Fuel reforming system

Abstract

The utility model provides a fuel reforming system. The fuel reforming system comprises a reformer body and a combustor, a fuel gasification area, a reforming area, a heating area, a water vapor migration balance area and a methanation area are arranged in the reformer body. Compared with the prior art, the fuel reforming system provided by the utility model adopts an explosion combustion technology, the starting time of the system is shortened, the reaction temperature of the system can be effectively controlled by changing the amount of organic fuel, the application temperature range is from 200 DEG C to 1000 DEG C, and the fuel reforming system can be suitable for a multi-purpose reaction system.

Description

Technical Field

[0001] The utility model belongs to the technical field of fuel cells, and in particular relates to a fuel reforming system. Background Art

[0002] Polymer Electrolyte Membrane or Proton Exchange Membrane Fuel Cell (PEMFC) has been developed towards distributed fixed power generation, portable power generation, or electric vehicle power systems in industrial applications. Fixed fuel cell power generation systems or backup power systems are the earliest markets for fuel cells, and both application systems require a fuel reformer hydrogen production unit, and the above applications emphasize high efficiency, low parasitic power, high hydrogen concentration, and preferably take into account fast response and short start-up time.

[0003] The fuel reformer can convert hydrocarbon fuel into hydrogen-rich reformate with a carbon monoxide (CO) concentration below 20 ppm to supply the fuel required by the PEMFC power generation system. Generally speaking, the fuel reformer system includes reforming reaction for converting fuel into synthesis gas, water gas-shift (WGS), selective oxidation reaction (Preferential oxidation, PrOX) or methanation reaction, and anode waste hydrogen oxidation reaction. The existing fuel reformer hydrogen production units are almost all designed with steam reforming reaction (SR) or autothermal reforming reaction (ATR). The former has the advantage of high hydrogen concentration, but it also has the disadvantages of long start-up time and slow response rate. The main development units include Tokyo Gas Company and Toshiba Corporation of Japan. The latter has the advantages of short start-up time and fast response, but it also has the disadvantages of low hydrogen concentration and large parasitic power due to the need to inject a large amount of air during the reaction. The main development units include Johnson Matthey Company of the United Kingdom. The existing fuel reformer system designed for autothermal reforming reaction is that the catalyst at the front end of the reforming reactor first induces the hydrocarbons to undergo an exothermic partial oxidation reaction with oxygen, and the catalyst at the rear end of the reforming reactor undergoes a steam reforming reaction through the high temperature generated by the front end partial reaction. The feeds participating in the reforming reaction, such as natural gas, water and air, are preheated and vaporized and simultaneously injected into the same reforming catalyst device. Therefore, the proportion of the steam reforming reaction of hydrocarbons catalyzed by the rear end catalyst is completely subject to the oxygen / hydrocarbon molar ratio (O2 / C molar ratio) of the front end partial oxidation reaction, and the hydrogen concentration in the reformed gas is mostly around 50%. The existing fuel reformer system designed for steam reforming reaction must first be indirectly heated to put the steam reforming catalyst in a state where it can start catalyzing the steam reforming reaction, and then the fuel feed (fuel supply) participating in the reforming reaction, such as natural gas and water, is introduced, so the startup time is very lengthy. Utility Model Content

[0004] In view of this, the technical problem to be solved by the present invention is to provide a fuel reforming system, which has a fast start-up time, diversified fuels and obtains hydrogen with high purity.

[0005] The utility model provides a fuel reforming system, comprising a reformer body and a burner; the reformer body is provided with a fuel gasification region, a reforming region, a heating region, a water vapor migration balance region and a methanation region; the fuel gasification region, the reforming region, the water vapor migration balance region and the methanation region are connected in sequence; the heating region is not connected with the fuel gasification region, the reforming region, the water vapor migration balance region and the methanation region;

[0006] The reformer body is provided with a reforming fuel inlet; the reforming fuel inlet is connected to the fuel gasification area; the outside of the reforming area is surrounded by a heating area;

[0007] The burner comprises a fuel distribution device and a spark plug; the fuel distribution device is provided with a flame hole; the fuel distribution device is connected with a heating area through the flame hole; and the spark plug extends into the heating area.

[0008] Preferably, the burner further comprises an organic fuel storage device and a diffraction pump; the organic fuel storage device is connected to the fuel distribution device via the diffraction pump.

[0009] Preferably, the organic fuel storage device comprises a pressure-resistant shell, a fuel bag, a fuel outlet and an air filling port; the fuel bag is arranged in the cavity of the pressure-resistant shell and is connected to the fuel outlet; the air filling port is connected to the cavity of the pressure-resistant shell and is not connected to the fuel bag.

[0010] Preferably, the volume of the fuel bag is 1 / 3 to 2 / 3 of the volume of the cavity of the pressure-resistant shell;

[0011] The pressure in the cavity of the pressure-resistant shell is 4-6 bar.

[0012] Preferably, the fuel outlet is provided with a solenoid valve, and the opening and closing of the fuel outlet is controlled by the solenoid valve.

[0013] Preferably, the reformer body further includes a waste heat utilization area and an exhaust gas outlet; the fuel gasification area is arranged in the waste heat utilization area, and the two are not connected; the heating area is connected to the exhaust gas outlet through the waste heat utilization area.

[0014] Preferably, the reformer body is barrel-shaped;

[0015] The spark plug is 0.5 to 1 cm higher than the flame hole.

[0016] Preferably, the fuel gasification region, reforming region and heating region are located in the center of the reformer body; the water vapor migration balance region and the methanation region are annularly wrapped around the fuel gasification region, reforming region and heating region.

[0017] Preferably, the heating area is annularly wrapped around the reforming area; the reforming area is connected to the water vapor migration balance area through a pipeline.

[0018] Preferably, the reforming region is filled with a reforming hydrogen production catalyst; the reforming hydrogen production catalyst comprises copper oxide and zinc oxide;

[0019] The water vapor migration equilibrium region is filled with a water vapor migration reaction catalyst;

[0020] The methanation zone is filled with a noble metal catalyst and / or a nickel-based catalyst.

[0021] The utility model provides a fuel reforming system, including a reformer body and a burner; the reformer body is provided with a fuel gasification area, a reforming area, a heating area, a water vapor migration balance area and a methanation area; the fuel gasification area, the reforming area, the water vapor migration balance area and the methanation area are connected in sequence; the heating area is not connected with the fuel gasification area, the reforming area, the water vapor migration balance area and the methanation area; the reformer body is provided with a reforming fuel inlet; the reforming fuel inlet is connected with the fuel gasification area; the outside of the reforming area is surrounded by a heating area; the burner includes a fuel distribution device and a spark plug; the fuel distribution device is provided with a flame hole; the fuel distribution device is connected with the heating area through the flame hole; the spark plug extends into the heating area. Compared with the prior art, the fuel reforming system provided by the utility model adopts explosive combustion technology to shorten the system startup time, and can also effectively control the system reaction temperature by changing the amount of organic fuel. The application temperature range is from 200°C to 1000°C, which can be applied to multi-purpose reaction systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A schematic diagram of the structure of the fuel reforming system provided by the utility model;

[0023] Figure 2 A schematic diagram of the structure of the burner provided by the utility model;

[0024] Figure 3 This is a structural schematic diagram of the organic fuel storage device provided by the utility model. DETAILED DESCRIPTION

[0025] The following will be combined with the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0026] The utility model provides a fuel reforming system, including a reformer body and a burner; a fuel gasification area, a reforming area, a heating area, a water vapor migration balance area and a methanation area are arranged in the reformer body; the fuel gasification area, the reforming area, the water vapor migration balance area and the methanation area are connected in sequence; the heating area is not connected with the fuel gasification area, the reforming area, the water vapor migration balance area and the methanation area; the reformer body is provided with a reforming fuel inlet; the reforming fuel inlet is connected with the fuel gasification area; the outside of the reforming area is surrounded by a heating area; the burner includes a fuel distribution device and a spark plug; the fuel distribution device is provided with a flame hole; the fuel distribution device is connected with the heating area through the flame hole; the spark plug extends into the heating area; the temperature is rapidly increased by explosive combustion, so that the start-up time of the reformer is less than 3 minutes and the fastest is 5 seconds.

[0027] See also Figure 1 , Figure 1 This is a schematic diagram of the structure of the fuel reforming system provided by the utility model, wherein 1 is a reforming fuel inlet, 2 is a fuel gasification area, 3 is a reforming area, 4 is a heating area, 5 is a water vapor migration balance area, 6 is a methanation area, 7 is a waste heat utilization area, 8 is an exhaust gas outlet, 9 is a reformed product outlet, 10 is a burner, 11 is an organic fuel storage device, and 12 is an air inlet.

[0028] In a specific embodiment provided by the utility model, the reformer body further includes a waste heat utilization area and an exhaust gas outlet; the fuel gasification area is arranged in the waste heat utilization area, and the two are not connected; the heating area is connected to the exhaust gas outlet through the waste heat utilization area; and the exhaust gas generated by the combustion of the heating area is discharged through the exhaust gas outlet. The utility model can utilize the heat of the waste heat utilization area to gasify the reforming fuel without using it for heating, thereby improving the thermal efficiency.

[0029] In a specific embodiment provided by the present invention, the reformer body is preferably barrel-shaped; specifically, the fuel gasification region, reforming region and heating region are located in the center of the reformer body to form an inner barrel; the water vapor migration balance region and the methanation region are annularly wrapped around the fuel gasification region, reforming region and heating region, that is, the water vapor migration balance region and the methanation region form an outer barrel; the height ratio of the water vapor migration balance region to the methanation region is preferably 1:1; during operation, the temperature changes gradually from the bottom to the top (that is, from the burner part to the top reforming fuel inlet); for example, the natural gas reforming temperature changes from 1000 o C (burner part) to top 200 o C, and the outer barrel temperature rises from 500 o C to top 200 oC, this temperature range includes the water vapor equilibrium (CO reacts with water vapor to produce carbon dioxide and hydrogen) temperature (350 o C) Step down to the middle 250 o C water vapor equilibrium temperature, progressing to 200 o C. From 250 o C to 200 o C for catalytic methanation reaction to reduce the CO content to below 3ppm, so that it can be applied to proton exchange membrane fuel cells. The thickness of the water vapor migration equilibrium region and the methanation region along the barrel center direction for reformers below 10 kW is preferably the same as the radius of the inner barrel; so as to achieve effective thermal management; when the reformer above 10 kW is adjusted to more than half of the inner barrel radius, its temperature is adjusted by the outer insulation material. Relatively speaking, the methanol reforming temperature is from 350 o C (burner part) to top 100 o C, and the outer barrel temperature rises from 300 o C to Top 100 o C, this temperature range includes the water vapor equilibrium (CO reacts with water vapor to produce carbon dioxide and hydrogen) temperature (300 o C) Step down to the middle 250 o C water vapor equilibrium temperature, progressing to 100 o C. From 250 o C to 100 o C catalyzes methanation reaction to reduce CO content to below 3ppm, so that it can be applied to proton exchange membrane fuel cells. The reformer body is a barrel design, which can effectively and reasonably utilize heat, reduce waste heat removal, and improve efficiency.

[0030] In a specific implementation manner provided by the present invention, the heating area is annularly wrapped around the reforming area; the reforming area is connected to the water vapor migration balance area through a pipeline.

[0031] In a specific embodiment provided by the present invention, the fuel gasification zone is located above the reforming zone; further specifically, the reformer body also includes a waste heat utilization zone, the waste heat utilization zone is arranged above the reforming zone and the heating zone, and the waste heat utilization zone is connected to the heating zone; the fuel gasification zone is arranged in the waste heat utilization zone; the water vapor migration balance zone and the methanation zone are annularly wrapped around the waste heat utilization zone, the reforming zone and the heating zone.

[0032] In a specific embodiment provided by the utility model, the reforming region is filled with a reforming hydrogen production catalyst; the fuel to be reformed, such as methanol, ethanol, methane, or biomass oil, enters the reformer body through the reforming fuel inlet together with water, and enters the reforming region after being gasified in the fuel gasification region. The reforming region is in a high-temperature heating zone, and its temperature can be changed according to different fuels, such as the methanol reforming temperature at 300°C, the ethanol reforming temperature at 650°C, and the methane reforming temperature at 850°C~1000°C. The reforming hydrogen production catalyst includes copper oxide and zinc oxide; according to different situations, Rh can also be added to reduce carbon deposition; in addition, most of the research on steam reforming reforming reactions is based on the application of CuO / ZnO and CuO / ZnO / Al2O3 catalysts; aluminum oxide is added to the catalyst to improve its surface area and mechanical strength and prevent catalyst sintering; zinc oxide can improve the dispersibility of Cu and the reducibility of CuO. Specifically, the reforming hydrogen production catalyst may be Cu, ZnO and Al2O3 in a mass ratio of 50:40:10, with a conversion rate of 88.7% and a CO formation selectivity of 0.5%. In addition, the particle size and distribution of the catalyst are related to the design, and the retention time of the reforming fuel gas can be adjusted by the loading and assembly of the reforming hydrogen production catalyst to optimize the purity of the hydrogen at the outlet.

[0033] In a specific embodiment provided by the utility model, the water vapor migration equilibrium region is filled with a water vapor migration reaction catalyst; the methanation region is filled with a noble metal catalyst and / or a nickel-based catalyst; the high-pressure gas from the reforming region undergoes a water vapor migration reaction in the water vapor migration equilibrium region to reduce the content of CO, and at the same time removes a trace amount of CO through methanation, so that hydrogen can be used for proton exchange membrane fuel cells. Iron chromium (Fe-Cr) and copper zinc (Cu-Zn) catalysts are used to promote water vapor migration reactions at high and low temperatures, respectively. The water vapor migration reaction is carried out at 250°C to 300°C, and Cu and Ni, Ce (La) Ox, Rh / CeO2 / Al2O3, etc. are also used. The catalyst filled in the methanation region can be a noble metal catalyst or a nickel-based catalyst, and the preferred nickel-based catalyst is dispersed on an oxide support, such as a Ni nanoparticle catalyst supported by Al2O3, SiO2, and TiO2. Since the temperature of the water vapor migration equilibrium zone and the methanation zone is different, the position of the heating zone controls the distribution of water vapor migration and methanation zones. In the present invention, the water vapor migration equilibrium zone is preferably located below the methanation zone, that is, the water vapor migration equilibrium zone is closer to the heating zone than the methanation zone. The present invention effectively combines the distribution of the catalyst and the distribution of the temperature to achieve the best purity of the hydrogen.

[0034] The fuel reforming system provided by the utility model includes a burner, which provides heat for the reformer body, so that the reforming fuel reacts with water vapor at high temperature to generate hydrogen, carbon dioxide and other by-products. The heating speed directly affects the start-up time of the entire system.

[0035] In a specific embodiment provided by the present invention, the burner is preferably located below the reformer body; the burner includes a fuel distribution device and a spark plug, see Figure 2 , Figure 2 The schematic diagram of the structure of the burner is shown in Figure 13, in which 13 is a fuel distribution device, 14 is a flame hole, and 15 is a spark plug; the fuel distribution device includes an organic fuel inlet and an air inlet; the organic fuel and air are mixed in the fuel distribution device; the fuel distribution device is provided with a flame hole; the fuel distribution device is preferably annular; the flame holes are preferably evenly distributed on the annular fuel distribution device; the fuel distribution device is connected to the heating area through the flame hole; the spark plug is preferably arranged in the middle of the annular fuel distribution device, and more preferably arranged in the center area of ​​the annular ring; the spark plug extends into the heating area; the spark plug is preferably 0.5 to 1 cm higher than the flame hole, and this area is a fuel-rich area, which produces explosive combustion to increase the temperature rapidly, so that the start-up time of the reformer is less than 3 minutes and can reach 5 seconds at the fastest. The organic fuel and air enter the fuel distribution device in proportion and are ignited by the spark plug, and the flame hole burns the fuel.

[0036] In a specific embodiment provided by the present utility model, the burner preferably further includes an organic fuel storage device and a diffraction pump; the organic fuel storage device is connected to the fuel distribution device through the diffraction pump.

[0037] In a specific embodiment provided by the present invention, the organic fuel storage device comprises a pressure-resistant shell, a fuel bag, a fuel outlet and an air filling port, see Figure 3 , Figure 3It is a schematic diagram of the structure of an organic fuel storage device, wherein 16 is a pressure-resistant shell, 17 is a fuel bag, 18 is a fuel outlet, and 19 is an air filling port; the fuel bag is arranged in the cavity of the pressure-resistant shell and is connected to the fuel outlet; the fuel bag is used to store organic fuel. Since the instantaneous temperature rise of the fuel reforming system depends on the composition of the fuel, the selection of organic fuel is based on the convenience of carrying and high calorific value of the fuel, which is conducive to explosive temperature rise. Table 1 lists commonly used fuels. MAPP fuel is commonly used in nail guns and other construction tools. Denatured MAPP fuel is a mixture or isomer of butane and butene. Other liquid fuels can also be used, and the fuel is selected according to the gasification of the fuel and the composition of the explosive combustion. This explosive combustion is only a small part, and its sound is relatively small, and it is inside the reformer, so the noise is controllable. The utility model adopts tool fuel available on the market as the ignition organic fuel. The amount used for each ignition is in the range of several milliliters. The volume of the fuel bag is preferably 1 / 3 to 2 / 3 of the volume of the cavity of the pressure-resistant shell, and more preferably 1 / 2; the inflation port is connected to the cavity of the pressure-resistant shell and is not connected to the fuel bag, and air is filled in through the inflation port to make the cavity of the pressure-resistant shell have pressure, and the pressure in the cavity of the pressure-resistant shell is preferably 4 to 6 bar, more preferably 5 to 6 bar, and more preferably 6 bar; the fuel bag is connected to the fuel distribution device through the fuel outlet and the diffraction pump in turn, and preferably, the fuel outlet is provided with a solenoid valve, and the switch of the fuel outlet is controlled by the solenoid valve, and the flow rate and flow rate of the fuel can be set as required. When the solenoid valve is opened, the fuel can be sprayed out, and the time when the solenoid valve is opened controls the amount of fuel, which is the fuel usually required for ignition and causes the temperature of the reaction chamber to rise sharply. The outlet of the solenoid valve enters the burner through the diffraction pump. This design can eliminate the life and control problems caused by the pump.

[0038] Table 1 Combustion temperature of common fuels

[0039]

[0040] The gas, air and oxygen temperatures in Table 1 are 20°C. Stoichiometric combustion - no excess air / oxygen; MAPP gas is a mixture of various hydrocarbons, primarily methylacetylene and propadiene.

[0041] In summary, the fuel reforming system provided by the utility model has the following advantages:

[0042] 1) Start-up time: Generally, the start-up time of the reformer is more than 30 minutes to obtain high-purity hydrogen. The main problem is that the temperature of the reformer rises slowly. The utility model adopts explosive combustion and combines optimized water vapor migration and methanogenic CO removal control to effectively control the reaction temperature. The temperature of the reactor is changed by changing the amount of organic fuel.

[0043] 2) Fuel diversification: Fuel reformers are divided into methane steam reforming, methanol steam reforming, ethanol steam reforming, biomass steam reforming, etc. The fuel reforming system provided by the utility model is a multi-purpose form of a reactor, which can be used in a temperature range from 200°C to 1000°C. The reaction temperature is effectively controlled by adjusting the amount of ignition organic fuel. Different fuels can have different amounts of ignition organic fuel and different reaction temperatures.

[0044] 3) Hydrogen purity: The purity of hydrogen mainly depends on the catalytic high and low temperature water vapor migration balance and methanation to remove CO. The anode tail gas of the fuel cell is returned to the reformer for combustion after water vapor separation. If ammonia is used as the raw material, the methanation and water vapor transfer parts become the residual ammonia adsorption system to ensure the purity of the hydrogen.

[0045] 4) Compact design and waste heat utilization: This reformer is a barrel design that effectively and reasonably utilizes heat, releasing less waste heat and achieving high thermal efficiency.

[0046] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A fuel reforming system, characterized in that: It comprises a reformer body and a burner; the reformer body is provided with a fuel gasification region, a reforming region, a heating region, a water vapor migration balance region and a methanation region; the fuel gasification region, the reforming region, the water vapor migration balance region and the methanation region are connected in sequence; the heating region is not connected with the fuel gasification region, the reforming region, the water vapor migration balance region and the methanation region; The reformer body is provided with a reforming fuel inlet; the reforming fuel inlet is connected to the fuel gasification area; the outside of the reforming area is surrounded by a heating area; The burner comprises a fuel distribution device and a spark plug; the fuel distribution device is provided with a flame hole; the fuel distribution device is connected with a heating area through the flame hole; and the spark plug extends into the heating area.

2. The fuel reforming system according to claim 1, characterized in that: The burner also includes an organic fuel storage device and a diffraction pump; the organic fuel storage device is connected to the fuel distribution device through the diffraction pump.

3. The fuel reforming system according to claim 2, characterized in that: The organic fuel storage device comprises a pressure-resistant shell, a fuel bag, a fuel outlet and an air filling port; the fuel bag is arranged in the cavity of the pressure-resistant shell and is connected with the fuel outlet; the air filling port is connected with the cavity of the pressure-resistant shell and is not connected with the fuel bag.

4. The fuel reforming system according to claim 3, characterized in that: The volume of the fuel bag is 1 / 3 to 2 / 3 of the volume of the cavity of the pressure-resistant shell; The pressure in the cavity of the pressure-resistant shell is 4 to 6 bar.

5. The fuel reforming system according to claim 3, characterized in that: The fuel outlet is provided with a solenoid valve, and the opening and closing of the fuel outlet is controlled by the solenoid valve.

6. The fuel reforming system according to claim 1, characterized in that: The reformer body also includes a waste heat utilization area and an exhaust gas outlet; the fuel gasification area is arranged in the waste heat utilization area, and the two are not connected; the heating area is connected to the exhaust gas outlet through the waste heat utilization area.

7. The fuel reforming system according to claim 1, characterized in that: The reformer body is barrel-shaped; The spark plug is 0.5 to 1 cm higher than the flame hole.

8. The fuel reforming system according to claim 7, characterized in that: The fuel gasification region, reforming region and heating region are located in the center of the reformer body; the water vapor migration balance region and the methanation region are annularly wrapped around the fuel gasification region, reforming region and heating region.

9. The fuel reforming system according to claim 8, characterized in that: The heating area is annularly wrapped around the reforming area; the reforming area is connected to the water vapor migration balance area through a pipeline.

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