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.

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.