采用A/O-MBR工艺处理模拟生活污水,考察了投加不同浓度的氯化铁对该工艺去除营养物效能及膜污染的影响。结果表明,氯化铁浓度对该工艺去除NH+4-N的影响不大,对COD及TN的去除效能则有所改善;在投加量为100 mg/L时,对TP的去除率达到最高,为91.7%,出水浓度维持在0.42 mg/L左右。此外,投加一定量的氯化铁可以有效降低污泥絮体的Zeta电位,增大污泥絮体的粒径,降低胞外聚合物(EPS)中多糖的含量,进而有效地延缓了膜污染速率。对膜表面污染物的红外光谱分析表明,氯化铁投加量的变化并没有改变其组分。
The anoxic/oxic membrane bioreactor (A/O -MBR) was utilized to treat synthetic do- mestic sewage, and the influence of different concentrations of ferric chloride on nutrient removal efficien- cy and membrane fouling were investigated. The results revealed that different concentrations of ferric chloride had little impacl on the removal efficiency of NH4 - N, but the removal efficiencies of chemical oxygen demand (COD) and total nitrogen (TN) were improved to some extent. When the dosage of fer- ric chloride was 100 mg/L, the removal efficiency of total phosphorus (TP) was optimal, which reached 91.7%, with an average effluent TP of 0.42 mg/L. It was also found that a certain amount of ferric chlo- ride could effectively reduce Zeta potential of sludge flocs, increase particle size of sludge flocs and de- crease the carbohydrates in extracellular polymeric substances (EPS), which retarded the membrane fouling rate. Fourier transform infrared spectroscopy showed that the composition of membrane foulants was not changed by different dosages of ferric chloride.