The objective of this study was to investigate the operating condition and the design parameter for the BNR in STP by 4 stage BNR with media. The effulent of primary settler in STP was fed to the pilot plant. The hydraulic retention time(HRT), temperature, COD/TKN ratio and COD/TP ratio were varied to examine the removal efficiency. In the HRT of 10, 8, 6 and 6hr(winter) at media reactor, the removal efficiencies of BOD, COD, SS, TN and TP were 80∼93.9%, 88∼92.7%, 86.2∼92.4%, 41.8∼62.6%, 43.3∼64.4% respectively, and showed the best efficiency at 6hr because of optimim organic loading rate. The media reactor could obtain a stable effulent quality in range of SNR of 1.5∼2.5㎎TKN/gMLVSS·hr by temperature and SDNR 2.2∼3.2㎎NO₃/gMLVSS·hr by COD/TKN ratio and COD/TP ratio due to the biomass. |
|