Hydrochloric acid methanol tail gas absorption equipment for nicarbazin production

Abstract

The invention belongs to the technical field of gas absorption and separation, and particularly relates to hydrochloric acid methanol tail gas absorption equipment for nicarbazin production, which comprises a shell, an absorption tube, an upper tube plate and a lower tube plate, the upper tube plate and the lower tube plate are arranged in the shell, a liquid inlet cavity and a liquid outlet cavity are arranged in the shell, and the upper end of the absorption tube is fixed on the upper tube plate and penetrates into the liquid inlet cavity; the lower end of the absorption tube is fixed on the lower tube plate; the device further comprises an overflow pipe and a detection adjusting device, the overflow pipe slidably sleeves the upper end of the absorption pipe, and an overflow port is formed in the side part of the overflow pipe; the detection adjusting device comprises an upper mounting seat, a lower mounting seat, a fixing shaft, a collecting barrel, an elastic supporting piece and a target rod which is fixedly arranged on the collecting barrel and extends up and down, the collecting barrel is located in the center of the absorption pipe, a displacement sensor and an overflow pipe telescopic piece are arranged on the upper mounting seat, and the displacement sensor is used for detecting the displacement amount of the target rod; the overflow pipe telescopic piece is connected with the overflow pipe and used for driving the overflow pipe to ascend and descend.

Description

Technical Field

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

[0002] In the production process of nicarbazin, especially in the steps involving hydrochloric acid and methanol as reaction media, tail gas containing volatile organic compounds and acidic gases is generated. These tail gases not only pollute the environment but also may endanger the health of operators. Therefore, effectively treating these tail gases is the key to ensuring the sustainability and compliance of the production process. Falling film reactors have been widely applied and developed in treating tail gases containing volatile organic compounds and acidic gases due to their high efficiency and energy conservation characteristics.

[0003] For example, the patent with the authorization announcement number CN219922525U discloses a multi-stage falling film absorber, which includes an absorber head, a cooling and absorption section, and a gas-liquid separation section. A liquid inlet is connected to the absorber head. Several absorption tubes are arranged inside the cooling and absorption section, and a zigzag overflow distributor connected to each absorption tube is arranged inside the absorber head. During use, the absorption liquid enters the absorber head through the liquid inlet. When there is more absorption liquid in the absorber head, it overflows into the absorption tubes through the zigzag overflow distributor and flows downward along the inner wall of the absorption tubes to form a liquid film. The waste gas flows inside the absorption tubes, and the absorption liquid and the waste gas are combined inside the absorption tubes, and the absorption liquid adsorbs harmful substances in the waste gas.

[0004] In the prior art, the absorption liquid in the absorber head enters the zigzag overflow distributor by overflowing, so as to improve the consistency of the absorption liquid flow rate in each absorption tube. However, it is found in actual use that due to reasons such as liquid inlet disturbance and the arrangement of the zigzag overflow distributor, the liquid level inside the absorber head is not horizontal, resulting in uneven flow rates in each absorption tube. The flow rate in some absorption tubes is relatively large, making the liquid film thickness relatively large, and part of the liquid detaches from the inner wall of the absorption tube, resulting in a flooding phenomenon and a low gas-liquid reaction efficiency; while the flow rate in some absorption tubes is relatively small, the formed liquid film is unstable, resulting in a dry wall phenomenon, which also leads to a low gas-liquid reaction efficiency. Summary of the Invention

[0005] The present invention provides a tail gas absorption device for hydrochloric acid methanol in nicarbazin production to solve the technical problem of low gas-liquid reaction efficiency caused by uneven flow rate distribution in the absorption tubes in the prior art.

[0006] To solve the above problems, the hydrochloric acid methanol tail gas absorption equipment for nicarbazin production provided by the present invention adopts the following technical solutions: A hydrochloric acid methanol tail gas absorption equipment for nicarbazin production includes a housing, an absorption tube, and an upper tube plate and a lower tube plate arranged in the housing. The housing has a liquid inlet cavity above the upper tube plate and a liquid outlet cavity below the lower tube plate. The upper end of the absorption tube is fixed on the upper tube plate and penetrates into the liquid inlet cavity, and the lower end of the absorption tube is fixed on the lower tube plate; The hydrochloric acid methanol tail gas absorption equipment for nicarbazin production also includes an overflow pipe and a detection and adjustment device. The overflow pipe is slidably sleeved on the upper end of the absorption tube in the vertical direction, and an overflow port is arranged on the side of the overflow pipe; The detection and adjustment device includes an upper mounting seat located in the liquid inlet cavity, a lower mounting seat located in the liquid outlet cavity, and also includes 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 vertically. The fixed shaft penetrates the absorption tube vertically. 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 central position of the absorption tube and is used to collect liquid. A displacement sensor and an overflow pipe telescopic member are arranged on the upper mounting seat. 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.

[0007] During use, if the liquid flow rate in the absorption tube is large, part of the liquid will fall into the collecting cylinder. The collecting cylinder moves downward against the action of the elastic support member, 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 pipe telescopic member drives the overflow pipe to rise, the overflow port rises, and the amount of liquid entering the overflow pipe is reduced; Under the condition that the total flow rate remains unchanged, the liquid flow rate in other overflow pipes can be increased to balance the liquid flow rate in each absorption tube. In the present invention, by arranging a fixed shaft and a collecting cylinder in the absorption tube, the liquid separated from the inner wall of the absorption tube can be collected, so as to achieve 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 and gas-liquid exchange occurs at the liquid film, the fixed shaft and the collecting cylinder are arranged at the central position of the absorption tube, and the gas flows through the annular spaces between the fixed shaft and the absorption tube and between the collecting cylinder and the absorption tube, avoiding the gas flowing at the central position of the absorption tube and forcing the gas to flow to the liquid film, thereby improving the reaction efficiency.

[0008] Preferably, the fixed shaft includes a hollow shaft at the top and a solid shaft at the bottom. An eccentric guide block is arranged at the top of the solid shaft, and the guide block is fixedly connected to the hollow shaft. The guide block penetrates the collecting cylinder vertically. The target rod is fixed at the central position of the bottom of the collecting cylinder and passes upward through the hollow shaft.

[0009] Preferably, the top of the target rod is fitted and penetrated into the upper mounting seat.

[0010] Preferably, the tail gas absorption device for nicarbazin production using hydrochloric acid methanol includes an air outlet pipe fixed to the top of the shell. The upper mounting seat includes a box body with an opening facing downwards and a sealing plate fixedly installed on the opening of the box body in a split manner. The displacement sensor and the telescopic member of the overflow pipe are located in the space formed by the enclosure of the box body and the sealing plate.

[0011] The displacement sensor and the telescopic member of the overflow pipe are located in the enclosed space, separating the gas from the displacement sensor and the telescopic member of the overflow pipe, and preventing acidic substances in the gas from corroding and damaging the displacement sensor and the telescopic member of the overflow pipe.

[0012] Preferably, a top cover is provided at the top of the overflow pipe, and a connecting ring is provided on the top cover. The connecting ring is circumferentially relatively rotatable and relatively fixed in the vertical direction and is assembled on the top cover. The telescopic member of the overflow pipe is connected to the connecting ring; First sliding protrusions are provided on the inner wall of the overflow pipe, and first spiral grooves are provided on the outer wall of the absorption pipe. The first sliding protrusions are slidably assembled in the first spiral grooves, and the overflow pipe can rotate under the action of the first spiral grooves and the first sliding protrusions when moving up and down.

[0013] The overflow pipe can rotate while lifting and lowering, and can change the orientation of the overflow port; when the overflow pipes are arranged in a straight line in sequence, changing the orientation of the overflow port can also adjust the flow rate in the overflow pipe; and the target rod is located at the central position of the overflow pipe, and the rotation of the overflow pipe will not affect the detection of the target rod by the displacement sensor.

[0014] Preferably, a ring groove is provided on the top cover, and the connecting ring is rotatably assembled around the axis of the overflow pipe in the ring groove.

[0015] Preferably, a cleaning device is further included. The cleaning device includes a cleaning rod and a driving component. Rotating rings are provided at both the upper and lower ends of the fixed shaft. The rotating rings are circumferentially relatively rotatable and relatively fixed in the vertical direction and are assembled on the fixed shaft. Both the upper and lower ends of the cleaning rod are hinged to the rotating rings through connecting rods. A rubber layer is provided on the outer side of the cleaning rod, and a first wedge block is provided on the side of the cleaning rod facing the fixed shaft; The driving component includes a driving pipe slidably sleeved outside the fixed shaft and a second wedge block fixed outside the driving pipe. When the driving pipe moves upwards, the second wedge block pushes the first wedge block upwards, and the cleaning rod moves upwards and translates towards the inner wall of the absorption pipe at the same time. A cleaning rod perforation for the cleaning rod to pass through is provided on the driving pipe, and the cleaning rod can horizontally move in the cleaning rod perforation. Second spiral grooves are provided on the outer wall of the fixed shaft, and second sliding protrusions slidably assembled in the second spiral grooves are provided on the inner wall of the driving pipe.

[0016] During long-term use, debris will adhere to the inner wall of the absorption tube, affecting the stability of the liquid film, and thus cleaning is required. During cleaning, the drive tube moves upward. Through the cooperation of the second wedge and the first wedge, the cleaning rod moves upward and outward in translation. The cleaning rod adheres to the inner wall of the absorption tube. While the drive tube moves upward, it rotates, driving the cleaning rod to rotate and cleaning the inner wall of the absorption tube.

[0017] Preferably, a drain port is provided on one side of the collection cylinder. The cleaning rod is used to close the drain port, and after the cleaning rod translates towards the absorption tube, it separates from the drain port.

[0018] Preferably, the inner bottom of the absorption tube has a reduced-diameter section. The drive tube includes a tube body and an umbrella-shaped flow guide member provided on the tube body. The cleaning rod is perforated on the umbrella-shaped flow guide member. Both the top and bottom of the umbrella-shaped flow guide member have inclined surfaces for guiding liquid and gas towards the inner wall of the absorption tube. When the umbrella-shaped flow guide member moves upward with the tube body, it can close the reduced-diameter section.

[0019] When the umbrella-shaped flow guide member is not cleaning, the inclined surface on the umbrella-shaped flow guide member can guide the gas flow towards the inner wall of the absorption tube, enabling the gas and liquid to react and absorb at the liquid film. During cleaning, the umbrella-shaped flow guide member can close the reduced-diameter section, cutting off the liquid flow, causing the liquid to accumulate at the umbrella-shaped flow guide member, filling the absorption tube with liquid, and improving the cleaning effect. When not cleaning, the reduced-diameter section can cause the liquid in the absorption tube to accumulate. If the liquid film above the reduced-diameter section is not fully formed, the liquid can be re-formed into a liquid film through the accumulation effect of the reduced-diameter section.

[0020] Preferably, the cleaning device includes a support plate located above the lower mounting base. The drive tubes in each absorption tube are fixed to the support plate. The cleaning device further includes a support plate telescopic member located below the lower mounting base and connected to the support plate.

[0021] The beneficial effects are 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 cylinder. The collection cylinder moves downward against the action of the elastic support member, 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 telescopic member of the overflow pipe drives the overflow pipe to rise, the overflow port rises, and the amount of liquid entering the overflow pipe is reduced; under the condition of constant total flow rate, the liquid flow rate in other overflow pipes can be increased to balance the liquid flow rate in each absorption tube. In the present invention, by arranging a fixed shaft in the absorption tube, the collection cylinder can collect the liquid that detaches from the inner wall of the absorption tube, so as to achieve 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, gas-liquid exchange occurs at the liquid film. The fixed shaft and the collection cylinder are arranged at the central position 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 cylinder and the absorption tube, avoiding the gas flowing at the central position of the absorption tube and forcing the gas to flow to the liquid film, thereby improving the reaction efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is the front view of the hydrochloric acid methanol tail gas absorption device for nicarbazin production; Figure 2 is the top view of the hydrochloric acid methanol tail gas absorption device for nicarbazin production; Figure 3 is Figure 2 the sectional view of the A-A section in Figure 4 is Figure 3 the enlarged view at A in Figure 5 is Figure 3 the enlarged view at B in Figure 6 is Figure 3 the enlarged view at C in Figure 7 is Figure 3 the enlarged view at D in Figure 8 is Figure 3 the enlarged view at E in Figure 9 is Figure 3 the enlarged view at F in Figure 10 is the hydrochloric acid methanol tail gas absorption device for nicarbazin production after removing the air outlet pipe, the liquid inlet cylinder body, and the cooling cylinder body (only showing three groups of absorption tubes); Figure 11 is Figure 10 the enlarged view at G in Figure 12The hydrochloric acid-methanol tail gas absorption equipment for nicarbazin production after removing the air outlet pipe, liquid inlet cylinder body, cooling cylinder body, upper tube sheet, and lower tube sheet (only the structure at 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); Figure 13 is Figure 12 the enlarged view of the H position in Figure 14 is Figure 12 the enlarged view of the I position in Figure 15 is the structural schematic diagram of the top of the absorption pipe; Figure 16 is the structural schematic diagram of the first perspective of the overflow pipe; Figure 17 is the structural schematic diagram of the second perspective of the overflow pipe; Figure 18 is the structural schematic diagram of the intersection position of the hollow shaft and the solid shaft in the fixed shaft; Figure 19 is the structural schematic diagram of the bottom of the fixed shaft; Figure 20 is the structural schematic diagram of the collection cylinder and the target rod; Figure 21 is the structural schematic diagram of the drive pipe; Figure 22 is the structural schematic diagram of the cleaning rod.

[0023] Explanation of reference numerals: 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 pipe; 111. Overflow pipe; 112. Liquid inlet cylinder body; 113. Cooling cylinder body; 114. Liquid outlet cylinder body; 115. Inner chamfer; 116. Reduced diameter section; 117. First spiral groove; 118. Overflow port; 119. Top cover; 120. Ring groove; 121. First sliding protrusion; 21. Upper mounting seat; 22. Lower mounting seat; 23. Fixed shaft; 24. Collection cylinder; 25. Target rod; 26. Displacement sensor; 27. Overflow pipe telescopic member; 28. Box body; 29. Sealing 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. Drainage port; 219. Fixed ring; 220. Spring; 221. Connecting ring; 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. Pipe body; 312. Umbrella-shaped flow guide member; 313. Second sliding protrusion; 314. Cleaning rod guide hole; 315. Second inclined surface. Detailed implementation manner

[0024] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings 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 creative efforts belong to the scope of protection of the present invention.

[0025] An embodiment of the hydrochloric acid methanol tail gas absorption device for nicarbazin production provided by the present invention: As Figures 1 to 22 shown, the hydrochloric acid methanol tail gas absorption device for nicarbazin production (hereinafter simply referred to as the tail gas absorption device) includes a device main body, a detection and adjustment device, and a cleaning device.

[0026] As Figures 1 to 14 shown, the device main body includes a housing 11, a liquid inlet pipe 12, a liquid outlet pipe 13, a gas inlet pipe 14, a gas outlet pipe 15, an upper pipe plate 16, a lower pipe plate 17, a coolant inlet pipe 18, a coolant outlet pipe 19, an absorption pipe 110, and an overflow pipe 111.

[0027] The housing 11 includes a liquid inlet cylinder 112, a cooling cylinder 113, and a liquid outlet cylinder 114. The liquid inlet cylinder 112, the cooling cylinder 113, and the liquid outlet cylinder 114 are arranged in sequence in the vertical direction and are connected by flanges. Here, the liquid inlet cylinder 112, the cooling cylinder 113, and the liquid outlet cylinder 114 are all cylinders. The upper pipe 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 pipe 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 pipe plate 16; a liquid outlet cavity is formed in the liquid outlet cylinder 114, and the liquid outlet cavity is located below the lower pipe plate 17.

[0028] Perforations that penetrate up and down are provided on the upper pipe plate 16 and the lower pipe plate 17, and the absorption pipe 110 passes through the perforations; among them, the perforations on the upper pipe plate 16 and the lower pipe plate 17 are divided into multiple groups evenly distributed along the circumferential direction, and each group of perforations has three arranged in sequence along the radial direction, and the perforations on the upper pipe plate 16 and the lower pipe plate 17 are vertically aligned.

[0029] The liquid inlet pipe 12 is fixed to the side of the liquid inlet cylinder body 112. The liquid inlet pipe 12 includes a horizontal section and a vertical section that are in communication with each other. The vertical section extends downward and is located at the central position of the liquid inlet cylinder body 112. The liquid outlet pipe 13 is fixed to the side of the liquid outlet cylinder body 114.

[0030] The air inlet pipe 14 is fixed to the side of the liquid outlet cylinder body 114, and the air inlet pipe 14 is located above the liquid outlet pipe 13. The air outlet pipe 15 is fixed to the top of the liquid inlet cylinder body 112, and it is fixed to the top opening of the liquid inlet cylinder body 112 through a flange. When absorbing the tail gas, the waste gas flows upward in the absorption pipe 110, and the liquid used for absorption flows downward in the absorption pipe 110.

[0031] The coolant inlet pipe 18 and the coolant outlet pipe 19 are both fixed to the side of the cooling cylinder body 113, and the coolant inlet pipe 18 is located below the coolant outlet pipe 19.

[0032] Among them, the structures of the housing 11, the liquid inlet pipe 12, the liquid outlet pipe 13, the air inlet pipe 14, the air outlet pipe 15, the upper tube sheet 16, the lower tube sheet 17, the coolant inlet pipe 18, and the coolant outlet pipe 19 are prior arts and will not be elaborated here.

[0033] The absorption pipe 110 extends vertically up and down. The number of absorption pipes 110 is equal to and corresponds one by one to the number of perforations in the upper tube sheet 16 and the lower tube sheet 17. The upper end of the absorption pipe 110 passes upward through the perforation of the upper tube sheet 16. The upper end of the absorption pipe 110 is located in the liquid inlet cylinder body 112, and the lower end of the absorption pipe 110 penetrates into the perforation of the lower tube sheet 17. The absorption pipe 110 is fixed to both the upper tube sheet 16 and the lower tube sheet 17. The absorption pipe 110 and the perforations are in sealing fit, and specifically, sealing structures such as sealing rings can be added.

[0034] There is a reduced-diameter section 116 at a position near the bottom in the absorption pipe 110. The inner diameter of the reduced-diameter section 116 is smaller than that of other positions, and the reduced-diameter section 116 and other positions are smoothly transitioned through a slope.

[0035] As Figure 15 shown, the top of the absorption pipe 110 has an inner chamfer 115. The outer wall of the top of the absorption pipe 110 is provided with a first spiral groove 117.

[0036] The number of overflow pipes 111 is equal to and corresponds one by one with the number of absorption pipes 110. The overflow pipes 111 are located in the liquid inlet cylinder body 112. The overflow pipes 111 are adaptively sleeved on the tops of the absorption pipes 110 and can move up and down. An overflow port 118 is formed on the side of the overflow pipe 111. Here, the overflow port is a V-shaped cut. The liquid in the liquid inlet cylinder body 112 enters the overflow pipe 111 through the overflow port 118. Among them, there are multiple overflow ports 118 arranged circumferentially. A top cover 119 is fixed to the top of the overflow pipe 111. A ring groove 120 is formed on the top cover 119. The ring groove 120 is arranged around the axis of the overflow pipe 111, and a retaining edge is provided at the top of the ring groove 120.

[0037] A first sliding protrusion 121 is formed on the outer wall of the overflow pipe 111. The first sliding protrusion 121 is located in the first spiral groove 117. When the overflow pipe 111 rises and falls, under the action of the first sliding protrusion 121 and the first spiral groove 117, the overflow pipe 111 rotates around its own axis.

[0038] As Figures 1 to 20 shown, the function of the detection and adjustment device is to determine whether the height of the overflow pipe 111 is appropriate and adjust the position of the overflow pipe 111, including an upper mounting seat 21, a lower mounting seat 22, a fixed shaft 23, a collection cylinder 24, an elastic support member, a target rod 25, a displacement sensor 26, and an overflow pipe telescopic member 27. Among them, the number of the fixed shaft 23, the collection cylinder 24, the elastic support member, the target rod 25, the displacement sensor 26, and the overflow pipe telescopic member 27 is equal to and corresponds one by one with the number of absorption pipes 110.

[0039] The upper mounting seat 21 is located in the liquid inlet cylinder body 112 and is above the liquid inlet pipe 12. Specifically, the upper mounting seat 21 includes a box body 28, a sealing plate 29, a connecting block 210, and a mounting block 211. The box body 28 has an opening facing downwards. The sealing plate 29 is fixedly installed at the bottom of the box body 28. The box body 28 and the sealing plate 29 enclose a closed space. The mounting block 211 is located in this closed space and is fixed to the sealing plate 29. The mounting blocks 211 correspond to the absorption pipes 110 one by one.

[0040] There is a gap between the side of the box body 28 and the inner wall of the liquid inlet cylinder body 112 for 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 air outlet pipe 15. There are multiple connecting blocks 210 arranged circumferentially, and there is a gap between adjacent two connecting blocks 210 for gas to pass through.

[0041] The lower mounting seat 22 is fixed in the liquid outlet cylinder body 114 and is below the liquid outlet pipe 13.

[0042] The upper end of the fixed shaft 23 is fixed to the upper mounting base 21, and the lower end is fixed to the lower mounting base 22. The fixed shaft 23 extends vertically as a whole and passes through the absorption tube 110. The fixed shaft 23 is coaxially arranged with the absorption tube 110.

[0043] 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 opening for the target rod 25 to pass through. A horizontally penetrating through groove is provided at the top of the solid shaft 213, so that two eccentric guide blocks 214 are formed at the top of the solid shaft 213. The guide blocks 214 are separately processed from the hollow shaft 212 and then assembled together, and welding or other methods can be specifically used.

[0044] A guide groove 215 and a second spiral groove 216 are provided on the outer wall of the solid shaft 213. The guide groove 215 extends vertically, and the second spiral groove 216 is located above the guide groove 215. The second spiral groove 216 communicates with the guide groove 215.

[0045] Corresponding to the two guide blocks, fixed shaft guide holes 217 are provided at the bottom of the collection cylinder 24. The guide blocks 214 pass through the fixed shaft guide holes 217 in a fitting manner, so that the collection cylinder 24 is slidably sleeved on the fixed shaft 23 in the vertical direction. The collection cylinder 24 is located in the absorption tube 110 and is coaxially arranged with the absorption tube 110. The outer diameter of the collection cylinder 24 is smaller than the inner diameter of the absorption tube 110, so that an annular space is formed between the collection 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 collection cylinder 24. After the drain port 218 is opened, the liquid in the collection cylinder 24 can flow into the absorption tube 110.

[0046] The elastic support member applies an upward elastic force to the collection cylinder 24. The elastic support member includes a fixed ring 219 and a spring 220. The fixed ring 219 is fixedly sleeved outside the fixed shaft 23. The spring 220 is sleeved on the fixed shaft 23. The spring 220 is a compression spring. The lower end of the spring 220 is fixed to the fixed ring 219, and the upper end is fixed to the bottom of the collection cylinder 24. As Figure 18 and Figure 19 shown, fixed rings 219 are also respectively fixed at the top and bottom of the fixed shaft 23.

[0047] The target rod 25 is fixed at the central position of the bottom of the collection cylinder 24. The target rod 25 extends upward and penetrates into the mounting block 211 of the upper mounting base 21.

[0048] The displacement sensor 26 and the telescopic member 27 of the overflow pipe are both fixedly installed on the mounting block 211. The detection end of the displacement sensor 26 is vertically aligned with the target rod 25 to detect the displacement of the target rod 25. Here, the displacement sensor 26 can be a laser sensor or the like. The telescopic end of the telescopic member 27 of the overflow pipe passes downward through the upper mounting seat 21. A connecting ring 221 is installed on the telescopic end of the telescopic member 27 of the overflow pipe. The connecting ring 221 is located in the annular groove 120. The connecting ring 221 can rotate around the axis of the overflow pipe 111. At the same time, the connecting ring 221 is blocked by the retaining edge on the annular groove 120, which can drive the overflow pipe 111 to rise. In actual use, a controller also needs to be equipped. The controller collects the value of the displacement sensor 26 at regular intervals. The controller will preset a set displacement value and a set rising value. When the displacement of the target rod 25 exceeds the set displacement value, the controller controls the telescopic member 27 of the overflow pipe to drive the overflow pipe 111 to move upward by the set rising value. After the overflow pipe 111 moves upward in place, the controller starts a new round of collection and control.

[0049] As Figures 1 to 14 and Figure 21 , Figure 22 shown, the function of the cleaning device is to clean the debris on the inner wall of the absorption pipe. The cleaning device includes a cleaning rod 31, a rotating ring 32, a connecting rod 33, and a driving component.

[0050] The number of cleaning rods 31 is equal to and corresponds one by one to the number of each absorption pipe 110. The cleaning rods 31 extend vertically. 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 far from the fixed shaft 23, and the rubber layer is used to fit with the inner wall of the absorption pipe 110.

[0051] The top and bottom of the cleaning rod 31 are both hinged to the fixed shaft 23 through the connecting rod 33. Specifically, rotating rings 32 are rotatably installed on the fixing rings 219 at the top and bottom of the fixed shaft 23. In the vertical direction, the rotating ring 32 is fixed relative to the fixed shaft 23. 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, and the cleaning rod 31 can be translated as a whole.

[0052] A first wedge block 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 block 34. The first inclined surface 35 extends downward and away from the fixed shaft 23. An avoidance groove 36 is provided on the outer side of the cleaning rod 31, and the function of the avoidance groove 36 is to avoid the reduced-diameter section 116 of the absorption pipe 110.

[0053] The function of the driving component is to drive the cleaning rod 31 to translate upward and outward, so that the outer side of the cleaning rod 31 is attached to the inner wall of the absorption tube 110. The driving component includes a driving tube, a second wedge block 37, a support plate 38, and a support plate telescopic member 39. The number of the driving tubes and the second wedge blocks 37 is equal to the number of the cleaning rods 31 and corresponds one by one.

[0054] The support plate 38 is located above the lower mounting base 22, the support plate telescopic member 39 is located below the lower mounting base 22, and 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 outlet cylinder 114 through a fixing plate 310.

[0055] The driving tube is sleeved outside the fixed shaft 23, and the driving tube can move up and down relative to the fixed shaft 23. The driving tube includes a tube body 311 and an umbrella-shaped flow guiding member 312. The lower ends of the tube bodies 311 of each driving tube are fixed to the support plate 38. The tube body 311 is located below the rotating ring 32 at the top. Among them, the outer diameter of the bottom of the tube body 311 is larger and is used to accommodate the bottom connecting rod 33 and the rotating ring 32. A second sliding protrusion 313 is fixed on the inner wall of the tube body 311. The second sliding protrusion 313 is located in the guiding groove 215 and the second spiral groove 216. When the second sliding protrusion 313 is located in the guiding groove 215, the tube body 311 moves up and down for guiding. When the second sliding protrusion 313 is located in the second spiral groove 216, when the tube body 311 moves up and down, it can drive the tube body 311 to rotate by relying on the cooperation of the second sliding protrusion 313 and the second spiral groove 216.

[0056] The umbrella-shaped flow guiding member 312 is fixed outside the tube body 311. The top and bottom of the umbrella-shaped flow guiding member 312 both have inclined surfaces for guiding the flow, and can guide the liquid and gas to flow towards the inner wall of the absorption tube. The number of the umbrella-shaped flow guiding members 312 is equal to the number of the reduced diameter sections 116 in the absorption tube 110. In the initial state, the umbrella-shaped flow guiding member 312 is located below each reduced diameter section 116.

[0057] The umbrella-shaped flow guiding member 312 is provided with a cleaning rod guiding hole 314 extending up and down. The cleaning rod guiding hole 314 allows the cleaning rod 31 to pass through up and down, and can drive the cleaning rod 31 to rotate when the umbrella-shaped flow guiding member 312 rotates.

[0058] Usage process: In the initial state, the overflow ports 118 in each overflow pipe 111 are at the same height; the umbrella-shaped guide member 312 is located below the reduced-diameter section 116; the second wedge 37 is located below the first wedge 34, and the cleaning rod 31 is away from the absorption pipe 110 under its own weight, and the cleaning rod 31 closes the drain port 218 of the collection cylinder 24. Liquid enters the liquid inlet cylinder 112 through the liquid inlet pipe 12, and gas enters the liquid outlet cylinder 114 through the gas inlet pipe 14. The liquid enters the upper tube sheet 16 and enters each overflow pipe 111 and absorption pipe 110 by overflow. A liquid film is formed on the inner wall of the absorption pipe 110. When the gas flows upward in the absorption pipe 110, it contacts the liquid film, and the liquid absorbs the impurities in the gas.

[0059] Ideally, the liquid flow rates in each absorption pipe 110 are the same; however, in actual use, the liquid flow rates in each absorption pipe 110 are different. The liquid flow rate in some absorption pipes 110 is larger. With the total liquid flow rate remaining unchanged, the liquid flow rate in other absorption pipes 110 becomes smaller, resulting in uneven liquid distribution. When the liquid flow rate is larger, the thickness of the liquid film in the absorption pipe 110 increases, and some liquid will fall off from the inner wall of the absorption pipe 110. The liquid drops into the collection cylinder 24, and the liquid in the collection cylinder 24 continuously increases. The collection cylinder 24 moves downward against the action of the spring 220, 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 up by a set rising value. While the overflow pipe 111 moves upward, it rotates to change the orientation of the overflow port 118. After the overflow pipe 111 moves upward in place, a new round of detection and adjustment begins.

[0060] After the tail gas washing device works for a period of time, the inner wall of the absorption pipe 110 needs to be cleaned. During cleaning, the support plate telescopic member 39 drives each pipe body 311 to move upward through the support plate 38. The second wedge 37 pushes the first wedge 34 upward, and the cleaning rod 31 simultaneously moves upward and outward under the action of the connecting rod 33, and the cleaning rod 31 gradually approaches the absorption pipe 110. As the pipe body 311 continues to rise, the pipe body 311 rotates under the action of the second sliding protrusion 313 and the second spiral groove 216. The pipe 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 pipe 110 to clean the inner wall of the absorption pipe 110.

[0061] When the cleaning rod 31 translates close to the absorption pipe 110, the cleaning rod 31 disengages from the drain port 218 of the collection cylinder 24, and the liquid in the collection cylinder 24 is discharged.

[0062] After the umbrella-shaped flow guide member 312 moves upward, it can fit with the reduced-diameter section 116 to temporarily seal the absorption tube 110, so that the liquid accumulates on the umbrella-shaped flow guide member 312, improving the cleaning effect.

[0063] After the cleaning is completed, the support plate telescopic member 39 drives each tube body 311 to descend, and the cleaning rod 31 retracts under its own weight.

[0064] In other embodiments, the reduced-diameter section 116 of the absorption tube 110 is cancelled, and correspondingly, the umbrella-shaped flow guide member 312 in the drive tube is also cancelled. At this time, a horizontally extending plate body can be provided on the tube body 311, and the cleaning rod guide hole 314 is opened on the plate body.

[0065] In other embodiments, the cleaning device can be cancelled, and only the detection and adjustment device is retained.

[0066] In other embodiments, the connecting ring can be a bearing installed 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.

[0067] In other embodiments, the first sliding protrusion 121 on the overflow pipe 111 and the first spiral groove 117 on the absorption tube 110 can be cancelled, and the overflow pipe 111 can only move up and down. At this time, the target rod 25 can be eccentrically arranged on the collection cylinder 24.

[0068] In addition, in the description of this specification, the meaning of "a plurality of" is at least two, such as two, three or more, etc., unless otherwise clearly and specifically defined.

Claims

1. An exhaust gas absorption device for nicarbazin production using hydrochloric acid methanol, comprising a housing, an absorption tube, and an upper tube plate and a lower tube plate disposed inside the housing. The housing has a liquid inlet chamber above the upper tube plate and a liquid outlet chamber below the lower tube plate. The upper end of the absorption tube is fixed on the upper tube plate and penetrates into the liquid inlet chamber, and the lower end of the absorption tube is fixed on the lower tube plate; it is characterized in that, The tail gas absorption device for nicarbazin production using hydrochloric acid methanol also includes an overflow pipe and a detection and adjustment device. The overflow pipe is slidably sleeved on the upper end of the absorption pipe in the up and 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 collection cylinder slidably assembled on the fixed shaft, and an elastic support member fixed on the fixed shaft and supporting the collection cylinder upward. It also includes a target rod fixed on the collection cylinder and extending up and down. The fixed shaft penetrates the absorption pipe 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 collection cylinder is located at the central position of the absorption pipe and is used for collecting 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, and the overflow pipe telescopic member is connected to the overflow pipe and is used to drive the overflow pipe to rise and fall.

2. The hydrochloric acid methanol tail gas absorption device for nicarbazin production according to claim 1, wherein 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, and the guide block is fixedly connected to the hollow shaft. The guide block penetrates the collection cylinder up and down. The target rod is fixed at the central position of the bottom of the collection cylinder and passes upward through the hollow shaft.

3. The tail gas absorption device for nicarbazin production using hydrochloric acid methanol according to claim 2, characterized in that, The top of the target rod is fitted and inserted into the upper mounting seat.

4. The tail gas absorption device for nicarbazin production using hydrochloric acid methanol according to claim 3, characterized in that, The tail gas absorption device for nicarbazin production using hydrochloric acid methanol includes an air outlet 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. The displacement sensor and the overflow pipe telescopic member are located in the space formed by the box body and the sealing plate.

5. The tail gas absorption device for nicarbazin production using hydrochloric acid methanol according to claim 2 or 3 or 4, characterized in that A top cover is provided at the top of the overflow pipe, and a connecting ring is provided on the top cover. The connecting ring is circumferentially relatively rotatable and relatively fixed in the up and down direction on the top cover. The overflow pipe telescopic member is connected to the connecting ring. First sliding protrusions are provided on the inner wall of the overflow pipe, and first spiral grooves are provided on the outer wall of the absorption pipe. The first sliding protrusions are slidably assembled in the first spiral grooves, and the overflow pipe can rotate under the action of the first spiral grooves and the first sliding protrusions when moving up and down.

6. The tail gas absorption device for nicarbazin production using hydrochloric acid methanol according to claim 5, characterized in that, A ring groove is provided on the top cover, and the connecting ring is rotatably assembled around the axis of the overflow pipe in the ring groove.

7. The tail gas absorption device for nicarbazin production using hydrochloric acid methanol according to any one of claims 1-4, characterized in that, It also includes a cleaning device. The cleaning device includes a cleaning rod and a driving component. Rotating rings are provided at both the upper and lower ends of the fixed shaft. The rotating rings are circumferentially relatively rotatable and relatively fixed in the up and down direction on the fixed shaft. Both the upper and lower ends of the cleaning rod are hinged to the rotating rings through connecting rods. A rubber layer is provided on the outer side of the cleaning rod, and a first wedge block is provided on the side of the cleaning rod facing the fixed shaft. The driving component includes a driving pipe slidably sleeved outside the fixed shaft and a second wedge block fixed outside the driving pipe. When the driving pipe moves upward, the second wedge block pushes the first wedge block upward. While the cleaning rod moves upward, it translates toward the inner wall of the absorption pipe. A cleaning rod through hole for the cleaning rod to pass through is provided on the driving pipe, and the cleaning rod can move horizontally in the cleaning rod through hole. Second spiral grooves are provided on the outer wall of the fixed shaft, and second sliding protrusions slidably assembled in the second spiral grooves are provided on the inner wall of the driving pipe.

8. The tail gas absorption device for nicarbazin production using hydrochloric acid methanol according to claim 7, characterized in that, A drain port is provided on one side of the collection cylinder, and the cleaning rod is used to close the drain port. The cleaning rod separates from the drain port after translating toward the absorption pipe.

9. The tail gas absorption device for nicarbazin production using hydrochloric acid methanol according to claim 7, characterized in that, The inner side of the bottom of the absorption tube has a reduced-diameter section. The drive tube includes a tube body and an umbrella-shaped flow guide member provided on the tube body. The cleaning rod is perforated on the umbrella-shaped flow guide member. Both the top and the bottom of the umbrella-shaped flow guide member have inclined surfaces for guiding liquid and gas towards the inner wall of the absorption tube. The umbrella-shaped flow guide member can close the reduced-diameter section when moving upward along with the tube body.

10. The tail gas absorption device for nicarbazin production using hydrochloric acid methanol according to claim 7, characterized in that, The cleaning device includes a support plate located above the lower mounting seat. The drive tubes in each absorption tube are fixed to the support plate. The cleaning device further includes a support plate telescopic member located below the lower mounting seat and connected to the support plate.

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