Tail gas treatment device and method based on negative pressure suction

Abstract

The invention discloses a tail gas treatment device and method based on negative pressure suction. The tail gas treatment device comprises a storage tank, the cryogenic oil gas treatment device is provided with a separation inlet, an exhaust port and a liquid discharge port; the mixing device is provided with a lean hydrocarbon inlet, an air inlet, a mixing outlet, a heat exchange inlet and a heat exchange outlet; the catalytic oxidation device is provided with a catalytic inlet and a catalytic outlet, and the catalytic outlet is communicated with the heat exchange inlet; and the conveying device comprises a driving mechanism and two conveying mechanisms and is used for introducing the outside air into the air inlet and inputting the hydrocarbon-lean gas into the hydrocarbon-lean inlet at the same time. According to the tail gas treatment device and method based on negative pressure suction, tail gas in the storage tank is introduced into the copious cooling oil gas treatment device through gas suction, hydrocarbon-poor gas is formed and then mixed with external air, then catalytic oxidation is conducted, generated high-temperature gas is used for preheating the hydrocarbon-poor gas and mixed gas, catalytic oxidation is promoted, meanwhile, environmental pollution is reduced, and the service life of the tail gas is prolonged. Heat energy generated by catalytic oxidation is fully utilized, and energy conservation and environmental protection are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of tail gas treatment, and in particular to a tail gas treatment device and method based on negative pressure suction. Background Art

[0002] Storage tanks are often used to temporarily store some hazardous chemical materials. After being used for a period of time, the storage tanks need to be cleaned to ensure their normal use.

[0003] However, during the storage of hazardous chemicals, some toxic and harmful tail gases are likely to be generated inside the storage tanks. Therefore, in order to ensure safety, meet the requirements of the operating environment, and prevent chemical reactions from occurring, it is necessary to ventilate and replace the gas inside the storage tanks. The tail gas generated after the storage tank is emptied usually contains high concentrations of volatile organic compounds (VOCs), carbon monoxide (CO), and a small amount of residual hydrocarbon substances. If directly discharged, it will not only seriously pollute the environment but also may pose a safety hazard.

[0004] Therefore, there is an urgent need for a tail gas treatment device and method for storage tanks. Summary of the Invention

[0005] The purpose of the present invention is to overcome the defects existing in the prior art and provide a tail gas treatment device and method based on negative pressure suction that are energy-saving, environmentally friendly, and reduce environmental pollution.

[0006] To solve the above technical problems, the present invention provides a tail gas treatment device based on negative pressure suction, including: A storage tank having a feed inlet, a discharge outlet, and a gas extraction port, and the feed inlet, the discharge outlet, and the gas extraction port are respectively connected with a feed valve, a discharge valve, and a gas extraction valve; A cryogenic oil and gas treatment device having a separation inlet, an exhaust outlet, and a liquid discharge port, and the liquid discharge port is connected with a liquid discharge valve; A mixing device having a lean hydrocarbon inlet, an air inlet, a mixing outlet, a heat exchange inlet, and a heat exchange outlet, and the lean hydrocarbon inlet is communicated with the exhaust outlet; A catalytic oxidation device having a catalytic inlet and a catalytic outlet, and the catalytic outlet is communicated with the heat exchange inlet; A conveying device including a driving mechanism and two conveying mechanisms. The driving mechanism is used to provide power to the two conveying mechanisms, so that while one conveying mechanism introduces external air into the air inlet, the other conveying mechanism inputs the lean hydrocarbon gas output from the exhaust outlet into the lean hydrocarbon inlet to mix the lean hydrocarbon tail gas with external air.

[0007] Preferably, in order to achieve continuous gas delivery, both of the said delivery mechanisms each include two facing delivery units. Each of the two delivery units includes a cylinder barrel and a piston that is hermetically connected to and slidably engaged with the inner wall of the cylinder barrel along the axial direction of the cylinder barrel. An inlet and an outlet are provided on the cylinder barrel, and two one-way valves with opposite directions are connected to the inlet and the outlet. The drive mechanism drives the pistons of the two delivery units in the delivery mechanism to move synchronously.

[0008] Preferably, in order to drive the pistons in the two delivery units to move synchronously, the drive mechanism includes a drive unit, a turntable, and two transmission units arranged on both sides of the turntable. The drive unit drives the turntable to rotate around its own axis. The two transmission units are respectively arranged on both sides of the turntable and are correspondingly connected to the two delivery mechanisms. The two transmission units include a convex shaft arranged on the turntable and having a spacing from the axis of the turntable, and a moving frame sleeved outside the convex shaft. The moving frame is fixedly connected to the pistons of the two delivery units in the corresponding delivery mechanism. The moving directions of the two moving frames are consistent with the distribution direction of the two delivery units in the delivery mechanism.

[0009] Preferably, in order to be able to adjust the delivery ratio of air and lean hydrocarbon gas, ensure the full oxidation of lean hydrocarbon gas, and at the same time avoid excessive air delivery affecting the later catalytic oxidation efficiency, an adjustment unit is provided between one of the convex shafts and the turntable to adjust the spacing between the convex shaft and the axis of the turntable. The other convex shaft is fixedly connected to the turntable. A flow sensor is connected to the lean hydrocarbon inlet.

[0010] Preferably, in order to be able to adjust the air delivery volume according to the lean hydrocarbon gas volume, the adjustment unit includes an adjustment motor arranged on the convex shaft. The adjustment motor is drivingly connected to a lead screw. The lead screw is threadedly connected to a nut sleeve. The convex shaft corresponding to the adjustment unit is fixed to the nut sleeve. A distance sensor for detecting the position of the nut sleeve is provided on the turntable.

[0011] Preferably, in order to achieve the preheating of lean hydrocarbon gas and the mixed gas, ensure that the mixed gas has a certain temperature after being discharged, and facilitate sufficient catalytic oxidation, the mixing device has a preheating chamber communicated with the air inlet and a heat exchange chamber communicated with the heat exchange outlet. A preheating coil is provided in the preheating chamber. The input end of the preheating coil is the preheating inlet, and the output end is communicated with the heat exchange chamber through a heat-insulating pipe. In the heat exchange chamber, an outer pipe is provided. Both ends of the outer pipe are respectively communicated with the heat-insulating pipe and the heat exchange outlet. An inner pipe penetrates through the inside of the outer pipe. Both ends of the inner pipe are respectively communicated with the lean hydrocarbon inlet and the preheating chamber.

[0012] Preferably, in order to achieve the full preheating of lean hydrocarbon gas, the outer pipes are densely arranged in the heat exchange chamber.

[0013] Preferably, in order to achieve the safe discharge of waste gas, the heat exchange outlet is arranged at the bottom of the mixing device and connected with a waste gas pipe extending downward, a waste liquid pool is arranged at the bottom of the mixing device, and the bottom of the waste gas pipe is arranged in the waste liquid pool.

[0014] Preferably, in order to ensure that clean air can be introduced and prevent soot in the air from mixing with the lean hydrocarbon gas and affecting the operation of the device, the conveying mechanism connected to the air inlet is connected with a filtering component at its input end.

[0015] To solve the above technical problems, the present invention also provides a tail gas treatment method based on negative pressure suction, including the following steps: S100, discharging: discharging the liquid hazardous chemicals in the storage tank; S200, air extraction: introducing the tail gas in the storage tank into a cryogenic oil and gas treatment device to discharge lean hydrocarbon gas; S300, mixing: introducing external air and lean hydrocarbon gas into a mixing device for mixing and discharging the mixed gas; S400, catalytic oxidation: catalytically oxidizing the mixed gas to discharge high-temperature waste gas; S500, drainage: introducing the waste gas into the mixing device to exchange heat with external air and lean hydrocarbon gas and then discharging it to the outside; The conveying mechanism used for tail gas conveying in step S200 and the conveying mechanism used for external air conveying in step 300 are both driven by the same driving mechanism.

[0016] In summary, compared with the prior art, the tail gas treatment device and method based on negative pressure suction of the present invention introduce the tail gas in the storage tank into a cryogenic oil and gas treatment device through air extraction, form lean hydrocarbon gas, mix it with external air, and then catalytically oxidize it. The generated high-temperature gas is used to preheat the lean hydrocarbon gas and the mixed gas, promoting catalytic oxidation while reducing environmental pollution, making full use of the heat energy generated by catalytic oxidation, and achieving energy conservation and environmental protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a schematic structural diagram of the present invention; Figure 2 is a top view of the present invention; Figure 3 is a schematic structural diagram of the present invention from another perspective; Figure 4 is a schematic structural diagram of the filtering component of the present invention; Figure 5 is Figure 4 the sectional structural diagram of Figure 6 is a schematic structural diagram of the conveying device of the present invention; Figure 7 It is a schematic structural diagram of another perspective of the conveying device of the present invention; Figure 8 It is Figure 7 an explosion schematic diagram of; Figure 9 It is a schematic structural diagram of the fixing frame in the conveying device of the present invention; Figure 10 It is a schematic structural diagram of the conveying unit in the conveying device of the present invention; Figure 11 It is Figure 10 a schematic cross-sectional structural diagram of; Figure 12 It is a schematic structural diagram of the driving mechanism of the present invention; Figure 13 It is Figure 12 an explosion schematic diagram of; Figure 14 It is a schematic connection structure diagram of the mixing device and the waste liquid pool of the present invention; Figure 15 It is Figure 14 an explosion schematic diagram of; Figure 16 It is Figure 14 an explosion schematic diagram of another perspective; Figure 17 It is a schematic structural diagram of the mixing device of the present invention; Figure 18 It is Figure 17 an explosion schematic diagram of; Figure 19 It is Figure 18 an explosion schematic diagram of another perspective; Figure 20 It is Figure 17 a schematic cross-sectional structural diagram of; Figure 21 It is Figure 20 an enlarged view of part A of; In the figure: 1. Storage tank; 11. Feed inlet; 12. Air extraction port; 13. Feed valve; 14. Air extraction valve; 15. Discharge port; 16. Discharge valve; 2. Cryogenic oil and gas treatment device; 21. Separation inlet; 22. Exhaust port; 23. Drainage port; 24. Drainage valve; 3. Mixing device; 301. Lean hydrocarbon inlet; 302. Air inlet; 3021. Air inlet pipe; 303. Mixing outlet; 304. Heat exchange inlet; 305. Heat exchange outlet; 3051. Exhaust pipe; 306. Flow sensor; 307. Preheating chamber; 308. Heat exchange chamber; 31. Preheating coil; 32. Outer pipe; 33. Inner pipe; 34. Support plate; 341. Support foot; 35. Heat insulation cover; 351. Heat insulation pipe; 36. Mixing box; 361. Mixing cover; 3611. Heat insulation outlet; 362. Diverter plate; 363. Air inlet cover; 364. Flow guide cover; 37. Heat exchange shell; 371. Outer shell cover; 3711. Heat insulation inlet; 372. Outer shell cover; 373. Inner shell cover; 374. Inner shell cover; 375. Closed channel; 376. Exhaust hood; 38. Partition board; 4. Catalytic oxidation device; 41. Catalytic inlet; 42. Catalytic outlet; 5. Driving mechanism; 51. Driving unit; 511. Driving motor; 512. Driving gear; 52. Turntable; 521. Support bearing; 53. Transmission unit; 531. Convex shaft; 532. Moving frame; 533. Connecting bar; 534. Sliding sleeve; 54. Adjusting unit; 541. Adjusting motor; 542. Lead screw; 543. Nut sleeve; 544. Distance sensor; 545. Support shaft sleeve; 6. Conveying mechanism; 61. Conveying unit; 611. Cylinder barrel; 6111. Inlet; 6112. Outlet; 612. Piston; 613. Check valve; 614. Filter screen; 62. Three-way pipe; 7. Waste liquid pool; 71. Waste discharge pipe; 72. Waste discharge valve; 73. Support inner frame; 74. Outer frame; 75. Sponge board; 8. Filter assembly; 81. Filter barrel; 811. Air inlet; 812. Waste discharge port; 813. Air inlet valve; 814. Waste discharge valve; 815. Inner convex ring; 82. Filter cover; 821. Air outlet; 822. Positioning pressure ring; 83. Filter element; 831. Turned-out edge; 84. Bolt; 85. Nut; 86. Connecting hose; 87. Collection box; 9. Fixed frame; 91. Bottom plate; 92. Motor frame; 93. Bracket; 94. Cross frame; 95. Frame; 951. Cross bar; 952. Vertical bar; 96. Bearing frame. Detailed implementation manners

[0018] The following combines the accompanying drawings and embodiments to further describe the detailed implementation manners of the present invention. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention and cannot be used to limit the protection scope of the present invention.

[0019] As Figures 1 - 21 shown, a tail gas treatment device based on negative pressure suction of the present invention includes: Storage tank 1, having a feed inlet 11, a discharge outlet 15 and a gas extraction port 12, the feed inlet 11, the discharge outlet 15 and the gas extraction port 12 are respectively connected with a feed valve 13, a discharge valve 16 and a gas extraction valve 14; Cryogenic oil and gas treatment device 2, having a separation inlet 21, an exhaust port 22 and a liquid discharge port 23, the liquid discharge port 23 is connected with a liquid discharge valve 24; Mixing device 3, having a lean hydrocarbon inlet 301, an air inlet 302, a mixing outlet 303, a heat exchange inlet 304 and a heat exchange outlet 305, the lean hydrocarbon inlet 301 is communicated with the exhaust port 22; Catalytic oxidation device 4, having a catalytic inlet 41 and a catalytic outlet 42, the catalytic outlet 42 is communicated with the heat exchange inlet 304; Conveying device, including a driving mechanism 5 and two conveying mechanisms 6, the driving mechanism 5 is used to provide power to the two conveying mechanisms 6, so that while one conveying mechanism 6 introduces external air into the air inlet 302, the other conveying mechanism 6 inputs the lean hydrocarbon gas output from the exhaust port 22 into the lean hydrocarbon inlet 301 to mix the lean hydrocarbon tail gas with external air.

[0020] When the device is in use, the storage tank 1 is used to temporarily store hazardous chemicals. By opening the feed valve 13, the liquid hazardous chemicals can enter the storage tank 1 through the feed inlet 11 for storage, and then the feed valve 13 is closed. When it is necessary to clean the storage tank 1, the discharge valve 16 is opened, and the hazardous chemicals are discharged from the storage tank 1 through the discharge outlet 15, and then the discharge valve 16 is closed. At this time, there are still residual toxic and harmful hazardous tail gases in the storage tank 1, and the tail gases mainly contain high-concentration volatile organic compounds (VOCs), carbon monoxide (CO) and a small amount of residual hydrocarbon substances.

[0021] At this time, the conveying device is started, and the driving mechanism 5 drives the two conveying mechanisms 6 to run simultaneously. In order to facilitate the distinction between the two conveying mechanisms 6, the two conveying mechanisms 6 are respectively defined as the first conveying component and the second conveying component. The driving mechanism 5 drives the first conveying component and the second conveying component to run simultaneously. The first conveying component extracts the residual tail gas in the storage tank 1, making the inside of the storage tank 1 form a negative pressure. After the tail gas is discharged from the gas extraction port 12, the extracted tail gas is conveyed to the inside of the cryogenic oil and gas treatment device 2 through the first conveying component from the separation inlet 21. The cryogenic oil and gas treatment device 2 conducts condensation and cooling treatment on the tail gas, so that the VOCs components in the tail gas are liquefied and separated from the CO gas and other hydrocarbon substances. The accumulated VOCs substances can be discharged from the cryogenic oil and gas treatment device 2 through the liquid discharge port 23 by opening the liquid discharge valve 24, while the CO and other hydrocarbon substances combine to form lean hydrocarbon gas, which is discharged from the exhaust port 22 and then introduced into the mixing device 3 through the lean hydrocarbon inlet 301.

[0022] At the same time, the second conveying component is running, drawing external air and conveying it to the mixing device 3 through the air inlet 302. Inside the mixing device 3, the external air is mixed with the hydrocarbon-lean gas to form a mixed gas, which is discharged from the mixing outlet 303 and enters the catalytic oxidation device 4 from the catalytic inlet 41. The catalytic oxidation device 4 of the present invention is a CO catalytic oxidation furnace, which has a built-in Pt-Pd / Al2O3 honeycomb catalyst layer and an operating temperature of 350°C-400°C. When the device is running, it can catalytically oxidize carbon monoxide into carbon dioxide, and the CO catalytic oxidation furnace is integrated with a regeneration module to achieve self-cleaning of the catalyst.

[0023] After the mixed gas composed of the lean hydrocarbon gas and the external air is catalytically oxidized into carbon dioxide, it is discharged through the catalytic outlet 42. At this time, the exhaust gas discharged from the catalytic outlet 42 has a relatively high temperature, while the temperature of the lean hydrocarbon gas discharged from the exhaust port 22 of the deep-cold oil and gas processing device 2 is reduced. By connecting the catalytic outlet 42 with the heat exchange inlet 304, the high-temperature gas generated after catalytic oxidation can enter the mixing device 3, and exchange heat with the lean hydrocarbon gas and the external air in the mixing device 3. On the one hand, the lean hydrocarbon gas and the external air can be heated to form a mixed gas with a relatively high temperature, which is passed into the catalytic oxidation device 4 to facilitate the catalytic oxidation of carbon monoxide gas in the mixed gas. On the other hand, after the heat exchange, the temperature of the exhaust gas can be reduced, so that the exhaust gas is discharged to the outside after cooling, thereby reducing environmental pollution and damage to the outside.

[0024] Therefore, after adopting the above-mentioned technology, the heat energy generated by catalytic oxidation can be fully utilized, and the exhaust gas is discharged into the mixing device 3 to exchange heat with the low-temperature hydrocarbon-lean gas and the external air, thereby increasing the temperature of the mixed gas and promoting the catalytic oxidation of carbon monoxide gas in the mixed gas. At the same time, the high-temperature exhaust gas can be cooled to reduce the white mist generated by the large temperature difference with the outside when it is discharged, and reduce the pollution harm to the environment, thereby achieving energy saving and environmental protection. In addition, in the present invention, a driving mechanism 5 can drive two conveying mechanisms 6 to operate synchronously, which are used to convey two different gases, one of which is the exhaust gas extracted from the storage tank 1, and the other is the external air. Compared with the prior art, the number of driving sources is reduced, the equipment cost is reduced, and the device is made more compact, the occupied space is reduced, and the increase in device cost and occupied space caused by the installation of two air pumps is avoided.

[0025] A further improvement is that the conveying mechanism 6 correspondingly connected to the air inlet 302 has a filter assembly 8 connected at its input end.

[0026] The filter assembly 8 can filter out dust and impurities in the external air to prevent these impurities from entering the equipment pipeline and affecting the normal operation of the device.

[0027] The specific structure of the filter assembly 8 is as follows:Figure 5 and Figure 6 As shown in Figure 6 , it includes a filter barrel 81 with an open top and fixed to the bottom surface through feet. An air inlet 811 is provided on the side wall of the filter barrel 81, and a waste discharge port 812 is provided at the bottom. An air inlet valve 813 and a waste discharge valve 814 are respectively connected to the air inlet 811 and the waste discharge port 812. A collection box 87 with an open top is provided directly below the waste discharge port 812. The top of the filter barrel 81 is detachably connected by a bolt 84 and a nut 85 connected by threads and is covered with a filter cover 82. An air outlet 821 is provided on the filter cover 82, and the air outlet 821 is communicated with a connecting hose 86. The connecting hose 86 is connected to the air inlet end of the first conveying assembly.

[0028] A filter element 83 is arranged in the filter barrel 81. Specifically, an inner convex ring 815 coaxial with the filter barrel 81 and located above the air inlet 811 is integrally connected to the circumferential inner wall of the filter barrel 81. The top of the filter element 83 is open, and the circumferential outer edge is hermetically attached to the circumferential inner wall of the inner convex ring 815. An outward turning edge 831 is provided on the circumferential outer edge of the top. A positioning pressing ring 822 is integrally connected below the filter cover 82. The circumferential outer edge of the positioning pressing ring 822 is hermetically connected to the circumferential inner wall of the filter barrel 81. The outward turning edge 831 is clamped between the inner convex ring 815 and the positioning pressing ring 822.

[0029] After adopting the above structure, through the bolt 84 and nut 85 connected by threads, it is convenient for the detachable connection of the filter barrel 81 and the filter cover 82, and it is convenient to regularly open the filter barrel 81 to clean and replace the filter element 83. During the assembly process, while fastening the filter cover 82 to the filter barrel 81 through the bolt 84 and nut 85, the positioning pressing ring 822 can ensure the precise docking of the filter cover 82 and the filter barrel 81. At the same time, the positioning pressing ring 822 presses the outward turning edge 831 against the inner convex ring 815 to fix the position of the filter element 83. When the filtering assembly 8 is in use, external dusty gas enters the filter barrel 81 through the air inlet 811. Dust particles and impurities in the air are filtered out by the filter element 83. After the clean air passes through the filter element 83, it is discharged from the air outlet 821 and enters the first conveying assembly through the connecting hose 86. After being used for a period of time, the waste discharge valve 814 connected to the waste discharge port 812 can be opened, so that the dust particles deposited at the bottom of the filter barrel 81 can fall into the collection box 87 below through the waste discharge port 812 of the ventilation pipe, and then the waste discharge valve 814 is closed to ensure a certain cleanliness inside the filter barrel 81 and avoid the filter element 83 being easily blocked due to too much dust particles in the filter barrel 81.

[0030] A further improvement is that each of the two conveying mechanisms 6 includes two facing conveying units 61. Each of the two conveying units 61 includes a cylinder 611 and a piston 612 that is hermetically connected to and slidably engaged with the inner wall of the cylinder 611 along the axial direction of the cylinder 611. An inlet 6111 and an outlet 6112 are provided on the cylinder 611. Two one-way valves 613 with opposite directions are connected to the inlet 6111 and the outlet 6112. The driving mechanism 5 drives the pistons 612 of the two conveying units 61 in the conveying mechanism 6 to move synchronously.

[0031] As Figure 7 and Figure 8 shown, the conveying device further includes a fixing frame 9. The fixing frame 9 is fixed directly above the mixing device 3. The fixing frame 9 is used to support the driving mechanism 5 and the two conveying mechanisms 6. The mixing device 3 is in the shape of a horizontal cuboid. The two conveying mechanisms 6 are distributed in the vertical direction. The first conveying assembly is located directly above the second conveying assembly. Both the first conveying assembly and the second conveying assembly include two facing conveying units 61. The distribution direction of the two conveying units 61 is parallel to the width direction of the mixing device 3.

[0032] The cylinders 611 of the two conveying units 61 are fixed to the fixing frame 9, and the length direction is parallel to the width direction of the mixing device 3. The piston 612 includes a piston plate that is hermetically fitted to the circumferential inner wall of the cylinder 611 and a piston shaft fixedly connected to the piston plate. The inlet 6111 and the outlet 6112 are both provided at the end of the cylinder 611 away from the other cylinder 611. A filter screen 614 is fixed to the other end of the cylinder 611. The piston shaft penetrates the filter screen 614 in a sealed manner. The driving mechanism 5 is fixedly connected to the ends of the piston shafts of the two conveying units 61 in the conveying mechanism 6.

[0033] Each of the two conveying mechanisms 6 also includes two three-way pipes 62. For the upper first conveying assembly, among the two three-way pipes 62, one three-way pipe 62 has one input end and two output ends at its three ends. This input end is communicated with the connecting hose 86, and the two output ends are respectively communicated with the conveying inlets 6111 of the two cylinders 611. The remaining one three-way pipe 62 has one output end and two input ends at its three ends. The two input ends are respectively communicated with the output outlets 6112 of the two cylinders 611, and the output end is communicated with the air inlet 302 of the mixing device 3. In this way, when the driving mechanism 5 drives the first conveying assembly to operate, the two pistons 6111 move synchronously. By using the one-way valve 613 to restrict the air flow direction, one of the three-way pipes 62 can introduce external air into one of the cylinders 611 through the conveying inlet 6111, and the other three-way pipe 62 can introduce the introduced external air into the mixing device 3 through the air inlet 302 from the conveying outlet 6112. In this way, the high-speed conveying of external air is achieved.

[0034] For the second conveying component below, among the two three-way pipes 62, one of the three-way pipes 62 has three ends, namely one input end and two output ends. The input end is communicated with the connected air extraction port 12, and the two output ends are respectively communicated with the conveying inlets 6111 of the two cylinder barrels 611. The remaining one three-way pipe 62 has three ends, namely one output end and two input ends. The two input ends are respectively communicated with the output outlets 6112 of the two cylinder barrels 611, and the output end is communicated with the separation inlet 21 of the cryogenic oil and gas treatment device 2. In this way, when the driving mechanism 5 drives the first conveying component to operate, the two pistons 6111 move synchronously. By using the one-way valve 613 to restrict the air flow direction, one of the three-way pipes 62 can extract the tail gas in the storage tank 1 from the air extraction port 12 and then introduce it into one of the cylinder barrels 611 through the conveying inlet 6111, while the other three-way pipe 62 can discharge the introduced tail gas from the conveying outlet 6112 and inject it into the cryogenic oil and gas treatment device 2 through the separation inlet 21. The VOCs substances in the tail gas are liquefied and separated by the cylinder cooling method to form lean hydrocarbon gas.

[0035] For the filter screen 614 connected to the end of the cylinder barrel 611 in the conveying unit 61, it can prevent external air from entering the inside of the cylinder barrel 611 and affecting the sealing performance between the piston plate and the cylinder barrel 611.

[0036] A further improvement is that the driving mechanism 5 includes a driving unit 51, a turntable 52, and two transmission units 53 arranged on both sides of the turntable 52. The driving unit 51 drives the turntable 52 to rotate around its own axis. The two transmission units 53 are respectively arranged on both sides of the turntable 52 and are respectively connected to the two conveying mechanisms 6 correspondingly. The two transmission units 53 include a convex shaft 531 arranged on the turntable 52 and having a distance from the axis of the turntable 52, and a moving frame 532 sleeved outside the convex shaft 531. The moving frame 532 is fixedly connected to the pistons 612 of the two conveying units 61 in the corresponding conveying mechanism 6. The moving directions of the two moving frames 532 are consistent with the distribution direction of the two conveying units 61 in the conveying mechanism 6.

[0037] More specifically, the turntable 52 is horizontally arranged. The two conveying mechanisms 6 are respectively arranged on the upper and lower sides of the turntable 52 and are respectively connected to the turntable 52 through the two transmission units 53. After the driving unit 51 drives the turntable 52 to rotate, the convex shaft 531 on the turntable 52 rotates in a fixed direction with the center line of the turntable 52 as the axis. The convex shaft 531 acts on the moving frame 532, and then drives the moving frame 532 to reciprocate along the width direction parallel to the mixing device 3, thereby driving the two pistons 612 in the conveying mechanism 6 to reciprocate, and further enabling the conveying mechanism 6 to drive the gas to flow, introducing external air into the mixing device 3, and pumping out the residual tail gas in the storage tank 1 and transporting it to the cryogenic oil and gas treatment device 2.

[0038] More specifically, in the present invention, the specific structure of the fixing frame 9 is as follows Figures 7 - 9 As shown, the fixing frame 9 includes a horizontal bottom plate 91, the bottom plate 91 is T-shaped, above one end of the bottom plate 91, a motor frame 92 is fixed, and the other two ends are distributed along the width direction of the mixing device 3 and a bracket 93 is fixed above them. The bracket 93 has two fixing through holes distributed in the vertical direction, and the outer circumference of the cylinder barrel 611 is fixedly connected to the inner wall of the circumference of the fixing through hole; at the adjacent ends of the two brackets 93, a cross frame 94 extending along the length direction of the mixing device 3 is fixed, and between the ends of the two cross frames 94, they are fixedly connected by a horizontal frame 95. The length direction of the frame 95 is parallel to the width direction of the mixing device 3. The frame 95 includes two cross bars 951 and two vertical bars 952. The two cross bars 951 and the two vertical bars 952 are connected end to end in sequence to form a rectangular frame. The length direction of the cross bar 951 is parallel to the width direction of the mixing device 3, and the length direction of the vertical bar 952 is the vertical direction. On both cross frames 94, a horizontal bearing frame 96 is fixedly connected.

[0039] The driving unit 51 includes a driving motor 511. The driving motor 511 is fixedly mounted upward above the motor frame 92, and the output end is coaxially fixedly connected with a driving gear 512. The outer circumference of the turntable 52 is annularly and arrayedly distributed with convex teeth, so that the turntable 52 and the convex teeth are combined to form a driven gear meshing with the driving gear 512. Two convex shafts 531 are respectively arranged above and below the turntable 52. A support bearing 521 is arranged below the turntable 52, and the lower convex shaft 531 is located inside the support bearing 521. The outer ring of the support bearing 521 is fixedly connected with the bearing frame 96, and the inner ring is fixedly connected with the turntable 52 coaxially.

[0040] After adopting the above structure, when the driving motor 511 is started, it drives the driving gear 512 to rotate, acting on the convex teeth outside the turntable 52. Under the support of the support bearing 521, the turntable 52 can rotate around its own axis.

[0041] As Figure 7 、 Figure 12 and Figure 13 shown, in the two transmission units 53, the length direction of the moving frame 532 is parallel to the length direction of the mixing device 3. At both ends of the moving frame 532, sliding sleeves 534 are fixed. The sliding sleeves 534 are sleeved on the cross bars 951 one by one and are slidably matched with the cross bars 951. On the side of the two sliding sleeves 534 facing away from the turntable 52, they are fixedly connected by a connecting bar 533. The connecting bar 533 is fixedly connected with the piston 612. In this way, it is ensured that the moving frame 532 moves smoothly along the width direction of the mixing device 3.

[0042] A further improvement is that an adjusting unit 54 is provided between one of the convex shafts 531 and the turntable 52 to adjust the distance between the axis of the convex shaft 531 and the axis of the turntable 52, and the other convex shaft 531 is fixedly connected to the turntable 52. A flow sensor 306 is connected to the lean hydrocarbon inlet 301.

[0043] Specifically, the top surface of the turntable 52 is connected to the convex shaft 531 through the adjusting unit 54. The adjusting unit 54 can adjust the distance between the axis of the convex shaft 531 and the axis of the turntable 52, thereby adjusting the reciprocating movement amplitude of the moving frame 532 above the turntable 52. The convex shaft 531 located below is fixed to the bottom surface of the turntable 52, so that the reciprocating movement amplitude of the lower moving frame 532 remains unchanged, and the reciprocating movement frequencies of the two moving frames 532 are the same. Therefore, on the above basis, the distance between the upper convex shaft 531 and the axis of the turntable 52 can be controlled by the adjusting unit 54 according to the flow data detected by the flow sensor 306. During specific operation, when the flow data detected by the flow sensor 306 is relatively large, it indicates that there is more lean hydrocarbon gas and less external gas in the mixed gas. At this time, the adjusting unit 54 controls the convex shaft 531 to approach the axis of the turntable 52 to reduce the movement amplitude of the upper moving frame 532 and reduce the amount of tail gas extracted during the operation of the first conveying component, ensuring that there is sufficient air in contact with the lean hydrocarbon gas and avoiding incomplete oxidation of carbon monoxide due to excessive lean hydrocarbon gas; conversely, when the flow data detected by the flow sensor 306 is relatively small, it indicates that there is less lean hydrocarbon gas and more external gas in the mixed gas. At this time, the adjusting unit 54 controls the convex shaft 531 to move away from the axis of the turntable 52 to increase the movement amplitude of the upper moving frame 532 and increase the amount of tail gas extracted during the operation of the first conveying component, ensuring that there is sufficient lean hydrocarbon gas in contact with the air. After forming the mixed gas, it can be introduced into the catalytic oxidation device 4 to achieve full oxidation of the lean hydrocarbon gas in the mixed gas, while also avoiding excessive external air and reducing the catalytic oxidation efficiency of carbon monoxide.

[0044] A further improvement is that the adjusting unit 54 includes an adjusting motor 541 provided on the convex shaft 531. The adjusting motor is drivingly connected to a lead screw 542. The lead screw 542 is threadedly connected to a nut sleeve 543. The convex shaft 531 corresponding to the adjusting unit 54 is fixed to the nut sleeve 543. A distance sensor 544 for detecting the position of the nut sleeve 543 is provided on the turntable 52.

[0045] Specifically, as Figure 13 and Figure 14As shown in the figure, the top surface of the turntable 52 is provided with a long strip-shaped groove, and the adjusting unit 54 is arranged inside the groove. The adjusting unit 54 further includes a support bushing 545. Both the adjusting motor 541 and the support bushing 545 are fixed in the groove. The screw sleeve 543 is slidably fitted in the groove. One end of the lead screw 542 away from the adjusting motor 541 rotates inside the support bushing 545 around the axis of the lead screw 542. The convex shaft 531 is fixed above the screw sleeve 543, and the distance sensor 544 is fixed on the adjusting motor 541 and faces the screw sleeve 543.

[0046] After adopting the above structure, the distance between the distance sensor 544 and the screw sleeve 543 is detected to determine the distance between the upper convex shaft 531 and the axis of the turntable 52. When the distance needs to be adjusted, the adjusting motor 541 is started to drive the lead screw 542 to rotate around its own axis under the action of the support bushing 545. The lead screw 542 acts on the screw sleeve 543 through the thread, so that the screw sleeve 543 slides along the chute, and then drives the convex shaft 531 to move, realizing the adjustment of the distance between the axis of the convex shaft 531 and the axis of the turntable 52, and thus being able to adjust the reciprocating movement amplitude of the upper moving frame 532.

[0047] A further improvement is that the mixing device 3 has a preheating chamber 307 communicated with the air inlet 302 and a heat exchange chamber 308 communicated with the heat exchange outlet 305. A preheating coil 31 is arranged in the preheating chamber 307. The input end of the preheating coil 31 is the preheating inlet 6111, and the output end is communicated with the heat exchange chamber 308 through a heat insulation pipe 351. Inside the heat exchange chamber 308, an outer pipe 32 is arranged. Both ends of the outer pipe 32 are respectively communicated with the heat insulation pipe 351 and the heat exchange outlet 305. An inner pipe 33 penetrates through the inside of the outer pipe 32. Both ends of the inner pipe 33 are respectively communicated with the lean hydrocarbon inlet 301 and the preheating chamber 307; the outer pipe 32 is densely arranged in the heat exchange chamber 308.

[0048] After adopting the above structure, the high-temperature waste gas (mainly carbon dioxide generated after catalytic oxidation treatment of carbon monoxide) generated by the catalytic oxidation device 4 enters the preheating coil 31 in the preheating chamber 307 through the heat exchange inlet 304. While the high-temperature carbon dioxide flows in the preheating coil 31, it exchanges heat with the mixed air composed of the lean hydrocarbon gas and the external air in the preheating chamber 307 through the wall of the preheating coil 31, increasing the temperature of the mixed air, so that the mixed air can enter the catalytic oxidation device 4 at a higher temperature to promote the contact oxidation of carbon monoxide gas in the mixed gas with the external air and improve the carbon monoxide conversion rate.

[0049] After preheating the mixed gas with high-temperature waste gas, the high-temperature waste gas still has a certain amount of heat, and its temperature is significantly higher than the outside air temperature, especially the temperature of the lean hydrocarbon gas discharged from the exhaust port 22 of the cryogenic oil and gas treatment device 2. Considering the above factors, the high-temperature waste gas after the first heat exchange is introduced into the heat exchange chamber 308. While the high-temperature waste gas flows inside the outer pipe 32, the lean hydrocarbon gas after separation, with a lower temperature, enters the heat exchange chamber 308 from the lean hydrocarbon inlet 301 and flows inside the inner pipe 33 inside the outer pipe 32. When the high-temperature waste gas after the first heat exchange passes through the inner wall of the inner pipe 33, it exchanges heat with the low-temperature lean hydrocarbon gas inside the inner pipe 33. After the high-temperature waste gas cools down, it is discharged from the heat exchange outlet 305 of the mixing device 3. After the low-temperature lean hydrocarbon gas exchanges heat, its temperature rises to form normal-temperature lean hydrocarbon gas. The inner pipe 33 corresponds to the outer pipe 32 one by one, and the outer pipes 32 are densely arranged in the heat exchange chamber 308, thus increasing the heat exchange contact area. At the same time, by performing two heat exchanges on the high-temperature waste gas, the heat energy of the high-temperature waste gas can be fully utilized, realizing energy conservation and environmental protection, enabling it to significantly increase the temperature of the lean hydrocarbon gas and the external air, thereby promoting the conversion rate of carbon monoxide in the mixed air and reducing the content of carbon monoxide in the final waste gas, reducing the harm to the surrounding environment.

[0050] As Figure 15 and Figure 16 shown, a horizontal support plate 34 is fixed below the mixing device 3, and support feet 341 are provided on the bottom surface of the support plate 34 to support the mixing device 3.

[0051] More specifically, as Figures 15 - 21 shown, the mixing device 3 includes a heat exchange shell 37, a partition plate 38, and a mixing box 36 connected in sequence. All three are fixed above the support plate 34. The partition plate 38 is arranged vertically. The sides of the mixing box 36 and the heat exchange shell 37 facing the partition plate 38 are both open. The mixing box 36 and the partition plate 38 enclose a preheating chamber 307, and the heat exchange shell 37 and the partition plate 38 enclose a heat exchange chamber 308.

[0052] Among them, the mixing box 36 includes an air inlet hood 363 fixed to the partition plate 38 and a mixing hood 361 fixed to the side of the air inlet hood 363 away from the partition plate 38. The mixing outlet 303 is arranged on the side of the mixing hood 361 facing away from the partition plate 38. A flow dividing plate 362 is fixed in the mixing hood 361. The circumferential inner wall of the flow dividing plate 362 is fixedly connected to the circumferential outer edge of the mixing hood 361. The flow dividing plate 362 is densely provided with flow dividing through holes to ensure uniform distribution of the mixed air flow on the air inlet side of the mixing outlet 303. The preheating coil 31 is fixed between the mixing box 36 and the air inlet hood 363. One end of it is fixedly sealed and penetrates through the inner side wall of the mixing hood 361 and is communicated with the outlet of the catalytic outlet 42, which is convenient for the high-temperature waste gas generated by the catalytic oxidation device 4 to enter the preheating coil 31 through the catalytic outlet 42. An insulation outlet 3611 is opened on the same side of the mixing hood 361. The inner wall of the insulation outlet 3611 is fixedly communicated with the other end of the preheating coil 31. The outer wall of the insulation outlet 3611 is communicated with the heat exchange chamber 308 through an insulation pipe 351.

[0053] The air inlet 302 is arranged at the top of the air inlet hood 363 and is fixedly communicated with an air inlet pipe 3021. The air inlet pipe 3021 is fixedly communicated with the output end of the three-way pipe 62 on the air outlet side in the first conveying assembly, which is convenient for the first conveying assembly to introduce external air into the air inlet hood 363. A flow guiding through hole is arranged on the side of the air inlet hood 363 facing the partition plate 38. The inner pipe 33 is fixedly sealed and penetrates through the partition plate 38 and through the flow guiding through hole. There is a gap between the circumferential outer edge of the inner pipe 33 and the circumferential inner wall of the flow guiding through hole, which is convenient for the external air entering the inner side of the air inlet hood 363 from the air inlet 302 to enter the inner side of the mixing hood 361 through the above gap. And a flow guiding cover 364 facing the end of the inner pipe 33 is fixed at one end of the inner pipe 33 close to the partition plate 38. In this way, when the lean hydrocarbon gas flows out of the inner pipe 33, it is guided by the flow guiding cover 364 to contact the external air passing through the above gap, so as to ensure the full and uniform mixing of the lean hydrocarbon gas and the external air.

[0054] The heat exchange shell 37 includes a shell cover 372, a shell hood 371, a closed channel 375, and an exhaust hood 376 that are connected in sequence. The shell cover 372 is fixedly covered on the shell hood 371. An opening is provided on the side wall of the shell hood 371, and the opening is fixedly communicated with the end of the heat insulation pipe 351. A heat insulation cover 35 is provided outside the heat insulation pipe 351. The heat insulation cover 35 is fixedly communicated with the shell hood 371, the closed channel 375, the exhaust hood 376, the partition plate 38, the air inlet cover 363, and the mixing cover 361. In this way, after the high-temperature waste gas passing through the preheating coil 31 undergoes primary heat exchange, it can enter the heat exchange cavity 308 through the heat insulation pipe 351. The heat insulation cover 35 can effectively reduce the diffusion of heat, ensuring that the waste gas still has a relatively high temperature after passing through the heat insulation pipe 351 and can heat the low-temperature lean hydrocarbon gas. A heat insulation inlet 3711 is provided on the shell hood 371, and the heat insulation inlet 3711 is fixedly communicated with the end of the heat insulation pipe 351 away from the mixing cover 361.

[0055] An inner shell hood 373 is fixedly provided inside the shell hood 371, and their open directions are the same. An inner shell cover 374 is fixedly covered on the open side of the inner shell hood 373. The lean hydrocarbon inlet 301 is opened on the inner shell cover 374 and a lean hydrocarbon inlet pipe that extends outward and penetrates the shell cover 372 in a sealed manner is provided; both the outer pipe 32 and the inner pipe 33 extend along the length direction parallel to the mixing device 3. One end of the outer pipe 32 is fixed on the shell hood 371 and communicated with the inner cavity of the shell hood 371, and the other end is fixedly sealed and penetrates the exhaust hood 376 and has a gap with the partition plate 38. The outer pipe 32 is located inside the closed channel 375; one end of the inner pipe 33 is fixed on the inner shell hood 373 and fixedly communicated with the inner cavity of the inner shell hood 373. The inner pipe 33 penetrates the inside of the outer pipe 32 and extends into the mixing cover 361; the heat exchange outlet 305 is provided inside the exhaust hood 376 and a vertical exhaust pipe 3051 extends downward. The outer pipe 32 and the inner pipe 33 are both distributed in a rectangular array inside the closed channel 375.

[0056] After adopting the above structure, the closed channel 375 can ensure that the outer pipe 32 is in a closed environment, reducing the heat diffusion of the high-temperature waste gas to the outside when passing through the outer pipe 32. When using the high-temperature waste gas for secondary heat exchange, the high-temperature waste gas enters the inside of the shell hood 371 through the heat insulation pipe 351, and through the annular gap between the inner wall of the outer pipe 32 and the outer wall of the inner pipe 33, after exchanging heat with the lean hydrocarbon gas in the inner pipe 33 by the side wall of the inner pipe 33, it enters the exhaust hood 376, is blocked by the partition plate 38, and then is discharged through the heat exchange outlet 305; while the low-temperature lean hydrocarbon gas enters the inner shell hood 373 through the lean hydrocarbon inlet 301 and flows through the inner pipe 33. During the flow through the inner pipe 33, it absorbs the heat of the high-temperature waste gas through the side wall of the inner pipe 33, so that its own temperature increases, and then it flows out from the end of the inner pipe 33 away from the inner shell hood 373 and enters the mixing cover 361 to contact the external air.

[0057] A further improvement is that a waste liquid pool 7 is provided at the bottom of the mixing device 3, and the bottom of the waste gas pipe 3051 is disposed in the waste liquid pool 7.

[0058] Specifically, the top of the waste liquid pool 7 is open, and it is located directly below the mixing device 3. The bottom of the waste gas pipe 3051 is located directly below the waste liquid pool 7. A waste discharge pipe 71 is provided at the bottom of the waste liquid pool 7, and the waste discharge pipe 71 is connected with a waste liquid valve 72. The waste liquid pool 7 is used to store alkaline liquid, such as sodium hydroxide solution or calcium hydroxide solution. After adopting the above structure, after the waste gas is heat-exchanged, it is introduced into the waste liquid pool 7, and the carbon dioxide in the waste gas reacts chemically with the alkaline liquid in the waste liquid pool 7, thereby achieving the effect of absorbing carbon dioxide and reducing the carbon dioxide emission. After using for a period of time, the waste liquid valve 72 is opened to discharge the waste liquid through the waste discharge pipe 71, and then the waste liquid valve 72 is closed, and alkaline liquid is replenished into the waste liquid pool 7.

[0059] A further improvement is that a support inner frame 73 is fixed on the circumferential inner wall of the waste liquid pool 7. An outer frame 74 is provided on the support inner frame 73. The circumferential inner wall of the outer frame 74 is connected with a sponge plate 75. The waste gas pipe 3051 is sealed and penetrates through the sponge plate 75, and the outer edge of the outer frame 74 is hermetically attached to the circumferential inner wall of the waste liquid pool 7.

[0060] The waste gas containing a large amount of carbon dioxide is discharged into the waste liquid pool 7 through the waste gas pipe 3051. While forming bubbles and floating in the waste liquid pool 7, the sponge plate 75 connected by the outer frame 74 can block above the bubbles formed by the waste gas, increasing the reaction contact time between the waste gas and the alkaline liquid, ensuring the full progress of the reaction, and thus further reducing the carbon dioxide emission.

[0061] The present invention also provides a tail gas treatment method based on negative pressure suction, including the following steps: S100, discharging materials: discharging the liquid hazardous chemicals in the storage tank 1; S200, air extraction: introducing the tail gas in the storage tank 1 into the cryogenic oil and gas treatment device 2 to discharge the lean hydrocarbon gas; S300, mixing: introducing external air and lean hydrocarbon gas into the mixing device 3 for mixing to discharge the mixed gas; S400, catalytic oxidation: catalytically oxidizing the mixed gas to discharge the high-temperature waste gas; S500, diversion: introducing the waste gas into the mixing device 3 to heat-exchange the external air and lean hydrocarbon gas and then discharging it to the outside; The conveying mechanism 6 used for tail gas conveying in step S200 and the conveying mechanism 6 used for external air conveying in step 300 are both driven by the same driving mechanism 5 to operate.

[0062] Compared with the prior art, in the exhaust gas treatment method of the present invention, the residual exhaust gas in the storage tank 1 is extracted and cooled by the cryogenic oil and gas treatment device 2 to liquefy the VOCs components in the exhaust gas, forming lean hydrocarbon gas. After mixing the lean hydrocarbon gas with external air, the mixed gas is introduced into the catalytic oxidation device 4 for catalytic oxidation treatment, so that carbon monoxide is catalytically oxidized into carbon dioxide and then discharged. The discharged waste gas has a relatively high temperature. Therefore, the high-temperature waste gas is introduced into the mixing device 3 to exchange heat with the low-temperature lean hydrocarbon gas and external air, so that the mixed gas has a relatively high temperature before catalytic oxidation, thereby promoting the catalytic oxidation and improving the conversion rate of carbon monoxide. Moreover, the conveying mechanism 6 for conveying the exhaust gas and external air is driven by the same driving mechanism 5, which can simplify the structure, ensure the simultaneous conveyance of external air and exhaust gas, and ensure the structural compactness of the equipment, reducing the space occupied by the equipment.

[0063] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the technical principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. An exhaust gas treatment device based on negative pressure suction, characterized in that Comprising: A storage tank having a feed inlet, a discharge outlet, and an air extraction port, wherein the feed inlet, the discharge outlet, and the air extraction port are respectively connected with a feed valve, a discharge valve, and an air extraction valve; A cryogenic oil and gas treatment device having a separation inlet, an exhaust port, and a liquid discharge port, and the liquid discharge port is connected with a liquid discharge valve; A mixing device having a lean hydrocarbon inlet, an air inlet, a mixing outlet, a heat exchange inlet, and a heat exchange outlet, and the lean hydrocarbon inlet is communicated with the exhaust port; A catalytic oxidation device having a catalytic inlet and a catalytic outlet, and the catalytic outlet is communicated with the heat exchange inlet; A conveying device comprising a driving mechanism and two conveying mechanisms. The driving mechanism is used to provide power to the two conveying mechanisms, so that while one conveying mechanism introduces external air into the air inlet, the other conveying mechanism inputs the lean hydrocarbon gas output from the exhaust port into the lean hydrocarbon inlet to mix the lean hydrocarbon tail gas with the external air.

2. The exhaust gas treatment device based on negative pressure suction according to claim 1, wherein: Both of the two conveying mechanisms include two opposed conveying units. Each of the two conveying units includes a cylinder barrel and a piston that is hermetically connected to and slidably matched with the inner wall of the cylinder barrel along the axial direction of the cylinder barrel. An inlet and an outlet are provided on the cylinder barrel, and two one-way valves with opposite directions are connected to the inlet and the outlet. The driving mechanism drives the pistons of the two conveying units in the conveying mechanism to move synchronously.

3. The exhaust gas treatment device based on negative pressure suction according to claim 2, wherein: The driving mechanism includes a driving unit, a turntable, and two transmission units arranged on both sides of the turntable. The driving unit drives the turntable to rotate around its own axis. The two transmission units are respectively arranged on both sides of the turntable and are correspondingly connected to the two conveying mechanisms. The two transmission units include a convex shaft arranged on the turntable and having a distance from the axis of the turntable and a moving frame sleeved outside the convex shaft. The moving frame is fixedly connected to the pistons of the two conveying units in the corresponding conveying mechanism, and the moving directions of the two moving frames are consistent with the distribution direction of the two conveying units in the conveying mechanism.

4. The exhaust gas treatment device based on negative pressure suction according to claim 3, characterized in that: An adjusting unit is arranged between one of the convex shafts and the turntable to adjust the distance between the convex shaft and the axis of the turntable. The other convex shaft is fixedly connected to the turntable, and a flow sensor is connected to the lean hydrocarbon inlet.

5. The tail gas treatment device based on negative pressure suction according to claim 4, wherein: The adjusting unit includes an adjusting motor arranged on the convex shaft. The adjusting motor is drivingly connected with a lead screw. The lead screw is threadedly connected with a nut sleeve. The convex shaft corresponding to the adjusting unit is fixed on the nut sleeve. A distance sensor for detecting the position of the nut sleeve is arranged on the turntable.

6. The tail gas treatment device based on negative pressure suction according to claim 1, wherein: The mixing device has a preheating chamber communicated with the air inlet and a heat exchange chamber communicated with the heat exchange outlet. A preheating coil is arranged in the preheating chamber. The input end of the preheating coil is the preheating inlet, and the output end is communicated with the heat exchange chamber through a heat-insulating pipe. In the heat exchange chamber, an outer pipe is arranged. Both ends of the outer pipe are respectively communicated with the heat-insulating pipe and the heat exchange outlet. An inner pipe penetrates through the inside of the outer pipe. Both ends of the inner pipe are respectively communicated with the lean hydrocarbon inlet and the preheating chamber.

7. The exhaust gas treatment device based on negative pressure suction according to claim 6, characterized in that: The outer pipes are densely arranged in the heat exchange chamber.

8. The tail gas treatment device based on negative pressure suction according to any one of claims 1-7, characterized in that: The heat exchange outlet is arranged at the bottom of the mixing device and is connected with an exhaust pipe extending downward. A waste liquid pool is arranged at the bottom of the mixing device, and the bottom of the exhaust pipe is arranged in the waste liquid pool.

9. The exhaust gas treatment device based on negative pressure suction according to any one of claims 1-7, characterized in that: The conveying mechanism corresponding to the air inlet is connected with a filtering component at its input end.

10. A tail gas treatment method based on negative pressure suction, characterized in that, It includes the following steps: S100, discharging: Discharge the liquid hazardous chemicals in the storage tank. S200, air extraction: Feed the tail gas in the storage tank into the cryogenic oil and gas treatment device to discharge the lean hydrocarbon gas. S300, mixing: Feed the external air and the lean hydrocarbon gas into the mixing device for mixing and discharge the mixed gas. S400, catalytic oxidation: Catalytically oxidize the mixed gas and discharge the high-temperature waste gas. S500, drainage: Feed the waste gas into the mixing device to exchange heat with the external air and the lean hydrocarbon gas and then discharge it to the outside. The conveying mechanism used for tail gas conveying in step S200 and the conveying mechanism used for external air conveying in step 300 are both driven by the same driving mechanism.

Images