Chromium-contaminated land remediation method

Abstract

The invention discloses a chromium-contaminated land remediation method. The method comprises the following steps: 1, inoculating a sterilized liquid culture medium with a Bacillus sp. strain, performing culturing to obtain a bacterial stock solution, and adding normal saline into the bacterial stock solution to dilute the bacterial stock solution to make the OD600 value be 0.8-1.5; 2, taking anduniformly mixing an aqueous urea solution and an aqueous calcium chloride solution to obtain an adhesive solution; 3, mixing the bacterial solution prepared in step 1 with the adhesive solution prepared in step 2 to obtain a reaction solution; 4, taking chromium-contaminated soil, removing impurities, and air-drying, crushing and sieving the soil; and 5, uniformly pouring the reaction solution prepared in step 3 into the pretreated soil obtained in step 4, and then carrying out constant-temperature culture for 20-40 d. The restoration remediation method can reduce Cr<6+> into Cr<3+>, and the reduction rate can reach 98%.

Description

technical field [0001] The invention belongs to the field of soil remediation, in particular to a bioremediation method for chromium-contaminated soil. Background technique [0002] Hexavalent chromium (Cr 6+ ) is one of the most dangerous pollutants in soil, highly toxic to all living organisms, especially carcinogenic and genotoxic to humans and animals. The hazard and toxicity of Cr depend on its chemical form. In soil, it mainly exists in two oxidation states: Cr 3+ and Cr 6+ . Cr 3+ Relatively stable and low toxicity. On the contrary, Cr 6+ has a ratio of Cr 3+ Higher mutagenicity and toxicity, and Cr 6+ It is more harmful to the soil environment due to its mutagenic and carcinogenic properties. The existing remediation technologies for heavy metal-contaminated soil mainly include physical remediation, chemical remediation and microbial remediation, and both physical remediation and chemical remediation have the disadvantage of high cost, and because microbial...

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Problems solved by technology

On the contrary, Cr 6+ has a ratio of Cr 3+ Higher mutagenicity and toxicity, and Cr 6+ More harmful to the soil environment due to its mutagenic and carcinogenic properties

The existing remediation technologies for heavy metal contaminated soil mainly include physical remediation, chemical remediation and microbial remediation, and both physical remediation and chemical remediation have the disadvantage of high cost, and because microbial remediation technology has low cost, high efficiency, and no secondary pollution and other advantages have received extensive attention in recent years

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