Method for combining microorganisms with curing agent to remediate heavy metal contaminated soil

Abstract

The invention provides a method for combining microorganisms with a curing agent to remediate heavy metal contaminated soil. The method comprises the following steps: mixing magnetotactic bacteria with heavy metal contaminated soil, irrigating the heavy metal contaminated soil which is mixed with the magnetotactic bacteria, setting magnetic fields on the heavy metal contaminated soil, collecting the heavy metal contaminated soil containing the magnetotactic bacteria, leaching the heavy metal contaminated soil, and re-filling the heavy metal contaminated soil; embedding a porous hard plastic capsule containing the curing agent into the heavy metal contaminated soil subjected to adsorption treatment by the magnetotactic bacteria, culturing the porous hard plastic capsule for 20-25 days, then, taking back the embedded porous hard plastic capsule; and repeating the steps in a circulating mode until content of the heavy metals in the soil reaches the safety standards. The method for combining microorganisms with a curing agent to remediate heavy metal contaminated soil disclosed by the invention belongs to in-situ remediation, is simple to operate, low in cost, good in remediation effect, capable of directly removing heavy metal ions without causing secondary pollution on the soil, and suitable for large-area contaminated soil governance.

Description

technical field [0001] The invention belongs to the field of contaminated soil treatment, in particular to a method for jointly repairing heavy metal-contaminated soil by microorganisms and curing agents. Background technique [0002] Soil pollution is caused by excessive harmful substances contained in the soil, exceeding the self-purification capacity of the soil, which causes changes in the composition, structure and function of the soil. Harmful substances gradually accumulate in the soil, through "soil→plant→human body", Or it can be indirectly absorbed by the human body through "soil → water → human body", reaching the level of endangering human health. Soil heavy metal pollution mainly includes mercury (Hg), cadmium (Cd), lead (Pb), chromium (Cr) and metalloid arsenic (As) with significant biological toxicity, as well as zinc (Zn), copper ( Cu), nickel (Ni) and other elements, heavy metal pollution elements have poor mobility in the soil, long residence time, can onl...

AI Technical Summary

Problems solved by technology

Due to the convenient operation and quick effect, it plays an irreplaceable role in the process of polluted soil treatment; at present, the main curing agents are cement, lime, fly ash, etc., and their application range is narrow, the cost is high, and some curing agents themselves There are secondary pollution, such as fly ash, the long-term curing effect of the curing agent is unstable, etc.

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