【摘要】 采用高密度澄清器处理初期雨水,以减轻其对南淝河水体的污染。通过改变高密度澄清器的进水流量、加药量以及运行条件,确定本工艺的最佳流量以及不同降雨污染负荷对应的最佳投药量,并保证工艺能在尽量减少药剂成本的状况下运行。在流量为60 m3/h的条件下,SS去除率最高可达91.6%,CODCr去除率最高达63.8%,出水水质良好;对于进水SS、CODCr的质量浓度分别在200~350、150~300 mg/L的小雨,取PAC、PAM的投加量分别约为20、1.2 mg/L。对于进水SS、CODCr的质量浓度分别在600~900、300~600 mg/L的大雨,取PAC、PAM的投加量分别约为30、1~2 mg/L,可以经济有效地达到最佳去除率;运行一段时间后,开启污泥回流系统,并将加药量降低到原加药量的50%~60%,这样既可降低污水处理成本,又能有效去除污染物。更多还原

【Abstract】 For the purpose of reducing the pollution of Nanfei River caused by initial rainwater,densadeg was used to treat the initial rainwater.Through changing the influent flow rate,chemical dosage and operation condition,the optimal flow rate of the said process and the proper dosage of chemical corresponding to different pollution loads of rainwater were determined,which ensured normal operation of the said process with minimal cost of chemical.When the flow rate of the influent water was 60 m3/h,the maximal removal rates of SS and CODCr reached 91.6% and 63.8% respectively,the effluent water quality was good;for the rainwater with influent SS and CODCr concentrations of 200-350 and 150-300 mg/L respectively,the optimal dosage of PAC and PAM were 20 and 1.2 mg/L respectively.For the rainwater with influent SS and CODCr concentrations of 600-900 and 300-600 mg/L respectively,the optimal dosage of PAC and PAM were 30 and 1-2 mg/L respectively.With the proper dosage of chemical,the highest removal rates of pollutants could be obtained economically and effectively.After a period of operation,the sludge recirculation system started to work,and then,the chemical dosage was reduced to 50-60 percent that of the initial dosage,so as to cut down the cost of sewage treatment and maintain high pollutants removal rates at the same time.更多还原