Purge gas recovery treatment system

Abstract

The invention relates to the technical field of purge gas recovery, in particular to a purge gas recovery treatment system which comprises a tank body, a tank cover is mounted at the top of the tank body, a placement seat is fixedly connected to the interior of the tank body, a plurality of ceramic membranes are mounted between the placement seat and the tank cover, a cleaning assembly is arranged in the tank body, and an exhaust pipe is fixedly communicated with the bottom of the tank body. A pressure control valve is mounted on the exhaust pipe; according to the invention, purge gas is pressurized and injected into the tank body through the spiral gas inlet pipe, micromolecular hydrogen is forced to penetrate through the ceramic membrane for separation, and is independently separated through the recovery pipe and sent to the fuel gas pipe network to be used as fuel gas, so that secondary utilization of waste gas recovery is realized, and a large amount of energy waste is reduced; and in the separation process, the impeller is driven to rotate through the lifting motion of the movable plate in combination with purge gas flow, and the cleaning sleeve is driven to synchronously rotate in the lifting process, so that the ceramic membrane micropores are comprehensively cleaned, and the efficient energy recovery efficiency is guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of purge gas recovery, and in particular to a purge gas recovery and processing system. Background Art

[0002] The carbonylation unit mainly dries dimethyl ether and CO separately and mixes them into a mixture in a certain ratio to achieve certain reaction conditions to synthesize crude methyl acetate. In the process of carbonylation of dimethyl ether to methyl acetate, in addition to the generated methyl acetate, there are also unreacted CO, DME and non-condensable gas generated by the reaction, water and trace amounts of other by-products. The generated components must be separated before the methyl acetate product can be obtained.

[0003] However, in the conventional separation side reaction recovery and treatment system, the components generated by the separation side reaction are sequentially treated through a purge gas depyridine tank, a purge gas inlet and outlet heat exchanger, a scrubber and a cryogenic molecular sieve adsorber, and the obtained purge gas is directly sent to a flare for combustion to achieve the effect of recycling. However, in this process, the hydrogen-rich purge gas is directly sent to a flare for combustion, which makes it impossible to effectively and fully reuse the rich hydrogen, resulting in unnecessary energy waste.

[0004] In view of the above technical defects, a solution is now proposed. Summary of the invention

[0005] The purpose of the present invention is to provide a purge gas recovery and treatment system, which injects the purge gas after carbonylation reaction treatment into the tank body through a spiral air inlet pipe, forcing small molecular hydrogen to penetrate the ceramic membrane for separation, and separate it separately through a recovery pipe and send it to the fuel gas network for use as fuel gas, thereby realizing the secondary utilization of waste gas recovery and reducing a large amount of energy waste; and in the separation process, through the lifting and lowering movement of the movable plate, combined with the purge gas flow, the impeller is driven to rotate, and the cleaning sleeve is driven to rotate synchronously during the lifting process, thereby realizing comprehensive cleaning of the micropores of the ceramic membrane and ensuring efficient energy recovery efficiency, so as to solve the above-mentioned technical defects.

[0006] The object of the present invention can be achieved through the following technical solutions: a purge gas recovery and processing system, comprising a tank body, a tank cover is installed on the top of the tank body, and a placement seat is fixedly connected to the inside of the tank body, a plurality of ceramic membranes are installed between the placement seat and the tank cover, a mounting groove plugged with corresponding ceramic membranes is opened on the top of the placement seat, a connecting cavity connected to the plurality of mounting grooves is opened inside the placement seat, and a recovery pipe that runs through the outside of the tank body is fixedly connected to the bottom of the connecting cavity;

[0007] A cleaning assembly is provided in the tank body, and the cleaning assembly includes a movable plate slidably connected to the tank body, the movable plate is penetrated with a through groove for the corresponding ceramic membrane to pass through, a cleaning sleeve is installed in the through groove, a spiral air inlet pipe extending through and extending to the outside of the tank body is fixedly connected to the movable plate, the bottom of the tank body is fixedly connected with an exhaust pipe, and a pressure control valve is installed on the exhaust pipe.

[0008] Preferably, the tank cover is fixedly installed on the top of the tank body by bolts, a sealing gasket is provided between the tank body and the tank cover, an auxiliary groove for the corresponding ceramic membrane to pass through is opened on the sealing gasket, and the bottom of the tank cover is fixedly connected to a fixing sleeve that abuts against the top of the corresponding ceramic membrane.

[0009] Preferably, the top of the placement seat is rotatably connected to a reciprocating screw threadedly connected to the movable plate, and the top of the reciprocating screw movably passes through a sealing gasket and is fixedly connected to a spline shaft, the top bolt of the tank cover is connected to a motor, and a sleeve matching the spline shaft is fixedly connected to the output shaft of the motor.

[0010] Preferably, limiting sliding blocks are symmetrically fixedly connected to both sides of the movable plate, and limiting sliding grooves slidably connected to the corresponding limiting sliding blocks are provided on the inner side wall of the tank body.

[0011] Preferably, an air intake cavity connected to the spiral air intake pipe is provided inside the movable plate, and connecting grooves are provided between the air intake cavity and the plurality of through grooves.

[0012] Preferably, an impeller is rotatably connected in the through groove, a cleaning sleeve is fixedly connected to both the top and bottom sides of the impeller, and a plurality of cleaning brushes are fixedly connected to the annular inner wall of the cleaning sleeve at equal intervals.

[0013] The present invention also provides a method for using the purge gas recovery and treatment system, comprising the following steps:

[0014] S1: The purge gas is injected into the intake cavity in the movable plate through the spiral intake pipe, and then diverted to the corresponding through grooves through multiple connecting grooves, and finally flows into the tank body. Combined with the pressure control valve on the exhaust pipe, the inside of the tank body is pressurized, forcing the hydrogen in the purge gas to penetrate the ceramic membrane and enter the connecting cavity in the placement seat, and then sent to the fuel gas network through the recovery pipe for use as fuel gas. The rest of the substances with larger molecular diameters in the purge gas cannot be separated by the ceramic membrane and are sent to the torch for combustion through the exhaust pipe;

[0015] S2: The motor drives the reciprocating screw to rotate by means of the connection between the spline shaft and the shaft sleeve, and the reciprocating screw drives the movable plate to move up and down reciprocatingly, and cooperates with the cleaning brush on the cleaning sleeve to clean the outer wall of the ceramic membrane to eliminate the blockage of the micropores of the ceramic membrane by macromolecular substances;

[0016] S3: When the exhaust gas enters the tank, the impeller is synchronously driven to rotate by means of the obliquely arranged connecting groove, thereby driving the multiple cleaning brushes on the cleaning sleeve to rotate circumferentially to comprehensively clean the annular outer wall of the ceramic membrane.

[0017] The beneficial effects of the present invention are as follows:

[0018] (1) When the present invention is used, the purge gas obtained after the carbonylation reaction is first injected into the tank body through the spiral air inlet pipe, and combined with the pressure control valve on the exhaust pipe, the pressure in the tank body is increased, forcing the hydrogen with a smaller molecular diameter in the purge gas to penetrate the ceramic membrane and enter the connecting cavity in the placement seat, and then the purge gas is separated and sent to the fuel gas network for use as fuel gas through the recovery pipe, and the separated purge gas is then sent to the torch for combustion through the exhaust pipe, thereby realizing the secondary utilization of waste gas recovery, reducing a large amount of energy waste, and achieving the effect of energy recovery and utilization;

[0019] (2) In the process of separating hydrogen from the purge gas of the present invention, the motor is combined with the reciprocating screw to drive the movable plate to move up and down, and cooperates with the cleaning brush on the cleaning sleeve to clean the macromolecular substances blocked on the micropores of the outer wall of the ceramic membrane. In this process, when the purge gas is injected into the tank body through the obliquely arranged connecting groove, the corresponding impeller is synchronously driven to rotate by the airflow power, thereby driving the multiple cleaning brushes on the cleaning sleeve to rotate circumferentially, forming an all-round cleaning coverage, achieving comprehensive cleaning of the micropores of the ceramic membrane, ensuring the continuous stability of the hydrogen separation efficiency, and laying a solid foundation for long-term and efficient energy recovery and utilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention will be further described below in conjunction with the accompanying drawings;

[0021] Figure 1 It is a schematic diagram of the structure of the present invention;

[0022] Figure 2 It is a schematic diagram of the internal structure of the tank body of the present invention;

[0023] Figure 3 It is a structural schematic diagram of the can cover of the present invention;

[0024] Figure 4 It is a structural schematic diagram of the placement seat of the present invention;

[0025] Figure 5 It is a schematic diagram of the disassembly of the reciprocating screw rod and the motor of the present invention;

[0026] Figure 6 is a schematic diagram of the structure of the cleaning component of the present invention;

[0027] Figure 7 It is a structural schematic diagram of the impeller of the present invention.

[0028] Legend:

[0029] 1. Tank body; 11. Tank cover; 12. Exhaust pipe; 13. Pressure control valve; 14. Sealing gasket; 15. Auxiliary groove; 16. Fixed sleeve; 17. Motor; 18. Shaft sleeve; 19. Limiting slide groove;

[0030] 2. Placement seat; 21. Ceramic membrane; 22. Mounting groove; 23. Communication cavity; 24. Recovery pipe; 25. Reciprocating screw rod; 26. Spline shaft;

[0031] 3. Cleaning assembly; 31. Movable plate; 32. Through groove; 33. Cleaning sleeve; 34. Spiral air inlet pipe; 35. Limiting slider; 36. Air inlet cavity; 37. Connecting groove; 38. Impeller; 39. Cleaning brush. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] Embodiment 1: The conventional separation and side reaction recovery and treatment system cannot effectively and fully reuse the hydrogen rich in the purge gas, resulting in unnecessary energy waste. This problem can be solved by the following solution:

[0034] See also Figure 1-Figure 6 As shown, a purge gas recovery and processing system in this embodiment includes a tank body 1, a tank cover 11 is installed on the top of the tank body 1, and a placement seat 2 is fixedly connected to the inside of the tank body 1, and a plurality of ceramic membranes 21 are installed between the placement seat 2 and the tank cover 11. Small molecules of hydrogen can penetrate through the micropores of the ceramic membrane 21 in the tank body 1, while other macromolecules in the purge gas cannot penetrate, thereby achieving hydrogen separation, and the plurality of ceramic membranes 21 cooperate together to improve the separation efficiency of the purge gas;

[0035] After the tank cover 11 is connected to the tank body 1, multiple ceramic membranes 21 are fixed simultaneously. A mounting groove 22 for plugging with the corresponding ceramic membrane 21 is opened on the top of the placement seat 2. The mounting groove 22 is a conical boss structure. After the ceramic membrane 21 is fixed, the connection sealing between the bottom of the ceramic membrane 21 and the placement seat 2 can be increased, thereby ensuring the high purity of hydrogen after separation and avoiding the problem that part of the hydrogen in the ceramic membrane 21 cannot be discharged;

[0036] A connecting cavity 23 connected to a plurality of mounting grooves 22 is provided inside the placement seat 2. A recovery pipe 24 penetrating to the outside of the tank body 1 is fixedly connected to the bottom of the connecting cavity 23. The hydrogen in the vented gas penetrates the ceramic membrane 21 and enters the connecting cavity 23 in the placement seat 2 through the corresponding mounting groove 22. The hydrogen is then separated and sent to the fuel gas network for use as fuel gas through the recovery pipe 24, thereby realizing the secondary utilization of waste gas recovery, reducing a large amount of energy waste, and achieving the effect of energy recycling.

[0037] A cleaning assembly 3 is provided in the tank body 1, and the cleaning assembly 3 includes a movable plate 31 slidably connected to the tank body 1, a through groove 32 for the corresponding ceramic membrane 21 to pass through is opened on the movable plate 31, a cleaning sleeve 33 is installed in the through groove 32, and a spiral air inlet pipe 34 extending through and extending to the outside of the tank body 1 is fixedly connected to the movable plate 31. The bottom of the tank body 1 is fixedly connected to an exhaust pipe 12, and a pressure control valve 13 is installed on the exhaust pipe 12. The vented gas obtained after the carbonylation reaction and treatment is injected into the tank body 1 through the spiral air inlet pipe 34, and cooperates with the pressure control valve 13 on the exhaust pipe 12 to increase the air pressure in the tank body 1 and then be discharged through the exhaust pipe 12, and through the pressure-free state inside the ceramic membrane 21, the hydrogen is forced to penetrate the ceramic membrane 21 first and be discharged through the recovery pipe 24, thereby realizing the separation and recovery of hydrogen.

[0038] The tank cover 11 is fixedly installed on the top of the tank body 1 by bolts. The detachable connection between the tank cover 11 and the tank body 1 can replace the ceramic membrane 21 that has been used for a long time. A sealing gasket 14 is provided between the tank body 1 and the tank cover 11, so that the sealing between the tank cover 11 and the tank body 1 is increased after the connection between the two. The sealing gasket 14 is provided with a through hole corresponding to the bolts used to connect the tank cover 11 and the tank body 1, thereby increasing the anti-deflection effect of the sealing gasket 14 placed on the tank body 1. The sealing gasket 14 is provided with an auxiliary groove 15 for the corresponding ceramic membrane 21 to pass through.

[0039] By means of the auxiliary groove 15 opened on the sealing gasket 14 and the corresponding installation groove 22, the vertical stability of the ceramic membrane 21 can be increased after the ceramic membrane 21 is plugged into the placement seat 2, thereby achieving stable fixation of the ceramic membrane 21 after the tank cover 11 is connected to the tank body 1. The bottom of the tank cover 11 is fixedly connected with a fixing sleeve 16 that abuts against the top of the corresponding ceramic membrane 21. The fixing sleeve 16 is made of an anti-corrosion elastic material, so that after the tank cover 11 is connected to the tank body 1, the top of the ceramic membrane 21 is abutted through the fixing sleeve 16, so that one end of the ceramic membrane 21 is closed while the ceramic membrane 21 is not excessively squeezed and damaged.

[0040] Embodiment 2: The problem that the micropores of the ceramic membrane are easily blocked by macromolecular substances, thereby reducing the hydrogen separation efficiency, can be solved by the following solution:

[0041] See also Figure 6 and Figure 7As shown, in this embodiment, a cleaning component 3 is provided in the tank body 1, and the cleaning component 3 includes a movable plate 31 slidably connected in the tank body 1, and a through groove 32 for the corresponding ceramic membrane 21 to pass through is opened on the movable plate 31, and a cleaning sleeve 33 is installed in the through groove 32. In the process of multiple ceramic membranes 21 separating hydrogen in the exhaust gas, the movable plate 31 reciprocates and rises and falls in the tank body 1, driving the cleaning sleeve 33 to slide on the outside of the corresponding ceramic membrane 21, and cleaning the macromolecular substances blocked on the micropores on the outer wall of the ceramic membrane 21, so as to avoid reducing the separation efficiency of hydrogen. A spiral air inlet pipe 34 is fixedly connected to the movable plate 31 and extends to the outside of the tank body 1.

[0042] The top of the placement seat 2 is rotatably connected to a reciprocating screw 25 threadedly connected to the movable plate 31, and the top of the reciprocating screw 25 movably penetrates the sealing gasket 14 and is fixedly connected to a spline shaft 26. The top bolt of the tank cover 11 is connected to a motor 17, and a sleeve 18 matched with the spline shaft 26 is fixedly connected to the output shaft of the motor 17. The motor 17 drives the reciprocating screw 25 to rotate through the cooperation of the sleeve 18 and the spline shaft 26. The reciprocating screw 25 realizes the lifting and lowering movement of the movable plate 31, and through the cooperation of the sleeve 18 and the spline shaft 26, it will not interfere with the disassembly between the tank cover 11 and the tank body 1.

[0043] The movable plate 31 is symmetrically fixedly connected to the limiting sliders 35 on both sides, and the inner wall of the tank body 1 is provided with a limiting slide groove 19 which is slidably connected to the corresponding limiting slider 35. The limiting slider 35 cooperates with the limiting slide groove 19 to prevent the movable plate 31 from deflecting following the rotation of the reciprocating screw 25, thereby increasing the contact force between the cleaning sleeve 33 and the ceramic membrane 21, avoiding damage to the ceramic membrane 21 and affecting the rotation of the cleaning sleeve 33.

[0044] An air intake cavity 36 connected to the spiral air intake pipe 34 is provided inside the movable plate 31, and connecting grooves 37 are provided between the air intake cavity 36 and the multiple through grooves 32. The relief air in the spiral air intake pipe 34 first enters the air intake cavity 36, and then enters the corresponding through grooves 32 through the multiple connecting grooves 37, and then enters the tank body 1. The spiral shape of the spiral air intake pipe 34 can avoid interference with the lifting and lowering movement of the movable plate 31 and the injection of relief air. A receiving groove is provided on the top of the placement seat 2 just below the spiral air intake pipe 34 to prevent the movable plate 31 from descending to the lowest point and excessively squeezing the spiral air intake pipe 34, thereby causing discontinuity in the relief air separation process. The connecting grooves 37 are arranged obliquely to change the airflow direction of the relief air entering the through grooves 32.

[0045] An impeller 38 is rotatably connected in the through groove 32, and a cleaning sleeve 33 is fixedly connected to both the top and bottom sides of the impeller 38. A plurality of cleaning brushes 39 are equidistantly fixedly connected to the annular inner wall of the cleaning sleeve 33. When the exhaust gas is injected into the corresponding through groove 32 through the obliquely arranged connecting groove 37, the corresponding impeller 38 is driven to rotate by the airflow force, thereby driving the plurality of cleaning brushes 39 on the cleaning sleeve 33 to rotate circumferentially, and cooperate with the lifting and lowering movement of the cleaning sleeve 33 to form an all-round cleaning coverage of the ceramic membrane 21, thereby achieving comprehensive cleaning of the micropores of the ceramic membrane 21, ensuring the continuous stability of the hydrogen separation efficiency, and laying a solid foundation for long-term and efficient energy recovery and utilization.

[0046] Example 3: Please refer to Figure 1-Figure 7 As shown, the present invention also provides a method for using the purge gas recovery and treatment system, comprising the following steps:

[0047] S1: The purge gas is injected into the intake cavity 36 in the movable plate 31 through the spiral intake pipe 34, and then diverted to the corresponding through grooves 32 through multiple connecting grooves 37, and finally flows into the interior of the tank body 1, and combined with the pressure control valve 13 on the exhaust pipe 12, the interior of the tank body 1 is pressurized, forcing the hydrogen in the purge gas to penetrate the ceramic membrane 21 and enter the connecting cavity 23 in the placement seat 2, and then sent to the fuel gas network through the recovery pipe 24 for use as fuel gas. The remaining substances with larger molecular diameters in the purge gas cannot be separated by the ceramic membrane 21 and are sent to the torch for combustion through the exhaust pipe 12;

[0048] S2: The motor 17 drives the reciprocating screw 25 to rotate by means of the connection between the spline shaft 26 and the sleeve 18, and the reciprocating screw 25 drives the movable plate 31 to move up and down, and cooperates with the cleaning brush 39 on the cleaning sleeve 33 to clean the outer wall of the ceramic membrane 21 to eliminate the blockage of the micropores of the ceramic membrane 21 by macromolecular substances;

[0049] S3: When the purge gas enters the tank body 1 , the impeller 38 is synchronously driven to rotate by means of the obliquely arranged connecting groove 37 , thereby driving the multiple cleaning brushes 39 on the cleaning sleeve 33 to rotate circumferentially, thereby comprehensively cleaning the annular outer wall of the ceramic membrane 21 .

[0050] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A purge gas recovery and treatment system, comprising a tank body (1), a tank cover (11) being installed on the top of the tank body (1), and a placement seat (2) being fixedly connected to the inside of the tank body (1), characterized in that: A plurality of ceramic membranes (21) are installed between the placement seat (2) and the tank cover (11); a mounting groove (22) for plugging into corresponding ceramic membranes (21) is provided on the top of the placement seat (2); a connecting cavity (23) communicating with the plurality of mounting grooves (22) is provided inside the placement seat (2); a recovery pipe (24) penetrating to the outside of the tank body (1) is fixedly connected to the bottom of the connecting cavity (23); A cleaning assembly (3) is arranged in the tank body (1), and the cleaning assembly (3) comprises a movable plate (31) slidably connected in the tank body (1), a through groove (32) is penetrated through the movable plate (31) for the corresponding ceramic membrane (21) to pass through, a cleaning sleeve (33) is installed in the through groove (32), a spiral air inlet pipe (34) is fixedly connected to the movable plate (31) and extends through the outside of the tank body (1), the bottom of the tank body (1) is fixedly connected to an exhaust pipe (12), and a pressure control valve (13) is installed on the exhaust pipe (12).

2. A purge gas recovery and treatment system according to claim 1, characterized in that: The tank cover (11) is fixedly mounted on the top of the tank body (1) by means of bolts, a sealing gasket (14) is provided between the tank body (1) and the tank cover (11), an auxiliary groove (15) is provided on the sealing gasket (14) for the corresponding ceramic membrane (21) to pass through, and a fixing sleeve (16) is fixedly connected to the bottom of the tank cover (11) and abuts against the top of the corresponding ceramic membrane (21).

3. A purge gas recovery and treatment system according to claim 2, characterized in that: The top of the placement seat (2) is rotatably connected to a reciprocating screw (25) threadedly connected to the movable plate (31), and the top of the reciprocating screw (25) movably penetrates the sealing gasket (14) and is fixedly connected to a spline shaft (26). The top of the tank cover (11) is bolted to a motor (17), and a shaft sleeve (18) adapted to the spline shaft (26) is fixedly connected to the output shaft of the motor (17).

4. A purge gas recovery and treatment system according to claim 1, characterized in that: Limiting slide blocks (35) are symmetrically fixedly connected to both sides of the movable plate (31), and limiting sliding grooves (19) slidably connected to corresponding limiting slide blocks (35) are provided on the inner side wall of the tank body (1).

5. The purge gas recovery and treatment system according to claim 1, characterized in that: An air intake cavity (36) communicating with the spiral air intake pipe (34) is provided inside the movable plate (31), and connecting grooves (37) are provided between the air intake cavity (36) and the plurality of through grooves (32).

6. A purge gas recovery and treatment system according to claim 1, characterized in that: An impeller (38) is rotatably connected in the through groove (32), a cleaning sleeve (33) is fixedly connected to both the top and bottom sides of the impeller (38), and a plurality of cleaning brushes (39) are fixedly connected to the annular inner wall of the cleaning sleeve (33) at equal intervals.

7. A method for using a purge gas recovery and treatment system, used for a purge gas recovery and treatment system as claimed in any one of claims 1 to 6, characterized in that: The following steps are involved: S1: The purge gas is injected into the intake cavity (36) in the movable plate (31) through the spiral intake pipe (34), and then is diverted to the corresponding through grooves (32) through a plurality of connecting grooves (37), and finally flows into the interior of the tank body (1). In combination with the pressure control valve (13) on the exhaust pipe (12), the interior of the tank body (1) is pressurized, forcing the hydrogen in the purge gas to penetrate the ceramic membrane (21) and enter the connecting cavity (23) in the placement seat (2), and then is sent to the fuel gas network through the recovery pipe (24) for use as fuel gas. The remaining substances with larger molecular diameters in the purge gas cannot be separated by the ceramic membrane (21) and are sent to the flare for combustion through the exhaust pipe (12); S2: The motor (17) drives the reciprocating screw (25) to rotate by means of the connection between the spline shaft (26) and the shaft sleeve (18), and the reciprocating screw (25) drives the movable plate (31) to move up and down, and cooperates with the cleaning brush (39) on the cleaning sleeve (33) to clean the outer wall of the ceramic membrane (21) to eliminate the blockage of the micropores of the ceramic membrane (21) by macromolecular substances; S3: When the purge gas enters the tank body (1), the obliquely arranged connecting groove (37) is used to synchronously push the impeller (38) to rotate, thereby driving the plurality of cleaning brushes (39) on the cleaning sleeve (33) to rotate circumferentially, thereby comprehensively cleaning the annular outer wall of the ceramic membrane (21).

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