Achieving single‐stage partial nitritation and anammox (PN/A) using a submerged dynamic membrane sequencing batch reactor (DM‐SBR)

Abstract

Single-stage partial nitration and anammox (PN/A) process was achieved in a sequencing batch reactor (SBR) using a submerged dynamic membrane (DM) in this study. The reactor was stably operated for 200days, and the nitrogen removal efficiency (NRE) was sustained at 70.3±7.2% at a nitrogen loading rate (NLR) ranging from 0.1 to 0.3kgNm-3 day-1 with a hydraulic retention time (HRT) of 24hr. When the NLR was 0.2kgNm-3 day-1 , the NRE achieved was high as 80% with a low concentration of dissolved oxygen (DO) of 0.13mg/L. In addition, the specific activity of anammox bacteria and ammonia-oxidizing bacteria (AOB) reached was 2.72 and 16.80gNgVSS-1 day-1 , respectively. The DM intercepted the biomass due to the lamellar, intact, dense biofilm self-generated on the surface of the supporting material, which had an effluent turbidity of 10 NTU. The enriched anammox functional bacteria were Candidatus Jettenia (11.06%) and the AOB-like functional bacteria consisted primarily of Nitrosomonas, with a relative abundance of 2.76%, which ensured the PN/A process proceeding. This study provides a novel reactor configuration of the single-stage PN/A process in the view of practical applications. PRACTITIONER POINTS: Single-stage partial nitration and anammox (PN/A) process was achieved using a submerged dynamic membrane (DM) in this study. The reactor was stably operated for 200days, and the nitrogen removal efficiency was sustained at 70.3±7.2%. The feasibility of the PN/A system with DM is evaluated. The main objective is to provide a control strategy of the DM-SBRs for practical applications.