悬浮载体复合MBR工艺处理电镀废水效能研究

Efficiency of electroplating wastewater treatment by suspended carrier integrated with MBR technology

为探究高效经济的电镀废水处理工艺,本研究采用悬浮载体复合MBR工艺(HMBR)与普通MBR工艺平行运行,以重金属离子Cu^(2+)、Ni^(2+)、Cr(VI)为代表,重点研究了不同浓度重金属冲击下对两种工艺处理电镀综合废水效能及微生物活性的影响,以及载体的介入对膜污染的控制作用和对微生物种群多样性的影响.实验结果表明:在Cu^(2+)、Ni^(2+)、Cr(VI)浓度5~30mg/L冲击下,HMBR工艺对COD和NH_4^+-N去除效率分别在60%和40%以上,而普通MBR工艺对COD、NH_4^+-N的去除率分别为30%和15%以上.随着重金属Cu^(2+)、Ni^(2+)、Cr(VI)浓度的升高,MBR反应器内活性污泥的污泥浓度及SOUR逐步下降,HMBR工艺SOUR受抑制率48.9%远小于普通MBR工艺的73.9%.HMBR系统中EPS分泌显著低于普通MBR工艺,有效减缓膜污染的速率.此外,投加载体增加了反应系统中微生物种群多样性.

In order to study an efficient and economical treatment process of electroplating wastewater,parallel operation of suspended carrier composite MBR(HMBR)and ordinary MBR process was adopted.With Cu^2+,Ni^2+and Cr(VI)as the main indicators,this study mainly focused on the impact of different heavy metals concentrations on the electroplating wastewater treatment efficiency and the microbial activity.The influence of carrier intervention on membrane fouling and microbial population diversity were also studied.The experimental results showed that the removal efficiency of COD and NH4^+in HMBR was over 60%and 40%respectively with the concentrations of Cu^2+,Ni^2+and Cr(VI)(5~30mg/L),while that in the MBR was over 30%and 15%.With the increasing of Cu^2+,Ni^2+and Cr(VI)concentrations,the concentrations of sludge and SOUR in the normal MBR declined gradually.The SOUR inhibition rate of 48.9%in HMBR by heavy metal was far less than that of 73.9%in normal MBR.The secretion of EPS in HMBR was significantly lower than that in ordinary MBR process,which effectively slowed down the rate of membrane fouling.In addition,the addition of carriers increased the diversity of microbial populations in the reaction system.