Heavy metal polluted soil restoration planting method

Abstract

The invention relates to the technical field of soil pollution treatment and especially a heavy metal polluted soil restoration planting method. In the method, the planting mode for plants for restoration of the heavy metal polluted soil is completely changed, wherein the plants for restoration are not pre-cultured in a greenhouse and can be directly planted into the heavy metal polluted soil; themethod is free of requirement on concentration of heavy metal ions in the soil and greatly reduces planting difficulty. Heavy metal ions in the lower layer are effectively isolated by covering an asbestos fiber fabric to form an isolation layer; microorganisms are added to soil to reduce the content of metal ions in soil; the soil is watered and then is covered with a film to complex and settle the metal ions; finally, an absorption layer of attapulgite powder can absorb the metal ions for preventing secondary pollution.

Description

Technical field [0001] The invention relates to the technical field of soil pollution control, in particular to a planting method for remediation of heavy metal contaminated soil. Background technique [0002] With the continuous development of the global economy, soil heavy metal pollution has become a major problem facing the global environmental quality. Human activities (mineral mining, metal smelting, domestic wastewater discharge, fertilizer and pesticide use, etc.) have greatly accelerated the biological earth of heavy metals. The chemical cycle causes the heavy metals in the environment to continue to increase, increasing the harm of heavy metals to human health. When the heavy metal entering the environment exceeds its capacity in the environment, heavy metal pollution can occur. Heavy metal pollutants are persistent pollutants, and the harm to the environment and human body is difficult to eliminate. Heavy metals have the characteristics of strong chemical activity, h...

AI Technical Summary

Problems solved by technology

[0004] The above heavy metal repair techniques all have a certain effect on heavy metal repair, but they also have their own shortcomings in practical applications.

Phytoremediation technology has limited types of plants for remediation, and its repair speed is slow, and the retreatment of plants that accumulate a large amount of heavy metals is also the main factor that limits the large-scale promotion of phytoremediation technology; microbial remediation technology generally only adsorbs a single heavy metal. The effect is good, and because the microbial organisms are small, the amount of heavy metals repaired is also small, so this also limits the application of using microorganisms for large-scale on-site repair; the electrodynamic repair technology is still in the experimental research stage, and due to different soil Different physical and chemical properties also have a series of limiting factors in practical application; soil leaching technology is complex and expensive;

[0005] Taking phytoremediation as an example, the existing methods mostly use greenhouses to pre-cultivate the repaired plants. After the seeds grow and develop into seedlings, they are then transplanted to heavy metal-contaminated plots for soil remediation. The cost of transplanting has increased significantly, and it is difficult to achieve mass production. Phytoremediation is currently in the state of experimentation or small-scale trial planting, which is far from idealized restoration

If the seeds are directly sown in heavy metal-contaminated soil, the seeds are difficult to germinate and the germination rate is extremely low. Even if some seeds germinate, the plants are difficult to grow. Because the seeds do not really grow up in the environment of heavy metal ions, it is difficult to exert the heavy metal absorption effect.