A^2/O系统对雨季水量冲击负荷的适应能力研究

Adaptability of A^2/O Process to Hydraulic Impact Loads during Rainy Seasons

通过模型试验考察了雨季合流污水水量冲击负荷对A2/O系统去除污染物效果的影响,以及冲击过后恢复初始状态时对各指标的去除效果和规律。当控制F/M值基本不变,且二沉池表面水力负荷较低时,水量提高至3倍对COD、SS和TP的去除效果影响较小,出水COD、TN、TP浓度可达到一级A排放标准,出水SS可达到一级B标准。随着水量冲击负荷的提高,对COD、SS和TP的去除率呈下降趋势,但降幅不大,从1倍负荷提高至3倍负荷,去除率下降约10%;但水量负荷的提高对去除TN的影响较大,当水量负荷由1倍提高至3倍时,去除率下降了约35%;对去除TN而言,2.5倍水力负荷为极限冲击负荷。水量冲击负荷由3倍降至1倍,对COD、SS、TP的去除率较初始1倍负荷的略有下降,去除率降幅小于3%;对TN的去除率较初始1倍负荷时稍有下降,去除率降幅约为7%。

The influence of the hydraulic impact loads of combined sewage during rainy seasons on the A2/O process was studied by model tests. The removal effect of COD, TN, TP and SS was analyzed and the two conditions of initial 1 time load and recovery 1 time load were compared. The results showed that when the F/M ratio remained basically unchanged tation tank was low, and the hydraulic load increased , the surface hydraulic load of secondary sedimen- from 1 time to 3 times, the removal rates of COD, SS and TP changed little, and COD, TN and TP in the effluent could meet the first level A standard for municipal sewage discharge, and SS in the effluent could meet the first level B standard for municipal sewage discharge. When flow rate increased, the removal rates of COD, SS and TP came down, but not by much. The removal rates declined nearly by 10% when hydraulic load increased from 1 time to 3 times. But there was a big decline in the removal rate of TN when flow rate increased. When hydraulicload increased from 1 time to 3 times, the removal rate of TN declined by nearly 35%. 2.5 times hydrau- lic load was the limit impact load for TN removal. The difference between recovery 1 time load and initial 1 time load was small. The removal rates of COD, SS and TP declined by less than 3% , and the removal rate of TN declined by nearly 7%.