A methanol-water fuel reforming hydrogen production system

Abstract

The present invention provides a methanol water fuel reforming hydrogen production system, which includes a catalytic burner, a reformer, a water vapor converter, a selective oxidizer, a fuel storage tank and a fuel cell connected in sequence. The present invention performs phased oxidation treatment on the hydrogen-rich mixed gas through the water vapor converter and the selective oxidizer, gradually reduces the CO concentration in the gas, and ensures that CO is completely removed. The system of the present invention takes a short time to start up, can quickly reach the reforming hydrogen production conditions, has low energy consumption, fast hydrogen production speed, low hydrogen production cost, has high energy conversion efficiency, is environmentally friendly and energy-saving, and has a high power generation efficiency after docking with a fuel cell stack.

Description

Technical Field

[0001] The invention relates to the technical field of methanol reforming hydrogen production, and in particular to a methanol water fuel reforming hydrogen production system. Background Art

[0002] Energy and environment have become the primary issues facing the development of countries around the world. The advent of hybrid vehicles and fuel cell vehicles that use hydrogen as energy has provided a practical and effective solution to alleviate the energy crisis and protect the environment. Further improving the efficiency of on-board hydrogen production to provide a high-purity hydrogen source for fuel cells has gradually become a focus of attention. Methanol has the advantages of high hydrogen content, no sulfur, low carbon monoxide (CO) content in the reforming product, and low reaction temperature. It has always been an important raw material for reforming hydrogen. The mixed gas produced by the methanol steam reforming reaction has a high hydrogen content and is currently the most commonly used reforming hydrogen production method. The mechanism of hydrogen production by methanol steam reforming is to use methanol and water vapor under the action of a catalyst to produce a methanol reforming chemical reaction to prepare a hydrogen-rich mixed gas.

[0003] In the existing methanol reforming hydrogen production system, the temperature of the carbon monoxide CO separation device is generally above 400°C, and palladium membrane, palladium alloy membrane or palladium composite membrane is used. Among them, although the palladium membrane has good selectivity for hydrogen, the palladium membrane is expensive, and the hydrogen embrittlement phenomenon is serious, the service life is short, and the hydrogen permeation rate is low, resulting in low purification efficiency, and the purification efficiency is only about 75%, causing great energy resource loss. The hydrogen permeability of the palladium alloy membrane (mainly palladium silver, palladium yttrium alloy) is not high, and the mechanical properties are poor. When it is greater than 500°C, it is easy to grow grains, and the membrane service life is short, which still cannot meet the actual requirements of high-purity hydrogen purification and separation. In addition, the purification of palladium and its alloy membranes has high requirements for power equipment, requiring operation under pressure conditions above 1MPa, and the expansion is difficult and the overall compactness of the equipment is reduced after expansion. The palladium composite membrane (supported palladium membrane) is made by loading the palladium metal membrane on the surface of a porous material (ceramic, quartz, stainless steel, etc.). However, although the palladium composite membrane has low cost, high purification efficiency and large output, the purity of hydrogen separated by the palladium composite membrane is low. The purity of the produced hydrogen is generally only about 99%, and it is difficult to reach above 99.999%. Summary of the invention

[0004] In order to solve the deficiencies existing in the above-mentioned prior art, the purpose of the present invention is to provide a methanol-water fuel reforming hydrogen production system, which can ultimately completely remove CO in the reformed hydrogen-rich mixed gas, thereby improving the purification efficiency of hydrogen and reducing the purification cost.

[0005] In order to solve the above technical problems, an embodiment of the present invention provides a methanol-water fuel reforming hydrogen production system, including a catalytic burner, a reformer, a water-gas converter, a selective oxidizer, a fuel storage tank and a fuel cell;

[0006] The outlet of the fuel storage tank is connected to the inlet of the reformer and the liquid fuel inlet of the catalytic burner through a liquid fuel pipe; the outlet of the reformer is connected to the inlet of the water-gas converter, the outlet of the water-gas converter is connected to the inlet of the selective oxidizer, the outlet of the selective oxidizer is connected to the inlet of the fuel cell stack, and the hydrogen-rich outlet of the fuel cell stack is connected to the gas fuel inlet of the catalytic burner.

[0007] Furthermore, the catalytic burner, the reformer, the water-steam converter, and the selective oxidizer are all arranged horizontally, and the reformer is arranged above the burner, the water-steam converter is arranged above the reformer, and the selective oxidizer is arranged above the water-steam converter.

[0008] Furthermore, a preheating vaporization exhaust flue is provided above the reformer and below the water-steam converter, and the outlet of the catalytic burner is connected to the inlet of the preheating vaporization exhaust flue;

[0009] A preheating vaporization coil is arranged in the preheating vaporization exhaust flue, and the outlet of the fuel storage tank is connected to the inlet of the reformer through the liquid fuel pipe and the preheating vaporization coil in sequence.

[0010] Furthermore, a heat exchange exhaust duct is provided above the preheating vaporization exhaust duct and below the water vapor converter, the outlet of the preheating vaporization exhaust duct is connected to the inlet of the heat exchange exhaust duct, and a first thermal insulation cotton is provided between the preheating vaporization exhaust duct and the heat exchange exhaust duct.

[0011] Furthermore, a second thermal insulation cotton is provided between the water vapor converter and the selective oxidizer, a first electric heating plate is provided on the lower side of the second thermal insulation cotton near the water vapor converter, and a second electric heating plate is provided on the upper side of the second thermal insulation cotton near the selective oxidizer; a cooling fan is provided above the selective oxidizer.

[0012] Furthermore, insulation plates are provided on the upper and lower sides of the reformer, and the space between the insulation plates on the upper and lower sides of the reformer forms a reforming chamber, and the reforming chamber is divided into a plurality of reaction chambers, and the plurality of reaction chambers are connected in sequence to form a reaction bed flow channel, and the reaction bed flow channel is filled with a reforming catalyst.

[0013] Furthermore, the upper and lower sides of the water vapor converter are both provided with heat insulation plates, and the space between the heat insulation plates on the upper and lower sides of the water vapor converter forms a water vapor conversion reaction chamber and a water vapor conversion cooling chamber, wherein the side of the water vapor converter close to the inlet is the water vapor conversion reaction chamber, and the side of the water vapor converter close to the outlet is the water vapor conversion cooling chamber;

[0014] The water vapor shift reaction chamber is divided into a plurality of reaction chambers, wherein the plurality of reaction chambers are sequentially connected to form a reaction bed flow channel, and the reaction bed flow channel is filled with a water vapor shift catalyst;

[0015] The water vapor conversion cooling chamber is divided into a plurality of cooling chambers, and the plurality of cooling chambers are sequentially connected to form a cooling flow channel.

[0016] Furthermore, heat insulation plates are provided on the upper and lower sides of the selective oxidizer, and the space between the heat insulation plates on the upper and lower sides of the selective oxidizer forms a selective oxidation chamber, and the selective oxidation chamber is divided into a plurality of reaction chambers, and the plurality of reaction chambers are connected in sequence to form a reaction bed flow channel, and the reaction bed flow channel is filled with a selective oxidation catalyst.

[0017] Furthermore, the upper and lower sides of the catalytic burner are provided with heat insulation plates, and the space between the upper and lower heat insulation plates of the catalytic burner forms a catalytic combustion chamber, and the catalytic combustion chamber is divided into multiple combustion chambers, and the multiple reaction chambers are connected in sequence to form a combustion flow channel, and the combustion flow channel is filled with catalytic combustion catalyst.

[0018] Furthermore, a catalytic burner solenoid valve, a fuel solenoid valve and a liquid delivery pump are sequentially provided on the liquid fuel pipe in the direction from the liquid fuel inlet to the fuel storage tank; a fuel heating rod is provided in the liquid fuel pipe between the liquid fuel inlet and the catalytic burner solenoid valve.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. The hydrogen-rich mixed gas prepared by the system of the present invention is subjected to staged catalytic oxidation treatment through a water vapor converter and a selective oxidizer, thereby gradually reducing the CO concentration in the hydrogen-rich mixed gas. The combined catalytic oxidation has a good purification effect on hydrogen, high purification efficiency, and low purification cost.

[0021] 2. The present invention optimizes the flow paths of the liquid channel and gas channel of the system, fully recycles the tail gas of the fuel cell stack, and uses the combustion heat generated by the fuel cell stack to provide the heat required for the operation of the system. At the same time, the heat of the combustion tail gas is used to heat the methanol water fuel, maintain the balance of heat in the system, and meet the system's own heating needs. The combustion tail gas after heat exchange and cooling can also be used as a cold source to cool the hydrogen-rich mixed gas in the water vapor converter to ensure the removal effect of CO. Therefore, the present invention significantly reduces the energy consumption of the methanol reforming hydrogen production system, fully recycles the energy, and also reduces the emission temperature of the system's combustion tail gas to meet the emission requirements.

[0022] 3. The conversion rate of methanol in the system of the present invention can reach 100%, and CO in the reformed mixed gas can be completely removed. The system takes a short time to start up and can quickly reach the reforming hydrogen production conditions. It has low energy consumption, fast hydrogen production speed, low hydrogen production cost, high energy conversion efficiency, environmental protection and energy saving. After docking with the fuel cell stack, the power generation efficiency is relatively high.

[0023] 4. The system structure of the present invention is compact, and the functions of each module are clearly distinguished. The capacity can be expanded by combining multiple modules to increase the output power, thereby reducing the production cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a structural schematic diagram of a methanol-water fuel reforming hydrogen production system provided in one embodiment of the present invention;

[0025] Figure 2 This is a process flow chart of a methanol-water fuel reforming hydrogen production system provided by an embodiment of the present invention;

[0026] The reference numerals are as follows:

[0027] Fan 1-1, air duct 1-2, combustion pipeline 1-3, preheating vaporization exhaust flue inlet 1-4, preheating vaporization exhaust flue 1-5, preheating vaporization exhaust flue outlet 1-6, flue gas duct 1-7, heat exchange exhaust flue inlet 1-8, heat exchange exhaust flue 1-9, heat exchange exhaust flue outlet 1-10, exhaust duct 1-11, selective oxidation air fan 1-12, air solenoid valve 1-14;

[0028] Fuel storage tank 2-1, liquid delivery pump 2-3, fuel solenoid valve 2-5-1, catalytic burner solenoid valve 2-5-2, reformer solenoid valve 2-5-3, fuel heating rod 2-8, preheating vaporization coil 2-10;

[0029] Gas product pipe 3-1, gas heat exchanger 3-4, gas product solenoid valve 3-6;

[0030] Selective oxidizer 5; selective oxidation chamber 5-3, selective oxidizer inlet 5-4, selective oxidizer outlet 5-5;

[0031] Water vapor converter 6; water vapor converter reaction chamber 6-3, water vapor converter cooling chamber 6-4, water vapor converter inlet 6-5, water vapor converter outlet 6-6;

[0032] Reformer 7; reformer inlet 7-1, reformer outlet 7-2, reforming chamber 7-3;

[0033] Catalytic burner 8; liquid fuel inlet 8-1, hydrogen fuel inlet 8-2, air inlet 8-3, catalytic burner outlet 8-4, catalytic combustion chamber 8-5;

[0034] A first electric heating plate 9-1 and a second electric heating plate 9-2;

[0035] Heat insulation board 10, fuel cell stack 11, cooling fan 12, second heat insulation cotton 13-1, first heat insulation cotton 13-2. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] See also Figure 1 and Figure 2 , the technical solution adopted by the present invention is:

[0038] First, the present invention provides a carbon monoxide removal device using the principle of chemical catalytic reaction, which includes a water vapor converter (CO Low Temperature Shift, referred to as CO-LTS) and a selective oxidizer (CO Preferential Oxidation, referred to as CO-PROX), wherein a water vapor converter catalyst is provided inside the CO-LTS water vapor converter, and a selective oxidation catalyst is provided inside the CO-PROX selective oxidizer. The CO chemical removal device can be used to remove CO from the reformed hydrogen-rich mixed gas, and the CO content in the mixed gas is reduced to a certain standard through LTS technology (water gas shift reaction) and PROX technology (CO selective oxidation) to meet the use restriction requirements of the fuel cell stack. This process is a gas-solid phase catalytic reaction with multiple components and multiple side reactions.

[0039] Preferably, the present invention first uses the water vapor converter 6 to perform a primary treatment on the hydrogen-rich mixed gas, so that CO reacts with H2O to generate CO2 and H2, thereby removing most of the CO in the mixed gas. The specific reaction principle is shown in formula (1); then, the present invention uses the selective oxidizer 5 to perform a secondary treatment on the hydrogen-rich mixed gas, and at the same time, air is introduced into the selective oxidizer 5 to completely remove the residual CO in the mixed gas. The specific reaction principle is shown in formulas (2) and (3).

[0040] CO+H2O→CO2+H2 Formula (1),

[0041]

[0042] Preferably, the water vapor converter 6 is used to generate a water vapor shift chemical reaction of carbon monoxide and water (CO Low Temperature Shift, abbreviated as CO-LTS). The water vapor converter 6 is composed of a space surrounded by insulation plates on its upper and lower sides to form a water vapor shift reaction chamber 6-3 and a water vapor shift cooling chamber 6-4; a water vapor converter inlet 6-5 and a water vapor converter outlet 6-6 are respectively provided at both ends of the water vapor converter 6.

[0043] Preferably, the water vapor converter 6 is located at the upper part of the preheating vaporization exhaust flue 1-5, the lower part of the water vapor converter 6 is provided with a heat exchange exhaust flue 1-9 for the circulation of the combustion gas of the catalytic burner 8, and the tail part of the water vapor converter 6 is provided with a water vapor conversion cooling chamber 6-4 for heat exchange with the heat exchange exhaust flue 1-9; the preheating vaporization exhaust flue 1-5 and the heat exchange exhaust flue 1-9 are separated by the first thermal insulation cotton 13-2.

[0044] Preferably, the water vapor shift reaction chamber 6 - 3 is divided into different reaction chambers, and the reaction chambers are sequentially connected to form a continuous reaction bed flow channel, and the reaction bed flow channel is filled with a water vapor shift catalyst; the catalyst can be obtained through commercial channels.

[0045] Preferably, the water vapor conversion cooling chamber 6-4 is divided into different cooling chambers, which are sequentially connected to form a continuous cooling channel, and the lower part of the cooling channel is close to the heat exchange exhaust flue 1-9, and performs heat exchange with the fluid flowing therein; the structural form of the water vapor conversion cooling chamber 6-4 can be S-shaped, rectangular, non-shaped, etc. The water vapor conversion cooling chamber 6-4 is used to cool the hydrogen-rich mixed gas discharged from the water vapor converter 6, so that the hydrogen-rich mixed gas entering the selective oxidizer 5 is below 200°C, thereby ensuring the reliability and durability of the selective oxidizer 5.

[0046] Preferably, the selective oxidizer 5 is used for the selective catalytic oxidation chemical reaction of carbon monoxide and oxygen (CO Preferential Oxidation, referred to as CO-PROX), and the selective oxidizer 5 is formed by a space surrounded by heat insulation plates on both sides thereof to form a selective oxidation chamber 5-3; the selective oxidizer 5 is provided with a selective oxidizer inlet 5-4 and a selective oxidizer outlet 5-5;

[0047] Preferably, the selective oxidizer 5 is located on the upper part of the water vapor converter 6, and the selective oxidizer 5 and the water vapor converter 6 are separated by the second heat-insulating cotton 13-1; the first electric heating plate 9-1 with heating function is arranged on the lower side of the second heat-insulating cotton 13-1 near the water vapor converter 6, and the second electric heating plate 9-2 with heating function is arranged on the upper side of the second heat-insulating cotton 13-1 near the selective oxidizer 5; a cooling fan is arranged on the upper part of the selective oxidizer 5. In this way, the reaction temperature inside the selective oxidizer 5 can be further reduced;

[0048] Preferably, the selective oxidation chamber 5-3 is divided into different reaction chambers, which are sequentially connected to form a continuous reaction bed flow channel, and the reaction bed flow channel is filled with a selective oxidation catalyst; the ruthenium-based catalyst can be obtained through commercial channels.

[0049] In addition, the present invention also provides a methanol water fuel reforming hydrogen production system, which includes a catalytic burner 8, a reformer 7, a water vapor converter 6, a selective oxidizer 5 connected in sequence, and a gas combustion pipeline, a liquid fuel pipeline, a gas product pipeline, a liquid cooling pipeline and a heating plate with auxiliary functions, a heat insulation board and a fuel cell, a heat dissipation fan 12, a heat insulation cotton, etc.

[0050] Preferably, the catalytic burner 8 is located at the bottom of the methanol-water fuel reforming hydrogen production system, and releases heat through the catalytic combustion chemical reaction to provide heat for the entire system. The catalytic burner 8 is composed of a space surrounded by upper and lower insulation plates to form a catalytic combustion chamber 8-5, and the catalytic combustion chamber 8-5 is divided into different combustion chambers, which are sequentially connected to form a continuous combustion flow channel, and the combustion flow channel is filled with a catalytic combustion catalyst; the catalytic combustion catalyst components include but are not limited to platinum-based catalysts, ruthenium-based catalysts, manganese-based catalysts, cobalt-based catalysts, composite oxides, etc., and the catalytic combustion catalyst shapes include but are not limited to spherical, flaky, cylindrical and shaped granular catalysts, integral catalysts, etc.;

[0051] Preferably, the catalytic burner 8 is provided with a liquid fuel inlet 8-1, a hydrogen fuel inlet 8-2, an air inlet 8-3, and a catalytic burner outlet 8-4; the air inlet 8-3 is connected to the fan 1-1 through the air duct 1-2;

[0052] Preferably, the liquid fuel inlet 8-1 is connected to the fuel storage tank 2-1 through the catalytic burner solenoid valve 2-5-2, the fuel solenoid valve 2-5-1, and the liquid delivery pump 2-3 on the liquid fuel pipe in sequence; the fuel feed pipe is provided with a fuel heating rod 2-8 for heating and vaporizing the liquid fuel;

[0053] Preferably, the catalytic burner outlet 8-4 is connected to the inlet of the preheating vaporization exhaust flue 1-5 through the combustion pipeline 1-3, and after passing through the preheating vaporization exhaust flue 1-5, it passes through the preheating vaporization exhaust flue outlet 1-6, and is connected to the inlet of the heat exchange exhaust flue 1-9 through the flue gas pipeline 1-7. The heat exchange exhaust flue inlet 1-8, after passing through the heat exchange exhaust flue 1-9, is connected to the exhaust pipe 1-11 through the heat exchange exhaust flue outlet 1-10 and discharged outside the system;

[0054] Preferably, the reformer 7 is located above the catalytic burner 8, and is used for a chemical reaction of reforming methanol and water to produce hydrogen; the space surrounded by the insulation plates on the upper and lower sides of the reformer 7 constitutes a reforming chamber 7-3; the reformer 7 is provided with a reformer inlet 7-1 and a reformer outlet 7-2 at both ends; the reformer 7 and the catalytic burner 8 are separated by an insulation plate;

[0055] Preferably, the reformer inlet 7-1 is connected to the fuel storage tank 2-1 through the preheating vaporization coil 2-10, the reformer solenoid valve 2-5-3, the fuel solenoid valve 2-5-1, and the liquid delivery pump 2-3;

[0056] Preferably, the reforming chamber 7-3 is divided into different reaction chambers, and the reaction chambers are sequentially connected to form a continuous reaction bed flow channel, and the reaction bed flow channel is filled with a reforming catalyst; the reforming catalyst composition includes but is not limited to a copper-based catalyst, a zirconium-based catalyst, a chromium-based catalyst, a zinc-based catalyst, etc., and the reforming catalyst shape includes but is not limited to a spherical, sheet-like, cylindrical and shaped granular catalyst, a monolithic catalyst, etc.;

[0057] Preferably, the upper part of the reformer 7 is provided with a preheating vaporization exhaust flue 1-5 for the combustion gas of the catalytic burner 8 to flow; the preheating vaporization exhaust flue 1-5 is provided with a preheating vaporization coil 2-10 for heating the liquid fuel;

[0058] Preferably, the preheating vaporization coil 2-10 is located in the preheating vaporization exhaust flue 1-5; the preheating vaporization coil is in the form of an S-shape, a rectangle, a non-shape, etc.;

[0059] Preferably, the reformer outlet 7-2 is connected to the inlet 6-5 of the water-gas converter 6 through the gas product pipe 3-1;

[0060] Preferably, the selective oxidizer inlet 5-4 delivers air into the selective oxidizer through the selective oxidation fan 1-12 and the air solenoid valve 1-14 on the air pipeline.

[0061] Preferably, the heat exchanger is a serpentine heat exchanger, a spiral tube heat exchanger or a brazed plate heat exchanger;

[0062] Preferably, the methanol-water fuel is a mixture of methanol and water, and the methanol content of the mixed solution is in the range of 30%-80%.

[0063] Based on the above scheme, the working process of the reforming hydrogen production system of the present invention is as follows:

[0064] During the startup phase, methanol-water fuel enters the liquid, is heated and vaporized by the electric heating device, and then is supplied to the catalytic burner to start combustion and heat supply. When the bed temperature of the reformer rises to a certain temperature, the control valve of the liquid channel is opened to supply methanol-water fuel to the reformer for reforming and hydrogen production. The methanol-water fuel is preheated in the preheater, heated and vaporized, and then enters the bed of the reformer for reforming and hydrogen production.

[0065] After the hydrogen-rich gas prepared by reforming the methanol-water fuel passes through the fuel cell stack, part of the unreacted hydrogen-rich gas is recovered through the gas pipeline and enters the burner for combustion. The heat released by the combustion of the hydrogen-rich gas is used to heat the methanol-water fuel before entering the reformer, and the combustion exhaust gas is used to perform a primary heat exchange with the gas-liquid mixture in the heat exchanger and the reformer to heat the gas-liquid mixture. The combustion exhaust gas then enters the preheater along the gas channel for a secondary heat exchange to heat the methanol-water fuel in the preheater. The combustion exhaust gas then enters the water-gas converter 6 along the gas channel for a partition heat exchange to reduce the temperature of the hydrogen-rich mixed gas in the water-gas converter 6, thereby reducing the catalytic oxidation temperature of the water-gas converter 6, and achieving the purpose of removing CO by low-temperature catalytic oxidation of the catalyst in the LTS. Finally, the combustion exhaust gas is diluted by air convection and discharged to the outside.

[0066] Specifically, the working process of the reforming hydrogen production system of this embodiment is as follows:

[0067] During the startup phase, the fuel solenoid valve 2-5-1 and the catalytic burner solenoid valve 2-5-2 are opened, and the liquid delivery pump 2-3 delivers the methanol and water mixed solution fuel in the fuel storage tank 2-1 into the liquid fuel inlet 8-1 through the fuel feed pipe. After being heated and vaporized by the fuel heating rod 2-8, the fuel is passed through the liquid fuel inlet 8-1 into the catalytic combustion catalyst bed in the catalytic combustion chamber 8-5 for catalytic combustion reaction, releasing heat to provide energy for the system.

[0068] The catalytic burner 8 generates heat radiation and high-temperature flue gas through the catalytic combustion reaction. The generated high-temperature flue gas passes through the catalytic burner outlet 8-4, passes through the combustion pipeline 1-3, and enters the preheating vaporization exhaust flue 1-5 through the preheating vaporization exhaust flue inlet 1-4. The heat radiation and high-temperature flue gas heat the insulation plates on the upper and lower sides; the reformer 7 increases the temperature through the heat conduction of the insulation plates on the upper and lower sides; after passing through the preheating vaporization exhaust flue 1-5, it passes through the preheating vaporization exhaust flue outlet 1-6, passes through the flue gas pipeline 1-7 and is connected to the inlet of the heat exchange exhaust flue 1-9, the heat exchange exhaust flue inlet 1-8, and after passing through the heat exchange exhaust flue 1-9, it passes through the heat exchange exhaust flue outlet 1-10 and is connected to the exhaust pipe 1-11 and is discharged outside the system.

[0069] When the temperature of the reforming catalyst bed of the reformer 7 rises to a certain temperature, the reformer solenoid valve 2-5-3 is opened, and the methanol fuel enters the preheating vaporization coil 2-10 through the liquid fuel pipe; at the same time, the high-temperature flue gas in the preheating vaporization exhaust flue 1-5 and the preheating vaporization coil 2-10 located in the preheating vaporization exhaust flue 1-5 perform heat exchange heating to vaporize the liquid fuel in the preheating vaporization coil 2-10. After preheating and vaporization, the methanol water fuel enters the reforming catalyst bed in the reforming chamber 7-3 through the reformer inlet 7-1 to undergo chemical reforming reaction to produce a hydrogen-rich mixed gas product.

[0070] The hydrogen-rich mixed gas product produced by the reformer 7 passes through the reformer outlet 7-2 and the gas product pipe 3-1 (SR), and enters the water-gas converter 6 through the water-gas converter inlet 6-5. Under the action of the water-gas converter catalyst in the water-gas converter reaction chamber 6-3, the carbon monoxide (CO) in the hydrogen-rich mixed gas entering the water-gas converter 6 is consumed by the chemical reaction in formula (1), resulting in a decrease in its concentration. The primary purified gas after the reaction enters the water-gas converter cooling chamber 6-4 from the water-gas converter reaction chamber 6-3, and in the process of passing through the water-gas converter cooling chamber 6-4, performs a wall-type heat exchange with the heat exchange exhaust flue 1-9, thereby causing the temperature to decrease. After the temperature is reduced, the gas enters the selective oxidizer 5 from the water-gas converter outlet 6-6 through the gas product pipe (LTS) and the selective oxidizer inlet 5-4;

[0071] After being purified by the first-stage purified gas (CO-LTS), it enters the selective oxidation chamber 5-3 in the selective oxidizer 5. Under the action of the selective oxidation catalyst, the carbon monoxide (CO) therein is consumed through the chemical reaction in formula (2) (3), and its concentration is further reduced. The secondary purified gas after the reaction passes through the selective oxidizer outlet 5-5 through the gas product pipe (PROX), the gas heat exchanger 3-4, the gas product pipe, the gas product solenoid valve 3-6, and the gas product pipe into the fuel cell stack 11 for power generation; the excess hydrogen-rich gas after power generation by the fuel cell stack 11 is connected to the gas fuel inlet 8-2 through the gas product pipe and introduced into the catalytic burner for combustion to provide heat for the system.

[0072] Compared with the prior art, the present invention has the following beneficial effects:

[0073] 1. The hydrogen-rich mixed gas prepared by the system of the present invention is subjected to staged catalytic oxidation treatment through a water vapor converter and a selective oxidizer, thereby gradually reducing the CO concentration in the hydrogen-rich mixed gas. The combined catalytic oxidation of LTS and PROX has a good purification effect on hydrogen, high purification efficiency, and low purification cost. The present invention also performs cooling and temperature control treatment on the water vapor converter stage and the selective oxidation stage to ensure that the purification of H2 is reliable and durable.

[0074] 2. The present invention optimizes the flow paths of the liquid channel and gas channel of the system, fully recycles the tail gas of the fuel cell stack, and uses the combustion heat generated by the fuel cell stack to provide the heat required for the operation of the system. At the same time, the heat of the combustion tail gas is used to heat the methanol water fuel, maintain the balance of heat in the system, and meet the system's own heating needs. The combustion tail gas after heat exchange and cooling can also be used as a cold source to cool the hydrogen-rich mixed gas in the water vapor converter to ensure the removal effect of CO. Therefore, the present invention significantly reduces the energy consumption of the methanol reforming hydrogen production system, fully recycles the energy, and also reduces the emission temperature of the system's combustion tail gas to meet the emission requirements.

[0075] 3. The conversion rate of methanol in the system of the present invention can reach 100%, and CO in the reformed mixed gas can be completely removed. The system takes a short time to start up and can quickly reach the reforming hydrogen production conditions. It has low energy consumption, fast hydrogen production speed, low hydrogen production cost, high energy conversion efficiency, environmental protection and energy saving. After docking with the fuel cell stack, the power generation efficiency is relatively high.

[0076] 4. The system structure of the present invention is compact, and the functions of each module are clearly distinguished. The capacity can be expanded by combining multiple modules to increase the output power, thereby reducing production costs.

[0077] The above is a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the principle of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A methanol-water fuel reforming hydrogen production system, characterized in that: Includes catalytic burners, reformers, water-gas converters, selective oxidizers, fuel storage tanks, and fuel cells; The outlet of the fuel storage tank is connected to the inlet of the reformer and the liquid fuel inlet of the catalytic burner through a liquid fuel pipe; the outlet of the reformer is connected to the inlet of the water-gas converter, the outlet of the water-gas converter is connected to the inlet of the selective oxidizer, the outlet of the selective oxidizer is connected to the inlet of the fuel cell stack, and the hydrogen-rich outlet of the fuel cell stack is connected to the gas fuel inlet of the catalytic burner; The catalytic burner, the reformer, the water-steam converter, and the selective oxidizer are all arranged horizontally, and the reformer is arranged above the burner, the water-steam converter is arranged above the reformer, and the selective oxidizer is arranged above the water-steam converter; A preheating vaporization exhaust flue is provided above the reformer and below the water vapor converter, and the outlet of the catalytic burner is connected to the inlet of the preheating vaporization exhaust flue; a preheating vaporization coil is provided in the preheating vaporization exhaust flue, and the outlet of the fuel storage tank is connected to the inlet of the reformer through the liquid fuel pipe and the preheating vaporization coil in sequence; A second thermal insulation cotton is provided between the water vapor converter and the selective oxidizer, a first electric heating plate is provided on the lower side of the second thermal insulation cotton near the water vapor converter, and a second electric heating plate is provided on the upper side of the second thermal insulation cotton near the selective oxidizer; a cooling fan is provided above the selective oxidizer.

2. The methanol-water fuel reforming hydrogen production system according to claim 1, characterized in that: A heat exchange exhaust duct is provided above the preheating vaporization exhaust duct and below the water vapor converter, the outlet of the preheating vaporization exhaust duct is connected to the inlet of the heat exchange exhaust duct, and a first thermal insulation cotton is provided between the preheating vaporization exhaust duct and the heat exchange exhaust duct.

3. The methanol-water fuel reforming hydrogen production system according to claim 1, characterized in that: The reformer is provided with heat insulation plates on the upper and lower sides, and the space between the heat insulation plates on the upper and lower sides of the reformer forms a reforming chamber, which is divided into a plurality of reaction chambers, and the plurality of reaction chambers are connected in sequence to form a reaction bed flow channel, and the reaction bed flow channel is filled with a reforming catalyst.

4. The methanol-water fuel reforming hydrogen production system according to claim 1, characterized in that: The upper and lower sides of the water vapor converter are both provided with heat insulation plates, and the space between the upper and lower heat insulation plates of the water vapor converter forms a water vapor conversion reaction chamber and a water vapor conversion cooling chamber, wherein the side of the water vapor converter close to the inlet is the water vapor conversion reaction chamber, and the side of the water vapor converter close to the outlet is the water vapor conversion cooling chamber; The water vapor shift reaction chamber is divided into a plurality of reaction chambers, wherein the plurality of reaction chambers are sequentially connected to form a reaction bed flow channel, and the reaction bed flow channel is filled with a water vapor shift catalyst; The water vapor conversion cooling chamber is divided into a plurality of cooling chambers, and the plurality of cooling chambers are sequentially connected to form a cooling flow channel.

5. The methanol-water fuel reforming hydrogen production system according to claim 1, characterized in that: The selective oxidizer is provided with heat insulation plates on the upper and lower sides, and the space between the heat insulation plates on the upper and lower sides of the selective oxidizer forms a selective oxidation chamber. The selective oxidation chamber is divided into a plurality of reaction chambers, and the plurality of reaction chambers are connected in sequence to form a reaction bed flow channel, and the reaction bed flow channel is filled with a selective oxidation catalyst.

6. The methanol-water fuel reforming hydrogen production system according to claim 1, characterized in that: The upper and lower sides of the catalytic burner are both provided with heat insulation plates, and the space between the upper and lower heat insulation plates of the catalytic burner forms a catalytic combustion chamber, and the catalytic combustion chamber is divided into multiple combustion chambers, and the multiple reaction chambers are connected in sequence to form a combustion flow channel, and the combustion flow channel is filled with catalytic combustion catalyst.

7. The methanol-water fuel reforming hydrogen production system according to claim 1, characterized in that: The liquid fuel pipe is provided with a catalytic burner solenoid valve, a fuel solenoid valve and a liquid delivery pump in sequence from the liquid fuel inlet to the fuel storage tank; a fuel heating rod is provided in the liquid fuel pipe between the liquid fuel inlet and the catalytic burner solenoid valve.

Images