Biological removal system for secondary pollutants in groundwater remediation

Abstract

The invention provides a biological removal system for secondary pollutants in groundwater remediation. The system comprises an anaerobic reduction system and an aerobic oxidation system which are connected in sequence. The anaerobic reduction system comprises an adjusting tank, an anaerobic reaction tank, a first sedimentation tank and a gas stripping tank, wherein the gas stripping tank is connected with the anaerobic reaction tank through a return pipeline; the aerobic oxidation system comprises an aerobic reaction tank, a second sedimentation tank and a spraying and gas-washing device. A drain pipe of the spraying and gas-washing device is connected with the aerobic reaction tank through a return pipeline; the bottom of the gas stripping tank is connected with a nitrogen pumping device; an exhaust pipe of the gas stripping tank is connected with a gas inlet pipe of the spraying and gas-washing device; and a drain pipe of the first sedimentation tank is connected with a water inletpipe of the aerobic reaction tank through a pipeline. Based on the design of a targeted microbial reaction system, a synergetic and co-promoted biological removal way of two pollutants of SO4<2-> andFe<2+> / Fe<3+> ions introduced by a Fenton reagent is realized, and the whole system is scientific and optimized, efficient and stable, and environment-friendly.

Description

technical field [0001] The invention relates to a biological removal system for secondary pollutants in groundwater restoration, and belongs to the technical field of sewage treatment. Background technique [0002] In-situ chemical oxidation technology is to inject oxidants into the soil or groundwater in the polluted area, and convert the pollutants in the soil layer or aquifer into non-toxic or relatively less toxic substances through oxidation, so as to achieve the purpose of in-situ repair. A cost-effective, widely used in situ restoration technique. [0003] Fenton's reagent is hydrogen peroxide (H 2 o 2 ) and ferrous ion Fe 2+ mixed solution. Because of its strong oxidation ability, wide application range, mild reaction conditions, simple equipment, low energy consumption, and low overall cost, it is the most commonly used oxidizing agent in in-situ chemical oxidation technology. Fe 2+ As a catalyst for the oxidation reaction, ferrous sulfate (FeSO 4 ), introduc...

AI Technical Summary

Problems solved by technology

[0008] Chinese patent CN106984316A provides a method for preparing a high-efficiency heterogeneous Fenton-like catalyst micro-nano dendritic iron-copper alloy, the purpose of which is to solve the problem of secondary pollution caused by the iron sludge produced by the dissolution of Fe ions in the existing Fenton catalyst

However, it is not a Fenton's reagent in the traditional sense, and its application range is narrow, and it also does not solve the problem of introducing a large amount of SO 4 2- The problem

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