活性污泥2号模型用于城市污水处理厂脱氮除磷改造的研究

Application of ASM No.2 to the study of upgrading WWTP for biological nitrogen and phosphorus removals

利用自行开发的活性污泥 2号模型ASMNO .2计算机模拟程序对重庆市某污水厂三种脱氮除磷改造方案 (A O ,A2 O ,倒置A2 O)进行了模拟研究 ,寻求了每一种方案的最佳运行控制参数 .结果表明 :(1)将现有曝气池前端 1 4控制为缺氧而形成A O工艺 ,缺氧区溶解氧浓度为 0 .10mg L ,混合液内回流比为 10 0 % ,可以使TN去除率达到 5 8.6 % ,提高 2 4个百分点 ,TP基本不受影响 ;(2 )将现有曝气池前端 12 %控制为厌氧区 ,2 4 %控制为缺氧区 ,缺氧区溶解氧浓度为 0 .10mg L ,混合液内回流比为 10 0 % ,可以使TN去除率达到 6 2 .1% ,提高约 2 8个百分点 ,TP去除率达到 78.3% ,提高 37个百分点 ;(3)倒置A2 O工艺与常规A2 O工艺的出水水质基本相当 ,但倒置A2 O工艺在工程实践中更易于实现 ;(4)三种工艺出水COD和氨氮均能达到国家规定的一级排放标准 .

The performance of three schemes(A/O,A 2/O,reverse A 2/O) of upgrading for biological nitrogen and phosphorus removal in some WWTP in Chongqing were predicted and the optimum operational parameters of each scheme were sought through the computer simulation program based on IWA ASM No.2. The results showed that : (1) The efficiency of TN removal could be increased from 34.2% to 58.6% by A/O process, if 1/4 of the existing aeration pond was converted to anoxic zone with dissolved oxygen concentration of 0.10 mg/L in the anoxic zone and the inner cycle mixed liquid ratio of 100%. Meanwhile, the TP was hardly influenced. (2) The efficiency of the TN removal could be increased from 34.2% to 62.3% and the TP from 41.7% to 78.3% in A 2/O process, if 12% of the existing aeration pond was converted of anaerobic zone and 24% to anoxic zone, with dissolved oxygen concentration of 0.10 mg/L in the anoxic zone and the inner cycle mixed liquid ratio of 100%. (3)The effect of the reverse A 2/O process was almost same to the A 2/O process, but the former was more feasible in practice. (4)The effluent COD and NH\++ 4-N concentrations could meet the standard.