Method for remediating lead-cadmium combined polluted soil

Abstract

The invention discloses a method for remediating lead-cadmium combined polluted soil. The method is characterized in that sodium chloride is applied to the lead-cadmium polluted soil, and then sedum plumbizincicola is planted to extract cadmium from the soil, so as to achieve the purpose of reducing the content of chloride in the soil; after the sedum plumbizincicola is harvested, water soluble phosphate is applied to the soil, so as to reduce the effectiveness of lead in the soil. The method has the advantages that the remediation is simple and easy to master; the chloride is extracted through plant, and lead is stabilized through phosphate, so that the remediation effect is far more than that of an existing method; chlorine applied to the lead-cadmium combined polluted soil can improve the extraction of the sedum plumbizincicola to cadmium in the soil, and the stability of lead in the soil can be improved through phosphate.

Description

technical field [0001] The invention relates to a contaminated soil remediation technology, in particular to a method for remediating lead and cadmium compound polluted soil by combining water-soluble phosphate, sodium chloride and sedum sedum. Background technique [0002] Lead and cadmium are common polluting heavy metals in soil. The main sources of these polluting heavy metals include mining and smelting of non-ferrous metals and the use of leaded gasoline. In addition, lead and cadmium compound polluted soil is also very common. This kind of polluted soil mainly exists around non-ferrous metal mining or smelting enterprises. For example, the mining and smelting of zinc, copper, lead and other metals can cause soil lead and cadmium pollution. In unpolluted soil, the content of cadmium is generally about 0.1 mg / kg, the content of lead is between 15-35 mg / kg, and the content of lead in the soil near non-ferrous metal smelting enterprises often reaches 100-1000 mg / kg , th...

AI Technical Summary

Problems solved by technology

(2) Affect the types and quantities of soil microorganisms; (3) Soil lead and cadmium enter the human body through the food chain, breathing and other ways, affecting the health of local residents

(4) High content of heavy metals in the soil can enter the water body through surface runoff and other channels, affecting the quality of the water body and the health of aquatic organisms

Although the existing method of phytoremediation can reduce the cadmium content in the soil, the efficiency is low, and the problem of lead pollution in the soil is not considered; and the method of adding stabilizers to the soil in order to stabilize lead and cadmium at the same time is carried out. For remediation, due to the high availability of soil cadmium, the stabilizing effect of the stabilizer on cadmium is poor

[0008] So up to now, the industry has not yet had an effective and finalized remediation method for lead and cadmium compound polluted soil