A cycled well system for removing volatile organic contaminants from soil and groundwater

Abstract

The application discloses a circulating well system for removing volatile organic pollutants in soil and underground water, which comprises a circulating well and a plurality of in-situ resistance heating wells; the circulating well is provided with a screen pipe at a position corresponding to an underground water-bearing layer, and a barrier is arranged in the circulating well for separating upper and lower water-bearing layers; a water pumping pump is arranged in the screen pipe of the upper water-bearing layer, and a water injection pump is arranged in the screen pipe of the lower water-bearing layer; the water pumping pump is connected with an inlet of a steam-water separator; the steam-water separator is connected with a waste gas treatment system and a waste water treatment system; the waste water treatment system is connected with the water injection pump; and the plurality of in-situ resistance heating wells are arranged around the circulating well and used for heating contaminated soil and underground water. The application promotes the volatilization and escape of volatile organic pollutants in soil and underground water through resistance heating enhancement, removes the pollutants after pumping out the contaminated underground water through the circulating well system, and then forms a circulation treatment by injecting clean water, so that the volatile organic pollutants in soil and underground water are effectively repaired.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of soil and groundwater organic pollution remediation technology, in particular to a circulating well system for removing volatile organic pollutants in soil and groundwater. BACKGROUND

[0002] The groundwater circulating well technology is an in-situ remediation technology, which accelerates the vertical circulation of groundwater by pumping and injecting groundwater at different depths of the aquifer, overcomes the vertical heterogeneity of the stratum, collects the pollutants in the circulating well body within a large influence radius, removes the pollutants by pumping to the ground water treatment system or the well body treatment system, and gradually reduces the pollutant concentration until the remediation meets the standard. The circulating well technology is a very advantageous remediation technology for sites with medium to high permeability, and the influence radius of the circulating well technology in sand layer can exceed 45m. It has obvious advantages in treating sites with large pollution range and deep vertical pollution depth, and has been widely used abroad. At present, there are also relevant engineering implementation cases in China.

[0003] The existing groundwater circulating well mainly relies on the horizontal trapping force and the vertical scouring force of the circulating well to remove the pollutants in the soil and groundwater. The removal effect is not ideal for pollutants with strong adsorption in the soil and pollutants with cross solubility. Based on the defect, the enhanced circulating well system is proposed. The enhanced circulating well system utilizes the electrically conductive characteristics of groundwater itself, and on the basis of the traditional circulating well technology, the soil and groundwater are heated in a large range by coupling the in-situ resistance heating technology. On the one hand, the in-situ resistance heating technology promotes the dissolution of the pollutants in the soil into the groundwater, and enhances the removal capacity of the pollutants. On the other hand, the in-situ resistance heating technology promotes the faster conversion of the pumped pollutants into gas phase and liquid phase, and cooperatively enhances the efficiency of the circulating well in capturing the pollutants. Through the enhanced circulating well system, the application range of the circulating well can be widened, and the enhanced circulating well system is applicable to strata with low permeability, pollutants with strong adsorption in the soil, and pollutants with cross solubility. SUMMARY

[0004] In view of the deficiencies in the prior art, the present application provides a circulating well system for removing volatile organic pollutants in soil and groundwater, which belongs to an enhanced circulating well system.

[0005] The present application discloses a circulating well system for removing volatile organic pollutants in soil and groundwater, which comprises a circulating well and a plurality of in-situ resistance heating wells.

[0006] The circulating well comprises screen pipes corresponding to different depth positions of underground water aquifers and real pipes connecting adjacent two screen pipe sections, a barrier is arranged in the circulating well for separating upper and lower aquifers, a water pumping pump is arranged in the upper aquifer screen pipe, a water injection pump is arranged in the lower aquifer screen pipe, a water outlet of the water pumping pump is connected with an inlet of a steam-water separator through an underground water pumping pipe, a gas outlet of the steam-water separator is connected with a waste gas treatment system, a water outlet of the waste gas treatment system is connected with a water inlet of the water injection pump;

[0007] A plurality of the in-situ resistance heating wells are arranged around the circulating well for heating the contaminated soil and underground water.

[0008] As a further improvement of the present application, the in-situ resistance heating well uses underground water as a conductor, heats the soil and underground water in the contaminated remediation area through electric current, changes the occurrence form of the pollutants in the ground by increasing the temperature of the contaminated area, increases the concentration of the pollutants in the gas phase or liquid phase, promotes the dissolution and escape of the volatile organic pollutants, and enhances the collection and removal of the pollutants by the circulating well.

[0009] As a further improvement of the present application, the in-situ resistance heating well is provided with a heating electrode and a conductive material, the heating electrode is connected with a power supply adjusting system capable of adjusting the power supply current, a plurality of the in-situ resistance heating wells are arranged around the circulating well according to the point hexagon full coverage principle, and further, the distribution of the in-situ resistance heating well is determined according to the influence radius, the heating influence radius can be determined through field test and other means before large-scale implementation, and the appropriate in-situ resistance heating well setting position and power supply input are selected by fully considering the remediation period, construction cost and safety requirements.

[0010] As a further improvement of the present application, the temperature measuring system is further provided.

[0011] The temperature measuring system comprises a plurality of vertical underground temperature measuring pipes and underground water temperature measuring instruments arranged at intervals on the underground temperature measuring pipes.

[0012] The underground water temperature measuring instruments are connected with the power supply adjusting system, the power supply adjusting system adjusts the current of the heating electrode based on the temperature monitored by the underground water temperature measuring instruments, so that the heating temperature of the in-situ resistance heating well is controlled at 50-100 DEG C, and the organic pollutants in the soil and underground water are heated and removed in stages; in the process of heating and temperature rising, the pollutants dissolved in the underground water are removed by the circulating well through pumping out the underground water in the early stage of temperature rising, with the continuous increase of the underground temperature, the volatile organic pollutants adsorbed in the underground soil and the pollutants with high boiling point dissolved in the underground water tend to be more efficiently dissolved in the pumped out underground water, so that the pollution remediation range is expanded and the efficiency of removing the pollutants is improved.

[0013] As a further improvement of the present application, the arrangement principle of all the groundwater temperature measuring instruments is: covering all the heating areas, being arranged in the cold point position of the heating electrode distribution in a plane and being uniformly distributed in each stratum; if there is only one stratum in the whole aquifer, being uniformly distributed in the whole aquifer.

[0014] As a further improvement of the present application, the extracted groundwater and volatile gas are separated by a steam-water separator and enter a waste water treatment system and a waste gas treatment system respectively, the treated water is re-injected into the circulating well after the extracted groundwater is treated, if the temperature of the treated water has a large floating change, the waste water treatment system is equipped with a heating system to ensure that the temperature of the injected water is not lower than that of the extracted water. Further, the temperature measuring system further comprises an extracted groundwater temperature measuring instrument arranged on the groundwater extraction pipe and an injected water temperature measuring instrument arranged on the groundwater injection pipe, the waste water treatment system is provided with a heating assembly, the extracted groundwater temperature measuring instrument and the injected water temperature measuring instrument are connected with the input end of the heating control unit, and the output end of the heating control unit is connected with the heating assembly. When the heating control unit detects that the temperature of the injected water is lower than that of the extracted water, the heating assembly is controlled to work to ensure that the temperature of the injected water is not lower than that of the extracted water.

[0015] As a further improvement of the present application, it further comprises a fixed rod.

[0016] The fixed rod is provided with a water level meter corresponding to different depth positions of the groundwater aquifer, and the water level meter is linked with the water pump and the water injection pump.

[0017] As a further improvement of the present application, the barrier is an air inflation type barrier, which is used for blocking the space in the well between the upper and lower screen pipes and respectively performing extraction and injection. The extracted groundwater enters a steam-water separation device to separate the gaseous pollutants and the pollutants dissolved in the water, and then the waste water treatment and waste gas treatment are respectively performed. The barrier is connected with an above-ground control device, the position of the barrier in the circulating well is adjusted based on the above-ground control device, so that the space volume of the circulating well body for injecting clean water and extracting contaminated water is different. According to the extraction amount and injection amount of the contaminated groundwater or the difficulty of extraction / injection, the water pressure in the circulating well body can be indirectly adjusted by adjusting the position of the barrier, so as to affect the influence range of extraction and injection.

[0018] As a further improvement of the present application, the waste water treatment system is an oxidation water treatment system or a reduction water treatment system, the extracted contaminated groundwater is re-injected into the underground circulating well after water treatment to participate in the next stage of circulation. In order to improve the removal efficiency of pollutants, the waste water treatment system is equipped with a heating assembly to ensure that the temperature of the injected water is not lower than that of the extracted water.

[0019] As a further improvement of the present application, the waste gas treatment system is an activated carbon adsorption system or a catalytic combustion system, and can also be directly combusted, and finally reaches the emission standard.

[0020] As a further improvement of the present application, the maximum extraction and injection flow of the circulation well system is not more than 30 m 3 / h, the treatment capacity of the waste water treatment system is not less than 35 m 3 / h, and the operation capacity of the waste gas treatment system is not less than 30 m 3 / h, two-stage 15 m 3 / h equipment can be used in parallel, and in the initial heating and heating period and the later treatment operation period, 15 m 3 / h treatment capacity can only start any one-stage system.

[0021] As a further improvement of the present application, the main structure material of the circulation well is 304 or 316L stainless steel, and the screen gap gap of the well body screen pipe part is 1-2 mm; the pipe components such as the water pumping pipe, the water injection pipe and the elbow are all made of stainless steel.

[0022] As a further improvement of the present application, the main well diameter of the circulation well is 30-40 cm, and the upper and lower well body connection mode can be a spiral form or a buckle form.

[0023] As a further improvement of the present application, the water pumping pump and the water injection pump in the circulation well are made of stainless steel.

[0024] As a further improvement of the present application, the heating system comprises a transformer, a power control unit, an electrode well and a control cabinet, the control cabinet is connected with the electrode well, and the electrode is made of galvanized steel.

[0025] Compared with the prior art, the present application has the following beneficial effects:

[0026] The present application utilizes the conductive characteristics of the underground water itself, and on the basis of the traditional circulation well technology, the soil and underground water are heated in a large range through coupling in-situ resistance heating technology, which promotes the dissolution of the pollutants in the soil into the underground water, and promotes the extraction of the pollutants into gas phase and liquid phase, thereby synergistically enhancing the efficiency of the circulation well in capturing the pollutants.

[0027] The present application installs a steam-water separator outside the circulation well, and the polluted underground water extracted is subjected to steam-water separation, so that the gas phase and the liquid phase enter the waste gas treatment system and the waste water treatment system respectively, thereby specifically enhancing the treatment efficiency of the pollutants and improving the recirculation well injection capacity after the treatment of the polluted underground water.

[0028] The present application adopts wide-range heating to control the phase change of volatile organic pollutants in underground soil and groundwater at different temperature sections, and to enhance the volatilization of pollutants with different boiling points in sequence, and then removes the pollutants by cooperating with above-ground disposal facilities. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 Layout plan of the circulating well system for removing volatile organic pollutants in soil and groundwater disclosed by the present application;

[0030] Figure 2 Sectional view of the circulating well system for removing volatile organic pollutants in soil and groundwater disclosed by the present application.

[0031] In the drawings:

[0032] 1, circulating well; 2, in-situ resistance heating well; 3, steam-water separator; 4, wastewater treatment system; 5, waste gas treatment system; 6, groundwater extraction pipe; 7, groundwater injection pipe; 8, injection water temperature measuring instrument; 9, extracted groundwater temperature measuring instrument; 10, barrier; 11, power supply adjustment system; 12, temperature measuring system; 13, underground temperature measuring pipe; 14, water injection pump; 15, water extraction pump; 16, upper aquifer screen pipe; 17, solid pipe; 18, lower aquifer screen pipe; 19, fixed rod; 20, upper water level instrument; 21, lower water level instrument; 22, underground temperature measuring instrument. DETAILED DESCRIPTION

[0033] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0034] The application provides an enhanced circulation well system for removing volatile organic pollutants in soil and underground water, which comprises an in-situ resistance heating well system for electrically heating contaminated soil and underground water, a temperature measuring system for measuring the temperature of the underground and the ground, a circulation well system for pumping and injecting underground water to generate a vertical underground water flow field, and a matched wastewater treatment system and a waste gas treatment system; wherein the in-situ resistance heating well is distributed around the circulation well, the underground water is used as a conductor, the soil and the underground water in the contaminated remediation area are heated by electric current, the dissolution and escape of the volatile organic pollutants are promoted, and the collection and removal of the pollutants by the circulation well are enhanced; the working temperature of the in-situ resistance heating well is adjusted by the feedback of the underground temperature measuring point to the power supply adjustment system, the heating temperature is controlled in stages at 50-100 DEG C through temperature measurement, and the pollutants with different boiling points in the soil and the underground water are heated and removed in stages. The heated underground water is pumped to the ground through the circulation well, a steam-water separator is arranged in front of the wastewater treatment system, the pumped underground water and the volatile gas are separated through the steam-water separation device, and are respectively introduced into the wastewater treatment system and the waste gas treatment system, the pumped underground water is treated through the wastewater treatment system, and the treated water is re-injected into the circulation well; if the temperature after treatment has a large floating change, the wastewater treatment system is provided with a heating component, so that the temperature of the injected water is not lower than that of the pumped water. The application promotes the volatilization and escape of the volatile organic pollutants in the soil and the underground water through resistance heating enhancement, the contaminated underground water is pumped out through the circulation well system, the pollutants are removed, then clean water is injected to form a circulation treatment, and the volatile organic pollutants in the soil and the underground water are effectively remediated.

[0035] In the underground water and the soil, 1000m 2 The application is described below by taking a contaminated site as an example.

[0036] As shown in Figure 1 , 2 The application provides an enhanced circulation well system for removing volatile organic pollutants in soil and underground water, which comprises an in-situ resistance heating well system for electrically heating contaminated soil and underground water, a temperature measuring system for measuring the temperature of the underground and the ground, a circulation well system for pumping and injecting underground water to generate a vertical underground water flow field, and a matched wastewater treatment system and a waste gas treatment system; wherein,

[0037] The in-situ resistance heating well system of the application comprises a power supply adjusting system 11, an above-ground power supply line, and an in-situ resistance heating well 2 and an electrode unit arranged around the circulating well 1 and cooperating with the circulating well 1 to perform a remediation operation; the power supply adjusting system is composed of a transformer, a power control system, and a cable, and the in-situ resistance heating well is provided with heating electrodes and conductive materials; the influence radius of the in-situ heating well and the influence radius of the circulating well are determined through field pilot tests according to the project remediation site conditions, the influence radius a of the in-situ heating well is determined as 5 m, the influence radius b of the circulating well is 20 m, and then according to the principle of point six-hexagon full coverage, the arrangement of the in-situ heating well and the circulating well on site is as shown in Figure 1 Meanwhile, according to the planar layout of the in-situ electric heating system on site, the control of the electrode well can adopt independent control of each unit or unified control of similar units, the underground heating temperature rise condition is fed back through the temperature measurement system, the heating power of the electrode well is adjusted by adjusting the supply of voltage and current, so as to adjust the temperature around a single heating well or the underground temperature of a block.

[0038] The temperature measurement system 12 of the application comprises a plurality of vertical underground temperature measurement pipes 13, underground water temperature measuring instruments 22 arranged at intervals on the underground temperature measurement pipes, an extracted underground water temperature measuring instrument 9 arranged on the underground water extraction pipe 6, and an injected water temperature measuring instrument 8 arranged on the underground water injection pipe 7, and the underground temperature measurement pipe 13 can be placed in a temperature well; the temperature well for monitoring the heating temperature in the underground soil / underground water is a small-diameter stainless steel well with a closed structure, which serves to protect the underground water temperature measuring instrument 22 and place it at a suitable depth range, the underground water temperature measuring instrument 22 is a thermocouple temperature sensing element installed on the wall of the temperature well, and the temperature data is transmitted to an above-ground receiver for recording through a signal line. The extracted underground water temperature measuring instrument 9 and the injected water temperature measuring instrument 8 for monitoring the water temperature in the extraction pipeline and the injection pipeline of the circulating well are temperature measuring instruments installed on the outer wall of the pipeline, which are radially installed on the side wall of the pipeline by flanges or screws, and the temperature of the fluid in the pipeline is measured by the expansion degree of the metal sheet built-in the flow space in the pipeline at different temperatures. The feedback data of the underground temperature measuring instrument 22 is linked to the in-situ heating system by the temperature measurement system 12, the power input is adjusted through the coupling analysis feedback of the temperature data and the extracted contaminant treatment capacity, the constant temperature treatment is adopted for the contaminant with a large volatilization amount in a certain temperature range until the treatment efficiency is stably decreased and the temperature is increased again, the contaminant in a higher temperature range is heated to promote dissolution and volatilization, and then removed, so that the heating temperature of the in-situ resistance heating well is controlled at 50-100℃ through the temperature control and remediation operation cooperative treatment. The heating assembly is arranged in the wastewater treatment system 4, the extracted underground water temperature measuring instrument 9 and the injected water temperature measuring instrument 8 are connected to the input end of the heating control unit, the output end of the heating control unit is connected to the heating assembly, and when the heating control unit detects that the temperature of the injected water is lower than that of the extracted water, the heating assembly is controlled to work to ensure that the temperature of the injected water is not lower than that of the extracted water.

[0039] The circulating well 1 of this invention includes screen pipes corresponding to different depths of the groundwater aquifer and solid pipes connecting adjacent screen pipe sections, such as... Figure 2 The upper aquifer screen pipe 16, solid pipe 17, and lower aquifer screen pipe 18 shown are generally made of stainless steel. According to project requirements, the diameter of the well is 35cm. The well is constructed using a long spiral drilling rig. The well contains a groundwater injection pipe 7 and a water injection pump 14 for aquifer injection, a groundwater extraction pipe 6 and a water pump 15 for aquifer extraction, a barrier 10 and its adjustment device for isolating different aquifers in the well, and a vapor-water separator 3 for separating groundwater from volatile gases. After vapor-water separation, the polluted water enters the wastewater treatment system 4, and the waste gas enters the surface waste gas treatment system 5. According to the nature of volatile organic pollutants, the main treatment process of the surface wastewater treatment system 4 is oxidation, and the main treatment process of the waste gas treatment system 5 adopts flexible on-site treatment methods such as activated carbon adsorption. The well is equipped with an upper water level gauge 20 and a lower water level gauge 21. Two or more water level gauges are placed in different aquifers via stainless steel fixing rods 19. The water level gauges monitor the aquifer height within the well, regulating pumping and injection operations. The isolator 10 in the circulating well separates the upper and lower aquifers within the well body. The isolator expands by inflating to create a vertical separation within the well body, but the lower pumping pipes, pump lines, and monitoring instruments still function by passing through the isolator body. Multiple isolators 10 can be installed within the circulating well as needed, moving up and down according to the depth of the target aquifer. As described above, both the pipes pumping out contaminated water and injecting clean water are equipped with thermometers to measure the water temperature at both locations, reflecting the underground heating situation and ensuring that the injected clean water does not lower the overall underground temperature. If the clean water temperature drops significantly after the wastewater treatment process, a heating rod is installed in the clean water tank to heat the water to at least the outlet temperature. The extraction and injection rate of each well in the circulating well system is 15m. 3 / h, the surface water treatment system has a treatment capacity of 20m³. 3 / h, after gas-liquid separation, the exhaust gas enters the exhaust gas treatment system, undergoes condensation-adsorption, and is discharged after meeting standards. The condensed waste liquid enters the wastewater treatment system. The exhaust gas treatment system has an operating capacity of 20m³ / h. 3 / h.

[0040] The application utilizes the extraction and injection of different aquifers by the circulating well system to extract the contaminated groundwater and inject clean water, thereby forming a vertical groundwater flow field between different strata, and continuously removing the pollutants in the soil and groundwater by extraction, which has the advantages of large vertical and horizontal influence radius, and overcomes the problem that the pollutants in the heterogeneous stratum are difficult to migrate quickly, and through the enhanced heating of the in-situ heating well, the dissolution and release of the pollutants are promoted quickly, the release efficiency and removal efficiency of the pollutants are greatly enhanced, the complete extraction and removal of different boiling point volatile pollutants are ensured, and there is no rebound and secondary pollution risk of the pollutants in the later period.

[0041] The construction and repair method of the enhanced circulating well system of the application comprises the following steps:

[0042] S1, according to the project repair site conditions, the influence radius of the in-situ heating well and the influence radius of the circulating well are determined by field pilot test, the influence radius a of the in-situ heating well 2 is determined as 5 m, the influence radius b of the circulating well 1 is 20 m, and then according to the principle of point hexagonal full coverage, the layout of the in-situ heating well and the circulating well on site is as shown in Figure 1 .

[0043] S2, the circulating well system and the in-situ heating system are constructed: one circulating well is set, which is 10 m long and has a well diameter of 35 cm, since the circulating well pipe well diameter is large, long spiral drilling machine is needed for drilling, and the drilled drilling cuttings are collected and repaired and treated. The circulating well pipe installation needs to be installed gradually according to the pipe well section, a small crane is used to install the stainless steel circulating well and its internal pipeline, pump body, barrier and monitoring structure to the set depth, the screen pipe section between the pipe well and the soil wall is filled with quartz sand, and the real pipe section is filled with bentonite. The number of in-situ heating electrode wells is 115, and the depth is 10 m. The electrode wells are installed in the drilled holes by using a survey drilling machine, and the periphery is filled with quartz sand and iron-carbon which are supporting and conductive materials. The heating wells are connected by the ground distribution wires, and the voltage control switch is used to heat and adjust each heating well.

[0044] S3, the heating system temperature is set to 85-90 DEG C, and the heating starts before the circulating well is operated to heat the soil and groundwater in the covered area. During the heating from normal temperature to 60 DEG C, the pollutants are slowly dissolved, the concentration of the pollutants extracted and treated by the circulating well is low, and the removal amount is small; as the temperature rises, more pollutants are dissolved from the soil into the groundwater, and part of the pollutants are volatilized into gas phase, and the dissolved pollutants and the gas phase pollutants are repaired and treated by the steam-water separation device during the extraction process. During the heating process from 60 DEG C to 85 DEG C, the release efficiency and volatilization amount of the pollutants are the largest, and in the later heating stage, since most of the pollutants are removed, the extraction efficiency and extraction amount of the pollutants decrease, and the load of the treatment system for the end waste water and waste gas decreases.

[0045] S4, the contaminated groundwater pumped to the wastewater treatment system is oxidized and decomposed by chemical oxidation, and the clean water after treatment is recycled and injected into the well body in a suitable aquifer for vertical circulation; the waste gas containing pollutants pumped to the waste gas treatment system is removed by activated carbon adsorption and finally discharged up to standard.

[0046] Advantages of the present application:

[0047] The present application is aimed at the nature of volatile organic pollutants, utilizes the conductive characteristics of groundwater itself, and on the basis of traditional circulation well technology, through coupling in-situ resistance heating technology, heats the soil and groundwater in a large range, promotes the dissolution of pollutants in the soil into groundwater on the one hand, and promotes the extraction of pollutants into gas and liquid phases on the other hand, and synergistically enhances the efficiency of the circulation well in capturing pollutants;

[0048] The present application installs a steam-water separator in the circulation well body, separates the water vapor of the extracted contaminated groundwater, and makes the gas phase and the liquid phase enter the waste gas treatment system and the waste water treatment system respectively, thereby specifically enhancing the treatment efficiency of the pollutants and improving the recirculation injection capacity of the circulation well after treatment of the contaminated groundwater;

[0049] The present application uses large-scale heating to control the phase change of volatile organic pollutants in the soil and groundwater at different temperature ranges, and sequentially enhances the volatilization of pollutants with different boiling points, and cooperates with the aboveground disposal facilities to remove the pollutants.

[0050] The above is only a preferred embodiment of the present application and is not used to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A cycled well system for removing volatile organic contaminants from soil and groundwater, characterized in that, The application relates to a circulating well and a plurality of in-situ resistance heating wells. The circulating well comprises screen pipes corresponding to different depth positions of underground water aquifers and real pipes connecting adjacent two screen pipe sections, a baffle is arranged in the circulating well for separating upper and lower aquifers, a water pumping pump is arranged in the upper aquifer screen pipe, a water injection pump is arranged in the lower aquifer screen pipe, a water outlet of the water pumping pump is connected with an inlet of a steam-water separator through an underground water pumping pipe, a gas outlet of the steam-water separator is connected with a waste gas treatment system, a water outlet of the waste gas treatment system is connected with a water inlet of a waste water treatment system through an underground water injection pipe, and a water inlet of the water injection pump is connected with the water outlet of the waste water treatment system. The plurality of in-situ resistance heating wells are arranged around the circulating well and used for heating contaminated soil and underground water. The in-situ resistance heating well is provided with a heating electrode and conductive material, the heating electrode is connected with a power supply adjusting system capable of adjusting power supply current, and the plurality of in-situ resistance heating wells are arranged around the circulating well according to a point hexagon full coverage principle. The application further comprises a temperature measuring system. The temperature measuring system comprises a plurality of vertical underground temperature measuring pipes and underground water temperature measuring instruments arranged at intervals on the underground temperature measuring pipes. The underground water temperature measuring instruments are connected with the power supply adjusting system, the power supply adjusting system adjusts the current of the heating electrode based on the temperature monitored by the underground water temperature measuring instruments, and the heating temperature of the in-situ resistance heating well is controlled to be 50-100 DEG C. The application further comprises a fixing rod, water level meters are installed on the fixing rod at positions corresponding to different depth positions of underground water aquifers, and the water level meters are connected with the water pumping pump and the water injection pump. The arrangement principle of all the underground water temperature measuring instruments is that all heating areas are covered, the planar arrangement is located at cold point positions of the heating electrode distribution and is uniformly distributed in each stratum, and if there is only one stratum in the whole aquifer, the underground water temperature measuring instruments are uniformly distributed in the whole aquifer.

2. The circulation well system of claim 1, wherein, The temperature measuring system further comprises a pumped underground water temperature measuring instrument arranged on the underground water pumping pipe and an injected water temperature measuring instrument arranged on the underground water injection pipe, the waste water treatment system is provided with a heating assembly, the pumped underground water temperature measuring instrument and the injected water temperature measuring instrument are connected with an input end of a heating control unit, and an output end of the heating control unit is connected with the heating assembly, so that the temperature of the injected water is not lower than that of the pumped water.

3. The circulation well system of claim 1, wherein, The baffle is an air inflation type baffle, the baffle is connected with an aboveground control device, and the up-down position of the baffle in the circulating well is adjusted based on the aboveground control device.

4. The circulation well system of claim 1, wherein, The waste water treatment system is an oxidation water treatment system or a reduction water treatment system.

5. The circulation well system of claim 1, wherein, The waste gas treatment system is an activated carbon adsorption system or a catalytic combustion system.

6. The circulation well system of claim 1, wherein, ​ 7. The circulation well system of claim 1, wherein, The maximum flow of extraction and injection of the circulating well system is not more than 30 m 3 / h, the processing capacity of the wastewater treatment system is not less than 35 m 3 / h, the operation capacity of the exhaust gas treatment system is not less than 30 m 3 / h.

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