a)Room Temperature Desorption Technology:
The technology makes use of the feature that organic pollutants in soil are volatile easily at room temperatures, has polluted soil stirred strongly with soil analyzing mechanical devices (such as turners, soil improving machines and screening machines) at room temperatures, mixes room temperature desorption agents in polluted soil if necessary so as to increase the void ratio of the soil and make volatile organic compounds adsorbing in polluted soil granules desorb and volatilize, finally collects and removes them with ventilating pipelines and tailing processing systems equipped in the closed workshops.
Relate patent: 1) A VOCs Tail Gas Treatment Unit and A Method Thereof 201610222531.4; 2) Thermal Desorption Integrated Treatment Method and Device.
The technology makes use of the feature that organic pollutants in soil are volatile easily at room temperatures, has polluted soil stirred strongly with soil analyzing mechanical devices (such as turners, soil improving machines and screening machines) at room temperatures, mixes room temperature desorption agents in polluted soil if necessary so as to increase the void ratio of the soil and make volatile organic compounds adsorbing in polluted soil granules desorb and volatilize, finally collects and removes them with ventilating pipelines and tailing processing systems equipped in the closed workshops.
Relate patent: 1) A VOCs Tail Gas Treatment Unit and A Method Thereof 201610222531.4; 2) Thermal Desorption Integrated Treatment Method and Device.
b)Soil Gas Phase Extraction Technology:
This technology uses vacuum pumps to produce a negative pressure; when the air flow through the polluted area, it will desorb and carry away volatile and semi-volatile organic pollutants in the soil gaps; then the extraction well will finally collect and treat these pollutants, thus achieving the aim of purifying soil in the vadose zone. Sometimes, gas-injection wells can be set during extraction and inject air in the soil manually.
This technology uses vacuum pumps to produce a negative pressure; when the air flow through the polluted area, it will desorb and carry away volatile and semi-volatile organic pollutants in the soil gaps; then the extraction well will finally collect and treat these pollutants, thus achieving the aim of purifying soil in the vadose zone. Sometimes, gas-injection wells can be set during extraction and inject air in the soil manually.
c)Chemical Oxidation/Reduction Technology:
Inject oxidizing agents or reducing agents in soil or underground polluted regions, and make pollutants in the soil or groundwater transform into non-toxic or relatively less toxic matters through oxidation or reduction. Common oxidants include permanganate, hydrogen peroxide, Fenton's reagent, persulfates and ozone. Common reducing agents include hydrogen sulfide, sodium dithionite, sodium bisulfite, ferrous sulfate, calcium polysulfide, iron divalent, zero-valent iron, etc.
(Related patent: In-situ Oxidation Agent and In-situ Oxidation Remediation Method of Contaminated Soil).
Inject oxidizing agents or reducing agents in soil or underground polluted regions, and make pollutants in the soil or groundwater transform into non-toxic or relatively less toxic matters through oxidation or reduction. Common oxidants include permanganate, hydrogen peroxide, Fenton's reagent, persulfates and ozone. Common reducing agents include hydrogen sulfide, sodium dithionite, sodium bisulfite, ferrous sulfate, calcium polysulfide, iron divalent, zero-valent iron, etc.
(Related patent: In-situ Oxidation Agent and In-situ Oxidation Remediation Method of Contaminated Soil).