Dye wastewater treatment and membrane fouling in a moving bed-UV-photocatalytically modified membrane bioreactor

Abstract

A moving bed-UV-photocatalytically modified membrane bioreactor (MB-UVPMBR) system effectively removed organic matter, and the removal efficiency of Lanasol blue 3R (LB) reached 85.1%, which was significantly greater than that of a moving bed membrane bioreactor (MBMBR) system. The dye removal efficiency of the system was enhanced as a result of the degradation of LB by a polyvinylidene fluoride (PVDF)/TiO₂-modified membrane under UV irradiation. An analysis of the membrane resistance distributions of the two systems revealed that the main cause of membrane fouling was the deposition of a cake layer on the membrane surface. Compared with the membrane in the MBMBR system, the membrane in the MB-UVPMBR system exhibited a 67.5% reduction in total filtration resistance, which was attributed to the hydrophilicity and photocatalytic properties of the PVDF/TiO₂-modified material. Overall, the removal efficiency of organic pollutants in the MB-UVPMBR system was better than that in the MBMBR system.