丙烯腈生产废水中氰及腈类化合物对硝化作用影响的模拟研究

Simulation Study on the Effect of Cyanide and Nitrile Compounds on Nitrifi cation in Acrylonitrile Production Wastewater

丙烯腈生产废水存在的丙烯腈、乙腈、氰化物等有毒有害物质对活性污泥的硝化过程产生严重的抑制作用,极大的影响了废水中氨氮的去除。笔者采用SBR反应器进行生化小试模拟试验,分别研究了不同含量丙烯腈、乙腈和氰化物对活性污泥系统中硝化细菌去除氨氮效果的影响。实验结果表明,当进水丙烯腈浓度<80mg·L^(-1)、乙腈浓度<800mg·L^(-1)时,出水NH_(3)-N浓度低于1mg·L^(-1),去除率在99%左右,对该活性污泥系统中的硝化过程基本没有抑制作用;TCN<5mg·L^(-1)时,NH_(3)-N的去除率为90%左右,对硝化过程有一定的抑制作用但较小,TCN>10mg·L^(-1),NH_(3)-N的去除率降至60%以下,对硝化过程的抑制作用较大。

Acrylonitrile,acetonitrile,cyanide and other toxic and harmful substances present in acrylonitrile production wastewater have a serious inhibitory effect on the nitrification process of activated sludge,which greatly affects the removal of ammonia nitrogen in wastewater.The au-thor used SBR reactor to conduct a biochemical experiment simulation experiment,and studied the effects of different contents of acrylonitrile,acetoni-trile and cyanide on the effect of nitrifying bacteria on the removal of ammonia nitrogen from activated sludge system.Experimental results show that the concentration of acrylonitrile in the inlet water<80 mg·L^(-1),acetonitrile concentration<800 mg·L^(-1),the effluent NH_(3)-N concentration is less than 1 mg·L^(-1),the removal rate is about 99%,and there is basically no inhibitory effect on the nitrification process in the activated sludge system;TCN<5 mg·L^(-1),the removal rate of NH_(3)-N is about 90%,which has a certain inhibitory effect on the nitrification process but is small,TCN>10 mg·L^(-1),NH_(3)-N removal rate is reduced to less than 60%,the inhibition effect on the nitrification process is greater.