用电凝聚装置去除废水中重金属离子

用一种新型电极结构的电凝聚装置,对废水中的重金属离子进行了去除实验研究.并对影响重金属离子去除率的各种因素进行了分析.结果表明,使用该装置在适当的实验条件下,可以有效去除废水中的Zn2+、Cd+2、Pb+2、Hg2+和Cu+2,使之达到达标排放或回用水平.该装置具有结构简单,自动化程度高,操作简便,占地面积小,污泥产量小的特点.

A NEWLY-INNOVATED ELECTRO-COAGULATION DEVICE FOR REMOVING HEAVY METAL FROM SEWAGE WATER

The present paper has introduced a new electro-coagulation device with a special electrode for removing heavy metal from the sewage water. Since the heavy metal ion in the water is considered as highly toxic, the authors believe it would be of great environmental and industrial value to develop an effective device or method for the above purpose. Compared with the ordinary electro-coagulation one, the present device has such advantages as being highly automatic in control, convenient in use, small in the volume of sludge left over, etc. The device introduced by the authors has succeeded in avoiding such shortages as electrode-passivation and short circuit. Testing and experiments have also been done with the device, which shows that it can remove two kinds of water samples highly efficiently. The present paper has also analyzed all the influential factors with the removal rate. They are pH value, voltage, conductance and reaction time. As is shown in the paper, the optimal pH working scale of this device is 6.5~8.5. Under the condition given, voltage, conductance rate and reaction time can be adjusted automatically according to the actual demand of the outflow standard. The testing demonstrates that the removing rate of Zn 2+ , Cd 2+ , Pb 2+ , Hg 2+ and Cu 2+ is over 95% while the wastewater removed by the device can reach the level of recycling or discharge. In addition,the present paper has also put forward three conclusions in the end. First, the removal rate can reach more than 95% both for removing single metals and for removing many kinds of heavy metal mixed together. Second, with the device used, waste water treatment cost is only 0.51 yuan per ton, not higher than the other methods. Third, the device innovated raised the automatic control to the pH of inflow, the distance between the two electrodes and the quality of outflow. Therefore, it can be concluded that the device will enjoy a better share in the future.