Boiling type micro-foam soil pollution desorption device and method suitable for coking field

Abstract

The invention discloses a boiling type micro-foam soil pollution desorption device and method suitable for a coking field, the device comprises a pollutant desorption device, an ozone conveying pipeline, an airflow conveying pipeline, a micro-foam generation device and a waste gas and waste liquid collection device, and the ozone conveying pipeline is connected with an ozone inlet of the pollutantdesorption device to provide ozone to the pollutant desorption device to oxidize organic pollutants in coking soil; the airflow conveying pipeline is connected with an airflow inlet of the pollutantdesorption device and provides airflow for the pollutant desorption device so as to realize soil fluidization and boiling; the micro-foam generating device is connected with a foam inlet; the waste gas and waste liquid collecting device is connected with a waste liquid outlet and a waste gas outlet; the desorption method is divided into three stages: (1) performing ozone oxidation and soil boiling, and starting an ozone conveying pipeline and an airflow conveying pipeline; (2) eluting surfactant micro-foam, closing the ozone conveying pipeline and the airflow conveying pipeline, and starting the micro-foam generating device; and (3) collecting waste gas and waste liquid.

Description

technical field [0001] The invention relates to soil remediation technology for polluted sites, in particular to a boiling microfoam soil pollution desorption device and method suitable for coking sites. Background technique [0002] In the remediation process of contaminated soil, due to the strong lipophilicity of polycyclic aromatic hydrocarbons, once pollution occurs, it will be difficult to remediate the contaminated medium, and the water solubility is low, and the n-octanol water partition coefficient is large, so it is easy to be absorbed in the organism. and enriched in lipids. At present, the research on the remediation technology of soil polycyclic aromatic hydrocarbon pollution is relatively extensive at home and abroad. Among the existing soil remediation technologies, the chemical leaching method is widely used in the remediation of organic contaminated soil due to its simple operation, low cost and good remediation effect. However, the pore effect is prone to ...

AI Technical Summary

Problems solved by technology

This system is suitable for in-situ remediation of soil, but it is difficult to remove the surfactant adsorbed on the soil, and it is impossible to determine whether there is foam residue in the soil

In the process of in-situ injection, because the foam is squeezed by the soil during injection, it is easy to break and return to a liquid state, and many problems in the chemical leaching method are still unavoidable.

[0005] Most of the existing inventions are aimed at improving the micro-foam generating device. The micro-foam desorption device is less and immature, and the foam injection is uneven. Surfactant foam flushing technology for contaminated soil remediation. This invention uses surfactants and nitrogen to produce heterotopic foam. The foam properties are controlled by controlling the foam gas-liquid ratio and particle size, and foam flushing is performed by pressurized injection.

In this invention, the foam is less stable in the soil column, and only exists in the form of foam within a certain distance from the top of the column. It is almost equivalent to the effect of chemical leaching at the bottom of the column, and is still affected by the channel effect. Moreover, this technology requires high foam stability, and the operation process is cumbersome and time-consuming.

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