A non-low-temperature catalytic purification helium recovery device and a method for producing helium
Through non-low temperature catalytic purification technology, multi-stage molecular sieve and catalytic decomposition technology, combined with air separation device and Stirling refrigeration cycle, the problems of helium scarcity and high-cost extraction are solved, and efficient and compact helium enrichment and Improved supply security.
Patent Information
- Application Number
- CN202411162314.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-23
- Publication Date
- 2024-12-24
- Estimated Expiration
- 2044-08-23
AI Technical Summary
As a rare non-renewable resource, helium has a rare content in the atmosphere and is highly concentrated. It is difficult for the prior art to extract helium from natural gas efficiently and at low cost, affecting the safety of helium supply.
Using a non-low temperature catalytic purification helium recovery device, using pressure nitrogen in the air separation device as the source of cooling capacity, and supplemented by Stirling refrigeration cycle, helium enrichment in natural gas is achieved through multi-stage molecular sieve and catalytic decomposition technology. , including 5A molecular sieve, N2 adsorption membrane, CH4, H2, CO catalytic decomposition and 10X molecular sieve.
It has achieved efficient enrichment of helium in natural gas. Compared with low-temperature distillation technology, the equipment is compact, small in area, rapid start-up, and the elasticity of the production scale is expanded while the energy consumption remains unchanged, which has improved helium production and supply. Security.
Smart Images
Figure CN118687339B_ABST
Abstract
Description
Technical Field
[0001] The invention discloses a helium recovery device for non-low-temperature catalytic purification and a method for producing helium, belonging to the field of gas separation. Background Art
[0002] In recent years, helium, as a vital rare gas in aerospace, scientific research, high-tech industrial manufacturing and other fields, has become an important strategic resource that countries around the world attach great importance to. The primary application areas of my country's helium resources include low-temperature superconductivity, balloon carrier gas, semiconductors, optical fiber manufacturing, vacuum leak detection, etc. Helium is a scarce non-renewable resource. Its content in the atmosphere is extremely rare, and the cost of enrichment is very high. The content in natural gas ranges from a few thousandths to a few percent. Therefore, the helium currently used mainly comes from natural gas. The average helium content in natural gas is thousands of times higher than that in the air. Therefore, dehelium from natural gas is an important means to increase helium production and maintain the security of my country's helium supply. Summary of the invention
[0003] The present invention develops a non-low-temperature catalytic purification helium recovery device and a method for producing helium, using PN (pressure nitrogen) in the air separation unit ASU as the main cooling source of the device of the present invention, and supplemented by the Stirling refrigeration cycle to provide supplementary cooling to liquefy natural gas. After liquefaction, the natural gas is flashed by secondary throttling and the helium-rich gas is collected; the remaining LNG is supercooled and transported to the LNG storage tank. The helium-rich gas passes through 5A molecular sieve → N2 adsorption membrane I → N2 adsorption membrane II → CH4, H2, CO catalytic decomposition → 10X molecular sieve → N2 adsorption membrane III to obtain 4.5n~5n helium.
[0004] To achieve the purpose of the present invention, the present invention provides a non-low-temperature catalytic purification helium recovery device, which consists of a catalytic system and a purification system. The catalytic system consists of a heat exchanger, a pre-compressor, a supercharger, a primary gas-liquid separation tank, a secondary gas-liquid separation tank, and a vacuum device, which are connected to each other through pipelines, wherein the heat exchanger is also provided with a cold system and a cold circulation replenishment system, the heat exchanger is connected to the purification system, and the purification system consists of a 5A molecular sieve, N2 adsorption membrane I, N2 adsorption membrane II, CH4, H2, CO catalytic decomposer, 10X molecular sieve, N2 adsorption membrane III, which are sequentially connected to each other through pipelines.
[0005] Preferably, one end of the pre-compressor is connected to the raw natural gas, and the other end is connected to the heat exchanger, the heat exchanger is connected to the booster, and the booster is pressurized and then connected to the heat exchanger, and then connected to the primary gas-liquid separation tank through the heat exchanger, wherein the upper gas outlet of the primary gas-liquid separation tank is connected to the heat exchanger, and then the heat exchanger is connected to the purification system for purification, and the lower liquid outlet is connected to the secondary gas-liquid separation tank.
[0006] Preferably, the upper gas outlet of the secondary gas-liquid separation tank is connected to the upper gas outlet of the primary gas-liquid separation tank, and the two gases flow into the heat exchanger together, and the lower liquid outlet of the secondary gas-liquid separation tank is provided with two pipelines, which are respectively connected to the heat exchanger, one of which is connected to the LNG storage tank for storage after passing through the heat exchanger, and the other is connected to the natural gas pipeline network after passing through the heat exchanger.
[0007] Preferably, the cooling system is composed of an air separation unit ASU and an expander. The air separation unit ASU is first connected to a heat exchanger, the heat exchanger is then connected to the expander, and the expander is then connected back to the air separation unit ASU to realize circulation.
[0008] Preferably, the cold circulation replenishment system is a Stirling refrigerator, and both ends of the Stirling refrigerator are respectively connected to heat exchangers to realize cold circulation replenishment.
[0009] A method for producing helium by a helium recovery device without low-temperature catalytic purification, the method comprising the following steps:
[0010] 1) Evacuate and replace the air in the pipeline;
[0011] 2) Bare cooling device, open the cooling system and cooling circulation supplement system to provide bare cooling for the system;
[0012] 3) Introducing natural gas to separate crude helium;
[0013] 4) Purify crude helium into pure helium gas.
[0014] As a preferred method: the method of vacuuming and replacing the air in the pipeline in step 1 is:
[0015] Step 1: Open the valve, start the vacuum pumping device, and pump the vacuum for 8 to 10 hours. When the vacuum degree of the system pipeline farthest from the vacuum pumping device is lower than 10Pa, turn off the vacuum pumping device.
[0016] Step 2: Use nitrogen to purge and replace the residual air in the system pipeline for 6 to 7 hours. When the outlet dew point of the replaced nitrogen drops to -100°C and there are no solid particle impurities at the outlet, stop nitrogen purging and replacement;
[0017] Step three, open the vacuum pump again to exhaust the nitrogen in the system pipeline, and stop vacuum pumping when the vacuum degree of the system pipeline farthest from the vacuum pumping device is lower than 10Pa. After vacuum pumping and replacement are completed, close all valves of the device.
[0018] As a preferred embodiment, the specific method of starting the refrigeration system and the refrigeration circulation supplement system in step 2 is:
[0019] After the vacuuming of the pipeline in step 1 is completed, a bare cooling device is required, and the Stirling refrigerator is turned on. The system cold source supplement is started, and a refrigeration loop is formed with the Stirling refrigerator through a heat exchanger. After the Stirling refrigerator runs stably for 2 to 3 hours, the air separation unit ASU is slowly opened, and the pressure nitrogen in the air separation unit ASU returns to the air separation unit ASU through a heat exchanger and an expander. In the system startup stage, the pressure nitrogen provides a cold source for the bare cooling of the device of the present invention together with the Stirling refrigerator through the heat exchanger, and the expander does not have an expansion effect.
[0020] As a preferred embodiment: the bare cooling time in step 2 is 16 to 18 hours. After the system temperature measuring point drops to the specified value, the valve is slowly opened, and the room temperature natural gas is compressed by the pre-compressor and enters the heat exchanger, and then enters the booster from the heat exchanger; the boosted natural gas enters the heat exchanger again, and the boosted natural gas after cooling enters the primary gas-liquid separation tank through the heat exchanger, wherein the top of the primary gas-liquid separation tank is a gas flow channel, and the bottom is a liquid flow channel, and the liquid flow channel flows into the secondary gas-liquid separation tank, and the upper gas flow channel of the secondary gas-liquid separation tank merges with the gas flow channel at the top of the first gas-liquid separation tank and then flows into the heat exchanger and then directly passes through the purification system for purification, while part of the liquid below the secondary gas-liquid separation tank passes through the heat exchanger to the LNG storage tank, and the other part passes through the heat exchanger and then flows into the natural gas pipeline network.
[0021] As a preference: the specific purification method of the purification system in step 4 is:
[0022] The crude helium coming out of the heat exchanger enters the purification system, first passes through a 5A molecular sieve to remove H2O and most of CO; then enters N2 adsorption membrane I to remove most of N2. The gas at the outlet of N2 adsorption membrane I contains 65% helium (V / V). The gas at the outlet of N2 adsorption membrane I enters N2 adsorption membrane II to adsorb a small amount of N2. The gas at the outlet of N2 adsorption membrane II contains 87% helium V / V. After removing most of N2, the gas at the outlet of N2 adsorption membrane II enters CH4, H2, and CO for catalytic decomposition. The catalyst for the catalytic decomposition of CH4, H2, and CO is Pd&CuO. The working temperature range is 270℃~320℃. N2 adsorption membrane II The outlet gas contains CH4, H2, CO, and a trace amount of N2. After entering the catalytic decomposition of CH4, H2, and CO, under the catalytic action of oxygen addition, CH4, H2, and CO react with oxygen to generate H2O and CO2. The impurities at the outlet of the catalytic decomposition of CH4, H2, and CO are H2O, CO2, and O2. The outlet gas of the catalytic decomposition of CH4, H2, and CO enters the 10X molecular sieve to remove H2O and CO2. The helium content of the outlet gas of the 10X molecular sieve is 99.9% V / V. The outlet gas of the 10X molecular sieve enters the N2 adsorption membrane III to adsorb trace amounts of N2. The outlet gas of the N2 adsorption membrane III is 4.5n~5n He.
[0023] The present invention discloses a non-low-temperature catalytic purification helium recovery device and a method for producing helium, which utilizes PN (pressure nitrogen) in an air separation unit ASU as the main cooling source of the device, and is supplemented by a Stirling refrigeration cycle to provide supplementary cooling and liquefied natural gas. After liquefaction, the natural gas undergoes secondary throttling flash evaporation and collects helium-rich gas; the remaining LNG is supercooled and transported to an LNG storage tank. Specifically: ① PN (pressure nitrogen) from ASU (air separation unit) expands after heat exchange and rewarming, and the expansion work is used to cool the natural gas for secondary compression; ② High-pressure natural gas is liquefied after heat exchange and then throttled and flashed to produce helium-rich gas, which is then heat exchanged and rewarmed to remove the helium purification module; ③ After throttling and cooling, part of the LNG liquid continues to be throttled as part of the system's cooling capacity, and is merged into the natural gas pipeline network after heat exchange and vaporization, and the other part is supercooled and transported to the LNG storage tank; ④ After rewarming, the helium-rich gas passes through 5A molecular sieve → N2 adsorption membrane I → N2 adsorption membrane II → CH4, H2, CO catalytic decomposition → 10X molecular sieve → N2 adsorption membrane III to obtain 4.5n~5n. The present invention makes full use of the cold source of air separation and utilizes the low-temperature gas separation method to efficiently enrich helium in natural gas. Compared with low-temperature distillation for helium enrichment, the equipment is compact and small, occupies a small area, and can be started quickly. Moreover, under the condition of unchanged energy consumption, the elasticity of production scale change (30% to 150%) is much greater than that of low-temperature distillation (60% to 120%). BRIEF DESCRIPTION OF THE DRAWINGS
[0024] Figure 1 It is a schematic diagram of the composition of the present invention;
[0025] Figure 2 It is a schematic diagram of the structure of the purification system in the present invention. DETAILED DESCRIPTION
[0026] The present invention will be described in detail with reference to the accompanying drawings: Figure 1-2As shown, the present invention is a non-low-temperature catalytic purification helium recovery device, which consists of a catalytic system and a purification system. The catalytic system consists of a heat exchanger 9, a pre-compressor 4, a supercharger 7, a primary gas-liquid separation tank 11, a secondary gas-liquid separation tank 15, and a vacuum device, which are connected to each other through pipelines, wherein the heat exchanger 9 is also provided with a cold system and a cold circulation replenishment system, the heat exchanger 9 is connected to the purification system, and the purification system consists of a 5A molecular sieve 20, an N2 adsorption membrane I 21, an N2 adsorption membrane II 22, a CH4, H2, CO catalytic decomposer 23, a 10X molecular sieve 24, and an N2 adsorption membrane III 25, which are sequentially connected to each other through pipelines, one end of the pre-compressor 4 is connected to the raw natural gas, and the other end is connected to the heat exchanger 9. The heat exchanger 9 is connected to the booster 7, and the booster 7 is connected to the heat exchanger 9 after boosting, and then connected to the primary gas-liquid separation tank 11 through the heat exchanger 9, wherein the upper gas outlet of the primary gas-liquid separation tank 11 is connected to the heat exchanger 9, and the heat exchanger 9 is connected to the purification system for purification, and the lower liquid outlet is connected to the secondary gas-liquid separation tank 15, and the upper gas outlet of the secondary gas-liquid separation tank 15 is connected to the upper gas outlet of the primary gas-liquid separation tank 11, and the two gases flow into the heat exchanger 9 together, and the lower liquid outlet of the secondary gas-liquid separation tank 15 is provided with two pipelines, and the two pipelines are respectively connected to the heat exchanger 9, one of which is connected to the LNG storage tank for storage after passing through the heat exchanger 9, and the other is connected to the natural gas pipeline network after passing through the heat exchanger 9.
[0027] The cooling system is composed of an air separation unit ASU and an expander 3. The air separation unit ASU is first connected to a heat exchanger 9, and the heat exchanger 9 is then connected to the expander 3, and the expander 3 is then connected back to the air separation unit ASU to realize circulation. The cooling circulation supplement system is a Stirling refrigerator 41, and both ends of the Stirling refrigerator 41 are respectively connected to the heat exchanger 9 to realize cooling circulation supplement.
[0028] The specific implementation method is:
[0029] The invention discloses a non-low-temperature catalytically purified helium recovery device and a method for producing helium, which are used to remove helium from natural gas and collect LNG helium-rich flash vapor; and then obtain 4.5n-5n helium through molecular sieve adsorption, catalytic cracking and nitrogen removal adsorption.
[0030] Close all valves of the device. Before starting the device of the present invention, it is necessary to evacuate and replace the air in the pipeline: Step 1, open valve L6, valve C8, valve M10, valve D12, valve F14, valve G16, valve H17, valve J18, open the vacuum device, evacuate for 8 to 10 hours, wait until the vacuum degree of the system pipeline at the farthest end of the vacuum device is lower than 10Pa, and then close the vacuum device. Step 2, use nitrogen to purge and replace the residual air in the system pipeline for 6 to 7 hours, and stop nitrogen purging and replacement when the outlet dew point of the replaced nitrogen drops to -100°C and there are no solid particle impurities at the outlet. Step 3, open the vacuum device again, discharge the nitrogen in the system pipeline, wait until the vacuum degree of the system pipeline at the farthest end of the vacuum device is lower than 10Pa, and then stop vacuuming. After vacuuming and replacement are completed, close all valves of the device.
[0031] After the pipeline is evacuated, a bare cooling device is required, and the Stirling refrigerator 41 is turned on. The system cold source supplement begins to be used, and a refrigeration circuit is formed through the cold end outlet 32 of the heat exchanger 9, the cold end inlet 39 of the heat exchanger 9 and the Stirling refrigerator 41. After the Stirling refrigerator 41 runs stably for 2 to 3 hours, slowly open the valve A2, and the PN pressure nitrogen in the air separation unit ASU1 returns to the air separation unit ASU1 through the cold end inlet 38 of the heat exchanger 9, the cold end outlet 31 of the heat exchanger 9, the valve A2, and the expander 3. It should be pointed out that during the system startup phase, the PN pressure nitrogen passes through the heat exchanger 9 and the Stirling refrigerator 41 to provide a cold source for the bare cooling of the device of the present invention, and the expander 3 does not have an expansion effect.
[0032] After 16-18 hours of bare cooling, when the system temperature point drops to the specified value, slowly open valve B5, and the normal temperature natural gas is compressed by the pre-compressor 4 and enters the hot end inlet 26 of the heat exchanger 9. After cooling, the compressed natural gas enters the booster 7 through the hot end outlet 33 of the heat exchanger 9; slowly open valve C8, and the boosted natural gas enters the hot end inlet 27 of the heat exchanger 9; open valve M10, and the boosted natural gas enters the first gas-liquid separation tank 11 through the hot end outlet 34 of the heat exchanger 9 and valve M10 after cooling. It should be pointed out here that there is no liquid accumulation in the first gas-liquid separation tank 11 and the second gas-liquid separation tank 15 during the system startup phase, and the throttling natural gas is discharged from the gas outlets at the top of the first gas-liquid separation tank 11 and the second gas-liquid separation tank 15. It should be pointed out here that during the startup phase of the device, the expander 3 does not work and there is no expansion work output, while the input work of the booster 7 comes from the expansion work output of the expander 3, so the booster 7 does not work under the premise that the expander 3 does not work.
[0033] Open valve E13, valve D12, valve F14, valve G16, valve K19, valve H17, valve J18, and throttle valve 40, and the low-temperature natural gas passes through the heat exchanger 9 and then flows into the natural gas network through the process pipeline. It should be noted that during the equipment startup phase, the system pipelines are all low-temperature natural gas, and continuous cooling is required with the help of the process pipeline.
[0034] The device of the present invention continues to cool down through the low-temperature natural gas in the pipeline until the temperature of the hot end outlet 34 of the heat exchanger 9 reaches the set value. Close valve D12, valve K19, valve H17, valve J18, and liquid begins to accumulate at the bottom of the primary gas-liquid separation tank 11.
[0035] When the liquid level at the bottom of the primary gas-liquid separation tank 11 reaches the specified level, slowly open valve D12 and valve K19, and the liquid at the bottom of the primary gas-liquid separation tank 11 enters the secondary gas-liquid separation tank 15. Open valve K19, and the gas at the top of the secondary gas-liquid separation tank 15 merges with the gas at the top of the primary gas-liquid separation tank 11 and enters the cold end inlet 35 of the heat exchanger 9.
[0036] After the bottom of the secondary gas-liquid separation tank 15 reaches the specified liquid level, the valve H17 is slowly opened, and the liquid at the bottom of the secondary gas-liquid separation tank 15 is throttled and cooled by the throttle valve 40 and then enters the cold end inlet 37 of the heat exchanger 9. After being reheated and vaporized by the heat exchanger 9, it flows out from the cold end outlet 30 of the heat exchanger 9 and merges into the natural gas pipeline network.
[0037] Open valve J18, and part of the liquid at the bottom of the secondary gas-liquid separation tank 15 enters the hot end inlet 29 of the heat exchanger 9, and after being supercooled by the heat exchanger 9, it exits from the hot end outlet 36 of the heat exchanger 9 to the LNG storage tank.
[0038] When liquid begins to accumulate at the bottom of the primary gas-liquid separation tank 11, the expander 3 starts to start and outputs expansion work to the booster 7. After the boosting, the liquefaction rate of the natural gas through the throttle valve M10 and the valve D12 is significantly improved, and the helium removal rate is also improved. The gas at the top of the primary gas-liquid separation tank 11 and the gas at the top of the secondary gas-liquid separation tank 15 are helium-rich gas. After merging, they are reheated by the heat exchanger 9 and then removed from the helium adsorption purification system. It is emphasized here that after the device of the present invention is stably operated, if the helium content of the gas at the cold end outlet 28 of the heat exchanger 9 does not meet the design requirements and does not reach 95% of the design value, it will be merged into the natural gas pipeline through the process pipeline; if it reaches 95% of the design value, it will enter the purification system.
[0039] The crude helium at the cold end outlet 28 of the heat exchanger 9 mainly contains impurities such as CH4, N2, H2, H2O, CO, etc., which need to be removed accordingly. The crude helium at the cold end outlet 28 of the heat exchanger 9 enters the purification system, first passes through the 5A molecular sieve 20 to remove H2O and most of CO; then enters the N2 adsorption membrane Ⅰ 21 to remove most of N2. The helium content of the gas at the outlet of the N2 adsorption membrane Ⅰ 21 is 65% V / V.
[0040] The outlet gas of N2 adsorption membrane Ⅰ21 enters N2 adsorption membrane Ⅱ22, adsorbs a small amount of N2, and the outlet gas of N2 adsorption membrane Ⅱ22 contains helium at 87% V / V. After removing most of N2, the outlet gas of N2 adsorption membrane Ⅱ22 enters CH4, H2, CO catalytic decomposition 23. The catalyst of CH4, H2, CO catalytic decomposition 23 is Pd&CuO, and the working temperature range is 270℃~320℃.
[0041] The outlet gas of N2 adsorption membrane II 22 contains CH4, H2, CO, and a trace amount of N2. After entering CH4, H2, CO catalytic decomposition 23, CH4, H2, CO react with oxygen to generate H2O and CO2 under the catalytic action of oxygen addition. The impurities at the outlet of CH4, H2, CO catalytic decomposition 23 are H2O, CO2, and O2.
[0042] The outlet gas of CH4, H2, and CO catalytic decomposition 23 enters 10X molecular sieve 24 to remove H2O and CO2. The outlet gas of 10X molecular sieve 24 contains 99.9% V / V helium. The outlet gas of 10X molecular sieve 24 enters N2 adsorption membrane III 25 to adsorb trace N2. The outlet gas of N2 adsorption membrane III 25 is 4.5n~5n He.
[0043] The present invention discloses a non-low-temperature catalytic purification helium recovery device and a method for producing helium, which utilizes PN (pressure nitrogen) in an air separation unit ASU as the main cooling source of the device, and is supplemented by a Stirling refrigeration cycle to provide supplementary cooling and liquefied natural gas. After liquefaction, the natural gas undergoes secondary throttling flash evaporation and collects helium-rich gas; the remaining LNG is supercooled and transported to an LNG storage tank. Specifically: ① The PN (pressure nitrogen) from the air separation unit ASU (air separation unit) is expanded after heat exchange and rewarming, and the expansion work is used to cool the natural gas for secondary compression; ② The high-pressure natural gas is liquefied after heat exchange and then throttled and flashed to produce helium-rich gas, which is then heat exchanged and rewarmed to remove the helium purification module; ③ After throttling and cooling, part of the LNG liquid continues to be throttled as part of the system's cooling capacity, and is merged into the natural gas pipeline network after heat exchange and vaporization, and the other part is supercooled and transported to the LNG storage tank; ④ After rewarming, the helium-rich gas passes through 5A molecular sieve → N2 adsorption membrane I → N2 adsorption membrane II → CH4, H2, CO catalytic decomposition → 10X molecular sieve → N2 adsorption membrane III to obtain 4.5n~5n helium. The present invention makes full use of the cold source of air separation and utilizes the low-temperature gas separation method to efficiently enrich helium in natural gas. Compared with low-temperature distillation for helium enrichment, the equipment is compact and small, occupies a small area, and can be started quickly. Moreover, under the condition of unchanged energy consumption, the elasticity of production scale change (30% to 150%) is much greater than that of low-temperature distillation (60% to 120%).
Claims
1. A non-low-temperature catalytic purification helium recovery device, which consists of a catalytic system and a purification system, characterized in that: The catalytic system is composed of a heat exchanger (9), a pre-compressor (4), a supercharger (7), a primary gas-liquid separation tank (11), a secondary gas-liquid separation tank (15), and a vacuum pump, which are connected to each other through pipelines, wherein the heat exchanger (9) is also provided with a cooling system and a cooling circulation replenishment system, and the heat exchanger (9) is connected to a purification system, which is composed of a 5A molecular sieve (20), a N2 adsorption membrane I (21), a N2 adsorption membrane II (22), a CH4, H2, CO catalytic decomposer (23), a 10X molecular sieve (24), a N2 adsorption membrane The attached membrane III (25) is connected to each other in sequence through pipelines; one end of the pre-compressor (4) is connected to the raw natural gas, and the other end is connected to the heat exchanger (9); the heat exchanger (9) is connected to the booster (7); the booster (7) is connected to the heat exchanger (9) after pressurization, and then connected to the primary gas-liquid separation tank (11) through the heat exchanger (9); after the upper gas outlet of the primary gas-liquid separation tank (11) is connected to the heat exchanger (9), the heat exchanger (9) is connected to the purification system for purification, and the lower liquid outlet is connected to the secondary gas-liquid separation tank (15).
2. The non-low temperature catalytic purification helium recovery device according to claim 1 is characterized in that: The upper gas outlet of the secondary gas-liquid separation tank (15) is connected to the upper gas outlet of the primary gas-liquid separation tank (11), and the two gases flow into the heat exchanger (9) together, and the lower liquid outlet of the secondary gas-liquid separation tank (15) is provided with two pipelines, and the two pipelines are respectively connected to the heat exchanger (9), one of which passes through the heat exchanger (9) and is connected to the LNG storage tank for storage, and the other passes through the heat exchanger (9) and is connected to the natural gas pipeline network.
3. The non-low temperature catalytic purification helium recovery device according to claim 1 is characterized in that: The refrigeration system is composed of an air separation unit ASU (1) and an expander (3). The air separation unit ASU (1) is first connected to a heat exchanger (9), the heat exchanger (9) is then connected to the expander (3), and the expander (3) is then connected back to the air separation unit ASU (1) to achieve circulation.
4. The non-low temperature catalytic purification helium recovery device according to claim 1 is characterized in that: The cold circulation replenishment system is a Stirling refrigerator (41), and both ends of the Stirling refrigerator (41) are respectively connected to the heat exchanger (9) to achieve cold circulation replenishment.
5. A method for producing helium according to the non-low-temperature catalytic purification helium recovery device according to any one of claims 1 to 4, characterized in that: The method comprises the following steps: 1) Evacuate and replace the air in the pipeline; 2) Bare cooling device, open the cooling system and cooling circulation supplement system to provide bare cooling for the system; 3) Introducing natural gas to separate crude helium; 4) Purify crude helium into pure helium gas.
6. The method for producing helium by the non-low temperature catalytic purification helium recovery device according to claim 5, characterized in that: The method of vacuuming and replacing the air in the pipeline in step 1 is: Step 1: Open the valve, start the vacuum pumping device, and pump the vacuum for 8 to 10 hours. When the vacuum degree of the system pipeline farthest from the vacuum pumping device is lower than 10Pa, turn off the vacuum pumping device. Step 2: Use nitrogen to purge and replace the residual air in the system pipeline for 6 to 7 hours. When the outlet dew point of the replaced nitrogen drops to -100°C and there are no solid particle impurities at the outlet, stop nitrogen purging and replacement; Step three, open the vacuum pump again to exhaust the nitrogen in the system pipeline, and stop vacuum pumping when the vacuum degree of the system pipeline farthest from the vacuum pumping device is lower than 10Pa. After vacuum pumping and replacement are completed, close all valves of the device.
7. The method for producing helium by the non-low temperature catalytic purification helium recovery device according to claim 5, characterized in that: The specific method of starting the cooling system and the cooling circulation supplement system in step 2 is: After the vacuum pumping of the pipeline is completed in step 1, a bare cooling device is required, and the Stirling refrigerator (41) is turned on. The system cold source supplement is started, and a refrigeration circuit is formed through the heat exchanger (9) and the Stirling refrigerator (41). After the Stirling refrigerator (41) has been running stably for 2 to 3 hours, the air separation unit ASU (1) is slowly turned on, and the pressurized nitrogen in the air separation unit ASU (1) is returned to the air separation unit ASU (1) through the heat exchanger (9) and the expander (3). In the system startup stage, the pressurized nitrogen passes through the heat exchanger (9) and the Stirling refrigerator (41) to provide a cold source for the bare cooling of the device of the present invention, and the expander (3) does not perform an expansion function.
8. The method for producing helium by the non-low temperature catalytic purification helium recovery device according to claim 5, characterized in that: In step 2, the bare cooling time is 16 to 18 hours. After the system temperature measuring point drops to a specified value, the valve is slowly opened. The normal temperature natural gas is compressed by the pre-compressor (4) and enters the heat exchanger (9), and then enters the booster (7) from the heat exchanger (9); the boosted natural gas enters the heat exchanger (9) again. After cooling, the boosted natural gas enters the primary gas-liquid separation tank (11) through the heat exchanger (9), wherein the top of the primary gas-liquid separation tank (11) is a gas flow channel, and the bottom is a liquid flow channel. The liquid flow channel flows into the secondary gas-liquid separation tank (15). The upper gas flow channel of the secondary gas-liquid separation tank (15) merges with the gas flow channel at the top of the primary gas-liquid separation tank (11), and then flows into the heat exchanger (9) and then directly passes through the purification system for purification. A part of the liquid at the bottom of the secondary gas-liquid separation tank (15) passes through the heat exchanger (9) and goes to the LNG storage tank, and the other part passes through the heat exchanger (9) and then flows into the natural gas pipeline network.
9. The method for producing helium by the helium recovery device without low temperature catalytic purification according to claim 5, characterized in that: The specific purification method of the purification system in step 4 is: The crude helium gas from the heat exchanger (9) enters the purification system, first passes through a 5A molecular sieve (20) to remove H2O and most of CO; then enters the N2 adsorption membrane I (21) to remove most of N2. The helium content of the gas at the outlet of the N2 adsorption membrane I (21) is 65% (V / V). The gas at the outlet of the N2 adsorption membrane I (21) enters the N2 adsorption membrane II (22) to adsorb a small amount of N2. The helium content of the gas at the outlet of the N2 adsorption membrane II (22) is 87% V / V. After most of the N2 is removed, the gas at the outlet of the N2 adsorption membrane II (22) enters the CH4, H2, CO catalytic decomposer (23). The catalyst of the CH4, H2, CO catalytic decomposer (23) is Pd and CuO, and the working temperature range is 270°C to 320°C. The N2 adsorption membrane The outlet gas of Ⅱ (22) contains CH4, H2, CO, and a trace amount of N2. After entering the CH4, H2, CO catalytic decomposer (23), under the catalytic action of oxygen addition, CH4, H2, CO react with oxygen to generate H2O and CO2. The impurities at the outlet of the CH4, H2, CO catalytic decomposer (23) are H2O, CO2 and O2. The outlet gas of the CH4, H2, CO catalytic decomposer (23) enters the 10X molecular sieve (24) to remove H2O and CO2. The outlet gas of the 10X molecular sieve (24) contains helium at 99.9% V / V. The outlet gas of the 10X molecular sieve (24) enters the N2 adsorption membrane Ⅲ (25) to adsorb trace amounts of N2. The outlet gas of the N2 adsorption membrane Ⅲ (25) is 4.5n~5n He.