In-situ soil and groundwater remediation device and method using membrane contact electro-catalytic oxidation

Abstract

This invention discloses a membrane contact electrocatalytic oxidation in-situ soil and groundwater remediation device, comprising: multiple underground well pipes installed in the remediation area for gas transport and catalytic reaction; multiple pumping wells for extracting groundwater contaminated by organic pollutants in the soil; injection wells for reinjecting treated clean water into the aquifer; and multiple monitoring wells for testing water samples after wastewater treatment to evaluate the remediation effect and water quality changes. This invention also discloses a membrane contact electrocatalytic oxidation in-situ remediation method for organic polluted groundwater. This invention alleviates the problem of oxidant self-decomposition by continuously generating strong oxidant H2O2 liquid in the underground well pipes during the electrocatalytic process. The pressure of the continuously input original gas drives the H2O2 liquid into the remediation area, causing rapid oxidation of oxides in the wastewater.

Description

Technical Field

[0001] This invention belongs to the field of wastewater treatment technology, specifically a membrane contact electrocatalytic oxidation device and method for in-situ remediation of soil and groundwater. Background Technology

[0002] Traditional in-situ chemical oxidation technologies typically involve injecting liquid oxidants or adding solid oxidants. However, due to the uneven distribution of soil media and slow groundwater flow at contaminated sites, the migration distance of oxidants in these technologies is limited. Furthermore, the rapid reaction rate and short lifespan of oxidants often necessitate the establishment of numerous application points and repeated additions. In addition, the traditional methods of oxidant addition can lead to excessively high concentrations at application points, causing violent reactions that release large amounts of gas and heat, ultimately resulting in significant oxidant self-decomposition. Therefore, traditional in-situ chemical oxidation technologies face numerous challenges, including limited oxidant migration distance, short lifespan, and severe oxidant self-decomposition.

[0003] Therefore, a membrane contact electrocatalytic oxidation device and method are provided for in-situ remediation of soil and groundwater. Summary of the Invention

[0004] To address the aforementioned problems in the existing technology, this invention provides a membrane contact electrocatalytic oxidation device and method for in-situ remediation of soil and groundwater. By continuously generating strong oxidant H2O2 liquid in the underground well pipe during the electrocatalytic process, excessively high local oxidant concentrations are avoided, alleviating the problem of oxidant self-decomposition. Furthermore, the pressure of the continuously input raw gas drives the H2O2 liquid into the remediation zone, achieving the purpose of rapid oxidation of oxides in wastewater.

[0005] The technical solution to achieve the above objectives is: One of the inventions is a membrane contact electrocatalytic oxidation in-situ soil and groundwater remediation device, comprising: Multiple underground wells for gas transport and catalytic reactions are installed in the remediation area; Multiple pumping wells were installed in the remediation area to extract groundwater contaminated by organic pollutants in the soil; Water injection wells used for reinjecting treated clean water into aquifers; and Multiple monitoring wells were set up in the remediation area for testing water samples after wastewater treatment to assess the remediation effect and water quality changes; in, The underground well pipe is equipped with an electrode pipe for fixing the anode structure. The electrode pipe is equipped with a PU gas pipe for transporting raw gas to the catalytic reaction zone. The PU gas pipe is equipped with an aeration needle for breaking the transported gas into microbubbles to increase the gas-liquid contact area. The PU gas tube has multiple first through holes on its sidewall. The side of the first through hole near the electrode tube is wrapped with a membrane cathode for reducing the transported gas into H2O2 liquid. The electrode tube has multiple second through holes on its sidewall. A conductive anode is arranged around the side of the second through holes near the PU gas tube to generate active hydroxyl radicals to directly oxidize organic matter after energization. The membrane cathode and the conductive anode work together to oxidize and degrade pollutants. The pumping well is equipped with a sewage treatment component, and the output end of the sewage treatment component is located in the injection well. The three adjacent underground well pipes are arranged in an equilateral triangle, and each pumping well is symmetrically arranged on both sides of an injection well.

[0006] Preferably, the underground well pipe is a PVC pipe with a 200-mesh high-density nylon screen.

[0007] Preferably, the wastewater treatment component includes: a pumping pipe, The input end of the pumping pipe with multiple first filter holes is placed inside the pumping well, and the output end of the pumping pipe is placed inside the injection well. The outer side of the pumping pipe with the first filter hole is slidably sealed with a sleeve, and the sleeve has multiple second filter holes. The bottom of the outer wall of the pumping pipe is connected to a protective pipe via a first mounting ring. A first spring is installed inside the protective pipe. The bottom of the first spring is connected to the first mounting ring, and the top of the spring is connected to the bottom of the sleeve. The sleeve and the protective pipe are slidably connected. The top of the sleeve is provided with a first oblique crown tooth, which is connected to the vibration component.

[0008] Preferably, the vibration assembly includes: a second oblique crown tooth and a first motor disposed on the outer wall of the pumping pipe; The bottom of the second oblique crown tooth is located below the top of the first oblique crown tooth, and the oblique surface of the second oblique crown tooth slides in engagement with the oblique surface of the first oblique crown tooth; The top of the second oblique crown tooth is connected to the bottom of the first mounting tube; The top inner wall of the first mounting tube is rotatably connected to the outer wall of the second mounting tube, and a drive assembly is provided on the outer wall of the first mounting tube. The inner wall of the second mounting pipe is slidably connected to the outer wall of the pumping pipe, and a cleaning component is provided at the top of the outer wall of the second mounting pipe; The top of the second mounting tube is connected to the bottom of the second spring via a second mounting ring; The top of the second spring is connected to the water suction pipe; The second mounting ring is provided with two first push blocks at the top, and the top of the first push block is provided with a first chamfer, which is set towards the side wall of the water pipe; The output end of the first motor is connected to one end of the first rotating shaft, and the first rotating shaft passes through the side wall of the water pumping pipe and is connected to the first helical gear; The first helical gear meshes with the second helical gear, and a screw is connected to each end of the second helical gear; Each threaded portion of the screw is connected to a threaded tube, which is slidably connected to the water pumping pipe. A second push block is connected to the end of the threaded tube outside the water pumping pipe. The second chamfer at the bottom of the second push block is in frictional engagement with the first chamfer.

[0009] Preferably, the drive assembly includes: a toothed ring mounted on the outer wall of the first mounting pipe, and a second motor mounted on the outer wall of the pumping pipe, the second motor being disposed opposite to the toothed ring; The gear ring meshes with the gear, and the top of the gear is rotatably connected to the first fixing rod fixed on the outer wall of the pumping pipe via a second rotating shaft; The second rotating shaft passes through the top of the first fixed rod and connects to the first crown tooth. The first crown tooth meshes with the first cylindrical tooth. The first cylindrical tooth passes through the side wall of the pumping pipe via the third rotating shaft and connects to the output end of the second motor. The third rotating shaft placed inside the water pumping pipe is provided with a second cylindrical tooth, which meshes with a second crown-shaped tooth; The bottom of the second crown-shaped tooth is connected to the top of the fourth rotating shaft, and the fourth rotating shaft is rotatably connected to the second fixed rod fixed to the inner side wall of the pumping pipe. The bottom of the fourth rotating shaft is connected to the blade.

[0010] Preferably, the cleaning assembly includes: multiple push rods, The top of the push rod is connected to the top of the outer wall of the second mounting tube; The bottom of the push rod is connected to the top of the output tube; The bottom opening of the output tube faces the second filter hole, the outer wall of the output tube is slidably connected to the longitudinal tube, and the side wall of the longitudinal tube is connected to the inner wall of the annular tube through a pipe. The output pipe has a waist-shaped hole on the side near the annular pipe, and the waist-shaped hole is located above the top wall of the pipe; The end of the water inlet pipe is connected to the side wall of the annular pipe. The water inlet pipe is connected to a pressure relief valve and a water pump. The other end of the water inlet pipe is placed on the ground and connected to a water storage tank.

[0011] The second invention relates to a membrane contact electrocatalytic oxidation in-situ soil and groundwater remediation device, comprising: Step S1: Install multiple underground well pipes within the repair area; Step S2: Wrap the membrane cathode around the first through hole of the PU gas pipe and surround the conductive anode around the second through hole of the electrode pipe, and install the electrode pipe, PU gas pipe and aeration needle inside the underground well pipe; Step S3: Supply raw gas to the underground well pipe via the gas supply pipe; Step S4: After supplying raw gas to the underground well pipe, connect the conductive anode and membrane cathode in the underground well pipe to the positive and negative terminals of the power supply, respectively. Step S5: Catalyze the original gas using the potential difference formed between the conductive anode and the membrane cathode; Step S6: After catalysis, H2O2 liquid is obtained. The H2O2 liquid enters the remediation area through the underground well pipe to oxidize the organic matter in the sewage in the remediation area. The sewage is groundwater contaminated by organic pollutants in the soil of the remediation area (4). Step S7: After the sewage is treated by the underground well pipe, a plurality of the pumping wells and injection wells are set in the repair area. The sewage treatment components are installed in the pumping wells and connected to the injection wells. Step S8: The wastewater treatment component uses the oxidant discharged from the underground well pipe to treat the remaining organic matter in a unified manner. Step S9: After a period of sewage treatment, multiple monitoring wells are set up in the remediation area. Groundwater is extracted from the remediation area through the monitoring wells and tested by machine until the remediation is completed.

[0012] Preferably, in step S2, before supplying raw gas to the underground well pipe, the end of a hose with a blower is connected to the top of the aeration needle, and then the other end of the hose is connected to the raw gas storage tank. Then, a sealing plate is used to seal the underground well pipe and the hose.

[0013] Preferably, in step S3, the original gas is O2, or O3, or a mixture of O2 and O3.

[0014] Compared with the prior art, the beneficial effects of the present invention are: In this invention, the potential difference between the conductive anode and the membrane cathode is used to catalyze the original gas, resulting in H2O2 liquid. The H2O2 liquid enters the remediation zone through the electrode well to oxidize the organic matter in the groundwater contaminated by organic pollutants in the soil. By continuously generating strong oxidant H2O2 liquid in the underground well during the electrocatalytic process, excessively high local oxidant concentrations are avoided, alleviating the problem of oxidant self-decomposition. The pressure of the continuously input original gas drives the H2O2 liquid into the remediation zone, achieving the purpose of rapid oxidation of oxides in wastewater, thereby achieving the remediation of soil pollution. In this invention, after the underground well pipe finishes treating the sewage, some organic matter will still remain in the groundwater. At this time, the pumping well will pump out the treated sewage near the underground well pipe and re-inject it into the upstream of the underground well pipe through the sewage treatment components in the injection well. After the water flows, the oxidant discharged from the underground well pipe will be used again to uniformly treat the remaining organic matter, thereby improving the efficiency of sewage treatment. In this invention, by setting up monitoring wells, the groundwater in the remediation area can be tested on the machine to accurately determine in real time whether the oxides have been completely oxidized, thereby reducing the waste of oxidant. Attached Figure Description

[0015] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings: Figure 1 This is a top view of the repair area of ​​the present invention; Figure 2 This is a schematic diagram of the electrode tube, PU air tube, and aeration needle structure of the membrane contact electrocatalytic oxidation in-situ soil and groundwater remediation device of the present invention. Figure 3 This is a cross-sectional view of the inside of the electrode tube in this invention; Figure 4 This is a partial structural diagram of the wastewater treatment component in this invention; Figure 5 This is another structural diagram of the wastewater treatment component in this invention; Figure 6 This is another structural diagram of the wastewater treatment component in this invention; Figure 7 This is a partial structural diagram of the vibration component in the wastewater treatment assembly of the present invention; Figure 8 This is another structural diagram of the vibration component in the wastewater treatment assembly of the present invention; Figure 9 This is another structural diagram of the vibration component in the wastewater treatment assembly of the present invention; Figure 10 This is another structural diagram of the vibration component in the wastewater treatment assembly of the present invention; Figure 11 This is a structural diagram of the drive component in the wastewater treatment assembly of the present invention; Figure 12 This is a structural diagram of another part of the drive component in the wastewater treatment assembly of the present invention; Figure 13 This is a structural diagram of the cleaning component in the wastewater treatment assembly of the present invention; Figure 14 This is a structural diagram of another part of the cleaning component in the wastewater treatment assembly of the present invention; Figure 15 This is a flowchart of the membrane contact electrocatalytic oxidation method for in-situ remediation of soil and groundwater according to the present invention. Detailed Implementation

[0016] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0017] like Figure 1-3 As shown, the membrane contact electrocatalytic oxidation in-situ soil and groundwater remediation device includes: multiple underground well pipes 1 installed in the remediation zone 4 for gas transport and catalytic reaction; an electrode pipe 6 for fixing the anode structure is installed inside the underground well pipe 1; a PU gas pipe 7 for transporting raw gas to the catalytic reaction zone is installed inside the electrode pipe 6; an aeration needle 8 for breaking the transported gas into microbubbles to increase the gas-liquid contact area is installed inside the PU gas pipe 7; multiple first through holes 9 are opened on the side wall of the PU gas pipe 7; a membrane cathode 11 for reducing the transported gas to H2O2 liquid is wrapped around the side of the first through hole 9 near the electrode pipe 6; multiple second through holes 10 are opened on the side wall of the electrode pipe 6; a conductive anode 12 for generating active hydroxyl radicals to directly oxidize organic matter after energization is arranged around the side of the second through hole 10 near the PU gas pipe 7; the membrane cathode 11 and the conductive anode 12 synergistically oxidize and degrade pollutants. Multiple pumping wells 2 are installed in the remediation area 4 to extract groundwater contaminated by organic pollutants in the soil (hereinafter referred to as sewage), and multiple injection wells 3 are installed in the remediation area 4 to reinject the treated clean water back into the aquifer; the pumping wells 2 are equipped with sewage treatment components, and the output end of the sewage treatment components is placed in the injection wells 3. Multiple monitoring wells 5 are set up in the remediation area 4 for testing water samples after sewage treatment to assess the remediation effect and water quality changes; in, The three adjacent underground well pipes 1 are arranged in an equilateral triangle. Each pumping well 2 is symmetrically arranged on both sides of an injection well 3, as shown below. Figure 1 As shown.

[0018] In this embodiment, the underground well pipe 1 is a PVC pipe with a 200-mesh high-density nylon screen.

[0019] In this embodiment, the membrane cathode 11 is composed of a carbon-containing conductive material and a porous hydrophobic layer, wherein the carbon-containing conductive material is any one of carbon cloth, carbon felt, or carbon fiber, and the porous hydrophobic layer is polytetrafluoroethylene; the conductive anode 12 is any one of a titanium plate or a titanium plate with a ruthenium or iridium coating.

[0020] like Figure 4-6 As shown, the wastewater treatment assembly includes: a pumping pipe 13, the input end of which has multiple first filter holes 14 is placed inside a pumping well 2, and the output end of which is placed inside an injection well 3; a sleeve 15 is slidably and sealingly connected to the outer side of the pumping pipe 13 with the first filter holes 14, and multiple second filter holes 16 are opened on the sleeve 15; a protective pipe 17 is connected to the bottom of the outer wall of the pumping pipe 13 through a first mounting ring, and a first spring 51 is provided inside the protective pipe 17, the bottom of the first spring 51 is connected to the first mounting ring, the top of the spring 51 is connected to the bottom of the sleeve 15, and the sleeve 15 and the protective pipe 17 are slidably connected; a first oblique crown tooth 18 is provided on the top of the sleeve 15 and is connected to a vibration assembly.

[0021] like Figure 4 , 7As shown in Figure -10, the vibration assembly includes: a second oblique crown tooth 19 and a first motor 26 disposed on the outer wall of the pumping pipe 13; the bottom of the second oblique crown tooth 19 is disposed below the top of the first oblique crown tooth 18, and the oblique surface of the second oblique crown tooth 19 slides in engagement with the oblique surface of the first oblique crown tooth 18; the top of the second oblique crown tooth 19 is connected to the bottom of the first mounting tube 20; the inner side wall of the top of the first mounting tube 20 is rotatably connected to the outer side wall of the second mounting tube 21, and a driving assembly is disposed on the outer side wall of the first mounting tube 20; the inner side wall of the second mounting tube 21 is slidably connected to the outer side wall of the pumping pipe 13, and a cleaning assembly is disposed at the top of the outer side wall of the second mounting tube 21; the top of the second mounting tube 21 is connected to the bottom of the second spring 22 through the second mounting ring 23. The second spring 22 is connected to the top of the water pump pipe 13; the top of the second mounting ring 23 is provided with two first push blocks 24, and the top of the first push block 24 is provided with a first chamfer 25, which faces the side wall of the water pump pipe 13; the output end of the first motor 26 is connected to one end of the first rotating shaft 27, and the first rotating shaft 27 passes through the side wall of the water pump pipe 13 and is connected to the first helical gear 28; the first helical gear 28 is meshed with the second helical gear 29, and each end of the second helical gear 29 is connected to a screw 30; each threaded part of the screw 30 is connected to a screw tube 31, the screw tube 31 is slidably connected to the water pump pipe 13, and the end of the screw tube 31 outside the water pump pipe 13 is connected to a second push block 32; the second chamfer at the bottom of the second push block 32 is in frictional engagement with the first chamfer 25.

[0022] like Figure 10-12 As shown, the drive assembly includes: a gear ring 33 mounted on the outer wall of the first mounting pipe 20, and a second motor 39 mounted on the outer wall of the pumping pipe 13, the second motor 39 being disposed opposite to the gear ring 33; the gear ring 33 meshes with a gear 34, the top of the gear 34 being rotatably connected to a first fixing rod fixed on the outer wall of the pumping pipe 13 via a second rotating shaft 35; the second rotating shaft 35 passes through the top of the first fixing rod and connects to a first crown tooth 36, the first crown tooth 36 meshing with a first cylindrical tooth 37, the first cylindrical tooth 37 passing through the side wall of the pumping pipe 13 via a third rotating shaft 38 and connecting to the output end of the second motor 39; the third rotating shaft 38, placed inside the pumping pipe 13, is provided with a second cylindrical tooth 40, the second cylindrical tooth 40 meshing with a second crown tooth 41; the bottom of the second crown tooth 41 is connected to the top of a fourth rotating shaft 42, the fourth rotating shaft 42 being rotatably connected to a second fixing rod fixed on the inner wall of the pumping pipe 13, and the bottom of the fourth rotating shaft 42 being connected to a blade 43.

[0023] like Figure 13 , 14As shown, the cleaning assembly includes: multiple push rods 44, the top of which is connected to the top of the outer wall of the second mounting pipe 21; the bottom of which is connected to the top of the output pipe 45; the bottom opening of the output pipe 45 is set towards the second filter hole 16; the outer wall of the output pipe 45 is slidably connected to the longitudinal pipe 46; the side wall of the longitudinal pipe 46 is connected to the inner wall of the annular pipe 48 through the pipe 47; the output pipe 45 is provided with a waist-shaped hole 49 on the side near the annular pipe 48; the waist-shaped hole 49 is set above the top wall of the pipe 47; the end of the water inlet pipe 50 is connected to the side wall of the annular pipe 48; the water inlet pipe 50 is connected to a pressure relief valve and a water pump; the other end of the water inlet pipe 50 is placed on the ground and connected to a water storage tank.

[0024] like Figure 1-15 As shown, the remediation method of the membrane contact electrocatalytic oxidation in-situ soil and groundwater remediation device includes: Step S1: Install multiple underground well pipes 1 within the repair area 4.

[0025] Step S2: Wrap a membrane cathode 11 around the first through hole 9 of the PU gas pipe 7 and surround a conductive anode 12 around the second through hole 10 of the electrode pipe 6, and install the electrode pipe 6, PU gas pipe 7 and aeration needle 8 inside the underground well pipe 1.

[0026] In this embodiment, before supplying raw gas to the underground well pipe 1, the end of a hose with a blower is connected to the top of the aeration needle 8. Then, the other end of the hose is connected to the raw gas storage tank. Subsequently, a sealing plate is used to seal the underground well pipe 1 and the hose. The inner wall of the hose is coated with chlorosulfonated polyethylene (CSM) coating. When the raw gas supplied by the hose contains O3, the chlorosulfonated polyethylene can prevent the inside of the hose from being corroded, thereby preventing damage after the device has been used for a period of time, thus preventing the leakage of raw gas, and at the same time preventing ozone from harming nearby personnel.

[0027] Step S3: The raw gas is delivered to the underground well pipe 1 through the gas supply pipe.

[0028] In this embodiment, the original gas is O2, or O3, or a mixture of O2 and O3. Specifically, when the original gas is transported, the original gas is O2, or O3, or a mixture of O2 and O3. When the organic matter content in the wastewater of the remediation zone 4 is high, O2 can be used directly as the original gas. When the organic matter content in the remediation zone 4 is high, O3 gas can be directly introduced. It is used to carry out an electrocatalytic reaction in the underground well pipe 1 to generate free radicals. Its strong oxidizing properties are used to assist in oxidizing the residual organic matter, thereby improving the degree of wastewater treatment. Alternatively, a mixture of O2 and O3 gas can be introduced. After H2O2 liquid and free radicals are generated in the underground well pipe 1, the two work together to oxidize the organic matter, thereby increasing the oxidation rate.

[0029] Step S4: After supplying raw gas to the underground well pipe 1, connect the conductive anode 12 and the membrane cathode 11 in the underground well pipe 1 to the positive and negative terminals of the power supply, respectively.

[0030] Specifically, after the conductive anode 12 and the membrane cathode 11 are energized, the O2 in the mixed gas is reduced to liquid H2O2 at the membrane cathode 11. Under the catalysis of O3, it is converted into free radicals, and then the oxides in the wastewater can efficiently oxidize organic matter under the action of H2O2 and free radicals.

[0031] Step S5: Catalyze the original gas using the potential difference formed between the conductive anode 12 and the membrane cathode 11.

[0032] Step S6: After catalysis, H2O2 liquid is obtained. The H2O2 liquid enters the remediation zone 4 through the underground well pipe 1 to oxidize the organic matter in the sewage in the remediation zone 4. The sewage is groundwater contaminated by organic pollutants in the soil of the remediation zone 4.

[0033] Step S7: After the sewage is treated in the underground well pipe 1, multiple pumping wells 2 and injection wells 3 are set in the repair area 4. Sewage treatment components are installed in the pumping wells 2 and connected to the injection wells 3.

[0034] Specifically, each pumping well 2 is symmetrically arranged on both sides of an injection well 3. After the underground well pipe 1 finishes treating the sewage, some organic matter will still remain in the groundwater. At this time, the pumping well 2 pumps out the treated sewage near the underground well pipe 1 and re-injects it upstream of the underground well pipe 1 through the injection well 3. Through the flow of water, the oxidant discharged from the underground well pipe 1 is used again to uniformly treat the remaining organic matter, thereby improving the efficiency of sewage treatment.

[0035] In step S8, the residual organic matter is uniformly treated by reusing the oxidant discharged from the underground well pipe 1 through the sewage treatment component.

[0036] Specifically, water in pumping well 2 can re-enter injection well 3 through the first filter hole 14 on pumping pipe 13. The purpose is to allow groundwater to flow through underground pipe 1 again, and to oxidize the residual sewage through the H2O2 liquid in underground pipe 1, thereby improving the system's groundwater remediation effect. When pumping groundwater, impurities will still exist in pumping well 2 and there is a risk of clogging the first filter hole 14. Therefore, a sleeve 15 is installed on pumping pipe 13, and a second filter hole 16 is opened on the sleeve 15. The groundwater is initially filtered through the second filter hole 16. When the filtration capacity of the second filter hole 16 reaches its limit, the vibration component is activated and drives the sleeve 15 to reciprocate on pumping pipe 13 to vibrate and clean the impurities in the second filter hole 16. At the same time, the movement of the second filter hole 16 is used to crush the impurities stuck in the first filter hole 14, thereby maintaining the pumping capacity of pumping pipe 13. When the sleeve 15 is vibrated, the first mounting tube 20 drives the second oblique crown tooth 19 to rotate on the second mounting tube 21. Therefore, the oblique surface of the upper tooth of the second oblique crown tooth 19 can be frictionally engaged with the oblique surface of the upper tooth of the first oblique crown tooth 18, and thus the sleeve 15 can be vibrated under the elastic force of the first spring 51. If there are no impurities in the second filter hole 16, the sleeve 15 does not need to vibrate. However, when there are many impurities in the second filter hole 16, the water pressure in the pumping pipe 13 drops significantly. Therefore, it is necessary to increase the vibration amplitude of the sleeve 15. At this time, the first motor 26 starts, and its output end drives the first rotating shaft 27 to rotate. The first rotating shaft 27 drives the first helical gear 28 to rotate. The first helical gear 28 drives the second helical gear 29, which meshes with it, to rotate. The screw 30 rotates, which causes the screw tube 31, which is threadedly connected to its threaded part, to move to the outside of the pumping pipe 13. The screw tube 31 drives the second push block 32 to move. The second chamfer on the second push block 32 and the first chamfer 25 on the first push block 24 are in frictional engagement, which increases the downward movement distance of the second mounting tube 21 and the second mounting ring 23. The length of the second spring 22 becomes longer, and the bottom of the upper tooth of the second helical crown tooth 19 moves further toward the first helical crown tooth 18. Therefore, when the drive mechanism on the side wall of the first mounting tube 20 is started, the vibration amplitude of the sleeve 15 increases. When there are fewer impurities on the second filter hole 16, the water pressure in the pumping pipe 13 decreases less. The change in water pressure can be measured based on the pressure gauge in the existing technology. Therefore, it is necessary to increase the vibration amplitude of the sleeve 15. At this time, the first motor 26 starts, and its output end drives the first rotating shaft 27 to rotate in the opposite direction. The first rotating shaft 27 drives the first helical gear 28 to rotate in the opposite direction. The first helical gear 28 drives the second helical gear 29, which meshes with it, to rotate in the opposite direction. Finally, the screw 30 rotates in the opposite direction, thereby causing the screw tube 31, which is threadedly connected to its threaded part, to move into the pumping pipe 13. The screw tube 31 drives the second push block 32 to move. The second chamfer on the second push block 32 and the first chamfer 25 on the first push block 24 rub against each other again, reducing the downward movement distance of the second mounting tube 21 and the second mounting ring 23. The length of the second spring 22 becomes shorter, and the movement distance of the bottom of the upper tooth of the second helical crown tooth 19 towards the first helical crown tooth 18 decreases. Therefore, when the drive component on the side wall of the first mounting tube 20 is started, the vibration amplitude of the sleeve 15 decreases. The amplitude of the sleeve 15 can be adjusted according to the actual situation, which can avoid the phenomenon of incomplete cleaning when the second filter hole 16 is blocked and needs to be cleaned. At the same time, when the degree of blockage of the second filter hole 16 is not high, the vibration amplitude of the sleeve 15 is reduced, which can avoid the premature aging of the internal components of the mechanism due to excessive friction between the second oblique crown tooth 19 and the first oblique crown tooth 18, and extend the service life of the device.

[0037] When the first mounting tube 20 needs to be rotated, the second motor 39 starts and drives the third rotating shaft 38 to rotate. The first cylindrical tooth 37 and the second cylindrical tooth 40 on the third rotating shaft 38 rotate synchronously. The meshing connection between the first cylindrical tooth 37 and the first crown tooth 36 drives the second rotating shaft 35 and the gear 34 to rotate. In turn, the gear 34 drives the gear ring 33 that meshes with it to rotate. Since the height of the first mounting tube 20 can be adjusted, the thickness of the gear 34 is set to be greater than the thickness of the gear ring 33, and the bottom of the gear 34 is placed below the bottom of the gear ring 33. This prevents the mechanism from failing to drive the first mounting tube 20 to rotate after the height of the first mounting tube 20 is adjusted, thus improving the stability of the device during operation. While the third rotating shaft 38 rotates, the second cylindrical tooth 40 meshes with the second crown tooth 41. The second crown tooth 41 drives the blade 43 to rotate through the fourth rotating shaft 42, thereby reducing the water pressure in the pumping pipe 13 so that groundwater can be drawn from the second filter hole 16 into the pumping pipe 13. The mechanism optimizes the setting of the drive components in the device and reduces the complexity of the device.

[0038] While the second filter hole 16 is being cleaned by vibration, an output pipe 45 is installed in the device to clean the second filter hole 16 in order to increase the cleaning effect. When the cleaning starts, the water pump connected to the water inlet pipe 50 can draw water from the water storage tank into the annular pipe 48, and input it into the longitudinal pipe 46 through the pipe 47. Since the second installation pipe 21 moves downward at this time, the second installation pipe 21 drives the push rod 44 to move downward synchronously. The push rod 44 drives the output pipe 45 to move downward, and then the pipe 47 is connected to the waist-shaped hole 49. Water will be output through the output pipe 45 to the surface of the second filter hole 16 to assist in cleaning impurities, thereby improving the cleaning effect of impurities. If the vibration amplitude of the sleeve 15 is large, the conduction area of ​​the waist-shaped hole 49 is large, and the water output of the output pipe 45 is greater. If the vibration amplitude of the sleeve 15 is small, the conduction area of ​​the waist-shaped hole 49 is small, and the water output of the output pipe 45 is smaller. This not only avoids the water in the output pipe 45 from failing to effectively flush the impurities in the second filter hole 16, but also avoids the waste of water resources.

[0039] Step S9: After a period of sewage treatment, multiple monitoring wells 5 are set up in the remediation area 4. Groundwater is extracted from the remediation area 4 through the monitoring wells 5 and tested by the machine until the remediation is completed.

[0040] Specifically, after a period of sewage treatment, it is necessary to monitor the progress of sewage treatment. Groundwater can be extracted from the remediation area 4 through monitoring well 5 and tested on the machine to accurately determine in real time whether the oxides have been completely oxidized, so as to reduce the waste of oxidant. Meanwhile, when it is necessary to increase the efficiency of sewage treatment, monitoring well 5 can be used as a substitute for pumping well 2 and injection well 3 to assist in the circulation of groundwater near underground well pipe 1, thereby avoiding dead zones of organic matter oxidation during sewage treatment.

[0041] Finally, it should be noted that the above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A membrane contact electrocatalytic oxidation in-situ soil and groundwater remediation device, characterized in that, include: Multiple underground well pipes (1) for gas transport and catalytic reaction are set in the remediation area (4); Multiple pumping wells (2) are set up in the remediation area (4) for extracting groundwater contaminated by organic pollutants in the soil. The injection well (3) is used to reinject the treated clean water into the aquifer; and Multiple monitoring wells (5) are set up in the remediation area (4) for testing water samples after sewage treatment to assess the remediation effect and water quality changes. in, The underground well pipe (1) is provided with an electrode pipe (6) for fixing the anode structure. The electrode pipe (6) is provided with a PU gas pipe (7) for transporting the original gas to the catalytic reaction zone. The PU gas pipe (7) is provided with an aeration needle (8) for breaking the transported gas into microbubbles and increasing the gas-liquid contact area. The PU gas pipe (7) has multiple first through holes (9) on its side wall. The first through hole (9) near the electrode pipe (6) is wrapped with a membrane cathode (11) for reducing the transported gas into H2O2 liquid. The electrode tube (6) has a plurality of second through holes (10) on its sidewall. The second through holes (10) are surrounded by a conductive anode (12) on the side of the PU gas tube (7) for generating active hydroxyl radicals to directly oxidize organic matter after being energized. The membrane cathode (11) and the conductive anode (12) work together to oxidize and degrade pollutants. The pumping well (2) is equipped with a sewage treatment component, and the output end of the sewage treatment component is placed in the injection well (3). The three adjacent underground well pipes (1) are arranged in an equilateral triangle, and each pumping well (2) is symmetrically arranged on both sides of an injection well (3).

2. The membrane contact electrocatalytic oxidation in-situ soil and groundwater remediation device according to claim 1, characterized in that, The underground well pipe (1) is a PVC pipe with a 200-mesh high-density nylon screen.

3. The membrane contact electrocatalytic oxidation in-situ soil and groundwater remediation device according to claim 1, characterized in that, The wastewater treatment component includes: a pumping pipe (13). The input end of the pumping pipe (13) with multiple first filter holes (14) is placed inside the pumping well (2), and the output end of the pumping pipe (13) is placed inside the injection well (3). The pumping pipe (13) has a sleeve (15) that is slidably sealed to the outside of the first filter hole (14), and the sleeve (15) has a plurality of second filter holes (16). The bottom of the outer wall of the pumping pipe (13) is connected to the protective pipe (17) through the first mounting ring. The protective pipe (17) is provided with a first spring (51). The bottom of the first spring (51) is connected to the first mounting ring, and the top of the spring (51) is connected to the bottom of the sleeve (15). The sleeve (15) and the protective pipe (17) are slidably connected. The top of the sleeve (15) is provided with a first oblique crown tooth (18), which is connected to the vibration assembly.

4. The membrane contact electrocatalytic oxidation in-situ soil and groundwater remediation device according to claim 3, characterized in that, The vibration assembly includes: a second oblique crown tooth (19) and a first motor (26) disposed on the outer wall of the pumping pipe (13); The bottom of the second oblique crown tooth (19) is located below the top of the first oblique crown tooth (18), and the oblique surface of the second oblique crown tooth (19) slides in engagement with the oblique surface of the first oblique crown tooth (18); The top of the second oblique crown tooth (19) is connected to the bottom of the first mounting tube (20); The top inner wall of the first mounting tube (20) is rotatably connected to the outer wall of the second mounting tube (21), and a drive assembly is provided on the outer wall of the first mounting tube (20). The inner wall of the second mounting pipe (21) is slidably connected to the outer wall of the pumping pipe (13), and a cleaning component is provided on the top of the outer wall of the second mounting pipe (21). The top of the second mounting tube (21) is connected to the bottom of the second spring (22) via the second mounting ring (23); The top of the second spring (22) is connected to the water pump pipe (13); The second mounting ring (23) is provided with two first push blocks (24) at the top. The first push block (24) is provided with a first chamfer (25) at the top. The first chamfer (25) is provided facing the side wall of the water pipe (13). The output end of the first motor (26) is connected to one end of the first rotating shaft (27), and the first rotating shaft (27) passes through the side wall of the water pumping pipe (13) and is connected to the first helical gear (28). The first helical gear (28) meshes with the second helical gear (29), and each end of the second helical gear (29) is connected to a screw (30). Each threaded portion of the screw (30) is connected to a threaded tube (31), the threaded tube (31) is slidably connected to the water pumping pipe (13), and the end of the threaded tube (31) outside the water pumping pipe (13) is connected to a second push block (32). The second chamfer at the bottom of the second push block (32) is in frictional engagement with the first chamfer (25).

5. The membrane contact electrocatalytic oxidation in-situ soil and groundwater remediation device according to claim 4, characterized in that, The drive assembly includes: a toothed ring (33) mounted on the outer side wall of the first mounting pipe (20), and a second motor (39) mounted on the outer side wall of the pumping pipe (13), the second motor (39) being disposed opposite to the toothed ring (33); The gear ring (33) meshes with the gear (34), and the top of the gear (34) is rotatably connected to the first fixing rod fixed on the outer wall of the pumping pipe (13) via the second rotating shaft (35). The second rotating shaft (35) passes through the top of the first fixed rod and connects to the first crown tooth (36). The first crown tooth (36) meshes with the first cylindrical tooth (37). The first cylindrical tooth (37) passes through the side wall of the water pumping pipe (13) via the third rotating shaft (38) and connects to the output end of the second motor (39). The third rotating shaft (38) placed inside the water pumping pipe (13) is provided with a second cylindrical tooth (40), which meshes with the second crown tooth (41). The bottom of the second crown tooth (41) is connected to the top of the fourth rotating shaft (42), which is rotatably connected to the second fixing rod fixed to the inner side wall of the pumping pipe (13), and the bottom of the fourth rotating shaft (42) is connected to the blade (43).

6. The membrane contact electrocatalytic oxidation in-situ soil and groundwater remediation device according to claim 4, characterized in that, The cleaning assembly includes: multiple push rods (44). The top of the push rod (44) is connected to the top of the outer wall of the second mounting tube (21); The bottom of the push rod (44) is connected to the top of the output tube (45); The bottom opening of the output tube (45) is set towards the second filter hole (16), the outer wall of the output tube (45) is slidably connected to the longitudinal tube (46), and the side wall of the longitudinal tube (46) is connected to the inner wall of the annular tube (48) through the pipe (47). The output pipe (45) has a waist-shaped hole (49) on the side near the annular pipe (48), and the waist-shaped hole (49) is located above the top wall of the pipe (47); The end of the water inlet pipe (50) is connected to the side wall of the annular pipe (48). The water inlet pipe (50) is connected to a pressure relief valve and a water pump. The other end of the water inlet pipe (50) is placed on the ground and connected to a water storage tank.

7. A remediation method based on the membrane contact electrocatalytic oxidation in-situ soil and groundwater remediation device according to any one of claims 1-6, characterized in that, include: Step S1: Install multiple underground well pipes (1) in the repair area (4); Step S2: Wrap the membrane cathode (11) at the first through hole (9) of the PU gas pipe (7), and surround the conductive anode (12) at the second through hole (10) of the electrode pipe (6), and install the electrode pipe (6), PU gas pipe (7), and aeration needle (8) inside the underground well pipe (1); Step S3: Supply raw gas to the underground well pipe (1) through the gas supply pipe; Step S4: After supplying the raw gas to the underground well pipe (1), connect the conductive anode (12) and the membrane cathode (11) in the underground well pipe (1) to the positive and negative terminals of the power supply, respectively. Step S5: Catalyze the original gas using the potential difference formed between the conductive anode (12) and the membrane cathode (11); Step S6: After catalysis, H2O2 liquid is obtained. The H2O2 liquid enters the remediation zone (4) through the underground well pipe (1) to oxidize the organic matter in the sewage in the remediation zone (4). The sewage is groundwater polluted by organic pollutants in the soil of the remediation zone (4). Step S7: After the sewage is treated by the underground well pipe (1), a plurality of pumping wells (2) and injection wells (3) are set in the repair area (4). The sewage treatment components are installed in the pumping wells (2) and connected to the injection wells (3). Step S8: The residual organic matter is uniformly treated again by the oxidant discharged from the underground well pipe (1) through the sewage treatment component; Step S9: After a period of sewage treatment, multiple monitoring wells (5) are set up in the remediation area (4). Groundwater is extracted from the remediation area (4) through the monitoring wells (5) and tested on the machine until the remediation is completed.

8. The repair method according to claim 7, characterized in that, In step S2, before supplying raw gas to the underground well pipe (1), the end of the hose with the air pump is connected to the top of the aeration needle (8), and then the other end of the hose is connected to the raw gas storage tank. Then, a sealing plate is used to seal the underground well pipe (1) and the hose.

9. The repair method according to claim 7, characterized in that, In step S3, the original gas is O2, or O3, or a mixture of O2 and O3.

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