A new biological nitrogen removal process,which is named herein“The circulating fluidized bed bio-reactor(CFBBR)”,was developed for simultancous removal of nitrogen and organic matter.This process was composed of an...A new biological nitrogen removal process,which is named herein“The circulating fluidized bed bio-reactor(CFBBR)”,was developed for simultancous removal of nitrogen and organic matter.This process was composed of an anaerobic bed(Riser),aerobic bed(Downer)and connecting device.Influent and nitrified liquid from the acrobic bed enters the anaerobic bed from the bottom of the anaerobic bed,completing the removal of nitrogen and organic matter.The system performance under the conditions of different inflow loadings and nitrified liquid recirculation rates ranging from 200% to 600% was examined.From a technical and economic point of view,the optimum nitrifed liquid recirculation rate was 400%.With a shortest total retention time of 2.5 h(0.8 h in the anaerobic bed and 1.5 h in the aerobic bed)and a nitified liquid rocir-culation rate of 400% based on the influent flow rate,the average removal efficiencies of total nitrogen(TN)and sol-uble chemical oxygen demand(SCOD)were found to be 88% and 95%,respectively.The average efluent concentra-tions of TN and SCOD were 3.5 mg/L and 16 mg/L,respoctively.The volatile suspended solid(VSS)concentra-tion,nitrifcation rate and denitrification rate in the system were less than 1.0 g/L,0.0260.1 g NH_(4)^(+)-Ng VSS-d,and 0.016-0.074g NO_(x)^(-)-Ng VSS-d,respectively.展开更多
基金This work was supported by the Key Project of Chinese Ministry of Education(No.205198).
文摘A new biological nitrogen removal process,which is named herein“The circulating fluidized bed bio-reactor(CFBBR)”,was developed for simultancous removal of nitrogen and organic matter.This process was composed of an anaerobic bed(Riser),aerobic bed(Downer)and connecting device.Influent and nitrified liquid from the acrobic bed enters the anaerobic bed from the bottom of the anaerobic bed,completing the removal of nitrogen and organic matter.The system performance under the conditions of different inflow loadings and nitrified liquid recirculation rates ranging from 200% to 600% was examined.From a technical and economic point of view,the optimum nitrifed liquid recirculation rate was 400%.With a shortest total retention time of 2.5 h(0.8 h in the anaerobic bed and 1.5 h in the aerobic bed)and a nitified liquid rocir-culation rate of 400% based on the influent flow rate,the average removal efficiencies of total nitrogen(TN)and sol-uble chemical oxygen demand(SCOD)were found to be 88% and 95%,respectively.The average efluent concentra-tions of TN and SCOD were 3.5 mg/L and 16 mg/L,respoctively.The volatile suspended solid(VSS)concentra-tion,nitrifcation rate and denitrification rate in the system were less than 1.0 g/L,0.0260.1 g NH_(4)^(+)-Ng VSS-d,and 0.016-0.074g NO_(x)^(-)-Ng VSS-d,respectively.