Restoration method for heavy metal polluted soil of ore districts

Abstract

The invention provides a restoration method for heavy metal polluted soil of ore districts. Castor-oil plants are planted, biological carbon base fertilizer is applied into the heavy metal polluted soil of the ore districts at the same time, the biological carbon base fertilizer is mixed evenly and seasoning is conducted; biological carbon base fertilizer is applied into the heavy metal polluted soil again after the seasoning, and seasoning is conducted again; earthworms are placed in the heavy metal polluted soil to be bred after the seasoning; after the earthworms are introduced to the soil normally, willows are planted and biological carbon base fertilizer is applied into the soil at the same time, and the willows are removed overall after a certain period; and the steps are executed circularly and repeatedly until the content of heavy metal in the soil is up to the safety standard. According to the restoration method for the heavy metal polluted soil of the ore districts, the restoration effect for the heavy metal soil of the ore districts is obvious; the restoration period is short, and secondary pollution to the soil is avoided.

Description

technical field [0001] The invention relates to the field of contaminated soil treatment, in particular to a repair method for heavy metal polluted soil in mining areas. Background technique [0002] In recent years, environmental pollution and ecological damage have become increasingly serious, seriously affecting human health and survival, among which heavy metal elements have particularly serious environmental pollution and damage effects, especially Pb, Cd, Hg, Cu and their compound pollution are the most prominent, especially in some economically developed regions. Heavy metals are a kind of highly toxic inorganic pollutants. Their particularity is that they cannot be degraded by soil microorganisms and can be completely eliminated from the environment. When they accumulate in the soil to a certain extent, they will cause toxicity and damage to the soil-plant system. The destructive effect has great harm to the growth, yield and quality of crops, especially they can al...

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Problems solved by technology

The isolation and embedding method has the lowest treatment cost, but only isolates the heavy metals, and there are still potential risks to the soil ecology in the mining area; the electrochemical method is relatively immature, and is only suitable for small-area pollution, and the on-site operation is difficult; the heat treatment method is not suitable for on-site operation , the treatment cost is high and the scope of application is narrow; the chemical method is easy to change the properties of the soil and cause secondary pollution; the use of hyperaccumulative plants for phytoremediation is currently a research hotspot in the treatment of heavy metal contaminated soil, but there are still some shortcomings in this project. In particular, most of the plants that hyperaccumulate heavy metals generally have short plants, slow growth, and low biomass, so the restoration efficiency is low and the time required is long, and it is generally difficult for hyperaccumulative plants to grow directly in mining soils that are seriously polluted by heavy metals; microbial restoration The carrier used by the method is living microorganisms, and the discontinuous distribution of pollutants will block the movement of microorganisms, so the treatment cycle is long, and it competes with indigenous microorganisms for organic nutrients, and it is easy to lose activity

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