Method for repairing cadmium-polluted farmland soil

Abstract

The invention discloses a method for repairing cadmium-polluted farmland soil. The method comprises the following steps: selecting a cadmium-polluted farmland soil region, arranging soil ridges on the periphery of the region, and compacting and covering the peripheries of the soil regions by using waterproof films; after adding clear water which submerges the surface layer of the soil, turning over the soil; uniformly sprinkling a drip washing agent in the soil which is turned over, and fully stirring evenly, standing and discharging; and adding clear water in the soil, carrying out drip washing for 1-3 times, and fully stirring evenly, standing and discharging; and adding a conditioning agent in the soil, fully stirring evenly, standing, and moisturizing and maintaining to obtain the repaired farmland soil. The whole treatment process is simple, the cost is low, the period is short, the structure and the character of the soil are not affected, normal farming and planting of the land are not obstructed, heavy metals can be removed perpetually, and therefore, the method can be widely used for repairing the cadmium-polluted farmland soil.

Description

technical field [0001] The invention belongs to the technical field of remediation of farmland heavy metal polluted soil, and in particular relates to a method for remediation of cadmium-contaminated farmland soil. Background technique [0002] There are two sources of soil heavy metals, man-made and natural factors, among which man-made factors are the biggest cause of soil heavy metal pollution. Most of the heavy metal pollutants in the soil remain in the top layer of the soil, and it is difficult to move to the lower layer of the soil, and the topsoil is the place where animals and plants live. The heavy metals entering the soil are not easy to degrade and have concealment, and their toxicity will affect crops The growth of soil can also cause changes in soil structure and function. Therefore, if the soil is polluted by heavy metals, if it is not repaired in time, it will cause pollution of groundwater and crops, which will cause great harm to human health. [0003] In ...

AI Technical Summary

Problems solved by technology

The disadvantage of this method is that the EDTA used is an artificial chelating agent, which is expensive and prone to secondary pollution

[0008] Chinese patent CN105618472A discloses a method for permanently removing effective heavy metals in heavy metal-contaminated soil. The method is a nanoporous ceramic composite material and citric acid is added as a heavy metal ion dissolution agent during the plowing process to repair cadmium-contaminated farmland. The disadvantages of this method The reason is that nanomaterials are not suitable for large-scale use in practical applications, and the soil structure will be damaged if repeated times are too many. In addition, the pH value of the soil will be acidic if the farmland soil is not treated after using citric acid as the dissolution agent, which will reduce the use value of the soil for farming.

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