铁碳微电解/H_2O_2混凝法处理焦化废水的试验研究

TREATMENT OF COKING WASTEWATER BY IRON-CARBON MICROELECTROLYSIS/H_2O_2 COAGULATION PROCESS

采用一次铁碳微电解/H2O2混凝-二次铁碳微电解/H2O2混凝法处理高色度、高COD、高毒性的焦化废水。试验确定的工艺条件:(1)铁碳微电解/H2O2法去除COD的最佳条件:pH为2、H2O2投加量为4.4mL·L-1、反应时间为180min、铁屑投加量为30g·L-1、m(Fe):m(C)为3:1。(2)铁碳微电解/H2O2法去除色度的最佳条件:pH为3、H2O2投加量为1.8mL·L-1、反应时间为120min、铁屑投加量为30g·L-1、m(Fe):m(C)为3:1。(3)混凝的最佳条件:pH为7、FeCl3的投加量为100mg·L-1、PAM的投加量为2mg·L-1。结果表明,在上述最佳工艺条件下对该废水进行处理,COD和色度去除率分别可达97%和99%以上,均可达到污水综合排放标准(GB8978-1996)中的一级标准。

A highly colored coking wastewater of high COD and highly toxic was sequentially treated by an iron-carbon microelectrolysis/H2O2 coagulation-secondary iron-carbon microelectrolysis/H2O2 coagulation process. The best working conditions were as follows：the most effective conditions on COD removal：pH 2, H2O2 dosage 4.4 mL·L-1,reaction time 180 min,iron-carbon dosage 30 g·L-1,iron/carbon ration 3;the most effective conditions on color reduction： pH 3, H2O2 dosage 1.8 mL·L-1,reaction time 120 min,iron-carbon dosage 30 g·L-1,iron/carbon ration 3;the most effective conditions of coagulation： pH 7,FeCl3 dosage 100 mg·L-1,PAM dosage 2 mg·L-1.Results showed that the combined treatment under the optimal conditions removal efficiency of COD and color were above 97% and 99%,which met the first class national wastewater discharge criteria（GB 8978-1996）.