Study on the enrichment isolation and characteristics of denitrifying phosphorus removal bacteria

To investigate the mechanism of denitrifying phosphorus removal and provide functional strains for nitrogen and phosphorus removal, denitrifying phosphorus removal bacteria (DPB) were enriched and isolated from A²SBR. This study made use of controlling the inflow water operation mode of A²SBR for DPB enrichment and screening. The isolated DPB were complex formulated for construction of nitrogen and phosphorus removal functional bacteria. Two-stage inflow water operating mode and high inflow water rate enabled DPB to become rapidly dominant in the reactor. Five DPB strains were isolated and identified by the microbial identification system with fatty acids. The DPB strain and phosphorus accumulating organisms or denitrobactcria were complex formulated, the results showed that the best combination was b204 and 16. Its phosphorus removal rate was 85.78% and its denitrification efficiency was 75.02%, better than the single strains removal rate. Experimental results also showed that DPB could become dominant populations quickly with optimum cultivation conditions and appropriate influent.