Bioaugmentation of a continuous-flow self-forming dynamic membrane bioreactor for the treatment of wastewater containing high-strength pyridine.

For the treatment of high-strength pyridine containing wastewater, a bioaugmented continuous-flow self-forming dynamic membrane bioreactor (CSFDMBR), which was consisted of a continuous flow airlift reactor (CFAR) and a dynamic membrane bioreactor (DMBR), was developed in this study. The results indicated that through the bioaugmentation by Rhizobium sp. NJUST18, CSFDMBR could be successfully started, which was confirmed by complete removal of pyridine, efficient nitrification, and significant increase of biomass. Pyridine could be effectively degraded in the CSFDMBR even at influent pyridine loading rate as high as 9.0 kg m-3 day-1, probably due to the efficient biomass retention in the CSFDMBR, which could be attributed to the formation of aerobic granules and the key role of dynamic membrane. CSFDMBR presented good polishing performance in treating pyridine wastewater, with effluent total organic carbon (TOC) and turbidity as low as 22.5 ± 6.8 mg L-1 and 3.8 ± 0.5 NTU, respectively. Membrane fouling could be effectively controlled, as indicated by backwash period as long as 60 days. The observed efficient performance highlights the potential for the full-scale application of the bioaugmented CSFDMBR, particularly for highly recalcitrant pollutant removal.