Helium extraction device with pressure equalization filling function and extraction method

Abstract

This invention discloses a helium extraction device and method with pressure equalization and filling functions. The device includes a filling and storage unit, with the raw gas for which comes from a helium extraction device. The filling and storage unit includes a filling device, a fixed tube bundle, a filling compressor, an external tube bundle, and a pressure equalization pipeline and a compression input pipeline connected in parallel. The upstream of the pressure equalization pipeline and the compression input pipeline is connected to the filling device via a first connecting pipeline, and the downstream of the pipeline is connected to the external tube bundle via a fourth connecting pipeline. The compression input pipeline is sequentially equipped with the fixed tube bundle and the filling compressor. Valves are installed on the pressure equalization pipeline and the compression input pipeline. In this invention, the fixed tube bundle provides storage space for upstream helium, reducing input time. The pressure equalization of the external tube bundle by the fixed tube bundle and the filling device shortens the filling time and reduces the time the external tube bundle or its vehicle spends at the plant, thus improving safety.

Description

Technical Field

[0001] This invention relates to the field of chemical gas separation technology, and more specifically to a helium extraction device and extraction method with pressure equalization filling function. Background Technology

[0002] Helium is a colorless and odorless gas under normal conditions. It is the only substance that cannot be solidified under standard atmospheric pressure, and its unique physical properties determine its special uses. Helium is also a precious rare gas with wide applications in industry and research. Currently, helium resources mainly rely on extraction from natural gas, which contains 1 vol% to 8 vol% helium. Due to its low content, extraction is difficult and costly.

[0003] Helium is extremely rare in the atmosphere, making extraction difficult and costly. Currently, it is mainly extracted from natural gas feedstock gas (BOG). However, because the helium content in LNG feedstock gas is very low, only about 300-500 ppm, and the helium content in BOG is about 0.5%-1%, the return on investment is also low.

[0004] The existing method for filling high-purity helium gas is to directly fill the high-purity helium extracted from BOG into the high-pressure tube bundle through a compressor. This method takes a long time, generally about 15 to 20 days, causing the high-pressure gas tube bundle to remain in the chemical plant for a long time, which increases the safety risks. Summary of the Invention

[0005] The technical problem to be solved by this invention is how to shorten the filling time of the external tube bundle.

[0006] The present invention solves the above-mentioned technical problems through the following technical means: a helium extraction device with pressure equalization and filling function, including a filling and storage unit, wherein the raw material gas of the filling and storage unit comes from a helium extraction device, the filling and storage unit includes a filling device, a fixed tube bundle, a filling compressor, an external tube bundle, and a pressure equalization pipeline and a compression input pipeline connected in parallel, the pressure equalization pipeline and the compression input pipeline are connected to the filling device upstream through a first connecting pipeline, and connected to the external tube bundle downstream through a fourth connecting pipeline, the fixed tube bundle and the filling compressor are sequentially arranged on the compression input pipeline, and valves are arranged on the pressure equalization pipeline and the compression input pipeline.

[0007] As a preferred technical solution, the pressure equalization pipeline includes a fifth connecting pipeline. The upstream of the fifth connecting pipeline is connected to the filling device through the first connecting pipeline, and the downstream is connected to the external tube bundle through the fourth connecting pipeline. The fifth connecting pipeline is equipped with a pressure equalization pneumatic valve and a pressure relief pneumatic valve.

[0008] As a preferred technical solution, the compression input pipeline includes a second connecting pipeline and a third connecting pipeline. The downstream of the first connecting pipeline is connected to the fixed tube bundle through the second connecting pipeline. The fixed tube bundle is connected to the vehicle-mounted compressor through the third connecting pipeline. The vehicle-mounted compressor is connected to the external tube bundle through the fourth connecting pipeline.

[0009] As a preferred technical solution, the second connecting pipe is provided with a fixed tube bundle air inlet manual valve, the third connecting pipe is provided with a pressure relief pneumatic valve, a pressure relief and pressure reducing valve, and a loading compressor air inlet manual valve in sequence, and the fourth connecting pipe is provided with a filling arm air inlet manual valve and a filling arm in sequence.

[0010] As a preferred technical solution, a sixth connecting pipeline is also included, which is connected to the equalizing pipeline, and the sixth connecting pipeline is equipped with an air extraction valve and an air extraction pump.

[0011] As a preferred technical solution, the helium extraction device includes a catalytic dehydrogenation unit, a crude helium purification unit, and a helium refining unit connected in sequence, with the helium refining unit located upstream of the filling and storage unit.

[0012] As a preferred technical solution, the catalytic dehydrogenation unit includes a circulating compressor and a catalytic dehydrogenation device. The catalytic dehydrogenation device includes a dehydrogenation section and a dehydration section. The upstream feed gas is connected to the inlet of the circulating compressor. The outlet of the circulating compressor is connected to the inlet of the dehydrogenation section of the catalytic dehydrogenation device. The outlet of the dehydrogenation section is connected to the inlet of the dehydration section of the catalytic dehydrogenation device and the inlet of the circulating compressor. The outlet of the dehydration section of the catalytic dehydrogenation device is connected to the crude helium purification unit.

[0013] As a preferred technical solution, the crude helium purification unit includes a membrane separation device, a booster compressor, and a PSA device. The outlet of the dehydration section of the catalytic dehydrogenation device in the catalytic dehydrogenation unit is connected to the inlet of the membrane separation device in the crude helium purification unit. The permeate outlet of the membrane separation device is connected to the inlet of the booster compressor, and the non-permeate outlet of the membrane separation device is returned to the original BOG pipeline network. The outlet of the booster compressor is connected to the inlet of the PSA device. The product gas outlet of the PSA device is connected to the downstream helium refining unit, and the desorption gas outlet of the PSA device is connected to the inlet of the circulating compressor in the catalytic dehydrogenation unit.

[0014] As a preferred technical solution, the helium refining unit includes a helium refining device. The product gas outlet of the PSA device in the crude helium purification unit is connected to the inlet of the helium refining device in the helium refining unit, and the outlet of the helium refining device is connected to the filling and storage unit.

[0015] The present invention also provides an extraction method using the above-mentioned helium extraction device with pressure equalization and filling function. The fixed tube bundle is filled by the filling device. After the external tube bundle is connected to the fourth connecting pipe, the pressure of the external tube bundle is equalized by the filling device and the fixed tube bundle. After the pressure equalization is completed, the remaining helium in the fixed tube bundle is injected into the external tube bundle by the loading compressor.

[0016] The beneficial effects of this invention are as follows:

[0017] (1) In this invention, by setting up a fixed tube bundle, storage space can be provided for upstream helium, reducing input time. By equalizing the pressure of the external tube bundle through the fixed tube bundle and filling device, the filling time can be shortened, reducing the time for the external tube bundle or external tube bundle vehicle to access the fourth connecting pipeline, i.e., the time to stop at the plant, thus improving safety.

[0018] (2) In this invention, the process of combining membrane separation and pressure swing adsorption (PSA) with the room temperature route of crude helium purification unit is a four-unit process consisting of catalytic dehydrogenation unit, crude helium purification unit, helium refining unit, and filling and storage unit. The process route is short, energy consumption is low, equipment is relatively simple and occupies a small area, and it is fully automatic, easy to operate and stable. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the helium extraction device provided in an embodiment of the present invention;

[0020] Figure 2 This is a flowchart provided for an embodiment of the present invention;

[0021] Reference numerals: 101, Catalytic dehydrogenation unit; 1011, Circulating compressor; 1012, Catalytic dehydrogenation device; 102, Crude helium purification unit; 1021, Membrane separation device; 1022, Booster compressor; 1023, PSA device; 103, Helium refining unit; 1031, Helium refining device; 104, Filling and storage unit; 1041, Filling compressor; 401, Filling device; 402, Fixed tube bundle; 403, Loading compressor; 404, Filling arm; 405, External tube bundle; 406. Vacuum pump; 411. Filling pneumatic valve; 412. Pressure equalizing pneumatic valve; 413. Pressure relief pneumatic valve; 414. Air extraction pneumatic valve; 421. Fixed tube bundle inlet manual valve; 422. Loading compressor inlet manual valve; 423. Filling arm inlet manual valve; 431. Pressure equalizing check valve; 441. Pressure relief and pressure reducing valve; 501. First connecting pipeline; 502. Second connecting pipeline; 503. Third connecting pipeline; 504. Fourth connecting pipeline; 505. Fifth connecting pipeline; 506. Sixth connecting pipeline. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] See Figure 1 A helium extraction device with pressure equalization filling function includes a catalytic dehydrogenation unit 101, a crude helium purification unit 102, a helium refining unit 103, and a filling and storage unit 104 connected in sequence. In this embodiment, the inlet can also be an input end and the outlet can also be an output end.

[0024] The catalytic dehydrogenation unit 101 includes a circulating compressor 1011 and a catalytic dehydrogenation device 1012. The catalytic dehydrogenation device 1012 includes a dehydrogenation section and a dehydration section. The feed gas is fed into the inlet of the circulating compressor 1011. The outlet of the circulating compressor 1011 is connected to the inlet of the dehydrogenation section of the catalytic dehydrogenation device 1012. The outlet of the dehydrogenation section is connected to the inlet of the dehydration section of the catalytic dehydrogenation device 1012 and the inlet of the circulating compressor. The outlet of the dehydration section of the catalytic dehydrogenation device 1012 is connected to the crude helium purification unit 102.

[0025] The crude helium purification unit 102 includes a membrane separation device 1021, a booster compressor 1022, and a PSA device 1023, i.e., a pressure swing adsorption device. The outlet of the dehydration section of the catalytic dehydrogenation device 1012 in the catalytic dehydrogenation unit 101 is connected to the inlet of the membrane separation device 1021 in the crude helium purification unit 102. The permeate outlet of the membrane separation device 1021 is connected to the inlet of the booster compressor 1022. The non-permeate outlet of the membrane separation device 1021 is returned to the original BOG pipeline network. The outlet of the booster compressor 1022 is connected to the inlet of the PSA device 1023. The product gas outlet of the PSA device 1023 is connected to the downstream helium refining unit 103. The desorbed gas outlet of the PSA device 1023 is connected to the inlet of the circulating compressor 1011 in the catalytic dehydrogenation unit 101. The desorbed gas is recycled to improve the recovery rate.

[0026] The helium refining unit 103 includes a helium refining device 1031. The product gas outlet of the PSA device 1023 in the crude helium purification unit 102 is connected to the inlet of the helium refining device 1031 in the helium refining unit 103, and the outlet of the helium refining device 1031 is connected to the filling and storage unit 104.

[0027] The filling and storage unit 104 includes a filling compressor 1041, a filling device 401, a fixed tube bundle 402, a vehicle-mounted compressor 403, and an external tube bundle 405. The outlet of the helium refining device 1031 in the helium refining unit 103 is high-purity helium. The outlet of the helium refining device 1031 is connected to the inlet of the filling compressor 1041 in the filling and storage unit 104. The outlet of the filling compressor 1041 is connected to the filling device 401. The outlet of the filling device 401 is connected to the inlet of the fixed tube bundle 402 and the inlet of the external tube bundle 405. The outlet of the fixed tube bundle 402 is connected to the inlet of the vehicle-mounted compressor 1041 and the inlet of the external tube bundle 405. The outlet of the vehicle-mounted compressor 403 is connected to the inlet of the external tube bundle 405. High-purity helium is filled and stored at a high pressure of 20 MPa.g.

[0028] Specifically: the filling device 401 is connected to the fixed tube bundle 402 via the first connecting pipe 501 and the second connecting pipe 502; the fixed tube bundle 402 is connected to the vehicle loading compressor 403 via the third connecting pipe 503; the vehicle loading compressor 403 is connected to the external tube bundle 405 via the fourth connecting pipe 504; the filling device 401 is connected to the fourth connecting pipe 504 via the first connecting pipe 501 and the fifth connecting pipe 505; a filling pneumatic valve 411 is provided on the first connecting pipe 501, located downstream of the outlet of the filling device 401; a fixed tube bundle inlet manual valve 421 is provided on the second connecting pipe 502, allowing the fixed tube bundle to inlet... The pneumatic hand valve 421 is located upstream of the fixed tube bundle 402 and downstream of the filling pneumatic valve 411. The third connecting pipe 503 is sequentially equipped with a pressure relief pneumatic valve 413, a pressure relief and pressure reducing valve 441, and a loading compressor inlet hand valve 422. The fourth connecting pipe 504 is equipped with a filling arm inlet hand valve 423 and a filling arm 404, which is located upstream of the external tube bundle 405. The fifth connecting pipe 505 is equipped with a pressure equalization pneumatic valve 412 and a pressure equalization check valve 431. The fourth connecting pipe 504 is connected to a sixth connecting pipe 506, which is equipped with a vacuuming pneumatic valve 414 and a vacuum pump 406.

[0029] Working principle:

[0030] The process combines membrane separation and pressure swing adsorption (PSA) with a crude helium purification unit 102. The production process includes: a catalytic dehydrogenation unit 101, a crude helium purification unit 102, a helium refining unit 103, and a filling and storage unit 104.

[0031] The raw material gas flow rate is about 30 m3 / h, the helium content is about 40%-50%, the hydrogen content is 3%-5%, with a maximum of 12%, and the remaining components are nitrogen, methane, and neon. The impurity components in the helium are separated in each unit step by step, and the final helium produced has a purity of 99.999%.

[0032] The feed gas comes from the enrichment tower process section of the natural gas liquefaction plant, is pressurized to 1.5 MPa.g by the circulating compressor 1011 in the catalytic dehydrogenation unit 101, and then sent to the catalytic dehydrogenation unit 1012;

[0033] Working principle of catalytic dehydrogenation unit 101:

[0034] The catalytic dehydrogenation unit 101 includes a catalytic dehydrogenation device 1012, a circulating compressor 1012, and a dehydration dryer connected in sequence. The dehydrogenation reactor of the catalytic dehydrogenation device is filled with a high-efficiency catalyst, which can remove hydrogen from the feed gas to below 1 ppm. The gas coming out of the catalytic reactor of the catalytic dehydrogenation device contains a large amount of reaction water. It is first cooled by a cooler, then separated by gas and liquid, and then enters a switching dehydration dryer. The dehydration dryer is filled with molecular sieve adsorbent, which can remove water from the feed gas to below 3 ppm.

[0035] The operating pressure of the circulating compressor 1011 in the catalytic dehydrogenation unit 101 is 1.5 MPa.g. The inlet buffer tank in the circulating compressor 1011 is used to receive BOG feed gas and dehydrogenation section return gas from the catalytic dehydrogenation unit 1012 to establish the balance state of the internal circulation system of the compressor. At the same time, it receives the desorbed gas from the PSA unit 1023 and the second-stage permeate gas from the membrane separation unit 1021. The outlet of the circulating compressor 1011 is pressurized to 1.6 MPa.g and enters the catalytic dehydrogenation unit 101 in the catalytic dehydrogenation unit 101.

[0036] Working principle of crude helium purification unit 102:

[0037] The crude helium purification unit 102 adopts membrane separation + pressure swing adsorption technology;

[0038] Membrane separation utilizes the partial pressure difference of gases on both sides of the membrane as the driving force to achieve separation through dissolution-diffusion-desorption. Polyimide membranes are mainly imported. In this embodiment, PRISM membranes from Air Products, Inc. are used. Membrane separation technology and pressure swing adsorption technology are used to purify helium to more than 99% and remove methane to below 500 ppm. The product gas from the membrane separation unit 1021 is pressurized to 1.6 MPa.g by the booster compressor 1022 and enters the PSA unit 1023. The product gas from the PSA unit 1023 is then sent under pressure to the downstream helium purification unit 103.

[0039] The design of the pressure swing adsorption (PSA) unit in the crude helium purification unit 102 takes into account the demethane removal characteristics of the adsorbent. Methane has a high boiling point of -161.5℃. Before the PSA product gas enters the helium refining unit 1031, it passes through the heat exchanger in the helium refining unit 103, which lowers the temperature. Methane may freeze and become blocked. To reduce the methane content to a certain level, freeze-blocking is avoided, and the stability of the unit operation is increased. A fault-tolerant mechanism is added.

[0040] Working principle of helium refining unit 103:

[0041] The helium purification unit 103 is a low-temperature helium purifier with a working pressure of 1.4 MPa.g. After heat exchange and adsorption, high-purity helium of over 99.999% is obtained and sent to the filling and storage unit 104 for filling. The system is equipped with two purifiers, one for use and one for backup. When one is working, the other is activated. The continuous working capacity of a single unit is greater than 20 hours. The condensation and adsorption process is carried out at a liquid nitrogen temperature of 77K, i.e. -196℃. The remaining impurity components are adsorbed by utilizing the adsorption characteristics of activated carbon and molecular sieves in a low-temperature environment, so that the helium purity is increased to 99.999%. After being pressurized to 20 MPa.g by the filling compressor, it enters the filling device and is distributed to the tube bundle high-pressure storage.

[0042] Working principle of the filling storage unit 104:

[0043] The helium refining unit 103 has an outlet pressure of 1.4 MPa.g. High-purity helium is first pressurized to 20 MPa.g by the filling compressor 1041, then enters the fixed tube bundle 402 through the filling device 401. The process stops after the fixed tube bundle 402 is full. In this embodiment, the capacity of the fixed tube bundle 402 is 4500. When the external control unit 405 or external control unit vehicle has a vehicle capacity of 4000 -4500 After the external tube bundle 405 is connected to the fourth connecting pipe 504, the fixed tube bundle 402 or the fixed tube bundle 40 and the filling device 401 first jointly fill the external tube bundle 405 with equalized gas. After equalization, the fixed tube bundle 402 has 10MPa.g-11MPa.g of high-purity helium gas remaining. Then, the remaining gas in the fixed tube bundle 402 is depressurized to 1.2MPa.g through the pressure relief pneumatic valve 413 and the pressure relief and pressure reducing valve 441 and then enters the loading compressor 403 to be pressurized to 20MPa.g. The filling stops when the external tube bundle vehicle pressure reaches 20MPa.g from 10MPa.g.

[0044] Working principle:

[0045] In this embodiment, the difference from the prior art lies in the addition of a fixed tube bundle 402. The fixed tube bundle 402 is filled by the filling device 401. After the external tube bundle 405 is connected to the fourth connecting pipeline, the external tube bundle 405 is pressure-equalized by the filling device 401 and the fixed tube bundle 402. This pressure equalization greatly shortens the filling time and reduces the time for the external tube bundle 405 or the external tube bundle vehicle to connect to the fourth connecting pipeline 504, i.e., the time spent at the plant. This is because in the prior art, the filling device 401 directly... The external tube bundle 405 is connected for filling. Due to the limitations of gas transportation and high-purity helium pressure, it takes 10-15 days to fill the external tube bundle 405 completely. This process requires the external tube bundle 405 to be continuously parked, which is highly dangerous. However, with the fixed tube bundle 402, it is only necessary to fill the fixed tube bundle 402 with the filling device 401. This process does not require connecting the external tube bundle 405, which shortens the time for the external tube bundle 405 or the external tube bundle vehicle to be connected to the fourth connecting pipeline, and greatly reduces the time the external tube bundle vehicle is parked at the plant.

[0046] This equalization process can inject about half the capacity of the external tube bundle 405 with helium. After equalization, the remaining helium in the fixed tube bundle 402 is injected into the external tube bundle 405 through the loading compressor 403. During this process, the filling device 401 can continuously input helium into the external tube bundle 405 through the fifth connecting pipe, thereby further reducing the filling time and ensuring that the loading time can be completed within 3-15 hours.

[0047] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A helium extraction device with pressure equalization filling function, characterized in that, The system includes a filling and storage unit, whose feed gas comes from a helium extraction unit. The filling and storage unit includes a filling device, a fixed tube bundle, a filling compressor, an external tube bundle, and parallel-connected equalization and compression input lines. The equalization and compression input lines are connected upstream to the filling device via a first connecting line and downstream to the external tube bundle via a fourth connecting line. The compression input line is sequentially equipped with the fixed tube bundle and the filling compressor. Valves are installed on the equalization and compression input lines. The compression input line includes a second connecting line and a third connecting line. Downstream of the first connecting line, it is connected to the fixed tube bundle via the second connecting line. The fixed tube bundle is connected to the loading compressor via the third connecting line. The loading compressor is connected to the external tube bundle via the fourth connecting line. The catalytic dehydrogenation unit includes a recirculating compressor and a catalytic dehydrogenation device. The chemical dehydrogenation unit includes a dehydrogenation section and a dehydration section. The upstream feed gas is fed into the inlet of the circulating compressor. The outlet of the circulating compressor is connected to the inlet of the dehydrogenation section of the catalytic dehydrogenation unit. The outlet of the dehydrogenation section is connected to the inlet of the dehydration section of the catalytic dehydrogenation unit and the inlet of the circulating compressor. The outlet of the dehydration section of the catalytic dehydrogenation unit is connected to the crude helium purification unit. The crude helium purification unit includes a membrane separation unit, a booster compressor, and a PSA unit. The outlet of the dehydration section of the catalytic dehydrogenation unit is connected to the inlet of the membrane separation unit in the crude helium purification unit. The permeate outlet of the membrane separation unit is connected to the inlet of the booster compressor. The non-permeate outlet of the membrane separation unit returns to the original BOG pipeline network. The outlet of the booster compressor is connected to the inlet of the PSA unit. The product gas outlet of the PSA unit is connected to the downstream helium refining unit. The desorbed gas outlet of the PSA unit is connected to the inlet of the circulating compressor in the catalytic dehydrogenation unit.

2. The helium extraction device with pressure equalization filling function according to claim 1, characterized in that, The equalizing pipeline includes a fifth connecting pipeline. The upstream of the fifth connecting pipeline is connected to the filling device through the first connecting pipeline, and the downstream is connected to the external tube bundle through the fourth connecting pipeline. The fifth connecting pipeline is equipped with an equalizing pneumatic valve and a pressure relief pneumatic valve.

3. The helium extraction device with pressure equalization filling function according to claim 1, characterized in that, The second connecting pipe is equipped with a fixed tube bundle air inlet manual valve, the third connecting pipe is equipped with a pressure relief pneumatic valve, a pressure relief and pressure reducing valve, and a loading compressor air inlet manual valve in sequence, and the fourth connecting pipe is equipped with a filling arm air inlet manual valve and a filling arm in sequence.

4. A helium extraction device with pressure equalization filling function according to claim 1, characterized in that, It also includes a sixth connecting pipeline, which is connected to the equalizing pipeline. The sixth connecting pipeline is equipped with an air extraction valve and an air extraction pump.

5. A helium extraction device with pressure equalization filling function according to claim 1, characterized in that, The helium extraction unit includes a catalytic dehydrogenation unit, a crude helium purification unit, and a helium refining unit connected in sequence. The helium refining unit is located upstream of the filling and storage unit.

6. A helium extraction device with pressure equalization filling function according to claim 1, characterized in that, The helium refining unit includes a helium refining device. The product gas outlet of the PSA device in the crude helium purification unit is connected to the inlet of the helium refining device in the helium refining unit, and the outlet of the helium refining device is connected to the filling and storage unit.

7. An extraction method using a helium extraction apparatus with pressure equalization and filling function as described in any one of claims 1-6, characterized in that, The fixed tube bundle is filled by the filling device. After the external tube bundle is connected to the fourth connecting pipe, the external tube bundle is pressure equalized by the filling device and the fixed tube bundle. After the pressure equalization is completed, the remaining helium in the fixed tube bundle is injected into the external tube bundle by the loading compressor.

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