AB工艺化学强化除磷试验研究

取吸附－生物降解（AB）工艺B段曝气池进水，投加硫酸铝（AS）和聚丙烯酰胺（PAM）进行化学除磷小试实验，考察了不同投药量下总磷、COD、氨氮和浊度的去除效果，确定了最佳投药量以及化学法和生物法在去除总磷、氨氮、COD和浊度等方面的相互关系。结果表明，AS和PAM复配对B段污水中总磷有很好的去除效果，AS投加量（以Al2O3计）为9.45mg/L，PAM为0.05mg/L时，TP、COD、氨氮和浊度去除率平均为89.2%、37.7%、71.6%和2.41%。曝气过程中投加AS和PAM复配化学强化除磷，总磷、COD、浊度去除率分别提高了7.3～59.2%、5.0～20.3%、10.9～34.7%，但不能提高氨氮的去除率；在溶解氧足够时，本研究投加量范围的AS和PAM的加入对硝化作用无影响；后置混凝对TP、COD、浊度的去除效果优于同步混凝,但需增加混凝沉淀设备，因此同步混凝更适合于于AB工艺的化学强化除磷改造。

Study on Chemical Enhanced Coagulation for Phosphorus Removal of Adsorption-Biodegradation Process

Chemical coagulation by adding aluminum sulfate (AS) and polyacrylamide (PAM) for phosphorus removal from influent of Unit B in adsorption-Biodegradation (AB) process was investigated in lab scale experiment. The influences of different dosages on the removal of total phosphorus (TP), chemical oxygen demand (COD), ammonia nitrogen (NH4+-N) and turbidity, and the optimal dosage as well as the relation between chemically enhanced process and biological process in terms of removal of phosphorus, COD, NH4+-N and turbidity were evaluated. The results indicated that it was effective in removing TP by compounding of AS and PAM. The average removal efficiency (RE) of TP, COD, NH4+-N and turbidity was 89.2%, 37.7%, 71.6% and 2.41% at the dosage of AS (calculated by Al2O3) and PAM of 9.45 mg/L and 0.05mg/L，respectively. The RE of TP, COD and turbidity except NH4+-N in the aeration process by adding AS and PAM for enhanced chemical phosphorus removal increased by 7.3~59.2%, 5.0~20.3% and 10.9~34.7%, respectively. Given enough dissolved oxygen, the nitrification was not affected by adding AS and PAM in the dosage range of the study. The RE of TP, COD and turbidity by postpose coagulation were better than by simultaneous coagulation, however, coagulation and sedimentation equipments were needed in postpose coagulation process. Therefore simultaneous coagulation was more suitable for transformation of AB process for chemically enhanced phosphorus removal.