| BHC is an extensive, lasting, fatty soluble and low cost organic chlorine pesticide, it is resistant to high temperature and acid, which has once improved the agricultural production. In the 40~80years last century, almost every country in the world used BHC to protect the agriculture from pest hazard. And in the 50~80years last century, the production amount of BHC is 60% of that of total pesticides. BHC have seriously contaminated the ecological environment due to its long remnant and stability, and because of that our country has banned its production and use in early 80years last century. But restricted by kinds of environment conditions, the degradation speed is very slow. In the environment superintend reports of some area proved that the residue of BHC still can be detected even in high concentration, and it is confirmed one of those widely used POPs.BHC residue has latent danger to the agricultural environment, agricultural and water products, and also the human health. The different framework of BHC is doubted to cancer inducement. γ-BHC can incentive central nerve system, α-BHC,δ-BHC is believed to depress on the central nerve system. γ-BHC,β-BHC are all proved to be endocrine-disrupting hermaphroditism , and can result in dysgenesis or effect on kidney, liver, blood etc. It has reported that BHC can endanger the human health even its concentration is low in water by accumulated through animals and plants or transported by food chains.With the development of society and human science, people pay more and more attention on food safety and environment protection. The BHC pollution case in agricultural and water products occasionally affect the export transaction, resulting in economic loss. In order to enhance the quality of agricultural and water products and ameliorate environment, effective removal of BHC is one of our urgent issue waiting for solve in a period.There is long superintend on the distribution and concentration of BHC. But the removal method study of BHC is comparatively scarce. The current study mostly focuses on biodegradation. Biodegradation, the same as photodegradation, has an active effect on environment remediation. But its degradation ability is limited by the environmental factors, especially in the area with heavy pollution and low temperature. That will result in the low degradation rate and degree, the new pollutants produced with side reaction accompanied by. According to that, it is obvious that we should find a non-biological degradation method.It was expounded by Gillham and O'Hannesin(Cannada) that the metal iron could be used in the in situ remediation of the groundwater. From then, study on the low cost, simple, high effect disposal method-zerovalent metal used to improve the dechlorination of organic chlorine became a research issue. The Fe0-PRB used to remove the water pollutants has gained more and more attention from researchers. Although it was improved a high effect on line chlorineaceous hydrocarbon, there is no report on using in BHC removal.In order to remove the BHC from water and using the discard, this paper refer to the success experience of the PRB technology (it can dechlorine and detoxity on the line hydrocarbon). Considering the defects of it, such as the side reaction and the erosion of the iron and the precipitation produced coated on the surface of the zero valent iron, which may reduce the activity of the iron or result blocking in the barrier, result in the short using period. Different barriers were set up using the cinder, iron, cinder and iron as the reaction material to remove the BHC in water.The conditional experiments were done on the adsorption by cinder and degradation by zerovalent iron on BHC. The results suggest that both the above two have the similar optimal condition in BHC removal. The removal effect is preferably on the asourish, When the diameter diminished or the using amount and reaction time increased, the removal rate enhanced with it. Under the optimal conditions, the cinder's adsorption on BHC can rea...
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