接续A^2O的气浮过滤污水深度处理工艺研究

Study of Dissolved Air Flotation-Filtration on A^2O Process for Advanced Wastewater Treatment

探究混凝-溶气气浮-过滤工艺在污水深度处理方面的可行性。以武汉市某污水处理厂A^2O工艺二沉池出水为原水,进行了混凝-溶气气浮-过滤深度处理工艺中试研究。试验完成了分流比、加药量、表面负荷3个主要影响因素的三因素三水平正交实验,以COD、总磷、浊度去除率为考察指标,结果表明:加药量对COD、总磷、浊度去除效果影响均最为显著,推荐工艺最佳运行参数为表面负荷11.11 m^3/(m^2·h),加药量10 mg/L,分流比12%,且在此运行条件下,单位水处理电耗与药耗总共为0.039元/m3;同时在固定表面负荷10 m^3/(m^2·h)条件下进行了连续流实验,结果表明:在一定水质波动条件下,该工艺连续运行可靠、处理效果稳定,出水COD浓度稳定低于15 mg/L、出水总磷浓度稳定低于0.1 mg/L,出水浊度低于0.5 NTU,有一定工程应用前景。

To explore the feasibility of the coagulation-dissolved air flotation（ DAF）-filtration process in the advanced wastewater treatment,a pilot study on the coagulation-dissolved air flotation-filtration advanced treatment process was carried out in a sewage treatment plant of Wuhan with the effluent from the secondary sedimentation tank of A^2O process as raw water. The experiment completed the three factors and three levels orthogonal experiment of split ratio、dosage of coagulant、surface load three factors,COD、TP、turbidity removal rate as the evaluation index,the results showed that the dosage had the most significant effect on the removal of COD,total phosphorus and turbidity.The optimum operating parameters of the recommended process were surface load of 11.11 m^3/（m^2·h）,dosage of 10 mg/L and split ratio of 12%. Under this operating conditions,the unit water treatment power consumption and drug consumption for a total of 0.039 yuan/m^3; At the same time,the continuous flow test was carried out under the condition of fixed surface load of 10 m^3/（m^2·h）. The results showed that under a certain water quality fluctuation condition,the process was reliable,the treatment effect was stable,the effluent COD concentration was stable below 15 mg/L,The concentration is stable below 0.1 mg/L,the turbidity of the effluent is less than 0.5 NTU,which has certain engineering application prospect.