从高碑店污水处理厂的活性污泥中分离纯化得到硫酸盐还原菌(sulfate-reducing bacteria,SRB),并以稻壳作为吸附载体将其固定在连续上升流厌氧填充床反应器中,处理镍磁黄铁矿硫酸浸出废水中的金属离子,同时研究不同进样速率下SRB对Ni2+和Fe2+的去除率及出水pH的变化。实验结果表明:当废水中Ni2+和Fe2+初始质量浓度分别为190 mg/L和110 mg/L、进样速率为2 200 mL/(d.L)(水力停留时间630 min)、pH为5.6时,出水中Ni2+和Fe2+质量浓度分别为0.4~1.0 mg/L和0.3 mg/L,去除率(质量分数)在99%以上;单位反应器容积对Ni2+和Fe2+的去除率分别可达418~684 mg/(d.L)和242~396 mg/(d.L),且处理效率稳定;出水pH达到7.2,且稳定运行。随着进水速率的增加,Ni2+和Fe2+去除率逐渐降低,当进样速率增大到9 000 mL/(d.L)(水力停留时间130 min)时,SRB对Fe2+的去除率在90%左右,而Ni2+的去除效率仅为75%;出水pH仅能达到6.4。
In order to decontaminate the nickel wastewater and to recycle the ions,a type of sulfate-reducing bacteria was isolated and purified from activated sludge,and the bacteria were immobilized by intact rice chaff in an up-flow anaerobic bed reactor.Tests were conducted for the enhanced treatment of metal ions and the bearing capability of higher ions in the wastewater.Meanwhile the removal rate of the iron and nickel ions at different inlet flow rates was investigated.The results show that more than 99%(mass fraction) of the metals are removed from solutions containing 110 mg/L iron and 190 mg/L nickel ions,when the hydraulic retention time(HRT) is shortened to 630 min and pH of the inlet is 5.6.The final concentrations of Fe2+ and Ni2+ are 0.3 mg/L and 0.4-1.0 mg/L,respectively,and the final pH is about 7.2.The removal rate of Fe2+ and Ni2+ are 242-396 mg/(d·L) and 418-684 mg/(d·L),respectively.