Method for chromium-contaminated soil remediation by mirabilis jalapa

Abstract

The invention discloses a method for chromium-contaminated soil remediation by mirabilis jalapa. The method includes steps: (1) selecting mirabilis jalapa seedlings, and cutting into chromium-contaminated soil, or directly sowing mirabilis jalapa seeds into the chromium-contaminated soil; (2) adding ethylenediamine tetraacetic acid into the chromium-contaminated soil to serve as a reinforcing agent; (3) integrally removing mature mirabilis jalapa from the chromium-contaminated soil, and planting a second batch of mirabilis jalapa; (4) repeating the steps (1)-(3) until the chromium content of the chromium-contaminated soil reaches an environmental safety level. The method has advantages of low cost, low engineering quantity, low technical requirement and the like; owing to green remediation, additional treatment of obtained mirabilis jalapa plants is avoided, secondary pollution is prevented, damages of soil structure and original physicochemical properties in a remediation process are avoided, problems of soil degradation, productivity decline and the like caused by heavy metal pollution can be improved beneficially, and biological diversity of soil can be recovered and improved beneficially.

Description

technical field [0001] The invention belongs to the field of remediation of soil polluted by heavy metals, and more specifically relates to a method for remediating chromium-contaminated soil by using Mirabilis mirabilis. Background technique [0002] Chromium is a trace element necessary for humans and animals, but if it contains too much chromium, it is harmful to humans, animals and plants. In 2005, chromium slag pollution control was listed as a key project in the national "Eleventh Five-Year Plan". The tanning industry produces a large amount of chromium-containing sludge due to its production process, which is one of the main sources of chromium-contaminated soil. At present, less than 20% of enterprises in my country's tanning industry have achieved complete wastewater treatment, resulting in the deposition of 2-40.0g / kg of wastewater metal chromium in the sludge. Most of these sludges are placed around farmland in the suburbs, of which nearly 10% The sludge applied ...

AI Technical Summary

Problems solved by technology

At present, less than 20% of enterprises in my country's tanning industry have achieved complete wastewater treatment, resulting in the deposition of 2-40.0g / kg of wastewater metal chromium in the sludge. Most of these sludges are placed around farmland in the suburbs, of which nearly 10% The sludge was applied to farmland, which further aggravated the secondary pollution of chromium to farmland soil

[0003] The traditional chromium pollution remediation technology is costly, needs to disturb the soil structure, and can only treat small areas of pollution

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