Acrylonitrile cracking reaction protection device

Abstract

The utility model relates to the technical field of acrylonitrile cracking, in particular to an acrylonitrile cracking reaction protection device. The acrylonitrile cracking reaction protection device comprises a reactor, the reactor is connected with a neutralizing tower through a pipeline, a reactor jacket layer is arranged on the outer side of the reactor, a spraying disc is arranged in the neutralizing tower, the neutralizing tower is connected with a liquid phase temporary storage tank through an active heat exchanger, and the liquid phase temporary storage tank is connected with the spraying disc through a spraying water storage tank. And the reactor is connected with a gas temporary storage tank through an induced draft fan. According to the device, through the arrangement of the active heat exchanger, the liquid phase temporary storage tank and the emergency pump, during emergency shutdown, the emergency pump is rapidly started, the cooling water amount is increased, the reactor and the neutralizing tower are cooled, and danger caused by too slow cooling is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of acrylonitrile cracking, in particular to an acrylonitrile cracking reaction protection device. Background Art

[0002] Acrylonitrile (C3H3N) is an important organic chemical widely used in the production of synthetic fibers, synthetic rubber, plastics and other fields. Acrylonitrile is mainly synthesized by propylene ammoxidation, which reacts propylene and ammonia to produce acrylonitrile under high temperature, high pressure and catalyst conditions. However, in the synthesis process of acrylonitrile, due to the harsh reaction conditions, there are certain safety risks.

[0003] In existing production, when emergency shutdown is required, the reactor and neutralization tower are mainly protected by adding interlocking devices, but the cooling effect is not obvious, and the gas in the device is not discharged in time after the interlocking is closed.

[0004] Chinese patent application CN216260691U was published on April 12, 2022. A safety protection system for an acrylonitrile reactor is disclosed, including an ammonia feed line, a propylene feed line, an air feed line, an accident nitrogen line, a reactor, a quench neutralization tower and a quench aftercooler, and an ammonia flowmeter, an ammonia feed regulating valve, a propylene flowmeter, a propylene feed regulating valve, an air flowmeter and an air feed regulating valve are connected; the lower liquid level gauge and the upper liquid level gauge of the quench neutralization tower are respectively connected to the lower water supply regulating valve, the upper water supply regulating valve and the gas phase external delivery regulating valve and the liquid phase external delivery regulating valve on the quench aftercooler. However, during emergency shutdown, there is a problem that the cooling of the reactor and the quench neutralization tower is not obvious. Utility Model Content

[0005] In view of the above deficiencies in the prior art, the purpose of the utility model is to provide an acrylonitrile cracking reaction protection device. By setting an active heat exchanger, a liquid phase temporary storage tank and an emergency pump, in the event of an emergency stop, the emergency pump is quickly turned on to increase the amount of cooling water, and the reactor and the neutralization tower are cooled to avoid danger caused by too slow cooling; by setting an induced draft fan, a gas mixer and a gas temporary storage tank, the residual gas phase in the device is extracted and mixed with nitrogen to reduce the content of dangerous gases, thereby greatly improving the safety of the device.

[0006] The utility model is realized by adopting the following technical solutions:

[0007] The acrylonitrile cracking reaction protection device comprises a reactor, which is connected to a neutralization tower through a pipeline, a reactor jacket is arranged on the outside of the reactor, a spray plate is arranged inside the neutralization tower, the neutralization tower is connected to a liquid phase temporary storage tank through an active heat exchanger, the liquid phase temporary storage tank is connected to the spray plate through a spray water storage tank, and the reactor is connected to a gas temporary storage tank through an induced draft fan.

[0008] The reactor jacket plays a certain role in heat preservation during normal production. In case of emergency shutdown, the emergency pump quickly pumps cooling water into the reactor jacket to cool the reactor. The liquid phase temporary storage tank and emergency pump play a role in backup emergency.

[0009] The reactor is connected with a connecting pipe, and the connecting pipe is sequentially connected with a nitrogen pipe, a propylene feed pipe and an ammonia feed pipe. The connection between the nitrogen pipe and the connecting pipe is located at a side close to the reactor.

[0010] The reactor is connected with an air inlet pipeline and is provided with a safety air outlet.

[0011] The safety gas outlet is connected to the induced draft fan, a gas mixer is arranged between the induced draft fan and the gas temporary storage tank, and a nitrogen inlet gas mixer pipeline is arranged on the gas mixer.

[0012] The induced draft fan is used to introduce the gas phase in the reactor into the gas mixer, mix it with nitrogen to reduce the content of dangerous gases, and then enter the gas storage tank.

[0013] A circulation pipeline is arranged between the spray water storage tank and the spray plate, and the liquid phase temporary storage tank is connected to the circulation pipeline through an emergency pump.

[0014] The circulating pipeline is connected to the reactor jacket through an inlet reactor jacket pipeline, and the reactor jacket is connected with an outlet reactor jacket pipeline.

[0015] A spray water tank inlet pipeline is connected between the liquid phase temporary storage tank and the spray water tank, and the connection between the spray water tank inlet pipeline and the liquid phase temporary storage tank is close to the top of the liquid phase temporary storage tank. A certain amount of cooling water is always stored in the liquid phase temporary storage tank.

[0016] The working principle of the utility model is:

[0017] Ammonia, propylene and air enter the reactor through the ammonia feed pipeline, propylene feed pipeline and air inlet pipeline in turn to react. After the reaction is completed, they enter the neutralization tower through the pipeline, and the active heat exchanger, spray water storage tank and spray plate start working; when an emergency occurs and it is necessary to stop the vehicle, the emergency pump is quickly turned on to pump cooling water into the neutralization tower and the reactor jacket to cool the reactor and the neutralization tower; at the same time, the induced draft fan is turned on to introduce the gas phase in the reactor into the gas mixer, mix it with nitrogen, reduce the content of dangerous gases, and then enter the gas temporary storage tank. Among them, the reactor jacket plays a certain role in heat preservation for the reactor during normal production. In the event of emergency stop, the emergency pump quickly pumps cooling water into the reactor jacket to cool the reactor; the liquid phase temporary storage tank and the emergency pump play a role in standby emergency. The induced draft fan is used to introduce the gas phase in the reactor into the gas mixer, mix it with nitrogen, reduce the content of dangerous gases, and then enter the gas temporary storage tank.

[0018] Compared with the prior art, the beneficial effects of the utility model are:

[0019] The acrylonitrile cracking reaction protection device of the utility model is provided with an active heat exchanger, a liquid phase temporary storage tank and an emergency pump. When the device is shut down in an emergency, the emergency pump is quickly turned on to increase the amount of cooling water, and the reactor and the neutralization tower are cooled to avoid danger caused by too slow cooling. The residual gas phase in the device is extracted and mixed with nitrogen through the provision of an induced draft fan, a gas mixer and a gas temporary storage tank to reduce the content of dangerous gases, thereby greatly improving the safety of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the structure of the acrylonitrile cracking reaction protection device of the utility model;

[0021] In the figure: 1. Reactor; 2. Neutralization tower; 3. induced draft fan; 4. Gas mixer; 5. Gas temporary storage tank; 6. Active heat exchanger; 7. Liquid phase temporary storage tank; 8. Spray water storage tank; 9. Air inlet pipe; 10. Connecting pipe; 11. Nitrogen pipe; 12. Propylene feed pipe; 13. Ammonia feed pipe; 14. Reactor jacket; 15. Safety outlet; 16. Nitrogen inlet pipe to gas mixer; 17. Inlet pipe to spray water storage tank; 18. Spray plate; 19. Circulation pipe; 20. Emergency pump; 21. Inlet pipe to reactor jacket; 22. Outlet pipe from reactor jacket. DETAILED DESCRIPTION

[0022] In order to make the purpose and technical solution of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings.

[0023] Example 1

[0024] like Figure 1As shown, the acrylonitrile cracking reaction protection device includes a reactor 1, which is connected to a neutralization tower 2 through a pipeline, a reactor jacket 14 is provided on the outside of the reactor 1, a spray plate 18 is provided inside the neutralization tower 2, the neutralization tower 2 is connected to a liquid phase temporary storage tank 7 through an active heat exchanger 6, the liquid phase temporary storage tank 7 is connected to the spray plate 18 through a spray water storage tank 8, and the reactor 1 is connected to a gas temporary storage tank 5 through an induced draft fan 3. The reactor jacket 14 plays a certain role in heat preservation for the reactor 1 during normal production. When the reactor is shut down in an emergency, the emergency pump 20 quickly pumps cooling water into the reactor jacket 14 to cool the reactor 1; the liquid phase temporary storage tank 7 and the emergency pump 20 play a role in standby emergency. The active heat exchanger 6 is used for heat exchange and cooling. The reactor 1 is connected to a connecting pipeline 10, and the connecting pipeline 10 is sequentially connected to a nitrogen pipeline 11, a propylene feed pipeline 12 and an ammonia feed pipeline 13, and the connection between the nitrogen pipeline 11 and the connecting pipeline 10 is located on the side close to the reactor 1. The reactor 1 is connected with an air inlet pipe 9, and the reactor 1 is provided with a safety air outlet 15. The safety air outlet 15 is connected with the induced draft fan 3, and a gas mixer 4 is provided between the induced draft fan 3 and the gas temporary storage tank 5, and a nitrogen inlet gas mixer pipe 16 is provided on the gas mixer 4. A circulation pipe 19 is provided between the spray water storage tank 8 and the spray plate 18, and the liquid phase temporary storage tank 7 is connected with the circulation pipe 19 through an emergency pump 20. The circulation pipe 19 is connected with the reactor jacket 14 through a reactor jacket inlet pipe 21, and a reactor jacket outlet pipe 22 is connected to the reactor jacket 14. A spray water tank inlet pipe 17 is connected between the liquid phase temporary storage tank 7 and the spray water storage tank 8, and the connection between the spray water tank inlet pipe 17 and the liquid phase temporary storage tank 7 is close to the top of the liquid phase temporary storage tank 7.

[0025] The above-mentioned acrylonitrile cracking reaction protection device, when in operation, comprises the following steps:

[0026] (1) Ammonia, propylene and air enter the reactor 1 through the ammonia feed pipe 13, the propylene feed pipe 12 and the air inlet pipe 9 in sequence to react. After the reaction is completed, they enter the neutralization tower 2 through the pipe, and the active heat exchanger 6, the spray water storage tank 8 and the spray plate 18 start working; (2) When an emergency occurs and the vehicle needs to be stopped, the emergency pump 20 is quickly turned on to pump cooling water into the neutralization tower 2 and the reactor jacket 14 to cool the reactor 1 and the neutralization tower 2; (3) At the same time, the induced draft fan 3 is turned on to introduce the gas phase in the reactor 1 into the gas mixer 4, mix it with nitrogen to reduce the content of dangerous gases, and then enter the gas temporary storage tank 5 for storage.

Claims

1. An acrylonitrile cracking reaction protection device, characterized in that: The invention comprises a reactor (1), wherein the reactor (1) is connected to a neutralization tower (2) via a pipeline, a reactor jacket (14) is provided on the outside of the reactor (1), a spray plate (18) is provided inside the neutralization tower (2), the neutralization tower (2) is connected to a liquid phase temporary storage tank (7) via an active heat exchanger (6), the liquid phase temporary storage tank (7) is connected to the spray plate (18) via a spray water storage tank (8), and the reactor (1) is connected to a gas temporary storage tank (5) via an induced draft fan (3); A circulation pipeline (19) is provided between the spray water storage tank (8) and the spray plate (18), and the liquid phase temporary storage tank (7) is connected to the circulation pipeline (19) via an emergency pump (20); The circulation pipeline (19) is connected to the reactor jacket (14) via an inlet reactor jacket pipeline (21), and an outlet reactor jacket pipeline (22) is connected to the reactor jacket (14).

2. The acrylonitrile cracking reaction protection device according to claim 1, characterized in that: The reactor (1) is connected to a connecting pipe (10), and the connecting pipe (10) is connected in sequence to a nitrogen pipe (11), a propylene feed pipe (12) and an ammonia feed pipe (13), and the connection point between the nitrogen pipe (11) and the connecting pipe (10) is located on a side close to the reactor (1).

3. The acrylonitrile cracking reaction protection device according to claim 1, characterized in that: The reactor (1) is connected to an air inlet pipe (9), and a safety air outlet (15) is provided on the reactor (1).

4. The acrylonitrile cracking reaction protection device according to claim 3, characterized in that: The safety gas outlet (15) is connected to the induced draft fan (3), a gas mixer (4) is provided between the induced draft fan (3) and the gas temporary storage tank (5), and a nitrogen inlet gas mixer pipeline (16) is provided on the gas mixer (4).

5. The acrylonitrile cracking reaction protection device according to claim 1, characterized in that: A spray water storage tank inlet pipe (17) is connected between the liquid phase temporary storage tank (7) and the spray water storage tank (8), and the connection between the spray water storage tank inlet pipe (17) and the liquid phase temporary storage tank (7) is close to the top of the liquid phase temporary storage tank (7).

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