Multifunctional power generation system and method based on reversible solid oxide fuel cell

Abstract

The application discloses a kind of multifunctional power generation system and method based on reversible solid oxide fuel cell, the multifunctional power generation system includes reversible solid oxide fuel cell cycle subsystem, closed carbon dioxide cycle subsystem and forced combustion cycle subsystem, the reversible solid oxide fuel cell cycle subsystem is respectively coupled with the closed carbon dioxide cycle subsystem and the forced combustion cycle subsystem, so that multifunctional power generation system has pure oxygen efficient power generation mode, air efficient power generation mode, wide power generation mode, wide power generation mode and energy storage mode;Wherein, the reversible solid oxide fuel cell cycle subsystem is used to work in pure oxygen efficient power generation mode, air efficient power generation mode and energy storage mode, and the forced combustion cycle subsystem is used to improve system power generation power and preheat system.The application can realize efficient power generation, water surface underwater cross-medium operation, wide load variation and energy storage and use integration and other functions.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power generation systems, and further relates to a multifunctional power generation system and method based on a reversible solid oxide fuel cell. BACKGROUND

[0002] In the field of future power systems, especially in the field of marine vessels, there is a trend towards high efficiency, high energy density, wide load range, integrated energy storage and utilization, and cross-medium operation. Existing single power generation systems, such as traditional internal combustion engine power generation systems, gas turbines, diesel engines, etc., are difficult to meet the diversified needs of marine power systems and are difficult to achieve underwater and surface cross-medium operation. Traditional closed external combustion engine power generation systems, such as steam turbines, are also difficult to achieve integrated energy storage and utilization design. New electrochemical power generation systems, such as fuel cell power generation systems, also have low output power and other problems.

[0003] A reversible solid oxide fuel cell (RSOFC) is a full solid-state electrochemical energy conversion device that integrates a solid oxide fuel cell (SOFC) and a solid oxide electrolysis cell (SOEC). The reversible solid oxide fuel cell can efficiently convert chemical energy in fuel into electrical energy, achieving efficient energy utilization. It can also store external electrical energy in fuel, achieving efficient energy storage. Closed carbon dioxide power cycle technology is a high-efficiency, high-power-density, wide-load-range closed power cycle technology, and is a strong competitor for the next generation of thermal power conversion technology.

[0004] Therefore, it is necessary to design a multifunctional power generation system and method based on a reversible solid oxide fuel cell, which deeply couples the reversible solid oxide fuel cell with the carbon dioxide power cycle technology, amplifies the advantages, complements the shortcomings, realizes energy cascade utilization and integrated energy storage and utilization, and ultimately meets the diversified needs of future ship power generation systems. SUMMARY

[0005] To solve the above technical problems, the present application aims to provide a multifunctional power generation system and method based on a reversible solid oxide fuel cell, which can realize efficient power generation, underwater and surface cross-medium operation, wide load range, and integrated energy storage and utilization.

[0006] In order to achieve the above-mentioned purpose, the application provides a multifunctional power generation system based on reversible solid oxide fuel cell, comprising a reversible solid oxide fuel cell cycle subsystem, a closed carbon dioxide cycle subsystem and a forced combustion cycle subsystem, the reversible solid oxide fuel cell cycle subsystem is coupled with the closed carbon dioxide cycle subsystem and the forced combustion cycle subsystem respectively, so that the multifunctional power generation system has a pure oxygen high-efficiency power generation mode, an air high-efficiency power generation mode, a wide power generation mode and an energy storage mode; wherein the reversible solid oxide fuel cell cycle subsystem is used for working in the pure oxygen high-efficiency power generation mode, the air high-efficiency power generation mode, the wide power generation mode and the energy storage mode, the closed carbon dioxide cycle subsystem is used for working in the pure oxygen high-efficiency power generation mode, the air high-efficiency power generation mode and the wide power generation mode, and the forced combustion cycle subsystem is used for improving the system power generation power and preheating the system.

[0007] In some embodiments, the reversible solid oxide fuel cell cycle subsystem comprises a fuel separator, an oxygen separator, a tail gas separator, a water supply and storage system, a carbon dioxide supply and storage system, a fuel supply and storage system, an oxygen supply and storage system, a fuel electrode mixer, an oxygen electrode mixer, a fuel electrode multi-stream preheater, an oxygen electrode multi-stream preheater, a multi-stream cooler, a reversible solid oxide fuel cell, an afterburning chamber and a forced combustion chamber;

[0008] The reversible solid oxide fuel cell has a fuel electrode and an oxygen electrode, the fuel electrode is connected with the cold and hot ends of the fuel electrode multi-stream preheater and the afterburning chamber respectively, the oxygen electrode is connected with the cold and hot ends of the oxygen electrode multi-stream preheater and the afterburning chamber respectively, and the afterburning chamber is connected with the hot ends of the oxygen electrode multi-stream preheater and the fuel electrode multi-stream preheater respectively;

[0009] The fuel supply and storage system is connected with the fuel separator, the combustion electrode mixer and the forced combustion chamber respectively, the oxygen supply and storage system is connected with the oxygen separator, the oxygen electrode mixer and the forced combustion chamber respectively, the carbon dioxide supply and storage system is connected with the fuel electrode mixer and the fuel separator respectively, and the water supply and storage system is connected with the fuel electrode mixer, the oxygen electrode mixer, the fuel separator, the oxygen separator, the tail gas separator, the hot end of the oxygen electrode multi-stream preheater and the hot end of the fuel electrode multi-stream preheater respectively;

[0010] The fuel separator is connected with the oxygen separator, the tail gas separator is connected with the multi-stream cooler, the oxygen supply and storage system is connected with the atmospheric environment, and the multi-stream cooler is connected with the atmospheric environment.

[0011] In some embodiments, the afterburner is connected to the heat side inlet of the heater, the heater is connected to the fuel multi-stream preheater and the oxygen multi-stream preheater, and the heater is connected to the afterburner and the afterburner is connected to the afterburner heat exchanger.

[0012] In some embodiments, the closed carbon dioxide cycle subsystem comprises a compressor, a turbine, a recuperator, a heater, and an electric machine, the heat side inlet of the heater is connected to the afterburner, the heat side outlet of the heater is connected to the fuel multi-stream preheater and the oxygen multi-stream preheater, the cold side outlet of the heater is connected to the afterburner heat exchanger, the turbine is connected to the afterburner heat exchanger, the heat side outlet of the recuperator is connected to the multi-stream cooler, and the low pressure inlet and the high pressure outlet of the compressor are connected to the carbon dioxide storage system.

[0013] In some embodiments, the system further comprises:

[0014] A plurality of control valves are arranged in the reversible solid oxide fuel cell cycle subsystem, the closed carbon dioxide cycle subsystem, and the afterburner cycle subsystem, respectively, for controlling the working states of the components in the subsystems.

[0015] According to another aspect of the present application, the present application further provides a method for operating a reversible solid oxide fuel cell based multifunctional power generation system as described in any one of the above embodiments, including a pure oxygen high efficiency power generation mode operating method, an air high efficiency power generation mode operating method, a wide power generation mode operating method, and an energy storage mode operating method.

[0016] In some embodiments, the pure oxygen high efficiency power generation mode operating method comprises:

[0017] The pure oxygen is mixed with water, preheated by the oxygen multi-stream preheater, and then enters the oxygen electrode of the reversible solid oxide fuel cell, and the hydrocarbon fuel is mixed with water, preheated and reformed by the fuel multi-stream preheater, and then enters the fuel electrode of the reversible solid oxide fuel cell;

[0018] The gases in the oxygen electrode and the fuel electrode generate an electrochemical reaction to discharge electricity, a part of the remaining gases enters the afterburner to burn and generate high temperature flue gas, a part of the remaining gases returns to the fuel storage system after passing through the fuel multi-stream preheater, the water storage system, and the fuel separator, and another part of the remaining gases returns to the oxygen storage system after passing through the oxygen multi-stream preheater, the water storage system, and the oxygen separator;

[0019] The high-temperature flue gas generated by the afterburning chamber is sequentially preheated by the heater, the oxygen multi-stream preheater, or the fuel multi-stream preheater, the multi-stream cooler, and the tail gas separator, and is recovered into the carbon dioxide supply and storage system and the water supply and storage system;

[0020] The closed carbon dioxide cycle subsystem absorbs heat from the heater and releases heat to the multi-stream cooler, and converts heat energy into electric energy by using the compressor, the turbine, and the motor to generate electricity.

[0021] In some embodiments, the air-efficient power generation mode operation method is as follows:

[0022] The ambient atmosphere enters through the oxygen supply and storage system, is preheated by the oxygen multi-stream preheater, and then enters the oxygen electrode of the reversible solid oxide fuel cell; the carbon-hydrogen fuel is mixed with water, is preheated by the fuel multi-stream preheater, and then enters the fuel electrode of the reversible solid oxide fuel cell;

[0023] The gases in the oxygen electrode and the fuel electrode generate an electrochemical reaction to discharge electricity, and the remaining gases enter the afterburning chamber to burn and generate high-temperature flue gas, which is sequentially preheated by the heater, the oxygen multi-stream preheater, or the fuel multi-stream preheater, and is discharged to the atmospheric environment;

[0024] The closed carbon dioxide cycle subsystem absorbs heat from the heater and releases heat to the multi-stream cooler, and converts heat energy into electric energy by using the compressor, the turbine, and the motor to generate electricity.

[0025] In some embodiments, the wide-power generation mode operation method is as follows:

[0026] In the air-efficient power generation mode or the pure-oxygen efficient power generation mode, the fuel provided by the fuel supply and storage system, the oxygen or air of the oxygen supply and storage system, or the circulating flue gas after heat release of the fuel multi-stream preheater or the oxygen multi-stream preheater is mixed and combusted in the afterburning chamber to form high-temperature flue gas, which is sequentially preheated by the afterburning heat exchanger, the oxygen multi-stream preheater, or the fuel multi-stream preheater, and is recovered or discharged to the atmospheric environment; wherein the temperature or flow rate of the carbon dioxide in the closed carbon dioxide cycle subsystem is further increased after absorbing heat from the afterburning heat exchanger, so that the overall power generation of the system is increased.

[0027] In some embodiments, the energy storage mode operation method is as follows:

[0028] The fuel provided by the fuel supply and storage system, the oxygen or air of the oxygen supply and storage system, or the circulating flue gas after heat release of the fuel multi-stream preheater or the oxygen multi-stream preheater is mixed and combusted in the afterburning chamber to form high-temperature flue gas, which preheats the fuel multi-stream preheater, the oxygen multi-stream preheater, and the reversible solid oxide fuel cell;

[0029] The carbon dioxide supply and storage system supplies carbon dioxide, the water supply and storage system supplies water, the water and carbon dioxide are sequentially mixed by a fuel electrode mixer and preheated by a fuel electrode multi-flow preheater, and then enter a fuel electrode of the reversible solid oxide fuel cell; the water supplied by the water supply and storage system is preheated by an oxygen electrode multi-flow preheater, and then enters an oxygen electrode of the reversible solid oxide fuel cell as an oxygen carrier gas;

[0030] The gases in the fuel electrode and the oxygen electrode absorb electric energy to generate electrochemical reactions, oxygen is generated in the oxygen electrode, and hydrocarbon fuel is generated in the fuel electrode; the mixed gas composed of oxygen and water is sequentially preheated by an oxygen electrode multi-flow preheater and a water supply and storage system, and then is discharged, separated by an oxygen separator, and then the recovered oxygen enters an oxygen supply and storage system, the recovered water enters the water supply and storage system; the hydrocarbon fuel mixed gas is sequentially preheated by a fuel electrode multi-flow preheater and a water supply and storage system, and then is discharged, separated by a fuel separator, and then the recovered fuel enters a fuel supply and storage system, and the recovered water enters the water supply and storage system.

[0031] Compared with the prior art, the multifunctional power generation system and method based on the reversible solid oxide fuel cell provided by the application at least has one of the following beneficial effects:

[0032] 1. The multifunctional power generation system based on the reversible solid oxide fuel cell provided by the application deeply couples the reversible solid oxide fuel cell, the closed carbon dioxide cycle and the supercharged combustion cycle, and realizes the functions of high efficiency, wide power variation, trans-medium operation on the water surface and under water independent of air and dependent on air, energy storage and use integration and the like on a complete power generation system.

[0033] 2. The multifunctional power generation system based on the reversible solid oxide fuel cell provided by the application realizes energy cascade utilization by combining the solid oxide fuel cell with the closed carbon dioxide cycle, and improves the power generation efficiency of the system; the power adjustment range of the solid oxide fuel cell is small, and the power variation has a greater influence on the efficiency; the power adjustment range of the closed carbon dioxide cycle is large, and the power variation has a smaller influence on the efficiency, and the combination of the supercharged combustion cycle and the control parameter adjustment can realize the function of wide power adjustment.

[0034] 3. The multifunctional power generation system based on the reversible solid oxide fuel cell provided by the application can use the reversible solid oxide fuel cell cycle subsystem under air and pure oxygen conditions, so that the system has the trans-medium operation capability on the water surface and under water; the system can use oxygen fuel power generation, and can also use electricity to convert carbon dioxide and water into oxygen and fuel, so as to realize the function of energy storage and use integration. BRIEF DESCRIPTION OF DRAWINGS

[0035] The above-mentioned characteristics, technical features, advantages and implementation modes of the application will be further described in the following in a clear and easy-to-understand manner in combination with the preferred embodiments and the accompanying drawings.

[0036] Figure 1is a structural schematic diagram of a multifunctional power generation system based on a reversible solid oxide fuel cell according to a preferred embodiment of the present application;

[0037] Figure 2 is a flow schematic diagram of a pure-oxygen high-efficiency power generation mode according to a preferred embodiment of the present application;

[0038] Figure 3 is a flow schematic diagram of an air high-efficiency power generation mode according to a preferred embodiment of the present application;

[0039] Figure 4 is a flow schematic diagram of a wide-power generation mode according to a preferred embodiment of the present application;

[0040] Figure 5 is a flow schematic diagram of an energy storage mode according to a preferred embodiment of the present application.

[0041] BRIEF DESCRIPTION OF DRAWINGS

[0042] Exhaust gas separator 1, multi-stream cooler 2, oxygen separator 3, fuel supply and storage system 4, water supply and storage system 5, fuel electrode mixer 6, fuel electrode multi-stream preheater 7, reversible solid oxide fuel cell 8, afterburner 9, afterburning combustion chamber 10, carbon dioxide supply and storage system 11, oxygen electrode mixer 12, oxygen electrode multi-stream preheater 13, oxygen supply and storage system 14, fuel separator 15, regenerator 16, heater 17, afterburning combustion heat exchanger 18, compressor 19, turbine 20, motor 21, exhaust gas 22, cooling medium 23, air 24. DETAILED DESCRIPTION

[0043] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the specific embodiments of the present application will be described below with reference to the drawings. Obviously, the drawings in the following description only represent some embodiments of the present application, and those skilled in the art can also obtain other drawings and embodiments according to these drawings without any creative effort.

[0044] In order to make the drawing simple, only the parts related to the present application are shown in each drawing, and they do not represent the actual structure of the product. In addition, in order to make the drawing simple and easy to understand, in some drawings, only one of the components with the same structure or function is shown schematically, or only one of them is marked. In this document, "one" not only means "only one", but also means "more than one" situation.

[0045] It should be further understood that the term "and / or" used in the present application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes these combinations.

[0046] In this article, it is necessary to explain that, unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be connected inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0047] In addition, in the description of the present application, the terms "first", "second" and the like are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0048] In one embodiment, referring to the description attached Figure 1 The multifunctional power generation system based on reversible solid oxide fuel cell provided by the present application comprises a reversible solid oxide fuel cell cycle subsystem, a closed carbon dioxide cycle subsystem and a forced combustion cycle subsystem, the reversible solid oxide fuel cell cycle subsystem is coupled with the closed carbon dioxide cycle subsystem and the forced combustion cycle subsystem respectively, so that the multifunctional power generation system has a pure oxygen high-efficiency power generation mode, an air high-efficiency power generation mode, a wide power generation mode and an energy storage mode; wherein the reversible solid oxide fuel cell cycle subsystem is used for working in the pure oxygen high-efficiency power generation mode, the air high-efficiency power generation mode, the wide power generation mode and the energy storage mode, the closed carbon dioxide cycle subsystem is used for working in the pure oxygen high-efficiency power generation mode, the air high-efficiency power generation mode and the wide power generation mode, and the forced combustion cycle subsystem is used for increasing the power generation power of the system and preheating the system.

[0049] Specifically, referring to the description attached Figure 1 The reversible solid oxide fuel cell cycle subsystem comprises a fuel separator 15, an oxygen separator 3, a tail gas separator 1, a water supply and storage system 5, a carbon dioxide supply and storage system 11, a fuel supply and storage system 4, an oxygen supply and storage system 14, a fuel electrode mixer 6, an oxygen electrode mixer 12, a fuel electrode multi-stream preheater 7, an oxygen electrode multi-stream preheater 13, a multi-stream cooler 2, a reversible solid oxide fuel cell 8, an afterburning chamber 9 and a forced combustion chamber 10.

[0050] The reversible solid oxide fuel cell 8 has a fuel electrode and an oxygen electrode, the fuel electrode is connected with the cold and hot ends of the fuel electrode multi-stream preheater 7 and the afterburning chamber 9 respectively, the oxygen electrode is connected with the cold and hot ends of the oxygen electrode multi-stream preheater 13 and the afterburning chamber 9 respectively, and the afterburning chamber 9 is connected with the hot ends of the oxygen electrode multi-stream preheater 13 and the fuel electrode multi-stream preheater 7 respectively.

[0051] The fuel supply system 4 is connected to the fuel separator 15, the fuel mixer 6 and the afterburner 10, respectively; the oxygen supply system 14 is connected to the oxygen separator 3, the oxygen mixer 12 and the afterburner 10, respectively; the carbon dioxide supply system 11 is connected to the exhaust separator 1 and the fuel mixer 6, respectively; and the water supply system 5 is connected to the fuel mixer 6, the oxygen mixer 12, the fuel separator 15, the oxygen separator 3, the exhaust separator 1, the hot end of the oxygen multi-stream preheater 13 and the hot end of the fuel multi-stream preheater 7, respectively.

[0052] The fuel separator 15 is connected to the oxygen separator 3, the exhaust separator 1 is connected to the multi-stream cooler 2, the oxygen supply system 14 is connected to the atmosphere, and air 24 can be introduced, the multi-stream cooler 2 is connected to the atmosphere, and exhaust 22 can be discharged, and the multi-stream cooler 2 can also be connected to a cooling medium 23, such as cold air or cold water.

[0053] Referring to the accompanying drawings Figure 1 The afterburning cycle subsystem includes the afterburner 10 and the afterburning heat exchanger 18, and the afterburner 10 is connected to the fuel supply system 4, the oxygen supply system 14, the fuel multi-stream preheater 7 and the oxygen multi-stream preheater 13, respectively, and the afterburner 10 is connected to the afterburning heat exchanger 18.

[0054] Referring to the accompanying drawings Figure 1 The closed carbon dioxide cycle subsystem includes the compressor 19, the turbine 20, the regenerator 16, the heater 17 and the motor 21, the hot side inlet of the heater 17 is connected to the afterburner 9, the hot side outlet of the heater 17 is connected to the fuel multi-stream preheater 7 and the oxygen multi-stream preheater 13, respectively, the cold side outlet of the heater 17 is connected to the afterburning heat exchanger 18, the turbine 20 is connected to the afterburning heat exchanger 18, the hot side outlet of the regenerator 16 is connected to the multi-stream cooler 2, and the low pressure inlet and the high pressure outlet of the compressor 19 are connected to the carbon dioxide supply system 11, respectively.

[0055] Further, the multifunctional power generation system based on the reversible solid oxide fuel cell further includes a plurality of control valves, which are arranged in the reversible solid oxide fuel cell cycle subsystem, the closed carbon dioxide cycle subsystem and the afterburning cycle subsystem, respectively, and the control valves are used to control the working states of the components in the subsystems, such as the opening and closing of the components.

[0056] In the embodiment, the reversible solid oxide fuel cell, compressor, turbine, combustion chamber, heat exchanger and other devices are coupled to form a high-efficiency, wide-load, high-power-density, multi-mode, energy storage and utilization integrated "chemical-thermal-electric" high-efficiency conversion composite power cycle. The reversible solid oxide fuel cell, closed carbon dioxide cycle and forced combustion cycle are deeply coupled to realize high efficiency, wide power variation, air-independent and air-dependent water surface and underwater cross-medium operation, energy storage and utilization integration and other functions on a complete power generation system. The solid oxide fuel cell is combined with the closed carbon dioxide cycle to realize energy cascade utilization and improve the system power generation efficiency. The power adjustable range of the solid oxide fuel cell is small, and the power variation has a greater impact on the efficiency. The power adjustable range of the closed carbon dioxide cycle is large, and the power variation has a small impact on the efficiency. The forced combustion cycle and control parameter adjustment can be combined to realize wide power regulation function. The reversible solid oxide fuel cell cycle subsystem can be used under air and pure oxygen conditions, so that the system has the water surface and underwater cross-medium operation capability. Oxygen fuel power generation can be used, and carbon dioxide and water can be converted into oxygen and fuel by using electricity to realize the energy storage and utilization integration function of the system.

[0057] According to another aspect of the present application, the present application further provides a method for operating the multi-functional power generation system based on the reversible solid oxide fuel cell according to any one of the above, including a pure oxygen high-efficiency power generation mode operation method, an air high-efficiency power generation mode operation method, a wide power generation mode operation method and an energy storage mode operation method.

[0058] In one embodiment, reference is made to the description attached Figure 2 The pure oxygen high-efficiency power generation mode operation method is as follows:

[0059] The oxygen and water are mixed, preheated by the oxygen electrode multi-flow preheater 13, and then enter the oxygen electrode of the reversible solid oxide fuel cell 8. The carbon-hydrogen fuel is mixed with water, preheated and reformed by the fuel electrode multi-flow preheater 7, and then enters the fuel electrode of the reversible solid oxide fuel cell 8;

[0060] The gases in the oxygen electrode and the fuel electrode generate an electrochemical reaction to discharge externally, part of the remaining gases enter the afterburning chamber 9 to burn high-temperature flue gas, part of the remaining gases return to the fuel supply and storage system 4 for re-storage after passing through the fuel electrode multi-flow preheater 7, the water supply and storage system 5 and the fuel separator 15, and the other part of the remaining gases return to the oxygen supply and storage system 14 for re-storage after passing through the oxygen electrode multi-flow preheater 13, the water supply and storage system 5 and the oxygen separator 3;

[0061] The high-temperature flue gas generated by the afterburning chamber 9 enters the carbon dioxide supply and storage system 11 and the water supply and storage system 5 after passing through the heater 17, the oxygen electrode multi-flow preheater 13 or the fuel electrode multi-flow preheater 7, the multi-flow cooler 2 and the tail gas separator 1 in sequence;

[0062] The closed carbon dioxide cycle subsystem absorbs heat from the heater 17 and releases heat to the multi-stream cooler 2, and converts heat energy into electricity by using the compressor 19, turbine 20 and motor 21.

[0063] In an embodiment, referring to the attached drawings of the specification Figure 3 , the air-efficient power generation mode operation method is as follows:

[0064] The ambient air enters through the oxygen supply and storage system 14, is preheated by the oxygen electrode multi-stream preheater 13, and then enters the oxygen electrode of the reversible solid oxide fuel cell 8. The hydrocarbon fuel is mixed with water, preheated by the fuel electrode multi-stream preheater 7, and then enters the fuel electrode of the reversible solid oxide fuel cell 8.

[0065] The gases in the oxygen electrode and the fuel electrode generate an electrochemical reaction to discharge electricity, and the remaining gases enter the afterburning chamber 9 to burn and generate high-temperature flue gas. The high-temperature flue gas generated by the afterburning chamber 9 is preheated by the heater 17, the oxygen electrode multi-stream preheater 13, or the fuel electrode multi-stream preheater 7, and then discharged to the atmospheric environment.

[0066] The closed carbon dioxide cycle subsystem absorbs heat from the heater 17 and releases heat to the multi-stream cooler 2, and converts heat energy into electricity by using the compressor 19, turbine 20 and motor 21.

[0067] In an embodiment, referring to the attached drawings of the specification Figure 4 , the wide-power power generation mode operation method is as follows:

[0068] In the air-efficient power generation mode or the pure-oxygen efficient power generation mode, the fuel provided by the fuel supply and storage system 4, the oxygen or air of the oxygen supply and storage system 14, and the circulating flue gas after heat release of the fuel electrode multi-stream preheater 7 or the oxygen electrode multi-stream preheater 13 are mixed and burned in the afterburning chamber 10 to form high-temperature flue gas, which is then recovered or discharged to the atmospheric environment through the afterburning heat exchanger 18, the oxygen electrode multi-stream preheater 13, or the fuel electrode multi-stream preheater 7. The temperature or flow rate of the carbon dioxide in the closed carbon dioxide cycle subsystem is further increased after absorbing heat from the afterburning heat exchanger 18, thereby increasing the overall power generation capacity of the system.

[0069] In an embodiment, referring to the attached drawings of the specification Figure 5 , the energy storage mode operation method is as follows:

[0070] The fuel provided by the fuel supply and storage system 4, the oxygen or air of the oxygen supply and storage system 14, and the circulating flue gas after heat release of the fuel electrode multi-stream preheater 7 or the oxygen electrode multi-stream preheater 13 are mixed and burned in the afterburning chamber 10 to form high-temperature flue gas, which is then used to preheat the fuel electrode multi-stream preheater 7, the oxygen electrode multi-stream preheater 13, and the reversible solid oxide fuel cell 8.

[0071] The carbon dioxide supply and storage system 11 supplies carbon dioxide, the water supply and storage system 5 supplies water, the water and carbon dioxide are mixed in the fuel electrode mixer 6 in turn, and then preheated by the fuel electrode multi-flow preheater 7, and then enter the fuel electrode of the reversible solid oxide fuel cell 8, the water supplied by the water supply and storage system 5 is preheated by the oxygen electrode multi-flow preheater 13, and then enters the oxygen electrode of the reversible solid oxide fuel cell 8 as an oxygen carrier gas;

[0072] The gases in the fuel electrode and the oxygen electrode absorb electric energy to generate electrochemical reactions, oxygen is generated in the oxygen electrode, and hydrocarbon fuel is generated in the fuel electrode, the mixed gas composed of oxygen and water is discharged in turn by the oxygen electrode multi-flow preheater 13 and the water supply and storage system 5, separated by the oxygen separator 3, and then the oxygen is recovered into the oxygen supply and storage system 14, the water is recovered into the water supply and storage system 5, the hydrocarbon fuel mixed gas is discharged in turn by the fuel electrode multi-flow preheater 7 and the water supply and storage system 5, separated by the fuel separator 15, and then the fuel is recovered into the fuel supply and storage system 4, and the water is recovered into the water supply and storage system 5.

[0073] In the above embodiments, the description of each embodiment has its own emphasis, and the parts not described or recorded in detail in a certain embodiment can be referred to the related description of other embodiments.

[0074] It should be noted that the above embodiments can be freely combined as needed. The above are only preferred embodiments of the present application, and it should be pointed out that for ordinary skilled in the art, without departing from the principles of the present application, a number of improvements and refinements can also be made, which should be considered as the protection scope of the present application.

Claims

1. A multifunctional power generation system based on a reversible solid oxide fuel cell, characterized by, The multi-functional power generation system based on reversible solid oxide fuel cell includes a reversible solid oxide fuel cell cycle subsystem, a closed carbon dioxide cycle subsystem and a forced combustion cycle subsystem, the reversible solid oxide fuel cell cycle subsystem is coupled with the closed carbon dioxide cycle subsystem and the forced combustion cycle subsystem respectively, so that the multi-functional power generation system has a pure oxygen high efficiency power generation mode, an air high efficiency power generation mode, a wide power generation mode and an energy storage mode; wherein the reversible solid oxide fuel cell cycle subsystem is used for working in the pure oxygen high efficiency power generation mode, the air high efficiency power generation mode, the wide power generation mode and the energy storage mode, the closed carbon dioxide cycle subsystem is used for working in the pure oxygen high efficiency power generation mode, the air high efficiency power generation mode and the wide power generation mode, and the forced combustion cycle subsystem is used for increasing the power generation power of the system and preheating the system.

2. The multi-functional power generation system based on reversible solid oxide fuel cell according to claim 1, wherein the reversible solid oxide fuel cell cycle subsystem includes a fuel separator, an oxygen separator, a tail gas separator, a water supply and storage system, a carbon dioxide supply and storage system, a fuel supply and storage system, an oxygen supply and storage system, a fuel electrode mixer, an oxygen electrode mixer, a fuel electrode multi-flow preheater, an oxygen electrode multi-flow preheater, a multi-flow cooler, a reversible solid oxide fuel cell, an afterburning chamber and a forced combustion chamber; the reversible solid oxide fuel cell has a fuel electrode and an oxygen electrode, the fuel electrode is connected with cold and hot ends of the fuel electrode multi-flow preheater and the afterburning chamber respectively, the oxygen electrode is connected with cold and hot ends of the oxygen electrode multi-flow preheater and the afterburning chamber respectively, and the afterburning chamber is connected with hot ends of the oxygen electrode multi-flow preheater and the fuel electrode multi-flow preheater respectively; the fuel supply and storage system is connected with the fuel separator, the fuel electrode mixer and the forced combustion chamber respectively, the oxygen supply and storage system is connected with the oxygen separator, the oxygen electrode mixer and the forced combustion chamber respectively, the carbon dioxide supply and storage system is connected with the fuel electrode mixer and the fuel separator respectively, and the water supply and storage system is connected with the fuel electrode mixer, the oxygen electrode mixer, the fuel separator, the oxygen separator, the tail gas separator, a hot end of the oxygen electrode multi-flow preheater and a hot end of the fuel electrode multi-flow preheater respectively; the fuel separator is connected with the oxygen separator, the tail gas separator is connected with the multi-flow cooler, the oxygen supply and storage system is connected with an atmospheric environment, and the multi-flow cooler is connected with the atmospheric environment.

3. The multi-functional power generation system based on reversible solid oxide fuel cell according to claim 2, wherein the forced combustion cycle subsystem includes a forced combustion chamber and a forced combustion heat exchanger, the forced combustion chamber is connected with the fuel supply and storage system, the oxygen supply and storage system, the fuel electrode multi-flow preheater and the oxygen electrode multi-flow preheater respectively, and the forced combustion chamber is connected with the forced combustion heat exchanger.

4. The multi-functional power generation system based on reversible solid oxide fuel cell according to claim 3, wherein ​ ​ ​ ​ ​ The closed carbon dioxide cycle subsystem comprises a compressor, a turbine, a regenerator, a heater and a motor, a hot side inlet of the heater is connected with the afterburning chamber, hot side outlets of the heater are connected with the fuel multi-stream preheater and the oxygen multi-stream preheater respectively, a cold side outlet of the heater is connected with the afterburning heat exchanger, the turbine is connected with the afterburning heat exchanger, a hot side outlet of the regenerator is connected with the multi-stream cooler, and low-pressure inlets and high-pressure outlets of the compressor are connected with the carbon dioxide supply and storage system respectively.

5. The multifunctional power generating system based on reversible solid oxide fuel cell according to claim 4, characterized by, Further comprising: a plurality of control valves arranged in the reversible solid oxide fuel cell cycle subsystem, the closed carbon dioxide cycle subsystem and the afterburning cycle subsystem respectively, the control valves being used for controlling working states of components in the subsystems.

6. A method for operating a multifunctional power generation system based on a reversible solid oxide fuel cell as claimed in any one of claims 1 to 5, characterized by, The method comprises a pure-oxygen high-efficiency power generation mode operation method, an air high-efficiency power generation mode operation method, a wide-power power generation mode operation method and an energy storage mode operation method.

7. The operation method of the reversible solid oxide fuel cell-based multifunctional power generation system according to claim 6, wherein the pure-oxygen high-efficiency power generation mode operation method is as follows: pure oxygen is mixed with water, preheated by the oxygen multi-stream preheater and then enters the oxygen electrode of the reversible solid oxide fuel cell, and hydrocarbon fuel is mixed with water, preheated and reformed by the fuel multi-stream preheater and then enters the fuel electrode of the reversible solid oxide fuel cell; gases in the oxygen electrode and the fuel electrode generate electrochemical reactions to discharge to the outside, part of the remaining gases enters the afterburning chamber to burn to generate high-temperature flue gas, part of the remaining gases passes through the fuel multi-stream preheater, the water supply and storage system and the fuel separator and then returns to the fuel supply and storage system to be stored again, and part of the remaining gases passes through the oxygen multi-stream preheater, the water supply and storage system and the oxygen separator and then returns to the oxygen supply and storage system to be stored again; the high-temperature flue gas generated by the afterburning chamber is sequentially preheated by the heater, the oxygen multi-stream preheater or the fuel multi-stream preheater, the multi-stream cooler and the tail gas separator, and then is recovered into the carbon dioxide supply and storage system and the water supply and storage system; the closed carbon dioxide cycle subsystem absorbs heat from the heater, releases heat to the multi-stream cooler, and converts heat energy into electric energy by the compressor, the turbine and the motor to generate power to the outside.

8. The operation method of the reversible solid oxide fuel cell-based multifunctional power generation system according to claim 6, wherein the air high-efficiency power generation mode operation method is as follows: ambient air enters through the oxygen supply and storage system, is preheated by the oxygen multi-stream preheater and then enters the oxygen electrode of the reversible solid oxide fuel cell, and hydrocarbon fuel is mixed with water, preheated and reformed by the fuel multi-stream preheater and then enters the fuel electrode of the reversible solid oxide fuel cell; gases in the oxygen electrode and the fuel electrode generate electrochemical reactions to discharge to the outside, and the remaining gases enter the afterburning chamber to burn to generate high-temperature flue gas, and the high-temperature flue gas generated by the afterburning chamber is sequentially preheated by the heater, the oxygen multi-stream preheater or the fuel multi-stream preheater and then is discharged to the ambient environment; The closed carbon dioxide cycle subsystem absorbs heat from the heater and releases heat to the multi-stream cooler, and converts heat energy into electricity by using the compressor, turbine and motor.

9. The method for operating the multi-functional power generation system based on the reversible solid oxide fuel cell according to claim 7 or 8, characterized in that, The wide power generation mode operating method is: In the air efficient power generation mode or the pure oxygen efficient power generation mode, the fuel provided by the fuel supply and storage system, the oxygen or air provided by the oxygen supply and storage system, or the circulating flue gas after the heat release of the fuel multi-stream preheater or the oxygen multi-stream preheater is mixed and burned in the afterburner to form high-temperature flue gas, which is sequentially passed through the afterburner heat exchanger, the oxygen multi-stream preheater or the fuel multi-stream preheater, and then recovered or discharged to the atmosphere; wherein the temperature or flow rate of the carbon dioxide in the closed carbon dioxide cycle subsystem is further increased after absorbing heat from the afterburner heat exchanger, so that the overall power generation power of the system is increased.

10. The method for operating the multi-functional power generation system based on the reversible solid oxide fuel cell according to claim 6, characterized in that, The energy storage mode operating method is: The fuel provided by the fuel supply and storage system, the oxygen or air provided by the oxygen supply and storage system, or the circulating flue gas after the heat release of the fuel multi-stream preheater or the oxygen multi-stream preheater is mixed and burned in the afterburner to form high-temperature flue gas, which preheats the fuel multi-stream preheater, the oxygen multi-stream preheater, and the reversible solid oxide fuel cell; The carbon dioxide supply and storage system provides carbon dioxide, and the water supply and storage system provides water. The water and carbon dioxide are sequentially mixed in the fuel mixing device and preheated in the fuel multi-stream preheater, and then enter the fuel electrode of the reversible solid oxide fuel cell. The water supply and storage system provides water, which is preheated in the oxygen multi-stream preheater and then enters the oxygen electrode of the reversible solid oxide fuel cell as an oxygen carrier gas. The gases in the fuel electrode and the oxygen electrode absorb electric energy to generate electrochemical reactions, oxygen is generated in the oxygen electrode, and carbon-hydrogen fuel is generated in the fuel electrode. The mixed gas composed of oxygen and water is sequentially released in the oxygen multi-stream preheater and the water supply and storage system, separated by the oxygen separator, and then the oxygen is recovered into the oxygen supply and storage system, the water is recovered into the water supply and storage system, the carbon-hydrogen fuel mixed gas is sequentially released in the fuel multi-stream preheater and the water supply and storage system, separated by the fuel separator, and then the fuel is recovered into the fuel supply and storage system, and the water is recovered into the water supply and storage system.

Images