倒置A^2/O工艺处理城镇河道污水的效能研究

Treatment Efficiency of City River Wastewater by Inverted A^2/O Process

采用连续流的倒置A2/O工艺处理深圳市布吉河水,考察了对COD、NH4+-N、TN、TP的去除效果,以便为新建污水处理厂提供技术参数。结果表明,在总水力停留时间为11 h的条件下,即使在冬季对布吉河水中的污染物仍有良好的去除效果。当进水COD为160～322 mg/L、TN为25.5～64.3 mg/L、TP为2.85～3.96 mg/L、NH 4+-N为24.0～60.2 mg/L时,出水COD为27～63 mg/L、TN为6.46～35.2 mg/L、TP为1.24～2.0 mg/L、NH 4+-N为0.25～29.23 mg/L,平均去除率分别达到82.5%、65.7%、50.1%、88.7%。为进一步降低出水的TP浓度,进行了混凝强化除磷试验。当聚合氯化铝的投量为60 mg/L时,经混凝后出水TP降至0.09～0.48 mg/L,平均为0.32 mg/L,达到了《城镇污水处理厂污染物排放标准》(GB 18918—2002)的一级A标准。

The continuous flow inverted A^2/O process was used to treat Buji River wastewater, Shenzhen, and the removal efficiencies of COD, NH4 - N, TN and TP were investigated to provide technical support for newly built wastewater treatment plants. Even if in winter, good removal efficiency of pollutants from Buji River wastewater can be achieved when HRT is 11 h. When the influent COD, NH4^＋ - N, TN and TP are 160 to 322 mg/L, 24.0 to 60.2 mg/L, 25.5 to 64.3 mg/L and 2.85 to 3.96 mg/L respectively, their effluent concentrations are 27 to 63 mg/L, 0.25 to 29.23 mg/L, 6.46 to 35.2 mg/L and 1.24 to 2.0 mg/L respectively, and the average removal rates reach 82.5% , 88.7% , 65.7% and 50.1% respectively. Chemically enhanced phosphorus removal was carried out to further decrease TP concentration in the effluent. When PAC dosage is 60 mg/L, the effluent TP is decreased to 0.09 to 0.48 mg/L, with an average of 0.32 mg/L, reaching the first level A criteria specified in D/scharge Standard of Pollutants for Municipal Wastewater Treatment Plant （ GB 18918 - 2002 ）.