Development of Non-Cellulosic RO Systems for Seawater Desalting.

摘要

Sea water desalting through continued development and testing of the polyamide hydrazide (DP-1) film membrane in a spiral configuration is described. Results of testing of polyamide hollow fiber permeators operating at 800psi and desalting sea water in a single stage are also discussed. A process to continuously cast assymmetric DP-1film membranes of up to 36inches width was developed to supply membranes for fabrication of spiral module elements. Small spiral (2in.) elements desalted seawater at expected flux and rejection levels and maintained stable performance in the field. Most larger (4in.) elements lost salt rejection rapidly as a result of inadequate flatness of the membrane support (sailcloth) and of wrinkles in the spirally wound leaves. Leads to overcome these deficiencies through use of alternate materials and improved fabrication techniques were demonstrated. Prototype polyamide hollow fiber permeators of 8in. diameter with fiber-glass reinforced epoxy shells were fabricated. Field tests of 4in. and 8in. permeators culminated in the operation of a pilot plant producing 10,000gpd potable water at Ocean City,New Jersey. System design,pretreatment,operating methods and cleaning procedures to control fouling of the permeators in live sea water are discussed.