Nitrogen generating system with micro-oxygen analyzer protection function

Abstract

The utility model discloses a kind of nitrogen generation systems with micro-oxygen analyzer protection function, including purification device, pure nitrogen storage tank, micro-oxygen analyzer, third pipeline and fourth pipeline are connected in parallel at the gas outlet of the purification device, fourth control valve is provided on the fourth pipeline, the other side of fourth control valve is empty, third control valve is provided on the third pipeline, fifth pipeline, sixth pipeline, seventh pipeline, tenth pipeline are connected in parallel in the rear of third control valve, seventh control valve is provided on the seventh pipeline, the other side of seventh control valve is empty via throttle valve, the inlet of the fifth pipeline with pure nitrogen storage tank is communicated, fifth control valve is provided on the fifth pipeline, micro-oxygen analyzer is installed at the end of the tenth pipeline, the sixth pipeline is communicated with pure nitrogen storage tank, sixth control valve is provided on the sixth pipeline.This nitrogen generation system is configured with micro-oxygen analyzer protection device, and the service life of micro-oxygen analyzer is obviously prolonged.

Description

Technical Field

[0001] This utility model specifically relates to a nitrogen generation system with a micro-oxygen analyzer protection function, belonging to the technical field of nitrogen generation equipment. Background Technology

[0002] Nitrogen is a commonly used reaction gas and protective gas in industry. For example, in the production of vanadium-nitrogen alloys, nitrogen needs to be continuously introduced into the furnace so that vanadium-containing materials react with nitrogen to form vanadium nitride. The food and pharmaceutical industries require nitrogen covering for preservation and to prevent oxidation and spoilage. Nitrogen can be produced using pressure swing adsorption (PSA) generators. PSA equipment uses carbon molecular sieves as adsorbents and utilizes the principle of pressure swing adsorption to produce nitrogen. Current technology typically uses a combination of a PSA generator and a purification unit to obtain qualified high-purity nitrogen for use in the vanadium-nitrogen alloy industry. The main generator produces ordinary nitrogen with a purity of approximately 99.5%, which is then purified to remove residual oxygen, ultimately yielding nitrogen with a purity of 99.999%. In this system, an online micro-oxygen analyzer is a crucial but expensive device for monitoring nitrogen purity. The micro-oxygen analyzer uses a fuel cell sensor, which generates an electric current upon contact with oxygen to detect oxygen content. This process is irreversible and has a limited lifespan; the lifespan of the micro-oxygen analyzer ends when the fuel cell material is depleted. The oxygen content in normally purified high-purity nitrogen is around 1-10 ppm, and a micro-oxygen analyzer can be used continuously for about 5 years. However, in situations such as power outages, valve malfunctions in the general nitrogen generator, or air compressor failures, the oxygen content in the general nitrogen will rise sharply. Alternatively, if the purification unit's purification capacity is insufficient, or if the ammonia decomposition unit malfunctions, or if the liquid ammonia tank is empty, the general nitrogen cannot be purified, resulting in excessive oxygen content. These factors will cause the fuel cell sensor to deplete rapidly and fail, leading to monitoring failure and shutdown of the nitrogen generation system. Replacement of the micro-oxygen analyzer is necessary, increasing costs. Therefore, existing nitrogen generation systems generally lack effective protection measures for the micro-oxygen analyzer. Summary of the Invention

[0003] To address the problems existing in the prior art, this utility model provides a nitrogen generation system with a micro-oxygen analyzer protection device, aiming to effectively protect the micro-oxygen analyzer and extend its service life during the nitrogen generation process.

[0004] The technical solution of this utility model is as follows:

[0005] A nitrogen generation system with micro-oxygen analyzer protection function includes a purification device, a pure nitrogen storage tank, and a micro-oxygen analyzer. A third and fourth pipe are connected in parallel at the outlet of the purification device. A fourth control valve is installed on the fourth pipe, with the other side of the fourth control valve venting. A third control valve is installed on the third pipe. A fifth, sixth, seventh, and tenth pipe are connected in parallel downstream of the third control valve. A seventh control valve is installed on the seventh pipe, with the other side of the seventh control valve venting via a throttling valve. The fifth pipe is connected to the inlet of the pure nitrogen storage tank and has a fifth control valve. A micro-oxygen analyzer is installed at the end of the tenth pipe. The sixth pipe is connected to the pure nitrogen storage tank and has a sixth control valve.

[0006] An eleventh pipe is also connected to the outlet of the pure nitrogen storage tank.

[0007] Furthermore, the nitrogen generation system also includes a general nitrogen supply pipeline. A first pipeline, a second pipeline, and an eighth pipeline are connected in parallel after the general nitrogen supply pipeline. A second control valve is installed on the second pipeline, and the other side of the second control valve is vented. A general nitrogen analyzer is connected to the end of the eighth pipeline. The first pipeline is connected to the air inlet of the purification device, and a first control valve is installed on the first pipeline.

[0008] Furthermore, the nitrogen generation system also includes a control system, wherein the first control valve, the second control valve, the third control valve, the fourth control valve, the fifth control valve, the sixth control valve, the seventh control valve, the general nitrogen analyzer, the purification device, and the micro-oxygen analyzer are all electrically connected to the control system.

[0009] Furthermore, the other end of the nitrogen supply pipeline is connected to a pressure swing adsorption nitrogen generator.

[0010] Beneficial Effects: This invention, by installing multiple pipelines between the purification unit and the pure nitrogen storage tank, and equipping these pipelines with various control valves (including a third, fourth, fifth, sixth, and seventh control valves) and a micro-oxygen analyzer, ensures that if the oxygen content in the nitrogen output from the purification unit exceeds the standard for any reason, the micro-oxygen analyzer will send an alarm signal to the control system. The control system will then promptly shut off the relevant control valves and purge the pipeline connected to the micro-oxygen analyzer with high-purity nitrogen from the pure nitrogen storage tank, preventing excessive burning of the micro-oxygen analyzer sensor and shortening its lifespan. Once the fault is cleared and the purification unit outputs qualified high-purity nitrogen, the system can resume operation. Therefore, this nitrogen generation system is equipped with a micro-oxygen analyzer protection device, significantly extending the service life of the micro-oxygen analyzer. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the layout structure of the nitrogen generation system described in this utility model.

[0012] The meanings of the symbols in the diagram are as follows:

[0013] 0. General nitrogen gas supply pipeline, 1. First control valve, 2. Second control valve, 3. Third control valve, 4. Fourth control valve, 5. Fifth control valve, 6. Sixth control valve, 7. Seventh control valve, 8. General nitrogen analyzer, 9. Purification device, 10. Micro-oxygen analyzer, 11. Pure nitrogen storage tank.

[0014] 11 First pipe, 21 Second pipe, 31 Third pipe, 41 Fourth pipe, 51 Fifth pipe, 61 Sixth pipe, 71 Seventh pipe, 81 Eighth pipe, 101 Tenth pipe, 111 Eleventh pipe. Detailed Implementation

[0015] The present invention will now be described in detail with reference to the accompanying drawings. In this invention, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated.

[0016] like Figure 1 As shown, a nitrogen generation system with micro-oxygen analyzer protection function includes a pressure swing adsorption (PSA) nitrogen generator, a general nitrogen analyzer 8, a purification device 9, a micro-oxygen analyzer 10, a pure nitrogen storage tank 11, and a control system. These devices are connected by pipelines, and multiple control valves are installed on the pipelines. The control system (including a PLC) controls the operation of the equipment and the opening or closing of the control valves. The PSA nitrogen generator and the control system are not shown in the figure. The PSA nitrogen generator is used to prepare general nitrogen with a purity of approximately 99.5%, while the purification device further increases the purity of the general nitrogen to over 99.99%. Both the PSA nitrogen generator and the purification device are existing technologies, and their structure and function will not be described in detail in this patent.

[0017] The nitrogen output from the pressure swing adsorption (PSA) nitrogen generator is supplied to this nitrogen generation system through nitrogen supply pipeline 0. A first pipeline 11, a second pipeline 21, and an eighth pipeline 81 are connected in parallel after the nitrogen supply pipeline 0. A second control valve 2 is installed on the second pipeline 21, with the other side of the second control valve 2 venting. A nitrogen analyzer 8 is connected to the end of the eighth pipeline 81. The first pipeline 11 is connected to the left air inlet of the purification device 9, and a first control valve 1 is installed on the first pipeline 11. The nitrogen analyzer 8 monitors the nitrogen output from the PSA nitrogen generator. If the detection data is normal, the second control valve 2 closes and the first control valve 1 opens, supplying nitrogen to the purification device 9. When the nitrogen purity is lower than the set value, the purification device's capacity is insufficient to purify to the required value, and the oxygen content will increase. At this time, the nitrogen analyzer outputs an alarm signal to the control system PLC. The PLC closes the first control valve 1 and simultaneously opens the second control valve 2, venting the substandard nitrogen and awaiting maintenance and troubleshooting by personnel until the nitrogen purity is within acceptable limits. Once the fault is cleared and the gas supply is normal, the valve returns to its initial gas supply state. The combined configuration of the first control valve 1, the second control valve 2, and the nitrogen analyzer 8 prevents substandard nitrogen with high oxygen content from being supplied to the purification unit, ensuring the normal operation of the purification unit.

[0018] After further purification by the purification device 9, the purity of the ordinary nitrogen is greatly improved, and high-purity nitrogen gas is obtained and supplied to the pure nitrogen storage tank 11. A third pipe 31 and a fourth pipe 41 are connected in parallel at the right outlet of the purification device 9. A fourth control valve 4 is installed on the fourth pipe 41, and the other side of the fourth control valve 4 is vented. A third control valve 3 is installed on the third pipe 31. A fifth pipe 51, a sixth pipe 61, a seventh pipe 71, and a tenth pipe 101 are connected in parallel behind (on the right side) of the third control valve 3. A seventh control valve 7 is installed on the seventh pipe 71, and the other side of the seventh control valve 7 is vented via a throttle valve. The fifth pipe 51 is connected to the left inlet of the pure nitrogen storage tank 11. A fifth control valve 5 is installed on the fifth pipe 51. A micro-oxygen analyzer 10 is installed at the end of the tenth pipe 101. The sixth pipe 61 is connected to the pure nitrogen storage tank 11. A sixth control valve 6 is installed on the sixth pipe 61. The micro-oxygen analyzer 10 is located on the left side of the sixth pipe 61 near the end of the tenth pipe 101. The sixth pipe 61 mainly serves as a reverse purging function. During normal operation, the fourth control valve 4, the sixth control valve 6, and the seventh control valve 7 are closed, while the third control valve 3 and the fifth control valve 5 are open. The purification device 9 supplies gas to the pure nitrogen storage tank 11, and the micro-oxygen analyzer 10 monitors the purity of the supplied gas to ensure it is within the acceptable range.

[0019] When the purification unit 9 malfunctions (e.g., abnormal ammonia decomposition, empty liquid ammonia tank), the oxygen content in its output gas will significantly increase, triggering an alarm on the micro-oxygen analyzer 10. Specifically, when the micro-oxygen analyzer 10 detects excessive oxygen content in the supplied gas, it sends an alarm signal to the control system. The control system simultaneously closes the third control valve 3 and the fifth control valve 5, and opens the fourth control valve 4 to vent the incoming gas. Simultaneously, it opens the sixth control valve 6 and the seventh control valve 7, using high-purity nitrogen stored in the pure nitrogen storage tank 11 to purge and vent the pipeline connected to the micro-oxygen analyzer 10. This reverse purging can continue for a certain period before ending. After reverse purging, the oxygen content in the tenth pipeline 101 is reduced, preventing the micro-oxygen analyzer 10 from operating in a high-oxygen environment for extended periods, which could lead to excessive wear and tear and shorten its service life. After purging, the sixth control valve 6 and the seventh control valve 7 can be closed. Then, the staff waits for the purification unit 9 to malfunction. Once the malfunction is resolved, the staff sends a reset signal to the control system via a button. At this time, the fourth control valve 4 is closed, and the third control valve 3 and the fifth control valve 5 are opened to resume gas supply to the pure nitrogen storage tank 11. Simultaneously, the micro-oxygen analyzer 10 continuously monitors whether the gas supply quality is up to standard. If it is still not up to standard, the aforementioned purging process is repeated; if it is up to standard, normal operation resumes. An eleventh pipe 111 is also connected to the gas outlet above the pure nitrogen storage tank 11. This pipe is responsible for outputting qualified high-purity nitrogen to the next process for production use.

Claims

1. A nitrogen generation system with micro-oxygen analyzer protection function, characterized in that, The system includes a purification device, a pure nitrogen storage tank, and a micro-oxygen analyzer. A third and fourth pipeline are connected in parallel at the outlet of the purification device. A fourth control valve is installed on the fourth pipeline, with the other side of the fourth control valve venting. A third control valve is installed on the third pipeline. A fifth, sixth, seventh, and tenth pipeline are connected in parallel downstream of the third control valve. A seventh control valve is installed on the seventh pipeline, with the other side of the seventh control valve venting via a throttle valve. The fifth pipeline is connected to the inlet of the pure nitrogen storage tank and has a fifth control valve. A micro-oxygen analyzer is installed at the end of the tenth pipeline. The sixth pipeline is connected to the pure nitrogen storage tank and has a sixth control valve.

2. A nitrogen generation system with micro-oxygen analyzer protection function according to claim 1, characterized in that, An eleventh pipe is also connected to the outlet of the pure nitrogen storage tank.

3. A nitrogen generation system with micro-oxygen analyzer protection function according to claim 1, characterized in that, The nitrogen generation system also includes a general nitrogen supply pipeline. A first pipeline, a second pipeline, and an eighth pipeline are connected in parallel after the general nitrogen supply pipeline. A second control valve is installed on the second pipeline, and the other side of the second control valve is vented. A general nitrogen analyzer is connected to the end of the eighth pipeline. The first pipeline is connected to the air inlet of the purification device. A first control valve is installed on the first pipeline.

4. A nitrogen generation system with micro-oxygen analyzer protection function according to claim 3, characterized in that, The nitrogen generation system also includes a control system, wherein the first control valve, the second control valve, the third control valve, the fourth control valve, the fifth control valve, the sixth control valve, the seventh control valve, the general nitrogen analyzer, the purification device, and the micro-oxygen analyzer are all electrically connected to the control system.

5. A nitrogen generation system with micro-oxygen analyzer protection function according to claim 3, characterized in that, The other end of the nitrogen supply pipeline is connected to the pressure swing adsorption nitrogen generator.

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