Device and method for restoring hexavalent chromium polluted soil in situ

Abstract

The invention provides a device and a method for restoring hexavalent chromium polluted soil in situ. The device comprises a pipe body with one closed end, a carbon brush anode, a carbon cloth cathode, a cation exchange membrane and a load resistor; a plurality of communicating holes are uniformly formed in the side wall of the pipe body, the cation exchange membrane coats the outer side wall of the pipe body, the carbon cloth cathode coats the outer side of the cation exchange membrane, the carbon brush anode is inserted into the pipe body, the interior of the pipe body is also used for containing an anode liquid, one end of the carbon brush anode is connected with the carbon cloth cathode through a titanium wire, and the load resistor is connected with the titanium wire in series. According to the device, the structure is simple, the hexavalent chromium polluted soil can be restored in situ, hexavalent chromium in the soil is reduced into trivalent chromium which is low in toxicity and is not easy to migrate, the restoring process is simple, and the restoring effect is thorough.

Description

technical field [0001] The invention relates to a treatment technology for heavy metal-contaminated soil, in particular to a device and method for in-situ restoration of hexavalent chromium-contaminated soil, which belongs to the technical field of soil treatment. Background technique [0002] Soil is an important material basis for human production and life. Industries such as electroplating, tanning, metallurgy, petrochemicals, and pesticide production can produce a large amount of heavy metals such as copper, chromium, nickel, and lead, which enter the soil through irrigation, precipitation, and atmospheric deposition. Once the soil is polluted, its ecological value, economic value, and social value cannot be brought into play, which not only directly leads to the waste of land resources, but also endangers ecological security and human health. [0003] Among them, chromium and its compounds are widely used as industrial raw materials in various fields. Chromium polluti...

AI Technical Summary

Problems solved by technology

[0006] The Chinese invention patent application document of CN102101123A discloses a method for in-situ remediation of heavy metal-contaminated soil, in which submicron or nanometer iron, fly ash, magnesium-containing preparations and bentonite are mixed according to the ratio of 5~25:40~50:1~10:15~ Mix evenly at a weight ratio of 50 to obtain a heavy metal-contaminated soil remediation agent; after applying a heavy metal-contaminated soil remediation agent with a thickness of 1 to 4 cm on the surface of the heavy metal-contaminated soil, the soil with a thickness of 20 cm on the surface of the contaminated soil and the applied remediation agent are plowed After 3 to 6 months, the heavy metals cadmium, chromium, mercury, lead, arsenic, nickel, zinc, copper, manganese and vanadium in the heavy metal polluted soil are reduced to low-priced immobilized heavy metals and lose their biolo

Images