Methanol reforming hydrogen production and power generation system and method suitable for extreme environment

Abstract

The invention relates to a methanol reforming hydrogen production and power generation system and method suitable for an extreme environment. The system comprises a first storage tank, a second storage tank, a gasifier, a reforming reactor, a CO removal reactor and a fuel cell stack. Respectively heating the gasifier, the reforming reactor and the CO removal reactor to respective working temperatures through a chemical looping combustion and catalytic combustion technology of air and methanol; a methanol aqueous solution is gasified through a gasifier to form methanol steam, and then the methanol steam enters a reforming reactor to be subjected to a methanol steam reforming reaction to generate reformed hydrogen; the reformed hydrogen enters a CO removal reactor for CO removal, the reformed hydrogen subjected to CO removal enters a fuel cell stack for power generation, anode tail gas of the stack respectively enters a gasifier and a reforming reactor to be subjected to catalytic combustion reaction with air, and heat released by the reaction is used for gasification and reforming reaction of a methanol aqueous solution; therefore, the system efficiency and the environmental adaptability are improved under the condition that external assistance is not needed.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of hydrogen production by methanol reforming, and particularly relates to a hydrogen production by methanol reforming system and method suitable for extreme environment. BACKGROUND

[0002] Under extreme environment (such as polar, plateau, deep sea or military application), traditional hydrogen production and power generation technology faces severe challenges, including difficult low-temperature start, low system efficiency, poor fuel adaptability and other problems. Methanol reforming hydrogen production technology is considered as a feasible solution due to its convenient fuel storage and transportation and high energy density, but the existing system usually relies on external heat source or electric heating to maintain the reaction temperature, resulting in high energy consumption, complex system and difficulty in stable operation under harsh conditions. In addition, the CO removal efficiency in the traditional reforming hydrogen production process is insufficient, which easily poisons the fuel cell catalyst and affects the power generation performance. Although in recent years, chemical looping combustion, catalytic combustion and tail gas heat recovery technologies have been introduced to optimize system thermal management, there are still problems such as inaccurate reactor temperature control and low heat utilization rate under extreme temperature fluctuations or low oxygen environment. SUMMARY

[0003] In order to overcome the problems existing in the prior art, the present application provides a hydrogen production by methanol reforming system and method suitable for extreme environment, which is used to overcome the existing defects.

[0004] A hydrogen production by methanol reforming system suitable for extreme environment, the system comprises: a first storage tank, a second storage tank, a gasifier, a reforming reactor, a CO removal reactor and a fuel cell stack, wherein the first storage tank stores methanol, the second storage tank stores methanol aqueous solution, the first storage tank and the second storage tank are connected with the gasifier and the reforming reactor at the same time, respectively used for providing methanol and methanol aqueous solution;

[0005] The gasifier and the reforming reactor are connected, air and methanol undergo chemical chain combustion and catalytic combustion chemical reaction in the gasifier, and the heat generated by the chemical reaction is used for gasification of methanol and methanol aqueous solution;

[0006] The reforming reactor is connected with the CO removal reactor, air and methanol undergo chemical chain combustion and catalytic combustion chemical reaction in the reforming reactor, and the heat generated by the chemical reaction is used to provide heat for the hydrogen production process of methanol steam reforming;

[0007] The CO removal reactor is connected with the fuel cell stack, used for removing CO in the reforming hydrogen, and the reforming hydrogen after removing CO is input into the fuel cell stack;

[0008] The fuel cell stack uses the received reforming hydrogen to generate electricity.

[0009] According to the aspect and any possible implementation manner thereof, further provided is an implementation manner, wherein the system further comprises a gas-water separator, a water storage tank and two preheaters, the gas-water separator is arranged between the fuel cell stack and the water storage tank and is used for separating gas and water in anode tail gas and cathode tail gas of the fuel cell stack;

[0010] the water storage tank is used for storing water separated in the gas-water separator;

[0011] the first preheater is arranged between the second storage tank and the gasifier, and the second preheater is arranged between the water storage tank and the gasifier, and is used for preheating the methanol aqueous solution in the second storage tank or the water in the water storage tank.

[0012] According to the aspect and any possible implementation manner thereof, further provided is an implementation manner, wherein the CO removal reactor is provided with two CO removal reactors and is connected in series.

[0013] According to the aspect and any possible implementation manner thereof, further provided is an implementation manner, wherein the gasifier is of a shell-and-tube structure, the tube layer comprises a plurality of branches and is connected with the first storage tank and the second storage tank respectively, the shell layer comprises an inlet pipeline and an outlet pipeline, the inlet pipeline is connected with an air pump or an air bottle, and the outlet pipeline is further connected with the first storage tank at the outlet of the gasifier, and the outlet pipeline is connected with the atmosphere or the first / second preheater.

[0014] According to the aspect and any possible implementation manner thereof, further provided is an implementation manner, wherein the reforming reactor is of a shell-and-tube structure, the tube layer and the shell layer both comprise an inlet pipeline and an outlet pipeline, a valve is arranged between the inlet pipeline of the tube layer and the inlet pipeline of the shell layer, the inlet pipeline of the shell layer is further connected with the methanol water vapor outlet pipeline of the gasifier, the outlet pipeline of the tube layer is connected with the atmosphere or the first / second preheater, and the outlet pipeline of the shell layer is branched into two pipelines through the valve, one of the two pipelines is connected with the CO removal reactor, and the other pipeline is connected with the atmosphere.

[0015] According to the aspect and any possible implementation manner thereof, further provided is an implementation manner, wherein the gas-water separator is provided with two gas-water separators, the fuel cell stack comprises a cathode and an anode and anode inlet and outlet pipelines and cathode inlet and outlet pipelines connected with the anode and the cathode respectively, the outlet pipeline of the anode is connected with the first gas-water separator, and the outlet pipeline of the cathode is connected with the second gas-water separator.

[0016] According to the aspect and any possible implementation manner thereof, further provided is an implementation manner, wherein the second preheater comprises a hot fluid flow channel and a cold fluid flow channel, the hot fluid flow channel is connected with the outlet pipeline of the shell layer of the gasifier and the outlet pipeline of the tube layer of the reforming reactor, and the cold fluid flow channel is connected with the cold fluid flow channel of the first preheater.

[0017] Aspects and any possible implementation modes mentioned above further provide an implementation mode, the first preheater comprises a hot fluid flow channel and a cold fluid flow channel, the hot fluid flow channel is connected with the CO removal reactor; and the cold fluid flow channel is connected with the second storage tank or the water storage tank.

[0018] The application further provides a methanol reforming hydrogen production method suitable for extreme environment, which is realized by using the system, and includes a cold start state and a stable operation state.

[0019] S1. air is introduced into the reforming reactor and the gasifier to perform chemical chain combustion and heat up to about 70 ℃;

[0020] S2. the methanol in the first storage tank and the second storage tank is gasified by chemical chain combustion in the gasifier, and the gasified methanol steam is partially catalytically combusted with air in the shell of the reforming reactor to realize rapid heating of the reforming reactor, and the other part of the methanol steam is catalytically combusted with air in the gasifier to gasify the methanol;

[0021] S3. when the shell of the reforming reactor is rapidly heated to a reforming reaction temperature, the introduction of air is stopped, and the methanol steam from the gasifier is introduced into the shell of the reforming reactor to perform a methanol steam reforming hydrogen production reaction;

[0022] S4. the reforming hydrogen gas generated by the reforming hydrogen production reaction enters two CO removal reactors connected in series in sequence, and then enters the anode of the fuel cell stack, while air is introduced into the cathode of the fuel cell stack, and electricity is generated by the electrochemical reaction of hydrogen and air in the stack.

[0023] Aspects and any possible implementation modes mentioned above further provide an implementation mode, wherein the stable operation state comprises: H1. the methanol aqueous solution in the second storage tank is preheated by the preheater, and then enters the shell of the reforming reactor to perform a reforming reaction after being gasified by the gasifier, to generate reforming hydrogen gas;

[0024] H2. the reforming hydrogen gas is cooled to below 70 ℃ by heat exchange with the methanol aqueous solution through the preheater after passing through the CO removal reactor, and then enters the anode of the fuel cell stack to perform discharge, while air is introduced into the cathode of the fuel cell stack, and electricity is generated by the electrochemical reaction of hydrogen and air in the stack.

[0025] Advantages of the application

[0026] This invention utilizes chemical loop combustion and catalytic combustion technologies involving air and methanol to heat the vaporizer, reforming reactor, and CO removal reactor to their respective operating temperatures. The methanol-water solution is vaporized in the vaporizer to form methanol steam, which then enters the reforming reactor for a methanol-water steam reforming reaction to generate reformed hydrogen. The reformed hydrogen then enters the CO removal reactor for CO removal. The CO-free reformed hydrogen enters the fuel cell stack for power generation. The anode exhaust gas from the stack then enters both the vaporizer and the reforming reactor to undergo catalytic combustion with air. The heat released from these reactions is used for the vaporization and reforming of the methanol-water solution. Compared to existing technologies, this invention offers the following advantages:

[0027] The present invention relates to a system whose cold start, liquid vaporization heating in the vaporizer, and hydrogen production heating in the reforming reactor all utilize heat provided by chemical looping combustion and catalytic combustion reactions. This reduces the dependence on electrical energy in the prior art, lowers system energy consumption, and improves the system's adaptability to complex environments.

[0028] This invention uses reformed hydrogen for power generation, which reduces the cost of hydrogen purification using methods such as palladium membranes and improves hydrogen yield and conversion efficiency. At the same time, by using reformed hydrogen to remove CO and introducing a small amount of air into the anode of the fuel cell stack, the impact of CO on the performance of the fuel cell stack is effectively reduced, enabling it to generate electricity stably. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of a system structure according to a preferred embodiment of the present invention, including a system cold start process and a methanol reforming hydrogen production and power generation process;

[0030] Figure 2 This is a schematic diagram of the system structure of another preferred embodiment of the present invention, showing the system cold start process.

[0031] Figure 3 The system structure diagram of another preferred embodiment of the present invention shows the methanol reforming hydrogen production power generation process.

[0032] Figure 1 1-2 are methanol storage tanks, 3 is methanol-water solution storage tank, 4 is pump, 5 is valve, 6 is vaporizer, 7 is reforming reactor, 8-9 are CO removal reactor, and 10 is fuel cell stack.

[0033] Figure 2 and Figure 3 1 is a methanol storage tank, 3 is a methanol-water solution storage tank, 4 is a pump, 6 is a vaporizer, 7 is a reforming reactor, 8 is a CO removal reactor, 10 is a fuel cell stack, 11-12 are gas-liquid separators, 13 is a water storage tank, and 14-15 are preheaters. Detailed Implementation

[0034] In order to better understand the technical solutions of the present application, the present application includes but is not limited to the specific embodiments described below, and similar techniques and methods should be considered as falling within the scope of the present application. In order to make the technical problems, technical solutions and advantages of the present application clearer, the following will be described in detail in conjunction with the drawings and specific embodiments.

[0035] It should be clear that the embodiments described in the present application are only a part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of the present application.

[0036] As shown in Figure 1 The present application provides a methanol reforming hydrogen power generation system, which comprises first storage tanks 1 and 2, both used for storing methanol, a second storage tank 3 used for storing methanol aqueous solution, a pump 4, a valve 5, a gasifier 6, a reforming reactor 7, CO removal reactors 8 and 9, a fuel cell stack 10, gas-water separators 11 and 12, a water storage tank 13, and preheaters 14 and 15, wherein:

[0037] The methanol storage tanks 1 and 2 are connected to the gasifier 6 by pipelines and used for storing methanol raw materials, which can be transported to the gasifier 6 for gasification under the drive of the pump 4 and the control of the valve 5;

[0038] The methanol aqueous solution storage tank 3 is connected to the gasifier 6 by a pipeline and used for storing methanol aqueous solution, which can be transported to the gasifier 6 for gasification under the drive of the pump 4;

[0039] The gasifier 6 is arranged between the storage tank 3 and the reforming reactor 7 and has a tube-shell structure, the tube layer is composed of several branches and connected to the storage tanks 2 and 3 to pass in methanol and methanol aqueous solution, the shell layer is connected to the storage tank 1 to pass in air and methanol, and fins are arranged inside for enhanced heat exchange; the shell layer is used for chemical reactions of air and methanol for chemical chain combustion and catalytic combustion, and the heat generated by the chemical reactions is used for the gasification of methanol and methanol aqueous solution in the tube layer;

[0040] The reforming reactor 7 is connected to the gasifier 6 and the CO removal reactor 8 and has a tube-shell structure, the tube layer passes in air and methanol and is used for chemical reactions of air and methanol for chemical chain combustion and catalytic combustion, which is an exothermic reaction; the shell layer passes in methanol steam from the gasifier 6 and is used for a hydrogen production reaction of methanol steam reforming, which is an endothermic reaction; at the same time, the exothermic reaction of the tube layer provides heat for the endothermic reaction of the shell layer, and the reforming hydrogen produced by the shell layer is sent to the CO removal reactor 8 and the CO removal reactor 9;

[0041] CO removal reactor 9, connected with fuel cell stack 10, is used for CO removal of the reformed hydrogen, which can be carried out by adsorption, CO preferential oxidation, CO selective methanation, and the reformed hydrogen after CO removal is used for fuel cell stack 10;

[0042] Fuel cell stack 10, connected with gas-water separator 11, is used for reformed hydrogen and air to generate electric energy through electrochemical reaction;

[0043] Gas-water separator 11, installed between fuel cell stack 10 and water storage tank 13, is used for separating gas and water in anode and cathode tail gas of fuel cell stack;

[0044] Water storage tank 13 is used for storing water separated from gas-water separator 11, and supplementing water for methanol steam reforming reaction;

[0045] Preheaters 14 and 15, installed between methanol water solution storage tank 3 or water storage tank 13 and gasifier 6, are used for preheating methanol water solution or water in water storage tank 13.

[0046] The shell layer of gasifier 6 is provided with inlet pipe and outlet pipe, the inlet pipe is connected with air pump or air bottle, air enters the shell layer of gasifier 6 to generate chemical chain combustion reaction and release heat, and the combustion tail gas after reaction is discharged to the atmosphere through the outlet pipe; when the temperature of gasifier 6 is increased to about 70℃, methanol in methanol storage tank 1 enters one of the branch pipes of the shell layer of gasifier 6, and is heated and gasified into methanol vapor by the heat released from the chemical chain combustion reaction; the methanol vapor includes two streams, one of which is merged into gasifier 6, and the other is merged into reforming reactor 7. Meanwhile, there is a branch pipe between the inlet pipe of gasifier 6 and air pump / air bottle, which is used to merge the above-mentioned methanol vapor, and the methanol vapor is mixed with air to enter the shell layer of gasifier 6 to generate catalytic combustion reaction and release heat, and the combustion tail gas after reaction is discharged to the atmosphere through the outlet pipe. When the temperature of gasifier 6 is further increased to about 110℃, methanol water solution in storage tank 3 enters one of the branch pipes of the shell layer of gasifier 6, and is heated and gasified into methanol water vapor by the heat released from the catalytic combustion reaction;

[0047] The shell layer of reforming reactor 7 is provided with inlet pipe and outlet pipe, the inlet pipe is connected with air pump or air bottle, air enters the shell layer of reforming reactor to generate chemical chain combustion reaction and release heat, and the combustion tail gas after reaction is discharged to the atmosphere through the outlet pipe. When the temperature of reforming reactor 7 is increased to about 70℃, there is a branch pipe between the inlet pipe of reforming reactor and air pump / air bottle, which is used to merge the methanol vapor from gasifier 6, and the methanol vapor is mixed with air to enter the shell layer of reforming reactor 7 to generate catalytic combustion reaction and release heat, and the combustion tail gas after reaction is discharged to the atmosphere through the outlet pipe.

[0048] The tube layer of the reforming reactor 7 is provided with an inlet pipe and an outlet pipe, and the inlet pipes of the shell layer and the tube layer are provided with valves for switching the control of the gas from the shell layer inlet pipe into the shell layer or from the tube layer inlet pipe into the tube layer. When the temperature of the reforming reactor 7 is further increased to 200-300°C due to the catalytic combustion reaction, the valves of the tube layer and the shell layer are switched to make the mixed gas of air and methanol vapor enter the tube layer of the reforming reactor and the catalytic combustion reaction occurs in the tube layer, and the combustion tail gas generated after the reaction is discharged into the atmosphere through the outlet pipe of the tube layer. The inlet pipe of the shell layer of the reforming reactor 7 is also connected to the methanol water vapor outlet pipe of the gasifier 6, and the inlet and outlet of the methanol water vapor are controlled by a valve; when the valves of the tube layer and the shell layer of the reforming reactor 7 are switched, the valve of the shell layer inlet pipe and the methanol water vapor outlet pipe of the gasifier 6 is opened to make the methanol water vapor enter the shell layer of the reforming reactor and perform the methanol water vapor reforming reaction to generate reforming hydrogen. The catalytic combustion reaction in the tube layer is an exothermic reaction, which provides heat for the endothermic reaction of the methanol water vapor reforming reaction in the shell layer.

[0049] The outlet pipe of the shell layer of the reforming reactor 7 has a branch pipe connected to the CO removal reactor 8, and the valve is switched to make the shell layer outlet pipe communicate with the atmosphere or the CO removal reactor.

[0050] The CO removal reactor 8 is a tube-shell structure, and the heat exchange is enhanced by adding fins and the like. When the methanol water vapor reforming reaction occurs in the shell layer of the reforming reactor 7, the valve of the shell layer outlet pipe of the reforming reactor 7 is switched to make the reforming hydrogen enter the shell layer of the CO removal reactor 8; the CO in the reforming hydrogen undergoes one or more of the adsorption, preferential oxidation, selective methanation and water-gas shift reactions in the shell layer of the CO removal reactor 8 to achieve CO removal of the reforming hydrogen. The shell layer outlet pipe of the CO removal reactor 8 is connected to the anode inlet pipe of the fuel cell stack 10, and the reforming hydrogen after CO removal enters the fuel cell stack through the anode inlet pipe.

[0051] The pipe layer of the CO removal reactor 8 is provided with inlet and outlet pipes. Since heat is generated during the CO removal process, heat exchange is required by fluid flow through the pipe layer. Heat exchange is achieved by the following methods: (1) air, cooling water, cooling liquid or other heat exchange medium is introduced into the inlet of the pipe layer to remove the heat generated during the CO removal process. The heat exchange medium is discharged into the atmosphere or is cooled and then introduced into the pipe layer of the CO removal reactor 8 again; (2) the CO removal reactor 8 is connected to the methanol storage tank 1 or 2 through the inlet pipe of the pipe layer, and the heat generated during the CO removal process is removed by the methanol. The outlet pipe of the pipe layer of the CO removal reactor is provided with a converging inlet at the connection pipe between the methanol storage tank 1 or 2 and the gasifier 6, and the converging inlet is controlled by a valve. The methanol after heat exchange enters the gasifier to be gasified into methanol vapor; (3) the CO removal reactor 8 is connected to the methanol aqueous solution storage tank 3 through the inlet pipe of the pipe layer, and the heat generated during the CO removal process is removed by the methanol aqueous solution. The outlet pipe of the pipe layer of the CO removal reactor is provided with a converging inlet at the connection pipe between the methanol aqueous solution storage tank and the gasifier, and the converging inlet is controlled by a valve. The methanol aqueous solution after heat exchange enters the gasifier to be gasified into methanol vapor; (4) the CO removal reactor 8 is connected to the water storage tank 13 through the inlet pipe of the pipe layer, and the heat generated during the CO removal process is removed by the water. The outlet pipe of the pipe layer of the CO removal reactor is provided with a converging inlet at the connection pipe between the water storage tank and the gasifier, and the converging inlet is controlled by a valve. The water after heat exchange enters the gasifier to be gasified into water vapor.

[0052] The fuel cell stack 10 includes a cathode and an anode, and the anode is connected to the anode inlet and outlet pipes, and the cathode is connected to the cathode inlet and outlet pipes. The outlet pipes of the anode and the cathode are connected to the first gas-water separator 12 and the second gas-water separator 11, respectively. The anode inlet pipe is connected to the CO-removed reforming hydrogen gas, and the cathode inlet pipe is connected to air. The reforming hydrogen gas and the air perform electrochemical reaction in the fuel cell stack 10 to generate electric energy. When the reforming hydrogen gas still contains a small amount of CO, 0-5% of air is mixed with the reforming hydrogen gas, and then the mixture enters the fuel cell stack.

[0053] The anode outlet pipe is connected to the inlet pipe of the first gas-water separator 12, the outlet of the first gas-water separator 12 is provided with a gas outlet pipe and a water outlet pipe, the water outlet pipe is connected to the water storage tank 13, the gas outlet pipe is provided with a first outlet pipe and a second outlet pipe, the first outlet pipe is connected to the shell inlet pipe of the gasifier 6, the second outlet pipe is connected to the inlet pipe of the tube layer of the reforming reactor 7, the first and second outlet pipes control the gas in and out through valves. When the fuel cell stack 10 is in a stable power generation state, the valves controlling the first and second outlet pipes are opened, and the valves of the methanol vapor pipes entering the shell of the gasifier 6 and the tube layer of the reforming reactor 7 are closed, so that the gas separated from the anode through the gas-water separator enters the shell of the gasifier and the tube layer of the reforming reactor, and catalytic combustion reaction occurs with the air entering the shell and the tube layer, thereby providing heat for the gasification of the methanol and the methanol vapor in the shell and the tube layer of the gasifier.

[0054] The cathode outlet pipe is connected to the inlet pipe of the second gas-water separator 11, the outlet of the second gas-water separator 11 is provided with a gas outlet pipe and a water outlet pipe, the water outlet pipe is connected to the water storage tank, and the gas outlet pipe is connected to the atmosphere. After the cathode outlet gas is separated through the gas-water separator, the water enters the water storage tank 13, and the gas is discharged to the atmosphere.

[0055] As an improvement of the present application, in order to further enhance the energy utilization efficiency of the methanol reforming hydrogen production system, a first preheater 14 and a second preheater 15 are additionally arranged between the methanol aqueous solution storage tank or the water storage tank and the gasifier, which are used for preheating the methanol aqueous solution or the water in the water storage tank, the first preheater 14 is close to the methanol aqueous solution storage tank 3 or the water storage tank 13, and the second preheater 15 is close to the gasifier 6. The first preheater 14 comprises a hot fluid flow channel and a cold fluid flow channel, the reforming hydrogen gas passing through the CO removal reactor 8 is introduced into the hot fluid flow channel, and then the reforming hydrogen gas is introduced into the anode of the fuel cell stack 10, and the cold fluid flow channel introduces the methanol aqueous solution or the water in the water storage tank, which is preheated for the first time through the hot fluid.

[0056] As an improvement of the present application, the second preheater 15 comprises a hot fluid flow channel and a cold fluid flow channel, the combustion tail gas from the shell outlet of the gasifier 6 and the combustion tail gas from the tube layer outlet of the reforming reactor 7 are introduced into the hot fluid flow channel, and then the combustion tail gas is discharged to the atmosphere, and the cold fluid flow channel introduces the methanol aqueous solution or the water from the first preheater 14, which is preheated for the second time through the hot fluid. Finally, the methanol aqueous solution or the water enters the gasifier for gasification.

[0057] The application heats the system by the way of air and methanol chemical looping combustion and catalytic combustion, and does not rely on external heat source and electric heating to start and maintain the reaction temperature, thereby reducing the system energy consumption. Moreover, the application relies on air and methanol to start and run the system, and only relies on a small amount of electric energy to control the system valve switch, signal acquisition and pump operation, thereby reducing the system complexity and making the system adapt to a more severe environment.

[0058] The CO concentration in the reforming hydrogen is reduced by removing CO from the reforming hydrogen, and the CO in the reforming hydrogen is reduced by introducing a small amount of air into the anode of the fuel cell stack.

[0059] The system realizes the self-maintenance temperature control of the gasification, reforming and CO removal reactor by integrating the chemical looping combustion, catalytic combustion and tail gas heat recovery cooperative heating strategy, and further strengthens the heat circulation by using the anode tail gas catalytic combustion, so that the system efficiency and environmental adaptability are improved without external assistance, and an innovative solution for reliable energy supply in extreme environment is provided.

[0060] As an embodiment of the application, the application further discloses a methanol reforming hydrogen production and power generation method suitable for extreme environment, and the method is realized by using the system, and includes a cold start state and a stable running state.

[0061] S1. air is introduced into the reforming reactor and the gasifier to heat by chemical looping combustion to 70 DEG C;

[0062] S2. the methanol in the first storage tank and the second storage tank is gasified by the heat release of the chemical looping combustion in the gasifier, and part of the gasified methanol steam is catalytically combusted with air in the shell of the reforming reactor to realize rapid heating of the reforming reactor, and the other part of the methanol steam is catalytically combusted with air in the gasifier to gasify the methanol;

[0063] S3. when the shell of the reforming reactor is rapidly heated to the reforming reaction temperature, the air introduction is stopped, and the methanol steam from the gasifier is introduced into the shell of the reforming reactor to perform the methanol steam reforming hydrogen production reaction;

[0064] S4. the reforming hydrogen produced by the reforming hydrogen production reaction enters two CO removal reactors connected in series in sequence, and then enters the anode of the fuel cell stack, and air is introduced into the cathode of the fuel cell stack, and electricity is generated by the electrochemical reaction of hydrogen and air in the stack.

[0065] Further, the stable running state includes: H1. the methanol aqueous solution in the second storage tank is preheated by the preheater, gasified by the gasifier and then enters the shell of the reforming reactor to perform the reforming reaction, and produces the reforming hydrogen;

[0066] H2. After passing through the CO removal reactor, the reformed hydrogen is cooled to below 70°C by exchanging heat with a methanol-water solution in a preheater. It then enters the anode of the fuel cell stack for discharge, while air is introduced into the cathode of the fuel cell stack. Electricity is generated through the electrochemical reaction of hydrogen and air within the stack.

[0067] Specifically, such as Figure 1 As shown in the illustration, this invention provides a power generation process for a methanol reforming hydrogen production system suitable for extreme environments. The process includes cold start and steady state. During the steady state, the vaporization of methanol and methanol-water solution in the vaporizer and the reforming reaction in the reforming reactor provide heat, still using the air and methanol catalytic combustion mentioned in the cold start process. The system directly enters the steady state after the cold start, including the following steps: First, air is introduced into the reforming reactor 7 and the vaporizer 6 to raise the temperature to approximately 70°C through chemical looping combustion. The heat released from chemical looping combustion in the vaporizer 6 is used for the vaporization of methanol in methanol storage tanks 1 and 2. Part of the vaporized methanol vapor undergoes catalytic combustion with air within the shell of the reforming reactor 7, rapidly raising the temperature of the reforming reactor. The other part of the methanol vapor undergoes catalytic combustion with air within the vaporizer 6 for methanol vaporization. When the shell of reforming reactor 7 is rapidly heated to the reforming reaction temperature, air supply is stopped, and methanol-water vapor is introduced into the shell of reforming reactor 7. This methanol-water vapor is generated by vaporizing an aqueous methanol solution in storage tank 3 via vaporizer 6. The methanol-water vapor then undergoes a methanol-water vapor reforming reaction to produce hydrogen within the shell of reforming reactor 7. Simultaneously, methanol vapor is introduced into the tube layer of reforming reactor 7 for catalytic combustion with air to heat the methanol-water vapor reforming reaction within the shell of reforming reactor 7. The reformed hydrogen produced by the methanol-water vapor reforming reaction enters CO removal reactors 8 and 9, and then enters the anode of fuel cell stack 10. Air is simultaneously introduced into the cathode of fuel cell stack 10, and electricity is generated through the electrochemical reaction of hydrogen and air within stack 10. Since the reformed hydrogen after CO removal still contains a small amount of CO, a small amount of air needs to be mixed into the reformed hydrogen introduced into fuel cell stack 10 to reduce CO poisoning of the stack.

[0068] In the above power generation process, a single CO removal reactor may be used, or... Figure 1 As shown, CO is removed from reformed hydrogen by connecting two or more CO removal reactors in series.

[0069] The present invention also provides another embodiment, such as Figure 2 and Figure 3 As shown, Figure 2 The gray lines in Figure 3 indicate that the cold start process does not involve the path shown by the gray lines. The specific power generation process includes a cold start state and a steady state, where the cold start state is as follows: Figure 2As shown, specifically including: in the low temperature environment of-50℃, the freezing point of methanol solution and methanol aqueous solution is-97.8℃ and-70℃ respectively, and no solution icing. In the cold start operating condition, first, air is introduced into the reforming reactor 7 and the gasifier 6 for chemical chain combustion, so that the reforming reactor 7 and the gasifier 6 are heated from the low temperature environment (-50℃ to room temperature) to about 70℃. The heat released by the chemical chain combustion in the gasifier 6 is used for the gasification of the methanol in the storage tank 1, and part of the gasified methanol steam is catalytically combusted with air in the shell of the reforming reactor 7 to realize rapid heating of the reforming reactor, and the other part of the methanol steam is catalytically combusted with air in the gasifier 6 to gasify the methanol. When the shell of the reforming reactor 7 is rapidly heated to the reforming reaction temperature (about 250℃), the introduction of air is stopped, and the methanol steam generated by the gasification is introduced into the shell of the reforming reactor 7, wherein the methanol steam is generated by the gasification of the methanol aqueous solution in the storage tank 3 through the gasifier 6, and then the methanol steam is subjected to steam reforming reaction in the shell of the reforming reactor 7 to obtain reforming hydrogen. At this time, the methanol steam and air are introduced into the tube layer of the reforming reactor 7 to perform catalytic combustion to provide heat for the reforming reaction in the shell of the reforming reactor 7, and the catalytic combustion reaction tail gas is used to preheat the methanol aqueous solution through the preheater 15. During the cold start process, the reaction tail gas at about 250℃ in the shell of the reforming reactor 7 passes through the CO removal reactor 8, realizing the synchronous cold start of the CO removal reactor.

[0070] Before the system is stable, the reforming hydrogen passes through the CO deep removal reactor 8 and is introduced into the gasifier 6, and is mixed with air to occur catalytic combustion reaction, and the heat released by the reaction is used for the gasification of the methanol aqueous solution. After the system is in stable state, the reforming hydrogen is introduced into the fuel cell stack 10, and part of the anode tail gas of the stack 10 is used for catalytic combustion in the tube layer of the reforming reactor to replace the methanol steam to provide heat for the reforming reaction; and the other part is used for catalytic combustion in the gasifier to replace the methanol steam to provide heat for the gasification of the methanol solution or the methanol and water.

[0071] As Figure 3The shown is a steady state operation, the steady state process of the gasifier of the methanol and methanol aqueous solution and the reforming reactor of the reforming reaction heating, no longer using the air and methanol catalytic combustion heating mentioned in the cold start process, but using the anode tail gas of the fuel cell stack and the catalytic combustion of the air heating. Specifically, in the steady state operation stage, the methanol aqueous solution in the storage tank 3 (when the methanol aqueous solution is almost consumed, the valve is opened, the water in the water storage tank 13 and the methanol solution in the storage tank 1 are used) is heated through the preheaters 14 and 15, and then enters the shell of the reforming reactor 7 after being gasified in the gasifier 6 to occur the reforming reaction to produce the reforming hydrogen. The produced reforming hydrogen passes through the CO removal reactor 8, and then is cooled to below 70 DEG C through the preheater and the methanol aqueous solution (or water) heat exchange, and then enters the anode of the fuel cell stack 10 to discharge, while the air is introduced into the cathode of the fuel cell stack 10 to generate electricity through the electrochemical reaction of the hydrogen and the air in the stack 10. Since the reforming hydrogen after the CO removal still contains a small amount of CO, a small amount of air needs to be mixed into the reforming hydrogen introduced into the fuel cell stack 10 to reduce the CO poisoning of the stack. The anode tail gas and the cathode tail gas of the stack 10 are separated from the water through the gas-liquid separator, and the separated water enters the water storage tank 13 for standby, and the anode tail gas (containing a small amount of hydrogen) after the gas-liquid separation enters the gasifier 6 and the reforming reactor 7 to perform the catalytic combustion reaction with the air to heat the methanol aqueous solution gasification in the gasifier 6 and the reforming reaction in the reforming reactor 7.

[0072] In the above process, two CO removal reactors 8 and 9 in series are used, and the reactions involved in the reactors are exothermic reactions. In order to maintain the temperature stability of the reactors 8 and 9, the methanol solution in the storage tank 1 and the methanol aqueous solution in the storage tank 3 need to enter the CO removal reactors 8 and 9 respectively to perform the heat exchange to maintain the temperature stability of the reactors 8 and 9.

[0073] The terms used in the embodiments of the present application are merely for the purpose of describing the specific embodiments, and are not intended to limit the present application. The singular forms "a", "an" and "the" used in the embodiments of the present application and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise.

[0074] The above description shows and describes several preferred embodiments of the present application, but as mentioned before, it should be understood that the present application is not limited to the forms disclosed herein, and should not be considered as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the application conceived herein, by the above teaching or related technical or knowledge. The modifications and changes made by the person skilled in the art without departing from the spirit and scope of the present application shall be within the protection scope of the appended claims of the present application.

Claims

1. A methanol reforming hydrogen generation system suitable for extreme environments, characterized in that, The system comprises a first storage tank, a second storage tank, a gasifier, a reforming reactor, a CO removal reactor and a fuel cell stack, wherein the first storage tank stores methanol and the second storage tank stores methanol aqueous solution, and the first storage tank and the second storage tank are connected to the gasifier and the reforming reactor simultaneously for providing methanol and methanol aqueous solution respectively; The gasifier and the reforming reactor are connected, and air and methanol undergo chemical reactions of chemical chain combustion and catalytic combustion in the gasifier, and the heat generated by the chemical reactions is used for gasification of the methanol and the methanol aqueous solution; The reforming reactor is connected to the CO removal reactor, and air and methanol undergo chemical reactions of chemical chain combustion and catalytic combustion in the reforming reactor, and the heat generated by the chemical reactions is used for providing heat for a methanol steam reforming process for hydrogen production; The CO removal reactor is connected to the fuel cell stack, and is used for removing CO in the reforming hydrogen, and the reforming hydrogen after removal of CO is input to the fuel cell stack; The fuel cell stack uses the received reforming hydrogen to generate electricity.

2. The power generation system of claim 1, wherein, The system further comprises a gas-water separator, a water storage tank and two preheaters, the gas-water separator is arranged between the fuel cell stack and the water storage tank, and is used for separating gas and water in anode tail gas and cathode tail gas of the fuel cell stack; The water storage tank is used for storing water separated in the gas-water separator; The first preheater is arranged between the second storage tank and the gasifier, and the second preheater is arranged between the water storage tank and the gasifier, and is used for preheating the methanol aqueous solution in the second storage tank or the water in the water storage tank respectively.

3. The power generation system of claim 2, wherein, The CO removal reactor is provided with two and is connected in series.

4. The power generation system of claim 1, wherein, The gasifier is of a shell-and-tube structure, the tube layer comprises a plurality of branches connected to the first storage tank and the second storage tank respectively, the shell layer comprises an inlet pipe and an outlet pipe, the inlet pipe is connected to an air pump or an air bottle, and the outlet pipe is further connected to the first storage tank at an outlet of the gasifier, and the outlet pipe is connected to the atmosphere or connected to the first / second preheater.

5. The power generation system of claim 3, wherein, The reforming reactor is of a shell-and-tube structure, the tube layer and the shell layer both comprise an inlet pipe and an outlet pipe, a valve is arranged between the inlet pipe of the tube layer and the inlet pipe of the shell layer, the inlet pipe of the shell layer is further connected to a methanol steam outlet pipe of the gasifier, the outlet pipe of the tube layer is connected to the atmosphere or connected to the first / second preheater, and the outlet pipe of the shell layer is branched into two pipes by the valve, one of the two pipes is connected to the CO removal reactor, and the other pipe is connected to the atmosphere.

6. The power generation system of claim 2, wherein, The gas-water separator is provided with two, the fuel cell stack comprises a cathode and an anode, and anode inlet and outlet pipes and cathode inlet and outlet pipes connected to the anode and the cathode respectively, the outlet pipe of the anode is connected to the first gas-water separator, and the outlet pipe of the cathode is connected to the second gas-water separator.

7. The power generation system of claim 2, wherein, The second preheater comprises a hot fluid flow channel and a cold fluid flow channel, the hot fluid flow channel is connected to the outlet pipe of the shell layer of the gasifier and the outlet pipe of the tube layer of the reforming reactor, and the cold fluid flow channel is connected to the cold fluid flow channel of the first preheater.

8. The power generation system of claim 2, wherein, The first preheater comprises a hot fluid flow channel and a cold fluid flow channel, the hot fluid flow channel is connected to the CO removal reactor, and the cold fluid flow channel is connected to the second storage tank or the water storage tank.

9. A method of methanol reforming for hydrogen production for power generation suitable for extreme environments, characterized by, The method is implemented by using the system according to any one of claims 1-8, including a cold start state and a stable operation state, wherein the cold start state includes the following steps: S1. air is introduced into the reforming reactor and the gasifier to heat up to about 70 DEG C by chemical looping combustion; S2. the methanol in the first and second storage tanks is gasified by chemical looping combustion in the gasifier, and the gasified methanol steam is partially catalytically combusted with air in the shell of the reforming reactor to rapidly heat up the reforming reactor, and the other part of the methanol steam is catalytically combusted with air in the gasifier to gasify the methanol; S3. when the shell of the reforming reactor is rapidly heated up to the reforming reaction temperature, the introduction of air is stopped, and the methanol steam from the gasifier is introduced into the shell of the reforming reactor to perform the methanol steam reforming reaction for hydrogen production; S4. the reforming hydrogen gas generated by the reforming reaction enters two CO removal reactors connected in series, and then enters the anode of the fuel cell stack, while air is introduced into the cathode of the fuel cell stack, and electricity is generated by the electrochemical reaction of hydrogen and air in the stack.

10. The method of claim 9, wherein, The stable operation state includes: H1. the methanol aqueous solution in the second storage tank is preheated by the preheater, gasified by the gasifier, and then enters the shell of the reforming reactor to perform the reforming reaction to generate reforming hydrogen gas; H2. the reforming hydrogen gas passes through the CO removal reactor, is cooled to below 70 DEG C by heat exchange with the methanol aqueous solution by the preheater, and then enters the anode of the fuel cell stack to discharge, while air is introduced into the cathode of the fuel cell stack, and electricity is generated by the electrochemical reaction of hydrogen and air in the stack.

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