A high-efficiency microbial remediation method for cadmium-contaminated sediments

Abstract

A high-efficiency microbial remediation method for cadmium-contaminated sediments, comprising the following steps: Step 1, taking natural reservoir sediment for SRB enrichment, domestication and expanded culture to obtain purified SRB bacterial liquid; Step 2, the expanded cultured Purified SRB bacteria solution and nano-zero-valent iron jointly repaired Cd-contaminated deposits; step 3, collecting Cd-contaminated deposits repaired by using purified SRB bacteria solution and nano-zero-valent iron at regular intervals; The dominant species of typical SRB at the family level included Desulfolobus, Desulfoenterobacteriaceae, Desulfobacteriaceae, Sulfur-Reducing Bacteriaceae and Desulfovibrioceae. This method is easy to achieve in-situ repair, and has the advantages of simple operation, good repair effect, and environmental friendliness. The immobilization effect of Cd can be enhanced, and the cadmium content in the overlying water can be rapidly reduced, and when there is continuous new cadmium pollution in the overlying water environment of the cadmium-polluted sediment, the method of the invention can realize continuous and efficient restoration.

Description

technical field [0001] The invention relates to the technical field of remediation of heavy metal pollutants, in particular to a method for remediating cadmium-contaminated deposits by combining nanomaterials with microorganisms. Background technique [0002] Due to the characteristics of high toxicity, non-degradability and enrichment along the food chain of heavy metals, heavy metal pollution in water is a serious hazard to the ecological environment and human health. However, heavy metals in the water environment eventually accumulate in sediments under the joint action of adsorption, precipitation, co-precipitation, and biological activities, resulting in more severe heavy metal pollution in sediments. In addition, sediments play a key role in the transportation, morphological transformation and food chain transfer of heavy metals. Once the sediments are disturbed by natural or human activities, the heavy metals accumulated in the sediments will be released into the aqu...

AI Technical Summary

Problems solved by technology

However, there are many difficulties in the practical application of SRB's biological immobilization technology. For example, the invention patent with the publication number CN107138521A and the title of the invention is "a microbial remediation method for cadmium-contaminated sediment", which was added to the sediment system by SRB. After that, it takes up to 166 days to achieve a certain repair effect

This is mainly because some environmental conditions, such as pH, oxidation-reduction potential, electron donor, etc., cannot meet the growth and work of SRB, and it takes a long time for SRB to adapt to the environment of the research system.

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