Device for detecting leakage of nitrogen system of cyclohexanecarboxylic acid production line
By designing a device for detecting nitrogen system leakage on the cyclohexaforic acid production line, and using water sealing tanks and hydrogen sensors/smoke sense alarms to detect hydrogen leakage, the safety hazards of hydrogen entering the nitrogen system are solved, and safety and cost-effectiveness are improved.
Patent Information
- Application Number
- CN202422341490.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-25
- Publication Date
- 2025-08-12
- Estimated Expiration
- 2034-09-25
AI Technical Summary
In the prior art, during the production process of cyclohexanoic acid, the hydrogen in the hydrogenation reactor is prone to leak into the nitrogen system, resulting in safety hazards. Nitrogen replacement is required every time the machine is shut down for maintenance, which increases costs and risks.
Design a device to detect the leakage of nitrogen system in the cyclohexanoic acid production line, including a hydrogenation reactor, a hydrogen supply system, a nitrogen supply system, a buffer tank, a nitrogen valve, a bypass pipe, a water seal tank and a hydrogen sensor/smoke alarm. The hydrogen leakage is detected and alarmed in a timely manner through the water seal tank to prevent hydrogen from entering the nitrogen system.
Effectively avoid hydrogen entering the nitrogen system, reduce safety hazards, reduce hydrogen usage, reduce production costs, and improve production safety.
Smart Images
Figure CN223217029U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of cyclohexanecarboxylic acid production, in particular to a device for detecting leakage of a nitrogen system of a cyclohexanecarboxylic acid production line. Background Art
[0002] Cyclohexanecarboxylic acid can be used to synthesize anti-pregnancy drugs and the new schistosomiasis treatment drug praziquantel. It can also be used as a compatibilizer for vulcanized rubber, a petroleum clarifier, a pesticide, a dye, and other organic compounds. Cyclohexanecarboxylic acid is prepared by a variety of methods, with the Grignard reagent method, benzoic acid catalytic hydrogenation, cyclohexene carbon monoxide addition, and methods using cyclohexanone as a raw material being preferred. The catalytic hydrogenation of benzoic acid to cyclohexanecarboxylic acid plays a significant role in organic synthesis.
[0003] During the production of cyclohexanecarboxylic acid by catalytic hydrogenation of benzoic acid, the reaction temperature of the hydrogenation reactor is 140-170°C, and the reaction pressure is around 1.4 MPa. High temperature, high pressure, and frequent valve opening and closing will cause certain damage to the valves. The hydrogenation reactor is connected to a nitrogen buffer tank and a hydrogen buffer tank. Normally, the nitrogen buffer tank has a low pressure, below 0.6 MPa, and the reactor is often under high pressure. Each hydrogenation reactor reaction requires hydrogen and nitrogen replacement. If the valve leaks, the hydrogen in the hydrogenation reactor will flow into the nitrogen buffer tank along the nitrogen pipeline. The nitrogen buffer tank is also connected to a large number of equipment such as the melting kettle, the front material receiving tank, and the emptying buffer tank. Nitrogen replacement is required for each shutdown and maintenance. If hydrogen is filled into the nitrogen buffer tank, there is a major safety hazard.
[0004] Therefore, if a device can be developed to detect leakage in the nitrogen system of the cyclohexanecarboxylic acid production line, it can timely detect the leakage of hydrogen in the hydrogenation reactor into the nitrogen pipeline and prevent hydrogen from entering the nitrogen system. This will definitely improve production safety and greatly promote the development of cyclohexanecarboxylic acid production by catalytic hydrogenation of benzoic acid. Utility Model Content
[0005] In view of the shortcomings of the existing technology, the purpose of the present invention is to provide a device for detecting leakage of the nitrogen system of a cyclohexanecarboxylic acid production line, which can timely detect the leakage of hydrogen in the hydrogenation reactor into the nitrogen pipeline, prevent hydrogen from entering the nitrogen system, and improve production safety.
[0006] In order to solve the above technical problems, the present invention provides a device for detecting leakage of the nitrogen system of a cyclohexanecarboxylic acid production line, comprising a hydrogenation reactor, a hydrogen supply system connected to the hydrogenation reactor, and a nitrogen supply system connected to the hydrogenation reactor. The nitrogen supply system comprises a buffer tank connected to the hydrogenation reactor via a pipeline, a first nitrogen valve and a second nitrogen valve provided on the pipeline connecting the buffer tank and the hydrogenation reactor, a bypass pipe connected to the pipeline between the first nitrogen valve and the second nitrogen valve, a vent valve provided on the bypass pipe, and a water seal tank connected to the bottom of the bypass pipe.
[0007] As a further improved technical solution, the device for detecting leakage of the nitrogen system of the cyclohexanecarboxylic acid production line provided by the utility model further comprises a hydrogen sensor arranged above the water seal tank.
[0008] As a further improved technical solution, the device for detecting leakage of the nitrogen system of the cyclohexanecarboxylic acid production line provided by the utility model further includes a smoke alarm arranged above the water seal tank.
[0009] In the absence of conflict, the aforementioned improved technical solutions can be implemented individually or in combination.
[0010] The technical solution provided by the utility model can effectively prevent the hydrogen in the hydrogenation reactor from entering the nitrogen system, eliminating potential safety hazards. BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of this application. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention but do not constitute an improper limitation of the present invention. In the accompanying drawings:
[0012] Figure 1 This is a structural diagram of a device for detecting leakage of a nitrogen system in a cyclohexanecarboxylic acid production line according to an embodiment. Implementation Method
[0013] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.
[0014] like Figure 1 The device shown for detecting leaks in the nitrogen system of a cyclohexanecarboxylic acid production line includes a hydrogenation reactor 1, a hydrogen supply system 2 connected to the hydrogenation reactor 1, and a nitrogen supply system 3 connected to the hydrogenation reactor 1. The nitrogen supply system 3 includes a buffer tank 4 connected to the hydrogenation reactor 1 via a pipeline, a first nitrogen valve 5 and a second nitrogen valve 6 provided on the pipeline connecting the buffer tank 4 and the hydrogenation reactor 1, a bypass pipe 7 connected by a pipeline between the first nitrogen valve 5 and the second nitrogen valve 6, a vent valve 8 provided on the bypass pipe 7, and a water seal tank 9 connected to the bottom of the bypass pipe 7.
[0015] The reaction pressure of the hydrogenation reactor 1 is about 1.4Mpa, and the pressure in the nitrogen buffer tank is relatively low, generally not exceeding 0.6Mpa. During the hydrogenation reaction of the hydrogenation reactor 1, the first nitrogen valve 5 is in a closed state to prevent the material in the hydrogenation reactor 1 from leaking out; the second nitrogen valve 6 is also closed to prevent the nitrogen in the nitrogen buffer tank 4 from being discharged outward; the vent valve 8 is opened. If the first nitrogen valve 5 or the second nitrogen valve 6 leaks, the leaked material enters the water seal tank 9, and bubbles are generated in the water seal tank 9, which can be discovered in time. During the operation, after the hydrogenation reactor 1 is discharged, nitrogen needs to be used to replace the gas in the reactor. When nitrogen needs to be used to replace the gas in the hydrogenation reactor 1, the valve on the pipeline of the hydrogen supply system 2 entering the hydrogenation reactor 1 is closed, the vent valve 8 is closed, the first nitrogen valve 5 and the second nitrogen valve 6 are opened, and nitrogen enters the hydrogenation reactor 1 to replace the gas in the reactor. During normal production, the water level in the water seal tank 9 submerges the bottom end of the bypass pipe 7. The vent valve 8 is closed during nitrogen replacement. After the combustible gas is replaced twice with nitrogen and is qualified, the first nitrogen valve 5 and the second nitrogen valve 6 are closed, and the vent valve 8 is opened. By observing whether there is bubbling in the water seal tank 9, it is determined whether there is internal leakage in the valve. When a large number of bubbles are found in the water seal tank 9, it is detected that the first nitrogen valve 5 or the second nitrogen valve 6 is leaking. By detecting whether the leaked gas is hydrogen or nitrogen or other identification methods, it can be further detected to determine whether it is the first nitrogen valve 5 or the second nitrogen valve 6 that is leaking. The leaking valve needs to be replaced in time.
[0016] The technical solution provided by the present invention can effectively prevent the hydrogen in the hydrogenation reactor 1 from entering the nitrogen system, eliminating potential safety hazards. Since hydrogen leakage in the hydrogenation reactor 1 can be detected in time, it is beneficial to reduce hydrogen consumption and production costs.
[0017] As one example, Figure 1 As shown, based on the aforementioned basic solution, the device for detecting nitrogen system leaks in a cyclohexanecarboxylic acid production line provided by the present invention further includes a hydrogen sensor 10 disposed above the water seal tank 9. When a hydrogen leak occurs, the hydrogen content in the environment will increase. When the hydrogen sensor 10 detects that the hydrogen content in the environment exceeds the standard, it issues an alarm and other related information, further improving the safety of the system.
[0018] As one example, Figure 1 As shown, based on the aforementioned basic solution, the device for detecting nitrogen system leaks in a cyclohexanecarboxylic acid production line provided by the present invention further includes a smoke alarm 11 disposed above the water seal tank 9. When the hydrogen content in the environment exceeds the standard and a fire occurs, the smoke alarm 11 promptly issues an alarm message.
[0019] The above description is merely a preferred embodiment of the present invention and does not limit the present invention in any way. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.
Claims
1. A device for detecting leakage of a nitrogen system in a cyclohexanecarboxylic acid production line, comprising a hydrogenation reactor (1), a hydrogen supply system (2) connected to the hydrogenation reactor (1), and a nitrogen supply system (3) connected to the hydrogenation reactor (1), characterized in that: The nitrogen supply system (3) comprises a buffer tank (4) connected to the hydrogenation reactor (1) through a pipeline, a first nitrogen valve (5) and a second nitrogen valve (6) provided on the pipeline connecting the buffer tank (4) and the hydrogenation reactor (1), a bypass pipe (7) connected to the pipeline between the first nitrogen valve (5) and the second nitrogen valve (6), a vent valve (8) provided on the bypass pipe, and a water seal tank (9) connected to the bottom of the bypass pipe (7).
2. The device for detecting leakage of nitrogen system of cyclohexanecarboxylic acid production line according to claim 1, wherein It also has a hydrogen sensor (10) arranged above the water seal groove (9).
3. The device for detecting leakage of nitrogen system of cyclohexanecarboxylic acid production line according to claim 1, wherein It also has a smoke alarm (11) arranged above the water seal groove (9).