CN-121974442-A - Hexavalent chromium-polluted groundwater environment-friendly restoration system and application

Abstract

The application discloses a hexavalent chromium pollution underground water green restoration system and application thereof, comprising a restoration well main body and a non-contact sustainable electron injection system arranged in the restoration well main body, wherein the restoration well main body comprises a shaft and a through hole arranged on the wall of the shaft, the non-contact sustainable electron injection system comprises a medicament chamber and a graphite cathode plate, the medicament chamber is a sealed space formed by enclosing a proton exchange membrane and a sealing plug, a graphite anode plate and a sodium dithionite solution are arranged in the medicament chamber, the graphite cathode plate is electrically connected with the graphite anode plate, and the non-contact sustainable electron injection hexavalent chromium pollution underground water green restoration method does not need to add a reducing agent to an aquifer, avoids secondary pollution risks caused by the reducing agent and products thereof, and realizes green and efficient hexavalent chromium underground water restoration.

Inventors

• LI JUN
• CHENG XIANFENG
• WU MENGTING
• WU JI
• ZHU JIE
• YUAN SONGHU
• LI XINYI
• YU ZIWEI
• LI HANG
• LIU HUARUI
• LIU RONG
• Xiong Yiding
• LIU JIE

Assignees

• 武汉基建环保工程有限公司

Dates

Publication Date

20260505

Application Date

20260403

Claims (10)

1. 1. The hexavalent chromium pollution underground water green restoration system is characterized by comprising a restoration well main body (1) and a non-contact sustainable electron injection system (2) arranged in the restoration well main body (1); the repair well main body (1) comprises a well bore (3) and a through hole (4) arranged on the wall of the well bore (3); The non-contact sustainable electron injection system (2) comprises a medicament chamber (5) and a graphite cathode plate (9), wherein the medicament chamber (5) is a closed space formed by enclosing a proton exchange membrane (7) and a sealing plug (6), a graphite anode plate (10) and sodium dithionite solution are contained in the medicament chamber (5), and the graphite cathode plate (9) is electrically connected with the graphite anode plate (10).
2. 2. The hexavalent chromium-polluted underground water green repair system according to claim 1, wherein gauze is sleeved outside the shaft (3), and the pore size of the gauze is 40-250 meshes.
3. 3. The hexavalent chromium-polluted underground water green repair system according to claim 1, wherein the concentration of the sodium dithionite solution is 1-1400 mmol/L, and the pH value is more than or equal to 10.
4. 4. The hexavalent chromium-polluted groundwater green restoration system according to claim 1, wherein the tolerance pH value of the proton exchange membrane (7) is 0-12, and the proton exchange capacity is more than or equal to 0.9 meq/g.
5. 5. The hexavalent chromium-polluted groundwater environment-friendly restoration system according to claim 1, wherein the part of the chemical chamber (5) immersed below the water level of the shaft (3) is sealed by a proton exchange membrane (7), the top end of the chemical chamber is sealed by a sealing plug (6), and the sealing plug (6) is provided with a wire through hole.
6. 6. The green repair system for hexavalent chromium-polluted groundwater according to claim 1, wherein the repair well main body (1) contains hexavalent chromium-polluted groundwater, and the non-contact sustainable electron injection system (2) is immersed in the hexavalent chromium-polluted groundwater.
7. 7. The hexavalent chromium-contaminated groundwater green repair system according to claim 4, wherein the proton exchange membrane (7) is a Nafion-N117 proton exchange membrane.
8. 8. The hexavalent chromium-polluted underground water green restoration system according to claim 1, wherein the restoration well main body (1) is of a hollow cylindrical structure, the inner diameter of the hollow cylindrical structure is 10-50cm, and the restoration well main body (1) extends to 0.5-2 m below the bottom of a polluted aquifer.
9. 9. Hexavalent chromium-contaminated groundwater green remediation system according to claim 1, characterized in that the agent chamber (5) is suspended inside the remediation well body (1), at least 50% of the total height of the agent chamber (5) being immersed below the water line of the remediation well body (1).
10. 10. Use of the hexavalent chromium-contaminated groundwater environment-friendly remediation system of any one of claims 1-9 in the field of groundwater remediation.

Description

Hexavalent chromium-polluted groundwater environment-friendly restoration system and application Technical Field The invention relates to the technical field of groundwater remediation, in particular to a hexavalent chromium-polluted groundwater green remediation system and application. Background Inorganic heavy metals and nondegradable organic pollutants in groundwater pollution widely exist, and form a continuous threat to ecological environment and public health. The hexavalent chromium with high toxicity is used as an important chemical substance in electroplating, tanning and metal passivation processes, and enters the underground environment in a large amount through industrial wastewater, slag infiltration, dust sedimentation and other ways. Under the acidic condition, hexavalent chromium usually exists in an anion form, so that the migration capability is obviously enhanced, and the repair and treatment difficulty is extremely high. Currently, in-situ chemical reduction remediation technology is a common means of treating hexavalent chromium-contaminated groundwater by adding a reducing agent (e.g., alkaline sodium dithionate) to the contaminated area, reducing it to a low-toxicity form, and reducing Cr (VI) to Cr (III). However, the conventional injection type in-situ remediation technology has inherent limitations that the addition of the alkaline reducing agent changes inherent pH, conductivity and the like of the underground water, so that the in-situ microbial community structure and function are affected, and the residual chemical reducing agent can also cause secondary pollution and further influence the ecological environment. Therefore, there is a need to provide a solution to green and efficiently perform hexavalent chromium groundwater remediation. Disclosure of Invention In view of the above, the application provides a hexavalent chromium pollution groundwater environment-friendly restoration system and application thereof, which are used for solving the problem of how to realize environment-friendly and efficient restoration of hexavalent chromium groundwater. In order to achieve the technical purpose, the application adopts the following technical scheme: the application provides a hexavalent chromium pollution underground water green repair system, which comprises a repair well main body and a non-contact sustainable electron injection system arranged in the repair well main body, wherein the repair well main body comprises a shaft and a through hole arranged on the wall of the shaft, the non-contact sustainable electron injection system comprises a medicament chamber and a graphite cathode plate, the medicament chamber is a closed space formed by enclosing a proton exchange membrane and a sealing plug, a graphite anode plate and a sodium dithionite solution are arranged in the medicament chamber, and the graphite cathode plate is electrically connected with the graphite anode plate. Preferably, gauze is sleeved outside the shaft, and the pore diameter of the gauze is 40-250 meshes. Preferably, the concentration of the sodium dithionite solution is 1-1400 mmol/L, and the pH value is more than or equal to 10. Preferably, the tolerance pH value of the proton exchange membrane is 0-12, and the proton exchange capacity is more than or equal to 0.9 meq/g. Preferably, the part of the medicament chamber immersed below the water level of the shaft is sealed by a proton exchange membrane, the top end of the medicament chamber is sealed by a sealing plug, and the sealing plug is provided with a wire through hole. Preferably, the repair well main body contains hexavalent chromium-polluted underground water, and the non-contact sustainable electron injection system is soaked in the hexavalent chromium-polluted underground water. Preferably, the proton exchange membrane is a Nafion-N117 proton exchange membrane. Preferably, the repair well body is of a hollow cylindrical structure, the inner diameter of the hollow cylindrical structure is 10-50cm, and the repair well body extends to 0.5-2 m below the bottom of the polluted aquifer. Preferably, the medicament chamber is suspended within the repair well body, and at least 50% of the total height of the medicament chamber is immersed below the repair well body water line. In a second aspect, the application provides an application of a hexavalent chromium-polluted groundwater environment-friendly restoration system in the field of groundwater restoration. The beneficial effects of the application are as follows: The method can be used for reducing the concentration of hexavalent chromium-containing pollution plumes and preventing further diffusion of the pollution plumes, the hexavalent chromium in the groundwater is migrated and diffused into a repair well and reduced by an electron injection system in a non-contact mode, the electron injection system can be taken out after sodium dithionite is consumed, and the electron injection system is replace