Fertilizer for Cr (VI) polluted soil remediation and improvement and preparation method of fertilizer

Abstract

The invention discloses fertilizer for Cr (VI) polluted soil remediation and improvement and a preparation method of the fertilizer. The preparation method of the fertilizer comprises the following steps: spraying an EM microbial agent to the surfaces of bagasse and pig manures, then uniformly mixing the bagasse with the pig manures, and composting the mixture to obtain a cured material; adding anOneida silva microbial agent, the EM microbial agent and a desulfovibrio microbial agent into the cured material, uniformly mixing the microbial agents with the cured material, and composting the mixture to obtain a microbial compound; and mixing ferrous sulfate, modified coal ash, ground calcium carbonate and the microbial compound, and granulating the mixture to obtain the fertilizer. The fertilizer can improve the soil structure, improve the soil fertility and remediate and improve a microecological structure of the soil when effectively remediating chromium pollution, finally remetiates and improves the chromium-contaminated soil, and restores the ecological functions.

Description

technical field [0001] The invention relates to a fertilizer, in particular to a fertilizer for remediation and improvement of Cr(VI) polluted soil and a preparation method thereof, belonging to the technical field of remediation of heavy metal polluted soil. Background technique [0002] Cr(VI) is highly toxic and is one of the 129 key pollutants recognized by the US Environmental Protection Organization, and one of the eight most harmful chemicals to the human body. Cr(VI) in soil is teratogenic and carcinogenic, destroys soil micro-ecology and soil structure, and reduces soil fertility and ecological functions. [0003] The remediation methods of Cr(VI) contaminated soil mainly include leaching method, biological remediation method, electrokinetic remediation method, reduction stabilization method and so on. Wherein the leaching method is only applicable to soils with large permeability coefficients such as sandy soil, which is prone to secondary pollution, high cost, an...

AI Technical Summary

Problems solved by technology

Phytoremediation of Cr(VI)-contaminated soil mainly uses enrichment plants such as mustard, ramie, Lishihe and paspalum to extract and enrich Cr(VI) in the soil. This technology is low in repair cost, environmentally friendly, and improves soil ecological performance. However, the remediation period is long, it is difficult to realize short-term rapid remediation, and it is difficult to remediate heavy Cr(VI) contaminated soils. For example, Chinese patent (CN106391678A) discloses a phytoremediation method for chromium-contaminated soils. Corn, etc. are planted on the polluted land, planted twice, and the first time is 2 to 6 months later, and the second time is planted. This method is to plant trees on the chromium-contaminated soil, and use the lawn with dense root system, corn and other crops. Through photosynthesis and water absorption by its rhizomes, hexavalent chromium in the soil migrates to plants, achieving the purpose of remediating chromium-contaminated soil

The solidification / stabilization method is currently a cost-effective technology for remediating Cr(VI)-contaminated soil. This method usually uses chemical reducing agents such as ferrous salts as the basic agent to reduce and stabilize Cr(VI). The remediation period is short and the effect is good. Large-scale application, but the solidification and stabilization will easily destroy the fertility and microbial habitat of Cr(VI) polluted soil, destroy the soil structure, and basically lose the ecological function of the soil after restoration; Chemical agent and application thereof, said stabilizer agent includes cement, sulfide, flocculant and pH regulator etc., this agent can significantly reduce the leaching concentration of chromium in soil

These methods have their own advantages and disadvantages, but while remediating Cr(VI) polluted soil, improving soil fertility and micro-ecological environment, improving soil structure, and finally improving soil ecological function methods and agents are rarely reported.

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