ADVANCED CONCEPT OF LARGE SEAWATER DESALINATION SYSTEMS FOR ISRAEL

It is generally accepted that Israel and its neighboring countries wil l be, in the next decade, dependent on large seawater desalination pla nts. The preferred technology will, most probably, be SWRO. In this te chnology, a major design problem is the inferior physical, chemical an d microbiological seawater quality, especially on the Eastern Mediterr anean shore. Recent developments in the field of water treatment, hold ing a promising potential to facilitate desalination of low quality ra w water, and to reduce the cost of desalination, are the new technolog ies of membrane processes such as micro- and ultrafiltration. These ne w backwashable capillary technologies, recently commercially introduce d, can dramatically improve the quality of surface seawater. This is e specially important if cooling water from existing power-stations is u sed as feedwater for SWRO plants. This option enables shortening the t ime period needed for construction of large desalination plants and re ducing the cost, in comparison with conventional design options. Compa rative design options of a 150,000 m(3)/d SWRO plants, recently invest igated by Mekorot, are presented. The preferred option, based on UF tr eated cooling water fr om power-station, indicates the lowest desalina ted water cost, within the range of US$0.50/m(3).