Power generation device based on high-temperature solid oxide fuel cell

Abstract

The invention relates to the technical field of fuel cell energy recovery, and discloses a power generation device based on a high-temperature solid oxide fuel cell, a carbon dioxide output module comprises the high-temperature solid oxide fuel cell and a calcining furnace, gas fuel is introduced into an anode of the fuel cell, and output carbon dioxide is introduced into the calcining furnace; calcium carbonate is arranged in the calcining furnace; the carbon dioxide circulation module comprises a compressor, a gas storage tank, a carbonization furnace, an expansion machine, a first power generator and a first heat exchanger, carbon dioxide generated after calcium carbonate calcination is compressed by the compressor and then guided into the gas storage tank, the gas storage tank is communicated with the carbonization furnace, and calcium oxide is arranged in the carbonization furnace; residual carbon dioxide in the carbonization furnace is expanded by the expansion machine and then pushes the first power generator to generate power, the expansion machine is communicated with the first heat exchanger, and the first heat exchanger is communicated with the gas storage tank; energy required by calcination is derived from byproduct heat energy, and carbon dioxide is collected in a centralized manner and is used as a circulating material, so that carbon is prevented from being discharged into the atmosphere from the source.

Description

Technical Field

[0001] This invention relates to the technical field of fuel cell energy recovery, and in particular to a power generation device based on a high-temperature solid oxide fuel cell. Background Technology

[0002] Currently, solid oxide fuel cells (SOFCs) have shown significant potential in distributed energy and hydrogen energy applications due to their high energy conversion efficiency and adaptability to various fuels. However, SOFCs generate a large amount of carbon dioxide as a byproduct during the electrochemical reaction process, especially on the anode side.

[0003] Traditional SOFC systems typically release carbon dioxide directly into the atmosphere, leading to decreased energy recovery rates and exacerbating greenhouse gas emissions. Furthermore, existing carbon dioxide capture and utilization technologies are mostly post-processing solutions, such as amine absorption or membrane separation, which are energy-intensive and costly. Simply capturing without utilizing the carbon dioxide results in significant waste. They are also difficult to integrate with SOFC thermal management, leading to further heat waste.

[0004] Therefore, how to efficiently utilize the carbon dioxide and heat of SOFC systems has become an urgent technical problem to be solved. Summary of the Invention

[0005] The technical problem to be solved by this invention is: how to efficiently utilize the carbon dioxide and heat of an SOFC system.

[0006] To address the aforementioned technical problems, this invention provides a power generation device based on a high-temperature solid oxide fuel cell, comprising: a carbon dioxide output module, which includes a high-temperature solid oxide fuel cell and a calcining furnace; the high-temperature solid oxide fuel cell includes a cathode and an anode; air is introduced into the input end of the cathode, and gaseous fuel is introduced into the input end of the anode; carbon dioxide emitted from the anode is introduced into the calcining furnace, which contains calcium carbonate; the calcium carbonate is calcined to produce calcium oxide and carbon dioxide; and a carbon dioxide circulation module, which includes a compressor, a gas storage tank, a carbonization furnace, an expander, a first generator, and a first heat exchanger; the carbon dioxide produced after the calcium carbonate is calcined is compressed by the compressor and introduced into the gas storage tank; the gas storage tank is connected to the carbonization furnace, which contains calcium oxide; the calcium oxide carbonizes with carbon dioxide to produce calcium carbonate; the residual carbon dioxide in the carbonization furnace is expanded by the expander and drives the first generator to generate electricity; the expander is connected to the first heat exchanger, which is connected to the gas storage tank; and the first heat exchanger is used to cool the carbon dioxide.

[0007] In one embodiment, a burner is connected between the anode and the calcining furnace, and oxygen is introduced into the burner. The burner is used to burn the gaseous fuel that has not been fully burned by the anode.

[0008] In one embodiment, a first gas turbine is connected between the burner and the calcining furnace. The first gas turbine is driven by a second generator and rotates under the influence of carbon dioxide to drive the second generator to generate electricity.

[0009] In one embodiment, a water circulation module is also included. The water circulation module includes an external reformer, a separator, and a mixer. The calcining furnace, the external reformer, the separator, and the compressor are connected in sequence. The separator is used to separate carbon dioxide and water. The water separated by the separator is mixed with natural gas through the mixer and then enters the external reformer. The external reformer is used to reform methane and water to produce carbon monoxide and hydrogen. The carbon monoxide and hydrogen enter the anode as gaseous fuels.

[0010] In one embodiment, the water circulation module further includes a flash evaporator. The water separated by the separator is introduced into the first heat exchanger, and then the first heat exchanger absorbs heat and is introduced into the flash evaporator. The flash evaporator is used to flash the water into water vapor, and the water vapor is used to enter the mixer to mix with natural gas.

[0011] In one embodiment, the molar ratio of water vapor to natural gas in the external reformer ranges from 2 to 4.

[0012] In one embodiment, a control valve is connected between the gas storage tank and the carbonization furnace.

[0013] In one embodiment, the output end of the cathode is connected to a second gas turbine, and the second gas turbine is driven by a third generator, which is used to drive the third generator to generate electricity.

[0014] In one embodiment, the input end of the cathode is connected to a second heat exchanger, the output end of the second gas turbine is connected to the second heat exchanger, and the exhaust gas of the second gas turbine is used to heat the air entering the cathode through the second heat exchanger.

[0015] In one embodiment, the calcium oxide produced in the calcining furnace is used in the carbonization furnace, and the calcium carbonate produced in the carbonization furnace is used in the calcining furnace.

[0016] Compared with the prior art, the power generation device based on a high-temperature solid oxide fuel cell according to an embodiment of the present invention has the following advantages: The waste heat from fuel cell combustion drives the calcining furnace, compressing the decomposed carbon dioxide and the burned carbon dioxide together before sending them into the storage tank. The carbonization furnace reacts calcium oxide with carbon dioxide to produce calcium carbonate and releases heat. This heat is transferred to the carbon dioxide gas, thereby driving the carbon dioxide expander to generate electricity. The expanded carbon dioxide flows back to the storage tank, forming a closed loop. The carbon dioxide lost in the carbonization furnace can be replenished by the calcining furnace, forming a complete transcritical carbon dioxide power generation cycle. This combination of chemical energy storage and carbon dioxide recycling realizes the recycling of carbon dioxide. Since there is no carbon dioxide emission, there is no need for capture, reducing energy loss. Moreover, the carbon dioxide can generate electricity during the recycling process, producing additional revenue and significantly improving energy efficiency. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of a power generation device based on a high-temperature solid oxide fuel cell, as exemplarily shown in an embodiment of the present invention.

[0018] Figure 2 This is a schematic diagram of a power generation device including a water circulation module, as exemplarily shown in an embodiment of the present invention.

[0019] Figure 3 This is a schematic diagram of a power generation device for an optimized water circulation module, as exemplarily shown in an embodiment of the present invention.

[0020] Figure 4 This is a schematic diagram of a power generation device that recovers energy from the anode, as exemplarily shown in an embodiment of the present invention.

[0021] Figure label: 1. High-temperature solid oxide fuel cell; 2. Calcining furnace; 11. Cathode; 12. Anode; 3. Compressor; 4. Gas storage tank; 5. Carbonization furnace; 6. Expander; 7. First generator; 8. First heat exchanger; 9. Burner; 10. First gas turbine; 11. Second generator; 12. External reformer; 13. Separator; 14. Mixer; 15. Flash evaporator; 16. Control valve; 17. Second gas turbine; 18. Third generator; 19. Second heat exchanger. Detailed Implementation

[0022] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0023] It should be understood that although the terms first, second, third, etc., may be used in this invention to describe various information, this information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, first information may also be referred to as second information without departing from the scope of this invention, and similarly, second information may also be referred to as first information. Depending on the context, the word "if" as used herein may be interpreted as "when," "when," or "in response to determination."

[0024] Driven by both the "dual carbon" goals and the transformation of the energy structure, solid oxide fuel cells (SOFCs) have become highly competitive energy devices in distributed power generation, transportation power, and hydrogen energy storage due to their high energy conversion efficiency and the outstanding advantage of being able to directly utilize various fuels such as hydrogen, natural gas, and biomass gas. However, the fuel oxidation reaction on the anode side of SOFCs inevitably produces a large amount of carbon dioxide. When methane is used as fuel, every 1 mol of methane consumed is accompanied by 1 mol of carbon dioxide generated. This emission problem has become a key bottleneck restricting the large-scale application of the technology.

[0025] Traditional SOFC systems lack integrated carbon processing modules, resulting in the direct release of carbon dioxide into the atmosphere. This not only leads to underutilization of carbon resources in the fuel and reduced overall system energy efficiency but also exacerbates the greenhouse effect. Existing carbon capture technologies, such as amine absorption, require a portion of the system's electricity generation for solvent regeneration, while membrane separation methods face challenges such as high membrane module costs and poor fouling resistance. Furthermore, these post-treatment technologies cannot effectively match the medium- and high-temperature waste heat generated during SOFC operation, resulting in the significant loss of high-quality heat.

[0026] How to couple the carbon dioxide emissions of SOFC with waste heat recovery to achieve in-situ conversion of carbon resources and cascade utilization of energy has become the core direction for breaking through the bottleneck of SOFC technology application, and is of great significance to promoting the development of low-carbon energy systems.

[0027] Based on this, the inventors innovated from the perspective of chemical energy storage, such as... Figure 1 As shown, a preferred embodiment of the present invention provides a power generation device based on a high-temperature solid oxide fuel cell 1, comprising: a carbon dioxide output module and a carbon dioxide circulation module.

[0028] The carbon dioxide output module includes a high-temperature solid oxide fuel cell 1 and a calcining furnace 2. The high-temperature solid oxide fuel cell 1 includes a cathode 101 and an anode 102. Air is introduced into the input end of the cathode 101, and gaseous fuel is introduced into the input end of the anode 102. The carbon dioxide emitted by the anode 102 is introduced into the calcining furnace 2. The calcining furnace 2 contains calcium carbonate, and calcium carbonate is calcined to produce calcium oxide and carbon dioxide.

[0029] The carbon dioxide circulation module includes a compressor 3, a gas storage tank 4, a carbonization furnace 5, an expander 6, a first generator 7, and a first heat exchanger 8. The carbon dioxide produced after the calcium carbonate is calcined is compressed by the compressor 3 and introduced into the gas storage tank 4. The gas storage tank 4 is connected to the carbonization furnace 5, which contains calcium oxide. The calcium oxide and carbon dioxide are carbonized to produce calcium carbonate. The residual carbon dioxide in the carbonization furnace 5 is expanded by the expander 6 and drives the first generator 7 to generate electricity. The expander 6 is connected to the first heat exchanger 8, and the first heat exchanger 8 is connected to the gas storage tank 4. The first heat exchanger 8 is used to cool the carbon dioxide.

[0030] The outstanding advantage of this invention lies in the synergistic optimization of energy and carbon resources. By deeply coupling the waste heat of the SOFC system with carbon dioxide, it simultaneously solves the dual problems of energy waste and carbon emissions in traditional systems.

[0031] The power generation device cleverly utilizes the high-temperature waste heat naturally generated in the SOFC electrochemical reaction to drive the operation of the calcining furnace 2, so that the energy required for calcium carbonate calcination comes entirely from the system's own by-product heat energy, without the need for additional external energy consumption. Compared with the traditional calcination process that relies on an independent heat source, this significantly reduces energy loss and also solves the industry pain point of SOFC waste heat being difficult to recover efficiently.

[0032] During this process, the carbon dioxide output from SOFC anode 102 and the carbon dioxide produced by the decomposition of calciner 2 are collected together and used as recycled materials, thus avoiding carbon emissions into the atmosphere from the source and eliminating the high-energy-consuming carbon capture process in traditional systems.

[0033] The reaction between calcium oxide and carbon dioxide in carbonization furnace 5 not only fixes carbon but also provides heating energy for the carbon dioxide in the cycle through chemical exothermics. This ensures that the gas has sufficient thermal energy before entering expander 6, thereby efficiently driving expander 6 to drive the first generator 7 to generate electricity, bringing additional electrical energy revenue to the system. This breaks the traditional SOFC model that relies solely on electrochemical reactions for power generation. Simultaneously, the carbon dioxide exiting expander 6 is returned to storage tank 4 after heat exchange in the first heat exchanger 8, forming a complete cycle of "generation-utilization-return-replenishment." The carbon dioxide lost in carbonization furnace 5 can be replenished by calcination furnace 2, ensuring cycle stability while achieving zero-emission operation of carbon dioxide.

[0034] Overall, the power generation device of this invention organically integrates chemical energy storage and carbon dioxide recycling. It reduces energy loss through waste heat recovery and carbon recycling, and enhances the overall system benefits through additional power generation, resulting in a qualitative leap in the energy utilization efficiency of SOFCs. Its design, which eliminates the need for additional carbon capture equipment and relies on its own energy to complete the cycle, not only reduces system operating costs but also aligns with the needs of low-carbon energy development.

[0035] In an exemplary embodiment, the reaction temperature of calcium oxide and carbon dioxide in the carbonization furnace 5 is around 500 to 700 degrees Celsius. If the temperature is too low, the reaction rate will be relatively slow, and if the temperature is too high, it may cause CaCO3 to decompose.

[0036] In one embodiment, a burner 9 is connected between the anode 102 and the calcining furnace 2. Oxygen is introduced into the burner 9, which is used to burn the gaseous fuel that is not fully burned by the anode 102.

[0037] An oxygen-bearing burner 9 is added between the anode 102 and the calcining furnace 2. The burner 9 can fully combust the unreacted fuel discharged from the anode 102, converting residual chemical energy into heat energy and avoiding fuel waste. The generated high-temperature heat energy, together with the waste heat from the SOFC, powers the calcining furnace 2, solving the problem of insufficient calcination energy caused by SOFC load fluctuations and ensuring continuous and efficient calcination.

[0038] Meanwhile, the additional carbon dioxide generated from fuel combustion can replenish the carbon cycle, alleviate carbon source loss in carbonization furnace 5, and reduce the material consumption pressure in calcination furnace 2. In addition, the complete combustion of unburned fuel reduces the combustible components in the exhaust gas, avoiding the risk of gas accumulation.

[0039] Furthermore, in another embodiment of the present invention, a first gas turbine 10 is connected between the burner 9 and the calcining furnace 2. The first gas turbine 10 is connected to the second generator 11 in a transmission connection. The first gas turbine 10 is used to rotate under the impetus of carbon dioxide to drive the second generator 11 to generate electricity.

[0040] A first gas turbine 10 and a matching second generator 11 are added between the burner 9 and the calcining furnace 2, realizing the cascade recovery of energy. Unburned fuel reacts with oxygen to generate high-temperature and high-pressure gas, which first drives the gas turbine to rotate, driving the second generator 11 to generate additional electricity, fully extracting the kinetic energy in the gas and allowing the residual energy of the fuel to be reused. The gas after the turbine has done work still retains a certain temperature and pressure, which can continue to supply energy to the calcining furnace 2 without affecting the calcium carbonate calcination demand and avoiding energy waste.

[0041] This design increases electricity production on top of the existing carbon cycle benefits, further enhancing the overall system benefits, while optimizing the energy utilization chain to further improve the energy conversion rate of the SOFC system.

[0042] In one embodiment, a water circulation module is also included, which includes an external reformer 12, a separator 13, and a mixer 14. The calcining furnace 2, the external reformer 12, the separator 13, and the compressor 3 are connected in sequence. The separator 13 is used to separate carbon dioxide and water. The water separated by the separator 13 is mixed with natural gas through the mixer 14 and then enters the external reformer 12. The external reformer 12 is used to reform methane and water to generate carbon monoxide and hydrogen. The carbon monoxide and hydrogen enter the anode 102 as gaseous fuels.

[0043] The introduction of the water circulation module further improves the resource utilization rate of the system. After the gas discharged from the calciner 2 is processed by the external reformer 12 and the separator 13, the separator 13 separates carbon dioxide and water. The carbon dioxide enters the compressor 3 to continue the carbon cycle, while the separated water is mixed with natural gas and returned to the external reformer 12 as raw material for fuel reforming.

[0044] This embodiment converts system byproduct water into renewable fuel resources, reducing reliance on external water resources and lowering operating costs. Simultaneously, the carbon monoxide and hydrogen generated during reforming are highly efficient fuels for SOFC anode 102, achieving fuel self-sufficiency and recycling. Combined with carbon cycling, this further enhances the system's overall energy efficiency, making energy and resource utilization more sustainable.

[0045] Furthermore, in order to more fully recover and utilize energy, in one embodiment of the present invention, the water circulation module also includes a flash evaporator 15. The water separated by the separator 13 is introduced into the first heat exchanger 8, and then the first heat exchanger 8 absorbs heat and is introduced into the flash evaporator 15. The flash evaporator 15 is used to flash the water into water vapor, and the water vapor is used to enter the mixer 14 to mix with natural gas.

[0046] The introduction of flash evaporator 15 establishes an energy interaction bridge between the carbon dioxide cycle and the water cycle, enabling more precise energy recovery and more efficient resource utilization. The water separated by separator 13 is first introduced into the first heat exchanger 8 to absorb heat transferred during the carbon dioxide cycle. Although it returns to a liquid state after losing its own heat, this process achieves heat transfer across cycles, providing support for carbon dioxide heating. Subsequently, flash evaporator 15 converts this liquid water into water vapor, solving the problem of low vaporization rate of the water exiting separator 13, allowing the water to enter the mixer 14 in a form more readily involved in the reaction and mix with natural gas.

[0047] Water vapor not only enhances the reforming efficiency of methane and water in the external reformer 12, but also optimizes the energy and form of the system's byproduct water, avoiding the loss of reaction efficiency due to insufficient vaporization during the circulation. This design allows the energy demands of the two cycles to complement each other, further tapping into the value of residual energy within the system and making overall energy utilization more efficient.

[0048] In the water circulation and fuel reforming system of this invention, the reaction efficiency of the external reformer 12 directly determines the quality of the SOFC anode 102 fuel and the system energy consumption, while the ratio of steam to natural gas is the core parameter for controlling the reforming effect. For example, the molar ratio of the two in the external reformer 12 is set to a range of 2 to 4, which is the molar ratio of steam to methane in natural gas. This numerical range is determined based on the reaction mechanism and system compatibility.

[0049] From the perspective of reaction requirements, a lower limit of 2 can meet the basic reaction requirements of methane steam reforming, avoiding the formation of carbon deposits due to insufficient steam in the methane cracking process. This reduces the amount of carbon deposits adhering to the reformer catalyst surface and the porous structure of SOFC anode 102, lowering the probability of catalyst deactivation and electrode blockage. Setting the upper limit of 4 allows for the full conversion of methane into carbon monoxide and hydrogen through excess steam, increasing the content of effective components in the fuel gas, while avoiding energy waste caused by excessive steam, thus achieving a balance between reaction efficiency and energy consumption.

[0050] In one embodiment of the present invention, a control valve 16 is connected between the gas storage tank 4 and the carbonization furnace 5. When the fuel cell is working normally, the high-temperature waste heat utilization and carbon dioxide storage processes are in operation, while the carbonization furnace 5 and the expander 6 are not working in a cycle. When the fuel cell is shut down or the carbon dioxide storage is too high, the control valve 16 is opened, and the carbonization furnace 5 and the expander 6 are put into operation in a cycle, realizing the recycling of stored carbon dioxide and secondary power generation.

[0051] In one embodiment, the output end of the cathode 101 is connected to a second gas turbine 17, and the second gas turbine 17 is driven by a third generator 18. The second gas turbine 17 is used to drive the third generator 18 to generate electricity. The addition of the second gas turbine 17 and the matching third generator 18 to the output end of the cathode 101 further improves the energy cascade recovery system of the system and realizes the efficient recovery of the exhaust gas energy of the SOFC cathode 101.

[0052] In one embodiment, the input end of the cathode 101 is connected to a second heat exchanger 19, and the output end of the second gas turbine 17 is connected to the second heat exchanger 19. The exhaust gas of the second gas turbine 17 is used to heat the air that enters the cathode 101 through the second heat exchanger 19.

[0053] After the second gas turbine 17 drives the third generator 18, the exhaust gas, although its pressure decreases, still retains residual heat of over 100 degrees Celsius. In traditional designs, this heat is often directly dissipated, resulting in energy waste. In this embodiment, the second heat exchanger 19 transfers this residual heat to the cold air entering the cathode 101, significantly increasing the intake air temperature.

[0054] When preheated air enters the SOFC cathode 101, the amount of heat required to reach the reaction temperature is reduced, significantly lowering the system's heat load and energy consumption. Simultaneously, the increased intake air temperature optimizes the oxygen reduction reaction kinetics at cathode 101, improving electrochemical reaction efficiency and SOFC power generation stability. This creates a closed loop of "power generation - waste heat preheating" for the gas turbine, echoing the energy recovery mechanisms of the carbon and water cycles mentioned earlier. This ensures that byproduct energy from each stage of the system is fully captured, further improving overall energy utilization efficiency while reducing the environmental impact of heat emissions, enhancing the practicality and economy of the device.

[0055] In one embodiment, the calcium oxide produced by the calcining furnace 2 is used in the carbonization furnace 5, and the calcium carbonate produced by the carbonization furnace 5 is used in the calcining furnace 2. The circulation between the solids constitutes a third circulation in addition to the carbon dioxide circulation and the water circulation. The directness of the solid circulation is a prominent advantage. Compared with gaseous and liquid media, the handling and transportation of calcium oxide and calcium carbonate do not require complex compression and heat exchange equipment. It can be completed by conventional material conveying devices, which greatly reduces the investment and maintenance difficulty of the system equipment.

[0056] Compared with the prior art, the power generation device based on a high-temperature solid oxide fuel cell 1 according to an embodiment of the present invention has the following advantages: The waste heat from fuel cell combustion drives the calcining furnace 2, compressing the decomposed carbon dioxide and the burned carbon dioxide together before they enter the storage tank 4. The carbonization furnace 5 uses calcium oxide to react with carbon dioxide to generate calcium carbonate and releases heat. The heat is transferred to the carbon dioxide gas, thereby driving the carbon dioxide expander 6 to generate electricity. The expanded carbon dioxide flows back to the storage tank 4 to form a closed loop. The carbon dioxide lost in the carbonization furnace 5 can be replenished by the calcining furnace 2, forming a complete carbon dioxide cycle. Combining chemical energy storage with carbon dioxide cycle realizes the recycling of carbon dioxide. Since there is no carbon dioxide emission, there is no need to capture it, reducing energy loss. Moreover, the carbon dioxide can generate electricity during the cycle, generating additional revenue and significantly improving energy utilization efficiency.

[0057] The power generation device in this invention operates with energy cascade utilization and multi-cycle synergy as its core. The specific process is as follows: Air preheated by the second heat exchanger 19 enters the SOFC cathode 101. A mixed fuel of carbon monoxide and hydrogen, generated by the external reformer 12, is introduced into the anode 102. The two undergo an electrochemical reaction within the SOFC to achieve preliminary power generation. The exhaust gas from the anode 102, containing unburned fuel and carbon dioxide, first enters the burner 9 and mixes with oxygen for complete combustion. The resulting high-temperature heat energy, along with the SOFC's own waste heat, is transported to the calcining furnace 2 to provide energy for the calcination of calcium carbonate within the furnace. The generated calcium oxide is directly transported to the carbonization furnace 5, while the carbon dioxide produced during calcination enters the subsequent cycle.

[0058] The carbon dioxide discharged from the calcining furnace 2 combines with the carbon dioxide in the exhaust gas from the burner 9, is compressed by the compressor 3, stored in the gas storage tank 4, and then sent to the carbonization furnace 5 to react with calcium oxide to produce calcium carbonate. This calcium carbonate flows back to the calcining furnace 2 to complete the solid cycle. The residual carbon dioxide in the carbonization furnace 5 enters the expander 6 to do work, driving the first generator 7 to generate additional electricity. After doing work, the gas releases heat through the first heat exchanger 8 and then flows back to the gas storage tank 4 to close the carbon cycle. At the same time, the exhaust gas from the calcining furnace 2 is treated by the external reformer 12 and separator 13. The separated carbon dioxide enters the compressor 3, while the water is first introduced into the first heat exchanger 8 to absorb heat, and then flashed into water vapor by the flash evaporator 15. After mixing with natural gas, it flows back to the external reformer 12. The fuel gas generated by the reforming is sent to the anode 102 to complete the water cycle and fuel cycle.

[0059] The high-temperature and high-pressure exhaust gas discharged from the cathode 101 first drives the second gas turbine 17 to drive the third generator 18 to generate electricity. The exhaust gas after doing work is passed into the second heat exchanger 19 to preheat the cold air to be entered into the cathode 101, realizing energy recovery on the cathode 101 side. The first gas turbine 10 between the burner 9 and the calcining furnace 2 uses the energy of the gas after combustion to drive the second generator 11 to generate electricity, further tapping the residual energy.

[0060] In summary, this invention constructs a three-tiered closed-loop cycle of "carbon-water-solids," fundamentally changing the energy waste and carbon emission problems of traditional SOFC systems. In the carbon cycle, carbon dioxide is captured, reacted, and recovered to achieve zero emissions, eliminating the need for additional carbon treatment equipment and reducing energy consumption. The water cycle converts by-product water into fuel reforming feedstock, reducing dependence on external water resources. The solids cycle achieves self-sufficiency in raw materials through the interconversion of calcium oxide and calcium carbonate, avoiding material procurement and processing costs.

[0061] The energy utilization system forms a tiered recovery system: SOFC electrochemical reaction power generation is at its core, with the first, second, and third generators respectively utilizing combustion gas, carbon cycle gas, and cathode 101 tail gas for secondary energy utilization. Combined with waste heat recovery from various heat exchangers, this improves the overall energy efficiency of the system compared to traditional devices. The highly integrated modules eliminate the need for external energy sources to drive the cycle, reducing operating costs; it also avoids fuel waste and carbon buildup, extending the lifespan of the SOFC. Overall, the device achieves almost complete resource recycling, complete energy recovery, and zero emissions, providing a highly efficient and low-carbon technical solution for the large-scale application of SOFCs.

[0062] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present invention, and these improvements and substitutions should also be considered within the scope of protection of the present invention.

Claims

1. A power generation device based on a high-temperature solid oxide fuel cell, characterized in that, include: A carbon dioxide output module, comprising a high-temperature solid oxide fuel cell (1) and a calcining furnace (2), wherein the high-temperature solid oxide fuel cell (1) comprises a cathode (101) and an anode (102), wherein air is introduced into the input end of the cathode (101) and gaseous fuel is introduced into the input end of the anode (102), and the carbon dioxide emitted by the anode (102) is introduced into the calcining furnace (2), wherein the calcining furnace (2) contains calcium carbonate, and the calcium carbonate is calcined to produce calcium oxide and carbon dioxide; The carbon dioxide circulation module includes a compressor (3), a gas storage tank (4), a carbonization furnace (5), an expander (6), a first generator (7), and a first heat exchanger (8). The carbon dioxide produced after the calcium carbonate is calcined is compressed by the compressor (3) and introduced into the gas storage tank (4). The gas storage tank (4) is connected to the carbonization furnace (5). The carbonization furnace (5) contains calcium oxide. The calcium oxide is carbonized with carbon dioxide to generate calcium carbonate. The residual carbon dioxide in the carbonization furnace (5) is expanded by the expander (6) and drives the first generator (7) to generate electricity. The expander (6) is connected to the first heat exchanger (8). The first heat exchanger (8) is connected to the gas storage tank (4). The first heat exchanger (8) is used to cool the carbon dioxide.

2. The power generation device according to claim 1, characterized in that, A burner (9) is connected between the anode (102) and the calcining furnace (2). Oxygen is introduced into the burner (9), which is used to burn the gaseous fuel that is not fully burned by the anode (102).

3. The power generation device according to claim 2, characterized in that, A first gas turbine (10) is connected between the burner (9) and the calcining furnace (2). The first gas turbine (10) is connected to the second generator (11) in a transmission connection. The first gas turbine (10) is used to rotate under the drive of carbon dioxide to drive the second generator (11) to generate electricity.

4. The power generation device according to claim 1, characterized in that, It also includes a water circulation module, which includes an external reformer (12), a separator (13) and a mixer (14). The calcining furnace (2), the external reformer (12), the separator (13) and the compressor (3) are connected in sequence. The separator (13) is used to separate carbon dioxide and water. The water separated by the separator (13) is mixed with natural gas through the mixer (14) and then enters the external reformer (12). The external reformer (12) is used to reform methane and water to generate carbon monoxide and hydrogen. The carbon monoxide and the hydrogen are used as gaseous fuels and enter the anode (102).

5. The power generation device according to claim 4, characterized in that, The water circulation module also includes a flash evaporator (15). The water separated by the separator (13) is introduced into the first heat exchanger (8), and then the first heat exchanger (8) absorbs heat and is introduced into the flash evaporator (15). The flash evaporator (15) is used to flash water into water vapor, and the water vapor is used to enter the mixer (14) to mix with the natural gas.

6. The power generation device according to claim 5, characterized in that, The ratio of the molar amounts of water vapor and natural gas in the external reformer (12) ranges from 2 to 4.

7. The power generation device according to claim 1, characterized in that, A control valve (16) is connected between the gas storage tank (4) and the carbonization furnace (5).

8. The power generation device according to claim 1, characterized in that, The output end of the cathode (101) is connected to a second gas turbine (17), and the second gas turbine (17) is driven by a third generator (18). The second gas turbine (17) is used to drive the third generator (18) to generate electricity.

9. The power generation device according to claim 8, characterized in that, The input end of the cathode (101) is connected to a second heat exchanger (19), and the output end of the second gas turbine (17) is connected to the second heat exchanger (19). The exhaust gas of the second gas turbine (17) is used to heat the air entering the cathode (101) via the second heat exchanger (19).

10. The power generation device according to claim 1, characterized in that, The calcium oxide produced by the calcining furnace (2) is used in the carbonization furnace (5), and the calcium carbonate produced by the carbonization furnace (5) is used in the calcining furnace (2).

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