A repairing agent for repairing hexavalent chromium-contaminated soil and a method for using it to restore hexavalent chromium-contaminated soil

Abstract

The invention proposes a repairing agent for repairing hexavalent chromium-contaminated soil that can reduce hexavalent chromium and block the transformation of trivalent chromium into hexavalent chromium and a method for repairing hexavalent chromium-contaminated soil, including a method for repairing hexavalent chromium The remediation agent for polluted soil comprises the following components by weight percentage: calcium polysulfide solution with a concentration of 29%: 20-35%; curing agent: 10-20%; water: 50-65%; a kind of remediation of hexavalent chromium contaminated soil The method comprises the following steps: S1: Prepare the repairing agent, mix the calcium polysulfide solution with a concentration of 29%, the hardening agent after crushing, and water according to the above ratio and mix evenly to obtain the repairing agent, and put it into the drug storage device for standby; S2: Prepare materials, excavate the soil to be repaired from the polluted land for backup; S3: Initial treatment of restoration, use the soil remediation machine to crush the soil to be repaired and apply drugs during the restoration process; S4: Post-remediation treatment, use the soil remediation machine to During the restoration process, the initial restoration soil was stirred.

Description

technical field [0001] The invention relates to the technical field of soil remediation, and relates to a remediation agent for repairing hexavalent chromium-contaminated soil and a method for using the same to repair hexavalent chromium-contaminated soil. Background technique [0002] Chromium is an element that exists widely in nature. It is mainly divided into trivalent chromium and hexavalent chromium. Most of the chromium in nature exists in the form of trivalent chromium with low toxicity, while hexavalent chromium is produced after industrial activities. , highly toxic and carcinogenic. In recent years, chromium and its compounds have been widely used in production, but due to oversight oversight, improper disposal and other reasons, hexavalent chromium pollution incidents occur frequently, posing a huge threat to the local ecological environment and human health. [0003] The Chinese patent publication number is CN201510159414.3, which discloses the use and restorat...

AI Technical Summary

Problems solved by technology

In recent years, chromium and its compounds have been widely used in production, but due to oversight oversight, improper disposal and other reasons, hexavalent chromium pollution incidents occur frequently, posing a huge threat to the local ecological environment and human health

[0003] The Chinese patent publication number is CN201510159414.3, which discloses the use and restoration method of calcium polysulfide in the restoration of chromium-contaminated soil or groundwater. Calcium sulfide remediation method for chromium-contaminated soil; including soil chromium pollution degree investigation, preparation of calcium polysulfide water agent, determination of dosage ratio of calcium polysulfide water agent, addition of calcium polysulfide water agent, water replenishment, remediation reaction, soil Soil property adjustment after maintenance and remediation; remediation methods for remediating chromium-contaminated groundwater with calcium polysulfide, including arranging injection points and determining the dosage of remediation agents, preparing remediation agents, positioning injection points, injecting calcium polysulfide remediation agents, and adjusting injection point positions and the number of injection points. This method only uses calcium polysulfide to reduce the hexavalent chromium in the soil, but does not consider the possibility that the trivalent chromium in the soil is re-oxidized to hexavalent chromium, and does not consider cutting off the trivalent chromium to hexavalent chromium. transformation pathway, so its remedial effect may be limited to a certain extent, and this method uses in-situ injection to remediate groundwater. For soil contaminated by chromium, in-situ injection cannot make the liquid medicine contact with the soil very well. , the influence of the medicine will also be weakened when the medicine liquid penetrates downward and spreads outward, resulting in the uneven combination of the soil and the medicine liquid, and the repair effect will not increase.

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