MULTISTAGE OSMOTICALLY ASSISTED REVERSE OSMOSIS SYSTEM AND METHOD

A purification system is disclosed comprising a first reverse osmosis stage having a high pressure side and alow pressure side and a second reverse osmosis stage having a high pressure side and a low pressure side. The high pressure side of the first reverse osmosis stage outputs a yield stream that is split into a recycle stream and a concentrate stream. The low pressure side) of the first reverse osmosis stage receives the concentrate stream and outputs a purified stream. The high pressure side) of the second reverse osmosis stage receives the purified stream from the first reverse osmosis stage and outputs a reject stream) which is recycled to the high pressure side of the first reverse osmosis stage. The low pressure side of the second reverse osmosis stage outputs a final permeate product. U) 01o (N Co Ul) co (N ' rLO Vf CD (0 c rO U' Uf) (D U UlU) OD cc m 4) LO C