A submerged membrane hybrid system coupled with magnetic ion exchange (MIEX®) and flocculation in wastewater treatment

Wastewater treated by conventional secondary and tertiary processes cannot be reused directly without further treatment. The membrane process can achieve a high quality effluent, but membrane fouling caused by organic matter affects membrane performance and operating cost. MIEX® resin can effectively remove the majority of small MW dissolved organic in wastewater (345–688 Dalton). Flocculation with an optimum dose of ferric chloride (24 mg/L as Fe) gave a higher removal of DOC, especially for removing the middle range of MW organics in wastewater (688–1421 Dalton). MIEX® and flocculation followed by submerged membrane system led to a very high DOC removal of more than 90–95% UVabs. This membrane hybrid system could maintain a transmembrane pressure of less than 8 kPa even after 8 h of operation thus reducing membrane fouling.