Process of repairing polluted soil by combined use of chemical elution and chemical reduction

Abstract

The invention discloses a process of repairing polluted soil by combined use of chemical elution and chemical reduction. The process comprises the following steps: constructing a spraying site; pre-treating and stacking the polluted soil; arranging a spraying device; preparing an eluting solution in a reagent pond; implementing a spraying process taking acid, alkali and salt as the eluting solution and judging whether the pollutant concentration in a soil lixivium meets a repair target or not; and implementing a spraying process taking a reducer as the eluting solution and judging whether thepollutant concentration in the soil lixivium meets the repair target or not, wherein the spraying process taking water as the eluting solution is executed before the spraying process taking acid, alkali and salt as the eluting solution is executed. By adopting a stacking and spraying process, the process integrates the advantages of a chemical reduction stabilization technology and a chemical elution technology, and solves inevitable problems of the two technologies. The pollutants are reduced more thoroughly by adopting the reducer solution circular spraying process, and meanwhile, pollutioncaused by a lot of pollutants is reduced, use of the reducer is reduced greatly, and the environmental risk is reduced.

Description

technical field [0001] The invention belongs to the field of environmental remediation, and in particular relates to a process for remediating polluted soil by combining chemical leaching and chemical reduction. Background technique [0002] At present, the commonly used remediation technologies for the treatment of hexavalent chromium-contaminated dregs are mainly chemical reduction stabilization technology and chemical leaching technology. For heavily hexavalent chromium-contaminated soils, pure chemical reduction stabilization technology and chemical leaching technology are often difficult to meet the remediation requirements due to the high content of hexavalent chromium, and there are certain risks and hidden dangers. In engineering applications, there are problems such as incomplete reaction and large doses of chemicals added to the reduction and stabilization technology for heavily hexavalent chromium-contaminated dregs. On the one hand, excessive chemicals have cause...

AI Technical Summary

Problems solved by technology

This simple splicing and combination cannot realize the strengths and avoid weaknesses of the two technologies, which makes the process too complicated and there are great difficulties in engineering applications.

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