An in-situ remediation process of low-concentration organic-contaminated groundwater and its application

Abstract

The invention discloses an in-situ restoration process for low-concentration organic-polluted groundwater, which includes constructing an injection well in the groundwater pollution area, installing a well pipe in the injection well, the bottom of the well pipe is perforated, and communicates with the aquifer, and the perforated The length is greater than the longitudinal extent of the contaminated area; inject oxygen into the aquifer through the injection well, and perform aerobic control on the aquifer; after performing anaerobic control on the aquifer for 5 days or more, cycle aerobic control and anaerobic control to groundwater The degradation of organic pollutants reached the standard. The present invention artificially adjusts the dissolved oxygen content of groundwater, controls the orderly alternation of aerobic and anaerobic conditions, utilizes the inherent components such as iron minerals, organic matter and microorganisms in the aquifer, and realizes the activation of divalent iron minerals under aerobic conditions Oxygen produces hydroxyl radicals for the oxidative degradation of low-concentration organic pollutants, and microorganisms use organic carbon to regenerate ferrous minerals under anaerobic conditions.

Description

Technical field[0001]The invention relates to the field of groundwater treatment, in particular to an in-situ repair process for low-concentration organic polluted groundwater and its application.Background technique[0002]Groundwater is an important source of water supply, and most of the world's drinking water and agricultural irrigation water come from groundwater. There are different degrees of hydraulic connection between groundwater and surface water bodies such as rivers and lakes, and the quality of groundwater directly affects the environmental quality of surface water. At the same time, groundwater is also the main source of water conserving the ecological environment such as wetlands and vegetation, and has a very important impact on the quality of the ecological environment. However, groundwater pollution is very serious. In groundwater pollution, the pollution of groundwater in a small area characterized by source pollution has attracted great attention due to the high d...

AI Technical Summary

Problems solved by technology

[0004] However, the above in-situ remediation technologies for groundwater have the following problems when dealing with low-concentration organic pollutants: (1) It is impossible to efficiently and economically treat low-concentration organic pollutants up to the standard

The above technologies can usually efficiently and economically reduce medium and high concentrations of organic pollutants to a very low level, but it will be very difficult and costly to further reduce them below the standard value

(2) The processing principle is relatively simple

The principle of existing remediation technology to remove pollutants is either oxidation or reduction, which is more effective for pollutants that can be oxidized or reduced, but not for many organic pollutants that cannot be completely degraded and detoxified by oxidation or reduction. Does not work, such as nitro compounds, etc.

(3) Insufficient utilization of the inherent components of the aquifer

Ferrous iron minerals in the aquifer have the function of activating oxygen to generate hydroxyl radicals to degrade organic pollutants, and microorganisms can use organic matter to reduce ferric iron to regenerate ferrous iron after oxygen is exhausted, but such a natural process has not been used effectively

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