Curing agent for restoring heavy metal contaminated soil

Abstract

The invention relates to the technical field of contaminated soil treatment, in particular to a curing agent for restoring heavy metal contaminated soil. The curing agent comprises the following components in percentage by weight: 25 to 40 percent of cement, 40 to 65 percent of high-adsorbability clay mineral and 10 to 20 percent of quicklime. The curing agent has the advantages of no risk of secondary pollution when heavy metal ions are fixed by the high-adsorbability clay mineral and no obvious change of original soil property. The components of the high-adsorbability clay mineral are close to those of the original powdered clay, so great damage to a soil structure by the cement and the quicklime is avoided. Therefore, the curing agent also has the advantages of obvious effect of restoring heavy metal plane source contaminated agricultural land and good social, economic and environmental benefits.

Description

technical field [0001] The invention relates to the technical field of contaminated soil treatment, in particular to a curing agent for repairing soil polluted by heavy metals. Background technique [0002] At present, the remediation technologies for heavy metal-contaminated soil mainly include: replacement and filling method, biological remediation method, chemical fixation method, electrodynamic remediation method, etc. Among them, the replacement method is only suitable for small areas and heavily polluted soil; the bioremediation method has the advantages of low treatment cost and high cleaning level, but it takes a long time for restoration and is greatly limited by the type of pollutants; The repair method has different effects in different soil types, or even has the opposite effect, and the cost is high and the operation equipment is complicated, which is not conducive to large-scale application. The solidification and remediation technology of heavy metal polluted...

AI Technical Summary

Problems solved by technology

Its main disadvantages are: the application area is narrow, that is, some curing agents are effective for some heavy metal ions but not effective for others; the cost is high; some curing agents themselves have secondary pollution, such as fly ash; the curing agent is cured for a long time The effect is unstable. For example, the organic curing agent is easy to decompose after two or three years, so the fixed heavy metal ions may be released again.

[0004] Moreover, the above-mentioned curing agent is used to treat polluted soil. Although the polluted soil after treatment can be used as filling materials such as foundations and roadbeds, there is often no such construction work around the polluted soil, and after adding curing agents such as cement and lime Vegetation cannot be planted on the polluted soil, it can only be buried deep in the ground