基于周期换向技术的靛蓝染色废水电絮凝处理

lectrocoagulation Treatment of Indigo Dyeing Wastewater Based on Periodic Reversal Technology

为降低极板腐蚀和电能消耗,实现对悬浮污染物的有效分离,以铁、铝金属为电极,探究周期换向技术条件下施加电压、时间、电解初始pH值等参数对电絮凝效果的影响,并检测极板腐蚀情况和溶解效率。结果表明:在周期换向电源下,施加电压25V时,设定铁-铝电极极板间距为2cm,废水初始pH值为5.00,经过25min电絮凝后,废水上清液COD值为180.7mg/L,脱色率达99.00%,絮凝率为86.10%,显示出优异的电絮凝效果。与直流电源相比,周期换向电化学体系中,电极腐蚀及钝化现象得到有效缓解,铁、铝电极的损失率仅为0.6%,溶解效率高于80.0%;COD去除比能耗为0.39,相当于直流电源的27.3%.

In order to reduce electrode corrosion and energy consumption and achieve effective separation of suspended pollutants,the effects of applied voltage,time and initial pH of electrolysis on the electroflocculation were investigated under the condition of periodic commutation technique with iron and aluminum electrodes.The corrosion and dissolution efficiency of the electrode were monitored.The results show that after 25 min of electroflocculation,the COD value of the supernatant is 180.7 mg/L,the decolorization rate is 99.00%,and the flocculation rate is 86.10%.Other conditions were as follows:applied voltage of 25 V,electrode spacing of 2 cm and an initial pH of 5.00 in the wastewater,where electroflocculation is effective.Compared with the DC power supply,the corrosion and passivation of electrodes in the periodic reversal electrochemical system are effectively alleviated,the loss rate of iron and aluminium electrodes is only 0.6%,and the dissolution efficiency is higher than 80.0%;the specific energy consumption of COD removal is O.39,which is equivalent to 27.3%of the DC power supply.