两段生物膜法处理城市污水厂出水

Advanced treatment of municipal sewage plant effluent by two-stage bio-contact oxidation process

采用两段生物膜法对城市污水处理厂出水进行深度处理实验研究，主要研究系统对氨氮和COD的处理效果及水力停留时间、回流比和温度的影响．实验结果表明，最佳水力停留时间为1h，最佳回流比为100％；在此条件下系统运行12个月，运行期间氨氮和COD的进水浓度范围分别为1．37～19．95mg／L和14．40～37．50mg／L时，出水浓度范围分别为0．01～3．15mg／L和7．36～19．02mg／L，平均去除率分别为97．05％和39．96％．氨氮和COD的去除率在2月份最低，分别为82．50％和14．40％；5月份最高，分别为98．50％和48．50％．出水中两项水质指标达到设计标准．

Two-stage biofilm contact oxidation process is used to treat the effluent of municipal sewage plant. In the treatment the optimal hydraulic residence time （HRT） is 1 hour and the optimal reflux ratio is 100%. The concentration of NH3-N is from 1.37 to 19.95 mg/L and the concentration of COD from 14. 40 to 37.50 mg/L in influent, respectively. The effluent concentrations of NH3-N and COD are 0. 01 ～ 3.15 mg/L and 7.36 ～ 19.02 mg/L under the optimal conditions. The mean removal rates of NH3-N and COD are 97.05% and 39.96%. The two main water quality indicators can achieve the designed standard. The maximum removal rates NH3-N and COD of 98.50% and 48.80% appear in May. The minimum removal rates of NH3-N and COD of 82. 50% and 14. 40%, respectively, appear in February during the one-year experiment.