Simultaneously ammonium and perchlorate remove via the partial nitrification-anammox coupled sulfur autotrophic system

In this study, partial nitrification-anammox coupled sulfur autotrophic (PNA-SA) system was constructed for removing ammonium and perchlorate from composite wastewater simultaneously. The removal rates of ammonium and perchlorate could reach 94.2% and 93.1%, respectively, at an ammonium concentration of 60 mg N∙L⁻¹ and a perchlorate concentration of 30 mg N∙L⁻¹. Ammonium was mainly removed by anammox bacteria (AnAOB) in PNA reactor, while perchlorate removal was attributed to perchlorate reducing bacteria (PRB) in SA reactor. Furthermore, combined with Pearson analysis, N-acylhomoserine lactones (AHLs)-mediated quorum sensing regulated the production of TB-EPS, improving biofilm stability and thus ensuring the removal performance of reactors. 16sRNA gene sequencing results indicated that the key functional bacteria in the PNA reactor were Comamonas and Candidatus Kuenenia, and the key functional bacteria in the SA reactor were Sulfurimonas, Thiobacillus, and Defluviimonas. These key functional bacteria ensured PNA-SA system feasibility and stability. Such results indicated that PNA-SA system could be used to treat ammonium and perchlorate composite wastewater, thereby providing a new strategy for removing such composite wastewater.