A composition for remediation of polluted soil at relocation site of electroplating enterprises and its application

Abstract

The invention provides a composition for restoration of contaminated soil in an electroplating enterprise relocation site and an application thereof. The composition comprises the following componentsby mass: a component A, which comprises 1 to 20 wt.% of soluble ferrous salt and 80 to 99 wt.% of glucose; a component B, which comprises 100 wt.% of soluble aluminum salt; and a component C, which comprises 100 wt.% of quicklime. According to the invention, rapid and highly-efficient zinc-chromium passivation effects are achieved; in the concrete process of an experiment, with addition of the component C as a restoration starting point, the extraction concentrations of zinc and chromium with an acetic acid extraction method are respectively reduced by 75% and 83% in one day; the hydrotalcite-like mineral formation proportion of zinc in the contaminated soil is 63% or above; when the time of treatment is 30 days, the hydrotalcite-like mineral formation proportion of the zinc in soil is even increased to 87%; and according to the chemical properties of hydrotalcite, the hydrotalcite can stably exist in a pH value range of 2 to 14, so the purpose of long-term passivation of heavy metalsin the soil can be achieved.

Description

technical field [0001] The invention belongs to the technical field of remediation of heavy metal-contaminated soil, and in particular relates to a composition for remediation of contaminated soil at relocation sites of electroplating enterprises and an application thereof. Background technique [0002] According to the "National Soil Pollution Survey Bulletin" issued by the Ministry of Environmental Protection in 2014, the overall soil environment in my country is not optimistic, with a total pollution exceeding the standard rate of 16.1%. % and 1.1%, both of which are among the eight most widely distributed inorganic pollutants. It is especially worth noting that the soil environmental problems of industrial and mining wastelands are prominent. With the implementation of policies such as "retire two to enter three", "retreat cities and enter parks", the development of urbanization, the adjustment of urban layout planning and the upgrading of industrial structure, a large nu...

AI Technical Summary

Problems solved by technology

[0006] 1. The addition of some passivating agents leads to secondary pollution of the ecological environment. For example, apatite will cause soil acidification, increase the activity of arsenic ions, and release a large amount of phosphorus at the same time, which may lead to the risk of eutrophication of water bodies. ;

[0007] 2. The passivation effect of some passivators lacks long-term stability, such as sulfide, lime, etc., and the short-term passivation effect is very good, but under the condition of soil oxidation-reduction potential or pH change, the insoluble precipitation formed by heavy metals will dissolve again;

[0008] 3. A single agent can often only repair a single heavy metal pollution in the soil, and soil heavy metal pollution is generally the coexistence of multiple heavy metals, and the effect of a single repair cannot meet the demand;

[0009] 4. The composition and physical and chemical properties of the soil are extremely complex, and many heavy metal ions are closely chelated with the soil, which affects the interaction between passivators and heavy metals

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