The present invention is directed to a method and apparatus for desalinating seawater utilizing a two stage seawater desalination system, a first stage including at least one high performance nanofiltration membrane to receive seawater feed pressurized by a first stage pump sufficiently and to produce...http://www.google.com/patents/US7144511?utm_source=gb-gplus-sharePatent US7144511 - Two stage nanofiltration seawater desalination system
