Continuous supply of ultra-micron bubble water circulation well system and method for repairing groundwater

Abstract

The application discloses a circulating well system for continuously supplying ultra-micron bubble water and a method for repairing underground water, and belongs to the technical field of underground water pollution site control and repair. A circulating well is arranged in the underground water of a pollution area and is connected with the ground surface. The circulating well is sequentially provided with an upper screen section, a packer and a lower screen section from top to bottom. The upper screen section and the lower screen section are blocked by the packer. A cover is arranged on the circulating well. An upper screen pipe and a lower screen pipe are arranged on the cover. An ultra-micron bubble generator is arranged above the side of the circulating well. The ultra-micron bubble generator is communicated with the upper screen pipe and the lower screen pipe to form two circulating modes. The ultra-micron bubble water is injected into the circulating well to enhance the transmission range of the ultra-micron bubble to the underground water layer. The application provides a continuous driving force for the circulating well through the coupling of the circulating well and the ultra-micron bubble. The transmission of the ultra-micron bubble in the aquifer is enhanced. By changing the operation mode of the circulating well, NAPL phase pollutants can be synchronously and integrally treated.

Description

Technical Field

[0001] This invention relates to the field of groundwater contaminated site control and remediation technology, specifically to a circulating well system for continuously supplying ultramicron bubble water and a method for remediating groundwater. Background Technology

[0002] Numerous studies have shown that improper discharge of industrial and urban wastewater, application of agricultural chemicals, leaks from fuel storage tanks such as oil or gas, and other natural factors are the main causes of increasingly serious organic pollution in groundwater. Therefore, establishing scientifically effective groundwater remediation technologies is essential.

[0003] Traditional remediation technologies for removing organic pollutants from groundwater typically include landfill excavation and disposal, pumping, and thermal treatment. These technologies are not only costly but also cause significant disturbance to the underground environment. In contrast, in-situ groundwater remediation technology offers advantages such as high pollutant removal efficiency, short remediation cycle, and easy control of secondary pollution. It eliminates the need for groundwater extraction, significantly reducing environmental disturbance during the remediation process. Groundwater circulation wells have attracted widespread attention in recent years as an in-situ remediation technology. This technology can couple various remediation techniques, including stripping, air injection, gas-phase extraction, air aeration, bioremediation, and chemical oxidation, and holds promise for the simultaneous removal of light non-aqueous phase liquids (LNAPL), heavy non-aqueous phase liquids (DNAPL), and some inorganic substances. Circulation well remediation technology fully utilizes the space within the well to install treatment devices, effectively avoiding the high energy consumption and significant disturbance inherent in traditional extraction technologies, thus opening up new avenues for in-situ groundwater remediation.

[0004] Chinese patent CN103864263A discloses a circulating well system for removing volatile organic compounds from groundwater. This system includes an external well, an internal well, a gas extraction system, an aeration system, and a chemical spraying system. The aeration system can indirectly increase dissolved oxygen in the water. However, the bubbles generated by aeration have a particle size of over millimeters. They either break down quickly or are constrained by the movement of the water-gas two-phase flow, making them difficult to drive within the aquifer. The bubble migration distance is only 1-2 meters, and the range of oxygen carried is very limited. This restricts the maximum effectiveness of this technology throughout the aquifer.

[0005] Chinese patent CN 103145232A discloses a method and system for in-situ remediation of groundwater using micro-nano bubbles. One or more injection wells connected to the surface are set up upstream of the groundwater contamination area. A micro-nano aeration device is placed in the injection well, and the generated micro-nano bubble water enters the groundwater system by the natural flow of groundwater. Since micro-nano bubbles can provide dissolved oxygen to the groundwater environment and their negatively charged surface has an adsorption effect on pollutants, they can migrate in the groundwater environment and promote the degradation and removal of organic pollutants. However, this method can only remediate the groundwater flow area from the injection well to the pumping well, limiting the remediation range, and its remediation efficiency is low for pollutants in the soil that are difficult to be carried out by water flow.

[0006] Chinese patent CN 114751472A discloses a groundwater circulation well device and remediation method for in-situ remediation of contaminated sites, including the following steps: S1. Groundwater is pumped into the sealing layer through a groundwater pumping pipe; S2. Ozone and saponin solution are transported into the sealing layer; S3. The liquid in the sealing layer is aerated and then introduced into the groundwater and vadose zone area; S4. The liquid in the sealing layer is pumped to a groundwater treatment device for heavy metal pollutant treatment, and then the water is transported back into the sealing layer, thus completing one cycle. Then, S1-S4 are repeated for the next cycle. This circulation method is intermittent, simply pumping groundwater into the sealed layer for treatment and aeration before outputting it back into the groundwater for the next aeration treatment. Although micro-nano bubble aeration is used, this circulation method cannot continuously supply water flow. The transmission range of micro-nano bubbles is limited to the longitudinal circulation between the groundwater pumping pipes, resulting in a very limited repair range and complex operation procedures. Furthermore, the circulation well is constructed using multiple groundwater pumping pipes, circulating water between the sealed layer and the permeable layer through pumping. Its water distribution method is only on both sides of the groundwater pumping pipes, failing to achieve 360° all-round water distribution, making it difficult to achieve large-scale full circulation, resulting in weak circulation intensity and extremely low repair efficiency. Finally, it cannot flexibly select the circulation mode for different polluted areas, preventing bubbles from reaching specific areas and limiting the treatment range. Moreover, when using ozone to treat pollutants, it is easy to form sediment, clogging the pipes and resulting in high maintenance costs.

[0007] In summary, the problems with the application of circulating wells in groundwater environment remediation in existing technologies include: First, oxygen cannot reach more distant remediation areas, making the treatment of areas affected by aerobic pollutants a major challenge for site remediation; Second, because the aeration of traditional circulating wells is only affected by the circulating water flow and its own gravity, the migration of millimeter-sized bubbles generated by aeration is greatly limited. The two-phase flow law of water-air flow of millimeter-sized bubbles carrying oxygen is constrained, preventing them from penetrating long distances through the strata and limiting their ability to carry pollutants. Summary of the Invention

[0008] The purpose of this invention is to propose a circulating well system for continuously supplying ultramicron bubble water and a method for groundwater remediation. This invention effectively couples an ultramicron bubbler with a circulating well, with the ultramicron bubbler providing the driving force for the circulating well. Groundwater is pumped into the ultramicron bubbler to be prepared into ultramicron bubble water before being fed back into the circulating well. This creates a continuous driving force, generating a constant stream of ultramicron bubbles that are transported over a wide area into the groundwater environment by the circulating flow. Each time the circulating well drives a certain amount of ultramicron bubble water to migrate to the aquifer region, the ultramicron bubbles entering the aquifer region are continuously supplied, ensuring the stability of the ultramicron bubble concentration, expanding the influence range of ultramicron bubbles in the aquifer medium, increasing the possibility of interaction with pollutants, and providing a favorable remediation measure for site contamination.

[0009] One objective of this invention is to provide a circulating well system for continuously supplying ultramicron bubble water. A circulating well, connected to the surface, is installed upstream of the groundwater in a contaminated area. The circulating well contains, from top to bottom, an upper screen section, a packer, and a lower screen section. The upper and lower screen sections are separated into upper and lower areas by the packer. The wellhead of the circulating well is equipped with a cap, on which are mounted an upper screen pipe and a lower screen pipe. The lower end of the upper screen pipe is connected to the upper screen section, and the lower end of the lower screen pipe sequentially passes through the upper screen section and the packer, with the penetrating portion connecting to the lower screen section.

[0010] It also includes an ultramicron bubble generator, which is detachably connected to the upper and lower screen pipes to form two circulation modes, injecting ultramicron bubble water into the circulation well, enhancing the transmission range of ultramicron bubbles to the groundwater layer, and realizing the remediation of pollutants in the groundwater.

[0011] Preferably, in the above-mentioned circulating well system for continuously supplying ultra-micron bubble water, 360° sieve holes are arranged around both the upper and lower sieve sections, and a filter screen is arranged around the 360° sieve holes.

[0012] Preferably, in the above-mentioned circulating well system for continuously supplying ultramicron bubble water, the side wall of the ultramicron bubble generator is provided with a pressure control gauge, an air inlet, a water inlet, and a water outlet. The pressure control gauge is connected to the air inlet. The water inlet and the water outlet are detachably connected to the upper and lower screen pipes, respectively, to form two circulation modes: forward and reverse. In the forward circulation mode, the water inlet is connected to the lower screen pipe, and the water outlet is connected to the upper screen pipe. In the reverse circulation mode, the water inlet is connected to the upper screen pipe, and the water outlet is connected to the lower screen pipe.

[0013] Preferably, in the above-mentioned circulating well system for continuously supplying ultramicron bubble water, the side wall of the ultramicron bubble generator is also provided with a flow controller, the flow controller is connected to the water inlet, and the ultramicron bubble generator is also provided with a solar power supply device and a storage battery.

[0014] Preferably, in the above-mentioned circulating well system for continuously supplying ultramicron bubble water, the circulating well is further provided with a chemical injection unit. The chemical injection unit includes a chemical injection tank, two chemical injection valves, and a chemical injection pipe. The chemical injection tank is located above the cap. The lower end of the chemical injection pipe passes through the cap, the upper screen section, and the packer in sequence, with the penetration portion located above the lower screen section. The upper end of the chemical injection pipe is connected to the chemical injection tank. The two chemical injection valves are respectively provided on the chemical injection pipe, one of which is located between the upper screen section and the cap, and the other is located between the lower screen section and the packer.

[0015] Preferably, in the above-mentioned circulating well system for continuously supplying ultramicron bubble water, the circulating well is further equipped with a NAPL phase contaminant treatment device. The NAPL phase contaminant treatment device includes a processor, an exhaust gas processor, an LNAPL extraction tube, and a DNAPL extraction tube. The lower end of the LNAPL extraction tube passes through the cap and is located above the upper sieve section. The lower end of the DNAPL extraction tube passes through the cap, the upper sieve section, the packer, and the lower sieve section in sequence, and its insertion part is located below the lower sieve section. The upper ends of both the LNAPL extraction tube and the DNAPL extraction tube are connected to the processor, and the exhaust gas processor is connected to the processor.

[0016] Preferably, in the above-mentioned circulating well system for continuously supplying ultramicron bubble water, at least two monitoring wells are provided at intervals around the circulating well.

[0017] The second objective of this invention is to provide a method for repairing groundwater using the aforementioned circulating well system, comprising the following steps:

[0018] S1. A circulation well connected to the surface is set up upstream of the groundwater in the polluted area, and two monitoring wells are set up around the circulation well and in the direction of the groundwater flow in the area.

[0019] S2. Add microbial agents or emulsifiers to the injection tank and introduce them into the circulation well through the injection pipe. The inlet and outlet are detachably connected to the upper and lower screen pipes, respectively, to form two circulation modes: forward and reverse. The inlet and outlet are detachably connected to the upper and lower screen pipes, respectively. After selecting the forward or reverse circulation mode, turn on the ultramicron bubble generator. After the groundwater in the circulation well is pumped into the ultramicron bubble generator, the ultramicron bubble water generated by the pressurized gas release method is injected into the circulation well. The ultramicron bubble generator provides continuous power to the circulation well and generates ultramicron bubble water, which enhances the transmission range of ultramicron bubbles to the groundwater layer and realizes the remediation of pollutants in the groundwater.

[0020] S3. All monitoring wells are used to monitor various parameters of the circulating water in real time, including pollutant concentration, microbial population and quantity, pH value, and dissolved oxygen value, to analyze and evaluate the remediation effect and determine the degree of groundwater pollution remediation.

[0021] Preferably, in S2, the surface of the ultramicron bubbles is negatively charged, the particle size is between 0.1-1μm, and the bubble content is 84-90%.

[0022] Preferably, when the aerobic organic contamination site is contaminated, the forward circulation mode is activated; when the DNAPL site is contaminated, the forward circulation mode is activated simultaneously with the NAPL phase contaminant treatment device, and the ultramicron bubble water carries the DNAPL present below the aquifer to the circulation well in the direction of circulation flow, and extracts it through the DNAPL extraction pipe into the processor for treatment; when the LNAPL site is contaminated, the reverse circulation mode is activated, and the ultramicron bubble water carries the LNAPL present below the aquifer to the circulation well in the direction of circulation flow, and extracts it through the LNAPL extraction pipe into the processor for treatment; wherein, the tail gas of NAPL gasification is treated by the tail gas processor.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] This invention couples a circulating well with ultramicrobubbles. The ultramicrobubble generator provides the driving force for the circulating well. Groundwater is pumped into the ultramicrobubble generator to prepare ultramicrobubble water before being fed back into the circulating well. This creates a continuous driving force, generating a constant supply of ultramicrobubbles that are transported over a wide area into the groundwater environment by the circulating flow. Each time the circulating well drives a certain amount of ultramicrobubble water to migrate to the aquifer region, the ultramicrobubbles entering the aquifer region are continuously supplied, ensuring the stability of the ultramicrobubble concentration. This enables the ultramicrobubble to be transported over long distances over a wide area, providing a favorable remediation measure for site contamination, simplifying the well structure and process flow, and enhancing the transport of ultramicrobubbles in the aquifer. With the increase of circulation flow rate and circulation time, the transport range of ultramicrobubbles increases, thus overcoming the problem of traditional circulating well technology's difficulty in delivering oxygen to aquifers over long distances. By changing the operating mode of the circulating well, NAPL phase pollutants can be treated simultaneously and integrated, and the in-situ online monitoring method enables real-time monitoring of pollutant removal efficiency. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the structure of the ultramicron bubble water in-situ circulation remediation system for groundwater in Embodiment 1 of the present invention;

[0026] Figure 2 This is a schematic diagram of the structure of the ultramicron bubble generator of the present invention;

[0027] Figure 3 This is a schematic diagram of the structure of the circulating repair well system for treating aerobic organic pollution according to Embodiment 1 of the present invention;

[0028] Figure 4 This is a schematic diagram of the structure of the ultramicron bubble water in-situ circulation remediation system for groundwater in Embodiment 2 of the present invention;

[0029] Figure 5 This is a schematic diagram of the structure of the circulating remediation well system for treating DNAPL phase contaminants in Embodiment 2 of the present invention;

[0030] Figure 6 This is a schematic diagram of the structure of the circulating repair well system for treating LNAPL phase contaminants in Embodiment 2 of the present invention;

[0031] Explanation of reference numerals in the attached figures:

[0032] 1. Fixed structure; 11. Solar power supply device; 12. Pressure gauge; 13. Air inlet; 14. Flow meter; 15. Water inlet; 16. Water outlet; 2. Circulation well; 21. Cover; 22. Upper screen pipe; 23. Upper screen section; 24. Lower screen pipe; 25. Packer; 26. Lower screen section; 3. Chemical injection unit; 31. Chemical injection tank; 32. Chemical injection pipe valve; 33. Chemical injection pipe; 4. NAPL phase pollutant treatment device; 41. Processor; 42. Exhaust gas processor; 43. NAPL extraction pipe; 44. DNAPL extraction pipe; 51. Monitoring well. Detailed Implementation

[0033] To enable those skilled in the art to better understand and implement the technical solutions of this invention, the invention will be further described below with reference to specific embodiments and accompanying drawings. The described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0034] Example 1

[0035] A circulating well system for continuously supplying ultramicron bubble water, such as Figure 1-2 As shown, a circulation well 2 connected to the surface is set up upstream of the groundwater in the contaminated area. The circulation well 2 is used to provide space for the groundwater remediation process. The circulation well 2 is provided with an upper screen section 23, a packer 25 and a lower screen section 26 from top to bottom. The upper screen section 23 and the lower screen section 26 are separated into two areas by the packer 25. The packer 25 divides the circulation well 2 into an upper half area and a lower half area. The wellhead of the circulation well 2 is provided with a cover 21. The cover 21 is provided with an upper screen pipe 22 and a lower screen pipe 24. The lower end of the upper screen pipe 22 is connected to the upper screen section 23. The lower end of the lower screen pipe 24 passes through the upper screen section 23 and the packer 25 in sequence, and the part that passes through it is connected to the lower screen section 26.

[0036] It also includes an ultramicron bubble generator 1, which is located above the groundwater level. The ultramicron bubble generator 1 is detachably connected to the upper screen pipe 22 and the lower screen pipe 24 to form two circulation modes, forward and reverse. By selecting different circulation modes, the ultramicron bubble generator 1 is turned on to provide power for the circulation of groundwater in the circulation well 2. It can also convert the pumped groundwater into ultramicron bubble water and then inject it into the circulation well 2. The circulation well 2 can achieve the enrichment of ultramicron bubbles in the aquifer medium, providing continuous driving force for the circulation well 2 and generating ultramicron bubble water. The circulation well 2 can transport the generated ultramicron bubble water to a more distant area, achieving a 1+1 greater than 2 effect, enhancing the transmission range of ultramicron bubbles to the groundwater layer, and realizing the remediation of pollutants in the groundwater.

[0037] The upper sieve section 23 and the lower sieve section 26 are both surrounded by 360° sieve holes, and a filter screen is arranged around the 360° sieve holes to prevent clogging.

[0038] The ultramicron bubble generator 1 has a pressure control gauge 12, an air inlet 13, a water inlet 15, and a water outlet 16 on its side wall. The pressure control gauge 12 is connected to the air inlet 13, and a pressure valve is located below the pressure control gauge 12, connected to the air inlet 13. By rotating the pressure valve, the pressure of the pressure control gauge 12 can be observed to adjust the air intake of the air inlet 13. The air inlet 13 can select air, oxygen, ozone, hydrogen, etc., according to the needs of different contaminated sites. The water inlet 15 and the water outlet 16 are detachably connected to the upper screen tube 22 and the lower screen tube 24, respectively, forming two circulation modes: forward and reverse. Specifically, each of the water inlet 15 and the water outlet 16 has a connector, and the upper screen tube 22 and the lower screen tube 24 are connected to the connector to form a detachable connection. The water inlet 15 and the water outlet 16 are respectively connected to the upper screen tube 22 and the lower screen tube 24 to form a detachable connection. The upper screen pipe 22 and the lower screen pipe 24 are connected in a corresponding plug-in manner, changing the connection method between the inlet 15, the outlet 16, and the upper screen pipe 22 and the lower screen pipe 24. In the forward circulation mode, the inlet 15 is plugged into the lower screen pipe 24, and the outlet 16 is plugged into the upper screen pipe 22. The inlet 15 can pump groundwater from the circulation well 2 into the ultramicron generator 1. The outlet 16 can process the pumped groundwater into ultramicron bubble water through the ultramicron generator and inject it into the circulation well 2, providing continuous driving force for the circulation well 2 and achieving ultramicron bubble enrichment in the upper half of the aquifer medium around the circulation well 2. In the reverse circulation mode, the inlet 15 is plugged into the upper screen pipe 22, and the outlet 16 is plugged into the lower screen pipe 24, achieving ultramicron bubble enrichment in the lower half of the aquifer medium around the circulation well 2.

[0039] The ultramicron bubble generator 1 is also equipped with a flow meter 14 on its side wall. The flow meter 14 is connected to the inlet 15. A flow valve is located below the flow meter 14 and is also connected to the inlet 15. By rotating the flow valve and observing the flow rate of the flow meter 14, the water flow rate at the inlet 15 can be adjusted. Increasing the water flow rate of the ultramicron bubble generator 1 can increase the transmission range of the ultramicron bubbles and expand the remediation range of pollutants. Increasing the flow rate of the ultramicron bubble device 1 increases the influence radius of the ultramicron bubbles in the circulation well, with the main well unit of the circulation well 2 as the center. The larger the flow rate of the ultramicron bubble device 1, the larger its influence radius. The ultramicron bubble generator 1 is also equipped with a solar power supply device 11 and a battery. The solar power supply device 11 and the battery provide power to the ultramicron bubble generator, which has low maintenance costs and stable operation. It has a strong advantage, especially in large-scale contaminated sites or field sites where power supply is difficult.

[0040] The circulating well 2 is also equipped with a chemical injection unit 3 for adding emulsifiers or aerobic microbial agents, which can be used to add different agents for different pollutants. The chemical injection unit 3 includes an injection tank 31, two injection pipe valves 32, and an injection pipe 33. The injection tank 31 is located above the cover 21. The lower end of the injection pipe 33 passes through the cover 21, the upper screen section 23, and the packer 25 in sequence, and the part that passes through is located above the lower screen section 26. The upper end of the injection pipe 33 is connected to the injection tank 31. The two injection pipe valves 32 are respectively provided on the injection pipe 33. One injection pipe valve 32 is located between the upper screen section 23 and the cover 21, and the other injection pipe valve 32 is located between the lower screen section 26 and the packer 25.

[0041] For sites with aerobic organic pollution, the dosing tank 31 can add aerobic biological agents. With continuous injection of these agents, they are transported to the aquifer medium via the circulating ultramicron bubble water flow, significantly increasing the degradation efficiency and scope of aerobic pollutants. Preferably, the aerobic biological agents include Bacillus, Pseudomonas, Lactobacillus, Nitrosinophils, Nitrifying Bacillus, biological enzymes, and nutrients. These agents can detoxify and shield toxic substances in the water, while simultaneously stimulating beneficial aerobic bacteria to decompose organic matter in the wastewater, promoting microbial reproduction, enhancing the microbial capacity for oxidative decomposition of pollutants, and improving the overall resistance of microorganisms in the water.

[0042] At least two monitoring wells 51 are arranged at intervals around the circulation well 2. Two monitoring wells 51 are arranged around the circulation well 2 and in the direction of groundwater flow in the area. Water quality monitoring probes are installed at the bottom of the monitoring wells 51 to monitor various indicators and parameters in real time, including pollutant concentration, microbial population and quantity, pH value, dissolved oxygen value, etc., to scientifically analyze and evaluate the remediation effect and determine the degree of remediation of groundwater pollution.

[0043] Methods for restoring groundwater using the aforementioned circulating well system, such as Figure 3 As shown, it includes the following steps:

[0044] S1. For aerobic organic pollution sites, a circulation well 2 connected to the surface is set up upstream of the groundwater in the pollution area, and two monitoring wells 51 are set up around the circulation well 2 and in the direction of groundwater flow in the area.

[0045] S2. Add microbial agent to the injection tank 31 and enter the circulation well 2 through the injection pipe 33. Turn on the ultramicron bubble generator 1. Increase the flow rate of the inlet and outlet water 15 through the flow controller 14 to change the influence radius of the ultramicron bubble water. Control the air pressure of the air inlet 13 to provide oxygen or oxygen to the microorganisms. Select the forward circulation mode. Connect the inlet 15 to the lower screen pipe 24 and the outlet 16 to the upper screen pipe 22. Start the ultramicron bubble generator 1. After the groundwater in the circulation well 2 is pumped into the ultramicron bubble generator 1, the ultramicron bubble water generated by the pressurized gas release method is injected into the top of the packer 25 in the circulation well 2 to achieve the enrichment of ultramicron bubbles in the aquifer medium around the upper part of the circulation well 2.

[0046] Groundwater in circulation well 2 is pumped into ultramicron bubble generator 1 through inlet 15 to prepare ultramicron bubble water, and then fed back into circulation well 2 through outlet 16. This creates a continuous driving force, generating a continuous stream of ultramicron bubbles that are transported over a wide area to the groundwater environment by the circulation flow. With each flow, circulation well 2 drives a certain amount of ultramicron bubble water to migrate to the aquifer area. This ensures a continuous supply of ultramicron bubbles entering the aquifer area, maintaining the stability of the ultramicron bubble concentration, expanding the influence range of ultramicron bubbles in the aquifer medium, and increasing the possibility of interaction and treatment with pollutants. Circulation well 2 can transport the generated ultramicron bubble water to a more distant area, achieving a 1+1 effect that is far greater than 2. A three-dimensional circulating ultramicron bubble water flow field is formed in the aquifer outside circulation well 2.

[0047] The surface of ultramicro bubbles is negatively charged, with a particle size between 0.1-1μm and a bubble content of 84-90%. They have a large specific surface area and can enhance the mass transfer process between the gas phase, water phase and pollutant phase in the groundwater remediation process, thereby improving the pollutant removal efficiency.

[0048] The flow controller 14 increases the transmission range of the ultramicron bubbles, thereby increasing the remediation range of pollutants. The microbial agent enters the groundwater environment with the ultramicron bubble circulation flow. The ultramicron bubble water provides a sufficient oxygen environment for the aerobic biological agent, promoting its rapid growth. Furthermore, it can be transported to a large area of ​​contaminated sites with the circulation flow, greatly increasing the degradation efficiency and range of aerobic pollutants.

[0049] S3. All monitoring wells 51 are used to monitor various parameters of the water in circulating well 2 in real time, including pollutant concentration, microbial population and quantity, pH value, and dissolved oxygen value. The remediation effect is analyzed and evaluated to determine the degree of remediation of groundwater pollution.

[0050] Example 2

[0051] A circulating well system for continuously supplying ultramicron bubble water, basically as described in Example 1, such as... Figure 4-5 As shown, the difference is:

[0052] The circulating well 2 is also equipped with a NAPL phase pollutant treatment device 4. The NAPL phase pollutant treatment device 4 includes a processor 41, an exhaust gas processor 42, an LNAPL extraction tube 43, and a DNAPL extraction tube 44. The lower end of the LNAPL extraction tube 43 passes through the cap 21 and the insertion part is located above the upper sieve section 23. The lower end of the DNAPL extraction tube 44 passes through the cap 21, the upper sieve section 23, the packer 25, and the lower sieve section 26 in sequence, and the insertion part is located below the lower sieve section 26. The upper ends of the LNAPL extraction tube 43 and the DNAPL extraction tube 44 are both connected to the processor 41. The exhaust gas processor 42 is connected to the processor 41.

[0053] In cases of NAPL site contamination, the injection tank 31 can add different emulsifiers to assist ultramicron bubbles in efficiently emulsifying NAPL phase contaminants. These emulsifiers can be surfactants with an HLB value (hydrophilic-lipophilic balance) between 10 and 18. Depending on the characteristics of the NAPL phase contaminants: if the NAPL contaminants are negatively charged, a cationic surfactant with an HLB value between 10 and 18 is selected, with dodecyltrimethylammonium chloride being a better choice; if the NAPL contaminants are positively charged, an anionic surfactant with an HLB value between 10 and 18 is selected, with sodium dodecyl sulfonate being a better choice; if the NAPL contaminants are non-electrolyte, a nonionic surfactant with an HLB value between 10 and 18 is selected, with emulsifier OP-10 being a better choice. Adopting different circulation methods for different contaminants can effectively increase treatment efficiency and reduce remediation costs.

[0054] The method for restoring groundwater using the above-mentioned circulating well system is basically the same as Example 1, with the difference being:

[0055] S2. In the case of DNAPL site contamination, select the forward circulation mode, connect the inlet 15 to the lower screen pipe 24, connect the outlet 16 to the upper screen pipe 22, start the ultramicro bubble generator 1, and simultaneously turn on the NAPL phase pollutant treatment device 4. Under the action of circulating water, the ultramicro bubble water output from the circulating well 2 applies a downward driving force to the DNAPL site, so that the ultramicro bubble water can quickly and effectively migrate and carry the DNAPL present below the aquifer to the main well of the circulating well 2 in the direction of circulation flow. Since the density of DNAPL is greater than that of water, it will be located at the bottom of the lower screen section of the circulating well. Under the action of the DNAPL extraction pipe 44, it is extracted and sent to the processor 41 for processing. The tail gas of DNAPL vaporization after ultramicro bubble aeration can be directly extracted into the tail gas processor 42 for processing.

[0056] In the case of LNAPL site contamination, the reverse circulation mode is selected. The inlet 15 is connected to the upper screen pipe 22, and the outlet 16 is connected to the lower screen pipe 24. The ultramicron bubble generator 1 is started, and the NAPL phase pollutant treatment device 4 is turned on at the same time. Under the action of circulating hydraulic stimulation, the ultramicron bubble water output from the circulation well applies an upward driving force to the LNAPL site, so that the ultramicron bubble water can quickly and effectively migrate and carry the LNAPL below the aquifer to the main well of the circulation well in the direction of circulation flow. Since the density of LNAPL is less than that of water, it will be located at the top of the upper screen section of the circulation well. Under the action of LNAPL extraction pipe 43, it is extracted and sent to processor 41 for processing. The tail gas of LNAPL gasification after ultramicron bubble aeration can be directly extracted into tail gas treatment unit 42 for treatment.

[0057] This invention provides a continuous driving force for the circulation well by coupling it with ultramicrobubbles, simplifying the well structure and process flow, and enhancing the transport of ultramicrobubbles in the aquifer. With increasing circulation flow rate and circulation time, the transport range of ultramicrobubbles increases, thus overcoming the problem of traditional circulation well technology's difficulty in delivering oxygen to the aquifer over long distances. By changing the operation mode of the circulation well, NAPL phase pollutants can be treated simultaneously and in an integrated manner, and the in-situ online monitoring method enables real-time monitoring of pollutant removal efficiency.

[0058] It should be noted that the connection relationships of components not specifically mentioned in this invention are all assumed to be based on existing technology. Since they do not involve the inventive point and are commonly used in existing technology, the structural connection relationships are not described in detail.

[0059] It should be noted that when numerical ranges are involved in this invention, it should be understood that both endpoints of each numerical range and any value between the two endpoints can be selected. Since the steps and methods used are the same as in the embodiments, preferred embodiments are described here to avoid redundancy. Although preferred embodiments of the invention have been described, those skilled in the art, once they understand the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this invention.

[0060] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A circulating well system for continuously supplying ultramicron bubble water, wherein a circulating well (2) connected to the surface is set up upstream of the groundwater in a polluted area, characterized in that, The circulation well (2) is provided with an upper screen section (23), a packer (25) and a lower screen section (26) from top to bottom. The upper screen section (23) and the lower screen section (26) are separated into upper and lower areas by the packer (25). The wellhead of the circulation well (2) is provided with a cover (21). The cover (21) is provided with an upper screen pipe (22) and a lower screen pipe (24). The lower end of the upper screen pipe (22) is connected to the upper screen section (23). The lower end of the lower screen pipe (24) passes through the upper screen section (23) and the packer (25) in sequence, and the part that passes through is connected to the lower screen section (26). It also includes an ultramicron bubble generator (1), which is detachably connected to the upper screen pipe (22) and the lower screen pipe (24) to form two circulation modes, injecting ultramicron bubble water into the circulation well (2) to enhance the transmission range of ultramicron bubbles to the groundwater layer and realize the remediation of pollutants in the groundwater. The side wall of the ultramicron bubble generator (1) is provided with a pressure control gauge (12), an air inlet (13), a water inlet (15), and a water outlet (16). The pressure control gauge (12) is connected to the air inlet (13). The water inlet (15) and the water outlet (16) are detachably connected to the upper screen tube (22) and the lower screen tube (24) respectively to form two circulation modes: forward and reverse. In the forward circulation mode, the water inlet (15) is connected to the lower screen tube (24), and the water outlet (16) is connected to the upper screen tube (22). In the reverse circulation mode, the water inlet (15) is connected to the upper screen tube (22), and the water outlet (16) is connected to the lower screen tube (24). The side wall of the ultramicron bubble generator (1) is also provided with a flow controller (14), which is connected to the water inlet (15).

2. The circulating well system for continuously supplying ultra-micron bubble water according to claim 1, characterized by, The upper sieve section (23) and the lower sieve section (26) are both surrounded by 360° sieve holes, and a filter screen is arranged around the 360° sieve holes.

3. The circulating well system for continuously supplying ultra-micron bubble water according to claim 2, characterized by, The ultramicron bubble generator (1) is also equipped with a solar power supply device (11) and a storage battery.

4. The circulating well system for continuously supplying ultra-micron bubble water according to claim 3, characterized by, The circulating well (2) is also equipped with a drug injection unit (3). The drug injection unit (3) includes a drug injection tank (31), two drug injection pipe valves (32), and a drug injection pipe (33). The drug injection tank (31) is located above the cap (21). The lower end of the drug injection pipe (33) passes through the cap (21), the upper screen section (23), and the packer (25) in sequence, and the part that passes through is located above the lower screen section (26). The upper end of the drug injection pipe (33) is connected to the drug injection tank (31). The two drug injection pipe valves (32) are respectively located on the drug injection pipe (33). One of the drug injection pipe valves (32) is located between the upper screen section (23) and the cap (21), and the other drug injection pipe valve (32) is located between the lower screen section (26) and the packer (25).

5. The circulating well system for continuously supplying ultra-micron bubble water according to claim 4, characterized by, The circulating well (2) is also equipped with a NAPL phase pollutant treatment device (4). The NAPL phase pollutant treatment device (4) includes a processor (41), an exhaust gas processor (42), an LNAPL extraction tube (43), and a DNAPL extraction tube (44). The lower end of the LNAPL extraction tube (43) passes through the cap (21), and the insertion part is located above the upper sieve section (23). The lower end of the DNAPL extraction tube (44) passes through the cap (21), the upper sieve section (23), the packer (25), and the lower sieve section (26) in sequence, and the insertion part is located below the lower sieve section (26). The upper ends of the LNAPL extraction tube (43) and the DNAPL extraction tube (44) are both connected to the processor (41). The exhaust gas processor (42) is connected to the processor (41).

6. The circulating well system for continuously supplying ultra-micron bubble water according to claim 5, wherein At least two monitoring wells (51) are spaced around the circulation well (2).

7. A method of remediating groundwater using the cycled well system of claim 6, wherein, Includes the following steps: S1. A circulation well (2) connected to the surface is set up upstream of the groundwater in the polluted area, and two monitoring wells (51) are set up around the circulation well (2) and in the direction of the groundwater flow in the area. S2. Add microbial agents or emulsifiers to the injection tank (31) and enter the circulation well (2) through the injection pipe (33). The inlet (15) and outlet (16) are respectively connected to the upper screen pipe (22) and lower screen pipe (24) to form two circulation modes, one forward and one reverse. The inlet (15) and outlet (16) are respectively connected to the upper screen pipe (22) and lower screen pipe (24) to form two circulation modes, one forward and one reverse. After selecting the forward and reverse circulation modes, turn on the ultramicron bubble generator (1). After the groundwater in the circulation well (2) is pumped into the ultramicron bubble generator (1), the ultramicron bubble water generated by the pressurized gas release method is injected into the circulation well (2). The ultramicron bubble generator (1) provides continuous power to the circulation well (2) and generates ultramicron bubble water, which enhances the transmission range of ultramicron bubbles to the groundwater layer and realizes the remediation of pollutants in the groundwater. S3. Use all monitoring wells (51) to monitor the various parameters of the water in the circulating well (2) in real time, analyze and evaluate the remediation effect, and judge the degree of remediation of groundwater pollution.

8. The method for restoring groundwater using a circulating well system according to claim 7, characterized in that, In S2, the surface of the ultramicron bubbles is negatively charged, and their particle size is between 0.1-1μm, with a bubble content of 84-90%.

9. The method for restoring groundwater using a circulating well system according to claim 8, characterized in that, In S2, when the aerobic organic pollutant field is polluted, the forward circulation mode is selected; when the DNAPL field is polluted, the forward circulation mode is selected and the NAPL phase pollutant treatment device (4) is turned on at the same time. The ultra-micro bubble water carries the DNAPL present below the aquifer to the circulation well (2) in the direction of circulation flow, and extracts it through the DNAPL extraction pipe (44) into the processor (41) for treatment. When the LNAPL site is contaminated, the reverse circulation mode is selected. The ultra-micron bubble water carries the LNAPL existing below the aquifer into the circulation well (2) in the direction of circulation flow. Under the action of the LNAPL extraction pipe (43), it is extracted and sent to the processor (41) for processing. The tail gas of NAPL gasification is processed by the tail gas processor (42).

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