铝铁电极换向电源电凝聚法处理活性黑KN-B染料废水的研究  

Research on the treatment of Active Black KN- B wastewater by electro-coagulation method using iron and aluminum electrode with alternate pulse

作　　者：付忠田[1] 孙兆楠[1] 胡筱敏[1,2] 朱茂森[1] 

机构地区：[1]东北大学资源与土木工程学院,沈阳110004 [2]沈阳建筑大学市政与环境工程学院,沈阳110004

出　　处：《安全与环境学报》2010年第4期31-37,共7页Journal of Safety and Environment

基　　金：沈阳建筑大学省级重点实验室开放基金项目

摘　　要：针对普通电凝聚技术处理染料废水过程中采用单向电流易造成阳极损耗增加处理成本的缺点,对传统的电凝聚法进行改进,采用换向电源、铝铁分别作为两极的新型电化学反应器,以色度和COD_(Cr)去除率作为指标,利用电凝聚技术处理活性黑KN-B染料模拟废水。通过周期性改变电解电流方向,实现金属铝和铁电极均可溶解,同时产生具有絮凝作用的金属离子,并减缓金属阳极的损耗速度。结果表明,该方法对活性黑KN-B模拟染料废水具有较好的处理效果。其最佳处理条件为:电解时间30min,电解电压10V,电源换向周期10s,染料质量浓度100～300mg/L,电解质(Na_2SO_4)浓度0.01mol/L,搅拌速度1000r/min,极板间距1.0cm,pH=5～9。在此条件下,色度去除率可达99%以上,COD_(Cr)去除率可达50.0%以上。电解时间、电解电压、换向周期、染料质量浓度、电解质(Na_2SO_4)浓度、搅拌速度、极板间距、pH值等因素对色度和COD_(Cr)去除率均有一定程度影响。色度主要是由于活性黑KN-B染料发生化学反应,染料分子中的发色基团—N=N—键被打开,生成苯环衍生物而得到去除;COD_(Cr)的去除则主要是絮凝和气浮现象共同作用的结果。扫面电镜测试(SEM)结果表明,该方法可以有效减缓阳极损耗过程。In order to avoid the disadvantages of unilateral current such as anode wastage and high cost in the application of electro-coagulation method for dye wastewater treatment, ahernate pulse electro-coagulation was used instead to treat the simulated Active Black KN- B dye wastewater. Decoloration capability and the removal of chemical oxygen demand （COD） of the simulated dye wastewater were evaluated for the utilization of iron and aluminum as opposite electrodes in electro-coagulation system. In this method either anode or cathode will dissolve when the alternate pulse from the electrical source was applied. The ions which possess the ability of flocculation will be produced at the same time. Hence, the anode will be protect- ed and the consumption of electrode will be slowed down. The effect of different operational parameters such as the electrolysis time, ap- plied voltage, ahernate cycle, stirring speed, initial pH and dye concentration, electrode gap as well as the concentration of electrolyte were studied in order to achieve higher dye removal efficiency. The experiment results showed that lhe optimum operating conditions were as follows： electrolysis time ： 30 min, voltage = 10 V, alternate cycle = 10 s, stirring speed = 1 000 r/min, dye conc, entration = 100 300 mg/L, concentration of electrolyte （Na2SO4） = 0.01mol/L, electrode gap = 1.0 cm and initial pH = 5 - 9. Decoloration rate can go up to 99% and the removal rate of CODer was 50% and above. All of the parameters can affect the decoloration and the removal of chemical oxygen demand （COD） with different extent. Decoloration is mainly due to the chemic reaction of the Active Black KN B dye, where the configuration of=N = N-- was altered and phenyl ramification was formed. The removal of CODcr was resulted from the floeculation and floatation. The SEM characterization showed that the consumption of electrode can be effectively slowed down by this method.

关 键 词：环境工程学 铝铁电极 阳极损耗 周期换向 电凝聚 染料废水 

分 类 号：X506[环境科学与工程—环境工程]