Chemical Remediation Of Heavy Metal Contaminated Soil In Da Maoping Copper Mine

Because of the exploitation of mineral resources, the heavy metal pollution of land in our country is large, the degree is serious, and the reclamation rate is low. The treatment of heavy metal polluted soil in mining area is urgent, and the relevant research in this field has become the key, difficult and hot spot of soil science, environmental science and ecology. Chemical modifier for the repair and the results from the current international research hot chemical improvement agent point of view, select the lime, calcium magnesium phosphate fertilizer,bentonite soil biological carbon(charcoal) four fixing agent, each are respectively arranged three concentration gradient is applied to the area, and the cultivation of wheat, through successively two times sampling for the determination of the soil and wheat in Cu, Zn, Pb, Cd and effective state content changes, the fixing agent of the mining area of heavy metal pollution soil repair capacity, screening out the optimum application concentration promotes the repair effect, promote the heavy metal contaminated soil remediation technology specification and implementation, the formation has the actual application value of mining area of heavy metal contaminated soil remediation system. The following conclusions are drawn in the experiment:(1) Lime, calcium magnesium phosphate fertilizer, bentonite and charcoal four amendments on soil pollution of Cu, Zn, Pb, Cd has certain repair effect, which the lime overall repair the best results.(2) For weak acid Da Mao Ping diggings of heavy metal contaminated soils, limestone and calcium magnesium phosphate is in good repair agent, can improve the soil pH, for exchangeable heavy metals with good fixing effect, which high dose of limestone processing to reduce the effectiveness of Cu, Zn, Pb and Cd respectively reach 62.73%, 59.97%, 71.20%and 34.38%. The high dosage of bamboo charcoal can significantly reduce the content of Pb,Zn, Cd and Cu in the soil. Overall, four amendments on soil exchange to reduce the sorting effect metals content: Limestone > calcium magnesium phosphate > bamboo > bentonite for the in situ remediation of Ningqiang County Soil Contaminated by heavy metals mining area summed up a set of has the reference value to the promotion and the experience.(3) The content of Cu, Zn and, Zn content in wheat plants were basically consistent with the change of the content of and Cu in the soil after the application of the amendments in thesoil. The results show that the modified agent remediation of the contaminated soil in mining areas has repair effect, high rates of lime dosage can reduce plant to exchange absorption of heavy metals in the state, in the practice of the mining area of soil remediation has great application potential.(4) From reduced plant absorption of heavy metal is concerned, limestone, calcium magnesium phosphate fertilizer and bamboo charcoal can effectively reduce the content of Cu and Zn in wheat straw and grain, reduce the migration of heavy metal to plants of the risk, to ensure plays a certain role in the quality and safety of agricultural products, and calcium magnesium phosphate can be for crops provide nutrient elements P, Si, Ca, Mg, reduce fertilizer additional application, improve the soil pH, on the environment has good effect, has a broad application prospect.