Application of microbial preparation for efficiently converting heavy metal cadmium in polluted soil

Abstract

The invention discloses an application of a microbial preparation for efficiently converting heavy metal cadmium in polluted soil. The microbial preparation is prepared by performing enriched cultivation on the following two mixed floras: (1) candida mycoderma bacteria, aspergillus monicus, rhodosporidium toruloides and cryptococcus which form a flora 1; and (2) acidithiobacillus thiooxidans, leptospirillum ferrooxidans, acidithiobacillus caldus, sulfobacillus thermosulfidooxidans, acidithiobacillus ferrooxidans and thermos ferric bacteria which form a flora 2. By using the microbial preparation to treat the cadmium polluted soil, the metal cadmium is converted from being indissolvable into being soluble and the removal rate is 70-82%. The microbial preparation disclosed by the invention has the advantages of being high in conversion efficiency, short in period, low in cost, free of secondary pollution, easy to popularize and the like.

Description

technical field [0001] The invention belongs to the technical field of microbial treatment of heavy metal pollution, and in particular relates to the application of a microbial bacterial agent capable of efficiently biologically transforming the form of cadmium in polluted soil. Background technique [0002] In recent years, my country has achieved world-renowned achievements in economic development. However, excessive industrial activities have brought serious environmental pollution, posed a serious threat to the health of residents, and brought huge hidden dangers to the sustainable development of society, economy and environment. . my country's rural environment is facing a variety of environmental problems, mainly including soil heavy metal pollution, soil fertility decline, cultivated land salinization, river water eutrophication, and environmental pollution caused by the abuse of pesticides, fertilizers, and insecticides. [0003] According to relevant national data, ...

AI Technical Summary

Problems solved by technology

[0005] Among the relevant patents that have been applied for in China, the patent "A Method for Microbial Remediation of Heavy Metal Contaminated Soil" (application number: 201110122739.6, publication date: 2011‐11‐16) discloses a method of treating soil with Rhodobacter sphaeroides preparations combined with flooding The method, whose working principle is mainly to use Rhodobacter sphaericus to absorb heavy metals after multiplying in a large amount in a water-rich anaerobic environment, and then infiltrate into the ground through water to reduce the concentration of heavy metals in the soil, but the soil cannot be used for planting operations during the treatment process. The economic cost is high. On the other hand, the strains are too single, the universality is poor, the scope of application is small, and the types and degrees of heavy metals that can be treated are relatively low.

The patent "Heavy Metal Contaminated Soil Microbial Restoration Agent and Its Application" (application number 201410682558.2, publication date: 2015‐04‐22) discloses a heavy metal contaminated soil treatment agent using Bacillus subtilis and Candida tropicalis as active ingredients, The bioremediation agent of this invention can adsorb a certain proportion of heavy metals and can remain in the soil for a period of time, but Candida tropicalis is anaerobic and cannot survive for a long time in dry and ventilated soil. Aerobic bacteria cannot survive for a long time in wet soil, and the living environment of the two effective strains conflicts. On the other hand, there are too few effective strains. Since each microorganism has its own limitations, its effect on soil treatment is neither long-lasting nor long-lasting. , not comprehensive