电絮凝除硅的影响因素分析  

On the influential factors for silica-pollutant removing by electrocoagulation

作　　者：支苏丽[1] 张书廷[1] 

机构地区：[1]天津大学环境科学与工程学院,天津300072

出　　处：《安全与环境学报》2014年第2期148-153,共6页Journal of Safety and Environment

摘　　要：在很多地区和行业中,水的有效利用和再生回用受硅沉积的限制。开展了铝电极电絮凝处理不同质量浓度的含硅废水的研究,考察了不同操作条件下出水可溶性硅质量浓度、单位电耗除硅量(SiO2/W)和单位铝耗除硅量(SiO2/Al)的变化特性。结果表明:初始硅质量浓度越高,电絮凝除硅速度越快,SiO2/W和SiO2/Al也越大;极间距减小可增大硅的去除速度,但SiO2/W和SiO2/Al值也变小;当极板间电压变小时,电絮凝除硅速度变小,但SiO2/W和SiO2/Al增大。因此,不同行业应综合去除效果和经济性来选择最佳操作条件。采用DPS(Data Processing System)系统进行数据处理,初步探讨了不同操作因素的相互关系,以及与除硅效果的关系。电极表面SEM图像表明,电絮凝过程中阳极表面不断受到腐蚀,而阴极表面产生了沉淀附着物。The paper has done an investigation on the performance of electrocoagulation to remove silica pollutants from different water sources by using Al-Al electrodes. What we have investigated includes the effects of different factors on the effluent soluble silica concentration, the amount of silica to be removed by the unit power consumption （SiO 2 /W） and the amount of silica that can be removed at the unit aluminum consumption （SiO 2 /Al）. The results indicate that the silica removal at different initial concentrations can be represented by a zero-order kinetics model. Its reaction rate constant should be greater in 5 min than those after the time limit. And, in turn, the higher the initial silica concentration, the higher the removing rate will be and the larger the value of SiO 2 /W and SiO 2 /Al would be. This indicates that better effects and higher economic efficiency could be achieved at high initial silica concentrations. With the decrease of the interelectrode distance, the removing rate tends to be accelerated. Although the removing effect is better, the economic efficiency can be made worse, which implies the reduction of SiO 2 /W and SiO 2 /Al. With the decrease of interelectrode voltage, the removing rate could be slowed down, but the values of SiO 2 /W and SiO 2 /Al is likely to be increased. Therefore, the industry operators should choose the best operating conditions according to their own demands. Moreover, the DPS data processing proves that the regression equation established may have a better fitting effect. It means that the equation could be used as a silica concentration assessment model. And, by analyzing the interaction of the factors and the relation between the said factors and the removing efficiency, a nice correlation can be found between the interelectrode voltage and its distance. They can also be replaced by a new variable to reduce the workloads. Thus, the SEM images of the aluminum electrodes demonstrate that the anode constantly corroded and the cathode are very likely to

关 键 词：环境工程学 可溶性硅 电絮凝 去除效果 经济性 

分 类 号：X523[环境科学与工程—环境工程]