Impact of reactor configuration on treatment performance and microbial diversity in treating high-strength dyeing wastewater: Anaerobic flat-sheet ceramic membrane bioreactor versus upflow anaerobic sludge blanket reactor

Abstract

In this study, an anaerobic flat-sheet ceramic membrane bioreactor (AnCMBR) was used to treat high-strength dyeing wastewater, and compared with an upflow anaerobic sludge blanket (UASB) reactor. The start-up phases of the AnCMBR and UASB reactor were accomplished within 60 d by using cultivated seed sludge. The results showed that the AnCMBR had better COD, TN, and TP removal rates than the UASB reactor. The CH₄ production of the AnCMBR was higher than that of the UASB reactor. The AnCMBR was operated with low energy consumption due to good water permeability of the flat-sheet ceramic membrane. The AnCMBR and UASB reactor had similar CH₄-producing Archaea; Methanosaeta, Methanosarcina, and Methanomassiliicoccus were the most abundant. The AnCMBR had a higher proportion of Desulfovibrio sp. and Desulfomicrobium sp., which are reported to have the potential to degrade reactive dyes. A large number of sulfate-reducing enzymes were deduced to contribute to the sulfate-reducing pathway.

Keywords: Anaerobic membrane bioreactor; Decolorization; Membrane fouling; Microbial diversity; Seed sludge.