Method for repairing cadmium and halogenated hydrocarbon contaminated soil

Abstract

The invention provides a method for repairing cadmium and halogenated hydrocarbon contaminated soil. The method for repairing the cadmium and halogenated hydrocarbon contaminated soil comprises the steps of firstly, excavating soil from a cadmium and halogenated hydrocarbon contaminated land parcel; treating the soil into 2-5 mm soil particles by using a crusher; preparing a dilute nitric acid solution; adding the dilute nitric acid solution, which is prepared according to a ratio of 1L / kg, to the soil particles; mixing and stirring an obtained mixture for 30 min; filtering the mixture; addingactivated aluminium oxide to the filtered mixture according to a certain ratio so as to obtain a soil mixture; feeding the soil mixture into a vacuum pyrolysis stirring device; heating the soil mixture to 150-200 degrees centigrade; continuously stirring the soil mixture; preserving the heat of the soil mixture for 30 min; enabling cadmium nitrate and halogenated hydrocarbon in the soil to volatilize so as to separate the cadmium nitrate and the halogenated hydrocarbon from the soil; adding biomass carbon to the soil according to a certain ratio; uniformly mixing the biomass carbon and the soil; and regulating the soil to be alkalescent so as to obtain repaired soil. The method for repairing the cadmium and halogenated hydrocarbon contaminated soil has the advantages that the heat energyconsumption in use is less, the cadmium and the halogenated hydrocarbon in the soil can be effectively separated, the method is simple, the operation is easy, the treatment effect is good, and a purpose of long-acting treatment is achieved.

Description

Technical field: [0001] The invention relates to the technical field of soil pollution remediation, in particular to a method for remediating cadmium and halogenated hydrocarbon contaminated soil. technical background: [0002] There are 1.8 to 2 million cancer cases and 1.4 to 1.5 million deaths in the country every year, which is related to the excessive pollution of agricultural products to a certain extent. Soil heavy metal pollution has gradually become the focus of public attention. [0003] Cadmium (Cd) pollution is the most harmful. Soil cadmium pollution mainly comes from the deposition of cadmium in the atmosphere, the use of pesticides, fertilizers and plastic films, sewage irrigation, sludge fertilization, accumulation of heavy metal-containing waste, and acid wastewater pollution from metal mines. Cd element has been listed by the United Nations Environment Program as the first globally significant hazardous chemical substance. Cd pollution will not only caus...

AI Technical Summary

Problems solved by technology

[0007] For the treatment of cadmium and halogenated hydrocarbon contaminated soil, the existing technology has problems such as low repair efficiency, high treatment cost, and inability to effectively remove soil heavy metal pollution sources, etc.

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