Combined chemical elution-phytoremediation method of polybrominated diphenyl ethers and heavy metals in composite contaminated soil

Abstract

The chemical elution-plant joint remediation method of PBDE and heavy metal compound polluted soil, firstly crush and screen the polluted soil particles; then put the soil particles in the multi-component heterotopic soil remediation equipment, add mixed eluent, and use ultrasonic Continuous ectopic synergistic elution is carried out in the way of strengthening and heating treatment; then the eluted soil is inoculated with Shuitongcao, and a nutrient source buffer solution equivalent to 15%-30% of the soil quality is applied; artificial culture growth completes the restoration. It can efficiently elute and remove PBDEs and various heavy metals in the soil at the same time; inoculation of water grass and addition of exogenous nutrients are conducive to the deep degradation of residual PBDEs after soil elution, and also contribute to the diverse ecological functions of microorganisms in polluted soil environments Restoration of sex and stability.

Description

technical field [0001] The invention belongs to the technical field of remediation of organic-inorganic composite polluted soil, and in particular relates to a rapid chemical elution-plant combined restoration method of polybrominated diphenyl ether and multiple heavy metal composite polluted soil. Background technique [0002] In recent years, with the rapid development of my country's economy and the continuous improvement of people's living standards, a large number of new electronic products (such as: computers, mobile phones, printers, scanners, navigators and satellite TVs, etc.) have gradually been widely used by people. The replacement and upgrading cycle of electronic science and technology has become shorter, and a large number of waste electronic waste products have been quickly eliminated and discarded, resulting in the emergence of a large number of polluted areas around cities and towns in my country where electronic waste accumulates. In such polluted areas, du...

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Problems solved by technology

Among them, the application numbers: CN201110278862 and CN201410071012 respectively provide a method for highly efficient PBDE-degrading bacteria and its application and a method for repairing PBDE-contaminated soil granules and its application, but these two methods are mainly aimed at single PBDE The degradation of ether organic pollutants does not take into account the situation of compound polluted soil with polybrominated diphenyl ethers and heavy metals. At the same time, the bacterial strain provided in CN201110278862 is mainly aimed at degrading low-concentration polybrominated diphenyl ethers in soil, and the white-rot fungus hyphae fermentation provided in CN201410071012 The solution is mainly aimed at degrading low-concentration polybrominated diphenyl ethers in the soil, but the effect is not good for the remediation of high-concentration polluted soils; application number: CN201310545065 provides a method for electrically remediating polybrominated diphenyl ether-contaminated soils, but this method requires Only when the soil pH value is adjusted to 3-4 can the efficient degradation of polybrominated diphenyl ethers be achieved, so the disturbance and damage to the ecological function of the restored soil are relatively large, and the restoration of the environmental ecological function of the restored soil is not taken into account; application number: CN201010220381 Provides a microbial fuel cell and its application method in the degradation of polybrominated diphenyl ethers, but this method is mainly aimed at the degradation of polybrominated diphenyl ethers in the water environment, and it is difficult to carry out remediation engineering operations on large-scale polybrominated diphenyl ether-contaminated soil areas; application No.: CN201310077333 and CN200510086490 respectively provide a method for in-situ remediation of PBDE-contaminated soil using nano-Ni / Fe bimetallic particle composite materials and a method for rapidly degrading PBDEs with nano-iron powder. Although these two methods can effectively degrade The parent compound of polybrominated diphenyl ether is removed, but the degradation products of polybrominated diphenyl ether still remain in the soil, and the physiological toxicity and environmental risk of its degradation secondary products or nano-remediation materials in the soil environment are not considered; application number: CN201310636248, provided A new type of soil purifying agent and its application method for the remediation of polybrominated diphenyl ether-contaminated soil is proposed. This method uses anionic surfactants and iron compounds to form metal complexes and add them to the soil to improve the bioavailability of polybrominated diphenyl ethers. Through the elimination of soil filtrate, the removal of polybrominated diphenyl ethers is realized, but this method is only aimed at the removal of a single low-concentration polybrominated diphenyl ether, and has not considered the situation of heavy metal complex pollution at the same time; application number: CN200810239353, provides a surfactant to increase A method for degrading polybrominated diphenyl ethers combined with UV technology, but this method is mainly aimed at the solubilization and photodegradation of polybrominated diphenyl ethers in water, and the chemical surfactants used have certain environmental toxicity risks. Take into account less

[0004] Through relevant literature review and patent search, no publication and acceptance of chemical elution and remediation technology related to polybrominated diphenyl ether and heavy metal compound polluted soil has been found. The prior art closest to the present invention is surfactant elution technology, application number: CN201010558286.7 provides a method for rinsing and repairing organic-inorganic composite polluted soil. The method mainly uses sodium lauryl sulfate and diethylamine disuccinic acid to leaching the polluted soil, but the organic pollutants targeted by the method are mainly It is chlorobenzene and trichlorethylene organic pollutants, and the heavy metals targeted are mainly copper and chromium polluted soil; application numbers: CN200810123622 and CN201210486441.8 respectively provide a method for leaching and repairing heavy metal-organic compound polluted soil and a A chemical-microbial joint remediation method for compound contaminated soil of polycyclic aromatic hydrocarbons and heavy metals. utility verification

[0005] The main defects in the existing technology are: lack of synergistic elution technology for high-concentration polybrominated diphenyl ethers and heavy metal compound-contaminated soil at the same time, less types of organic-inorganic pollutants, and difficulty in achieving simultaneous synchronization of organic-inorganic pollutants Efficient elution and removal, poor environmental friendliness of the selected chemical eluent, incomplete removal of pollutants, unsatisfactory restoration of soil environmental ecological functions after elution, and obvious lack of follow-up in the research and development of related collaborative supporting restoration technologies, etc. The market application prospect of existing technology is not clear

[0006] The main reasons for the defects are: In recent years, there have been a large number of PBDE and heavy metal compound pollution sites caused by the irregular recycling operations of electronic waste treatment plants, and the early scientific and technological personnel have paid relatively little attention to and developed such contaminated soil remediation technologies. The existing remediation technology is mainly aimed at the farmland soil with relatively low pollution concentration, but the remediation effect is not good for the site soil with high pollution concentration; The recovery balance consideration is less

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