Membrane separation oxygen-enriched equipment, oxygen-enriched gas supply system and oxygen-enriched combustion method

Abstract

The present invention discloses a membrane separation oxygen enrichment device, an oxygen-enriched gas supply system, and an oxygen-enriched combustion method. The membrane separation oxygen enrichment device of the present invention improves the oxygen enrichment effect of simple membrane separation by adding a magnetic field outside the membrane separation oxygen enrichment device, coordinating with a magnetic medium filled in the middle of the membrane material, utilizing the different paramagnetism and diamagnetic properties of oxygen molecules and nitrogen molecules, and relying on the mutual cooperation of the magnetic field and the magnetic medium. The oxygen-enriched combustion gas supply system of the present invention selects CO2-rich flue gas as the purge gas of the membrane separation component, directly realizing the mixed combustion of CO2-rich flue gas and O2-rich gas, solving the problems of low oxygen enrichment efficiency of the existing magnetic method and difficulty of oxygen escaping from the enrichment magnetic field. The entire oxygen-enriched gas supply process is continuous and stable.

Description

Technical Field

[0001] The present invention belongs to the technical field of heating furnaces, and relates to a technology and method for energy conservation, emission reduction and carbon reduction of heating furnaces, and in particular to a system and method for achieving energy conservation, emission reduction and carbon reduction of heating furnaces by utilizing oxygen-enriched combustion. Background Art

[0002] Oxygen-enriched combustion is a highly efficient and energy-saving combustion technology that involves combustion using oxygen-enriched air with a higher oxygen concentration than air. Compared to combustion with ordinary air, oxygen-enriched combustion can effectively increase flame temperature, improve heat utilization, and reduce exhaust losses. Furthermore, with the continuous development of oxygen-enriched preparation technology, oxygen-enriched combustion technology is becoming increasingly widely used and has been gradually extended to pulverized coal boilers, circulating fluidized beds, and industrial heating furnaces. Oxygen-enriched combustion can also achieve carbon capture during the combustion process. Combustion technology that provides oxygen-enriched gas while assisting with flue gas recirculation can produce high-concentration CO2-rich flue gas, achieving carbon enrichment. This reduces the scale, investment, and operating costs of post-combustion carbon capture equipment, allowing for CO2 recovery or resource utilization at a lower cost. It has many advantages, including relatively low cost, ease of scalability, and the ability to transform existing units. It is considered one of the most likely CCUS technologies to be widely promoted and commercialized.

[0003] The cost of oxygen enrichment is a key factor influencing the overall investment and operating expenses of oxygen-enriched combustion technology. Current oxygen enrichment technologies primarily include cryogenic separation, pressure swing adsorption (PSA), membrane separation, and magnetic oxygen enrichment. Cryogenic separation utilizes the differences in boiling points between liquefied components for distillation and separation. This mature process produces high-purity oxygen, but it consumes significant energy. It is primarily used for CO2 capture in large-scale pure oxygen combustion. Pressure swing adsorption (PSA) utilizes the adsorbent's ability to adsorb and desorb specific gases to separate gases. It can be used for medium- and small-scale gas separation, but typically requires two or more tanks for switching between adsorption and regeneration operations. This can lead to issues such as frequent valve actuation, leakage, and high malfunctions, as well as high regeneration energy consumption. Membrane separation technology utilizes membrane materials with specialized selective separation properties to separate air under a specific pressure. It features a simple process, compact size, and low energy consumption, making it suitable for medium- and small-scale, low-purity oxygen production. The key to membrane technology is the production of membrane materials with high flux, high selectivity, long service life, and ease of cleaning. Magnetic oxygen enrichment utilizes the different paramagnetism and diamagnetic properties of oxygen and nitrogen molecules to cause the two gas molecules to be deflected in different directions through a high magnetic field to obtain oxygen-enriched air and nitrogen-enriched air. It has the advantages of low energy consumption and low oxygen enrichment cost. However, existing magnetic oxygen enrichment devices generally have problems such as low efficiency, low oxygen enrichment concentration, small oxygen enrichment volume, and difficulty in oxygen escaping from the enrichment magnetic field.

[0004] CN104271217A discloses an oxygen separator and a method for producing oxygen, which utilizes an oxygen separation adsorbent to realize the oxygen separation process through multi-cycle continuous operation. This technology requires multiple groups of oxygen separators to switch and operate in order to realize continuous oxygen supply, and can only provide a small amount of oxygen supply. Patent CN101450792A discloses a method for separating air to produce oxygen and nitrogen. The entire process is carried out on a platform composed of a mixed conductor oxygen-permeable ceramic membrane separator and a pressure swing adsorption separator with a complex metal oxide as an oxygen adsorbent. The separation of nitrogen and oxygen in the air is achieved through two steps of osmosis and pressure swing adsorption. The system is complex, has high requirements on the performance of the membrane material, and requires frequent switching of vacuum regeneration. The regeneration process requires the adsorbent to desorb and penetrate the membrane material, and the system energy consumption is high. Patent CN101857200A uses magnetic separation technology to disclose a new type of combined magnetic oxygen enrichment device. The oxygen enrichment device adopts three-stage series oxygen enrichment to gradually improve the oxygen purity, but there is a problem that oxygen is difficult to separate from the magnetic field during actual operation.

[0005] In addition, under oxygen-enriched combustion conditions, as the volume fraction of oxygen increases, the flame temperature rises, more thermal nitrogen oxides will be generated, resulting in an increase in the concentration of nitrogen oxides in the flue gas, which to a certain extent restricts the promotion and application of oxygen-enriched combustion. Therefore, in the process of oxygen-enriched combustion, it is very important to adopt appropriate low-nitrogen emission reduction technology. Patent CN103343965A discloses a heating furnace system using oxygen-enriched combustion. The invention relates to a heating furnace system in which air and oxygen are pre-mixed and then supplied to a burner. The use of oxygen-enriched combustion technology can achieve the effective utilization of low calorific value coal gas, which is more efficient, energy-saving, and environmentally friendly. However, it is necessary to convert all the burners of the original heating system into oxygen-enriched burners before it can be used, and the investment cost is relatively high. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the present invention proposes a membrane separation oxygen enrichment device, an oxygen-enriched gas supply system, and an oxygen-enriched combustion method. The oxygen enrichment device and oxygen-enriched gas supply system of the present invention can efficiently and cost-effectively provide a large amount of oxygen-enriched gas for oxygen-enriched combustion. They can also reduce and control nitrogen oxide emissions at the source, improve the thermal efficiency of the heating furnace, reduce flue gas emissions, recover waste heat from the flue gas, and simultaneously enrich the CO2 concentration in the flue gas, facilitating subsequent CO2 capture and recovery.

[0007] To achieve the above-mentioned object, the first aspect of the present invention provides a membrane separation oxygen enrichment device, wherein the membrane separation device is a magnetic-membrane combined separation device.

[0008] A magnetic-membrane combined separation device comprises an outer shell, an intermediate cavity, a permeate cavity, a membrane separation component and a magnetic field component;

[0009] The permeate cavity is located at one end of the outer shell, and the middle cavity is arranged adjacent to it;

[0010] The membrane separation component is arranged in the middle cavity within the outer shell, and the open end is connected to the permeate cavity; the membrane separation component divides the middle cavity into a residual channel and a permeate channel, wherein the hollow cavity of the membrane separation component and the permeate cavity form the permeate channel;

[0011] The permeate gas cavity is provided with a permeate gas outlet, and the two sides of the outer shell are respectively provided with a raw gas inlet and a residual gas outlet;

[0012] The magnetic field assembly is arranged around or on both sides of the outer shell of the membrane separation oxygen enrichment device, and is used to form a magnetic field in the shell area of ​​the membrane separation device;

[0013] The middle permeation channel of the membrane separation component is filled with magnetic concentrating medium.

[0014] Furthermore, the membrane separation components are arranged in multiple groups, and the multiple groups of membrane separation components and the permeate gas cavity form multiple groups of permeate channels.

[0015] Furthermore, the membrane separation component is in the form of a hollow tubular single-opening membrane, that is, one end is closed and the other end is open.

[0016] Furthermore, the feed gas inlet and the residual gas outlet are arranged on both sides of the shell near the two end portions and are communicated with the residual gas channel of the membrane separation component.

[0017] Furthermore, the magnetic field assembly is composed of multiple groups of magnets, which can be permanent magnets, electromagnets or superconducting magnets.

[0018] Furthermore, the membrane separation assembly tube wall is formed of a membrane separation material. The membrane separation material exhibits excellent selective permeability for oxygen and slower nitrogen permeability relative to oxygen, with the membrane material exhibiting an O2 / N2 selectivity greater than 2 (i.e., the ratio of the permeation rates of O2 to N2). The membrane separation material may be a natural membrane material, an inorganic membrane material, a polymer membrane material, or a composite membrane material.

[0019] Furthermore, the magnetic concentrating medium is a material capable of converting a uniform magnetic field into a high-gradient non-uniform magnetic field. The magnetic concentrating medium can be one or a combination of a ball medium, a toothed plate medium, a mesh medium, a rod medium, or a steel wool medium, and can be made of one or more of pure iron, low-carbon steel, ferritic magnetic stainless steel, and an iron-cobalt-neodymium-boron alloy.

[0020] Furthermore, the membrane separation oxygen enrichment equipment has a feed gas inlet, a permeate gas outlet, and a residue gas outlet. The feed gas inlet and the residue gas outlet are connected to the residue channel of the membrane separation component, and the permeate gas outlet is connected to the permeate channel of the membrane separation component.

[0021] The membrane separation oxygen enrichment equipment of the present invention can be used to provide oxygen-enriched combustion-supporting air for oxygen-enriched combustion systems, and can also be used to supply oxygen-enriched gas in metal smelting, environmental protection treatment of wastewater and exhaust gas, chemical synthesis oxidation reaction, engine oxygenation, medical care oxygen supply, aquaculture and other fields.

[0022] A second aspect of the present invention provides an oxygen-enriched gas supply system, which includes the membrane separation oxygen-enriched equipment described above.

[0023] An oxygen-enriched air supply system, the system includes an air filter, a combustion-supporting induced draft fan, a membrane separation oxygen-enriching device, a mixer, a heat exchanger, a combustion furnace, a flue gas circulation fan, and a dehydration tank; the air filter inlet is connected to the atmosphere; the air filter outlet is connected to the raw gas inlet of the membrane separation oxygen-enriching device; the permeate gas outlet of the membrane separation device is connected to the combustion-supporting induced draft fan inlet, and the intercepted gas outlet of the membrane separation oxygen-enriching device is connected to the atmosphere; the combustion-supporting induced draft fan outlet is connected to the mixer inlet; the other inlet of the mixer is connected to the dehydration tank outlet pipeline, and the mixer outlet is connected to the combustion-supporting air inlet of the gas furnace via a heat exchanger; the combustion furnace flue gas outlet is connected to the flue gas circulation fan inlet via a heat exchanger; the flue gas circulation fan outlet is divided into two paths, the first path is connected to the dehydration tank inlet, and the second path is discharged to the outside of the system; the dehydration tank outlet pipeline is connected to the mixer inlet.

[0024] Furthermore, the dehydration tank is a cooling dehydration gas-liquid separation tank, and a refrigerant heat extraction facility is provided inside.

[0025] Furthermore, the heat exchanger is an air-air heat exchanger, and the form of the heat exchanger is not limited.

[0026] Furthermore, the combustion furnace may be a combustion furnace for solid fuel, liquid fuel or gas fuel, and the combustion furnace has a fuel supply port, a combustion air supply port and a flue gas exhaust pipeline.

[0027] The third aspect of the present invention also provides an oxygen-enriched combustion method, in which the above-mentioned system is applied.

[0028] An oxygen-enriched combustion method comprises the following steps:

[0029] (1) Air is introduced into the membrane separation oxygen enrichment device by the combustion-supporting induced draft fan for treatment. In the membrane separation oxygen enrichment device, oxygen has a higher membrane permeability and is enriched in the permeation channel, while nitrogen has a lower membrane permeability and is enriched in the interception channel. The oxygen-enriched gas is led out of the membrane separation device by the combustion-supporting induced draft fan through the permeation channel, and the nitrogen in the interception channel is discharged to the outside of the system;

[0030] (2) The oxygen-rich gas drawn out by the combustion-supporting induced draft fan in step (1) enters the mixer and is mixed with the CO2-rich flue gas treated in the dehydration tank. The mixed gas is heat-exchanged and then enters the combustion furnace as combustion-supporting air to be burned with the fuel. The high-temperature flue gas generated after the combustion is heat-exchanged and heat is recovered, and then pressurized by the flue gas circulation fan. The pressurized high-temperature flue gas is divided into two paths: the first path enters the dehydration tank for cooling and dehydration, and the second path is discharged out of the system;

[0031] (3) The low-temperature flue gas treated in the dehydration tank in step (2) enters the mixer and is mixed with the oxygen-rich gas and used as combustion-supporting air.

[0032] Furthermore, an air filter is provided before the membrane separation oxygen enrichment device in step (1) to filter impurities in the air.

[0033] Furthermore, the low-temperature flue gas after treatment in the dehydration tank in step (2) is a flue gas rich in CO2, and the volume concentration of CO2 in the flue gas is higher than 20%.

[0034] Furthermore, the gas discharged from the permeation channel of the membrane separation oxygen-enriching equipment in step (1) is oxygen-enriched gas (i.e., combustion-supporting air), and the volume concentration of O2 in the combustion-supporting air is 30% to 60%.

[0035] Furthermore, the temperature of the dehydration tank in step (2) is 10-60°C, preferably 25-40°C.

[0036] Furthermore, in step (2), the high-temperature flue gas is divided into two paths after being pressurized by the circulating fan, the first path accounts for 10% to 60% of the total high-temperature flue gas, and the second path accounts for 40% to 90% of the total high-temperature flue gas.

[0037] Furthermore, the high-temperature flue gas discharged from the second external discharge system in step (2) is CO2-rich flue gas, which is further subjected to carbon capture or recovery treatment.

[0038] Furthermore, the oxygen-enriched combustion method of the present invention is applicable to oxygen-enriched combustion processes of various types of combustion furnaces using solid fuel, liquid fuel and gas fuel.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] 1. A membrane separation oxygen enrichment device was proposed. This device incorporates a magnetic field external to the membrane separation oxygen enrichment device. This, combined with a magnetic concentrator filled between the membrane materials, leverages the differing paramagnetic and diamagnetic properties of oxygen and nitrogen molecules. The interaction between the magnetic field and the magnetic concentrator significantly enhances the oxygen enrichment efficiency of simple membrane separation. Furthermore, an induced draft fan is used to promptly extract the oxygen-enriched gas from the device (magnetic field area), addressing the low efficiency of existing magnetic oxygen enrichment methods and the difficulty of oxygen escaping the enrichment magnetic field. The entire oxygen enrichment process remains continuous and stable.

[0041] 2. Membrane separation and oxygen enrichment are used to separate nitrogen and oxygen from the air. The separation of nitrogen reduces the amount of combustion-supporting air, thereby reducing the amount of flue gas generated, reducing the heat loss of flue gas, improving the thermal efficiency of the heating furnace, and reducing the generation of nitrogen oxides from raw materials, thereby reducing and controlling nitrogen oxide emissions from the source; combined with the recycling and regeneration of CO2-rich flue gas and mixing it with oxygen-rich gas, it is equivalent to using CO2 instead of N2 as a diluent gas, which greatly increases the concentration of CO2 in the flue gas and significantly reduces the cost of carbon capture, providing convenient conditions for subsequent CO2 capture and recovery. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 This is a structural schematic diagram of an oxygen-enriched gas supply system of the present invention.

[0043] In the figure, 1-air pipeline, 2-filter, 3-combustion-supporting draft fan, 4-heat exchanger, 5-combustion furnace, 6-flue gas circulation fan, 7-membrane separation oxygen enrichment equipment, 8-burner, 9-fuel supply, 10-dehydration tank, 11-circulation fan first outlet, 12-circulation fan second outlet, 13-combustion-supporting air inlet, 14-combustion furnace flue gas outlet, 15-carbon capture and recovery device, 16-intercepted gas exhaust pipeline, 17-mixer.

[0044] Figure 2 It is a structural schematic diagram of the membrane separation oxygen enrichment equipment of the present invention.

[0045] In the figure, 51-outer shell, 52-intermediate cavity, 53-permeate gas cavity, 54-membrane separation component, 55-magnetic field component, 56-feed gas inlet, 58-intercepted gas outlet, 59-permeate gas outlet, 60-intercepted channel, 61-permeate channel.

[0046] Figure 3 Schematic diagram of the structure of the membrane separation component of the present invention.

[0047] In the figure, 62 is a magnetic medium, and 63 is a membrane separation material. DETAILED DESCRIPTION

[0048] The membrane separation oxygen-enriching device, oxygen-enriched gas supply system and oxygen-enriched combustion method of the present invention are described in detail below with reference to the accompanying drawings and examples, but the present invention is not limited thereto.

[0049] Example 1

[0050] This embodiment describes the membrane separation oxygen enrichment equipment in detail. Figure 2As shown, the membrane separation oxygen enrichment device of the present invention includes an outer shell 51, an intermediate cavity 52, a permeate cavity 53, a membrane separation component 54 and a magnetic field component 55. The permeate cavity 53 is located at one end of the outer shell 51. The membrane separation component 54 is a hollow tube type single opening membrane, that is, one end of the hollow membrane tube is closed and the other end is open. The membrane separation component 54 is arranged in the intermediate cavity 52 in the outer shell, and the open end is connected to the permeate cavity 53. The membrane separation component 54 divides the intermediate cavity into a residual channel 60 and a permeate channel 61, wherein the membrane separation The middle cavity of the separation component 54 and the permeate gas cavity 53 form a permeate channel. The membrane separation component 54 is arranged in multiple groups, forming multiple groups of permeate channels 61 with the permeate gas cavity 53. The permeate gas cavity 53 is provided with a permeate gas outlet 59. The two sides of the outer shell are respectively provided with a raw gas inlet 56 and a residual gas outlet 58. The raw gas inlet 56 and the residual gas outlet 58 are arranged near the two end positions on both sides of the shell 51 and are connected to the residual channel 60 of the membrane separation component. The magnetic field component 55 is arranged around or on both sides of the outer shell 51 of the membrane separation oxygen enrichment equipment.

[0051] like Figure 3 As shown, the structure of the membrane separation component of the system and method of the present invention is as follows: the tube wall of the membrane separation component 54 is a membrane separation material 63, and the middle channel of the membrane separation component is filled with a magnetic medium 62.

[0052] Example 2

[0053] This embodiment describes the oxygen-enriched combustion gas supply system of the present invention in detail.

[0054] like Figure 1 As shown, the present invention provides an oxygen-enriched air supply system, which includes an air filter 2, a combustion-supporting fan 3, a membrane separation oxygen-enriching device 7, a heat exchanger 4, a combustion furnace 5, a flue gas circulation fan 6, a dehydration tank 10, and a mixer 17; the inlet of the air filter 2 is connected to the atmosphere; the outlet of the air filter 2 is connected to the raw gas inlet of the membrane separation oxygen-enriching device 7; the permeate outlet of the membrane separation oxygen-enriching device 7 is connected to the inlet of the combustion-supporting induced draft fan 3, and the intercepted gas outlet of the membrane separation oxygen-enriching device 7 is discharged to the atmosphere ; The outlet of the combustion-supporting induced draft fan 3 is connected to the inlet of the mixer 17; the other inlet of the mixer 17 is connected to the outlet pipeline of the dehydration tank 10, and the outlet of the mixer 17 is connected to the combustion-supporting air inlet 13 of the gas furnace via the heat exchanger 4; the flue gas outlet 14 of the combustion furnace is connected to the inlet of the flue gas circulation fan 6 via the heat exchanger 4; the outlet of the flue gas circulation fan is divided into two routes, the first route 11 is connected to the inlet of the dehydration tank 10, and the second route 12 is discharged outside the system; the outlet pipeline of the dehydration tank 10 is connected to the inlet of the mixer 17.

[0055] Example 3

[0056] This embodiment describes the oxygen-enriched combustion gas supply method of the present invention in detail. Figure 1-3 The working process of an oxygen-enriched gas supply system and an oxygen-enriched combustion method provided by the present invention is as follows: air is introduced into the membrane separation oxygen-enriching device 7 by the combustion-supporting induced draft fan 3 for treatment. In the membrane separation oxygen-enriching device 7, oxygen with higher membrane permeability is enriched in the permeation channel 61, and nitrogen with lower membrane permeability is enriched in the interception channel 60. The oxygen-enriched gas is led out of the membrane separation oxygen-enriching device 7 by the combustion-supporting induced draft fan 3 through the permeation channel, and the nitrogen in the interception channel is discharged to the outside of the system 16; the oxygen-enriched gas led out by the combustion-supporting induced draft fan 3 enters the mixer 17 and is mixed with the CO2-rich flue gas treated by the dehydration tank 10. After the mixture is heat-exchanged, it enters the combustion furnace 5 as combustion-supporting air and is burned with fuel. The high-temperature flue gas 14 generated after combustion is heat-exchanged and heat-recovered, and is pressurized by the flue gas circulation fan 6 and divided into two paths: the first path 11 enters the dehydration tank 10 for cooling and dehydration treatment, and the treated low-temperature flue gas enters the mixer and is mixed with the oxygen-enriched gas to be used as combustion-supporting air; the second path is discharged to the outside of the system and can be further carbon captured or recovered.

[0057] Example 4

[0058] This embodiment provides a specific application case of an oxygen-enriched gas supply system and an oxygen-enriched combustion method.

[0059] use Figure 1 The magnetic oxygen-enriched gas supply combustion system shown in the figure is used to carry out oxygen-enriched combustion treatment on an 8MW gas heating furnace of a certain enterprise. The fuel gas is natural gas and the membrane separation equipment adopts Figure 2 As shown, the membrane material is polytrimethylsilyl propyne / polycarbonate polymer nitrogen / oxygen separation membrane, the magnetic medium in the membrane separation component is 1mm steel mesh medium, the external magnetic field is an electromagnet, the external magnetic field strength is >5T, and the magnetic field gradient is >2000T / m.

[0060] After being pressurized by the combustion-supporting blower 3, the air enters the membrane separation oxygen enrichment device 7 for treatment. In the membrane separation oxygen enrichment device 7, oxygen has a higher membrane permeability and is enriched in the permeation channel, while nitrogen has a lower membrane permeability and is enriched in the interception channel. At the same time, CO2-rich flue gas (CO2 volume fraction of about 24%) enters the permeation channel of the membrane separation oxygen enrichment device 7 from the purge gas inlet as a purge gas, and is discharged from the membrane separation device through the permeation channel together with the oxygen-rich gas. At this time, the volume fractions of the components of the combustion-supporting air are: O2 is about 24%, N2 is about 57%, CO2 is about 11%, and the rest is The nitrogen in the interception channel is discharged to the system 16; the oxygen-rich gas discharged from the permeation channel of the membrane separation oxygen-enriched device 7 enters the combustion furnace 5 as combustion-supporting air after heat exchange and burns with the fuel. The high-temperature flue gas 14 generated after combustion is subjected to heat exchange to recover heat, and is then pressurized by the flue gas circulation fan 6 and divided into two paths: the first path accounts for 48% of the total flue gas volume and enters the dehydration tank 16 for cooling and dehydration treatment, and then enters the membrane separation device 7 as a purge gas. The second path is the remaining flue gas discharge system. The CO2 volume concentration in the exhaust gas is about 24%, which can be further carbon captured or recovered.

[0061] The above process uses membrane separation oxygen enrichment combined with flue gas circulation purge process optimization. Without modifying the original heating furnace burner, it reduces flue gas generation, reduces exhaust heat loss, improves the thermal efficiency of the heating furnace, and can effectively control nitrogen oxide emissions. Compared with the air-assisted combustion process, the overall thermal efficiency of the combustion furnace is increased by more than 1%, the flue gas emission volume is reduced by 54%, and the CO2 concentration in the flue gas is increased from about 10% to 24%, which is equivalent to reducing the scale of subsequent carbon capture equipment by more than 50%, greatly reducing the cost of carbon capture and providing convenient conditions for subsequent CO2 capture and recovery.

Claims

1. A membrane separation oxygen enrichment device, characterized in that: The membrane separation oxygen enrichment equipment comprises an outer shell, an intermediate cavity, a permeate cavity, a membrane separation component and a magnetic field component; The permeate cavity is located at one end of the outer shell, and the middle cavity is arranged adjacent to it; The membrane separation component is a hollow tubular single-opening membrane, and the membrane separation component is arranged in the middle cavity in the outer shell, and the open end is connected to the permeate cavity; The membrane separation component divides the intermediate cavity into a residual channel and a permeate channel, wherein the cavity in the membrane separation component and the permeate cavity form a permeate channel; The permeate gas cavity is provided with a permeate gas outlet, and the two sides of the outer shell are respectively provided with a raw gas inlet and a residual gas outlet; The magnetic field assembly is arranged around or on both sides of the outer shell of the membrane separation device, and is used to form a magnetic field in the shell area of ​​the membrane separation device; The permeation channel of the membrane separation component is filled with magnetic concentrating medium.

2. The membrane separation oxygen enrichment device according to claim 1, characterized in that: The membrane separation components are arranged in multiple groups, and the multiple groups of membrane separation components and the permeate gas cavity form multiple groups of permeate gas channels.

3. The membrane separation oxygen enrichment device according to claim 1, characterized in that: The raw gas inlet and the intercepted gas outlet are arranged on both sides of the shell near the two end portions and are communicated with the intercepted gas channel of the membrane separation component.

4. The membrane separation oxygen enrichment device according to claim 1, characterized in that: The magnetic field assembly is composed of multiple groups of magnets, and the magnets are permanent magnets, electromagnets or superconducting magnets.

5. The membrane separation oxygen enrichment device according to claim 1, characterized in that: The tube wall of the membrane separation component is made of membrane separation material, and the selectivity of the membrane separation material to O2 / N2 is greater than 2.

6. The membrane separation oxygen enrichment device according to claim 1, characterized in that: The magnetic concentrating medium is a substance used to convert a uniform magnetic field into a high-gradient non-uniform magnetic field.

7. The membrane separation oxygen enrichment device according to claim 6, characterized in that: The magnetic concentrating medium is one or a combination of ball medium, tooth plate medium, mesh medium, rod medium, and steel wool medium. The material of the magnetic concentrating medium is one or more of pure iron, low carbon steel, ferrite magnetic stainless steel, and iron-cobalt-neodymium-boron alloy.

8. The membrane separation oxygen enrichment device according to claim 1, characterized in that: The feed gas inlet and the residual gas outlet are communicated with the residual gas channel of the membrane separation component, and the permeate gas outlet is communicated with the permeate channel of the membrane separation component.

9. An oxygen-enriched gas supply system, characterized in that: The invention comprises the membrane separation oxygen enrichment equipment according to any one of claims 1 to 8.

10. The oxygen-enriched gas supply system according to claim 9, characterized in that: The system includes an air filter, a combustion-supporting induced draft fan, a membrane separation oxygen-enriching device, a mixer, a heat exchanger, a combustion furnace, a flue gas circulation fan, and a dehydration tank; the air filter inlet is connected to the atmosphere; the air filter outlet is connected to the raw gas inlet of the membrane separation device; the permeate gas outlet of the membrane separation oxygen-enriching device is connected to the combustion-supporting induced draft fan inlet, and the intercepted gas outlet of the membrane separation oxygen-enriching device is discharged to the atmosphere; the combustion-supporting induced draft fan outlet is connected to the mixer inlet; the other inlet of the mixer is connected to the dehydration tank outlet pipeline, and the mixer outlet is connected to the combustion-supporting air inlet of the gas furnace via a heat exchanger; the flue gas outlet of the combustion furnace is connected to the flue gas circulation fan inlet via a heat exchanger; the flue gas circulation fan outlet is divided into two paths, the first path is connected to the dehydration tank inlet, and the second path is discharged to the outside of the system; the dehydration tank outlet pipeline is connected to the mixer inlet.

11. The oxygen-enriched gas supply system according to claim 10, characterized in that: The dehydration tank is a cooling and dehydration gas-liquid separation tank, and a refrigerant heat extraction facility is provided inside the tank.

12. An oxygen-enriched combustion method, characterized in that: The oxygen-enriched gas supply system according to any one of claims 10-11 is applied.

13. The oxygen-enriched combustion method according to claim 12, characterized in that: The steps include: (1) Air is introduced into the membrane separation oxygen enrichment device by the combustion-supporting induced draft fan for treatment. In the membrane separation oxygen enrichment device, oxygen has a higher membrane permeability and is enriched in the permeation channel, while nitrogen has a lower membrane permeability and is enriched in the interception channel. The oxygen-enriched gas is led out of the membrane separation device by the combustion-supporting induced draft fan through the permeation channel, and the nitrogen in the interception channel is discharged to the outside of the system; (2) The oxygen-rich gas drawn out by the combustion-supporting induced draft fan in step (1) enters the mixer and is mixed with the CO2-rich flue gas treated in the dehydration tank. The mixed gas is heat-exchanged and then enters the combustion furnace as combustion-supporting air to be burned with the fuel. The high-temperature flue gas generated after the combustion is heat-exchanged and heat is recovered, and then pressurized by the flue gas circulation fan. The pressurized high-temperature flue gas is divided into two paths: the first path enters the dehydration tank for cooling and dehydration, and the second path is discharged out of the system; (3) The low-temperature flue gas treated in the dehydration tank in step (2) enters the mixer and is mixed with the oxygen-rich gas and used as combustion-supporting air.

14. The oxygen-enriched combustion method according to claim 13, characterized in that: In step (1), an air filter is provided before the membrane separation oxygen enrichment device to filter impurities in the air.

15. The oxygen-enriched combustion method according to claim 13, characterized in that: The low-temperature flue gas after treatment in the dehydration tank in step (2) is a flue gas rich in CO2, and the volume concentration of CO2 in the flue gas is higher than 20%.

16. The oxygen-enriched combustion method according to claim 13, characterized in that: The volume concentration of O2 in the oxygen-enriched gas discharged from the permeation channel of the membrane separation oxygen-enriched equipment in step (1) is 30% to 60%.

17. The oxygen-enriched combustion method according to claim 13, characterized in that: The temperature of the dehydration tank in step (2) is 10-60°C.

18. The oxygen-enriched combustion method according to claim 13, characterized in that: In step (2), the first flue gas accounts for 10% to 60% of the total high-temperature flue gas, and the second flue gas accounts for 40% to 90% of the total high-temperature flue gas.

19. The oxygen-enriched combustion method according to claim 13, characterized in that: In step (2), the high-temperature flue gas discharged from the second exhaust system is subjected to carbon capture or recovery treatment.

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