A hydrochloric acid methanol tail gas absorption device for nicarbazine production

Abstract

The present invention belongs to the technical field of gas absorption and separation, and specifically relates to a hydrochloric acid methanol tail gas absorption device for nicarbazine production. The device comprises a shell, an absorption pipe, and an upper tube plate and a lower tube plate arranged in the shell. The shell is provided with a liquid inlet cavity and a liquid outlet cavity. The upper end of the absorption pipe is fixed on the upper tube plate and passes through the liquid inlet cavity, and the lower end of the absorption pipe is fixed on the lower tube plate. The device also comprises an overflow pipe and a detection and adjustment device. The overflow pipe is slidably sleeved on the upper end of the absorption pipe, and an overflow port is provided on the side of the overflow pipe. The detection and adjustment device comprises an upper mounting seat, a lower mounting seat, a fixed shaft, a collecting tube, an elastic support member, and a target rod fixed on the collecting tube and extending up and down. The collecting tube is located at the center of the absorption tube. A displacement sensor and an overflow pipe telescopic member are provided on the upper mounting seat. The displacement sensor is used to detect the displacement of the target rod. The overflow pipe telescopic member is connected to the overflow pipe and is used to drive the overflow pipe to rise and fall.

Description

Technical Field

[0001] The invention belongs to the technical field of gas absorption and separation, and particularly relates to a hydrochloric acid methanol tail gas absorption device for nicarbazine production. Background Art

[0002] During the production of nicarbazine, particularly during steps involving hydrochloric acid and methanol as reaction media, off-gases containing volatile organic compounds (VOCs) and acidic gases are generated. These off-gases not only pollute the environment but can also pose health risks to operators. Therefore, effective treatment of these off-gases is crucial for ensuring the sustainability and regulatory compliance of the production process. Falling film reactors, due to their high efficiency and energy-saving properties, have been widely used and developed for treating off-gases containing VOCs and acidic gases.

[0003] For example, patent publication number CN219922525U discloses a multi-stage falling film absorber, which includes an absorber head, a cooling absorption section, and a gas-liquid separation section. The absorber head is connected to a liquid inlet, and the cooling absorption section is equipped with several absorption tubes. The absorber head is equipped with a zigzag overflow distributor connected to each absorption tube. During use, absorption liquid enters the absorber head through the liquid inlet. When the absorption liquid in the absorber head is high, it overflows into the absorption tube through the zigzag overflow distributor and flows downward along the inner wall of the absorption tube, forming a liquid film. Exhaust gas flows in the absorption tube, where the absorption liquid and exhaust gas merge and absorb harmful substances in the exhaust gas.

[0004] In the prior art, the absorption liquid in the absorber head flows into a zigzag overflow distributor via overflow, thereby improving the uniformity of the absorption liquid flow rate within each absorber tube. However, in actual use, it was found that due to factors such as liquid inlet disturbance and the arrangement of the zigzag overflow distributor, the liquid level in the absorber head was not level, resulting in uneven flow rates within each absorber tube. Some absorber tubes had higher flow rates, resulting in thicker liquid films, causing some liquid to detach from the inner walls of the absorber tubes, resulting in flooding and lower gas-liquid reaction efficiency. Other absorber tubes had lower flow rates, resulting in unstable liquid films and dry wall phenomena, which also led to lower gas-liquid reaction efficiency. Summary of the Invention

[0005] The present invention provides a hydrochloric acid methanol tail gas absorption device for nicarbazine production, so as to solve the technical problem in the prior art that the gas-liquid reaction efficiency is low due to uneven flow distribution in an absorption pipe.

[0006] To solve the above problems, the present invention provides a hydrochloric acid methanol tail gas absorption device for nicarbazine production, which adopts the following technical solution: a hydrochloric acid methanol tail gas absorption device for nicarbazine production, comprising a shell, an absorption pipe, and an upper tube sheet and a lower tube sheet disposed within the shell, wherein the shell has a liquid inlet cavity located above the upper tube sheet and a liquid outlet cavity located below the lower tube sheet, the upper end of the absorption pipe is fixed to the upper tube sheet and passes through the liquid inlet cavity, and the lower end of the absorption pipe is fixed to the lower tube sheet; the hydrochloric acid methanol tail gas absorption device for nicarbazine production also includes an overflow pipe and a detection and adjustment device, the overflow pipe being slidably mounted on the upper end of the absorption pipe in the up-down direction, and an overflow port being provided on the side of the overflow pipe;

[0007] The detection and adjustment device includes an upper mounting seat located in the liquid inlet chamber, a lower mounting seat located in the liquid outlet chamber, a fixed shaft, a collecting cylinder slidably assembled on the fixed shaft, and an elastic support member fixed on the fixed shaft and supporting the collecting cylinder upward. It also includes a target rod fixed on the collecting cylinder and extending up and down. The fixed shaft passes through the absorption tube up and down, the upper end of the fixed shaft is fixed on the upper mounting seat, and the lower end is fixed on the lower mounting seat. The collecting cylinder is located at the center of the absorption tube and is used to collect liquid. A displacement sensor and an overflow pipe telescopic member are provided on the upper mounting seat. The displacement sensor is used to detect the displacement of the target rod. The overflow pipe telescopic member is connected to the overflow pipe and is used to drive the overflow pipe to rise and fall.

[0008] During use, if the flow rate of the liquid in the absorption tube is large, part of the liquid will fall into the collection tube. The collection tube overcomes the action of the elastic support and moves downward, and the target rod moves downward accordingly. The displacement sensor detects the displacement of the target rod. When the displacement exceeds the set value, the overflow tube telescopic member drives the overflow tube to rise, and the overflow port rises, reducing the amount of liquid entering the overflow tube. When the total flow rate remains unchanged, the liquid flow rate in other overflow tubes can be increased to balance the liquid flow rate in each absorption tube. In the present invention, by setting a fixed shaft and a collection tube in the absorption tube, the liquid that has separated from the inner wall of the absorption tube can be collected, thereby achieving the purpose of balancing the liquid flow rate in each absorption tube. Moreover, since the liquid film is formed on the inner wall of the absorption tube, the gas and liquid exchange at the liquid film. The fixed shaft and the collection tube are set at the center of the absorption tube, and the gas flows through the annular space between the fixed shaft and the absorption tube and the annular space between the collection tube and the absorption tube, avoiding the gas from flowing in the center of the absorption tube and forcing the gas to flow to the liquid film, thereby improving the reaction efficiency.

[0009] Preferably, the fixed shaft includes a hollow shaft at the top and a solid shaft at the bottom. An eccentric guide block is provided at the top of the solid shaft. The guide block is fixedly connected to the hollow shaft. The guide block passes through the collecting tube up and down. The target rod is fixed at the center position of the bottom of the collecting tube, and the target rod passes upward from the hollow shaft.

[0010] Preferably, the top of the target rod is adapted to penetrate into the upper mounting seat.

[0011] Preferably, the hydrochloric acid methanol tail gas absorption equipment for nicarbazine production includes an exhaust pipe fixed to the top of the shell, the upper mounting seat includes a box body with an opening facing downward and a sealing plate separately fixed to the opening of the box body, and the displacement sensor and the overflow pipe telescopic member are located in the space enclosed by the box body and the sealing plate.

[0012] The displacement sensor and the overflow pipe expansion member are located in the enclosed space, which separates the gas from the displacement sensor and the overflow pipe expansion member, thereby preventing acidic substances in the gas from corroding and damaging the displacement sensor and the overflow pipe expansion member.

[0013] Preferably, a top cover is provided on the top of the overflow pipe, and a connecting ring is provided on the top cover. The connecting ring is relatively rotatable in the circumferential direction and relatively fixedly assembled on the top cover in the vertical direction, and the overflow pipe telescopic member is connected to the connecting ring;

[0014] A first sliding protrusion is provided on the inner wall of the overflow pipe, and a first spiral groove is provided on the outer wall of the absorption pipe. The first sliding protrusion is slidably assembled in the first spiral groove. When the overflow pipe moves up and down, it can rotate under the action of the first spiral groove and the first sliding protrusion.

[0015] The overflow pipe can be rotated while being raised and lowered, which can change the direction of the overflow port; when the overflow pipes are arranged in a straight line, the direction of the overflow port can be changed to adjust the flow rate in the overflow pipe; and the target rod is located at the center of the overflow pipe, and the rotation of the overflow pipe will not affect the detection of the target rod by the displacement sensor.

[0016] Preferably, the top cover is provided with an annular groove, and the overflow pipe is connected and rotatably assembled around its axis in the annular groove.

[0017] Preferably, the cleaning device further comprises a cleaning rod and a driving component, wherein the upper and lower ends of the fixed shaft are provided with rotating rings, the rotating rings are relatively rotated in the circumferential direction and relatively fixedly assembled on the fixed shaft in the vertical direction, the upper and lower ends of the cleaning rod are hinged to the rotating rings through a connecting rod, the outer side of the cleaning rod has a rubber layer, and the side of the cleaning rod facing the fixed shaft is provided with a first wedge;

[0018] The driving component includes a driving tube that is slidably mounted on the outside of the fixed shaft and a second wedge block fixed on the outside of the driving tube. When the driving tube moves upward, the second wedge block pushes the first wedge block upward, and the cleaning rod moves upward while translating toward the inner wall of the absorption tube. The driving tube is provided with a cleaning rod through-hole for the cleaning rod to pass through. The cleaning rod can move horizontally in the cleaning rod through-hole. A second spiral groove is provided on the outer wall of the fixed shaft, and a second sliding protrusion that is slidably assembled in the second spiral groove is provided on the inner wall of the driving tube.

[0019] The inner wall of the absorption tube will become clogged with debris after prolonged use, affecting the stability of the liquid film and requiring cleaning. During cleaning, the drive tube moves upward, and the second and first wedges cooperate to move the cleaning rod upward and outward. The cleaning rod adheres to the inner wall of the absorption tube. As the drive tube moves upward, it rotates, driving the cleaning rod to rotate and clean the inner wall of the absorption tube.

[0020] Preferably, a drain outlet is provided on one side of the collecting cylinder, and the cleaning rod is used to close the drain outlet. The cleaning rod is separated from the drain outlet after being translated toward the absorption tube.

[0021] Preferably, the bottom inner side of the absorption tube has a reduced diameter section, the driving tube includes a tube body and an umbrella-shaped flow guide provided on the tube body, and the cleaning rod is provided with a through hole on the umbrella-shaped flow guide;

[0022] The top and bottom of the umbrella-shaped flow guide are both provided with inclined surfaces for guiding the liquid and gas toward the inner wall of the absorption tube. The umbrella-shaped flow guide can close the reduced diameter section when moving upward with the tube body.

[0023] When uncleaned, the umbrella-shaped guide's inclined surface guides gas flow toward the inner wall of the absorber tube, allowing the gas and liquid to react and absorb at the liquid film. When clean, the umbrella-shaped guide seals the reduced diameter section, interrupting the flow of liquid and causing it to gather at the guide, filling the absorber tube with liquid and improving cleaning efficiency. When uncleaned, the reduced diameter section can cause liquid in the absorber tube to gather. If the liquid film above the reduced diameter section is incomplete, it can be reformed by the liquid-gathering effect of the reduced diameter section.

[0024] Preferably, the cleaning device includes a support plate located above the lower mounting seat, and the driving tubes in each absorption tube are fixed on the support plate. The cleaning device also includes a support plate telescopic member located below the lower mounting seat and connected to the support plate.

[0025] The beneficial effect is as follows: when in use, if the flow rate of the liquid in the absorption tube is large, part of the liquid will fall into the collection tube, and the collection tube will overcome the action of the elastic support and move downward, and the target rod will move downward accordingly, and the displacement sensor will detect the displacement of the target rod. When the displacement exceeds the set value, the overflow tube telescopic member drives the overflow tube to rise, and the overflow port rises, reducing the amount of liquid entering the overflow tube; when the total flow rate remains unchanged, the liquid flow rate in other overflow tubes can be increased, thereby balancing the liquid flow rate in each absorption tube. In the present invention, by arranging a fixed shaft and a collection tube in the absorption tube, the liquid that has separated from the inner wall of the absorption tube can be collected, thereby achieving the purpose of balancing the liquid flow rate in each absorption tube; moreover, since the liquid film is formed on the inner wall of the absorption tube, the gas and liquid exchange at the liquid film. The fixed shaft and the collection tube are arranged at the center of the absorption tube, and the gas flows through the annular space between the fixed shaft and the absorption tube and the annular space between the collection tube and the absorption tube, avoiding the gas from flowing at the center of the absorption tube and forcing the gas to flow to the liquid film, thereby improving the reaction efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is the main view of the hydrochloric acid methanol tail gas absorption equipment used in the production of nicarbazine;

[0027] Figure 2 This is a top view of the hydrochloric acid methanol tail gas absorption equipment used in the production of nicarbazine;

[0028] Figure 3 for Figure 2 Cross-sectional view of section AA (showing only one set of absorber tubes and internal structure);

[0029] Figure 4 for Figure 3 Enlarged view of point A in the middle;

[0030] Figure 5 for Figure 3 Enlarged view of point B in the middle;

[0031] Figure 6 for Figure 3 Enlarged view of point C in the middle;

[0032] Figure 7 for Figure 3 Enlarged view of point D in the middle;

[0033] Figure 8 for Figure 3 Enlarged view of point E in the middle;

[0034] Figure 9 for Figure 3 Enlarged view of point F in the middle;

[0035] Figure 10The hydrochloric acid methanol tail gas absorption equipment for nicarbazine production after removing the gas outlet pipe, liquid inlet cylinder, and cooling cylinder (only three sets of absorption tubes are shown);

[0036] Figure 11 for Figure 10 Enlarged view of point G in the middle;

[0037] Figure 12 The hydrochloric acid methanol tail gas absorption equipment for nicarbazine production after removing the gas outlet pipe, liquid inlet cylinder, cooling cylinder, upper tube plate, and lower tube plate (only the structure of three groups of absorption pipes is shown, one group does not show the absorption pipe, overflow pipe and drive pipe, and one group does not show the absorption pipe);

[0038] Figure 13 for Figure 12 Enlarged view of point H in the middle;

[0039] Figure 14 for Figure 12 The enlarged view of point I in the middle;

[0040] Figure 15 It is a structural diagram of the top of the absorption tube;

[0041] Figure 16 This is a structural diagram of the overflow pipe from the first perspective;

[0042] Figure 17 This is a structural diagram of the overflow pipe from a second perspective;

[0043] Figure 18 It is a structural diagram of the intersection of the hollow shaft and the solid shaft in the fixed shaft;

[0044] Figure 19 It is a structural diagram of the bottom of the fixed shaft;

[0045] Figure 20 It is a structural diagram of the collecting tube and target rod;

[0046] Figure 21 Schematic diagram of the structure of the driving tube;

[0047] Figure 22 Schematic diagram of the structure of the cleaning rod.

[0048] Description of reference numerals:

[0049] 11. Shell; 12. Liquid inlet pipe; 13. Liquid outlet pipe; 14. Air inlet pipe; 15. Air outlet pipe; 16. Upper tube sheet; 17. Lower tube sheet; 18. Coolant inlet pipe; 19. Coolant outlet pipe; 110. Absorption tube; 111. Overflow pipe; 112. Liquid inlet cylinder; 113. Cooling cylinder; 114. Liquid outlet cylinder; 115. Inner chamfer; 116. Reduced diameter section; 117. First spiral groove; 118. Overflow port; 119. Top cover; 120. Annular groove; 121. First sliding protrusion;

[0050] 21. Upper mounting seat; 22. Lower mounting seat; 23. Fixed shaft; 24. Collecting cylinder; 25. Target rod; 26. Displacement sensor; 27. Overflow pipe expansion member; 28. Box body; 29. Closing plate; 210. Connecting block; 211. Mounting block; 212. Hollow shaft; 213. Solid shaft; 214. Guide block; 215. Guide groove; 216. Second spiral groove; 217. Fixed shaft guide hole; 218. Drain port; 219. Retaining ring; 220. Spring; 221. Connecting ring;

[0051] 31. Cleaning rod; 32. Rotating ring; 33. Connecting rod; 34. First wedge; 35. First inclined surface; 36. Avoidance groove; 37. Second wedge; 38. Support plate; 39. Support plate telescopic member; 310. Fixed plate; 311. Tube body; 312. Umbrella-shaped flow guide; 313. Second sliding protrusion; 314. Cleaning rod guide hole; 315. Second inclined surface. DETAILED DESCRIPTION

[0052] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Those skilled in the art should know that the embodiments described below are part of the embodiments of the present disclosure, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative efforts shall fall within the scope of protection of the present invention.

[0053] The embodiment of the hydrochloric acid methanol tail gas absorption equipment for nicarbazine production provided by the present invention is as follows:

[0054] like Figures 1 to 22 As shown, the hydrochloric acid methanol tail gas absorption equipment for nicarbazine production (hereinafter referred to as the tail gas absorption equipment) includes an equipment body, a detection and adjustment device, and a cleaning device.

[0055] like Figures 1 to 14 As shown, the main body of the equipment includes a shell 11, a liquid inlet pipe 12, a liquid outlet pipe 13, an air inlet pipe 14, an air outlet pipe 15, an upper tube plate 16, a lower tube plate 17, a coolant inlet pipe 18, a coolant outlet pipe 19, an absorption pipe 110, and an overflow pipe 111.

[0056] The housing 11 includes a liquid inlet cylinder 112, a cooling cylinder 113, and a liquid outlet cylinder 114. The liquid inlet cylinder 112, cooling cylinder 113, and liquid outlet cylinder 114 are arranged in sequence in the vertical direction and connected by flanges. Here, the liquid inlet cylinder 112, cooling cylinder 113, and liquid outlet cylinder 114 are all cylindrical. The upper tube plate 16 is fixed between the liquid inlet cylinder 112 and the cooling cylinder 113, separating the internal space of the liquid inlet cylinder 112 from the internal space of the cooling cylinder 113; the lower tube plate 17 is fixed between the cooling cylinder 113 and the liquid outlet cylinder 114, separating the internal space of the cooling cylinder 113 from the internal space of the liquid outlet cylinder 114. A liquid inlet cavity is formed in the liquid inlet cylinder 112, and the liquid inlet cavity is located above the upper tube plate 16; a liquid outlet cavity is formed in the liquid outlet cylinder 114, and the liquid outlet cavity is located below the lower tube plate 17.

[0057] The upper tube plate 16 and the lower tube plate 17 are provided with through holes extending vertically therethrough for the absorption tubes 110 to pass through. The through holes on the upper tube plate 16 and the lower tube plate 17 are divided into a plurality of groups uniformly distributed along the circumferential direction, and each group of perforations has three perforations arranged in sequence along the radial direction. The perforations on the upper tube plate 16 and the lower tube plate 17 are directly opposite to each other vertically.

[0058] The liquid inlet pipe 12 is fixed to the side of the liquid inlet cylinder 112. The liquid inlet pipe 12 includes a horizontal section and a vertical section that are interconnected. The vertical section extends downward and is located at the center of the liquid inlet cylinder 112. The liquid outlet pipe 13 is fixed to the side of the liquid outlet cylinder 114.

[0059] Air inlet pipe 14 is fixed to the side of liquid outlet cylinder 114, located above liquid outlet pipe 13. Air outlet pipe 15 is fixed to the top of liquid inlet cylinder 112, and is fixed to the top opening of liquid inlet cylinder 112 via a flange. When absorbing exhaust gas, the exhaust gas flows upward in absorption tube 110, and the liquid used for absorption flows downward in absorption tube 110.

[0060] The coolant inlet pipe 18 and the coolant outlet pipe 19 are both fixed to the side of the cooling cylinder 113 , and the coolant inlet pipe 18 is located below the coolant outlet pipe 19 .

[0061] Among them, the structures of the shell 11, liquid inlet pipe 12, liquid outlet pipe 13, air inlet pipe 14, air outlet pipe 15, upper tube plate 16, lower tube plate 17, coolant inlet pipe 18, and coolant outlet pipe 19 are existing technologies and are not described here in detail.

[0062] Absorbent tubes 110 extend vertically, and their number is equal to and corresponds to the number of perforations in the upper and lower tube sheets 16 and 17. The upper ends of the absorbent tubes 110 extend upward through the perforations in the upper tube sheet 16, are located within the liquid inlet cylinder 112, and their lower ends penetrate the perforations in the lower tube sheet 17. The absorbent tubes 110 are fixed to both the upper and lower tube sheets 16 and 17. The absorbent tubes 110 and the perforations are hermetically sealed, and sealing structures such as sealing rings may be added.

[0063] A reduced diameter section 116 is provided near the bottom of the absorber tube 110 . The inner diameter of the reduced diameter section 116 is smaller than the inner diameters of other positions. The reduced diameter section 116 and other positions are smoothly transitioned via a slope.

[0064] like Figure 15 As shown, the top of the absorber tube 110 has an inner chamfer 115 . The top outer wall of the absorber tube 110 is provided with a first spiral groove 117 .

[0065] The number of overflow pipes 111 is equal to the number of absorption tubes 110 and corresponds one to one. The overflow pipe 111 is located in the liquid inlet cylinder 112. The overflow pipe 111 is adaptively sleeved on the top of the absorption tube 110, and the overflow pipe 111 can move up and down. An overflow port 118 is provided on the side of the overflow pipe 111. The overflow port here is a V-shaped incision. The liquid in the liquid inlet cylinder 112 enters the overflow pipe 111 through the overflow port 118, wherein there are multiple overflow ports 118 arranged along the circumferential direction. A top cover 119 is fixed on the top of the overflow pipe 111. An annular groove 120 is provided on the top cover 119. The annular groove 120 is arranged around the axis of the overflow pipe 111, and the top of the annular groove 120 has a retaining edge.

[0066] A first sliding protrusion 121 is provided on the outer wall of the overflow pipe 111 , and the first sliding protrusion 121 is located in the first spiral groove 117 . When the overflow pipe 111 rises or falls, the overflow pipe 111 rotates around its own axis under the action of the first sliding protrusion 121 and the first spiral groove 117 .

[0067] like Figures 1 to 20 As shown, the function of the detection and adjustment device is to determine whether the height of the overflow pipe 111 is appropriate and to adjust the position of the overflow pipe 111, including an upper mounting seat 21, a lower mounting seat 22, a fixed shaft 23, a collecting tube 24, an elastic support, a target rod 25, a displacement sensor 26, and an overflow pipe telescopic member 27, wherein the number of the fixed shaft 23, the collecting tube 24, the elastic support, the target rod 25, the displacement sensor 26, and the overflow pipe telescopic member 27 is equal to the number of the absorption tubes 110 and corresponds one to one.

[0068] The upper mounting seat 21 is located within the liquid inlet cylinder 112, above the liquid inlet tube 12. Specifically, the upper mounting seat 21 comprises a housing 28, a sealing plate 29, a connecting block 210, and a mounting block 211. The housing 28 opens downward, and the sealing plate 29 is fixedly mounted to the bottom of the housing 28. Together, the housing 28 and sealing plate 29 form a closed space. The mounting block 211 is located within this closed space and is fixed to the sealing plate 29. Each mounting block 211 corresponds to each absorber tube 110.

[0069] There is a gap between the side of the box body 28 and the inner wall of the liquid inlet cylinder 112 to allow gas to pass through. The bottom of the connecting block 210 is fixed to the top of the box body 28, and the top of the connecting block 210 is fixed to the outlet pipe 15. There are multiple connecting blocks 210 arranged along the circumference, and there is a gap between adjacent two connecting blocks 210 to allow gas to pass through.

[0070] The lower mounting seat 22 is fixed in the liquid outlet cylinder 114 , and the lower mounting seat 22 is located below the liquid outlet pipe 13 .

[0071] The upper end of the fixed shaft 23 is fixed on the upper mounting seat 21 , and the lower end is fixed on the lower mounting seat 22 . The fixed shaft 23 extends vertically and passes through the absorption tube 110 . The fixed shaft 23 and the absorption tube 110 are coaxially arranged.

[0072] The fixed shaft 23 includes a hollow shaft 212 at the top and a solid shaft 213 at the bottom. The hollow shaft 212 has a central hole for the target rod 25 to pass through. The top of the solid shaft 213 is provided with a horizontal through-groove, thereby forming two eccentric guide blocks 214 at the top of the solid shaft 213. The guide blocks 214 and the hollow shaft 212 are separately processed and then assembled together, specifically by welding or other methods.

[0073] A guide groove 215 and a second spiral groove 216 are defined on the outer wall of the solid shaft 213 . The guide groove 215 extends up and down. The second spiral groove 216 is located above the guide groove 215 and is communicated with the guide groove 215 .

[0074] The bottom of the collecting cylinder 24 is provided with fixed shaft guide holes 217 corresponding to the two guide blocks. The guide blocks 214 are adapted to pass through the fixed shaft guide holes 217 so that the collecting cylinder 24 can be slidably mounted on the fixed shaft 23 in the up and down directions. The collecting cylinder 24 is located in the absorption tube 110, and the collecting cylinder 24 is coaxially arranged with the absorption tube 110. The outer diameter of the collecting cylinder 24 is smaller than the inner diameter of the absorption tube 110, so that an annular space is formed between the collecting cylinder 24 and the absorption tube 110 for liquid and gas to pass through. A drain port 218 is provided on the side of the collecting cylinder 24. After the drain port 218 is opened, the liquid in the collecting cylinder 24 can flow into the absorption tube 110.

[0075] The elastic support member applies an upward elastic force to the collecting tube 24. The elastic support member includes a fixing ring 219 and a spring 220. The fixing ring 219 is fixedly sleeved on the outside of the fixed shaft 23. The spring 220 is a compression spring. The lower end of the spring 220 is fixed to the fixing ring 219, and the upper end fixes the bottom of the collecting tube 24. Figure 18 and Figure 19 As shown, fixing rings 219 are also fixed on the top and bottom of the fixed shaft 23 respectively.

[0076] The target rod 25 is fixed at the center of the bottom of the collecting tube 24 , and the target rod 25 extends upward and penetrates into the mounting block 211 of the upper mounting seat 21 .

[0077] The displacement sensor 26 and the overflow pipe telescopic member 27 are both fixedly mounted on the mounting block 211. The detection end of the displacement sensor 26 is aligned with the target rod 25 in a vertical direction, detecting the displacement of the target rod 25. The displacement sensor 26 can be a laser sensor, etc. The telescopic end of the overflow pipe telescopic member 27 extends downward through the upper mounting seat 21. A connecting ring 221 is mounted on the telescopic end of the overflow pipe telescopic member 27. The connecting ring 221 is located in the annular groove 120 and can rotate around the axis of the overflow pipe 111. At the same time, the connecting ring 221 is blocked by the retaining edge of the annular groove 120, which can drive the overflow pipe 111 to rise. In actual use, a controller is also required. The controller collects the data of the displacement sensor 26 at regular intervals. The controller pre-sets a set displacement value and a set rise value. When the displacement of the target rod 25 exceeds the set displacement value, the controller controls the overflow pipe telescopic member 27 to drive the overflow pipe 111 to move upward by the set rise value. After the overflow pipe 111 moves upward to its proper position, the controller starts a new round of data collection and control.

[0078] like Figures 1 to 14 as well as Figure 21 、 Figure 22 As shown, the cleaning device is used to clean up the debris on the inner wall of the absorption tube. The cleaning device includes a cleaning rod 31, a rotating ring 32, a connecting rod 33, and a driving component.

[0079] The number of cleaning rods 31 is equal to the number of absorption tubes 110 and corresponds one to one. The cleaning rods 31 extend up and down. The cleaning rods 31 are located on one side of the fixed shaft 23. There is a rubber layer on the outer side of the cleaning rod 31 away from the fixed shaft 23. The rubber layer is used to fit the inner wall of the absorption tube 110.

[0080] The top and bottom of the cleaning rod 31 are hinged to the fixed shaft 23 via connecting rods 33. Specifically, rotating rings 32 are rotatably mounted on the fixed rings 219 at the top and bottom of the fixed shaft 23. The rotating rings 32 are fixed relative to the fixed shaft 23 in the vertical direction. One end of the connecting rod 33 is hinged to the rotating ring 32, and the other end is hinged to the cleaning rod 31. The cleaning rod 31, the fixed shaft 23, and the two connecting rods 33 together form a parallelogram mechanism, allowing the cleaning rod 31 to translate as a whole.

[0081] A first wedge 34 is fixed to the inner side of the cleaning rod 31. A first inclined surface 35 is provided on the inner side of the bottom of the first wedge 34. The first inclined surface 35 extends downward and away from the fixed shaft 23. A clearance groove 36 is provided on the outer side of the cleaning rod 31. The clearance groove 36 is used to avoid the reduced diameter section 116 of the absorption tube 110.

[0082] The driving component drives the cleaning rod 31 to translate upward and outward, so that the outer side of the cleaning rod 31 contacts the inner wall of the absorption tube 110. The driving component includes a driving tube, a second wedge 37, a support plate 38, and a support plate telescopic member 39. The number of driving tubes and second wedges 37 is equal to the number of cleaning rods 31 and corresponds one to one.

[0083] The support plate 38 is located above the lower mounting seat 22, and the support plate telescopic member 39 is located below the lower mounting seat 22. The telescopic end of the support plate telescopic member 39 is connected to the support plate 38 and can drive the support plate 38 to move up and down. Among them, the support plate telescopic member 39 is fixed to the bottom of the liquid discharge cylinder 114 through the fixing plate 310.

[0084] The drive tube is sleeved onto the exterior of the fixed shaft 23 and is capable of moving up and down relative to the fixed shaft 23. The drive tube includes a tube body 311 and an umbrella-shaped flow guide 312. The lower end of the tube body 311 of each drive tube is fixed to the support plate 38. The tube body 311 is located below the rotating ring 32 at the top. The bottom of the tube body 311 has a larger outer diameter to accommodate the connecting rod 33 and rotating ring 32 at the bottom. A second sliding protrusion 313 is fixed to the inner wall of the tube body 311. The second sliding protrusion 313 is located in the guide groove 215 and the second spiral groove 216. When the second sliding protrusion 313 is located in the guide groove 215, the tube body 311 is guided and moved up and down. When the second sliding protrusion 313 is located in the second spiral groove 216, the second sliding protrusion 313 and the second spiral groove 216 cooperate to drive the tube body 311 to rotate as the tube body 311 moves up and down.

[0085] The umbrella-shaped flow guide 312 is fixed to the exterior of the tube body 311. Both the top and bottom of the umbrella-shaped flow guide 312 have inclined surfaces for guiding liquid and gas toward the inner wall of the absorber tube. The number of umbrella-shaped flow guides 312 is equal to the number of reduced diameter sections 116 in the absorber tube 110. Initially, the umbrella-shaped flow guide 312 is located below each reduced diameter section 116.

[0086] The umbrella-shaped guide member 312 is provided with a cleaning rod guide hole 314 extending up and down. The cleaning rod guide hole 314 allows the cleaning rod 31 to pass through up and down. When the umbrella-shaped guide member 312 rotates, it can drive the cleaning rod 31 to rotate as well.

[0087] In use: In the initial state, the overflow ports 118 in each overflow pipe 111 are at the same height; the umbrella-shaped flow guide 312 is located below the reduced diameter section 116; the second wedge 37 is located below the first wedge 34. The cleaning rod 31, under its own weight, moves away from the absorption pipe 110, sealing the drain port 218 of the collection tube 24. Liquid enters the liquid inlet body 112 through the liquid inlet pipe 12, and gas enters the liquid outlet body 114 through the gas inlet pipe 14. The liquid enters the upper tube plate 16 and overflows into the overflow pipes 111 and absorption pipe 110. The liquid forms a liquid film on the inner wall of the absorption pipe 110. As the gas flows upward in the absorption pipe 110, it contacts the liquid film and absorbs impurities in the gas.

[0088] Ideally, the liquid flow rate in each absorption tube 110 is the same; however, in actual use, the liquid flow rate in each absorption tube 110 is different, and the liquid flow rate in some absorption tubes 110 is larger. When the total liquid flow rate remains unchanged, the liquid flow rate in other absorption tubes 110 becomes smaller, resulting in uneven liquid distribution. When the liquid flow rate is large, the thickness of the liquid film in the absorption tube 110 increases, and some liquid will fall off the inner wall of the absorption tube 110, and the liquid will fall into the collection tube 24. The liquid in the collection tube 24 continues to increase, and the collection tube 24 overcomes the action of the spring 220 and moves downward, the target rod 25 descends, and the displacement sensor 26 detects the displacement of the target rod 25. When the displacement of the target rod 25 exceeds the set displacement value, the overflow pipe telescopic member 27 drives the overflow pipe 111 to move the set rise value. The overflow pipe 111 rotates while moving upward, changing the direction of the overflow port 118. After the overflow pipe 111 moves upward into position, a new round of detection and adjustment begins.

[0089] After the exhaust gas washing device has been operating for a period of time, the inner wall of the absorption tube 110 needs to be cleaned. During cleaning, the support plate telescopic member 39 drives each tube body 311 upward through the support plate 38, the second wedge block 37 pushes the first wedge block 34 upward, and the cleaning rod 31 simultaneously translates upward and outward under the action of the connecting rod 33, gradually approaching the absorption tube 110. As the tube body 311 continues to rise, the tube body 311 rotates under the action of the second sliding protrusion 313 and the second spiral groove 216, and the tube body 311 drives the umbrella-shaped guide member 312 and the cleaning rod 31 to rotate. While rotating, the cleaning rod 31 contacts the inner wall of the absorption tube 110, cleaning the inner wall of the absorption tube 110.

[0090] When the cleaning rod 31 moves horizontally close to the absorption tube 110 , the cleaning rod 31 is separated from the drainage port 218 of the collecting tube 24 , and the liquid in the collecting tube 24 is discharged.

[0091] After the umbrella-shaped flow guide 312 moves upward, it can fit into the diameter-reducing section 116 and temporarily close the absorption tube 110 , so that the liquid is gathered on the umbrella-shaped flow guide 312 , thereby improving the cleaning effect.

[0092] After cleaning is completed, the support plate telescopic member 39 drives each tube body 311 to descend, and the cleaning rod 31 is retracted under its own weight.

[0093] In other embodiments, the reduced diameter section 116 of the absorption tube 110 is eliminated, and accordingly, the umbrella-shaped flow guide 312 in the driving tube is also eliminated. In this case, a horizontally extending plate can be provided on the tube body 311, and the cleaning rod guide hole 314 is opened on the plate.

[0094] In other embodiments, the cleaning device may be eliminated, and only the detection and adjustment device may be retained.

[0095] In other embodiments, the connecting ring may be a bearing mounted on the top cover 119 , the inner ring of the bearing is fixed on the top cover 119 , and the outer ring is connected to the overflow pipe telescopic member 27 .

[0096] In other embodiments, the first sliding protrusion 121 on the overflow pipe 111 and the first spiral groove 117 on the absorption pipe 110 can be eliminated, and the overflow pipe 111 can only move up and down. In this case, the target rod 25 can be eccentrically arranged on the collection tube 24.

[0097] In addition, in the description of this specification, “a plurality of” means at least two, for example, two, three or more, etc., unless otherwise clearly and specifically defined.

Claims

1. A hydrochloric acid methanol tail gas absorption device for nicarbazine production, comprising a housing, an absorption tube, and upper and lower tube sheets disposed within the housing. The housing comprises a liquid inlet cavity located above the upper tube sheet and a liquid outlet cavity located below the lower tube sheet. The upper end of the absorption tube is fixed to the upper tube sheet and extends into the liquid inlet cavity, and the lower end of the absorption tube is fixed to the lower tube sheet. The hydrochloric acid methanol tail gas absorption equipment for nicarbazine production also includes an overflow pipe and a detection and adjustment device. The overflow pipe is slidably mounted on the upper end of the absorption pipe in the up-down direction, and an overflow port is provided on the side of the overflow pipe. The detection and adjustment device includes an upper mounting seat located in the liquid inlet chamber, a lower mounting seat located in the liquid outlet chamber, a fixed shaft, a collecting cylinder slidably assembled on the fixed shaft, and an elastic support member fixed on the fixed shaft and supporting the collecting cylinder upward, and also includes a target rod fixed on the collecting cylinder and extending up and down, the fixed shaft passes through the absorption tube up and down, the upper end of the fixed shaft is fixed on the upper mounting seat, and the lower end is fixed on the lower mounting seat, the collecting cylinder is located at the center of the absorption tube and is used to collect liquid, the upper mounting seat is provided with a displacement sensor and an overflow pipe telescopic member, the displacement sensor is used to detect the displacement of the target rod, and the overflow pipe telescopic member is connected to the overflow pipe and is used to drive the overflow pipe to rise and fall; A top cover is provided on the top of the overflow pipe, and a connecting ring is provided on the top cover. The connecting ring is relatively rotated in the circumferential direction and relatively fixedly assembled on the top cover in the vertical direction. The overflow pipe telescopic member is connected to the connecting ring. A first sliding protrusion is provided on the inner wall of the overflow pipe, and a first spiral groove is provided on the outer wall of the absorption pipe. The first sliding protrusion is slidably assembled in the first spiral groove. When the overflow pipe moves up and down, it can rotate under the action of the first spiral groove and the first sliding protrusion.

2. The hydrochloric acid methanol tail gas absorption equipment for nicarbazine production according to claim 1, characterized in that: The fixed shaft includes a hollow shaft at the top and a solid shaft at the bottom. An eccentric guide block is provided at the top of the solid shaft. The guide block is fixedly connected to the hollow shaft. The guide block passes through the collecting tube up and down. The target rod is fixed at the center position of the bottom of the collecting tube, and the target rod passes upward from the hollow shaft.

3. The hydrochloric acid methanol tail gas absorption equipment for nicarbazine production according to claim 2, characterized in that: The top of the target rod is adapted to penetrate into the upper mounting seat.

4. The hydrochloric acid methanol tail gas absorption equipment for nicarbazine production according to claim 3, characterized in that: The hydrochloric acid methanol tail gas absorption equipment for nicarbazine production includes an exhaust pipe fixed on the top of the shell, the upper mounting seat includes a box body with an opening facing downward and a sealing plate separately fixed on the opening of the box body, and the displacement sensor and the overflow pipe telescopic part are located in the space enclosed by the box body and the sealing plate.

5. The hydrochloric acid methanol tail gas absorption equipment for nicarbazine production according to any one of claims 2 to 4, characterized in that: The top cover is provided with an annular groove, and the overflow pipe is connected and rotatably assembled around its axis in the annular groove.

6. The hydrochloric acid methanol tail gas absorption equipment for nicarbazine production according to any one of claims 1 to 4, characterized in that: The cleaning device also includes a cleaning rod and a driving component. The upper and lower ends of the fixed shaft are each provided with a rotating ring. The rotating ring is relatively rotated in the circumferential direction and relatively fixedly assembled on the fixed shaft in the vertical direction. The upper and lower ends of the cleaning rod are hinged to the rotating ring via a connecting rod. The outer side of the cleaning rod has a rubber layer. A first wedge is provided on the side of the cleaning rod facing the fixed shaft. The driving component includes a driving tube that is slidably mounted on the outside of the fixed shaft and a second wedge block fixed on the outside of the driving tube. When the driving tube moves upward, the second wedge block pushes the first wedge block upward, and the cleaning rod moves upward while translating toward the inner wall of the absorption tube. The driving tube is provided with a cleaning rod through-hole for the cleaning rod to pass through. The cleaning rod can move horizontally in the cleaning rod through-hole. A second spiral groove is provided on the outer wall of the fixed shaft, and a second sliding protrusion that is slidably assembled in the second spiral groove is provided on the inner wall of the driving tube.

7. The hydrochloric acid methanol tail gas absorption equipment for nicarbazine production according to claim 6, characterized in that: A drain outlet is provided on one side of the collecting cylinder, and the cleaning rod is used to close the drain outlet. The cleaning rod is separated from the drain outlet after being translated toward the absorption pipe.

8. The hydrochloric acid methanol tail gas absorption equipment for nicarbazine production according to claim 6, characterized in that: The bottom inner side of the absorption tube has a reduced diameter section, the driving tube includes a tube body and an umbrella-shaped flow guide provided on the tube body, and the cleaning rod is provided with a through hole on the umbrella-shaped flow guide; The top and bottom of the umbrella-shaped flow guide are both provided with inclined surfaces for guiding the liquid and gas toward the inner wall of the absorption tube. The umbrella-shaped flow guide can close the reduced diameter section when moving upward with the tube body.

9. The hydrochloric acid methanol tail gas absorption equipment for nicarbazine production according to claim 6, characterized in that: The cleaning device includes a support plate located above the lower mounting seat, and the driving tubes in each absorption tube are fixed on the support plate. The cleaning device also includes a support plate telescopic member located below the lower mounting seat and connected to the support plate.

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