Enhanced organic matter degradation in shale gas wastewater treatment using Biofilm-Membrane bioreactors with varied filler Types, Pre-ozonation, and filler ratios

Abstract

Membrane bioreactor (MBR) is a promising technology for the treatment of shale gas wastewater (SGW); however, there exists an urgent need for improvement in the degradation of organic matter. This study delves comprehensively into the impact of different filler types within a biofilm-membrane bioreactor (BF-MBR) for the treatment of SGW. Furthermore, the impact of pre-ozonation and filler ratios on the performance of BF-MBR is explored. Through the synergistic implementation of pre-ozonation and meticulously optimized filler ratios, a significant enhancement in removing dissolved organic carbon is achieved, notably reaching 36.0%-38.3% as opposed to the initial values of 14.4%-14.9%. Remarkably, groups subjected to pre-ozonized display membrane flux levels 42.2%-53.4% higher than non-pre-ozonated group. In the pre-ozonation phase, aerogel fillers (AF) demonstrate exceptional effectiveness. AF achieves the highest DOC removal (33.3%) and UV254 removal (70.6%). At the same time, AF group has a better effect of ameliorating membrane fouling. In addition, Pseudomonas and Constrictibacter are unveiled to be significantly correlated with the organic matter removal. In essence, this study provides practical insights that serve to optimize the treatment of SGW through the BF-MBR approach, effectively addressing its inherent challenges.