Desalination costs

Discharge to surface water is the most economical form of concentrate management for seawater desalination plants, regardless of the discharge volume. Due to the availability of ocean discharge for seawater desalination plants, the cost of disposal tends to be less costly than for inland desalination. Costs include pumps and pipes. 

Voutchkov, N. Seawater desalination costs cut through power plant co-location. Filtr. Sep. 41(7), 24-26 (2004)... 

The industry is extremely competitive, with the manufacturers producing similar products and competing mostly on price. Many incremental improvements have been made to membrane and module performance over the past 20 years, resulting in steadily decreasing water desalination costs in inflation-adjusted dollars. Some performance values taken from a paper by Furukawa are shown in Table 5.5. Since 1980, just after the introduction of the first interfacial composite membranes, the cost of spiral-wound membrane modules on a per square meter basis has decreased seven-fold. At the same time the water flux has doubled, and the salt permeability has decreased seven-fold. Taking these improvements into account, today s membranes are almost 100 times better than those of the 1980s. This type of incremental improvement is likely to continue for some time. 

The reverse-osmosis membrane process is considered universally as the most promising technology for brackish and seawater desalination [18]. Potential directions for reducing desalination costs may be deduced by analyzing the cost of the components. 

Compliance with proper operational procedures and following a careful maintenance program can also reduce desalination costs by minimizing the replacement of damaged membranes, reducing the use of cleaning chemicals, and reducing the... 

The main components of RO desalination costs are energy cost and equipment investment. Itemizing the equipment in use, membranes, pressure vessels, pumps,... 

Wilf, M. (2004) Fundamentals of RO-NF Technology. Proceedings of the International Conference on Desalination Costing, Limassol, Cyprus. 

Johnson, W.T., Phelps, R.W. and Beatson, P.J. (Oct. 1997) Wastewater reuse using membranes. IDA World Congress on Desalination and Water Science, Madrid. Adham, S., Kumar, M. and Pearce, W.H. (2004) Development of a model for brackish and reclaimed water membrane desalination costs. Proceedings of the International Conference on Desalination Costing, Limassol, Cyprus. 

Moreover, the sale of salt crystals grown in highly concentrated brines (in particular MgS04-7 H20), might potentially reduce the overall desalination cost, thus confirming the potential interest for the proposed approach. 

Fig. 15 Water desalination costs as a function of the feed solution concentration for...

FIGURE 26.1 Water desalination costs as a function of salt concentration. (From IAEA Technical Reports Series No. 431, Application of membrane technologies for liquid radioactive waste processing, 2005, pp. 1-145. http //www.iaea.org/Publications/ index.html (accessed January 16, 2014).)... 

Nikonenko W, Istoshin AG, Zabolotsky VI, Larchet C, Benzaria (1999) Analysis of electrodialysis desalination costs by convective-diffusion model. Desalination, 126, 207-211. 

In summary, the data presented in Table 5.6 provide an overview of general cost estimates of RO modelled systems. In desalination, costs are sometimes difficult to compare... 

Macedonio et al (2007) evaluated the performance of different IMSs for seawater desalination. In Table 7.2 product characteristics of these systems are summarized. The results indicate an increase of water recovery of the RO unit by up to 52% when NF is used as pre-treatment the introduction of the MCr unit is able to increase the plant recovery factor up to 92.8%, much higher than that of a typical thermal system (about 10%).The overall desalination process appears also very attractive from an economic point of view, due to the high quantity and quality of produced crystals. So the sale of salt crystals (in particular MgS04 7H20) might potentially reduce overall desalination costs. 

Figure 3.20 Seawater desalination cost reduction during last 20 years. (Taken from papers in Semiat et al., 2004.)...

Medina, J. A. (2004). 20 years evolution of desalination costs in Spain. In Semiat et al. (Ed.) Proceedings of International Conference on Desalination Costing, Limassol, Cyprus, The Middle East Desalination Research Center, Muscat, Oman. 

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