Synergistic leaching solution of polycyclic aromatic hydrocarbons and chromium composite polluted soil in electroplating industry and its application

Abstract

The invention discloses polycyclic aromatic hydrocarbon and chromium combined polluted soil synergistic leacheate in the electroplating industry and application thereof. Polluted soil particles are crushed and screened and then the soil particles are put into soil multi-element ex-situ leaching remediation equipment, vegetable oil and sophorolipid compound mixed leacheate are added, meanwhile, thecontinuous ex-situ synergistic leaching is carried out by adopting an ultrasonic strengthening and heating treatment mode. Then humulus japonicus is inoculated into the leached soil, and a nutrient source buffer solution which is equal to 1-2.5% of the mass of the soil is applied. The repair is completed through artificial culture growth. By means of the method, organic-inorganic composite pollutants such as polycyclic aromatic hydrocarbon and chromium in the soil can be efficiently leached and removed at the same time, the humulus japonicus is inoculated and exogenous nutrient substances areadded, the deep degradation of residual polycyclic aromatic hydrocarbon in the soil after leaching is facilitated, and the rapid recovery of microbial ecological functional diversity of the soil environment after leaching is also facilitated.

Description

technical field [0001] The invention belongs to the technical field of remediation of polycyclic aromatic hydrocarbons and chromium composite polluted soil in electroplating industry polluted sites, and in particular relates to a synergistic eluent for polycyclic aromatic hydrocarbons and chromium composite polluted soil in the electroplating industry and its application. Background technique [0002] In recent years, with the in-depth implementation of policies such as "retreating from two to three" and "retreating from cities and entering parks" in China, a large number of small and medium-sized electroplating enterprises in coastal areas along the river have been gradually closed down and relocated, resulting in a large number of organic- The site of inorganic compound pollution appears. Due to the backwardness of the historical production process, there will be a lot of waste water, waste gas, solid waste leakage and disorderly discharge in the production process of the ...

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Problems solved by technology

[0005] For the soil where organic pollutants and chromium co-exist, the publication numbers: CN107824608A, CN106903154A and CN107671118A respectively provide a method and device for the remediation of volatile halogenated hydrocarbons and chromium composite polluted soil, a thermal remediation method for organic polluted soil and Simultaneously restore the method of DDT and heavy metal chromium compound polluted soil, the above method, from the angle of thermal repair and the angle of adding reducing agents, removes the organic-inorganic heavy metal chromium compound pollutants in the soil, but the thermal repair technology often requires repair The equipment process is complicated and the repair cost is expensive, and the addition of chemical reducing agents will have a significant negative impact on the ecological function diversity of the soil indigenous flora. The above-mentioned patent does not refer to the better improvement and restoration of soil ecology after restoration

[0006] Through relevant literature review and patent search, no public publication and acceptance of the synergistic leaching-plant joint repair method for polycyclic aromatic hydrocarbons and chromium compound polluted soil in the electroplating industry has been found. The prior art closest to the present invention is the leaching agent Restoration technology, publication number: CN105598148A, provides a method for remediation of volatile organic compounds and heavy metal chromium composite polluted soil, but the present invention uses a chemical eluent compounded with polyacrylamide and dilute acetic acid solution to remove Volatile halogenated hydrocarbons and heavy metal chromium, but the disturbance and damage of chemical leaching agents to the ecological functions of soil indigenous microorganisms will be very significant. At the same time, the organic pollutants targeted by this method are mainly volatile halogenated hydrocarbons, and polycyclic aromatic hydrocarbons are not considered and other substances, and the original concentration of chromium in the polluted soil is lower than 1000 mg / kg, and the situation of the ultra-high concentration of chromium remaining in the soil of the electroplating industry polluted site has not been explained; the publication number: CN106694535A, provides a heavy metal and organic compound pollution Soil remediation technology and process. Although this method involves leaching and combined plant remediation, the method is to repair by building a leaching slope and treating the leachate. The remediation process is complicated, and the contact reaction between contaminated soil particles and leaching agents is difficult to fully , the required cycle is long and takes two years, it is difficult to quickly remove organic-inorganic pollutants from the soil in a short period of time, and the heavy metal pollutants mentioned in this method do not involve chromium

[0007] The main defects in the existing technology are: lack of synergistic leaching technology for synchronous removal of polycyclic aromatic hydrocarbons and heavy metal chromium complex pollutants in soil, the selected chemical leaching agent is not environmentally friendly, and it is difficult to achieve simultaneous removal of organic-inorganic pollutants. Simultaneous high-efficiency elution and removal, incomplete removal of pollutants, unsatisfactory restoration of soil environmental ecological functions after leaching, and obvious lack of follow-up in the research and development of related collaborative supporting restoration technologies, etc., so the market application prospects of existing technologies are not clear

[0008] The main reasons for the defects are: In recent years, there have been a large number of polycyclic aromatic hydrocarbons and heavy metal chromium compound pollution sites caused by the relocation and closure of electroplating enterprises, and the early scientific and technological personnel paid relatively little attention and research and development to this kind of contaminated soil remediation technology , or only pay attention to the remediation technology of single PAH and single chromium contaminated soil, but relatively little attention has been paid to the simultaneous removal of PAH and chromium-contaminated soil and the development of corresponding remediation technology; the existing remediation technology is mainly for the original Relatively low concentrations of chromium or polycyclic aromatic hydrocarbons pollute farmland soil, while for high concentrations of organic-inorganic compound polluted soil, the remediation effect cannot meet the remediation needs; the existing remediation technology can improve the diversity of microbial ecological functions in the remediation soil environment. Fast recovery and remodeling are less considered

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