A coal-to-hydrogen carbon capture system based on methane steam reforming and its operation method

Abstract

This invention discloses a coal-to-hydrogen carbon capture system and its operation method based on methane steam reforming. The system mainly includes a feedwater pump, heat exchangers, a gasification reactor, a gas-liquid separator, a regenerator, a reforming reactor, a shift reactor, and a pressure swing adsorption (PSA) device. Based on supercritical water gasification technology, this invention achieves high-yield hydrogen production and complete carbon capture of carbon dioxide through methane steam reforming and water-gas shift reactions. The system's gasification syngas is rationally diverted to effectively preheat the gasification feedwater and reforming feedwater, reducing the heat exchange temperature difference between the hot and cold ends of the heat exchangers and achieving efficient matching of system waste heat. This invention also reheats the reforming reaction gas, reducing the system's heat requirements from the outside environment and matching the operating conditions of the subsequent water-gas shift reaction. By adjusting the feedwater flow rate of the reforming reaction, the system promotes methane steam reforming and water-gas shift reactions, increasing the system's hydrogen production capacity and improving its hydrogen production efficiency.

Description

Technical Field

[0001] This invention relates to the field of efficient and low-carbon hydrogen production technology from coal, specifically to a coal-to-hydrogen carbon capture system and its operation method based on methane steam reforming. Background Technology

[0002] Hydrogen, as a promising clean fuel and a high-quality alternative to fossil fuels, is widely used in chemical synthesis, fuel cells, and combined cycle systems. Currently, hydrogen production mainly comes from coal gasification, natural gas reforming, and water electrolysis. Due to economic costs and technological maturity limitations in water electrolysis, large-scale hydrogen production technologies primarily use coal and natural gas as raw materials. Among these, hydrogen produced through coal gasification accounts for approximately 18% of the world's total hydrogen production.

[0003] Supercritical water gasification technology can convert the chemical energy of coal into hydrogen-rich syngas, offering advantages such as low gasification temperature, high hydrogen production rate, clean syngas, and easy carbon capture. It is a highly efficient and feasible method for producing hydrogen from solid coal. Supercritical water gasification is gradually becoming one of the alternative methods for large-scale hydrogen production. Achieving efficient, clean, and low-carbon conversion of coal, and further obtaining high-yield hydrogen production from systems, is the core key to promoting the development of the national hydrogen energy industry. Summary of the Invention

[0004] To achieve efficient, clean, and low-carbon hydrogen production from coal, the present invention aims to propose a coal-based hydrogen production carbon capture system and its operation method based on methane steam reforming. The system is based on supercritical water gasification technology and achieves high-yield hydrogen production through methane steam reforming and water-gas shift reaction, thereby improving the system's hydrogen production efficiency and achieving efficient matching of system waste heat for complete carbon capture of carbon dioxide.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A coal-to-hydrogen carbon capture system based on methane steam reforming includes a gasification feedwater pump 1, a low-temperature preheater 2, a medium-temperature preheater 3, a high-temperature preheater 4, a gasification reactor 5, a throttle valve 6, a first gas-liquid separator 7, a regenerator 8, a reforming reactor 9, a shift reactor 10, a reforming feedwater pump 11, a first heater 12, a second heater 13, a cooler 14, a second gas-liquid separator 15, and a pressure swing adsorption device 16. The gasification feedwater, after passing through the gasification feedwater pump 1, is connected to the cold ends of the low-temperature preheater 2, the medium-temperature preheater 3, and the high-temperature preheater 4 in that order. The cold end outlet of the high-temperature preheater 4 is connected to the inlet of the gasification reactor 5; coal and oxygen are connected to the inlet of the gasification reactor 5 via pipelines; ash is discharged from the outlet of the gasification reactor 5 through the ash discharge pipeline; the syngas from the outlet of the gasification reactor 5 is connected to the hot ends of the high-temperature preheater 4, the medium-temperature preheater 3, and the low-temperature preheater 2 in sequence; the working fluid portion of the hot end outlet of the high-temperature preheater 4 is partially diverted to the hot end inlet of the second heater 13; the hot end outlet of the second heater 13 and the hot end outlet of the medium-temperature preheater 3 are both connected to the hot end inlet of the low-temperature preheater 2; the low-temperature preheater... The hot end outlet of unit 2 is connected to the inlet of unit 7 of gas-liquid separator 1 via throttle valve 6; the liquid phase outlet of unit 7 of gas-liquid separator 1 is water, and the working fluid at the gas phase outlet is connected to the cold end of regenerator 8; the reforming feedwater, after passing through reforming feedwater pump 11, is connected to the cold end inlets of unit 1 heater 12 and unit 2 heater 13, respectively, and the cold end outlet of unit 2 heater 13 is connected to the cold end inlet of regenerator 8; the gas phase outlet of unit 1 gas-liquid separator 7 and the cold end outlet of unit 2 heater 13, after passing through regenerator 8, are respectively connected to the inlet of reforming reactor 9; oxygen is connected to the reforming reactor 9 via pipeline. The inlet of reactor 9 is connected to the hot end inlet of regenerator 8, and the hot end outlet of regenerator 8 is connected to the inlet of shift reactor 10. The working medium at the outlet of shift reactor 10 is connected to the hot end inlet of heater 12. The hot end outlet of heater 12 is connected to the inlet of gas-liquid separator 15 after passing through cooler 14. The liquid phase outlet of gas-liquid separator 15 is water, and the working medium at the gas phase outlet is connected to the inlet of pressure swing adsorption device 16. High-purity hydrogen product is obtained at the outlet of pressure swing adsorption device 16, and the remaining carbon dioxide is completely captured.

[0007] The gasification reactor 5 operates at a temperature of 500℃-800℃, an operating pressure of 23MPa-30MPa, and a coal-water slurry concentration of 10%-40%.

[0008] The reforming reactor 9 operates at a temperature of 700℃-1200℃.

[0009] The operating temperature of the shift reactor 10 is 180℃-240℃.

[0010] The system's required heat is provided through a partial oxidation process of the fuel, achieving system self-heating balance. The oxygen entering the system is split into two streams: one stream enters the gasification reactor 5, where it undergoes a partial oxidation supercritical water gasification reaction with coal and water, releasing heat precisely to meet the heat required for the gasification reaction; the other stream enters the reforming reactor 9, where it undergoes a partial oxidation methane reforming reaction with syngas and water, releasing heat precisely to meet the heat required for the reforming reaction.

[0011] By rationally diverting the syngas at the hot end outlet of the high-temperature preheater 4, the gasification feedwater and reforming feedwater are effectively preheated. The minimum heat exchange temperature difference between the low-temperature preheater 2, the medium-temperature preheater 3, the high-temperature preheater 4 and the second heater 13 is 5℃-20℃.

[0012] The inlet temperature of the pressure swing adsorption device 16 is 20℃-40℃, and the inlet pressure is 0.8MPa-3MPa.

[0013] The operation method of the coal-to-hydrogen carbon capture system based on methane steam reforming is as follows: Gasification feedwater, after being pressurized by gasification feedwater pump 1, is preheated by passing through the cold ends of low-temperature preheater 2, medium-temperature preheater 3, and high-temperature preheater 4, before entering the gasification reactor 5. Coal and oxygen enter the gasification reactor 5, where a partially oxidized supercritical water gasification reaction occurs. Ash is discharged from the outlet of the gasification reactor 5, and syngas exits from the outlet of the gasification reactor 5, passing through the high-temperature preheater 4, medium-temperature preheater 3, and low-temperature preheater 2 in sequence. At the hot end, the gasification feedwater is preheated; the syngas from the hot end outlet of the high-temperature preheater 4 is partially diverted to the hot end inlet of the second heater 13 to preheat the reforming feedwater; after waste heat recovery, the syngas flows from the hot end outlet of the low-temperature preheater 2 through the throttle valve 6 to reduce its pressure, and then enters the first gas-liquid separator 7 for gas-liquid separation; by adjusting the feedwater flow rate into the reforming feedwater pump 11, the methane steam reforming reaction in the reforming reactor 9 and the water-gas shift reaction in the shift reactor 10 can be promoted, thereby increasing... The system's hydrogen production efficiency; after being pressurized by reforming feedwater pump 11, the reforming feedwater is preheated sequentially through the cold ends of heater 12 and heater 23; oxygen enters reforming reactor 9; the syngas from the gas phase outlet of gas-liquid separator 7 and the reforming feedwater from the cold end outlet of heater 23 enter regenerator 8 for heating, and then enter reforming reactor 9 respectively to undergo a partially oxidized methane reforming reaction; the reformed gas from the outlet of reforming reactor 9 enters shift reactor 10 after passing through the hot end of regenerator 8. A water-gas shift reaction occurs; the working fluid at the outlet of the shift reactor 10 passes through the hot end of the first heater 12 and the cooler 14, and then enters the second gas-liquid separator 15 for gas-liquid separation; the water at the liquid phase outlet of the second gas-liquid separator 15 is discharged through a pipeline, and the working fluid at the gas phase outlet includes hydrogen and carbon dioxide; the working fluid at the gas phase outlet of the second gas-liquid separator 15 enters the pressure swing adsorption device 16 for hydrogen separation and purification, and high-purity hydrogen product is obtained at the outlet of the pressure swing adsorption device 16, while the remaining carbon dioxide is completely captured.

[0014] The present invention has the following beneficial effects:

[0015] (1) Based on supercritical water gasification technology, this invention achieves high-yield hydrogen production through methane steam reforming and water-gas shift reaction, and complete carbon capture of carbon dioxide, thus realizing efficient and low-carbon hydrogen production from coal.

[0016] (2) The present invention rationally divides the gasification syngas of the system, effectively preheats the gasification feedwater and reforming feedwater, reduces the heat exchange temperature difference between the hot and cold ends of the heat exchangers, and achieves efficient matching of the system waste heat.

[0017] (3) By adjusting the feedwater flow rate of the reforming reaction, the present invention promotes the methane steam reforming and water-gas shift reaction, thereby increasing the hydrogen production capacity and improving the hydrogen production efficiency of the system. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the coal-to-hydrogen carbon capture system based on methane steam reforming in this invention.

[0019] Figure 2 This is a graph showing the effect of methane reforming temperature on the yield of gas components.

[0020] Figure 3 The graph shows the effect of coal-water slurry concentration on the system efficiency.

[0021] Figure 1 In the middle section: 1 is the gasification feed water pump, 2 is the low-temperature preheater, 3 is the medium-temperature preheater, 4 is the high-temperature preheater, 5 is the gasification reactor, 6 is the throttle valve, 7 is the No. 1 gas-liquid separator, 8 is the regenerator, 9 is the reforming reactor, 10 is the shift reactor, 11 is the reforming feed water pump, 12 is the No. 1 heater, 13 is the No. 2 heater, 14 is the cooler, 15 is the No. 2 gas-liquid separator, and 16 is the pressure swing adsorption device. Detailed Implementation

[0022] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0023] like Figure 1As shown, the coal-to-hydrogen carbon capture system based on methane steam reforming according to the present invention includes a gasification feedwater pump 1, a low-temperature preheater 2, a medium-temperature preheater 3, a high-temperature preheater 4, a gasification reactor 5, a throttle valve 6, a first gas-liquid separator 7, a regenerator 8, a reforming reactor 9, a shift reactor 10, a reforming feedwater pump 11, a first heater 12, a second heater 13, a cooler 14, a second gas-liquid separator 15, and a pressure swing adsorption device 16. Gasification feedwater, after passing through gasification feedwater pump 1, is connected to the cold ends of low-temperature preheater 2, medium-temperature preheater 3, and high-temperature preheater 4 in sequence. The cold end outlet of high-temperature preheater 4 is connected to the inlet of gasification reactor 5. Coal and oxygen are connected to the inlet of gasification reactor 5 via pipelines. Ash is discharged from the outlet of gasification reactor 5 through an ash discharge pipeline. Syngas from the outlet of gasification reactor 5 is connected to the hot ends of high-temperature preheater 4, medium-temperature preheater 3, and low-temperature preheater 2 in sequence. The working fluid portion of the hot end outlet of high-temperature preheater 4 is diverted to the hot end inlet of heater 13. The hot end outlet of heater 13 and the hot end outlet of medium-temperature preheater 3 are both connected to the hot end inlet of low-temperature preheater 2. The hot end outlet of low-temperature preheater 2 is connected to the inlet of throttle valve 6, and the outlet of throttle valve 6 is connected to the inlet of gas-liquid separator 7. The liquid phase outlet of gas-liquid separator 7 is water, and the working fluid at the gas phase outlet is connected to the cold end inlet of regenerator 8. Reforming feedwater is then... After passing through the reforming feedwater pump 11, the feedwater is connected to the cold ends of heater 12 and heater 13, respectively. The cold end outlet of heater 13 is connected to the cold end inlet of regenerator 8. The gas phase outlet of gas-liquid separator 7 and the cold end outlet of heater 13 are connected to the inlet of reforming reactor 9 after passing through regenerator 8. Oxygen is connected to the inlet of reforming reactor 9 via a pipeline. The outlet of reforming reactor 9 is connected to the hot end inlet of regenerator 8, and the hot end outlet of regenerator 8 is connected to the inlet of shift reactor 10. The working fluid at the outlet of shift reactor 10 is connected to the hot end inlet of heater 12. The hot end outlet of heater 12 is connected to the inlet of gas-liquid separator 15 after passing through cooler 14. The liquid phase outlet of gas-liquid separator 15 is water, and the gas phase outlet working fluid is connected to the inlet of pressure swing adsorption device 16. High-purity hydrogen is obtained at the outlet of pressure swing adsorption device 16, and the remaining carbon dioxide is completely captured.

[0024] Preferably, the gasification reactor 5 operates at a temperature of 500℃-700℃, an operating pressure of 23MPa-26MPa, and a coal-water slurry concentration of 20%-35%. This allows for supercritical coal-water gasification under these conditions, which is beneficial for the system to achieve a higher hydrogen production yield.

[0025] Preferably, the reforming reactor 9 operates at a temperature of 900℃-1200℃. This promotes the methane steam reforming reaction, increases the system's hydrogen production capacity, and improves the system's hydrogen production efficiency.

[0026] Preferably, the operating temperature of the shift reactor 10 is 180℃-240℃, which is conducive to the occurrence of water-gas shift reaction under these conditions.

[0027] Preferably, the heat required by the system is provided through a partial oxidation process of the fuel, achieving self-heating balance of the system. The oxygen entering the system is split into two streams. One stream of oxygen enters the gasification reactor 5, where it undergoes a partial oxidation supercritical water gasification reaction with coal and water, so that the heat released is exactly what is needed for the gasification reaction. The other stream of oxygen enters the reforming reactor 9, where it undergoes a partial oxidation methane reforming reaction with syngas and water, so that the heat released is exactly what is needed for the reforming reaction.

[0028] Preferably, by rationally diverting the syngas at the hot end outlet of the high-temperature preheater 4, the gasification feedwater and reforming feedwater are effectively preheated. The minimum heat exchange temperature difference between the low-temperature preheater 2, the medium-temperature preheater 3, the high-temperature preheater 4 and the second heater 13 is 5℃-20℃, which reduces the heat exchange temperature difference between the hot and cold ends during the heat exchange process and reduces irreversible heat transfer losses.

[0029] Preferably, the inlet temperature of the pressure swing adsorption device 16 is 20℃-40℃ and the inlet pressure is 0.8MPa-3MPa, so as to meet the operating conditions of pressure swing adsorption hydrogen production.

[0030] like Figure 1As shown, the operation method of the coal-to-hydrogen carbon capture system based on methane steam reforming according to the present invention is as follows: Gasification feedwater, after being pressurized by gasification feedwater pump 1, is preheated by passing through the cold ends of low-temperature preheater 2, medium-temperature preheater 3, and high-temperature preheater 4, and then enters the gasification reactor 5; coal and oxygen enter the gasification reactor 5, where a partially oxidized supercritical water gasification reaction occurs; ash is discharged from the outlet of the gasification reactor 5, and syngas passes through the high-temperature preheater 4, medium-temperature preheater 3, and low-temperature preheater 4, respectively, from the outlet of the gasification reactor 5. The hot end of the high-temperature preheater 2 preheats the gasification feedwater; the syngas from the hot end outlet of the high-temperature preheater 4 is partially diverted to the hot end inlet of the second heater 13 to preheat the reforming feedwater; the syngas, after waste heat recovery, flows from the hot end outlet of the low-temperature preheater 2 through the throttle valve 6 to reduce its pressure, and then enters the first gas-liquid separator 7 for gas-liquid separation; by adjusting the feedwater flow rate into the reforming feedwater pump 11, the methane steam reforming reaction in the reforming reactor 9 and the water-gas shift reaction in the shift reactor 10 can be promoted. This increases the system's hydrogen production efficiency. After being pressurized by reforming feedwater pump 11, the reforming feedwater is preheated sequentially through the cold ends of heater 12 and heater 13. Oxygen enters the reforming reactor 9. The syngas from the gas phase outlet of gas-liquid separator 7 and the reforming feedwater from the cold end outlet of heater 13 enter the regenerator 8 for heating, and then enter the reforming reactor 9 to undergo a partially oxidized methane reforming reaction. The reformed gas from the outlet of reforming reactor 9 passes through the hot end of regenerator 8 and enters the shift reactor 1. A water-gas shift reaction occurs in reactor 10; the working fluid at the outlet of reactor 10 passes through the hot end of heater 12 and cooler 14, and then enters gas-liquid separator 15 for gas-liquid separation; the water at the liquid outlet of gas-liquid separator 15 is discharged through a pipeline, and the working fluid at the gas outlet includes hydrogen and carbon dioxide; the working fluid at the gas outlet of gas-liquid separator 15 enters pressure swing adsorption device 16 for hydrogen separation and purification, and high-purity hydrogen product is obtained at the outlet of pressure swing adsorption device 16, while the remaining carbon dioxide is completely captured.

[0031] like Figure 2 As shown, when the methane reforming temperature increases from 700℃ to 1200℃, compared with the composition of the syngas gasified at the outlet of the gasification reactor 5, the increase in reforming temperature is beneficial to promoting the methane steam reforming reaction, converting more methane in the syngas into hydrogen, and thus increasing the system's hydrogen production. When the reforming temperature is above 900℃, the system's hydrogen production gradually approaches its maximum value and tends to stabilize.

[0032] like Figure 3 As shown, when the concentration of the coal-water slurry increases from 10% to 40%, the hydrogen production efficiency of the system first increases and then decreases. When the concentration of the coal-water slurry is 25%, the hydrogen production efficiency of the system reaches its maximum value, and its energy efficiency and... The efficiencies were 75.2% and 65.1%, respectively.

[0033] This invention, based on supercritical water gasification technology, achieves high-yield hydrogen production through methane steam reforming and water-gas shift reaction, while realizing complete carbon capture of carbon dioxide. The system's gasification syngas is rationally diverted to effectively preheat the gasification feedwater and reforming feedwater, reducing the heat exchange temperature difference between the hot and cold ends of the heat exchangers and achieving efficient matching of system waste heat. By adjusting the feedwater flow rate for the reforming reaction, the methane steam reforming and water-gas shift reaction are promoted, increasing the system's hydrogen production capacity and improving its efficiency, ultimately achieving efficient, clean, and low-carbon hydrogen production from coal.

Claims

1. A coal-to-hydrogen carbon capture system based on methane steam reforming, characterized in that: The system includes a gasification feedwater pump (1), a low-temperature preheater (2), a medium-temperature preheater (3), a high-temperature preheater (4), a gasification reactor (5), a throttle valve (6), a first gas-liquid separator (7), a regenerator (8), a reforming reactor (9), a shift reactor (10), a reforming feedwater pump (11), a first heater (12), a second heater (13), a cooler (14), a second gas-liquid separator (15), and a pressure swing adsorption device (16). The gasification feedwater, after passing through the gasification feedwater pump (1), is sequentially connected to the cold ends of the low-temperature preheater (2), the medium-temperature preheater (3), and the high-temperature preheater (4). The cold end outlet of the preheater (4) is connected to the inlet of the gasification reactor (5); coal and oxygen are connected to the inlet of the gasification reactor (5) via pipelines; ash is discharged from the outlet of the gasification reactor (5) via an ash discharge pipeline; the syngas from the outlet of the gasification reactor (5) is sequentially connected to the hot end of the high-temperature preheater (4), the medium-temperature preheater (3), and the low-temperature preheater (2); the working fluid portion of the hot end outlet of the high-temperature preheater (4) is diverted to the hot end inlet of the second heater (13); the hot end outlet of the second heater (13) and the hot end outlet of the medium-temperature preheater (3) are both connected to the hot end inlet of the low-temperature preheater (2); the low-temperature preheater (2) The hot end outlet is connected to the inlet of the No. 1 gas-liquid separator (7) via a throttle valve (6); the liquid phase outlet of the No. 1 gas-liquid separator (7) is water, and the working fluid at the gas phase outlet is connected to the cold end inlet of the regenerator (8); the reforming feedwater, after passing through the reforming feedwater pump (11), is connected in sequence to the cold ends of the No. 1 heater (12) and the No. 2 heater (13), and the cold end outlet of the No. 2 heater (13) is connected to the cold end inlet of the regenerator (8); the gas phase outlet of the No. 1 gas-liquid separator (7) and the cold end outlet of the No. 2 heater (13), after passing through the regenerator (8), are respectively connected to the inlet of the reforming reactor (9); oxygen is connected to the reforming reactor via a pipeline. The reactor (9) inlet is connected to the reformer (9) outlet, which is connected to the hot end inlet of the regenerator (8). The hot end outlet of the regenerator (8) is connected to the inlet of the shift reactor (10). The working medium at the outlet of the shift reactor (10) is connected to the hot end inlet of the first heater (12). The hot end outlet of the first heater (12) is connected to the inlet of the second gas-liquid separator (15) after passing through the cooler (14). The liquid phase outlet of the second gas-liquid separator (15) is water, and the working medium at the gas phase outlet is connected to the inlet of the pressure swing adsorption device (16). The pressure swing adsorption device (16) outlet produces high-purity hydrogen product, and the remaining carbon dioxide is completely captured.

2. The coal-to-hydrogen carbon capture system based on methane steam reforming according to claim 1, characterized in that: The gasification reactor (5) operates at a temperature of 500℃-800℃, a pressure of 23MPa-30MPa, and a coal-water slurry concentration of 10%-40%.

3. The coal-to-hydrogen carbon capture system based on methane steam reforming according to claim 1, characterized in that: The operating temperature of the reforming reactor (9) is 700℃-1200℃.

4. The coal-to-hydrogen carbon capture system based on methane steam reforming according to claim 1, characterized in that: The operating temperature of the shift reactor (10) is 180℃-240℃.

5. The coal-to-hydrogen carbon capture system based on methane steam reforming according to claim 1, characterized in that: The heat required by the system is provided by the partial oxidation of fuel to achieve self-heating balance. The oxygen entering the system is split into two streams. One stream of oxygen enters the gasification reactor (5) and undergoes a partial oxidation supercritical water gasification reaction with coal and water, so that the released heat is just enough to provide the heat required for the gasification reaction. The other stream of oxygen enters the reforming reactor (9) and undergoes a partial oxidation methane reforming reaction with syngas and water, so that the released heat is just enough to provide the heat required for the reforming reaction.

6. The coal-to-hydrogen carbon capture system based on methane steam reforming according to claim 1, characterized in that: By diverting the syngas from the hot end outlet of the high-temperature preheater (4), the gasification feedwater and reforming feedwater are effectively preheated. The minimum heat exchange temperature difference between the low-temperature preheater (2), the medium-temperature preheater (3), the high-temperature preheater (4) and the second heater (13) is 5℃-20℃.

7. The coal-to-hydrogen carbon capture system based on methane steam reforming according to claim 1, characterized in that: The inlet temperature of the pressure swing adsorption device (16) is 20℃-40℃, and the inlet pressure is 0.8MPa-3MPa.

8. The operation method of the coal-to-hydrogen carbon capture system based on methane steam reforming as described in any one of claims 1 to 7, characterized in that: After being pressurized by the gasification feedwater pump (1), the gasification feedwater is preheated sequentially through the cold ends of the low-temperature preheater (2), the medium-temperature preheater (3), and the high-temperature preheater (4) before entering the gasification reactor (5). Coal and oxygen enter the gasification reactor (5) and undergo a partially oxidized supercritical water gasification reaction. Ash is discharged from the outlet of the gasification reactor (5), and syngas is preheated from the outlet of the gasification reactor (5) by sequentially passing through the hot ends of the high-temperature preheater (4), the medium-temperature preheater (3), and the low-temperature preheater (2). (4) The syngas from the hot end outlet is partially diverted to the hot end inlet of the second heater (13) to preheat the reforming feedwater; after waste heat recovery, the syngas flows from the hot end outlet of the low-temperature preheater (2) through the throttle valve (6) to reduce the pressure, and then enters the first gas-liquid separator (7) for gas-liquid separation; by adjusting the feedwater flow rate into the reforming feedwater pump (11), the methane steam reforming reaction in the reforming reactor (9) and the water-gas shift reaction in the shift reactor (10) are promoted, thereby increasing the hydrogen production efficiency of the system; the reforming feedwater passes through After being pressurized by the reforming feedwater pump (11), the feedwater is preheated by passing through the cold ends of the No. 1 heater (12) and the No. 2 heater (13) in sequence. Oxygen enters the reforming reactor (9). The synthesis gas from the gas phase outlet of the No. 1 gas-liquid separator (7) and the reforming feedwater from the cold end outlet of the No. 2 heater (13) enter the regenerator (8) for heating, and then enter the reforming reactor (9) to undergo a partially oxidized methane reforming reaction. The reformed gas from the outlet of the reforming reactor (9) passes through the hot end of the regenerator (8) and enters the shift reactor (10) to generate water vapor. Shift reaction; the working fluid at the outlet of the shift reactor (10) passes through the hot end of the first heater (12) and the cooler (14) and then enters the second gas-liquid separator (15) for gas-liquid separation; the water at the liquid phase outlet of the second gas-liquid separator (15) is discharged through a pipeline, and the working fluid at the gas phase outlet includes hydrogen and carbon dioxide; the working fluid at the gas phase outlet of the second gas-liquid separator (15) enters the pressure swing adsorption device (16) for hydrogen separation and purification, and the outlet of the pressure swing adsorption device (16) yields a high-purity hydrogen product, while the remaining carbon dioxide is completely captured.

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