Integrated device and method for extracting helium by adopting membrane separation technology

Abstract

The invention discloses an integrated device and method for extracting helium by adopting a membrane separation technology. The device comprises a multi-stage membrane treatment unit, a decarburization unit, a dehydration unit, a dehydrogenation unit, a purification unit and a helium storage unit, all the units are sequentially connected through pipelines according to the arrangement sequence; the membrane treatment unit comprises a membrane separation unit and a membrane pressurization unit; the membrane separation unit is used for concentrating helium in natural gas; the membrane pressurizing unit is used for pressurizing the permeation gas passing through the membrane separation unit; the decarburization unit is used for removing carbon dioxide in the natural gas; the purification unit comprises a pressure swing adsorption unit and a low-temperature refining unit; the pressure swing adsorption unit is used for removing impurity gas in the crude helium; the low-temperature refining unit is used for adsorbing residual impurity components after passing through the pressure swing adsorption unit. The method can reduce energy consumption and investment to a great extent, and can be matched with a cryogenic method to co-produce liquefied natural gas.

Description

Technical Field

[0001] The present invention relates to the technical field of natural gas helium extraction, and particularly relates to an integrated device and method for extracting helium by using membrane separation technology. Background Art

[0002] Helium is an extremely light, colorless, odorless monatomic gas at room temperature. Helium has a wide range of uses in the fields of medicine, optical fibers, and superconductivity, and is one of the essential gases in the high-tech field. Since helium mainly exists in natural gas, natural gas containing helium in industry is the only source for producing helium. At present, the main method for extracting helium from natural gas is the cryogenic process, that is, under cryogenic conditions, helium is separated and extracted by using its extremely low liquefaction temperature. However, the cryogenic helium extraction process has disadvantages such as high energy consumption and high investment, which is not conducive to energy conservation and consumption reduction. Summary of the Invention

[0003] In view of the above problems, the purpose of the present invention is to provide an integrated device and method for extracting helium by using membrane separation technology.

[0004] In a first aspect, an embodiment of the present invention provides an integrated device for extracting helium by using membrane separation technology, including:

[0005] A multi-stage membrane treatment unit, a decarbonization unit, a dehydration unit, a dehydrogenation unit, a purification unit, and a helium storage unit; the multi-stage membrane treatment unit, the decarbonization unit, the dehydration unit, the dehydrogenation unit, the purification unit, and the helium storage unit are sequentially connected through pipelines;

[0006] The membrane treatment unit includes a membrane separation unit and a membrane boosting unit; the membrane separation unit is used for concentrating helium in natural gas; the membrane boosting unit is used for boosting the permeate gas passing through the membrane separation unit;

[0007] The decarbonization unit is used for removing carbon dioxide from natural gas;

[0008] The purification unit includes a pressure swing adsorption unit and a cryogenic refining unit; the pressure swing adsorption unit is used for removing impurity gases in crude helium; the cryogenic refining unit is used for adsorbing the remaining impurity components after passing through the pressure swing adsorption unit 。

[0009] In one embodiment, the multi-stage membrane treatment unit includes: a primary membrane treatment unit and a secondary membrane treatment unit; the primary membrane separation unit, the primary membrane boosting unit, the decarbonization unit, the dehydration unit, the secondary membrane separation unit, the secondary membrane boosting unit, the dehydrogenation unit, the pressure swing adsorption unit, the cryogenic refining unit, and the helium storage unit are sequentially connected through pipelines;

[0010] The input port of the primary membrane separation unit is used for connecting with the external raw material natural gas pipeline network.

[0011] In one embodiment, the primary membrane separation unit is also connected to the external raw natural gas pipeline network for transporting the non-permeate gas separated by the primary membrane separation unit back to the raw natural gas pipeline network.

[0012] In one embodiment, the input port of the decarbonization unit is also connected to the raw natural gas pipeline network through a pipeline for directly receiving raw natural gas from the raw natural gas pipeline network.

[0013] In one embodiment, the secondary membrane separation unit is also connected to the input port of the primary membrane separation unit through a pipeline for transporting the non-permeate gas separated by the secondary membrane separation unit to the primary membrane separation unit.

[0014] In one embodiment, the secondary membrane separation unit is also connected to the input port of the primary membrane booster unit through a pipeline for transporting a part of the permeate gas separated by the secondary membrane separation unit back to the primary membrane booster unit.

[0015] In one embodiment, the pressure swing adsorption unit is also connected to the input port of the primary membrane booster unit through a pipeline for transporting the desorbed gas after pressure swing adsorption back to the primary membrane booster unit.

[0016] In one embodiment, the device further comprises: a natural gas liquefaction unit, a liquefied natural gas storage unit and a demethanation unit;

[0017] The natural gas liquefaction unit and the demethanation unit are sequentially connected between the dehydration unit and the dehydrogenation unit through pipelines;

[0018] The natural gas liquefaction unit has two output ports, one output port is connected to the liquefied natural gas storage unit, and the other output port is connected to the demethanation unit.

[0019] In a second aspect, an embodiment of the present invention provides a method for extracting helium from raw natural gas using the integrated device for extracting helium by membrane separation technology as described above.

[0020] In one embodiment, the primary membrane booster unit boosts the permeate gas passing through the primary separation membrane to 2000 kPa.a to 7000 kPa.a;

[0021] The secondary membrane booster unit boosts the permeate gas passing through the secondary separation membrane to 1000 kPa.a to 3000 kPa.a.

[0022] In one embodiment, the dehydrogenation unit reduces the hydrogen content to ≤1 ppm.

[0023] In one embodiment, the pressure swing adsorption unit increases the helium purity to 99.9% and above;

[0024] The low-temperature refining unit raises the purity of helium to 99.999% or higher.

[0025] The beneficial effects of the above technical solutions provided by the embodiments of the present invention at least include:

[0026] The integrated device and method for extracting helium by using the membrane separation technology provided by the embodiments of the present invention utilize the different separation and permeation effects of helium and other component gases in natural gas in the membrane, and adopt a multi-stage membrane separation technology to concentrate helium. Since the membrane separation technology can be carried out at room temperature, the energy consumption and investment are greatly reduced. In addition, through the processes of decarbonization, dehydration, dehydrogenation, pressure swing adsorption and low-temperature refining (adsorption), high-purity helium that meets the requirements can be extracted.

[0027] Further, the raw natural gas directly enters the first-stage membrane separation unit after pretreatment from the raw natural gas pipeline network, that is, the energy consumption is minimized at the source.

[0028] Further, after the natural gas passes through the first-stage membrane treatment unit and undergoes decarbonization and dehydration treatment, according to the project's reliance conditions and actual benefits, it can also be combined with the cryogenic co-production of liquefied natural gas, so that the integrated device has higher operation flexibility and realizes the effective utilization of resources.

[0029] Other features and advantages of the present invention will be described in the following specification, and part of them will become obvious from the specification or be understood by implementing the present invention. The objectives and other advantages of the present invention can be achieved and obtained through the structures specifically pointed out in the written specification, claims, and drawings.

[0030] Next, through the drawings and embodiments, the technical solutions of the present invention will be further described in detail. Description of the Drawings

[0031] The drawings are used to provide a further understanding of the present invention, and constitute a part of the specification. They are used together with the embodiments of the present invention to explain the present invention, and do not constitute a limitation to the present invention. In the drawings:

[0032] Figure 1 It is a schematic structural diagram of the integrated device for extracting helium by using the membrane separation technology in the embodiments of the present invention.

[0033] Description of the reference numerals in the drawings:

[0034] 1 - First-stage membrane separation unit; 2 - First-stage membrane booster unit; 3 - Decarbonization unit; 4 - Dehydration unit; 5 - Second-stage membrane separation unit; 6 - Second-stage membrane booster unit; 7 - Dehydrogenation unit; 8 - Pressure swing adsorption unit; 9 - Low-temperature refining unit; 10 - Helium storage unit;

[0035] 11 - Natural gas liquefaction unit 12 - Liquefied natural gas storage unit 13 - Demethanation unit. Detailed implementation mode

[0036] This embodiment provides an integrated device and method for extracting helium using membrane separation technology. Although the exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present disclosure can be more thoroughly understood and the scope of the present disclosure can be completely conveyed to those skilled in the art.

[0037] The embodiment of the present invention provides an integrated device for extracting helium using membrane separation technology, including:

[0038] A multi-stage membrane treatment unit, a decarbonization unit, a dehydration unit, a dehydrogenation unit, a purification unit, and a helium storage unit; the multi-stage membrane treatment unit, the decarbonization unit, the dehydration unit, the dehydrogenation unit, the purification unit, and the helium storage unit are sequentially connected through pipelines;

[0039] The membrane treatment unit includes a membrane separation unit and a membrane booster unit; the membrane separation unit is used for concentrating helium in natural gas; the membrane booster unit is used for boosting the pressure of the permeate gas passing through the membrane separation unit;

[0040] The decarbonization unit is used for removing carbon dioxide from natural gas;

[0041] The purification unit includes a pressure swing adsorption unit and a cryogenic refining unit; the pressure swing adsorption unit is used for removing impurity gases from crude helium; the cryogenic refining unit is used for adsorbing the remaining impurity components after passing through the pressure swing adsorption unit.

[0042] The embodiment of the present invention utilizes the difference in the degree of permeation of helium and other component gases in natural gas through the membrane, adopts multi-stage membrane separation technology to concentrate helium in natural gas, and then further purifies helium through other processes to obtain helium that meets different production and living requirements. For the convenience of description, the natural gas in the raw natural gas pipeline network in the specification is called raw natural gas, and the natural gas entering the device to be processed is called process natural gas. All the following embodiments can be referred to Figure 1 as shown.

[0043] In one embodiment, the integrated device may include, for example, a two-stage membrane treatment unit, that is, including: a primary membrane separation unit 1, a primary membrane booster unit 2, a secondary membrane separation unit 5, and a secondary membrane booster unit 6; however, the embodiment of the present invention is not limited to the above structure form of the two-stage membrane treatment unit, and more stages of membrane treatment units are still within the protection scope.

[0044] The structural connection mode of the integrated device for helium extraction using membrane separation technology is as follows: the primary membrane separation unit 1, the primary membrane pressurization unit 2, the decarbonization unit 3, the dehydration unit 4, the secondary membrane separation unit 5, the secondary membrane pressurization unit 6, the dehydrogenation unit 7, the pressure swing adsorption unit 8, the cryogenic purification unit 9, and the helium storage unit 10 are sequentially connected through pipelines.

[0045] The input port of the primary membrane separation unit 1 is connected to the external raw material natural gas pipeline network, which is used to directly receive and process the raw material natural gas. That is, the natural gas undergoes membrane separation at normal temperature as soon as it comes out of the raw material natural gas pipeline network, rather than using the energy-consuming deep cooling helium extraction process, greatly reducing energy consumption and investment.

[0046] The functions of the primary membrane separation unit 1 and the secondary membrane separation unit 5 are both to concentrate the helium in the natural gas and can remove most of the methane in the raw material natural gas. Since the pressure of the permeate gas passing through the membrane separation unit drops sharply, in order to enable the process natural gas to have a certain gas pressure during subsequent transportation, the inventor has set up membrane pressurization units after each stage of the membrane separation unit, namely the primary membrane pressurization unit 2 and the secondary membrane pressurization unit 6.

[0047] The decarbonization unit 3 is used to remove carbon dioxide in the process natural gas to a certain concentration or below, and the dehydration unit 4 is mainly used to remove the increased water content in the process natural gas during the decarbonization process to a certain concentration or below.

[0048] Similarly, the dehydrogenation unit 7 is used to remove hydrogen in the process natural gas to a certain concentration or below.

[0049] The pressure swing adsorption unit 8 and the cryogenic purification unit 9 are both process units set up to refine and purify trace impurity gases such as nitrogen, neon, and argon in the process natural gas. The pressure swing adsorption unit 8 and the cryogenic purification unit 9 can meet different helium purity requirements, and the cryogenic purification unit further purifies the helium in the process natural gas after passing through the pressure swing adsorption unit 8. These two units can be set up individually or jointly according to process requirements, and are not limited in the embodiments of the present invention.

[0050] In one embodiment, the primary permeate gas after passing through the primary membrane separation unit 1 enters the primary membrane pressurization unit 2, while the primary non-permeate gas is transported back to the raw material natural gas pipeline network through the pipeline connecting the primary membrane separation unit 1 to the external original natural gas pipeline network, thus avoiding waste of the process natural gas.

[0051] In one embodiment, in addition to being connected to the output port of the first-stage membrane pressurization unit 2, the input port of the decarbonization unit 3 is also connected to the raw natural gas pipeline network, for directly receiving raw natural gas from the raw natural gas pipeline network. For example, the transportation of the raw natural gas in this pipeline can be controlled by a valve, that is, when enriching and extracting helium, the raw natural gas can enter the subsequent unit without passing through the first-stage membrane treatment unit.

[0052] In one embodiment, in addition to being connected to the dehydration unit 4 and the second-stage membrane pressurization unit 6, the second-stage membrane separation unit 5 is also connected to the input port of the first-stage membrane separation unit 1 through a pipeline, for transporting the second-stage non-permeate gas separated by the second-stage membrane separation unit 5 to the first-stage membrane separation unit 1, so that the second-stage non-permeate gas re-enters the first-stage membrane treatment unit for re-treatment, which can maximize the helium concentration and recovery of the second-stage non-permeate gas separated from the second-stage membrane separation unit 5.

[0053] In one embodiment, the second-stage membrane separation unit 5 is also connected to the input port of the first-stage membrane pressurization unit 2 through a pipeline, for transporting a part of the second-stage permeate gas separated by the second-stage membrane separation unit 5 back to the first-stage membrane pressurization unit 2, and the other part of the second-stage permeate gas is transported to the next unit - the second-stage membrane pressurization unit 6. In this embodiment, this part of the second-stage permeate gas is continuously pressurized, decarbonized, dehydrated and second-stage membrane separated to form a cycle, to maximize the helium extraction effect.

[0054] Of course, valves and helium concentration detectors can also be set on this pipeline in this embodiment to detect the concentration of all the second-stage permeate gas passing through the second-stage membrane separation unit 5. If the detection standard is not reached, the valve is opened, and if the standard is reached, the valve is closed.

[0055] In one embodiment, in addition to being connected to the dehydrogenation unit 7 and the cryogenic refining unit 9, the pressure swing adsorption unit 8 is also connected to the input port of the first-stage membrane pressurization unit 2 through a pipeline, for transporting the desorbed gas after pressure swing adsorption back to the first-stage membrane pressurization unit 2 to form a cycle, so as to further purify helium from the desorbed gas.

[0056] In one embodiment, the integrated device further includes: a natural gas liquefaction unit 11, a liquefied natural gas storage unit 12 and a demethanation unit 13; the natural gas liquefaction unit 11 and the demethanation unit 13 are sequentially connected between the dehydration unit 4 and the dehydrogenation unit 7 through pipelines; the natural gas liquefaction unit 11 has two output ports, one output port is connected to the liquefied natural gas storage unit 12, and the other output port is connected to the demethanation unit 13.

[0057] In this embodiment, this part of the device unit mainly cooperates with the third embodiment in the embodiments of the present invention: that is, the pipeline for directly transporting raw natural gas to the decarbonization unit 3. Its main purpose is to produce liquefied natural gas. That is to say, control valves can be set on the connecting pipeline between the dehydration unit 4 and the natural gas liquefaction unit 11 to decide whether to extract liquefied natural gas according to actual production requirements. After the process natural gas passes through the natural gas liquefaction unit 11, most of the natural gas is liquefied into LNG and enters the storage unit 12 for storage. In addition, the unliquefied gas phase enters the demethanation unit 13, and the helium gas is further concentrated through the demethanation cryogenic process. Since the purity of the helium gas obtained by the demethanation cryogenic process for helium extraction is generally higher than that obtained by the membrane separation technology, this part of the process natural gas (mainly containing helium gas and other impurity gases) can directly enter the subsequent units of the integrated device for further concentration and purification of the helium gas without undergoing membrane separation again.

[0058] In a second aspect, an embodiment of the present invention provides a method for separating, enriching and extracting high-purity helium gas from helium gas in raw natural gas by using an integrated device for helium extraction by membrane separation technology.

[0059] In one embodiment, the primary membrane booster unit 2 boosts the permeate gas passing through the primary separation membrane to 2000 kPa.a to 7000 kPa.a; the secondary membrane booster unit 4 boosts the permeate gas passing through the secondary separation membrane to 1000 kPa.a to 3000 kPa.a.

[0060] In one embodiment, the dehydrogenation unit 7 reduces the hydrogen content in the process natural gas to ≤1 ppm.

[0061] In one embodiment, the pressure swing adsorption unit 8 raises the purity of helium gas to 99.9% and above; the cryogenic refining unit 9 raises the purity of helium gas to 99.999% and above.

[0062] To better illustrate the connection modes and functional effects of each unit in the integrated device of the embodiment of the present invention, the process of extracting high-purity helium gas from natural gas will be exemplified below with reference to Figure 1 , and the process of extracting high-purity helium gas from natural gas will be exemplified.

[0063] Process 1: The pre-treated raw natural gas in the raw natural gas pipeline (2000 kPa.a - 7000 kPa.a, 50 - 60 °C), whose components mainly include methane, ethane, butane, various hydrocarbons, carbon dioxide, nitrogen, hydrogen, oxygen, argon, neon, and helium, etc. Generally, the proportion of methane can reach over 80%. It is input through a pipeline into the first-stage membrane separation unit 1 for separation. The helium in the first-stage permeate gas after passing through the first-stage membrane separation unit 1 can be concentrated 8 - 10 times, and its pressure is reduced to 50 kPa.a - 60 kPa.a. While the pressure value of the first-stage non-permeate gas that does not pass through the first-stage membrane separation unit 1 is reduced by 100 kPa.a - 200 kPa.a. This part of the first-stage non-permeate gas is transported back into the raw natural gas pipeline through the pipeline between the first-stage membrane separation unit 1 and the raw natural gas pipeline. The first-stage membrane separation unit 1 can remove most of the methane in the raw natural gas.

[0064] The first-stage permeate gas after passing through the first-stage membrane separation unit 1 enters the first-stage membrane booster unit 2 for boosting. The compressor uses 3 - 5 stages of boosting, and a reciprocating compressor is preferably used to increase the pressure of this part of the first-stage permeate gas to 2000 kPa.a - 7000 kPa.a. The boosted first-stage permeate gas enters the decarbonization unit 3;

[0065] In addition, the raw natural gas can bypass the first-stage membrane treatment unit and be directly transported into the decarbonization unit 3 through the pipeline connecting the raw natural gas pipeline and the decarbonization unit 3. For example, valves can be set on each pipeline to control different transportation paths of the raw natural gas.

[0066] Process 2: The process natural gas entering the decarbonization unit 3 undergoes decarbonization treatment. For example, two processes of (MethylDiethanlamine, MDEA) amine solution decarbonization or pressure swing adsorption (PSA) decarbonization can be used. The purpose is to remove carbon dioxide in the process natural gas. After the treatment of this unit, the carbon dioxide can be removed to 50 ppm and below.

[0067] Process 3: Since the decarbonization process inevitably adds moisture to the process natural gas, the process natural gas after decarbonization needs to enter the dehydration unit 4 for dehydration. For example, the molecular sieve dehydration process can be used to dehydrate the water content to 1 ppm and below.

[0068] Process Four: The treated natural gas after decarbonization and dehydration splits into two paths. One path enters the secondary membrane separation unit 5 for another helium enrichment process at normal temperature. The secondary permeate gas passing through the secondary membrane separation unit 5 (with the pressure reduced to 50 kPa.a - 60 kPa.a), a part of it is transported back to the primary membrane booster unit 2 through the pipeline connecting the secondary membrane separation unit 5 and the input port of the primary membrane booster unit 2, thus realizing the helium enrichment cycle of the treated natural gas. Valves and helium concentration detectors can also be installed on the pipeline for this part of the secondary permeate gas to detect the concentration of all the secondary permeate gas passing through the secondary membrane separation unit 5. If the detection standard is not met, the valve is opened; if the standard is met, the valve is closed.

[0069] The other part enters the subsequent secondary membrane booster unit 6 for pressure boosting. The compressor of the secondary membrane separation unit 5 is preferably a diaphragm compressor, which increases the pressure of the permeate gas to 1000 kPa.a - 3000 kPa. The pressure-boosted secondary permeate gas then enters the dehydrogenation unit 7.

[0070] In addition, the secondary non-permeate gas passing through the secondary membrane separation unit 5 is transported back to the primary membrane separation unit 1 through the pipeline connecting the secondary membrane separation unit 5 and the input port of the primary membrane separation unit 1, forming a circulation loop.

[0071] Process Five: The treated natural gas after decarbonization and dehydration can also enter the natural gas liquefaction unit 11 through the other path to produce liquefied natural gas using cryogenic technology (temperature of -160°C). Most of the natural gas is liquefied into LNG and enters the liquefied natural gas storage unit 12. The unliquefied gas phase enters the demethanation unit 13 to concentrate helium using cryogenic technology (-196°C), and then the treated natural gas after methane removal is transported to the dehydrogenation unit 7. In the embodiment of the present invention, valves can be installed between the dehydration unit 4 and the secondary membrane separation unit 5 and / or the natural gas liquefaction unit 11 to control and adjust the transportation path of the treated natural gas.

[0072] Process Six: The treated natural gas enters the dehydrogenation unit 7 for dehydrogenation treatment. The dehydrogenation adopts a catalytic oxidation scheme. The dehydrogenation unit 7 uses a multi-stage catalytic oxidation reactor (1 - 4 stages), and the outlet temperature of each stage of the reactor is less than 200°C. After the reaction, the reactor is cooled to 20 - 50°C using an air cooler or a water cooler. After dehydrogenation treatment, the hydrogen concentration in the treated natural gas can be reduced to ≤1 ppm. The treated natural gas after dehydrogenation then enters the pressure swing adsorption unit 8.

[0073] Process Seven: The process natural gas enters the pressure swing adsorption unit 8 for helium purification. For example, the pressure swing adsorption process (with the pressure controlled at 1000 kPa.a to 3000 kPa.a) is adopted to refine the helium in the process natural gas, obtaining industrial helium with a concentration of 99.9% or above. This part of the purified industrial helium enters the cryogenic refining unit 9. At the same time, the desorbed gas from the pressure swing adsorption is transported to the first-stage membrane booster unit 2 through the pipeline connecting the pressure swing adsorption unit 8 and the input port of the first-stage membrane booster unit 2 to form a helium concentration and purification cycle.

[0074] Process Eight: The process natural gas enters the cryogenic refining unit 9 for further helium purification. For example, the cryogenic adsorption separation and purification process (with the pressure of 1.0 to 20 MPa.a) is adopted. The adsorption process is carried out under liquid nitrogen (-196°C). The process natural gas passing through the pressure swing adsorption unit 8 enters the cryogenic adsorption cylinder. By utilizing the adsorption characteristics of the adsorbent in this low-temperature environment, the remaining impurity components in the process natural gas are adsorbed, and the helium purity is increased to 99.999% or above. Finally, the obtained high-purity helium is transported to the helium storage unit 10 for storage.

[0075] Based on the same inventive concept, the embodiment of the present invention also provides a method for helium extraction by membrane separation technology. Since the principle of this method is similar to that of the aforementioned integrated device for helium extraction by membrane separation technology, the implementation of this method can refer to the implementation of the aforementioned device, and the repeated parts will not be elaborated.

[0076] Obviously, those skilled in the art can make various changes to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these changes.

Claims

1. An integrated device for helium extraction using membrane separation technology, characterized in that, Comprising: a multi-stage membrane treatment unit, a decarbonization unit, a dehydration unit, a dehydrogenation unit, a purification unit, and a helium storage unit; the multi-stage membrane treatment unit, the decarbonization unit, the dehydration unit, the dehydrogenation unit, the purification unit, and the helium storage unit are sequentially connected through pipelines; the membrane treatment unit includes a membrane separation unit and a membrane boosting unit; the membrane separation unit is used for concentrating helium in natural gas; the membrane boosting unit is used for boosting the permeate gas passing through the membrane separation unit; the decarbonization unit is used for removing carbon dioxide from natural gas; The purification unit includes a pressure swing adsorption unit and a cryogenic refining unit; the pressure swing adsorption unit is used to remove impurity gases in the crude helium; the cryogenic refining unit is used to adsorb the remaining impurity components after passing through the pressure swing adsorption unit 。 2. The device according to claim 1, characterized in that, the multi-stage membrane treatment unit includes: a primary membrane treatment unit and a secondary membrane treatment unit; the primary membrane separation unit, the primary membrane boosting unit, the decarbonization unit, the dehydration unit, the secondary membrane separation unit, the secondary membrane boosting unit, the dehydrogenation unit, the pressure swing adsorption unit, the cryogenic purification unit, and the helium storage unit are sequentially connected through pipelines; the input port of the primary membrane separation unit is used for connecting to the external raw material natural gas pipeline network.

3. The device according to claim 2, characterized in that, the primary membrane separation unit is also connected to the external raw material natural gas pipeline network, and is used for transporting the non-permeate gas separated by the primary membrane separation unit back to the raw material natural gas pipeline network.

4. The device according to claim 2, wherein the input port of the decarbonization unit is also connected to the raw material natural gas pipeline network through a pipeline, and is used for directly receiving raw material natural gas from the raw material natural gas pipeline network.

5. The device according to claim 2, characterized in that, the secondary membrane separation unit is also connected to the input port of the primary membrane separation unit through a pipeline, and is used for transporting the non-permeate gas separated by the secondary membrane separation unit to the primary membrane separation unit.

6. The device according to claim 2, characterized in that, the secondary membrane separation unit is also connected to the input port of the primary membrane boosting unit through a pipeline, and is used for transporting a part of the permeate gas separated by the secondary membrane separation unit back to the primary membrane boosting unit.

7. The device according to claim 2, wherein the pressure swing adsorption unit is also connected to the input port of the primary membrane boosting unit through a pipeline, and is used for transporting the desorbed gas after pressure swing adsorption back to the primary membrane boosting unit.

8. The device according to any one of claims 1 to 7, characterized in that, the device further includes: a natural gas liquefaction unit, a liquefied natural gas storage unit, and a demethanation unit; the natural gas liquefaction unit and the demethanation unit are sequentially connected through pipelines between the dehydration unit and the dehydrogenation unit; the natural gas liquefaction unit has two output ports, one output port is connected to the liquefied natural gas storage unit, and the other output port is connected to the demethanation unit.

9. A method for separating, enriching, and extracting high-purity helium from helium in raw material natural gas by using an integrated device for helium extraction by membrane separation technology according to any one of claims 1-8.

10. The method according to claim 9, wherein, the primary membrane boosting unit boosts the permeate gas passing through the primary separation membrane to 2000 kPa.a to 7000 kPa.a; the secondary membrane boosting unit boosts the permeate gas passing through the secondary separation membrane to 1000 kPa.a to 3000 kPa.a.

11. The method according to claim 9, wherein the dehydrogenation unit reduces the hydrogen content to ≤1 ppm.

12. The method according to claim 9, characterized in that, the pressure swing adsorption unit increases the helium purity to 99.9% and above; the cryogenic purification unit increases the helium purity to 99.999% and above.

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