Fouling inhibition of RO membrane separation by two-stage H2O2/UV pre-oxidation for municipal wastewater reuse

Abstract

a b s t r a c tThis study evaluated the performance of combining two-stage H 2 O 2 /UV pre-oxidation with RO post-separation for the reuse of municipal wastewater. The results demonstrated that the two-stage H 2 O 2 /UV (H 2 O 2 = 0-30 mg/L) process was more effective than the one-stage (H 2 O 2 = 0-60 mg/L) process for mitigating RO membrane organic-fouling and bio-fouling. In thetwo-stage operation, the inactivated log reduction of microorganisms reached 4.96-logs, and the total organic carbon (TOC) was reduced from 18.0 to 2.98 mg/L. The silt density index (SDI) decreased from 9.8 to 3.9; the normalized flux decline (r) of RO separation was enhanced from 36% to 91%.