The Applied Study Of Lime-Electroflocculation Coupling Technology Deal With High Acid Lead And Zinc Smelting Wastewater

Lead and zinc smelting industry is the high-polluting industries in non-ferrous metal industry,in addition to the lead and zinc smelting process to extract a small amount of metal, also including other non-ferrous metals, generally contain lead, zinc, chromium, copper, arsenic, mercury, fluoride, cyanide and so on. From the smelting process deciding lead and zinc smelting waste water with a large amount of water, many kinds of heavy metal ions, complex and changing water quality, high acidity, and pollution intensity feature. These components into the environment is not easy degradation, but can only stay another form in the environment, not only cause metal wastage of resources,but also affecting the ecological environment and human health. Lead and zinc smelting is an important part of the non-ferrous metal smelting industry, it is a major source of pollutants therefore,to treat lead and zinc smelting industry sewage is particularly important. Currently,the main method to deal with the heavy metals lead and zinc smelting waste water is chemical precipitation, particularly the application of neutralization sedimentation method is more common.Because of the existence of various defects in lime neutralization, such as higher concentration of heavy metal ions, resulting in large amount of slag,dewatering difficulties, produce secondary pollution, and other shortcomings. It is because of these constraints restrict its application in lead and zinc smelting waste water, electricflocculation method has high removal rate of heavy metal, resulting slag is less and can be recycled, good effect of precipitation flocculation dehydration and other advantages. This article is based on this idea, with lime electroflocculation coupled technology dealing with the heavy metals lead and zinc smelting waste water, to technological innovation, for the actual needs of the process in Mengzi Mining Co., Ltd. lime electroflocculation coupling technology has been successfully applied in the technological transformation, the main content is as follows:(1) By the effect of heavy metal removal rate and cost analysis with lime neutralization,electricflocculation,lime neutralization-electricflocculation method,the conclusions are as follows:At pH is10, stirring reaction time is30min, mixing intensity for250r/min, and a certain amount of flocculant FeCl3lime neutralization method reach best experimental conditions. At pH is9, the plate voltage is5V, the plate spacing is0.8cm, the electrolysis time of40minutes, and pH=9aeration treatment, electricflocculation method reach best experimental conditions. At pH is8, the plate voltage is2V, the plate spacing is1.2cm, the electrolysis time of30min neutralization-electricflocculation reach best experimental conditions. Through the three methods under best of the experimental conditions, the comparative analysis of the three ways to get the best treatment effect to get the best treatment of three ways and then comparative analysis, obtained the lime-electroflocculation has the best treatment effect,by contrast three methods of energy consumption, drug costs, equipment costs,obtained the lime electroflocculation method has a distinct cost advantage.(2) Analysis of the coordination chemistry point of view that pH effect on Cu2+, Zn2+, Cd2+, Pb2+hydroxyl ion form and effect of pH on the solubility of Cu(OH)2, Zn(OH)2, Cd(OH)2, Pb(OH)2. Removal mechanism of heavy metal ions from the electrolyticflocculation obtained mainly by charge neutralization effect and the role of the netting effect and the volume swept effect. And a brief analysis of the precipitation sequence of the heavy metal on plate cathode and theoretical analysis.(3) Through transformation of the treatment process in Mengzi Mining Co., Ltd, analysis the treatment effect of before and after the transformation,.through the transformation by lime-electricflocculation process, and follow-up and depth of processing,water can reach the surface water III standard, All the back water for the production.Lime-electricflocculation coupled technology have been successfully used in engineering, to solve practical problems has a great significance.In short, the paper with lime-electroflocculation coupled technology to deal with the heavy metals lead and zinc smelting waste water is an effective approach and by technological transformation has been successfully applied in Mengzi Mining Co., Ltd. Provides a new approach, new tools and new ideas to solve the smelting wastewater treatment.