Heating system for high-temperature solid oxide stack

Abstract

The invention discloses a heating system for a high-temperature solid oxide galvanic pile. The heating system comprises an electric heating box, an air inlet pipeline for conveying air to the galvanic pile, a fuel gas inlet pipeline for conveying mixed gas to the galvanic pile, a galvanic pile supporting platform for placing the galvanic pile and a plurality of platform supporting columns for supporting the galvanic pile supporting platform, the mixed gas comprises at least one of hydrogen, methane, natural gas, synthesis gas, ammonia gas, methanol and carbon-based fuel and water vapor; the galvanic pile supporting platform comprises an air inlet interface used for being connected with an air inlet pipeline and a fuel inlet interface used for being connected with a fuel inlet pipeline; a heating wire of the electric heating box is sleeved outside the plurality of platform supporting columns and the supporting platform; and the height of the heating wire is higher than that of an electric pile arranged on the electric pile supporting platform. According to the invention, liquid drops can be prevented from being formed in the high-temperature solid oxide galvanic pile; therefore, the stability of the electrical property in the electric pile is effectively improved, and the fluctuation of voltage and current in the electric pile and the damage to equipment are reduced.

Description

Technical Field

[0001] This invention relates to the field of high-temperature solid oxide fuel cells, and particularly to a heating system for high-temperature solid oxide fuel cells. Background Technology

[0002] The core component of a high-temperature solid oxide fuel cell and electrolyzer (SOFC / SOEC, or SOC) system is the fuel cell stack, which plays a dominant role in performance. The electrolysis temperature of the stack directly determines its performance. In actual testing or operation, the operating temperature of the SOC generally needs to be between 700-900℃.

[0003] In existing technologies, two gas delivery pipelines are generally required for the fuel cell stack. One is an air pipeline, and the other is a mixed gas pipeline containing at least one of hydrogen, methane, natural gas, biogas, syngas, ammonia, methanol, other carbon-based fuels, and water vapor, which can be used as fuel, feedstock, or protective gas.

[0004] The inventors discovered through research that existing high-temperature solid oxide fuel cells have at least the following drawbacks:

[0005] The electrical performance of the fuel cell stack is not stable enough, and it is prone to voltage and current fluctuations.

[0006] The information disclosed in this background section is intended only to enhance the understanding of the overall background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0007] The purpose of this invention is to improve the stability of the electrical performance of the fuel cell stack and reduce its voltage and current fluctuations.

[0008] This invention provides a heating system for a high-temperature solid oxide fuel cell stack, comprising: an electric heating box, an air intake pipe for supplying air to the stack, a gas intake pipe for supplying a mixed gas to the stack, a stack support platform for placing the stack, and a plurality of platform supports for supporting the stack support platform; the mixed gas comprises gaseous fuel and water vapor; the gaseous fuel comprises one or more of hydrogen, methane, natural gas, biogas, syngas, ammonia, methanol, and carbon-based fuels;

[0009] The fuel cell stack support platform includes an air intake interface for connection to the air intake duct, and a fuel intake interface for connection to the fuel intake duct.

[0010] The heating wire of the electric heating box is sleeved outside the multiple platform pillars and the fuel cell support platform, and the height of the heating wire is higher than the height of the fuel cell on the fuel cell support platform.

[0011] Preferably, in this invention, both the air intake pipe and the gas intake pipe are configured as coil structures.

[0012] Preferably, in this invention, the air intake pipe is sleeved outside the gas intake pipe.

[0013] Preferably, in this invention, the cross-sectional area of ​​the air intake pipe is 2-5 times that of the gas intake pipe.

[0014] Preferably, in this invention, the gas flow rate of the air intake pipe is 2-5 times that of the gas flow rate of the gas intake pipe.

[0015] Preferably, in this invention, one or more of the platform support, the air intake pipe, and the gas intake pipe are made of ceramic.

[0016] Preferably, in this invention, the flatness of the fuel cell stack support platform is ≤0.1 micrometers.

[0017] Preferably, in this invention, the number of platform supports is not less than three.

[0018] Preferably, in this invention, the number of platform supports is four.

[0019] Preferably, in this invention, the electric heating box includes multiple heating wires with independently controllable power.

[0020] Preferably, in this invention, the height of the heating wire is higher than the height of the fuel cell stack on the fuel cell stack support platform, including:

[0021] The height of the fuel cell stack on the fuel cell stack support platform is between 1 / 2 and 2 / 3 of the overall height of the heating wire.

[0022] Preferably, in this invention, both the air intake pipe and the gas intake pipe are provided with support frames.

[0023] Preferably, the present invention further includes a thermocouple and a temperature control unit;

[0024] The thermocouple is used to collect temperature data of the air intake pipe and the gas intake pipe;

[0025] The temperature control unit is used to control the power of the heating wire based on the temperature data.

[0026] Preferably, in this invention, controlling the power of the heating wire based on the temperature data includes:

[0027] By controlling the power of the heating wire, the temperature of the air intake pipe and the gas intake pipe is heated to over 600 degrees Celsius.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] The inventors discovered through research that a key reason why the electrical performance of fuel cell stacks is not stable enough and is prone to voltage and current fluctuations is that, in existing technologies, water vapor and room-temperature fuel gas are directly mixed and fed into the fuel cell stack. At this time, due to the large temperature difference between water vapor and room-temperature fuel gas, as well as the large temperature difference between the inside and outside of the fuel cell stack, the water vapor will form droplets in a transient state due to the temperature difference when it enters the fuel cell stack. The changes in electrical performance caused by the droplets will cause fluctuations in the voltage and current of the fuel cell stack, and even damage to the equipment.

[0030] Based on the above research findings, the inventors improved the structure of the heating system for high-temperature solid oxide fuel cell stacks. Specifically, they first established air intake pipes and gas intake pipes, and then installed heating wires of an electric heating box around the air intake pipes and gas intake pipes to preheat the air and the mixed gas. This not only improves the mixing uniformity of gaseous fuel and water vapor, but also prevents the formation of droplets within the high-temperature solid oxide fuel cell stack. Consequently, it effectively improves the stability of the electrical performance within the stack, reduces voltage and current fluctuations within the stack, and minimizes equipment damage.

[0031] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it according to the contents of the specification, and to make the above and other objects, technical features and advantages of the present invention easier to understand, one or more preferred embodiments are listed below and described in detail with reference to the accompanying drawings. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the heating system for high-temperature solid oxide fuel cells described in this invention;

[0033] Figure 2 This is another schematic diagram of the heating system for high-temperature solid oxide fuel cells described in this invention. Detailed Implementation

[0034] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments.

[0035] Unless otherwise expressly stated, throughout the specification and claims, the term "comprising" or its variations such as "including" or "comprises" shall be understood to include the stated elements or components without excluding other elements or other components.

[0036] In this document, for ease of description, spatial relative terms such as “below,” “under,” “down,” “above,” “above,” “upper,” etc., are used to describe the relationship of one element or feature to another element or feature in the accompanying drawings. It should be understood that spatial relative terms are intended to encompass different orientations of an object in use or operation, in addition to those depicted in the figures. For example, if an object in the figure is flipped, an element described as “below” or “under” another element or feature would be oriented “above” that element or feature. Thus, the exemplary term “below” can encompass both the downward and upward orientations. An object may also have other orientations (rotated 90 degrees or other orientations), and the spatial relative terms used herein should be interpreted accordingly.

[0037] In this document, the terms "first," "second," etc., are used to distinguish two different elements or parts, and are not used to define specific positions or relative relationships. In other words, in some embodiments, the terms "first," "second," etc., can also be used interchangeably.

[0038] Example 1

[0039] In order to improve the stability of the electrical performance of the fuel cell stack and reduce its voltage and current fluctuations, reference Figure 1 and Figure 2 This invention provides a heating system for a high-temperature solid oxide fuel cell stack, comprising an electric heating box 01, an air intake pipe 02 for supplying air to the stack, a gas intake pipe 03 for supplying a mixed gas to the stack, a stack support platform 04 for placing the stack, and a plurality of platform supports 05 for supporting the stack support platform; the mixed gas includes gaseous fuel and water vapor; the gaseous fuel includes one or more of hydrogen, methane, natural gas, biogas, syngas, ammonia, methanol, and carbon-based fuels;

[0040] The fuel cell stack support platform 04 includes an air intake interface 41 for connection to an air intake duct 02, and a fuel intake interface 42 for connection to a fuel intake duct 03.

[0041] It should be noted that the fuel intake pipe 03 in the embodiments of the present invention can be used as a pipeline for transporting fuel, raw materials or protective gas.

[0042] The heating wire of the electric heating box 01 is sleeved outside the multiple platform supports 05 and the fuel cell support platform 04, and the height of the heating wire is higher than the height of the fuel cell on the fuel cell support platform 04.

[0043] In this embodiment of the invention, an air intake pipe 02 and a fuel intake pipe 03 are provided below the fuel cell stack support platform 04. Thus, through the air intake port 02 and the fuel intake port 03, air and mixed gas can be supplied to the high-temperature solid oxide fuel cell stack placed on the fuel cell stack support platform 04; the water vapor in the mixed gas can be used as a raw material during electrolysis.

[0044] It should be noted that, in this embodiment of the invention, the fuel cell stack support platform 04 may also be provided with an air outlet 43 and a fuel outlet 44 in addition to the air inlet 41 and the fuel inlet 42.

[0045] In this embodiment of the invention, the air intake pipe 02 and the gas intake pipe 03 have a certain length and are both located at the position of the heating wire of the electric heating box 01. In this way, the air and the gas mixture can be effectively heated by the heating wire before entering the high-temperature solid oxide fuel cell.

[0046] In order to heat the air and gas mixture more thoroughly, preferably, in the embodiments of the present invention, the air intake pipe 02 and the gas intake pipe 03 can also be configured as a coil structure, which can increase the distance of the air and gas mixture in the intake pipe and the heating time.

[0047] In one specific implementation of the present invention, the air intake pipe 02 is sleeved outside the gas intake pipe 03, and the close proximity of the two facilitates heat transfer; thus, the support frames 06 of the air intake pipe 02 and the gas intake pipe 03 can be staggered to support the air intake pipe 02 and the gas intake pipe 03 respectively.

[0048] In this embodiment of the invention, the delivery amounts of air and mixed gas are different. Preferably, the gas flow control position of the air intake pipe 02 can be 2-5 times the gas flow rate of the gas intake pipe 03, or the cross-sectional area of ​​the air intake pipe 02 can be set to 2-5 times the cross-sectional area of ​​the gas intake pipe 03.

[0049] Preferably, the platform support 05, air intake pipe 02, and gas intake pipe 03 in the embodiments of the present invention are made of high-temperature resistant ceramic.

[0050] In this embodiment of the invention, the fuel cell stack support platform 04 is provided with a plurality of platform supports 05 for support. The number of platform supports shall be at least three, and preferably four.

[0051] In addition, preferably, the design requirement for the fuel cell stack support platform 04 in this embodiment of the invention is that its flatness is ≤0.1 micrometers.

[0052] In summary, in the embodiments of the present invention, the inventors have improved the structure of the heating system for high-temperature solid oxide fuel cell stacks. Specifically, they have first established an air intake pipe and a gas intake pipe, and then installed heating wires of an electric heating box around the air intake pipe and the gas intake pipe to preheat the air and the mixed gas. This not only improves the mixing uniformity of gaseous fuel and water vapor, but also avoids the formation of droplets in the high-temperature solid oxide fuel cell stack. As a result, the stability of the electrical performance within the stack is effectively improved, and fluctuations in voltage and current within the stack are reduced, as well as damage to the equipment.

[0053] Example 2

[0054] Furthermore, based on Embodiment 1, this embodiment of the invention also provides a control scheme for the electric heating box, specifically including:

[0055] The electric heating box 01 in this embodiment of the invention includes multiple heating wires with independently controllable power, thermocouples, and a temperature control unit; the thermocouples are used to collect temperature data of the air intake pipe and the gas intake pipe; the temperature control unit is used to control the power of the heating wires according to the temperature data.

[0056] In practical applications, the power of each heating wire can be flexibly controlled based on the temperature data collected by the thermocouples to ensure that the air and gas mixture entering the high-temperature solid oxide fuel cell can reach the set temperature (e.g., 600 degrees Celsius) or higher.

[0057] In a preferred embodiment of the present invention, the overall height of the heating wire is also set so that the height of the fuel cell on the fuel cell support platform 04 is between 1 / 2 and 2 / 3 of the overall height of the heating wire. The inventors have found through research that the middle part of the overall height of the heating wire in the electric heating box 01 is the position where the temperature is most stable. Setting the height of the high-temperature solid oxide fuel cell at this position can ensure that the temperature of the high-temperature solid oxide fuel cell is constant, which helps to maintain the performance and stability of the fuel cell.

[0058] The above-described product can execute the methods provided in the embodiments of the present invention, and has the corresponding functional modules and beneficial effects for executing the methods. Technical details not described in detail in this embodiment can be found in the methods provided in other embodiments of the present invention.

[0059] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A heating system for high-temperature solid oxide fuel cell stacks, characterized in that, include: The device includes an electric heating box, an air intake duct for supplying air to the fuel cell stack, a gas intake duct for supplying a mixed gas to the fuel cell stack, a fuel cell stack support platform for placing the fuel cell stack, and a plurality of platform supports for supporting the fuel cell stack support platform; the mixed gas includes gaseous fuel and water vapor; the gaseous fuel includes one or more of hydrogen, methane, natural gas, biogas, syngas, ammonia, methanol, and carbon-based fuels. The fuel cell stack support platform includes an air intake interface for connection to the air intake duct, and a fuel intake interface for connection to the fuel intake duct. The heating wire of the electric heating box is sleeved outside the multiple platform pillars and the fuel cell support platform, and the height of the heating wire is higher than the height of the fuel cell on the fuel cell support platform.

2. The heating system for high-temperature solid oxide fuel cell stacks according to claim 1, characterized in that, Both the air intake pipe and the gas intake pipe are configured as coil structures.

3. The heating system for high-temperature solid oxide fuel cell stacks according to claim 2, characterized in that, The air intake pipe is fitted outside the gas intake pipe.

4. The heating system for high-temperature solid oxide fuel cell stacks according to claim 3, characterized in that, The cross-sectional area of ​​the air intake pipe is 2-5 times that of the gas intake pipe.

5. The heating system for high-temperature solid oxide fuel cell stacks according to claim 3, characterized in that, The gas flow rate of the air intake pipe is 2-5 times that of the gas intake pipe.

6. The heating system for high-temperature solid oxide fuel cell stacks according to claim 1, characterized in that, One or more of the platform support, the air intake pipe, and the gas intake pipe are made of ceramic.

7. The heating system for a high-temperature solid oxide fuel cell stack according to claim 6, characterized in that, The flatness of the fuel cell stack support platform is ≤0.1 micrometers.

8. The heating system for a high-temperature solid oxide fuel cell stack according to claim 7, characterized in that, The platform shall have no fewer than three pillars.

9. The heating system for a high-temperature solid oxide fuel cell stack according to claim 8, characterized in that, The platform has four support pillars.

10. The heating system for a high-temperature solid oxide fuel cell stack according to claim 1, characterized in that, The electric heating box includes multiple heating wires with independently controllable power.

11. The heating system for a high-temperature solid oxide fuel cell according to claim 10, characterized in that, The height of the heating wire must be higher than the height of the fuel cell stack on the fuel cell stack support platform, including: The height of the fuel cell stack on the fuel cell stack support platform is between 1 / 2 and 2 / 3 of the overall height of the heating wire.

12. The heating system for a high-temperature solid oxide fuel cell stack according to claim 3, characterized in that, Both the air intake pipe and the gas intake pipe are equipped with support frames.

13. The heating system for a high-temperature solid oxide fuel cell according to claim 10, characterized in that, It also includes thermocouples and temperature control units; The thermocouple is used to collect temperature data of the air intake pipe and the gas intake pipe; The temperature control unit is used to control the power of the heating wire based on the temperature data.

14. The heating system for a high-temperature solid oxide fuel cell stack according to claim 13, characterized in that, The step of controlling the power of the heating wire based on the temperature data includes: By controlling the power of the heating wire, the temperature of the air intake pipe and the gas intake pipe is heated to over 600 degrees Celsius.

Images