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The natural concentration of heavy metals in general are widespread in nature, however, due to human exploitation of heavy metals, smelting, processing and manufacturing business activity increased, a lot of heavy metals such as lead, mercury, cadmium, cobalt, and so on went into the atmosphere, water, soil environment, causing serious environmental pollution. Heavy metals exist in various chemicals or chemical form. When they are putted into the environment or ecological system, they will be retained, accumulation and transfer. It makes harmful. If the heavy metals discharge with the wastewater, even the concentration become lower, it also can accumulation in the algae and sediment and adsorb by fish and shellfish surface, produce the food chain enrichment, Thus causing public nuisance.Removing iron and manganese from ground water has been studied for many years, largely through biological filtration process, and this subject tends to use chemicals to remove, the advantage is that the process is so quick.This topic based on Huayuan county surface water has been polluted by manganese, lead, zinc. Beaker Cup tank experiment is planned to do in the laboratory. The concentration of heavy metals above and water turbidity are the scale index. Research PAC, PFS, aluminum chloride, ferric chloride, alum these coagulants and sodium sulfide practical application.Kaolin as a simulation of the turbidity of the water additives, it is useful for the removal of heavy metal ions, reference to many scholars studies of kaolin, kaolin can be seen as water samples in the flocculant.In the aspect of removal of turbidity , PAC and alum are better than others, PFS and other molysite removal rate is little lower than 1 NTU, and the treated water samples has a higher color point.if it hasn’t sodium sulfide in the course of removing the heavy metal ions, but take the coagulants in PH 6~9, only 10 percent removal rate to 20 percent, basically no effect.The coagulation experiments effect factors were Identified as the size and amount coagulant, PH value, temperature, sodium sulfide and amount by orthogonal experiments. By comparing the experiment results ,take a lot of study on the removal effects of zinc, manganese, lead, separately and comprehensivly.Through PDA dynamic monitoring of access attain the time floc come into being, according to PDA curve of floc size coagulation time with the trend of changes in order to determine the best time of flocculation.
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