Acetylene buffer system under vinyl pyrrolidone production accident
By designing acetylene buffer system, using acetylene compressor and acetylene recovery tank to achieve acetylene recovery and buffer in the state of accident, solve the problem of acetaidal waste and lack of buffer time in the accident when the ethylene reactor is stopped. Process safety and production continuity.
Patent Information
- Application Number
- CN202420919754.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-29
- Publication Date
- 2025-01-24
- Estimated Expiration
- 2034-04-29
AI Technical Summary
When the ethylene reactor is turned on and stopped, the acetylene gas in the system is not recycled, resulting in waste; in the accident state, the acetylene gas and propane gas reach the pipe burst limit, lacking buffer time, which may cause a major accident.
An acetylene buffer system is designed, including an acetylene buffer tank, a flash tank and an ethylene reactor. The acetylene compressor boosts the pressure and sends the gas to the acetylene recovery tank for temporary storage. When the system is started again, it is discharged to the acetylene through the regulating valve. The buffer tank is reused and an acetylene recovery tank is used for buffering in the event of an accident.
The recycling and utilization of acetylene gas has been achieved, a lot of acetylene is saved, and the qi buffer is provided in the state of the accident, reducing the occurrence of safety accidents, and ensuring the continuity of the production device.
Smart Images
Figure CN222384790U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of vinyl pyrrolidone production, in particular to an acetylene buffer system for accidents in the production of vinyl pyrrolidone. Background Art
[0002] NVP synthesis belongs to a medium-pressure reaction system. Acetylene and propane are used as a mixture in the reaction process. The system has the risk of overpressure, and the material is thermally unstable. After the system thermal runaway and overheating, it is easy to cause secondary decomposition of the material. The decomposition process releases heat and is accompanied by gas release. There is a risk of secondary decomposition caused by overtemperature, which leads to the risk of overpressure in the system. Although the system pressure is controlled by feed, pressure, temperature interlock automatic control and other methods at key nodes in the reactor to avoid and control the reaction risk, the equipment is installed with safety relief devices, such as safety valves and bursting discs, to avoid safety accidents caused by system overpressure.
[0003] However, every time the ethylene reactor was started and stopped, the acetylene gas in the system was not recycled, thus wasting a large amount of acetylene gas; when the ethylene reactor was overpressured or in an accident state, the acetylene gas and propane gas would instantly reach the burst limit, and the system pipeline did not have enough buffer time, resulting in major accidents. Moreover, once the source of acetylene gas fluctuated, it would affect the start-up and shutdown of the device, seriously affecting the continuity of production. Utility Model Content
[0004] The utility model aims to provide an acetylene buffer system for producing vinyl pyrrolidone under accident conditions, which can avoid the situation in which the acetylene gas in the system is not recycled when the ethylene reactor is started or stopped, thereby wasting a large amount of acetylene gas.
[0005] The utility model provides an acetylene buffer system for producing vinyl pyrrolidone under accidents, comprising an acetylene buffer tank, a flash tank and an ethylene reactor, a connecting pipe is arranged at the gas outlet end of the acetylene buffer tank, the gas outlet end of the connecting pipe is connected with the gas inlet pipe at one side of an acetylene recovery tank, acetylene gas and propane gas transported from the outside and acetylene gas discharged from the flash tank and the ethylene reactor are transported to the acetylene buffer tank by a regulating valve, and the gas in the acetylene buffer tank is transported to the acetylene recovery tank for temporary storage by an acetylene compressor.
[0006] In a specific embodiment, safety valves are provided on both the acetylene recovery tank and the acetylene buffer tank.
[0007] In a specific embodiment, the temperature of the ethylene reactor is controlled by a reactor heat exchanger and a circulating gas cooler, and the gas phase of the ethylene reactor enters the acetylene buffer tank as circulating gas and participates in the reaction through an acetylene compressor.
[0008] In a specific embodiment, the liquid phase produced by the ethylene reactor enters a flash tank for flash evaporation, the gas phase flashed by the flash tank enters an acetylene buffer tank for reuse, and the liquid phase flashed by the flash tank enters a subsequent process section through a flash tank transfer pump.
[0009] In a specific embodiment, a first sealing cover is slidably arranged on the air intake pipe, a sealing groove is provided on one side of the first sealing cover, a second sealing cover is slidably arranged on the connecting pipe, a sealing strip is provided on one side of the second sealing cover, and the sealing strip is clamped in the sealing groove.
[0010] In a specific embodiment, the first sealing cover is fixed by a first fixing sleeve, and the second sealing cover is fixed by a second fixing sleeve, and grooves are provided inside the first fixing sleeve and the second fixing sleeve.
[0011] In a specific embodiment, a gear ring is rotatably arranged on the outer side of the second sealing cover, and the gear ring is meshed with a driving wheel rotatably arranged on the lower side of the second sealing cover, and the driving wheel is driven by a micro motor.
[0012] In a specific embodiment, a connecting rod is provided on one side of the gear ring, a base is provided at one end of the connecting rod, an adjusting plate is hingedly connected to the upper side of the base, and a gas sensor is installed on the adjusting plate.
[0013] In a specific embodiment, an annular edge is arranged on the inner side of the gear ring, and the annular edge is rotatably arranged in an annular groove opened on the outer side of the second sealing cover.
[0014] In a specific implementation, a first valve is installed on the connecting pipe, and a second valve is installed on the air intake pipe.
[0015] The embodiment of the utility model provides an acetylene buffer system for producing vinyl pyrrolidone under accident conditions, compared with the prior art:
[0016] 1. The utility model increases the pressure of the acetylene compressor and then sends the gas to the acetylene recovery tank for temporary storage. When the system is started again, the acetylene gas temporarily stored in the recovery tank is discharged to the acetylene buffer tank by the regulating valve and returned to the system for reuse, thereby providing a safeguard for the process safety of the acetylene gas, realizing the recycling of the acetylene gas during start-up and shutdown, saving a large amount of acetylene gas, and in an accident state, the gaseous acetylene gas and propane gas can first enter the acetylene recovery tank to play a buffering role, and can still be recycled later. Secondly, when the acetylene gas transported from an external plant is temporarily abnormal, the material in the acetylene recovery tank can be used to maintain a short-term production to ensure the continuity of the production device.
[0017] 2. The utility model seals the connection between the connecting pipe and the air intake pipe through the first sealing cover and the second sealing cover, thereby effectively preventing gas leakage. At the same time, through the meshing of the gear ring and the driving wheel, the gear ring carries the gas sensor to rotate at the connection between the first sealing cover and the second sealing cover, and gas sensing is performed in real time, which can quickly detect gas leakage and reduce the occurrence of safety accidents. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] In order to more clearly illustrate the technical solution of the implementation mode of the utility model, the drawings required for use in the implementation mode will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.
[0019] Figure 1 A schematic diagram of the process flow of the overall structure of an embodiment of the utility model;
[0020] Figure 2 This is a schematic diagram of the structure of an acetylene recovery tank according to an embodiment of the utility model;
[0021] Figure 3 This is a schematic diagram of the disassembly of the first sealing cover and the second sealing cover structure of an embodiment of the utility model;
[0022] Figure 4 This is a schematic diagram of the disassembled structure of the gear ring and the second sealing cover of an embodiment of the utility model;
[0023] Figure 5 This is a schematic diagram of the gas sensor structure installation according to an embodiment of the utility model.
[0024] icon:
[0025] 1. Acetylene buffer tank; 2. Flash tank; 3. Flash tank delivery pump; 4. Ethylene reactor; 5. Acetylene compressor; 6. Reactor heat exchanger; 7. Circulating gas cooler; 8. Regulating valve; 9. Acetylene recovery tank; 10. Inlet pipe; 11. Connecting pipe; 12. First valve; 13. Second valve; 14. First sealing cover; 15. First fixing sleeve; 16. Sealing groove; 17. Second sealing cover; 18. Second fixing sleeve; 181. Groove; 19. Annular groove; 20. Sealing strip; 21. Gear ring; 22. Annular edge; 23. Driving wheel; 24. Micro motor; 25. Connecting rod; 26. Base; 27. Adjusting plate; 28. Gas sensor. DETAILED DESCRIPTION
[0026] Every time the ethylene reactor is started and stopped, the acetylene gas in the system is not recycled, thus wasting a large amount of acetylene gas; when the ethylene reactor is overpressured or in an accident state, the acetylene gas and propane gas will instantly reach the burst limit, and the system pipeline does not have enough buffer time, resulting in major accidents. In addition, once the source of acetylene gas fluctuates, it will affect the start-up and shutdown of the device, seriously affecting the continuity of production. Therefore, after research, an acetylene buffer system for producing vinyl pyrrolidone under accident conditions is provided. When in use, the gas is pressurized by an acetylene compressor and then sent to an acetylene recovery tank for temporary storage. The acetylene gas temporarily stored in the recovery tank is discharged to the acetylene buffer tank by a regulating valve when the system is started again and returns to the system for reuse, thereby providing a safeguard for the process safety of the acetylene gas and realizing the recovery and utilization of the acetylene gas during start-up and shutdown, saving a large amount of acetylene gas. Moreover, in an accident state, the gaseous acetylene gas and propane gas can first enter the acetylene recovery tank to play a buffering role and can still be recycled later. Secondly, when the acetylene gas transported from an external plant is temporarily abnormal, the material in the acetylene recovery tank can be used to maintain production for a short time to ensure the continuity of the production device, thereby solving the above-mentioned defects.
[0027] In conjunction with the accompanying drawings, some embodiments of the present invention are described in detail below. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.
[0028] Please refer to Figure 1-Figure 5 The embodiment of the utility model provides an acetylene buffer system for producing vinyl pyrrolidone under accident conditions, including an acetylene buffer tank 1, a flash tank 2 and an ethylene reactor 4. A connecting pipe 11 is provided at the gas outlet end of the acetylene buffer tank 1, and the gas outlet end of the connecting pipe 11 is connected to an air inlet pipe 10 on one side of an acetylene recovery tank 9.
[0029] The acetylene gas and propane gas transported from the outside and the acetylene gas discharged from the flash tank 2 and the ethylene reactor 4 are transported to the acetylene buffer tank 1 by the regulating valve 8. The gas in the acetylene buffer tank 1 is transported to the acetylene recovery tank 9 for temporary storage through the acetylene compressor 5. The acetylene gas temporarily stored in the acetylene recovery tank 9 is discharged to the acetylene buffer tank 1 by the regulating valve 8 when the system is started again, and returns to the system for reuse, thereby providing a safeguard for the process safety of the acetylene gas.
[0030] Safety valves are provided on the acetylene recovery tank 9 and the acetylene buffer tank 1, which are discharged to the flare system when overpressure occurs. The temperature of the ethylene reactor 4 is controlled by the reactor heat exchanger 6 and the circulating gas cooler 7. The gas phase of the ethylene reactor 4 enters the acetylene buffer tank 1 as circulating gas, and participates in the reaction through the acetylene compressor 5. The liquid phase produced by the ethylene reactor 4 enters the flash tank 2 for flash evaporation. The gas phase flashed by the flash tank 2 enters the acetylene buffer tank 1 for reuse, and the liquid phase flashed by the flash tank 2 enters the subsequent process section through the flash tank transfer pump 3.
[0031] Among them, in order to avoid gas leakage when the gas is transported to the acetylene recovery tank 9, a first sealing cover 14 is slidably arranged on the intake pipe 10, and a sealing groove 16 is opened on one side of the first sealing cover 14. A second sealing cover 17 is slidably arranged on the connecting pipe 11, and a sealing strip 20 is arranged on one side of the second sealing cover 17. The sealing strip 20 is clamped in the sealing groove 16. The connection between the connecting pipe 11 and the intake pipe 10 is sealed by the first sealing cover 14 and the second sealing cover 17. At the same time, the sealing strip 20 is used to enhance the sealing effect. The sealing strip 20 can be made of silicone rubber with good sealing properties.
[0032] The first sealing cover 14 is fixed by the first fixing sleeve 15, and the second sealing cover 17 is fixed by the second fixing sleeve 18. A groove 181 is provided inside the first fixing sleeve 15 and the second fixing sleeve 18. One end of the first sealing cover 14 and the second sealing cover 17 can be located in the groove 181 for fixing. The first fixing sleeve 15 and the second fixing sleeve 18 are fixed by bolts.
[0033] Furthermore, a gear ring 21 is rotatably provided on the outer side of the second sealing cover 17, and the gear ring 21 meshes with a driving wheel 23 rotatably provided on the lower side of the second sealing cover 17. The driving wheel 23 is driven by a micro motor 24. When the driving wheel 23 is driven to rotate by the micro motor 24, the gear ring 21 rotates by meshing with the driving wheel 23.
[0034] A connecting rod 25 is arranged on one side of the gear ring 21, a base 26 is arranged on one end of the connecting rod 25, an adjusting plate 27 is hinged on the upper side of the base 26, the adjusting plate 27 is rotated to be parallel to the second sealing cover 17, a gas sensor 28 is installed on the adjusting plate 27, when the gear ring 21 rotates, the gas sensor 28 is driven to rotate, the gas sensor 28 can use an acetylene gas sensor to sense the leaked gas, and the gas sensor 28 senses around the connection between the first sealing cover 14 and the second sealing cover 17, so that workers can find gas leakage in time and reduce safety hazards.
[0035] An annular edge 22 is disposed on the inner side of the gear ring 21 , and the annular edge 22 is rotatably disposed in an annular groove 19 provided on the outer side of the second sealing cover 17 , so as to improve the stability of the gear ring 21 during rotation.
[0036] It is worth noting that a first valve 12 is installed on the connecting pipe 11 and a second valve 13 is installed on the air intake pipe 10. After gas leakage, the first valve 12 and the second valve 13 are closed to prevent continuous gas delivery.
[0037] In summary, the acetylene buffer system for producing vinyl pyrrolidone under accident conditions in the embodiment of the utility model has the following working principles: the acetylene gas and propane gas transported from the outside and the acetylene gas discharged from the flash tank 2 and the ethylene reactor 4 are sent to the acetylene buffer tank 1 by the regulating valve 8, and are sent to the acetylene recovery tank 9 for temporary storage after being pressurized by the acetylene compressor 5. The acetylene gas temporarily stored in the acetylene recovery tank 9 is discharged to the acetylene buffer tank 1 by the regulating valve 8 when the system is started again, and is returned to the system for reuse, so as to provide a safeguard for the process safety of the acetylene gas. Safety valves are arranged on the acetylene recovery tank 9 and the acetylene buffer tank 1, and are discharged to the flare system when overpressure occurs. The temperature of the ethylene reactor 4 is controlled by the reactor heat exchanger 6. The temperature is controlled, the gas phase of the ethylene reactor 4 enters the acetylene buffer tank 1 as the circulating gas, and then participates in the reaction through the acetylene compressor 5, the liquid phase of the ethylene reactor 4 enters the flash tank 2 for flash evaporation, the flashed gas phase enters the acetylene buffer tank 1 for repeated use, and the liquid phase enters the subsequent section through the flash tank delivery pump 3. At the same time, the first sealing cover 14 and the second sealing cover 17 seal the connection between the connecting pipe 11 and the air intake pipe 10, effectively preventing gas leakage. At the same time, through the meshing of the gear ring 21 and the driving wheel 23, the gear ring 21 rotates with the gas sensor 28 at the connection between the first sealing cover 14 and the second sealing cover 17, and gas sensing is performed in real time.
[0038] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may be subject to various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.
Claims
1. An acetylene buffer system for producing vinyl pyrrolidone under accident conditions, comprising an acetylene buffer tank (1), a flash tank (2) and a vinylation reactor (4), characterized in that: A connecting pipe (11) is provided at the gas outlet end of the acetylene buffer tank (1), and the gas outlet end of the connecting pipe (11) is connected to a gas inlet pipe (10) on one side of an acetylene recovery tank (9). Acetylene gas and propane gas transported from the outside and acetylene gas discharged from a flash tank (2) and an ethylene reactor (4) are transported to the acetylene buffer tank (1) through a regulating valve (8), and the gas in the acetylene buffer tank (1) is transported to the acetylene recovery tank (9) for temporary storage through an acetylene compressor (5).
2. The acetylene buffer system for producing vinyl pyrrolidone under accident conditions according to claim 1, characterized in that: The acetylene recovery tank (9) and the acetylene buffer tank (1) are both provided with safety valves.
3. The acetylene buffer system for producing vinyl pyrrolidone under accident conditions according to claim 2, characterized in that: The temperature of the ethylene reactor (4) is controlled by a reactor heat exchanger (6) and a circulating gas cooler (7). The gas phase of the ethylene reactor (4) enters the acetylene buffer tank (1) as circulating gas and participates in the reaction through an acetylene compressor (5).
4. The acetylene buffer system for producing vinyl pyrrolidone under accident conditions according to claim 3, characterized in that: The liquid phase generated by the ethylene reactor (4) enters the flash tank (2) for flash evaporation, the gas phase flashed by the flash tank (2) enters the acetylene buffer tank (1) for reuse, and the liquid phase flashed by the flash tank (2) enters the subsequent process section through the flash tank delivery pump (3).
5. The acetylene buffer system for producing vinyl pyrrolidone under accident conditions according to claim 1, characterized in that: A first sealing cover (14) is slidably arranged on the air intake pipe (10), a sealing groove (16) is provided on one side of the first sealing cover (14), a second sealing cover (17) is slidably arranged on the connecting pipe (11), a sealing strip (20) is provided on one side of the second sealing cover (17), and the sealing strip (20) is snap-fitted into the sealing groove (16).
6. The acetylene buffer system for producing vinyl pyrrolidone under accident conditions according to claim 5, characterized in that: The first sealing cover (14) is fixed by a first fixing sleeve (15), and the second sealing cover (17) is fixed by a second fixing sleeve (18). Grooves (181) are provided inside the first fixing sleeve (15) and the second fixing sleeve (18).
7. The acetylene buffer system for producing vinyl pyrrolidone under accident conditions according to claim 6, characterized in that: A gear ring (21) is rotatably arranged on the outer side of the second sealing cover (17), and the gear ring (21) is meshed with a driving wheel (23) rotatably arranged on the lower side of the second sealing cover (17), and the driving wheel (23) is driven by a micro motor (24).
8. The acetylene buffer system for producing vinyl pyrrolidone under accident conditions according to claim 7, characterized in that: A connecting rod (25) is arranged on one side of the gear ring (21), a base (26) is arranged on one end of the connecting rod (25), an adjustment plate (27) is hingedly connected to the upper side of the base (26), and a gas sensor (28) is installed on the adjustment plate (27).
9. The acetylene buffer system for producing vinyl pyrrolidone under accident conditions according to claim 8, characterized in that: An annular edge (22) is arranged on the inner side of the gear ring (21), and the annular edge (22) is rotatably arranged in an annular groove (19) provided on the outer side of the second sealing cover (17).
10. The acetylene buffer system for producing vinyl pyrrolidone under accident conditions according to claim 1, characterized in that: A first valve (12) is installed on the connecting pipe (11), and a second valve (13) is installed on the air intake pipe (10).