Method for restoring soil contaminated by heavy metals

Abstract

A method for repairing the heavy metal polluted soil includes such steps as adding sulfur to the polluted soil, inoculating thio-oxidizing bacteria, and conventionally planting Haichow elsholtzia herbs.

Description

technical field [0001] The invention relates to a repair method for heavy metal polluted soil. Background technique [0002] Since the industrial revolution, environmental problems have become more and more prominent. The pollution of heavy metals and metalloids such as Mn, Pb, Cd, Se, Hg, As, Ni, Zn, Cu, etc. produced by industrial and mining industries has attracted special attention. With the acceleration of urbanization and the rapid development of industry, a large amount of untreated urban waste, mining metallurgy and production of industrial inorganic chemicals, pigments, paints, electroplating, petroleum refining and other factory waste water, as well as atmospheric sediments are continuously discharged into Water and soil; the heavy metal content in the environment has increased sharply, which is no longer suitable for agricultural production and human life. According to statistics, the world's annual average emission of Hg is about 1.15 million tons, Pb is about 5...

AI Technical Summary

Problems solved by technology

[0006] However, at present, the phytoremediation of heavy metal-contaminated soils in my country has not yet entered the stage of engineering practice. The main problem is that the efficiency and rate of phytoremediation are low.

(1) At present, the hyperaccumulator plants with the most promotional value have short plants, low biomass, slow growth and long life cycle, so the repair efficiency is low and it is not easy to mechanize operation

(2), usually a plant only absorbs one or two heavy metals, and has poor tolerance to other metals that coexist in the soil, thus limiting the application of phytoremediation technology in the treatment of compound polluted soil

(3) Limited by the extension depth of the root system, phytoremediation is only suitable for pollution control of surface soil or shallow groundwater

(4) Limited by the bioavailability of pollutants and the transfer efficiency of pollutants to the aboveground, phytoextraction and remediation generally take a long time

The research on the use of sulfur oxidizing bacteria in the field of soil heavy metal bioremediation is still blank

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