A multi-phase extraction and combined venting aeration based contaminated site treatment system

Abstract

The application discloses a contaminated site treatment system based on multi-phase extraction and combined ventilation aeration, which comprises a multi-phase extraction unit, a combined ventilation aeration unit, a tail gas treatment unit and a gas extraction circulation unit, the combined ventilation aeration unit is used for injecting gas into the aeration zone of the contaminated site, the combined ventilation aeration unit comprises a gas injection well and / or an aeration well, a gas injection pipe is arranged corresponding to the gas injection well and / or the aeration well, the input end of the gas injection pipe is connected with the output end of the gas extraction circulation unit through a locking device, and the contaminated site treatment system based on multi-phase extraction and combined ventilation aeration can efficiently complete the disassembly and assembly between the input end of the gas injection pipe and the output end of the gas extraction circulation unit, time and labor are saved, and the system is stable and reliable.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of contaminated soil treatment, and particularly relates to a contaminated site treatment system based on multiphase extraction and combined ventilation aeration. BACKGROUND

[0002] The multiphase extraction (MPE) technology is an important remediation technology for site remediation when the non-aqueous phase liquid NAPLs phase exists, which is an in-situ soil and groundwater remediation technology for processing by simultaneously extracting the contaminated soil gas, contaminated groundwater and non-aqueous phase liquid in the underground aeration zone and saturated zone to the ground. The MPE technology has relatively wide technical applicability. There are many precedents for using the MPE technology to remediate gas station plots abroad. Through vacuum extraction, the soil gas, groundwater and oil layer in the underground contaminated area are extracted to the ground for multiphase separation and processing, so as to control and remediate the organic pollutants in the soil and groundwater.

[0003] The traditional multiphase extraction system is divided into single-pump system and double-pump system. The single-pump system only uses a vacuum pump to simultaneously complete the extraction of the gas and liquid in the underground contaminated area, and the system configuration is simple, but there are problems such as limited drawdown of groundwater level during remediation, small influence radius, low extraction rate of groundwater and soil gas, and difficulty in remediation of deep soil and groundwater. The double-pump system needs to configure a vacuum pump and an extraction water pump to extract the gas and liquid in the underground contaminated area respectively, which can effectively overcome the limitations of the extraction depth of the single-pump system, has a large influence radius, the extraction rate can be freely adjusted, and has good remediation effect and flexibility.

[0004] The groundwater aeration (AS) technology is used for treating soil and groundwater contaminated by volatile organic pollutants, and fresh air or ozone is injected into the saturated zone by an air blower. Under the action of buoyancy, the air carries the gas-phase pollutants and gradually rises, and then the air carrying the pollutants is processed.

[0005] In actual operation, the input end of the air injection pipe of the combined ventilation and aeration unit and the output end of the air extraction and circulation unit are connected by flanges and bolts during installation. This way is time-consuming and laborious, and is very inconvenient. The stability after installation and connection is also poor. SUMMARY

[0006] To solve the technical problems in the background art, the present application provides a contaminated site treatment system based on multiphase extraction and combined ventilation aeration.

[0007] The present application adopts the following technical scheme: a contaminated site treatment system based on multiphase extraction and combined ventilation aeration, comprising:

[0008] a multi-phase extraction unit for extracting contaminated soil gas, contaminated groundwater and non-aqueous phase liquid in the vadose zone and saturated zone of the contaminated site to the ground for treatment;

[0009] a combined ventilation and aeration unit for injecting gas into the vadose zone of the contaminated site;

[0010] a tail gas treatment unit for treating tail gas to a preset standard and discharging into the atmosphere; and

[0011] a gas extraction and circulation unit for injecting the gas extracted by the multi-phase extraction unit into the combined ventilation and aeration unit or discharging from the tail gas treatment unit;

[0012] The combined ventilation and aeration unit comprises a gas injection well and / or an aeration well, and a gas injection pipe is arranged corresponding to the gas injection well and / or the aeration well, and the input end of the gas injection pipe is connected to the output end of the gas extraction and circulation unit through a locking device.

[0013] As a further improvement of the above scheme, the multi-phase extraction unit comprises an extraction well, and a gas phase output interface is arranged corresponding to the extraction well, and the gas phase output interface is connected to the gas extraction and circulation unit; an extraction pump is arranged in the extraction well.

[0014] As a further improvement of the above scheme, the output end of the extraction pump is sequentially connected to a buffer tank and an oil-water separator, and an oil collecting container and a water output channel are arranged corresponding to the oil-water separator.

[0015] As a further improvement of the above scheme, a water treatment device is arranged corresponding to the water output channel.

[0016] As a further improvement of the above scheme, the extraction pump is arranged in the saturated zone below the groundwater level of the contaminated site.

[0017] As a further improvement of the above scheme, gas holes are arranged on the well wall of the gas injection well, and the gas holes and the output end of the gas injection pipe are arranged in the vadose zone of the contaminated site.

[0018] As a further improvement of the above scheme, gas holes are arranged on the well wall of the aeration well, and the gas holes are arranged in the vadose zone and the saturated zone of the contaminated site, and the output end of the gas injection pipe is arranged in the saturated zone of the contaminated site.

[0019] As a further improvement of the above scheme, a gas pressure sensor is arranged corresponding to the gas injection well and / or the aeration well; an exhaust port is arranged at the wellhead, and a tail gas treatment mechanism is arranged corresponding to the exhaust port.

[0020] As a further improvement of the above scheme, the gas extraction and circulation unit is a gas extraction pump, and a gas sensor is arranged corresponding to the gas extraction pump; and an oxygen supplement port is arranged corresponding to the gas extraction pump.

[0021] As a further improvement of the above scheme, the locking device comprises a ring-shaped docking block coaxially arranged on the input end of the gas injection pipe, and a ring-shaped docking groove is arranged on the inner wall of the pipeline of the input end of the air extraction circulation unit and matched with the ring-shaped docking block.

[0022] Compared with the prior art, the present application has the following beneficial effects:

[0023] The pollution site treatment system based on multi-phase extraction and combined ventilation and aeration of the present application can efficiently complete the disassembly and assembly between the input end of the gas injection pipe and the output end of the air extraction circulation unit by additionally arranging the locking device therebetween, thereby saving time and effort and being stable and reliable. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 Structure schematic diagram of the system of the present application using a steam injection well;

[0025] Figure 2 Structure schematic diagram of the system of the present application using an aeration well;

[0026] Figure 3 Structure schematic diagram of the system of the present application using an aeration well; Figure 1 Structure schematic diagram of the system of the present application using an aeration well;

[0027] Figure 4 Structure schematic diagram of the system of the present application using an aeration well; Figure 3 Structure schematic diagram of the system of the present application using an aeration well;

[0028] Figure 5 Structure schematic diagram of the system of the present application using an aeration well; Figure 3 Structure schematic diagram of the system of the present application using an aeration well;

[0029] Figure 6 Structure schematic diagram of the system of the present application using an aeration well; Figure 3 Structure schematic diagram of the system of the present application using an aeration well;

[0030] Figure 7 Structure schematic diagram of the system of the present application using an aeration well; Figure 3 Structure schematic diagram of the system of the present application using an aeration well. DETAILED DESCRIPTION

[0031] Hereinafter, the present application will be further described in conjunction with the drawings and specific embodiments, and it should be noted that the following described embodiments or technical features can be combined in any manner to form new embodiments without conflict.

[0032] Embodiment 1

[0033] Please combine Figures 1-2, a contaminated site treatment system based on multi-phase extraction and combined ventilation aeration, comprising:

[0034] a multi-phase extraction unit for extracting contaminated soil gas, contaminated groundwater and non-aqueous phase liquid in the vadose zone and saturated zone of the contaminated site to the ground for treatment.

[0035] a combined ventilation and aeration unit for injecting gas into the vadose zone of the contaminated site.

[0036] a tail gas treatment unit for treating tail gas to a preset standard and discharging it into the atmosphere.

[0037] a gas extraction circulation unit for injecting the gas extracted by the multi-phase extraction unit into the combined ventilation and aeration unit or discharging it from the tail gas treatment unit.

[0038] In this embodiment, the technical and economic efficiency of site remediation is improved by reasonable layout of the combined ventilation and aeration unit. Specifically, the contaminated soil gas extracted by the multi-phase extraction unit is output from the gas extraction circulation unit to the combined ventilation and aeration unit and the tail gas treatment unit according to a preset rule, and the contaminated groundwater and non-aqueous phase liquid extracted by the multi-phase extraction unit are disposed after treatment, which makes up for the defects of limited influence radius and declining late-stage efficiency of single MPE technology, and improves the technical accessibility and remediation effect by conversion and cooperation of MPE technology with injection or AS technology at different remediation stages.

[0039] The combined ventilation and aeration unit includes an injection well 11 and / or an aeration well 12, and an injection pipe 13 is arranged corresponding to the injection well and / or the aeration well. The input end of the injection pipe is connected to the output end of the gas extraction circulation unit through a locking device, which can conveniently realize the disassembly and assembly of the input end of the injection pipe and the output end of the gas extraction circulation unit, and is stable and reliable after docking.

[0040] The multi-phase extraction unit includes an extraction well 10, and a gas phase output interface is arranged corresponding to the extraction well and connected to the gas extraction circulation unit 3. An extraction pump 4 is arranged in the extraction well.

[0041] The output end of the extraction pump 4 is sequentially connected to a buffer tank 5 and an oil-water separator 6, and an oil collecting container 7 and a water output channel 8 are arranged corresponding to the oil-water separator.

[0042] A water treatment device 9 is arranged corresponding to the water output channel.

[0043] The extraction pump 4 is arranged in the saturated zone 2 below the groundwater level of the contaminated site.

[0044] The gas extraction circulation unit 3 is a gas extraction pump, and a gas sensor (not shown) is arranged corresponding to the gas extraction pump; and an oxygen supplement port (not shown) is arranged corresponding to the gas extraction pump.

[0045] In this embodiment, the gas phase output interface of the extraction well 10 is connected with the air extraction circulating unit 3, which is used to extract the contaminated soil gas in the unsaturated zone 1 and the saturated zone 2 of the contaminated site; the extraction pump 4 in the extraction well 10 is generally arranged in the saturated zone 2, which is used to extract the contaminated groundwater and non-aqueous phase liquid.

[0046] The air injection well is provided with an air hole on the well wall, and the air hole and the output end of the air injection pipe are arranged in the unsaturated zone of the contaminated site.

[0047] The air injection well is provided with an air hole on the well wall, and the air hole and the output end of the air injection pipe are arranged in the unsaturated zone of the contaminated site.

[0048] The air injection well and / or the air injection well are provided with an air pressure sensor. An exhaust port is arranged at the well mouth, and a tail gas treatment mechanism 14 is arranged corresponding to the exhaust port. The air pressure sensor of the air injection well 11 tests the air pressure in the air injection well 11 in real time, and adjusts the air output of the air extraction pump and the exhaust amount at the exhaust port to stabilize the pressure. The outflowing gas is purified by the tail gas treatment mechanism 14 to meet the standard and then discharged.

[0049] The air extraction circulating unit is an air extraction pump, and a gas sensor is arranged corresponding to the air extraction pump. An oxygen supplement port is arranged corresponding to the air extraction pump.

[0050] The locking device includes an annular butt joint block 15 coaxially arranged on the input end of the air injection pipe 13, and an annular butt joint groove 16 is arranged on the inner wall of the pipeline of the input end of the air extraction circulating unit 3. The annular butt joint block 15 on the input end of the air injection pipe 13 is inserted into the annular butt joint groove 16 on the inner wall of the pipeline of the output end of the air extraction circulating unit 3 to complete the butt joint and fixation between the input end of the air injection pipe 13 and the output end of the air extraction circulating unit 3.

[0051] Embodiment 2

[0052] Please combine Figures 3-7 A first fixed block 17 and a limiting sleeve 32 are arranged on the outer wall of the air injection pipe 13, a first movable block 18 is slidably arranged on the first fixed block 17 along the radial direction of the air injection pipe 13, a through hole 19 is arranged on the first movable block 18,

[0053] The first column 21 is axially parallel to the gas injection pipe 13, and one end of the first column 21 is provided with a first pressure block 33. A first spring is arranged outside the first column 21, and two ends of the first spring are connected to the outer wall of the first pressure block 33 and the outer wall of the limiting sleeve 32 respectively. The first slope 20 is arranged on the orifice wall of the through hole 19 close to the first spring. The notch 22 is arranged on the first column 21, and the outer wall of the notch 22 close to the limiting sleeve 32 is in sliding and extrusion fit with the first slope 20. The first link 23 is coaxially arranged on the other end of the first column 21, and the clamping block 24 is arranged on the outer wall of the first link 23. The second fixed block 25 is arranged on the outer wall of the gas extraction and circulation unit 3, and the second movable block 26 which can move radially along the gas injection pipe 13 is arranged on the side of the second fixed block 25 facing the first fixed block 17. The second spring is arranged between the centrifugal end of the second movable block 26 and the block wall of the second fixed block 25. The first insertion slot 27 is arranged on the second movable block 26, and the clamping slot 29 is arranged on the second movable block 26. The orifice of the first insertion slot 27 is in sliding and extrusion fit with the second slope 28 after contacting the clamping block 24. The swing arm 30 is rotatably arranged on the first fixed block 17, and the push rod 31 which can be in extrusion fit with the first pressure block 33 after contacting the first pressure block 33 is arranged on the swing arm 30.

[0054] In this embodiment, when the docking installation between the gas injection pipe 13 and the gas extraction and circulation unit 3 needs to be completed, the predetermined positioning between the gas injection pipe 13 and the gas extraction and circulation unit 3 is first completed through the annular docking block 15 and the annular docking groove 16. Then, the swing arm 30 drives the push rod 31 to extrude the first pressure block 33, forcing the first column 21 to move towards the second fixed block 25 (the first spring is compressed), so that the outer wall of the notch 22 contacts and extrudes the first slope 20, causing the first movable block 18 to move centrifugally, so that the notch 22 can pass through the through hole 19, ensuring that the first column 21 can continue to move axially relative to the first movable block 18. Then, the first column 21 can drive the clamping block 24 to contact and extrude the second slope 28 of the second movable block 26 through the first link 23, forcing the second movable block 26 to move centrifugally (the second spring is compressed), so that the clamping block 24 can be inserted into the first insertion slot 27. When the clamping block 24 is completely inserted into the first insertion slot 27, the second movable block 26 will move centripetally under the action of the release of the second spring, so that the clamping block 24 and the clamping slot 29 are in mutual clamping, thereby realizing the docking and fixing between the gas injection pipe 13 and the gas extraction and circulation unit 3.

[0055] Further, in order to improve the sealing performance of the gas injection pipe 13 and the gas extraction circulating unit 3 after docking, a rack 39 is radially inserted on the outer wall of the gas injection pipe 13, the rack 39 is fixedly connected between the centrifugal end and the centripetal end of the first moving block 18, a transmission gear 40 matched with the rack 39 is rotatably arranged inside the pipe wall of the gas injection pipe 13, a first bevel gear 41 is coaxially fixed on the transmission gear 40, a cylinder 43 parallel to the axial direction of the gas injection pipe 13 is rotatably arranged in the pipe wall, a second bevel gear 42 matched with the first bevel gear 41 is arranged at one end of the cylinder 43, a screw rod 44 is threadedly inserted at the other end of the cylinder 43, an annular groove 47 is circumferentially arranged on the outer circumferential wall of the annular docking block 15, a capsule 48 completely covering the groove is arranged at the groove opening of the annular groove 47, a pressure space is formed between the inner side of the capsule 48 and the groove wall of the annular groove 47, and hydraulic oil is accommodated in the pressure space. A plug groove 45 communicating with the annular groove 47 is arranged in the annular docking block 15, a piston 46 is arranged in the plug groove 45, and one end of the screw rod 44 extends into the plug groove 45 and is fixed on the piston 46. A sealing groove 49 matched with the capsule 48 after expansion and deformation is arranged on the groove wall of the annular docking groove 16.

[0056] In the embodiment, when the gas injection pipe 13 and the gas extraction circulating unit 3 are docked, the centrifugal movement of the first moving block 18 can drive the rack 39 to drive the transmission gear 40, the first bevel gear 41, the second bevel gear 42 and the cylinder 43 to rotate, so that the cylinder 43 and the screw rod 44 are threadedly connected with each other to drive the piston 46 to extrude the hydraulic oil in the plug groove 45 into the annular groove 47, so that the pressure in the annular groove 47 increases to force the capsule 48 to expand and deform to be in sealing engagement with the sealing groove 49. This not only makes the connection between the gas injection pipe 13 and the gas extraction circulating unit 3 more stable, but also improves the sealing performance after docking.

[0057] Further, the second column 34 parallel to the first column 21 is slidably inserted on the first moving block 18, the second column 34 is provided with a second pressure receiving block 35 at one end, the third spring is sleeved outside the second column 34, and the two ends of the third spring are connected to the outer wall of the second pressure receiving block 35 and the outer wall of the first moving block 18. A second connecting rod 36 is coaxially fixed at the other end of the second column 34, the second connecting rod 36 is provided with a pressing block 37 on the outer wall, a second insertion slot 38 is arranged on the second moving block 26, and the second insertion slot 38 is provided with a third slope 381 in sliding extrusion cooperation with the pressing block 37 after contact.

[0058] When the connection between the injection pipe 13 and the air extraction circulating unit 3 needs to be released, the swing arm 30 is rotated to make the push rod 31 on the swing arm 30 press the second pressure block 35 (the third spring is compressed), so that the second cylinder 34 drives the pressing block 37 to press the third slope 381 through the second connecting rod 36, and the second moving block 26 moves away from the center (the second spring is compressed). When the pressing block 37 completely enters the second slot 38, the clamping block 24 is completely released from the clamping groove 29 and enters the first slot 27, and the elastic force of the first spring is released to drive the first pressure block 33, the first cylinder 21, the first connecting rod 23 and the clamping block 24 to move reversely, so that the clamping block 24 is completely released from the first slot 27, the gap 22 is moved to the first moving block 18, the first moving block 18 is moved to the center, the through hole 19 of the first moving block 18 and the gap 22 are engaged with each other, the first moving block 18 is moved to the center to drive the rack 39 to move to the center, the rack 39 drives the transmission gear 40, the first bevel gear 41, the second bevel gear 42 and the cylinder 43 to rotate reversely, the cylinder 43 and the screw rod 44 are screwed with each other to drive the piston 46 to move reversely in the plug groove 45, part of the hydraulic oil is extracted from the annular groove 47, the pressure in the annular groove 47 is reduced to force the capsule 48 to shrink and deform, the clamping and sealing cooperation between the capsule 48 and the sealing groove 49 is released, the annular abutting block 15 and the annular abutting groove 16 are separated, and the connection between the injection pipe 13 and the air extraction circulating unit 3 is released, which is convenient to disassemble and assemble.

[0059] The above-mentioned embodiments are only preferred embodiments of the present application, and cannot be used to limit the protection scope of the present application. Any non-essential changes and replacements made by those skilled in the art based on the present application are within the protection scope of the present application.

Claims

1. A contaminated site treatment system based on multiphase extraction and combined vented aeration, characterized in that, The application relates to a multi-phase extraction unit for extracting contaminated soil gas, contaminated groundwater and non-water phase liquid in the vadose zone and saturated zone of a contaminated site to the ground for treatment, a combined ventilation and aeration unit for injecting gas into the vadose zone of the contaminated site, a tail gas treatment unit for treating tail gas to a preset standard and discharging the tail gas into the atmosphere, and a gas extraction circulation unit for injecting the gas extracted by the multi-phase extraction unit into the combined ventilation and aeration unit or discharging the gas from the tail gas treatment unit. The combined ventilation and aeration unit comprises a gas injection well and / or an aeration well, and a gas injection pipe is arranged corresponding to the gas injection well and / or the aeration well, and the input end of the gas injection pipe is connected with the output end of the gas extraction circulation unit through a locking device. The locking device comprises an annular butt joint block coaxially arranged on the input end of the gas injection pipe, and an annular butt joint groove matched with the annular butt joint block is arranged on the inner wall of the pipeline of the input end of the gas extraction circulation unit. First fixing blocks and limiting sleeves are arranged on the outer wall of the gas injection pipe, a first movable block is slidably arranged on the first fixing blocks along the radial direction of the gas injection pipe, and a through hole is arranged on the first movable block. A first column body parallel to the axial direction of the gas injection pipe is slidably arranged in the limiting sleeve, one end of the first column body is provided with a first pressure bearing block, a first spring is arranged outside the first column body, the two ends of the first spring are connected with the outer wall of the first pressure bearing block and the outer wall of the limiting sleeve, the hole wall of the through hole near the first spring is provided with a first slope, a notch is arranged on the first column body and used for abutting against the first movable block, and the outer wall of the notch near the limiting sleeve is in sliding and extrusion fit with the first slope after being contacted with the first slope. A first connecting rod is coaxially arranged on the other end of the first column body, a clamping block is arranged on the outer wall of the first connecting rod, a second fixing block is arranged on the outer wall of the gas extraction circulation unit, a second movable block capable of moving along the radial direction of the gas injection pipe is slidably arranged on the side of the second fixing block facing the first fixing block, and a second spring is arranged between the centrifugal end of the second movable block and the block wall of the second fixing block. A first insertion slot is arranged on the second movable block and used for inserting the clamping block, a clamping slot matched with the clamping block is arranged on the second movable block, and the slot wall of the first insertion slot is provided with a second slope in sliding and extrusion fit with the clamping block after being contacted with the clamping block. A swing arm is rotatably arranged on the first fixing block, and a push rod capable of being in extrusion fit with the first pressure bearing block after being contacted with the first pressure bearing block is arranged on the swing arm. The multi-phase extraction unit comprises an extraction well, a gas phase output interface is arranged corresponding to the extraction well, the gas phase output interface is connected with the gas extraction circulation unit, and an extraction pump is arranged in the extraction well. The output end of the extraction pump is sequentially connected with a buffer tank and an oil-water separator, an oil collecting container and a water output channel are arranged corresponding to the oil-water separator. A water treatment device is arranged corresponding to the water output channel. The extraction pump is arranged in the saturated zone below the groundwater level of the contaminated site. Air holes are arranged on the well wall of the gas injection well, and the air holes and the output end of the gas injection pipe are arranged in the vadose zone of the contaminated site.

2. The multiphase extraction and combined venting-aeration based treatment system for contaminated sites of claim 1, wherein, Air holes are arranged on the well wall of the aeration well, the air holes are arranged in the vadose zone and the saturated zone of the contaminated site, and the output end of the gas injection pipe is arranged in the saturated zone of the contaminated site.

3. The multiphase extraction and combined venting-aeration based treatment system for contaminated sites as claimed in claim 2, wherein, A gas pressure sensor is arranged corresponding to the gas injection well and / or the aeration well, an exhaust port is arranged at the well mouth, and a tail gas treatment mechanism is arranged corresponding to the exhaust port.

4. The multiphase extraction and combined venting-aeration based treatment system for contaminated sites of claim 3, wherein, ​ 5. The multiphase extraction and combined venting-aeration based treatment system for contaminated sites of claim 2, wherein, ​ 6. The multiphase extraction and combined venting-aeration based treatment system for contaminated sites of claim 1, wherein, ​ 7. The multiphase extraction and combined venting-aeration based treatment system for contaminated sites of claim 1, wherein, ​ 8. The multiphase extraction and combined venting-aeration based treatment system for contaminated sites of claim 1, wherein, ​ 9. The multiphase extraction and combined venting-aeration based treatment system for contaminated sites of claim 1, wherein, The air extraction circulating unit is an air extraction pump, and a gas sensor is arranged in cooperation with the air extraction pump; and an oxygen supplement port is arranged corresponding to the air extraction pump.

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