一种新型重度铬污染土壤修复技术OA

The soil chromium pollution of retired chromium chemical enterprises in China is serious,and the hexavalent chromium concentration in some soils can be as high as 103～104 mg·kg-1,which has a bad effect on plant growth and human ac-tivities.The commonly used remediation methods of chromium contaminated soil include reduction remediation technology,bioreme-diation technology,acid leaching-reduction combined remediation technology,leaching and reduction of hexavalent chromium in soil with dilute acid solution and reducing agent.However,the effect of acid solution on the dissolution of hexavalent chromium is limited,and it is easy to cause secondary environmental problems such as soil erosion.The remediation process of leaching and reduction of heavy chromium contaminated soil under alkaline condition can effectively solve the secondary environmental problems of acid leaching,such as soil dissolution,calcium loss,significant increase of salt content and excessive leaching concentration of other heavy metals,and this technology can significantly improve the extraction and reduction efficiency of difficult to extract hex-avalent chromium.This study forms an economical and feasible technical route for remediation of chromium contaminated soil.