Evaluation of inoculum sources for aerobic treatment of 2,3,4-trifluoroaniline during start-up and shock

As the typical toxic xenobiotics, the environment contamination with fluoroaromatics(FAs), especially the polyfluorinated aniline, is a serious problem all over the world. This work focused on the effects of three different seeding sources on treatment performances of 2,3,4-trifluoroaniline (2,3,4-TFA) in three SBRs during start-up and shock. Through 246~323d of acclimation, three treatment systems were able to maintain successful 2,3,4-TFA treatment, with over 95% of degradation efficiencies and 60~80% of defluorination rates at 300 mg/L. Among three seeding sources, the activated sludge obtained from the fluorizated hydrocarbon intergrated wastewater (FHS) treatment plant(no containing any FAs) was optimal, with the shortest acclimation time of 246d, the highest defluorination rate of 70~80%, the highest microbial diversity with 9 dominant bacterial groups, and the fastest recovery time of 7d after shock. Compared with the sludge from pharmaceutical wastewater containing part of municipal wastewater (PMS) treatment plant, another type of sludge for treating the chemical industrial park combined wastewater (CIS) exhibited earlier defluorination reaction, higher defluorination rate and microbial diversity, but lower shock resistance. High-throughput sequencing demonstrated an obvious reconstruction of microbial communities in three SBRs after acclimation, forming their own distinctive compositions. The most dominant phylum of PMS was Deinoccoccus-Thermus (24.43%) instead of Proteobacteria(46.68%~47.59%) in other two, and the dominant phylum Acidobacteria in FHS and CIS evidently increased. After shock, the dominant bacterial genera Blastocatellaceae, and Methylobacteriaceae in three acclimation sludge disappeared, the Thauera, Saccharibacteria, and Terrimonas became the dominant bacterial genera in FHS, and the dominant bacterial genera indluded Saccharibacteria, Meiothermus in CIS. Based on the degradation efficiency and variation of microbial communities during start-up and shock, it could be concluded that the influence of the inoculum on treatment performance of 2,3,4-TFA in SBR were remarkable, as well as the bacterial genera Blastocatellaceae, and Methylobacteriaceae could contribute to defluorination reaction. As the typical toxic xenobiotics, the environment contamination with fluoroaromatics(FAs), especially the polyfluorinated aniline, is a serious problem all over the world. This work focused on the effects of three different seeding sources on treatment performances of 2,3,4-trifluoroaniline (2,3,4-TFA) in three SBRs during start-up and shock. Through 246~323d of acclimation, three treatment systems were able to maintain successful 2,3,4-TFA treatment, with over 95% of degradation efficiencies and 60~80% of defluorination rates at 300 mg/L. Among three seeding sources, the activated sludge obtained from the fluorizated hydrocarbon intergrated wastewater (FHS) treatment plant(no containing any FAs) was optimal, with the shortest acclimation time of 246d, the highest defluorination rate of 70~80%, the highest microbial diversity with 9 dominant bacterial groups, and the fastest recovery time of 7d after shock. Compared with the sludge from pharmaceutical wastewater containing part of municipal wastewater (PMS) treatment plant, another type of sludge for treating the chemical industrial park combined wastewater (CIS) exhibited earlier defluorination reaction, higher defluorination rate and microbial diversity, but lower shock resistance. High-throughput sequencing demonstrated an obvious reconstruction of microbial communities in three SBRs after acclimation, forming their own distinctive compositions. The most dominant phylum of PMS was Deinoccoccus-Thermus (24.43%) instead of Proteobacteria(46.68%~47.59%) in other two, and the dominant phylum Acidobacteria in FHS and CIS evidently increased. After shock, the dominant bacterial genera Blastocatellaceae, and Methylobacteriaceae in three acclimation sludge disappeared, the Thauera, Saccharibacteria, and Terrimonas became the dominant bacterial genera in FHS, and the dominant bacterial genera indluded Saccharibacteria, Meiothermus in CIS. Based on the degradation efficiency and variation of microbial communities during start-up and shock, it could be concluded that the influence of the inoculum on treatment performance of 2,3,4-TFA in SBR were remarkable, as well as the bacterial genera Blastocatellaceae, and Methylobacteriaceae could contribute to defluorination reaction.