Abstract: A two-stage water treatment process. In a first stage, an incoming stream of water is processed to remove impurities and produce an outgoing stream of water usable for a first purpose and a waste stream of water not suitable for the first purpose. In a second stage, the waste stream of water is processed to remove hardness and alkalinity and produce a second outgoing stream of water suitable for a second purpose. In an exemplary embodiment, the first stage is a forward osmosis or nanofiltration process, and the first purpose includes production of potable water. The second stage includes the use of a weak acid cation resin system.

Abstract: A high salinity water purification system and process, including a forward osmosis system and a reverse osmosis or nanofiltration system. A concentrated brine of a zinc or iron complex combined with a salt or acid draws pure water across the FO membrane from the influent water. The diluted brine is pumped through a vessel holding an anionic adsorption media to remove the zinc or iron complex and the resultant brine is passed through the RO or nanofiltration system to obtain purified water and a concentrated brine stream. The adsorption media is regenerated by a rinse cycle using fresh water or water from the RO system, removing the zinc or iron complex adhered to the media. The resultant brine is stored and mixed with the output of the RO system.