A Comprehensive Restoration Method for Severely Contaminated Land

Abstract

The invention discloses a comprehensive remediation method for seriously polluted land. The comprehensive remediation method comprises the following steps: digging up soil from the seriously polluted land; putting the soil into a treatment tank; mixing the soil with a remediator, and uniformly stirring the soil and the remediator to obtain a mixture I; carrying out a reaction for 4 to 5 hours; carrying out mud-water separation after the reaction, so as to separate out precipitate of heavy metal, repeating the steps for 5 to 10 times; adding molasses and bean cake powder; uniformly stirring to obtain a mixture II; adjusting the moisture content of the mixture II to be 20 to 40 percent; carrying out air isolated curing for 1 month at 20 to 30 DEG C to obtain a semi-finished soil product; putting the semi-finished soil product into the seriously polluted land; applying an organic fertilizer; putting earthworms for cultivation; watering every day to ensure that the moisture content is 60 to 70 percent; collecting the earthworms after half a month; planting sisal and tall fescue in the soil, wherein each planting season lasts for three months, and after planting in each planting season, plants are collected together with roots, the soil is turned again for planting, and the organic fertilizer is added for further planting.

Description

technical field [0001] The invention belongs to the technical field of environmental protection, and in particular relates to a comprehensive restoration method for heavily polluted land. Background technique [0002] Soil is the fertile and loose surface of the earth that can grow plants. It is a necessary means of production for human survival and development, and it is also the most basic, important, and irreplaceable natural resource for human society. Therefore, the protection of soil environment has attracted attention. extensive attention. [0003] According to the types of pollutants, polluted soil can be divided into soil polluted by organic matter and soil polluted by inorganic matter. Soil organic pollutants refer to organic compounds that enter the soil environment and cause pollution, mainly including petroleum, benzene series, pesticides, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), etc. The industries involved in the discharge o...

AI Technical Summary

Problems solved by technology

However, for the contaminated soil containing 5-ring and more than 5-ring PAHs, the chemical oxidation technology has poor remediation effect.

[0005] The existing heavy metal contaminated soil remediation technologies mainly include chemical methods (chemical immobilization and stabilization, chemical reduction), isolation and embedding methods, thermal separation methods, electrical remediation methods, microbial remediation methods, phytoremediation methods, adsorption methods and cleaning methods. The chemical method changes the nature of the soil, the treatment cost is high, and there is secondary pollution

In short, the current soil remediation technology generally has the defects of high cost, serious secondary pollution, complicated operation, and long repair period; the isolation and embedding method only isolates heavy metals, and there is still potential danger to the soil ecology; It is relatively immature; the thermal separation method is not suitable for on-site operation, the treatment cost is high, and the scope of application is narrow; the carrier used by the microbial remediation method is a living microorganism, and the discontinuous distribution of pollutants will block the movement of microorganisms, so the treatment period is long, and it is different from the indigenous Microorganisms compete for organic nutrients as substrates, and are prone to lose activity; phytoremediation has a long repair period (decades or even hundreds of years), and there are problems in the subsequent treatment of plants; electric remediation is only suitable for small areas of pollution, and it is difficult to operate on site; The adsorption method has the disadvantages of easy saturation, high cost, and low efficiency; compared with the other methods mentioned above, the cleaning method has the advantages of short cycle and low cost, but when using chemical reagents, it is easy to affect the soil environment and cause secondary pollution

[0006] Although the above-mentioned methods in the prior art have their advantages, their functions are relatively single and have certain limitations. They cannot deal with complicated and heavily polluted land, such as land polluted by both organic and inorganic substances.