基于生态安全的DAT-IAT城市污水处理工艺改进研究  

Research on improvement of DAT-IAT municipal wastewater treatment process based on eco-safety

作　　者：朱爽[1] 华涛[1] 周启星[1,2] 范亚维[1] 吴琼[1] 

机构地区：[1]南开大学环境科学与工程学院,教育部环境污染过程与基准重点实验室,天津300071 [2]中国科学院沈阳应用生态研究所,中国科学院陆地生态过程重点实验室,沈阳110016

出　　处：《环境工程学报》2009年第9期1567-1572,共6页Chinese Journal of Environmental Engineering

基　　金：高等学校科技创新工程重大项目培育资金项目(707011);中国科学院陆地生态过程重点实验室资助项目

摘　　要：通过正交试验,得到了DAT-IAT工艺和A/DAT-IAT工艺处理城市污水的常规指标去除和生态毒理指标削减的最优运行条件。结果表明,在正交试验的同一工艺中,COD去除最优运行条件的出水COD值优于生态毒性削减最优运行条件的出水COD值,但前者出水的生态毒性较大。由于厌氧池的水解酸化作用,A/DAT-IAT工艺对COD和生态毒性的处理效果均优于DAT-IAT工艺,并且回流总能耗低于DAT-IAT工艺,但是出水COD仍不达标。为了降低进入工艺的COD的总量,以絮凝沉淀做为预处理工艺,并采用Al残留量最小的絮凝剂投药量以降低出水中残留Al带来的生态风险。结果表明,在COD去除最优运行条件下,具有絮凝预处理的工艺对COD的去除效果优于没有絮凝预处理的工艺。絮凝-A/DAT-IAT工艺在COD去除最优运行条件下出水COD为104.46 mg/L,满足排放标准。在毒性削减最优运行条件下,具有絮凝预处理的工艺的出水生态毒性有所上升,但是污染物的总量得到了大幅削减。絮凝-A/DAT-IAT工艺与DAT-IAT工艺相比,在污染物去除效率得到大幅增加的同时,生态毒性得到有效控制,生态安全得到了有效的保障。Optimum conditions of regular indicators removal and ecotoxicology indicators reduction of municipal wastewater treated by DAT-IAT process and A/DAT-IAT process were studied by orthogonal experiments. Results showed that in the same orthogonal experimental process, the effluents COD under the optimum COD removal conditions were better than that under the optimum ecotoxicity reduction conditions, but the effluents ecotoxicity of the former were higher than that of the latter. Because of hydrolysis-acidification, both COD and ecotoxicity of A/DAT-IAT process were better than those of DAT-IAT process, and the recycle energy demand was lower than DAT-IAT process, but the effluent COD still could not meet the discharge standard. Flocculation precipitation method was used to reduce the gross of COD in the influents, and the dose with the lowest aluminum residual was applied to reduce the effluent ecological risk. Results showed that under the optimum COD removal conditions, the processes with flocculation precipitation pretreatment had better COD removal effects than the processes without pretreatment. The effluents COD of flocculation-A/DAT-IAT process was 104.46 mg/L under the optimum COD removal conditions, and it attained the discharge standard. Under the optimum ecotoxicology reduction conditions, though the effluents ecotoxicology of the flocculation precipitation pretreatment processes were higher than that of the processes without pretreatment, the gross of pollutants removed remarkably. Compared with DAT-IAT process, the flocculation-A/DAT-IAT process could control ecotoxicology and guarantee the eco-safety effectively as well as the reduction of contamination was achieved remarkably.

关 键 词：DAT-IAT工艺 A/DAT-IAT工艺 絮凝 生态毒理指标 常规指标 

分 类 号：X703.1[环境科学与工程—环境工程]