Method and device for restoring polluted soil and treating solid wastes by utilizing electric energy

Abstract

The invention relates to a method and device for restoring polluted soil and treating solid wastes. A cathode reaction tank and an anode reaction tank are respectively arranged at the two ends of soil / solid wastes, a water supply layer is arranged at the bottom of the soil / solid wastes and contains a chemical agent which can improve the solubility of organic pollutants and heavy metals in water, and a replaceable pollutant collecting layer covers the top of the soil / solid wastes which are internally provided with a replaceable artificial focal zone. The temperature value of the soil / solid wastes is increased to dozens of degrees even hundreds of degrees by applying a high voltage and large current; volatile organic pollutants volatile from the soil / solid wastes due to a high temperature, and nonvolatile organic pollutants and the heavy metals rise to the collecting layer along with water and are left in the collecting layer after the water is evaporated; and partial heavy metal ions are transferred to the electrode tank and the artificial focal zone along the electric field direction. Hydrogen and oxygen generated at a cathode and an anode are respectively collected for burning the volatile pollutants in the collecting layer and the focal zone; and the oxygen also can be made into ozone for oxygenizing pollutants in the soil / solid wastes or be cleared out.

Description

technical field [0001] The invention relates to a method and device for repairing polluted soil and treating solid waste, which are invented based on the principle of saline-alkali formation and electrodynamic restoration by using electric energy. Background technique [0002] When wastewater or solid waste generated during industrial production enters the soil, it will cause soil and groundwater pollution. When the site is converted to residential or agricultural land, the soil and groundwater must be restored to eliminate the pollutants. [0003] The main methods of soil and groundwater restoration are: (1) physical restoration: physical separation restoration, solidification / stabilization restoration, steam extraction restoration, electric restoration, etc.; (2) chemical restoration: chemical leaching restoration, solvent extraction restoration, High-temperature incineration restoration, redox restoration, etc.; (3) Bioremediation: prepared bed method, soil composting met...

AI Technical Summary

Problems solved by technology

The disadvantage of electric restoration technology is that if it is used to remove organic pollutants in soil, since organic pollutants are usually not charged, it can only rely on electrodialysis, and the current efficiency of electrodialysis is only a few percent of electromigration, so it is economically feasible. Far inferior to steam extraction and microbial remediation techniques, therefore, not suitable for remediation of organically contaminated soils

In addition, there are two energy waste problems in electric restoration: (1) the heat energy generated in the electric restoration process is slowly released and not used; (2) the oxygen generated by the anode and the hydrogen generated by the cathode are low in production rate, difficult to collect, and are used Emitted to the atmosphere without use

This method cannot be used for heavy metals and low-volatile organic pollutants, and due to the influence of soil permeability, the temperature at the far end of the steam injection well is lower than the temperature around it, resulting in uneven remediation effect

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