Remediation technique | Technique principle | Characteristics |
---|---|---|
Ex situ | ||
Pump and treatment | Groundwater is extracted and sent to the sewage treatment system for decontamination | Suitable for the treatment of soluble pollutants |
Excavation method | The method of soil excavation can be used to treat and remediate the polluted groundwater | Only suitable for a small range of groundwater pollution |
In situ | ||
Bioremediation | Utilize microorganisms to transform contaminants into less harmful daughter-products | Long processing time, need the integrated application |
Air sparging | Inject air into the aquifer, and the pollutants in the groundwater move into the vadose zone with the air. Combine with the soil vapor extraction method to treat the pollutants in the groundwater | Suitable for soil with good permeability and homogeneous quality |
Electrokinetic remediation | The charged ions of the metal undergo directional migration under the influence of the electric field force, and the pollutants eventually gather together for centralized treatment | Suitable for organic and heavy metal pollution |
Chemical oxidation | Carried out by oxidizing reaction between oxidizing agent and pollutant in groundwater | Easy to affect the geological and ecological environment |
Permeable reactive barrier | A trench is excavated downstream of the hydraulic gradient of the groundwater to form a reaction wall. When the sewage flows through the reaction wall, the pollutants in the groundwater are adsorbed, oxidized, and biodegraded | Low cost and large application scope |