A device for ozone-enhanced aeration remediation of contaminated soil

Abstract

This invention discloses an ozone-assisted aeration remediation device for contaminated soil, comprising an aeration pipe inserted into the contaminated area of ​​the soil containing volatile organic compounds (VOCs). An air supply device, a mixing chamber, and the aeration pipe are connected sequentially according to the gas delivery direction. The air supply device generates compressed gas at a predetermined pressure. An ozone generator produces ozone that can oxidize and reduce VOCs and delivers it to the mixing chamber. The mixing chamber contains an auxiliary device for mixing the compressed gas and ozone. An extraction device extracts and collects VOCs volatilized under the action of ozone-assisted aeration from the contaminated area of ​​the soil. By adding a mixing chamber to the air delivery path of the aeration pipe and introducing ozone into the mixing chamber, and utilizing the auxiliary device to fully mix the ozone with the compressed gas, chemical oxidation-reduction is performed based on traditional aeration technology, increasing the removal efficiency of various types of VOCs and ensuring remediation effectiveness.

Description

Technical Field

[0001] This invention relates to the field of groundwater and soil organic pollutant remediation technology, and in particular to an ozone-enhanced aeration remediation device for contaminated soil. Background Technology

[0002] In today's era of rapid development, all industries have achieved new leaps forward. However, the pollution problems arising from this development have also become increasingly prominent.

[0003] Aeration technology, due to its advantages of simple operation, high efficiency, and environmental friendliness, is one of the most effective methods for remediating groundwater contaminated with volatile organic compounds (VOCs), and has become one of the most effective methods for treating VOCs pollution in soil. Aeration remediation technology utilizes vertical or horizontal wells to inject compressed air into saturated contaminated soil. Through a gas-liquid-solid phase transfer process, pollutants evaporate from the soil or groundwater into the air. The pollutant-containing air rises continuously under buoyancy, reaching the unsaturated soil area above the groundwater level. Then, with the assistance of soil-gas extraction technology, this pollutant-containing air is extracted from the ground and treated on the surface, thereby achieving the remediation goal.

[0004] However, due to the complexity and non-uniformity of pollutants in soil, aeration methods often fail to achieve good remediation results, and the problem of organic pollutants with different properties and phases existing in soil is becoming increasingly serious. However, commercially available aeration devices can only achieve a certain degree of remediation for some organic pollutants in soil and cannot solve the problem of poor remediation effects for various organic pollutants during the aeration process. Summary of the Invention

[0005] To address the technical problems mentioned in the background section, this invention provides a device for ozone-enhanced aeration remediation of contaminated soil.

[0006] This invention is achieved using the following technical solution: a device for ozone-assisted aeration remediation of contaminated soil, comprising an aeration pipe, a mixing tank, a gas supply device, an ozone generator, and an extraction device. The aeration pipe is used to penetrate into the contaminated area of ​​the soil containing volatile organic compounds. The gas supply device, the mixing tank, and the aeration pipe are connected sequentially according to the gas delivery direction. The gas supply device is capable of generating compressed gas at a predetermined pressure. The ozone generator is used to generate ozone that can oxidize and reduce volatile organic compounds and deliver it to the mixing tank. The mixing tank has an auxiliary device capable of mixing the compressed gas and ozone. The extraction device is used to extract and collect the volatile organic compounds volatilized under the action of ozone-assisted aeration from the contaminated area of ​​the soil.

[0007] As a further improvement to the above solution, a drill bit is installed on the free end of the aeration pipe, and several aeration holes are distributed on the aeration pipe.

[0008] As a further improvement to the above solution, at least two detachable air supply pipe sections are provided on the input end of the aeration pipe, wherein the input end of the air supply pipe section furthest from the aeration pipe is connected to a second air outlet pipe, and the input end of the second air outlet pipe is connected to the mixing box.

[0009] As a further improvement to the above solution, two adjacent gas supply pipe sections are fixed together by threaded connection, and the output end of the gas supply pipe section is fixed together with the input end of the aeration pipe by threaded connection.

[0010] As a further improvement to the above solution, the air supply equipment includes an air compressor, the output end of which is connected to the first air injection pipe at the top of the mixing tank via a third air injection pipe.

[0011] As a further improvement to the above solution, the third gas injection pipe is equipped with a flow meter, a pressure regulating valve, and a switch in the direction of gas transmission.

[0012] As a further improvement to the above solution, the extraction device includes a pressure relief pipe that can penetrate into the vicinity of the soil contamination area. The output end of the pressure relief pipe is connected to a gas collection box, which can provide negative pressure to the pressure relief pipe. Multiple pressure relief holes that communicate with the interior of the pipe body are uniformly opened axially on the outer wall of the pressure relief pipe.

[0013] As a further improvement to the above solution, the output end of the ozone generator is connected to the second gas injection pipe at the top of the mixing box through the first gas outlet pipe, and a water vapor separator is installed on the first gas outlet pipe.

[0014] As a further improvement to the above solution, the auxiliary device includes a partition, which is disposed inside the mixing chamber and divides the mixing chamber into a first region and a second region from top to bottom.

[0015] A first cylinder is provided on the top wall of the first region. The first cylinder has a first cavity inside. Multiple downwardly inclined nozzles are provided on the outside of the first cylinder. The nozzles are connected to the first cavity. A first connecting pipe is inserted into the top of the mixing box. The input end of the first connecting pipe is connected to the output end of the second air injection pipe. The output end of the first connecting pipe is connected to the first cavity.

[0016] A second cylinder, concentric with the first cylinder, is rotatably inserted into the partition plate. The second cylinder has a second cavity and a third cavity that communicate with each other from bottom to bottom. The diameter of the second cavity is smaller than that of the third cavity. A third connecting pipe is provided at the top of the second cylinder, rotating synchronously with it. The bottom of the third connecting pipe is connected to the third cavity. Multiple upwardly inclined nozzles are provided on the outer wall of the third connecting pipe. A second connecting pipe is provided on the mixing box. The input end of the second connecting pipe is connected to the output end of the first air injection pipe. The output end of the second connecting pipe is connected to the second cavity. The second cylinder can rotate relative to the output end of the second connecting pipe.

[0017] The nozzle on the first cylinder has a nozzle orifice with a spray direction tilted downwards, while the nozzle on the third connecting pipe has a nozzle orifice with a spray direction tilted upwards.

[0018] The mixing chamber is equipped with a fourth connecting pipe, the input end of which is connected to the first region, and the output end of which is connected to the input end of the second air outlet pipe.

[0019] As a further improvement to the above solution, a motor is installed in the second region, a first gear is connected to the output shaft of the motor, and a second gear that matches the first gear is sleeved and fixed on the outer side of the second cylinder.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0021] The ozone-enhanced aeration remediation device for contaminated soil of the present invention adds a mixing box to the gas delivery path of the aeration pipe, and inputs ozone into the mixing box and uses an auxiliary device to fully mix the ozone with the compressed gas, so as to carry out chemical oxidation and reduction on the basis of traditional aeration technology, increase the removal efficiency of volatile organic pollutants of various properties, and ensure the remediation effect. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0023] Figure 2 for Figure 1 Schematic diagram of the drilling head and aeration pipe;

[0024] Figure 3 for Figure 1 A schematic diagram of the structure of a medium ozone generator;

[0025] Figure 4 for Figure 1 Schematic diagram of the structure of the mixing chamber;

[0026] Figure 5 for Figure 4A schematic diagram of the cross-sectional structure of the lower nozzle in the mixing chamber when it is close to the upper nozzle;

[0027] Figure 6 for Figure 5 A schematic diagram of the cross-sectional structure of the lower nozzle in the mixing chamber when it is far away from the upper nozzle;

[0028] Figure 7 for Figure 5 Enlarged structural diagram at point A;

[0029] Figure 8 for Figure 5 A schematic diagram of the groove structure presented by the circumferentially unfolded slot of the Lieutenant General's slot.

[0030] Explanation of key symbols:

[0031] 1. Drill bit; 2. Aeration pipe; 3. Aeration hole; 5. Gas delivery pipe section; 7. Ozone generator; 8. Radiator; 9. Water vapor separator; 10. Mixing box; 11. Backflow valve; 12. First air outlet pipe; 13. First air injection pipe; 14. Third air injection pipe; 15. Air compressor; 16. Flow meter; 17. Pressure regulating valve; 18. Switch; 19. Second air injection pipe; 20. Nozzle; 21. Second air outlet pipe; 22. Pressure relief pipe; 23. Air collection box; 24. 25. Pressure relief hole; 26. Soil; 27. Partition plate; 28. First connecting pipe; 29. ​​First cylinder; 30. First cavity; 31. Spray hole; 32. Second connecting pipe; 33. Pipe rotary joint; 34. Second cylinder; 35. Third cavity; 36. Third connecting pipe; 37. Motor; 38. First gear; 39. Second gear; 40. Insert rod; 41. Slot; 42. Groove; 43. Protrusion; 44. Fourth connecting pipe. Detailed Implementation

[0032] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0033] Example 1

[0034] Please combine Figures 1 to 8The ozone-assisted aeration remediation device for contaminated soil includes an aeration pipe 2, a mixing tank 10, an air supply device, an ozone generator 7, and an extraction device. The aeration pipe 2 is used to penetrate into the contaminated area of ​​the soil 25 containing volatile organic compounds. The air supply device, the mixing tank 10, and the aeration pipe 2 are connected in sequence according to the gas delivery direction. The air supply device can generate compressed gas with a predetermined pressure. The ozone generator 7 is used to generate ozone that can oxidize and reduce volatile organic compounds and deliver it to the mixing tank 10. The mixing tank 10 has an auxiliary device that can mix the compressed gas and ozone evenly. The extraction device is used to extract and collect the volatile organic compounds volatilized under the action of ozone assisted aeration from the contaminated area of ​​the soil.

[0035] A drill bit 1 is installed on the free end of the aeration pipe 2, and several aeration holes 3 are distributed on the aeration pipe 2. The drill bit 1 and the aeration pipe 2 are integrated into one structure. The drill bit 1 is in the shape of a threaded drill bit.

[0036] At least two detachable air supply pipe sections 5 are provided on the inlet end of the aeration pipe 2. The air supply pipe sections 5 are pressure-resistant stainless steel pipes with uniform segments. The inlet end of the air supply pipe section 5 furthest from the aeration pipe 2 is connected to the second air outlet pipe 21, and the inlet end of the second air outlet pipe 21 is connected to the mixing box 10.

[0037] Two adjacent gas delivery pipe sections 5 are fixed together by threaded connection, and the output end of the gas delivery pipe section 5 is fixed together with the input end of the aeration pipe 2 by threaded connection. That is, the gas delivery pipe sections 5 can be connected together by internal and external threads, and the number of gas delivery pipe sections 5 can be increased according to the soil depth to be repaired.

[0038] The mixing chamber 10 is equipped with a first gas injection pipe 13 for compressed gas input and a second gas injection pipe 19 for ozone input. Both the first gas injection pipe 13 and the second gas injection pipe 19 are equipped with backflow valves 11 to prevent gas backflow in the mixing chamber 10.

[0039] The air supply equipment includes an air compressor 15, and the output end of the air compressor 15 is connected to the first air injection pipe 13 at the top of the mixing box 10 through the third air injection pipe 14.

[0040] The third gas injection pipe 14 is equipped with a flow meter 16, a pressure regulating valve 17, and a switch 18 in the direction of gas transmission.

[0041] The extraction device includes a pressure relief pipe 22 that can penetrate into the vicinity of the contaminated area of ​​the soil 25. The output end of the pressure relief pipe 22 is connected to a gas collection box 23, which provides negative pressure to the pressure relief pipe 22. A negative pressure pump is installed in the gas collection box 23. Multiple pressure relief holes 24, communicating with the interior of the pipe body, are evenly distributed axially on the outer wall of the pressure relief pipe 22. The depth of the pressure relief pipe 22 is parallel to the entire contaminated area and is the same depth as the gas transmission pipe section 5. The gas collection box 23 is connected to the pressure relief pipe 22 through corresponding pipes.

[0042] The output of the ozone generator 7 is connected to the second gas injection pipe 19 at the top of the mixing chamber 10 via the first gas outlet pipe 12, and a water vapor separator 9 is installed on the first gas outlet pipe 12. After being produced by the ozone generator 7, the ozone enters the mixing chamber 10 through the first gas outlet pipe 12 and the water vapor separator 9 to participate in the mixing with the compressed gas.

[0043] The ozone generator 7 is equipped with multiple heat sinks 8, which can be fans. The heat sinks 8 are installed on both sides of the ozone generator 7 to cool the machine and prevent it from overheating during operation.

[0044] The auxiliary device includes a partition 26, which is disposed inside the mixing chamber 10 and divides the mixing chamber 10 into a first region (not shown) and a second region (not shown) from top to bottom.

[0045] A first cylinder 28 is fixed to the top wall of the first region, and the position of the first cylinder 28 in the mixing box 10 is fixed. The first cylinder 28 has a first cavity 29 inside, and multiple downwardly inclined nozzles 20 are arranged on the outside of the first cylinder 28. The nozzles 20 are connected to the first cavity 29. A first connecting pipe 27 is inserted into the top of the mixing box 10. The input end of the first connecting pipe 27 is connected to the output end of the second air injection pipe 19, and the output end of the first connecting pipe 27 is connected to the first cavity 29.

[0046] A second cylinder 33, concentric with the first cylinder 28, is rotatably inserted on the partition 26. The second cylinder 33 has a second cavity 34 and a third cavity 35 that are interconnected from bottom to bottom. The diameter of the second cavity 34 is smaller than that of the third cavity 35. A third connecting pipe 36 is provided on the top of the second cylinder 33 and rotates synchronously with it. The bottom of the third connecting pipe 36 is connected to the third cavity 35. Multiple upwardly inclined nozzles 20 are provided on the outer wall of the third connecting pipe 36. A second connecting pipe 31 is provided on the mixing box 10. The input end of the second connecting pipe 31 is connected to the output end of the first air injection pipe 13, and the output end of the second connecting pipe 31 is connected to the second cavity 34. The second cylinder 33 can rotate relative to the output end of the second connecting pipe 31.

[0047] In this embodiment, the bottom of the second cylinder 33 is connected to the output end of the second connecting pipe 31 through the pipe rotary joint 32, so the second cylinder 33 can rotate relative to the output end of the second connecting pipe 31, and the output end of the second connecting pipe 31 is connected to the second cavity 34.

[0048] The nozzle 20 on the first cylinder 28 has a nozzle 30 with the spray direction tilted downwards, while the nozzle 20 on the third connecting pipe 36 has a nozzle 30 with the spray direction tilted upwards. This allows compressed gas to be sprayed from bottom to top and ozone to be sprayed from top to bottom, causing convection between the two, increasing the contact between particles, and improving the mixing effect and efficiency.

[0049] A fourth connecting pipe 44 is installed on the mixing chamber 10. The input end of the fourth connecting pipe 44 is connected to the first region, and the output end of the fourth connecting pipe 44 is connected to the input end of the second outlet pipe 21. The mixed compressed gas and ozone can be transported to the aeration pipe 2 through the second outlet pipe 21.

[0050] A motor 37 is installed in the second area. A first gear 38 is connected to the output shaft of the motor 37. A second gear 39, which is matched with the first gear 38, is sleeved and fixed on the outside of the second cylinder 33.

[0051] The output shaft of motor 37 can drive the first gear 38, the second gear 39, the second cylinder 33, the third connecting pipe 36 and the corresponding nozzle 20 to rotate. While spraying compressed gas upward, it can also make the nozzle 20 rotate in a manner equivalent to a stirring paddle to promote the mixing of ozone and compressed gas.

[0052] The operation steps of the ozone-co-aeration remediation device in this embodiment are as follows:

[0053] Step 1: Determine the location and distribution range of the contaminated area containing volatile organic pollutants;

[0054] Specifically, in this implementation case, the contaminated area of ​​volatile organic pollutants is distributed in saturated soil at a depth of 1-1.5 meters underground, with a thickness of about 0.5m.

[0055] Step 2: Installation of the aeration and repair device

[0056] Specifically, a portable drilling rig is used to insert the pre-connected drill bit 1, along with the aeration pipe 2 and the air delivery pipe section 5, into the soil 25, so that the aeration is placed in the polluted area of ​​volatile organic pollutants.

[0057] Step 3, Connecting the ozone generator

[0058] Specifically, place the ozone generator 7 in the mixing chamber 10 and connect the first outlet pipe 12 to the mixing chamber 10. Install the radiator 8 on both side walls of the ozone generator 7 and connect it to the power supply to start operation.

[0059] Step 4: Installation of the gas mixing device

[0060] Specifically, the mixing box 10 is installed on top of the gas supply pipe section 5; the first gas injection pipe 13 and the second gas injection pipe 19 on the top of the mixing box 10 are respectively connected to the air compressor 15 and the ozone generator 7.

[0061] Step 5, begin aeration.

[0062] Start the air compressor 15 and adjust the pressure regulating valve 17 to the predetermined aeration pressure.

[0063] When switch 18 and ozone generator 7 are turned on, both ozone and compressed gas enter the mixing box 10 for mixing. After mixing, the compressed gas and ozone are transported to aeration pipe 2 and released from the evenly distributed aeration holes 3, forming a seepage channel in the polluted area of ​​volatile organic pollutants. Volatile organic pollutants diffuse into the seepage channel. A portion volatilizes through the evenly distributed pressure relief holes 24 on the wall of pressure relief pipe 22 to the gas collection box 23 for treatment. A portion of complex organic pollutants undergoes an oxidation-reduction reaction with ozone and volatilizes into the unsaturated area, finally volatilizing through pressure relief pipe 22 to the gas collection box 23 for treatment, thereby achieving the removal of volatile organic pollutants from soil 25.

[0064] The aeration device and ozone-coordinated aeration method of this embodiment can greatly improve the aeration efficiency and VOCs removal rate on the basis of traditional aeration work.

[0065] Example 2

[0066] This embodiment is an improvement on Embodiment 1. The bottom of the third connecting pipe 36 is slidably engaged in the third cavity 35 of the second cylinder 33, and can rotate synchronously with the second cylinder 33 while also moving axially relative to the second cylinder 33. A sealing ring is fitted on the outer side of the bottom of the third connecting pipe 36 to ensure the sealing performance when the third connecting pipe 36 moves relative to the second cylinder 33.

[0067] The top of the third connecting pipe 36 is concentrically fixed with a plug rod 40, and the bottom of the first cylinder 28 is provided with a slot 41 for inserting into the top of the plug rod 40. The inner wall of the slot 41 is provided with a groove 42 in a double figure-eight shape and a closed loop structure, and the outer wall of the plug rod 40 is provided with a protrusion 43 that slides and engages with the groove 42.

[0068] When the third connecting pipe 36 rotates, it can drive the protrusion 43 to continuously rub and squeeze the groove wall of the groove 42, which has a double figure-eight shape and a closed loop structure. Since the first cylinder 28 is fixed in position, the protrusion 43 can drive the third connecting pipe 36 to move axially back and forth relative to the third cavity 35 of the second cylinder 33 through the insertion rod 40 under the reaction force of the friction of the groove 42. This allows the nozzle 20 on the third connecting pipe 36 to move up and down back and forth while rotating, increasing the contact range between the nozzle 20 and the gas, and continuously changing the convective pressure between ozone and compressed gas, thereby improving the mixing effect and efficiency between ozone and compressed gas.

[0069] The above embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A device for ozone-enhanced aeration remediation of contaminated soil, characterized in that, The system includes an aeration pipe, a mixing chamber, an air supply device, an ozone generator, and an extraction device. The aeration pipe is used to penetrate into the soil in a contaminated area containing volatile organic compounds. The air supply device, the mixing chamber, and the aeration pipe are connected in sequence according to the gas delivery direction. The air supply device can generate compressed gas at a predetermined pressure. The ozone generator is used to generate ozone that can oxidize and reduce volatile organic compounds and deliver it to the mixing chamber. The mixing chamber has an auxiliary device that can mix the compressed gas and ozone evenly. The extraction device is used to extract and collect the volatile organic compounds volatilized under the synergistic aeration effect of ozone from the contaminated area of ​​the soil. The aeration pipe input end is provided with at least two detachable air supply pipe sections, wherein the input end of the air supply pipe section furthest from the aeration pipe is connected to a second air outlet pipe, and the input end of the second air outlet pipe is connected to the mixing box. The auxiliary device includes a partition, which is disposed inside the mixing chamber and divides the mixing chamber into a first region and a second region from top to bottom; A first cylinder is provided on the top wall of the first region. The first cylinder has a first cavity inside. Multiple downwardly inclined nozzles are provided on the outside of the first cylinder. The nozzles are connected to the first cavity. A first connecting pipe is inserted into the top of the mixing box. The input end of the first connecting pipe is connected to the output end of the second air injection pipe. The output end of the first connecting pipe is connected to the first cavity. A second cylinder, concentric with the first cylinder, is rotatably inserted into the partition plate. The second cylinder has a second cavity and a third cavity that communicate with each other from bottom to bottom. The diameter of the second cavity is smaller than that of the third cavity. A third connecting pipe is provided at the top of the second cylinder, rotating synchronously with it. The bottom of the third connecting pipe is connected to the third cavity. Multiple upwardly inclined nozzles are provided on the outer wall of the third connecting pipe. A second connecting pipe is provided on the mixing box. The input end of the second connecting pipe is connected to the output end of the first air injection pipe. The output end of the second connecting pipe is connected to the second cavity. The second cylinder can rotate relative to the output end of the second connecting pipe. The nozzle on the first cylinder has a nozzle orifice with a spray direction tilted downwards, while the nozzle on the third connecting pipe has a nozzle orifice with a spray direction tilted upwards. The mixing chamber is equipped with a fourth connecting pipe, the input end of which is connected to the first area, and the output end of which is connected to the input end of the second air outlet pipe. The top of the third connecting tube is concentrically fixed with a plug rod. The bottom of the first cylinder has a slot for inserting into the top of the plug rod. The inner wall of the slot has a groove with a double figure-eight shape and a closed loop structure. The outer wall of the plug rod has a protrusion that slides and engages with the groove.

2. The ozone-enhanced aeration remediation device for contaminated soil as described in claim 1, characterized in that, A drill bit is installed on the free end of the aeration pipe, and several aeration holes are distributed on the aeration pipe.

3. The ozone-enhanced aeration remediation device for contaminated soil as described in claim 1, characterized in that, The two adjacent gas supply pipe sections are fixed together by threaded connection, and the output end of the gas supply pipe section is fixed together with the input end of the aeration pipe by threaded connection.

4. The ozone-enhanced aeration remediation device for contaminated soil as described in claim 1, characterized in that, The air supply equipment includes an air compressor, and the output end of the air compressor is connected to the first air injection pipe at the top of the mixing box through a third air injection pipe.

5. The ozone-enhanced aeration remediation device for contaminated soil as described in claim 4, characterized in that, The third gas injection pipe is equipped with a flow meter, a pressure regulating valve, and a switch in the direction of gas transmission.

6. The ozone-enhanced aeration remediation device for contaminated soil as described in claim 1, characterized in that, The extraction device includes a pressure relief pipe that can penetrate into the vicinity of the soil contamination area. The output end of the pressure relief pipe is connected to a gas collection box, which can provide negative pressure to the pressure relief pipe. Multiple pressure relief holes that communicate with the interior of the pipe body are uniformly opened axially on the outer wall of the pressure relief pipe.

7. The ozone-enhanced aeration remediation device for contaminated soil as described in claim 1, characterized in that, The output end of the ozone generator is connected to the second gas injection pipe at the top of the mixing tank through the first gas outlet pipe, and a water vapor separator is installed on the first gas outlet pipe.

8. The ozone-enhanced aeration remediation device for contaminated soil as described in claim 1, characterized in that, A motor is installed in the second region, and a first gear is connected to the output shaft of the motor. A second gear, which is matched with the first gear, is sleeved and fixed on the outside of the second cylinder.

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