PURIFICATION OF PRODUCED WATER FROM COAL SEAM NATURAL GAS WELLS USING ION EXCHANGE AND REVERSE OSMOSIS

摘要

A method and apparatus are provided for treating produced water to lower thetotal dissolved solids of the water for safe discharge to the environment. Theproduced water is passed through a weak acid cation resin in H+ form (11) toremove cations, and then preferably through a decarbonator (13), to provide afirst discharge stream (17). The cation loaded resin (11) is then regeneratedusing a dilute acid solution (18) that is preferably diluted with producedwater. The resultant acid regenerated waste stream is discharged to a deepwell (20). The acid regenerated resin is then rinsed, preferably with producedwater (21), to remove residual salts and form a salt containing rinse stream(22). This salt containing rinse is passed into a reverse osmosis unit (23) toform a high salinity reject stream (24) rejected to a deep well (26), and aproduct discharge stream (25), which may be safely discharged (27).