The soil leaching remediation technology

Soil leaching means that the solid phase heavy metals in the soil can be transferred to the liquid phase by extractant. The soil containing extractant can be reused after washing with water, then the waste liquid containing heavy metals will be further processed.
The key to the remediation of soil leaching is to find a kind of economical and practical leaching agent, which can effectively remove all kinds of pollutants. It will not destroy the basic physical and chemical properties of the soil and do not cause second pollution. In general, the leaching agent can be divided into inorganic leaching agent, sting agent, surface active agent, compound leaching agent and oxidizing agent. In the actual treatment of contaminated soil, the factors affecting soil leaching and soil remediation technology mainly include soil properties, pollutant properties and process operation conditions.
For example, the soil properties that affect the leaching effect are mainly grain distribution, texture, organic matter content, cation exchange capacity and so on. The nature of the pollutant such as speciation of heavy metals in soil are mainly organic, soluble, exchangeable and residual forms, these forms in accordance with the leaching efficiency in descending order for exchangeable carbonate bound > the Fe Mn oxides bound to organic matter > residue. The heavy metal in the effective form is the key of soil leaching. The process conditions mainly include the stirring strength, the time of leaching, the ratio of solid to liquid and the temperature of the leaching. Selecting the appropriate operating conditions of the leaching process not only helps to remove the pollutants, but also reduces the cost of repair.
The remediation effect of heavy metal contaminated soil is reviewed, and the leaching effect of different eluent on different forms of heavy metals is reviewed. It is pointed out that natural organic acids have the most potential for research because of low ecological toxicity and high degradation. Therefore, the development of efficient and specific washing agents and optimizing process conditions can improve repair efficiency, reduce repair cost and prevent the second pollution.
PARFECT soil stabilization equipment can transfer the soil binder through the air compressor to the mixing head which is mounted on the excavator, and mix with the soil to improve the strength of the foundation.
Learn more about in situ soil stabilization

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