Integrated catalytic combustion reformer and reforming method

Abstract

The invention relates to the field of solid oxide fuel cells, and discloses an integrated catalytic combustion reformer and a reforming method. The reformer component comprises two porous partition plates fixedly arranged on the two sides of the inner shell respectively and a plurality of single-tube structures arranged in parallel, and the two ends of each single-tube structure are fixed to preformed holes of the two porous partition plates respectively; a combustion cavity is formed by gaps between all the single-tube structures and the inner shell, the interiors of the single-tube structures are coated with reforming catalysts, and the outer walls of the single-tube structures are evenly coated with combustion catalysts; the combustion cavity is used for combusting and reacting the mixed combustion gas under the action of a combustion catalyst and providing heat for all the single-tube structures; and the internal cavities of all the single-tube structures are used for absorbing heat by mixing the reformed gas and carrying out reforming reaction under the action of the reforming catalyst to obtain hydrogen-rich mixed gas. According to the catalytic combustion reformer and the reforming method, the technical problems that the energy utilization rate is low and the material cost is increased are solved.

Description

Technical Field

[0001] This application relates to the field of solid oxide fuel cells, and particularly to an integrated catalytic combustion reformer and a reforming method. Background Art

[0002] At present, a solid oxide fuel cell (SOFC for short) is a high-temperature fuel cell that uses solid oxide as an electrolyte material. Taking fuel gas (such as hydrogen, natural gas or fuel oil) and oxygen as reactants, it conducts an electrochemical reaction at high temperature to generate electric energy. SOFC has the advantages of high efficiency, low pollution and multi-fuel adaptability. It can directly use a variety of fuels for power generation and can efficiently convert chemical energy into electric energy.

[0003] The fuel gas used in traditional SOFC is mainly a hydrogen-rich mixture obtained by reforming alkanes. The fuel reforming methods in the SOFC system are mainly divided into three types: steam reforming, partial oxidation reforming and autothermal reforming. All alkane reforming requires a certain reaction temperature. Among them, steam reforming is a strongly endothermic reaction and requires a large amount of heat. Since the fuel gas participating in power generation in the SOFC stack is mainly hydrogen, and the hydrogen conversion rate in steam reforming is strongly related to the temperature of the reforming system, the reforming system needs to be stabilized at a suitable reaction temperature to ensure the generation and supply of fuel hydrogen.

[0004] In related technologies, the heat source for steam reforming is more commonly the combustion of the anode exhaust gas of the fuel cell stack, and the heat of the combustion exhaust gas is transferred to the reformer through a heat exchanger for steam reforming endothermic absorption.

[0005] However, the heat of the combustion exhaust gas is exchanged through gas in an additionally provided heat exchanger. This method will inevitably cause heat loss during the heat exchange process due to the transfer of pipelines and heat exchangers, resulting in a reduction in its energy utilization rate. Moreover, the additional heat exchangers and pipelines will also increase the material cost, which is not conducive to the application and popularization of SOFC. Summary of the Invention

[0006] This application provides an integrated catalytic combustion reformer and a reforming method to solve the technical problems of low energy utilization rate and increased material cost.

[0007] In a first aspect, an embodiment of this application provides an integrated catalytic combustion reformer, comprising:

[0008] A burner component, which comprises a cylindrical inner shell;

[0009] A reformer component, which includes two porous partitions respectively and fixedly arranged on both sides of the inner shell, and several single-tube structures arranged parallel to each other. Both ends of each single-tube structure are respectively fixed in the reserved holes of the two porous partitions; the gaps between all the single-tube structures and the inner shell form a combustion chamber. The inner wall of the single-tube structure is coated with a reforming catalyst, and the outer wall of the single-tube structure is evenly coated with a combustion catalyst.

[0010] The combustion chamber is used for the combustion reaction of the mixed combustion gas under the action of the combustion catalyst and to provide heat to all the single-tube structures; the internal cavities of all the single-tube structures are used for the mixed reforming gas to absorb heat and undergo a reforming reaction under the action of the reforming catalyst to obtain a hydrogen-rich mixed gas.

[0011] Combined with the first aspect, in an embodiment, the single-tube structure includes a tube body and a porous grid carrier. The porous grid carrier divides the internal channel of the tube body into several independent channels; the reforming catalyst is evenly coated on the inner walls of all the independent channels.

[0012] Combined with the first aspect, in an embodiment, the reformer component further includes two funnel-shaped pipes. Each funnel-shaped pipe covers all the reserved holes of a porous partition. The mixed reforming gas flows in from one funnel-shaped pipe, dispersedly flows through all the single-tube structures and undergoes a reforming reaction, and then the hydrogen-rich mixed gas flows out from the other funnel-shaped pipe.

[0013] Combined with the first aspect, in an embodiment, the reformer component further includes a reformer inlet duct and a reformer outlet duct. The reformer inlet duct includes a first gas inlet pipe coaxially connected to a funnel-shaped pipe, and a steam inlet pipe vertically connected to the first gas inlet pipe; the reformer outlet duct is coaxially connected to the other funnel-shaped pipe;

[0014] The mixed reforming gas is formed by mixing the alkane gas in the first gas inlet pipe and the steam in the steam inlet pipe.

[0015] Combined with the first aspect, in an embodiment, two notches are radially opened on the inner shell. The burner component further includes a burner inlet duct and a burner outlet duct correspondingly connected to the two notches. The burner inlet duct includes a second gas inlet pipe perpendicular to the inner shell and an air inlet pipe perpendicular to the second gas inlet pipe; the fuel gas in the second gas inlet pipe and the air in the air inlet pipe are mixed to form a mixed combustion gas, and the burner outlet duct discharges the combustion exhaust gas.

[0016] Combined with the first aspect, in an embodiment, the burner component further includes a first temperature sensor, and the first temperature sensor is arranged on the side wall of the burner outlet duct.

[0017] When the temperature of the combustion exhaust gas is lower than the set exhaust gas temperature threshold, the heat supplied to the reforming reaction is insufficient, and the fuel gas in the second fuel gas inlet pipe is increased in input.

[0018] Combined with the first aspect, in an embodiment, the reformer component further includes a second temperature sensor, and the second temperature sensor is disposed within any one of the single-tube structures;

[0019] During the processes of the combustion reaction and the reforming reaction, when the combustion reaction in the combustion chamber has proceeded for a period of time and the temperature monitored by the second temperature sensor reaches the set reforming reaction temperature, the mixed reformed gas is input into the single-tube structure.

[0020] Combined with the first aspect, in an embodiment, the catalytic combustion reformer further includes a housing and a heat insulation layer. The heat insulation layer covers the outer surfaces of the burner component and the reformer component, and the housing covers the heat insulation layer;

[0021] The housing and the heat insulation layer give way to all the intake and exhaust structures of the burner component and the reformer component.

[0022] In a second aspect, an embodiment of the present application provides a reforming method based on the above-mentioned catalytic combustion reformer, including the following steps:

[0023] S1: The mixed combustion gas is introduced into the combustion chamber, and a combustion reaction occurs under the action of a combustion catalyst, releasing heat:

[0024] S2: After the combustion reaction has proceeded for a period of time, the mixed reformed gas flows in and is split into all the single-tube structures. The mixed reformed gas inside the single-tube structures absorbs heat and undergoes a reforming reaction under the action of a reforming catalyst to obtain a hydrogen-rich mixed gas.

[0025] Combined with the second aspect, in an embodiment, the inner shell is radially provided with two notches and correspondingly provided with a burner intake passage for inputting the mixed combustion gas and a burner exhaust passage for discharging the combustion exhaust gas; the burner component further includes a first temperature sensor, and the first temperature sensor is disposed on the side wall of the burner exhaust passage; the reformer component further includes a second temperature sensor, and the second temperature sensor is disposed within any one of the single-tube structures; step S2 includes:

[0026] When the combustion reaction in the combustion chamber has proceeded for a period of time and the temperature monitored by the second temperature sensor reaches the set reforming reaction temperature, the mixed reformed gas starts to be input into the single-tube structure;

[0027] During the combustion reaction and reforming reaction, when the combustion exhaust gas temperature monitored by the first temperature sensor is lower than the set exhaust gas temperature threshold, the heat supplied to the reforming reaction is insufficient, and the fuel gas input of the second gas intake pipe is increased; when the combustion exhaust gas temperature monitored by the first temperature sensor is higher than the set exhaust gas temperature threshold, the heat supplied to the reforming reaction is sufficient.

[0028] The beneficial effects of the technical solutions provided in the embodiments of the present application include:

[0029] 1. The catalytic combustion reformer of the present application forms a closed structure containing a combustion chamber through an inner shell and two porous partitions. A plurality of single-tube structures are arranged between the two porous partitions. The combustion chamber and the plurality of single-tube structures form two completely independent working areas, one for combustion reaction and the other for reforming reaction. The combustion chamber is used to mix the combustion gas for combustion reaction under the action of a combustion catalyst and provide heat to all single-tube structures. The internal cavities of all single-tube structures are used to mix the reformed gas for reforming reaction under the action of a reforming catalyst to obtain a hydrogen-rich mixed gas. The combustion reaction and the reforming reaction directly exchange heat on the outside and inside of the single-tube structure, which improves the heat transfer efficiency and has a high thermal energy utilization rate. Compared with the traditional steam reforming scheme, no pipelines and heat exchangers are required, which greatly saves material costs. More importantly, after the catalytic combustion reformer of the present application integrates the burner and the reformer together, due to the high premixed combustion temperature, directly setting the combustion reaction on the outer wall of the reformer will cause local instantaneous overheating of the reformer, thereby causing aging and failure of the catalytic reforming catalyst. Although the combustion exhaust temperature can be reduced by increasing the air volume, the combustion flame is uncontrollable and the problem of high-temperature aging and failure of the catalyst cannot be completely avoided. The catalytic combustion reformer of the present application, based on the effect of the combustion catalyst in reducing the activation energy of the reaction, allows the mixed combustion gas that has not reached the ignition point of the fuel gas to undergo catalytic combustion reaction. The catalytic combustion is flameless and the combustion is mild, which can meet the rapid heating of the reformer without causing the catalyst overheating problem. At the same time, it can also realize the integrated design of combustion and reforming to achieve the purpose of reducing energy transfer loss and saving system volume and cost.

[0030] 2. In the catalytic combustion reformer of the present application, a porous mesh carrier divides the tube body into several independent channels, and a reforming catalyst is coated on the inner walls of all independent channels. The reformer structure of multiple single-tube structures and porous mesh carriers can provide more catalyst coating area and higher heat transfer efficiency, which can improve the reforming efficiency and energy utilization; furthermore, the reforming catalyst is coated on the inner wall of the porous mesh carrier, rather than directly on the inner wall of the tube body, which can to a certain extent prevent the reforming catalyst from being aged due to local high temperature, thereby indirectly improving the reforming efficiency.

[0031] 3. In the catalytic combustion reformer of the present application, a first temperature sensor is provided on the side wall of the burner exhaust passage to monitor the temperature of the combustion exhaust gas, and the input amount of the fuel gas in the mixed combustion gas is adjusted according to the temperature of the combustion exhaust gas, ensuring that the heat supplied to the reforming reaction is always sufficient, the conversion rate of the reforming reaction is high and meets the requirements. The input amount of the fuel gas in the mixed combustion gas is adjusted by feedback of the fuel exhaust gas temperature, improving the conversion rate of the reforming reaction. The internal temperature of the single-tube structure is monitored by a second temperature sensor. After the internal temperature of the single-tube structure reaches the set reforming reaction temperature after a period of combustion reaction, the mixed reforming gas is input into the single-tube structure for the reforming reaction, accurately controlling the timing of the input of the mixed reforming gas and improving the conversion efficiency of the reforming reaction. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0033] Figure 1 Schematic diagram of the external structure of the catalytic combustion reformer provided by the embodiment of the present application;

[0034] Figure 2 Cross-sectional view of the catalytic combustion reformer provided by the embodiment of the present application;

[0035] Figure 3 Cross-sectional view of the middle of the reformer main body provided by the embodiment of the present application;

[0036] Figure 4 Axial cross-sectional view of the reformer single tube;

[0037] Figure 5 Curve of reforming rate versus combustion exhaust gas temperature;

[0038] In the figure: 1, burner component; 2, thermal insulation layer; 3, inner shell; 4, reformer intake passage; 5, reformer exhaust passage; 6, burner intake passage; 7, burner exhaust passage; 8, reformer component; 9, combustion chamber; 10, first temperature sensor; 11, outer shell; 12, porous partition; 13, second temperature sensor; 14, funnel-shaped pipe; 401, first gas intake pipe; 402, steam intake pipe; 601, second gas intake pipe; 602, air intake pipe; 81, single-tube structure; 801, tube body; 802, porous grid carrier; 1001, thermocouple wire; 1002, thermocouple seat. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0039] To enable those skilled in the art to better understand the solution of this application, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are only a part of the embodiments of this application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in this application without creative efforts belong to the scope of protection of this application.

[0040] Currently, the mainstream reforming heating technology for SOFC is to burn the stack tail gas using a burner, and the generated heat is transferred to the reformer through heat exchange. However, in the catalytic combustion reformer and reforming method of this application, the burner and the reformer are integrated. The combustion chamber 9 wraps the reformer component 8. The combustion reaction occurs outside the single-tube structure 81 in the combustion chamber 9, and the reforming reaction occurs inside the single-tube structure 81. After the combustion chamber 9 directly dissipates heat, the reformer component 8 directly absorbs heat, reducing the energy loss caused by intermediate heat exchange. At the same time, the integrated structure can also save the overall volume and material cost of the system, solving the technical problems of low energy utilization rate and increased material cost.

[0041] As Figures 1 to 4 shown, an embodiment of an integrated catalytic combustion reformer is disclosed in this application. The catalytic combustion reformer includes a burner component 1 and a reformer component 8.

[0042] The burner component 1 includes a cylindrical inner shell 3.

[0043] The reformer component 8 includes two porous partitions 12 and a number of single-tube structures 81. The two porous partitions 12 are respectively fixedly arranged on both sides of the inner shell 3 to form a closed structure. A number of single-tube structures 81 are arranged parallel to each other, and both ends of each single-tube structure 81 are respectively fixed in the reserved holes of the two porous partitions 12. The gaps between all the single-tube structures 81 and the inner shell 3 form the combustion chamber 9. The reforming catalyst is coated inside the single-tube structure 81, and the combustion catalyst is evenly coated on the outer wall of the single-tube structure 81.

[0044] The combustion chamber 9 is used for the combustion reaction of the mixed combustion gas under the action of the combustion catalyst and to provide heat to all the single-tube structures 81; the internal cavities of all the single-tube structures 81 are used for the reforming reaction of the mixed reforming gas under the action of the reforming catalyst to obtain a hydrogen-rich mixed gas.

[0045] The catalytic combustion reformer of the present application forms a closed structure including a combustion chamber 9 through an inner shell 3 and two porous partitions 12. A plurality of single-tube structures 81 are arranged between the two porous partitions 12. The combustion chamber 9 and the plurality of single-tube structures 81 form two completely independent working areas, one for combustion reaction and the other for reforming reaction. The combustion chamber 9 is used to mix the combustion gas for combustion reaction under the action of a combustion catalyst and provide heat to all single-tube structures 81. The internal cavities of all single-tube structures 81 are used for mixing the reformed gas for reforming reaction under the action of a reforming catalyst to obtain a hydrogen-rich mixed gas. The combustion reaction and the reforming reaction directly exchange heat on the outside and inside of the single-tube structure 81, which improves the heat transfer efficiency and has a high thermal energy utilization rate. Compared with the traditional steam reforming scheme, no pipelines and heat exchangers are required, which greatly saves material costs.

[0046] More importantly, after the catalytic combustion reformer of the present application integrates the burner and the reformer together, due to the high premixed combustion temperature, such as the flame temperature of hydrogen burning in air is 1430°C, and it is even higher in a pure oxygen environment, directly setting the combustion reaction on the outer wall of the reformer will cause local instantaneous overheating of the reformer, thereby causing aging and failure of the reforming catalyst. The current reforming catalyst material is generally nickel-based, which is prone to sintering and carbon deposition above 800°C, thereby affecting the catalytic activity. Although the combustion exhaust temperature can be reduced by increasing the air volume, the combustion flame is uncontrollable and the problem of high-temperature aging and failure of the catalyst cannot be completely avoided. The catalytic combustion reformer of the present application performs catalytic combustion in the combustion chamber 9. The catalytic combustion is flameless and the combustion is mild. The combustion temperature is about 800°C, which can meet the rapid heating of the reformer without causing the catalyst overheating problem. At the same time, it can also realize the integrated design of combustion and reforming to achieve the purpose of reducing energy transfer loss and saving system volume and cost.

[0047] In one embodiment, the single tube structure 81 includes a tube body 801 and a porous mesh carrier 802 . The porous mesh carrier 802 divides the internal channel of the tube body 801 into several independent channels, and the reforming catalyst is evenly coated on the inner walls of all independent channels.

[0048] In the catalytic combustion reformer of the present application, the porous mesh carrier 802 divides the tube body 801 into several independent channels, and the inner walls of all independent channels are coated with a reforming catalyst. The reformer structure of multiple single-tube structures 81 and the porous mesh carrier 802 can provide more catalyst coating area (i.e., reaction activation area) and higher heat transfer efficiency, which can improve the reforming efficiency and energy utilization; further, the reforming catalyst is coated on the inner wall of the porous mesh carrier 802, rather than directly coated on the inner wall of the tube body 801, which can to a certain extent avoid the reforming catalyst from being aged due to local high temperature, thereby indirectly improving the reforming efficiency.

[0049] Preferably, a plurality of single-tube structures 81 are arranged in a rectangular array, and the plurality of single-tube structures 81 correspond one by one to the reserved holes of the porous partition plate 12.

[0050] In one embodiment, the reformer component 8 further includes two funnel-shaped pipes 14, and each funnel-shaped pipe 14 covers all the reserved holes of a porous partition plate 12. The mixed reforming gas flows in from one funnel-shaped pipe 14, dispersedly flows through all the single-tube structures 81 and after the reforming reaction, the hydrogen-rich mixed gas flows out from the other funnel-shaped pipe 14.

[0051] For the catalytic combustion reformer of the present application, two funnel-shaped pipes 14 are used to integrate all the single-tube structures 81 into a mixed reforming gas inlet channel and a mixed reforming gas outlet, providing a structural basis for high-efficiency reforming reaction.

[0052] Furthermore, the reformer component 8 further includes a reformer inlet channel 4 and a reformer exhaust channel 5. The reformer inlet channel 4 includes a first fuel gas inlet pipe 401 and a water vapor inlet pipe 402. The first fuel gas inlet pipe 401 is coaxially connected to one funnel-shaped pipe 14, and the water vapor inlet pipe 402 is vertically connected to the first fuel gas inlet pipe 401. The reformer exhaust channel 5 is coaxially connected to the other funnel-shaped pipe 14, and the reformer exhaust channel 5 is used to discharge the hydrogen-rich mixed gas.

[0053] The mixed reforming gas is formed by mixing the alkane gas in the first fuel gas inlet pipe 401 and the water vapor in the water vapor inlet pipe 402.

[0054] For the catalytic combustion reformer of the present application, the reformer inlet channel 4 and the reformer exhaust channel 5 are respectively arranged corresponding to the two funnel-shaped pipes 14. The reformer inlet channel 4 includes the first fuel gas inlet pipe 401 and the water vapor inlet pipe 402 that are perpendicular to each other. The reformer inlet channel 4 and the funnel-shaped pipe 14 are matched just to be able to achieve sufficient mixing of the alkane gas and the water vapor, providing a good basis for the subsequent reforming reaction.

[0055] In one embodiment, two notches are radially opened on the inner shell 3, and the burner component 1 further includes a burner inlet channel 6 and a burner exhaust channel 7 that are correspondingly connected to the two notches. The burner inlet channel 6 is used to supply the mixed combustion gas to the combustion chamber 9, and the burner exhaust channel 7 is used to discharge the combustion tail gas.

[0056] Specifically, the burner air inlet duct 6 includes a second fuel gas inlet duct 601 perpendicular to the inner shell 3 and an air inlet duct 602 perpendicular to the second fuel gas inlet duct. The second fuel gas inlet duct 601 is used to input heated fuel gas, and the air inlet duct 602 is used to input heated air. The fuel gas in the second fuel gas inlet duct 601 and the air in the air inlet duct 602 are mixed to form a mixed combustion gas, and the mixed combustion gas burns under the catalytic action of a combustion catalyst to generate heat. The burner exhaust duct 7 discharges the combustion exhaust gas.

[0057] In the catalytic combustion reformer of the present application, two notches are radially opened in the inner shell 3 to correspondingly connect the burner air inlet duct 6 and the burner exhaust duct 7, which are used to input the mixed combustion gas and discharge the combustion exhaust gas. The burner air inlet duct 6, the combustion chamber 9, and the burner exhaust duct 7 form an air flow channel completely independent of the single-tube structure 81, forming an efficient heat exchange structure that not only has efficient heat exchange but also is mutually independent.

[0058] Furthermore, the burner component 1 further includes a first temperature sensor 10. The first temperature sensor 10 is disposed on the side wall of the burner exhaust duct 7 and is used to monitor the temperature of the combustion exhaust gas and adjust the input amount of the fuel gas in the mixed combustion gas according to the temperature of the combustion exhaust gas.

[0059] Specifically, when the temperature of the combustion exhaust gas monitored by the first temperature sensor 10 is higher than the set exhaust gas temperature threshold, it indicates that the heat supplied to the reforming reaction is sufficient, and the conversion rate of the reforming reaction is high and meets the requirements. When the temperature of the combustion exhaust gas monitored by the first temperature sensor 10 is lower than the set exhaust gas temperature threshold, it indicates that the heat supplied to the reforming reaction is insufficient, and the conversion rate of the reforming reaction is low and does not meet the requirements. It is necessary to increase the input amount of the fuel gas in the second fuel gas inlet duct 601 of the mixed combustion gas. At this time, the amount of air introduced into the air inlet duct 602 can be dynamically adjusted to ensure that the combustion temperature will not be too high, thereby causing the problem of overheating of the reforming catalyst.

[0060] Specifically, the temperature of the combustion exhaust gas monitored by the first temperature sensor 10 does not exceed the set overheating threshold to prevent the aging of the reforming catalyst.

[0061] In the catalytic combustion reformer of the present application, a first temperature sensor 10 is disposed on the side wall of the burner exhaust duct 7 to monitor the temperature of the combustion exhaust gas and adjust the input amount of the fuel gas in the mixed combustion gas according to the temperature of the combustion exhaust gas, ensuring that the heat supplied to the reforming reaction is always sufficient, the conversion rate of the reforming reaction is high and meets the requirements, and the input amount of the fuel gas in the mixed combustion gas is adjusted by the feedback of the fuel exhaust gas temperature, improving the conversion rate of the reforming reaction.

[0062] Furthermore, the first temperature sensor 10 includes a thermocouple wire 1001 and a thermocouple base 1002. The thermocouple base 1002 is welded and penetrates through the side wall of the burner exhaust duct 7. A channel is formed by drilling a hole at the center position of the thermocouple base 1002, and the thermocouple wire 1001 is inserted into the tube of the burner exhaust duct 7 through the channel. The thermocouple wire 1001 is used to detect the temperature of the combustion exhaust gas discharged from the burner exhaust duct 7 after the combustion reaction.

[0063] Specifically, as Figure 5 shown, in one example, the first temperature sensor 10 can detect the temperature of the combustion exhaust gas, and the conversion degree of the reforming reaction can be judged and controlled by the level of the combustion exhaust gas temperature. For detailed reference, please refer to the following test data, such as Figure 5 in, when the combustion exhaust gas temperature is 650 °C, the conversion rate of the reforming reaction is 85%. When the combustion exhaust gas temperature ≥ 650 °C, it indicates that there is surplus combustion heat and the reforming rate ≥ 85%, and no operation is required; when the combustion exhaust gas temperature < 650 °C, it indicates that there is a lack of heat and the reforming rate < 85%. At this time, the gas volume needs to be increased to provide the heat required by the reformer.

[0064] In one embodiment, the reformer component 8 further includes a second temperature sensor 13, and the second temperature sensor 13 is disposed within any single-tube structure 81.

[0065] When the catalytic combustion reformer starts to work, the combustion reaction is carried out first and then the reforming reaction. When the combustion chamber 9 has carried out the combustion reaction for a period of time and the temperature monitored by the second temperature sensor 13 reaches the set reforming reaction temperature, the temperature required for the reforming reaction is reached, and the mixed reforming gas starts to be input into the single-tube structure 81.

[0066] For the catalytic combustion reformer of the present application, by monitoring the internal temperature of the single-tube structure 81 through the second temperature sensor 13, after the internal temperature of the single-tube structure reaches the set reforming reaction temperature after the combustion reaction for a period of time, the mixed reforming gas is input into the single-tube structure 81 to carry out the reforming reaction, accurately controlling the timing of the input of the mixed reforming gas and improving the conversion efficiency of the reforming reaction.

[0067] In one embodiment, the catalytic combustion reformer further includes a housing 11 and a heat insulation layer 2. The heat insulation layer 2 covers the outer surfaces of the burner component 1 and the reformer component 8, and the housing 11 covers the heat insulation layer 2. The heat insulation layer design of the present application reduces the heat loss of the catalytic combustion reformer and improves the overall energy utilization rate.

[0068] Specifically, the heat insulation layer 2 is composed of a heat insulation material with a low thermal conductivity and high temperature resistance. When the housing 11 and the heat insulation layer 2 are designed for covering, they give way to all the intake and exhaust duct structures (i.e., the reformer intake duct 4, the burner intake duct 6, and the burner exhaust duct 7).

[0069] In one such as Figure 2In the illustrated example, the working principle of the catalytic combustion reformer is as follows:

[0070] During startup, heated fuel gas is introduced into the second fuel gas inlet pipe 601, and heated air is introduced into the air inlet pipe 602. After being mixed in the burner inlet passage 6, it flows into the combustion chamber 9 and contacts the combustion catalyst coated on the outer wall surface of the pipe body 801. Based on the effect of the combustion catalyst in reducing the reaction activation energy, the mixed gas that has not reached the ignition point of the fuel gas can undergo a catalytic combustion reaction. This reaction is mild and produces no flame. The combustion temperature is approximately 800 °C, and it continuously heats the pipe body 801 and its internal structure. The combustion exhaust gas after heat exchange is discharged through the burner exhaust passage 7, and the remaining heat is used to supply heat to other parts of the SOFC system or utilized;

[0071] When the temperature required for the steam reforming reaction is reached in the single-tube structure 81 (i.e., the set reforming reaction temperature, usually 450 °C), the second fuel gas inlet pipe 601 and the air inlet pipe 602 operate unchanged. The first fuel gas inlet pipe 401 is opened to introduce fuel gas using CH4, and the steam inlet pipe 402 is opened to introduce steam. After being mixed in the reformer inlet passage 4, it is distributed to several single-tube structures 81 through a funnel-shaped passage. When the reforming mixed gas passes through the inner passage of the porous grid carrier 802, it contacts the reforming catalyst coated on the passage, thereby undergoing the steam reforming reaction CH4 + H2O = CO + 3H2 (ΔH = 205.8 kJ / mol). This reaction is a strongly endothermic reaction, so during the reaction, the pipe body 801 and the porous grid carrier 802 need to continuously absorb and transfer heat from the external combustion chamber 9 to the reforming reaction, thereby increasing the conversion rate of the fuel gas to produce hydrogen. The hydrogen-rich mixed gas after the reaction is discharged through the reformer exhaust passage 5 and can be directly used in the SOFC system for the electrochemical reaction of the stack to generate electrical energy.

[0072] During the reforming reaction and the combustion reaction, the transfer and utilization of heat are extremely crucial. The insulation layer 2 is filled and wrapped with multiple layers of thermal insulation materials, which are characterized by high temperature resistance and low heat transfer coefficient. The formed heat insulation zone can minimize the heat loss of the inner shell 3 and the high-temperature components inside, thereby improving the energy utilization rate.

[0073] A first temperature sensor 10 is also provided at the burner exhaust passage 7. The temperature of the combustion exhaust gas can be monitored through the first temperature sensor 10, and based on the temperature of the combustion exhaust gas, the reforming reaction degree of the reformer can be judged. For example, under the specified reforming catalyst, coating process, heat exchange size design, space velocity design, and burner design, when the exhaust temperature of the combustion exhaust gas is higher than 650 °C (i.e., the set exhaust gas temperature threshold), it can be considered that the heat of this catalytic combustion reformer is surplus, and the conversion rate of the reforming reaction reaches more than 85% (see Figure 5) When the exhaust gas temperature of the combustion is lower than 650 °C, it can be considered that the heat of this catalytic combustion reformer is insufficient and the conversion rate of the reforming reaction is lower than 85%. Then, it is necessary to increase the gas volume of the second gas inlet pipe 601 to increase the heat provided by combustion to ensure the conversion rate of the reforming reaction. At this time, the air volume introduced into the air inlet pipe 602 can be dynamically adjusted to ensure that the combustion temperature will not be too high, thus causing the problem of catalyst overheating. Specifically, the first temperature sensor 10 monitors and ensures that the exhaust gas temperature of the combustion never exceeds the set over-temperature threshold to prevent the aging of the reforming catalyst.

[0074] Secondly, the present application discloses a reforming method based on the above-mentioned catalytic combustion reformer, which includes the following steps:

[0075] S1: The mixed combustion gas is introduced into the combustion chamber, and a combustion reaction occurs under the action of the combustion catalyst, releasing heat:

[0076] S2: After the combustion reaction proceeds for a period of time, the mixed reforming gas flows in from one of the funnel-shaped channel structures and is shunted to all the single-tube structures 81. The mixed reforming gas inside the single-tube structures 81 absorbs heat and undergoes a reforming reaction under the action of the reforming catalyst to obtain a hydrogen-rich mixture.

[0077] Regarding the reforming method, the reformer component 8 further includes two funnel-shaped pipes 14. Each funnel-shaped pipe 14 covers all the reserved holes of a porous partition 12. The mixed reforming gas flows in from one funnel-shaped pipe 14, dispersedly flows through all the single-tube structures 81 and undergoes a reforming reaction, and then the hydrogen-rich mixture flows out from the other funnel-shaped pipe 14.

[0078] Furthermore, regarding the reforming method, two notches are radially opened on the inner shell 3, and a burner air inlet passage 6 for inputting the mixed combustion gas and a burner exhaust passage 7 for discharging the combustion exhaust gas are correspondingly provided; the burner component 1 further includes a first temperature sensor 10, and the first temperature sensor 10 is arranged on the side wall of the burner exhaust passage 7; the reformer component 8 further includes a second temperature sensor 13, and the second temperature sensor 13 is arranged in any one of the single-tube structures 81; step S2 includes:

[0079] When the combustion reaction in the combustion chamber 9 proceeds for a period of time and the temperature monitored by the second temperature sensor 13 reaches the set reforming reaction temperature, the mixed reforming gas starts to be input into the single-tube structure 81;

[0080] During the process of the combustion reaction and the reforming reaction, when the exhaust gas temperature of the combustion monitored by the first temperature sensor 10 is lower than the set exhaust gas temperature threshold, the heat supplied to the reforming reaction is insufficient, and the input amount of the fuel gas in the second gas inlet pipe 601 of the mixed combustion gas is increased; when the exhaust gas temperature of the combustion monitored by the first temperature sensor 10 is higher than the set exhaust gas temperature threshold, the heat supplied to the reforming reaction is sufficient.

[0081] In the description of the present application, it should be noted that the orientation or positional relationship indicated by terms such as "upper" and "lower" is based on the orientation or positional relationship shown in the drawings. This is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present application. Unless otherwise clearly specified and defined, the terms "installed", "connected" and "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0082] It should be noted that in the present application, relative terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprising", "including" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the existence of additional identical elements in the process, method, article or device including the said element.

[0083] The above are only specific embodiments of the present application, enabling those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to these embodiments shown herein, but rather to the broadest scope consistent with the principles and novel features claimed herein.

Claims

1. An integrated catalytic combustion reformer, characterized in that, Comprising: A burner component (1) comprising a cylindrical inner shell (3); A reformer component (8) comprising two porous partitions (12) respectively fixedly arranged on both sides of the inner shell (3), and a number of single-tube structures (81) arranged parallel to each other. Both ends of each single-tube structure (81) are respectively fixed to the reserved holes of the two porous partitions (12); the gaps between all the single-tube structures (81) and the inner shell (3) form a combustion chamber (9). A reforming catalyst is coated inside the single-tube structures (81), and a combustion catalyst is evenly coated on the outer walls of the single-tube structures (81); The combustion chamber (9) is used for the combustion reaction of the mixed combustion gas under the action of the combustion catalyst and to provide heat to all the single-tube structures (81); the internal cavities of all the single-tube structures (81) are used for the mixed reforming gas to absorb heat and undergo a reforming reaction under the action of the reforming catalyst to obtain a hydrogen-rich mixed gas.

2. The integrated catalytic combustion reformer according to claim 1, wherein: The single-tube structure (81) comprises a tube body (801) and a porous grid carrier (802). The porous grid carrier (802) divides the internal channel of the tube body (801) into several independent channels; the reforming catalyst is evenly coated on the inner walls of all the independent channels.

3. The integrated catalytic combustion reformer according to claim 1, wherein: The reformer component (8) further comprises two funnel-shaped pipes (14). Each funnel-shaped pipe (14) covers all the reserved holes of a porous partition (12). The mixed reforming gas flows in from one funnel-shaped pipe (14), dispersedly flows through all the single-tube structures (81) and undergoes a reforming reaction, and then the hydrogen-rich mixed gas flows out from the other funnel-shaped pipe (14).

4. The integrated catalytic combustion reformer according to claim 3, characterized in that: The reformer component (8) further comprises a reformer intake duct (4) and a reformer exhaust duct (5). The reformer intake duct (4) comprises a first fuel gas intake pipe (401) coaxially connected to a funnel-shaped pipe (14), and a steam intake pipe (402) vertically connected to the first fuel gas intake pipe (401); the reformer exhaust duct (5) is coaxially connected to the other funnel-shaped pipe (14); The mixed reforming gas is formed by mixing the alkane gas in the first fuel gas intake pipe (401) and the steam in the steam intake pipe (402).

5. The integrated catalytic combustion reformer according to claim 1, wherein: Two notches are radially formed in the inner shell (3). The burner component (1) further comprises a burner intake duct (6) and a burner exhaust duct (7) correspondingly connected to the two notches. The burner intake duct (6) comprises a second fuel gas intake pipe (601) perpendicular to the inner shell (3) and an air intake pipe (602) perpendicular to the second fuel gas intake pipe; the fuel gas in the second fuel gas intake pipe (601) and the air in the air intake pipe (602) are mixed to form a mixed combustion gas, and the burner exhaust duct (7) discharges the combustion tail gas.

6. The integrated catalytic combustion reformer according to claim 5, wherein: The burner component (1) further comprises a first temperature sensor (10), and the first temperature sensor (10) is arranged on the side wall of the burner exhaust duct (7); When the temperature of the combustion tail gas is lower than the set tail gas temperature threshold, the heat supplied to the reforming reaction is insufficient, and the fuel gas in the second fuel gas intake pipe (601) is increased in input.

7. An integrated catalytic combustion reformer according to claim 1, characterized in that: The reformer component (8) further includes a second temperature sensor (13), and the second temperature sensor (13) is disposed within any one of the single-tube structures (81); During the combustion reaction and the reforming reaction, when the combustion reaction in the combustion chamber (9) has proceeded for a period of time and the temperature monitored by the second temperature sensor (13) reaches the set reforming reaction temperature, the mixed reforming gas is input into the single-tube structure (81).

8. The integrated catalytic combustion reformer according to claim 1, wherein: The catalytic combustion reformer further includes a housing (11) and a heat-insulating layer (2). The heat-insulating layer (2) covers the outer surfaces of the burner component (1) and the reformer component (8), and the housing (11) covers the heat-insulating layer (2); The housing (11) and the heat-insulating layer (2) leave all the intake and exhaust structures for the burner component (1) and the reformer component (8).

9. A reforming method for the catalytic combustion reformer according to claim 1, characterized in that, It includes the following steps: S1: The mixed combustion gas is introduced into the combustion chamber, and a combustion reaction occurs under the action of the combustion catalyst, releasing heat: S2: After the combustion reaction has proceeded for a period of time, the mixed reforming gas flows in and is shunted to all the single-tube structures (81). The mixed reforming gas inside the single-tube structure (81) absorbs heat and undergoes a reforming reaction under the action of the reforming catalyst to obtain a hydrogen-rich mixed gas.

10. The reforming method according to claim 9, characterized in that: The inner shell (3) is radially provided with two notches and correspondingly provided with a burner intake passage (6) for inputting the mixed combustion gas and a burner exhaust passage (7) for discharging the combustion tail gas; the burner component (1) further includes a first temperature sensor (10), and the first temperature sensor (10) is disposed on the side wall of the burner exhaust passage (7); the reformer component (8) further includes a second temperature sensor (13), and the second temperature sensor (13) is disposed within any one of the single-tube structures (81); Step S2 includes: When the combustion reaction in the combustion chamber (9) has proceeded for a period of time and the temperature monitored by the second temperature sensor (13) reaches the set reforming reaction temperature, the mixed reforming gas starts to be input into the single-tube structure (81); During the combustion reaction and the reforming reaction, when the temperature of the combustion tail gas monitored by the first temperature sensor (10) is lower than the set tail gas temperature threshold, the heat supplied to the reforming reaction is insufficient, and the fuel gas in the second fuel gas intake pipeline (601) is increased in input; when the temperature of the combustion tail gas monitored by the first temperature sensor (10) is higher than the set tail gas temperature threshold, the heat supplied to the reforming reaction is sufficient.

Images