A methanol water reforming hydrogen production system and control method

Abstract

The present application provides a methanol-water reforming hydrogen production system and a control method. The system includes a mixer, a heat exchanger for preheating methanol-water, an integrated reformer and burner, a palladium membrane separator for purifying hydrogen, a first heater for heating the palladium membrane separator, a second heater for heating the palladium membrane separator inlet gas, and a methanation device for removing CO impurities. The burner is provided with a first burner inlet for supplying methanol and a second burner inlet for supplying hydrogen-containing tail gas from the palladium membrane separator, which is used to heat the reformer, and its combustion tail gas preheats the methanol-water through the heat exchanger. The control method controls the burner to preheat the reformer and the heat exchanger, and control them within their respective operating temperature ranges; controls the first heater and the second heater to heat the palladium membrane separator and the gas, and control them at the optimal operating temperature. The present application accurately and efficiently controls each process step at the optimal operating temperature through the reasonable setting of the system.

Description

Technical Field

[0001] The present application relates to the technical field of methanol-water reforming hydrogen production, and in particular to a methanol-water reforming hydrogen production system and a control method. Background Art

[0002] With the increasing fossil energy crisis and environmental pollution, there is an urgent need to develop and utilize clean, pollution-free and efficient energy. Hydrogen has a wide range of sources, high combustion calorific value, and produces water as a reaction product. It has the advantages of high efficiency, cleanliness and sustainable development, and is recognized as one of the most promising energy carriers in the future.

[0003] At present, the traditional methods of hydrogen production include water electrolysis and fossil fuel production such as coal, natural gas and methanol. Among them, water electrolysis consumes a lot of electricity and has a high cost. The fossil fuel hydrogen production process is relatively mature and has a low price. Among them, methanol reforming hydrogen production has a wide range of raw materials and low prices. Methanol has a high hydrogen content and a high hydrogen production yield. At the same time, the hydrogen production device can be made into a skid-mounted or mobile methanol water reforming hydrogen production module, which is particularly suitable for hydrogen fuel cells.

[0004] There are three ways to produce hydrogen from methanol. Compared with methanol cracking and methanol partial oxidation, methanol-water reforming has the advantages of high hydrogen production ratio, low reaction temperature and wide application. The traditional methanol reforming reaction temperature is between 200℃ and 300℃, and it is often connected to pressure swing adsorption to purify hydrogen. However, pressure swing adsorption has the disadvantages of large footprint, high investment and low recovery rate, and is not suitable for fuel cells and applications with limited volume.

[0005] Palladium membrane purification uses the mechanism of palladium's selective permeability to hydrogen. Theoretically, it can isolate any gas except hydrogen. It has high hydrogen purity, small footprint, high integration, and high purification efficiency, which is conducive to the purification of high-purity hydrogen. The operating temperature of palladium membrane is 350℃~430℃, and the temperature requirement is relatively high.

[0006] Traditional methanol reforming hydrogen production often uses intermediate heat transfer media such as heat transfer oil to provide heat for the reaction, but heat transfer oil is prone to cracking and deterioration after long-term use, which poses a safety hazard; the heat transfer oil system needs to be equipped with high-temperature oil pumps, expansion tanks, heat transfer oil furnaces and other equipment. The system is complex and occupies a large volume, which is not conducive to integration. In addition, the temperature of the heat transfer oil itself is lower than 350°C, and the temperature of the hydrogen-rich gas produced by the reformer is lower than 300°C, which does not reach the working temperature of the palladium membrane and needs to be heated before entering the palladium membrane for purification.

[0007] The invention patent application with publication number CN111825057A provides a temperature control system and a temperature control method for a palladium tube purifier in a methanol-water hydrogen generator, which uses high-temperature flue gas to heat the palladium membrane. The invention patent application with publication number CN112209341A provides a methanol reforming hydrogen production system and process, which is equipped with an independent burner and reformer, and heat is supplied to the reformer through an intermediate heat exchange medium.

[0008] However, the above technical solution still has the following shortcomings:

[0009] 1. A separate burner and buffer chamber or heat exchanger is required, the system structure is complex, the heat exchange effect is unstable, the heat exchange efficiency is low, and the thermal response is delayed;

[0010] 2. The palladium membrane purification device lacks a heating device during startup, so the device cannot immediately reach the optimal working temperature after startup; at the same time, the independently set heater also has problems such as low heat exchange efficiency and delayed thermal response, which increases the difficulty of system control;

[0011] 3. The burner and / or reformer and palladium membrane separator lack pressure control, and the system cannot be accurately controlled in the optimal working state. Summary of the invention

[0012] In view of the above-mentioned defects in the prior art, the present application provides a methanol-water reforming hydrogen production system and a control method with high efficiency heat exchange and accurate control of the temperature of each node in the process flow.

[0013] The methanol-water reforming hydrogen production system provided in the present application includes a reformer, a burner and a heat exchanger. The burner is a high-pressure catalytic combustion reactor, including a first burner inlet and a combustion exhaust gas outlet; the reformer includes a first methanol-water inlet and a hydrogen-rich mixed gas outlet; the heat exchanger includes a second methanol-water inlet, a methanol-water outlet, a combustion exhaust gas inlet, and an exhaust port; the methanol-water outlet is connected to the first methanol-water inlet, and the combustion exhaust gas outlet is connected to the combustion exhaust gas inlet; the reformer and the burner are integrated into one.

[0014] The use of a high-pressure catalytic combustion reactor is not only convenient for integration with the reformer, but also can utilize methanol without the need for additional fuel, making the system easy to integrate and modularize. The integrated burner and reformer can achieve efficient heat exchange and rapid response, making it easy for the system to accurately control the reaction temperature. The combustion tail gas is preheated and gasified by the heat exchanger to the methanol water, further ensuring that the reformer is at the optimal operating temperature.

[0015] Preferably, the reformer is a sleeve-type reformer, comprising an outer cylinder and an inner cylinder that are matched with each other, the cross-sections of the outer cylinder and the inner cylinder are polygonal, circular or oval, and a reforming catalyst is arranged between the outer cylinder and the inner cylinder; the inner cylinder also constitutes the outer shell of the burner, and a combustion catalyst is arranged inside the outer shell.

[0016] The sleeve-type reformer and burner can withstand high pressure. Dome-shaped ends can be set at both ends of the sleeve to form a high-pressure tank-shaped container to withstand the working pressure of high-pressure catalytic combustion and high-pressure reforming. At the same time, setting the burner inside is conducive to efficient heat exchange.

[0017] Preferably, the reformer is a plate-type reformer with a reforming catalyst disposed inside; the burner is a plate-type burner with a combustion catalyst disposed inside; the plate-type reformer and the plate-type burner are alternately stacked, the plate-type reformers are arranged in parallel or in series, and the plate-type burners are arranged in parallel or in series.

[0018] Plate reformer and plate burner are modular subsystems that are easy to integrate into the upper system. At the same time, the number of modules can be flexibly increased or decreased according to system needs.

[0019] Preferably, the methanol-water reforming hydrogen production system also includes a mixer with a stirring function, which is used to stir and mix methanol and water; it also includes a desalted water storage tank and a water pump, which are used to provide desalted water with a maximum pressure of more than 3.0 MPa to the mixer; it also includes a methanol storage tank and a methanol pump, which are used to provide methanol with a maximum pressure of more than 3.0 MPa to the mixer and the first burner inlet; it also includes an air source and an air pump, which are used to provide air with a maximum pressure of more than 3.0 MPa to the first burner inlet; the rated pressures of the mixer, the heat exchanger, and the reformer are not less than 3.0 MPa.

[0020] The desalted water used for methanol water reforming is required to contain no or less impurities such as sulfur, chlorine and heavy metal ions, and is mixed with methanol in a mixer in a certain proportion. At the same time, the water pump, methanol pump and air pump provide the medium with suitable pressure for the high-pressure reformer and high-pressure catalytic burner.

[0021] Preferably, the water pump is a centrifugal pump, a turbine pump or a piston pump; the methanol pump is a metering pump; the air pump is a centrifugal pump, a turbine pump or a piston pump; and the heat exchanger is a sleeve-and-tube type, a shell-and-tube type or a microchannel type heat exchanger.

[0022] Preferably, the reforming catalyst is a high-temperature reforming catalyst with an operating temperature range of 300°C to 600°C; the maximum operating temperature of the combustion catalyst is not less than 600°C, and the maximum operating temperature of the heat exchanger is not less than 600°C.

[0023] The rated pressure of the reformer is the maximum allowable pressure, and the actual working pressure is not higher than the rated pressure. The rated pressure of the reformer used for high-pressure reforming reaction is 3.0MPa or higher. The use of high-temperature reforming catalyst can improve the methanol conversion rate on the one hand, and on the other hand, make the temperature of the hydrogen-rich mixed gas of the conversion product higher, so that it matches the subsequent palladium membrane purification process. The working temperature of the high-pressure combustion catalyst is higher than the working temperature setting of the reforming catalyst. For example, Pt / Al2O3 can be used to make the temperature of the hot side of the burner and the heat exchanger higher than the working temperature of the reformer to ensure the temperature gradient and heat transfer efficiency.

[0024] Preferably, a first flow control valve is provided between the methanol storage tank and the first burner inlet, a second flow control valve is provided between the methanol storage tank and the mixer, and a first pressure control valve is provided at the exhaust port. The first pressure control valve is used to control the pressure of the combustion exhaust gas and the high-pressure catalytic combustion reaction to keep them in the best working state.

[0025] Preferably, the first flow control valve and the second flow control valve are needle valves; the first pressure control valve is a back pressure valve, or a solenoid valve matched with a pressure sensor. The back pressure valve can control the pressure and also act as a safety valve. A combination of a pressure sensor and a solenoid valve can also be used for pressure control to achieve more accurate and flexible control.

[0026] Preferably, the methanol water reforming hydrogen production system further includes a palladium membrane separator, which includes a hydrogen-rich mixed gas inlet, a purified hydrogen outlet, and a separator tail gas outlet; the burner further includes a second burner inlet; the hydrogen-rich mixed gas inlet is connected to the hydrogen-rich mixed gas outlet, and the separator tail gas outlet is connected to the second burner inlet. The tail gas of the palladium membrane separator contains combustible gas, which can be recycled to improve system efficiency.

[0027] Preferably, the methanol water reforming hydrogen production system further comprises a first heater, which is integrated with the palladium membrane separator and used to heat the palladium membrane separator; the first heater is a radiation heater or a patch heater. The first heater is integrated into the palladium membrane separator to preheat the palladium membrane separator when the system is started and to keep it near the optimal operating temperature when the system is running.

[0028] Preferably, the palladium membrane separator comprises one palladium tube, or multiple palladium tubes connected in parallel or in series; the operating temperature range of the palladium membrane separator is 400±20° C. By controlling the burner and other components, the temperature of the hydrogen-rich mixed gas output by the reformer can be controlled within the operating temperature range of the palladium membrane separator, making the system simple and efficient.

[0029] Preferably, the methanol water reforming hydrogen production system further includes a second heater, which is disposed between the hydrogen-rich mixed gas outlet and the hydrogen-rich mixed gas inlet; the second heater is a radiation heater, a patch heater, or a pipeline built-in heater. The second heater is used to fine-tune the temperature of the hydrogen-rich mixed gas to reduce the difficulty of burner control and make the temperature control of the hydrogen-rich mixed gas more accurate.

[0030] Preferably, a third flow control valve is provided between the separator tail gas outlet and the second burner inlet, and the purified hydrogen outlet is connected to a second pressure control valve. The second pressure control valve is used to control the working pressure of the reformer and the palladium membrane separator, and can make the output hydrogen meet the hydrogen pressure requirements of the hydrogen-using system such as a fuel cell.

[0031] Preferably, the methanol water reforming hydrogen production system further includes a methanation device, which is arranged between the purified hydrogen outlet and the second pressure control valve, and the operating temperature range of the methanation device is 300°C to 500°C. The methanation device is used to remove CO impurities in the purified hydrogen to below 0.2ppm, so that the hydrogen purity is greater than 99.9999%, so as to meet the requirements of hydrogen systems such as fuel cells. The purified hydrogen output by the palladium membrane separator has a temperature of about 400°C and can be directly input into the methanation device for treatment.

[0032] The methanol-water reforming hydrogen production system control method provided in the present application is used to control the above-mentioned methanol-water reforming hydrogen production system, comprising the steps of:

[0033] S10. Close the second methanol water inlet, supply methanol as fuel to the first burner inlet, and preheat the heat exchanger and the reformer to not less than the lower limit of their respective operating temperature ranges;

[0034] S20. Open the second methanol-water inlet, and maintain the mixer within its operating temperature range by controlling the burner, and control the temperature of the methanol-water mixed gas at the methanol-water outlet within a range of 400°C to 420°C; maintain the reformer within its operating temperature range by controlling the burner, and control the temperature of the hydrogen-rich mixed gas within a range of 400°C to 420°C.

[0035] Preferably, the control method further includes step S11 between step S10 and step S20, and step S21 after step S20:

[0036] S11. Before step S10 ends, the first heater is turned on to heat the palladium membrane separator to a temperature not lower than the lower limit of its operating temperature range;

[0037] S21. Maintain the palladium membrane separator within its operating temperature range by controlling the first heater, and control the temperature of the gas entering the hydrogen-rich mixed gas inlet within the operating temperature range of the palladium membrane separator by controlling the second heater.

[0038] Due to the reasonable setting of the working temperature of the burner, reformer and palladium membrane separator, the difficulty of system control is reduced. The system only needs to fine-tune the working state of the burner by controlling the burner and the first flow control valve, the second flow control valve and the third flow control valve to control the reformer at the optimal working temperature. At the same time, after the preheating is completed, the system only needs to fine-tune the temperature of the hydrogen-rich mixed gas and the palladium membrane heater by controlling the first heater and the second heater to control the palladium membrane separator at the optimal working temperature, and at the same time make the temperature of the purified hydrogen output close to the optimal working temperature of the methanation device. When the first pressure control valve and the second pressure control valve are electromagnetic valves matched with pressure sensors, the working pressure of the burner and the working pressure of the reformer, palladium membrane separator and methanation device can also be adjusted to further optimize the working state of the subsystem.

[0039] The technical effects of this application are:

[0040] 1. This application optimizes the preheating of methanol water, the preheating of the reformer and the palladium membrane separator, the operating temperature setting of the burner, the operating temperature setting of the reformer, etc., so that the temperatures of the working media upstream and downstream of the process flow match each other, simplifying the system setting and improving the system efficiency;

[0041] 2. The integrated reformer and burner, the integrated first heater and palladium membrane separator, the high-pressure catalytic combustion reactor using methanol and separator tail gas make the system easy to control accurately, and at the same time, the structure is compact, easy to modularize, and easy to further integrate into the hydrogen system;

[0042] 3. Combined with the above-mentioned optimized system settings, the system control method provided in this application enables each subsystem to be in the best working state during the system startup and normal operation, further improving the system efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The present application is further described in detail below with reference to the accompanying drawings and specific implementation methods:

[0044] Figure 1 This is a process flow chart of a methanol-water reforming hydrogen production system according to Embodiment 1;

[0045] Figure 2 is a schematic front view of a reformer and a burner of Embodiment 2;

[0046] Figure 3 is a schematic top view of a reformer and a burner of Embodiment 2;

[0047] Figure 4 is a process flow chart of a methanol-water reforming hydrogen production system according to Embodiment 2;

[0048] Figure 5 is a schematic top view of a reformer and a burner of Embodiment 2;

[0049] Figure 6 is a schematic front view of a reformer and a burner of Embodiment 2;

[0050] Figure 7 is a process flow chart of a methanol-water reforming hydrogen production system according to Embodiment 3 and Embodiment 4;

[0051] Description of Figure Numbers:

[0052] 1. Desalted water storage tank, 2. Water pump, 3. Mixer, 4. First pressure control valve, 5. Heat exchanger, 6. Reformer, 7. Burner, 8. First flow control valve, 9. Second flow control valve, 10. Methanol pump, 11. Air pump, 12. Methanol storage tank, 13. Air source, 14. Hydrogen system interface, 15. Third flow control valve, 16. First heater, 17. Palladium membrane separator, 18. Second pressure control valve, 19. Second heater, 20. Methane makeup device , 501. second methanol water inlet, 502. methanol water outlet, 503. combustion tail gas inlet, 504. exhaust port, 601. first methanol water inlet, 602. hydrogen-rich mixed gas outlet, 603. reforming catalyst, 701. first burner inlet, 702. combustion tail gas outlet, 703. second burner inlet, 704. combustion catalyst, 1701. hydrogen-rich mixed gas inlet, 1702. purified hydrogen outlet, 1703. separator tail gas outlet. DETAILED DESCRIPTION

[0053] In order to more clearly illustrate the technical solutions in the present application or the prior art, the specific implementation methods of the present application will be described below with reference to the accompanying drawings. In order to make the drawings concise, only the parts related to the present application are schematically shown in each figure, and they do not represent the actual components of the product, method or process flow. In addition, in order to make the drawings concise and easy to understand, in some figures, only one of the components or modules with the same structure or function is schematically drawn, or only one of them is marked. In this article, "one" not only means "only one", but also can mean "more than one".

[0054] It should be further understood that the term "and / or" used in the specification of this application and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes these combinations. In this article, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, and it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0055] Embodiment 1: A methanol-water reforming hydrogen production system.

[0056] like Figure 1 As shown, the methanol water reforming hydrogen production system of this embodiment includes a reformer 6, a burner 7 and a heat exchanger 5. The burner 7 is a high-pressure catalytic combustion reactor, including a first burner inlet 701, a second burner inlet 703 and a combustion tail gas outlet 702; the reformer 6 includes a first methanol water inlet 601 and a hydrogen-rich mixed gas outlet 602; the heat exchanger 5 includes a second methanol water inlet 501, a methanol water outlet 502, a combustion tail gas inlet 503, and an exhaust port 504; the methanol water outlet 502 is connected to the first methanol water inlet 601, and the combustion tail gas outlet 702 is connected to the combustion tail gas inlet 503. Figure 2 and 3 As shown, the reformer 6 and the burner 7 are integrated into one. The reformer 6 is a sleeve-type reformer, including an outer cylinder and an inner cylinder that are matched, the cross-sections of the outer cylinder and the inner cylinder are concentrically arranged circles, and a reforming catalyst 603 is filled between the outer cylinder and the inner cylinder. The outer cylinder and the inner cylinder can also be matched polygonal or oval. The inner cylinder also constitutes the outer shell of the burner 7, and a combustion catalyst 704 is filled therein.

[0057] The heat exchanger 5, the reformer 6, and the burner 7 are located in the core process flow of this embodiment. The burner 7 uses methanol for high-pressure catalytic reaction without the need for additional fuel; and the burner 7 is integrated inside the reformer 6 to supply heat for the reforming reaction through heat conduction and heat radiation. While heating the reformer 6, its combustion exhaust gas is preheated for methanol water through the heat exchanger 5, making the system highly efficient and compact in structure.

[0058] This embodiment further includes a mixer 3 with a stirring function, which is used to stir and mix methanol and water; and also includes a desalted water storage tank 1 and a water pump 2. The water pump 2 is a centrifugal pump, and a turbine pump or a piston pump can also be used to increase the pressure of the desalted water from 0.1MPa to 3.0MPa and input it into the mixer 3 to mix with methanol, so as to meet the requirement that methanol water undergoes a high-pressure reaction in the reformer 6 to prepare a high-pressure hydrogen-rich mixed gas.

[0059] The present embodiment further includes a methanol storage tank 12 and a methanol pump 10. The methanol pump 10 is a metering pump for increasing the pressure of methanol from 0.1 MPa to 3.0 MPa and inputting it into the mixer 3 to mix with desalted water, so as to meet the requirement of preparing high-pressure hydrogen-rich mixed gas by high-pressure reaction of methanol water in the reformer 6. The present embodiment further includes an air source 13 and an air pump 11. The air pump 11 is a centrifugal pump, and a turbine pump or a piston pump can also be selected to provide air with a pressure of 3.0 MPa to the first burner inlet 701. Accordingly, the rated pressure of the mixer 3 and the heat exchanger 5 is 3.0 MPa. The heat exchanger 5 is a shell-and-tube heat exchanger, and a shell-and-tube or microchannel heat exchanger can also be selected.

[0060] The rated pressure of the reformer 6 is 5 MPa, the reforming catalyst 603 is a high-temperature reforming catalyst with an operating temperature range of 300°C to 600°C; the maximum operating temperature of the combustion catalyst 704 is not less than 600°C, and the maximum operating temperature of the heat exchanger 5 is not less than 600°C.

[0061] Methanol and water are mixed in proportion in the mixer 3 and flow through the heat exchanger 5 to exchange heat with the high-temperature exhaust gas of nearly 600°C from the burner 7, and are gasified into high-pressure gas, the temperature of which reaches the optimal operating temperature of the reforming catalyst 603, that is, close to the center temperature of its operating temperature range.

[0062] A first flow control valve 8 is provided between the methanol storage tank 12 and the first burner inlet 701, and a second flow control valve 9 is provided between the methanol storage tank 12 and the mixer 3; a first pressure control valve 4 is provided at the exhaust port 504. The first flow control valve 8 and the second flow control valve 9 are needle valves; and the first pressure control valve 4 is a back pressure valve.

[0063] The first flow control valve 8 and the second flow control valve 9 are used to control the methanol flow to the burner 7 and the mixer 3 during startup and operation. For example, when starting preheating, the second flow control valve 9 is closed, and the first flow control valve 8 is opened to a larger opening so that the system can be preheated quickly. During normal operation, the first flow control valve 8 only needs to be maintained at a smaller opening, and the second flow valve 9 is opened to a larger opening to provide the system with methanol for reforming. The first pressure control valve 4 is used to control the exhaust gas pressure of the burner 7, and is also used as a safety valve to ensure the normal progress of the high-pressure catalytic combustion reaction. It can also be replaced by a solenoid valve with a matching pressure sensor to achieve more precise control.

[0064] like Figure 1As shown, this embodiment also includes a palladium membrane separator 17, and the palladium membrane separator 17 is provided with a hydrogen-rich mixed gas inlet 1701, a purified hydrogen outlet 1702 and a separator tail gas outlet 1703; the hydrogen-rich mixed gas inlet 1701 is connected to the hydrogen-rich mixed gas outlet 602, and the separator tail gas outlet 1703 is connected to the second burner inlet 703. A third flow control valve 15 is provided between the separator tail gas outlet 1703 and the second burner inlet 703, and the purified hydrogen outlet 1702 is connected to the second pressure control valve 18. The second pressure control valve 18 is connected to the hydrogen system interface 14 to provide high-purity hydrogen for the subsequent hydrogen system. The second pressure control valve 18 adopts a solenoid valve with a pressure sensor to accurately control the working pressure of the reformer 6 and the palladium membrane separator 17 to ensure the normal progress of the high-pressure reforming reaction. At the same time, it can also be set according to the hydrogen pressure requirements of the hydrogen system. The separated tail gas of the palladium membrane separator 17 contains combustible gas, and some gases such as CO are harmful gases. The separated tail gas is passed to the burner 7, which can not only recover energy but also save the steps and equipment for treating the tail gas.

[0065] The palladium membrane separator 17 is also integrated with a first heater 16 for heating the palladium membrane separator 17 to maintain it within the optimal operating temperature range and to provide preheating for it when the system is started. The first heater is a radiation heater, and a patch heater can also be used. The palladium membrane separator 17 includes a plurality of palladium tubes in parallel. Depending on the system configuration, only one palladium tube can be provided, or a plurality of palladium tubes in series can be provided. The operating temperature range of the palladium membrane separator 17 is 400±20°C. Through the setting of the burner 7 and the heat exchanger 5, the temperature of the hydrogen-rich mixed gas output by the reformer 6 falls exactly within the operating temperature range of the palladium membrane separator 17, achieving efficient matching of the system.

[0066] Embodiment 2: A methanol-water reforming hydrogen production system.

[0067] like Figure 4 As shown, this embodiment omits the palladium membrane separator 17 and related devices on the basis of the first embodiment; Figure 5 and Figure 6 As shown, the reformer 6 and the burner 7 are plate-type reformers and plate-type burners, respectively, and reforming catalysts 603 and combustion catalysts 704 are respectively arranged inside. The plate-type reformers and the plate-type burners are alternately stacked, and the catalysts are arranged by filling or coating. The plate-type reformers and the plate-type burners are respectively arranged in parallel. According to different application scenarios, the plate-type reformers and the plate-type burners can also be arranged in series. Other settings are the same as those in Example 1.

[0068] When the hydrogen system has its own hydrogen purification system or uses other hydrogen purification systems, this embodiment can be used to obtain hydrogen-rich mixed gas. For example, this embodiment can be directly connected to a hydrogen system that uses pressure swing adsorption to purify hydrogen.

[0069] Embodiment 3: A methanol-water reforming hydrogen production system.

[0070] like Figure 7 As shown, based on the first embodiment, this embodiment further includes a second heater 19 disposed between the reformer 6 and the palladium membrane separator 17. The second heater 19 is a radiation heater, and a patch heater or a pipe built-in heater may also be used to fine-tune the temperature of the hydrogen-rich mixture to reduce the control difficulty of the burner 7 and make the temperature control of the hydrogen-rich mixture more accurate.

[0071] A methanation device 20 is also provided between the purified hydrogen outlet 1702 of the palladium membrane separator 17 and the second pressure control valve 18, for removing CO impurities in the purified hydrogen. The operating temperature range of the methanation device 20 is 300°C to 500°C. The methanation device can reduce the CO impurities in the purified hydrogen to below 0.2ppm, so that the purity of the hydrogen is greater than 99.9999%, to meet the requirements of hydrogen systems such as fuel cells. The purified hydrogen output by the palladium membrane separator 17 has a temperature of about 400°C and can be directly input into the methanation device for processing, making the system compact and efficient.

[0072] Embodiment 4: A control method for a methanol-water reforming hydrogen production system.

[0073] The methanol-water reforming hydrogen production system control method of this embodiment is used to control the methanol-water reforming hydrogen production system described in Embodiment 3, and comprises the following steps:

[0074] S10. Close the second methanol water inlet 501, that is, close the water pump 2 and the second flow control valve 9, start the methanol pump 10 and open the first flow control valve 8 to a larger opening, supply methanol as fuel to the first burner inlet 701, and at the same time, the air pump 11 supplies air to the first burner inlet 701; preheat the heat exchanger 5 and the reformer 6 to 400°C;

[0075] S11. When the reformer 6 is preheated to approximately 400°C, the first heater 16 is turned on to preheat the palladium membrane separator 17 to 400°C;

[0076] S20. After preheating is completed, the second flow control valve 9 and the water pump 2 are opened to provide methanol water to the second methanol water inlet 501; the hot side channel of the heat exchanger 5 is maintained above 400°C by controlling the burner 7, and the temperature of the methanol water mixed gas at the methanol water outlet 502 is controlled at 400°C to 420°C; the reformer 6 is maintained at 400°C to 420°C by controlling the burner 7, and the gas temperature of the hydrogen-rich mixed gas outlet 602 is also controlled at 400°C to 420°C;

[0077] S21. The palladium membrane separator 17 is maintained at 400±20°C by controlling the first heater 16, and the temperature of the gas entering the hydrogen-rich mixed gas inlet 1701 is controlled at 400°C to 420°C by controlling the second heater 19.

[0078] The control method of the methanol water reforming hydrogen production system described in Example 1 and Example 2 is similar to that of this embodiment. This application controls each process step accurately and efficiently at the optimal working temperature through reasonable system settings; the working temperatures of each process step match each other, and the system is easy to control; the system is also easy to modularize and integrate into various hydrogen systems.

[0079] The above are only preferred embodiments of the present application and the technical principles used. Various obvious changes, readjustments and substitutions can be made without departing from the concept of the present application. Those skilled in the art can easily understand other advantages and effects of the present application from the content disclosed in this specification. The present application can also be implemented or applied through other different specific implementation methods, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. In the absence of conflict, the above embodiments and the features in the embodiments can be combined with each other.

Claims

1. A methanol-water reforming hydrogen production system, comprising a reformer, a burner and a heat exchanger, characterized in that: The burner is a high-pressure catalytic combustion reactor, comprising a first burner inlet and a combustion tail gas outlet; The reformer comprises a first methanol-water inlet and a hydrogen-rich mixed gas outlet; The heat exchanger comprises a second methanol water inlet, a methanol water outlet, a combustion tail gas inlet, and an exhaust port; The methanol water outlet is connected to the first methanol water inlet, and the combustion tail gas outlet is connected to the combustion tail gas inlet; The reformer and the burner are integrated into one, specifically: Mode 1 or Mode 2: Mode 1: The reformer is a sleeve-type reformer, comprising an outer cylinder and an inner cylinder matched with each other, the cross-sections of the outer cylinder and the inner cylinder are polygonal, circular or oval, and a reforming catalyst is arranged between the outer cylinder and the inner cylinder; the inner cylinder also constitutes the outer shell of the burner, and a combustion catalyst is arranged in the outer shell; Mode 2: The reformer is a plate-type reformer, and a reforming catalyst is arranged inside; the burner is a plate-type burner, and a combustion catalyst is arranged inside; the plate-type reformer and the plate-type burner are alternately stacked, the plate-type reformers are arranged in parallel or in series, and the plate-type burners are arranged in parallel or in series; The methanol-water reforming hydrogen production system also includes a mixer with a stirring function, which is used to stir and mix methanol and water; It also includes a desalted water storage tank and a water pump for providing desalted water with a maximum pressure of more than 3.0 MPa to the mixer; It also includes a methanol storage tank and a methanol pump, which are used to provide methanol with a maximum pressure of more than 3.0 MPa to the mixer and the first burner inlet; It also includes an air source and an air pump, which are used to provide air with a maximum pressure of more than 3.0 MPa to the inlet of the first burner; The rated pressures of the mixer, the heat exchanger, and the reformer are not less than 3.0 MPa; It also includes a palladium membrane separator, which includes a hydrogen-rich mixed gas inlet, a purified hydrogen outlet, and a separator tail gas outlet; The palladium membrane separator comprises one palladium tube or multiple palladium tubes connected in parallel or in series; the operating temperature range of the palladium membrane separator is 400±20°C; The burner also includes a second burner inlet; The hydrogen-rich mixed gas inlet is connected to the hydrogen-rich mixed gas outlet, and the separator tail gas outlet is connected to the second burner inlet; The control method of the methanol-water reforming hydrogen production system comprises the steps of: S10. Close the second methanol water inlet, supply methanol as fuel to the first burner inlet, and preheat the heat exchanger and the reformer to not less than the lower limit of their respective operating temperatures; S20. Open the second methanol-water inlet, and maintain the mixer within its operating temperature range by controlling the burner, and control the temperature of the methanol-water mixed gas at the methanol-water outlet within a range of 400°C to 420°C; maintain the reformer within its operating temperature range by controlling the burner, and control the temperature of the hydrogen-rich mixed gas within a range of 400°C to 420°C.

2. The methanol-water reforming hydrogen production system according to claim 1, characterized in that: The water pump is a centrifugal pump, a turbine pump or a piston pump; The methanol pump is a metering pump; The air pump is a centrifugal pump, a turbine pump or a piston pump; The heat exchanger is a shell-and-tube type, a shell-and-tube type, or a microchannel type heat exchanger.

3. The methanol-water reforming hydrogen production system according to claim 1, characterized in that: The reforming catalyst is a high temperature reforming catalyst, and the operating temperature range is 300°C to 600°C; The maximum operating temperature of the combustion catalyst is not less than 600°C, and the maximum operating temperature of the heat exchanger is not less than 600°C.

4. The methanol-water reforming hydrogen production system according to claim 1, characterized in that: A first flow control valve is provided between the methanol storage tank and the first burner inlet, and a second flow control valve is provided between the methanol storage tank and the mixer; The exhaust port is provided with a first pressure control valve.

5. The methanol-water reforming hydrogen production system according to claim 4, characterized in that: The first flow control valve and the second flow control valve are needle valves; The first pressure control valve is a back pressure valve, or a solenoid valve matched with a pressure sensor.

6. The methanol-water reforming hydrogen production system according to claim 1, characterized in that: It also includes a first heater, which is integrated with the palladium membrane separator and is used to heat the palladium membrane separator; The first heater is a radiation heater or a patch heater.

7. The methanol-water reforming hydrogen production system according to claim 6, characterized in that: Also included is a second heater, the second heater being disposed between the hydrogen-rich mixed gas outlet and the hydrogen-rich mixed gas inlet; The second heater is a radiation heater, a patch heater or a pipeline built-in heater.

8. The methanol-water reforming hydrogen production system according to claim 7, characterized in that: A third flow control valve is provided between the separator tail gas outlet and the second burner inlet, and the purified hydrogen outlet is connected to a second pressure control valve.

9. The methanol-water reforming hydrogen production system according to claim 8, characterized in that: It also includes a methanation device, which is arranged between the purified hydrogen outlet and the second pressure control valve, and the operating temperature range of the methanation device is 300°C to 500°C.

10. The methanol-water reforming hydrogen production system according to claim 7, 8 or 9, characterized in that: The control method of the methanol water reforming hydrogen production system further includes step S11 between step S10 and step S20, and step S21 after step S20: S11. Before step S10 ends, the first heater is turned on to heat the palladium membrane separator to a temperature not lower than the lower limit of its operating temperature range; S21. Maintain the palladium membrane separator within its operating temperature range by controlling the first heater, and control the temperature of the gas entering the hydrogen-rich mixed gas inlet within the operating temperature range of the palladium membrane separator by controlling the second heater.

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