Soil heavy metal ex-situ remediation method based on molecular combination

Abstract

The invention provides a soil heavy metal passivation agent for remediation of soil contaminated by heavy metals and losing agricultural, industrial and commercial uses and the like. The method includes 1, contaminated soil mining; 2, medicament mixing; 3, soil backfilling; and 4, reuse of the soil. The chemical agent formed by mixing a sulfide, inorganic phosphorus and an alkali undergoes a chemical reaction with the heavy metals, and the heavy metals can be transformed into long-term and stable existing heavy metal sulfides. In addition, low-cost fly ash is added in the soil, so that the heavy metals are stabilized. With the use of the above method, the heavy metals in the soil are reduced to migrate to enter a plant system. The method has the advantages of high efficiency, low cost, strong stability, long-term effectivity with once use, no causing of secondary pollution and the like. The soil heavy metal passivation agent has the characteristics of low cost, simple process, no pollution and good governance effect.

Description

technical field [0001] The invention relates to the technical field of soil heavy metal remediation, and specifically uses chemical agents to react with heavy metals to passivate the activity of heavy metals and make them harmless, thereby realizing the chemical remediation of soil heavy metals. In addition, with the physical effect of the mineral material of fly ash, the effect of reducing the migration of heavy metals in the soil can be achieved. Background technique [0002] Soil heavy metal pollution has the characteristics of long residence time, strong pollution concealment, inability to be degraded by microorganisms, and can accumulate in organisms through the food chain, and eventually accumulate in the human body to endanger human health. Therefore, soil heavy metal pollution has attracted increasing attention. . Therefore, how to effectively control, control and restore soil heavy metal pollution has become the primary task of my country's current soil ecological ...

AI Technical Summary

Problems solved by technology

[0004] The purpose of adding chemicals is to change the physical and chemical properties of the soil, and through the adsorption, precipitation or co-precipitation of heavy metals, the existing state of heavy metals in the soil is changed, thereby reducing their bioavailability and mobility.