compete Electrochim Acta 55 (2010) 3845-3856. 

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