Process for desalination of saline water, especially water, having increased product yield and quality

摘要

A desalination process is disclosed which combining two or more substantially different water treatment processes in a unique manner to desalinate saline water, especially sea water, to produce a high yield of high quality fresh water, including potable water, at an energy consumption equivalent to or less than much less efficient prior art desalination processes. In this process a nanofiltration step is synergistically combined with at least one of sea water reverse osmosis, multistage flash distillation. multieffect distillation of vapor compression distillation to provide an integrated desalination system by which sea water can be efficiently and economically converted to high quality potable water in yields which are at least 70%-80% greater than the yields available from the prior art processes. Typically a process of this invention using the nanofiltration initial step will produce, with respect to sea water feed properties, calcium, magnesium, sulfate and bicarbonate ion content reductions of 63%-94%, pH decreases of about 0.4-0.5 units and total dissolved solids content reductions of 35%-50%.