建立柱实验装置,探讨了反应柱中填加介质、硝酸盐的初始浓度及不同过水流速时硝酸盐的去除效果及产物的生成情况。4种不同材料,纳米铁、真养产碱杆菌、纳米铁与真养产碱杆菌简单混合体、纳米铁与真养产碱杆菌驯化培养5 d的复合体,分别与初始浓度为65 mg/L硝酸盐溶液反应。结果表明,经培养5 d的纳米铁-真养产碱杆菌复合体对硝酸盐的去除效果最佳,去除率可达到75%,且氨氮的生成量仅为2.99 mg/L;硝酸盐初始浓度分别为32、65和95 mg/L时,32mg/L的体系中硝酸盐的降解效果最好,去除率达78.9%且亚硝酸盐及氨氮的生成量分别为2.34 mg/L和2.89 mg/L,均低于另外2组;溶液流速为6.0 cm/h时,经驯化培养的纳米铁-真养产碱杆菌对硝酸盐的去除率达77%,当控制流速降至2.4cm/h时,亚硝酸盐氮的生成量降至0.34 mg/L。
In this study,experimental column equipment was established to explore the nitrate removal efficiency and the products under the conditions of different media,initial nitrate concentrations and flow rates.The results show that the complex obtained by mixed culture of nanoscale iron and alcaligenes eutrophus for 5 days prior to the experiment,achieves removal rate of 75% and the yield of ammonia is just 2.99 mg/L.This is the best removal effects among the 4 media,the rest of which were nanoscale iron,alcaligenes eutrophus,simplely mixed culture of fresh nanoscale iron and alcaligenes eutrophus.The degradation of the NO-3-N by the nanoscale iron-alcaligenes eutrophus achieved the best effect when initial concentration of nitrate was 32mg / L.The removal rate can achieve 78.9%,and the amounts of ammonia and nitrite generation were 2.34 mg/L and 2.89 mg/L,respectively,which was lower than that when initial concentrations of nitrate were 65 mg/L or 95 mg/L;the nitrate removal rate reached to 77% at the flow rate of 6.0 cm/h,and when the flow rate was controlled at 2.4 cm/h,the nitrite generation would lower to 0.34 mg/L.