CN-119870130-B - Groundwater remediation system and remediation method

CN119870130BCN 119870130 BCN119870130 BCN 119870130BCN-119870130-B

Abstract

The invention belongs to the technical field of groundwater pollution remediation, and particularly discloses a groundwater remediation system and a groundwater remediation method. The repairing system comprises a pumping well, a circulating well and a water injection well, wherein the pumping well is connected with the circulating well through a first water pipe, and the circulating well is connected with the water injection well through a second water pipe. The circulating well and the water injection well comprise an inner well pipe, an outer well pipe, an intermediate packing layer positioned between the inner well pipe and the outer well pipe, and an outer packing layer surrounding the outer side wall of the outer well pipe. A first-stage single-well internal and external double-circulation system is formed in the circulation well and the water injection well, a second-stage underground water circulation system is formed between the pumping well and the circulation well and between the circulation well and the water injection well, and a third stage groundwater circulation system forming a groundwater pollution area between the pumping well and the water injection well along the groundwater flow direction. The invention has the remarkable advantages of high efficiency, high quality, low cost, flexibility, applicability, small engineering quantity, environmental protection, safety and the like.

Inventors

YAO MENG
XIE YAN
ZHANG SHUCAI

Assignees

中国石油化工股份有限公司
中石化安全工程研究院有限公司

Dates

Publication Date: 20260508
Application Date: 20231025

Claims (3)

1. The underground water remediation system is characterized by comprising at least one pumping well, at least one circulating well positioned at the upstream of the pumping well and at least one water injection well positioned at the upstream of the circulating well, wherein the pumping well and the circulating well are connected through a first water pipe, and the circulating well and the water injection well are connected through a second water pipe; The circulating well and the water injection well comprise an inner well pipe, an outer well pipe, an intermediate packing layer positioned between the inner well pipe and the outer well pipe and an outer packing layer surrounding the outer side wall of the outer well pipe; Forming a first-stage single-well internal and external double-circulation system in the circulation well and the water injection well, forming a second-stage underground water circulation system between the pumping well and the circulation well and between the circulation well and the water injection well, and forming a third-stage underground water circulation system of an underground water pollution area between the pumping well and the water injection well along the underground water flow direction; the wall of the pumping well is divided into a watertight pumping well wall positioned at the middle upper part and a watertight pumping well wall positioned at the lower part, and a plurality of watertight micropores are formed in the watertight pumping well wall; The well wall of the circulating well is divided into an upper circulating well wall, a middle impermeable circulating well wall and a lower permeable circulating well wall, wherein the circulating well wall is divided into a first upper impermeable well wall and a first lower permeable well wall, and a plurality of permeable micropores are formed in the first lower permeable well wall and the permeable circulating well wall; the top end of the inner well pipe of the circulating well is leveled with the bottom end of the first lower permeable well wall, and the bottom end of the inner well pipe of the circulating well is leveled with the top end of the permeable circulating well wall; the well wall of the water injection well is divided into an upper water injection well wall, a middle water injection well wall and a lower water injection well wall, the water injection well wall is divided into a second upper water injection well wall and a second lower water injection well wall, and a plurality of water injection micropores are formed in the second lower water injection well wall and the water injection well wall; the top end of the inner well pipe of the water injection well is leveled with the bottom end of the second lower permeable well wall, and the bottom end of the inner well pipe of the water injection well is leveled with the top end of the permeable water injection well wall; the top end of the external packing layer of the circulating well is leveled with the top end of the first lower permeable well wall, and the bottom end of the external packing layer of the circulating well is leveled with the bottom end of the permeable circulating well wall; The top end of the external packing layer of the water injection well is leveled with the top end of the second lower permeable well wall, and the bottom end of the external packing layer of the water injection well is leveled with the bottom end of the permeable water injection well wall; One end of the first water pipe extends downwards into the pumping well, the other end of the first water pipe extends downwards into the middle packing layer of the circulating well and upwards turns over into an inner well pipe of the circulating well after penetrating through the bottom end of the middle packing layer of the circulating well, and a first filter, a first water pump, a first water storage tank and a first dissolved air pump are sequentially connected in series in reverse groundwater flow direction on the first water pipe positioned on the uphole part; the other end of the second water pipe extends downwards into the middle packing layer of the water injection well and upwards turns over into the inner well pipe of the water injection well after passing through the bottom end of the middle packing layer of the water injection well, and a second filter, a second water suction pump, a second water storage tank and a second dissolved air pump are sequentially connected in series in reverse groundwater flow direction on the second water pipe positioned on the uphole part; The well heads of the pumping well, the circulating well and the water injection well are all provided with sealing well covers, and the sealing well covers are provided with gas collecting pipelines; One end of a gas collecting pipeline on the sealing well cover of the circulating well and one end of a gas collecting pipeline on the sealing well cover of the water injection well extend downwards into the pumping well, and the gas collecting pipeline on the sealing well cover of the pumping well is connected with the tail gas treatment device.
2. A groundwater remediation method, characterized by being applied to the groundwater remediation system of claim 1, comprising the steps of: S1, forming a circulation loop between a pumping well and a circulation well and forming an inner and outer double circulation loop of the circulation well; Pumping water from a pumping well through a first water pipe by using a first water pump, enabling the water to enter a first water storage tank after passing through a first filter, enabling water discharged from the first water storage tank to be compressed and dissolved in water through a first dissolved air pump, and then enabling the water to be sent into an inner well pipe of a circulating well through the first water pipe, wherein water flow is sprayed out from the top of the inner well pipe of the circulating well, a part of water flows downwards along an intermediate packing layer of the circulating well, another part of water flows to an external packing layer of the circulating well through a first lower permeable well wall, and then water flows from top to bottom and is sucked into the circulating well under the negative pressure in the circulating well through the permeable circulating well wall; S2, forming a circulation loop between the water injection well and the circulation well and forming an inner circulation loop and an outer circulation loop of the water injection well; pumping water from the circulating well through a second water pipe by using a second water suction pump, enabling water from the second water storage tank to enter a second water storage tank after passing through a second filter, enabling water discharged from the second water storage tank to be compressed and dissolved in water through a second dissolved air pump, and then sending the water into an inner well pipe of the water injection well through a second water pipe, wherein water flow is sprayed out from the top of the inner well pipe of the water injection well, a part of water flows downwards along an intermediate packing layer of the water injection well, another part of water flows to an external packing layer of the water injection well through a second lower permeable well wall, and then flows from top to bottom to enter the water injection well again under the negative pressure suction effect in the water injection well through the permeable water injection well wall; S3, along the flow direction of the underground water, forming a circulation loop between the pumping well and the water injection well.
3. The groundwater remediation method according to claim 2, wherein the tail gas of the water injection well and the circulation well is introduced into groundwater in the pumping well, and the tail gas of the pumping well is delivered to the tail gas treatment device for treatment and then discharged.

Description

Groundwater remediation system and remediation method Technical Field The invention belongs to the technical field of groundwater pollution remediation, and particularly relates to a groundwater remediation system and a groundwater remediation method. Background With the continuous development of human economic activities, the problem of groundwater pollution is becoming more interesting. Groundwater pollution has become one of the major environmental problems in urban and industrialized areas in many countries and regions around the world. Due to the factors of harmful substance emission, garbage stacking, oil stain leakage and the like caused by human activities such as industry, agriculture and the like, the underground water account is seriously polluted, and the water source which should be clean and available originally is threatened. Groundwater remediation techniques include ectopic remediation techniques and in situ remediation techniques. The ex-situ remediation technology is also called a remote replenishment method (P & T), and is a technology for pumping out polluted underground water, treating the polluted underground water and then conveying the polluted underground water to a remote site for treatment. Specific operational steps typically include extracting contaminated groundwater, treating at a treatment facility, injecting purified water into a clean groundwater area after treatment, and the like. The ex-situ remediation technology can efficiently remove pollutants in groundwater, and is suitable for part of pollution sites where effective treatment is difficult to achieve, such as large-scale, especially deep or uncontrollable pollution sources. In recent years, the application of electro-oxidation technology and photocatalysis technology in particular further improves the efficiency and the treatment effect of the ex-situ repair technology. In the process, the groundwater is required to be subjected to multiple steps of extraction, transportation, treatment, reinjection and the like, so that a certain safety risk and secondary pollution are possible. The in-situ treatment technology of groundwater is also called an in-situ repair method (IST), which is a technology for carrying out treatment on the site of a pollution source, and the treatment process is directly carried out in the groundwater range, so that the method has the advantages of no damage to the soil layer structure, high treatment efficiency, low cost and the like. It requires less upstream and downstream control than the ex-situ repair technique, and is more commonly used in practice. The main modes of in-situ repair technology include biological repair, chemical repair, physical repair and the like. Bioremediation is to weaken or remove groundwater pollutants by utilizing the interaction of microorganisms and the environment, and has wide application range and low cost. Chemical remediation is one of the important ways to repair a groundwater environment by injecting redox agents and other anti-pollution materials to alter the groundwater environment so that the pollutants are transferred or converted. The physical repair technology is a groundwater repair technology for repairing pollution based on a physical mechanism, and aims to realize the control of the migration and transfer process of the pollutants of the groundwater body by changing environmental parameters such as permeability coefficient, porosity, medium property and the like, so that the polluted groundwater body is purified. Common in-situ physical repair techniques include activated carbon adsorption, groundwater interception channels, permeable interception walls, and the like. For in-service industrial enterprises, due to the limitation of factors such as production operation, ground buildings and the like, the in-situ repair technology is more suitable for preventing and controlling the risk of groundwater pollution. Compared with the ectopic repair technology, the in-situ repair technology has the obvious advantages that (1) the application range is wide, and the in-situ repair technology can aim at underground water pollutants of different types, scales and depths, so that the application range is wider and more flexible. (2) The secondary pollution can be reduced, namely, in the ectopic repair technology, the treated groundwater also needs to be replaced in the natural environment, which may cause secondary pollution. In-situ remediation technology does not need to withdraw groundwater and replace the groundwater, thereby avoiding secondary pollution. (3) The in-situ remediation technology is simple to operate and convenient to maintain, and generally comprises the steps of setting relatively fewer wells and pipelines, so that the management and operation of the in-situ remediation technology are simpler and easier to implement, and the required operators are relatively fewer. (4) Compared with the ex-situ repair technology, the in-situ repair techno