Physical remediation technology of contaminated soil

Physical soil remediation refers to the removal or separation of pollutants (especially organic pollutants) from soil by various physical processes. Heat treatment technology is mainly applied in physical organic contaminated soil remediation technology of industrial enterprises, including thermal desorption, microwave heating and steam extraction technology which has been applied to the repair of benzene, polycyclic aromatic hydrocarbons, PCBs and dioxin contaminated soil.

1.Thermal desorption technique
Thermal desorption is a direct or indirect heat exchange process to heat organic pollutants in soil to a high enough temperature to evaporate and separate from soil medium. Thermal desorption technology has the advantages of wide range, pollutant treatment equipment can be mobile, after the restoration of soil can be used, especially for organchlorine like PCBs, approach of non oxidative combustion can significantly reduce the generation of dioxin. At present, the western countries have the soil thermal desorption technology engineering, widely used for site remediation of organic contaminated soil in highly pollution or in situ soil remediation, but such related equipment is expensive, the desorption time is too long, the high cost of processing problems have not been solved which limits the application of thermal desorption technology in remediation of persistent organic contaminated soil. The development of contaminated soils before treatment and desorption gas treatment technology, process optimization and development of automation equipment is related to the common direction.

2.Steam extraction technology
Soil vapor extraction (SVE) technology is an in situ remediation technique for removal of volatile organic compounds (VOCs) from soil. It injected fresh air into the contaminated area through the injection well, and produced negative pressure through the vacuum pump. When the air passed through the contaminated area, it desorbed and entrained the VOCs in the soil pore and flowed back to the ground through the extraction well; The extracted gas can be discharged into the atmosphere or re injected into the underground for recycling by means of activated carbon adsorption and biological treatment. SVE has the advantages of low cost, strong operability, standard equipment, wide range of organic matter treatment, no damage to soil structure and no secondary pollution. The removal rate of petroleum hydrocarbons such as benzene and other light components can be up to 90%. Research on soil VOCs multicomponent mass transfer mechanism, accurate calculation of gas flow and velocity, the smearing effect to solve the gas in the extraction process, reduce exhaust purification cost, improve pollutant removal efficiency, is the need to optimize the extraction technology of soil vapor.




PARFECT soil remediation equipment can inject the chemical reagents 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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Treatment of soft soil foundation by high pressure injection method

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What is soil remediation

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