A combined power generation system

Abstract

This invention provides a composite power generation system, comprising a first power generation unit and a second power generation unit. The first power generation unit includes a gas turbine, a first generator, and a waste heat boiler. The first output terminal of the gas turbine is connected to the first generator, and the second output terminal is connected to the waste heat boiler. The gas turbine and the first generator cooperate to convert the chemical energy of the gas into electrical energy and transmit it to the power grid. Simultaneously, the exhaust gas from the gas turbine enters the waste heat boiler. The second power generation unit includes an electrolytic cell, a solid oxide fuel cell, a first gas storage tank, and a second gas storage tank. The electrolytic cell is connected to the waste heat boiler. The input terminals of the first and second gas storage tanks are respectively connected to the electrolytic cell, and their output terminals are respectively connected to the solid oxide fuel cell. One technical advantage of this invention is its rational design, which enables the generation of electricity using renewable energy while improving the peak-shaving and frequency regulation capabilities of the power generation system.

Description

Technical Field

[0001] This invention belongs to the field of composite power generation technology, and specifically relates to a composite power generation system. Background Technology

[0002] In recent years, the installed capacity of new energy has been increasing year by year. However, due to the volatility and intermittency of renewable energy, thermal power generating units need to improve their load adjustment flexibility in order to undertake the peak shaving work of the power grid.

[0003] Currently, gas turbine power generation is usually combined with waste heat boilers to form a high-efficiency power generation mode of gas-steam combined cycle. However, this power generation mode often adopts the "heat-driven power generation" operation mode, which is constrained by the strong thermoelectric coupling characteristics, resulting in a significant reduction in the peak-shaving and frequency regulation capabilities of the power generation system.

[0004] Therefore, there is an urgent need for a hybrid power generation system that can both utilize renewable energy to generate electricity and improve the peak shaving and frequency regulation capabilities of the power generation system. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art and provide a new technical solution for a composite power generation system.

[0006] According to one aspect of the present invention, a hybrid power generation system is provided, comprising:

[0007] The first power generation unit includes a gas turbine, a first generator, and a waste heat boiler; the first output end of the gas turbine is connected to the first generator, and the second output end is connected to the waste heat boiler; the gas turbine and the first generator cooperate to convert the chemical energy of the gas into electrical energy and transmit it to the power grid, while the exhaust gas of the gas turbine enters the waste heat boiler.

[0008] The second power generation unit includes an electrolytic cell, a solid oxide fuel cell, a first gas storage tank, and a second gas storage tank; the electrolytic cell is connected to the waste heat boiler; the input ends of the first gas storage tank and the second gas storage tank are respectively connected to the electrolytic cell, and the output ends are respectively connected to the solid oxide fuel cell.

[0009] The exhaust gas from the waste heat boiler enters the electrolytic cell, which is used to electrolyze the electricity generated from renewable energy and produce H2, CO, air and O2 under the action of the exhaust gas from the waste heat boiler and air. The H2 and CO are stored in the first gas storage tank, and the air and O2 are stored in the second gas storage tank.

[0010] When H2 and CO from the first gas storage tank are delivered to the fuel electrode of the solid oxide fuel cell, and air and O2 are delivered to the air electrode of the solid oxide fuel cell, the electrical energy generated by the electrolysis reaction in the solid oxide fuel cell is delivered to the power grid to increase the load on the power grid.

[0011] Optionally, the composite power generation system further includes a third power generation unit, which includes a steam turbine, a second generator, and a condenser; the input end of the steam turbine is connected to the waste heat boiler, the first output end is connected to the second generator, the second output end is connected to the condenser, and the output end of the condenser is connected to the waste heat boiler.

[0012] Optionally, the electrolytic cell includes a fuel electrode and an air electrode, the fuel electrode being connected to a waste heat boiler; the exhaust gas from the waste heat boiler is supplied to the fuel electrode, and air is input to the air electrode; wherein the exhaust gas from the waste heat boiler includes CO2 and H2O.

[0013] Optionally, it also includes a first delivery pipe and a first circulation pipe;

[0014] One end of the first delivery pipe is connected to the waste heat boiler, and the other end is connected to the fuel electrode; one end of the second delivery pipe is connected to the solid oxide fuel cell, and the other end is connected to the first delivery pipe.

[0015] The CO2 and H2O generated during the electrolysis process of the solid oxide fuel cell are fed into the first delivery pipe and mixed with the CO2 and H2O in the first delivery pipe before entering the fuel electrode.

[0016] Optionally, it also includes a third gas storage tank, which is disposed on the side of the first delivery pipe near the fuel electrode.

[0017] Optionally, the fuel electrode is made of ruthenium-based or cerium-based materials.

[0018] Optionally, the air electrode is made of ruthenium-based or cerium-based materials.

[0019] Optionally, the renewable energy source includes solar energy.

[0020] Optionally, the renewable energy source includes wind power.

[0021] Optionally, the renewable energy source includes hydropower.

[0022] One technical advantage of this invention is that:

[0023] In this embodiment, the exhaust gas from a waste heat boiler and air are used to electrolyze the unstable electrical energy generated from renewable energy sources to produce H2, CO, and O2, which are then stored in a first and a second gas storage tank. When the power grid requires high load operation, the electrical energy generated by the electrolysis reaction in the solid oxide fuel cell is supplied to the power grid to increase the grid load by supplying H2 and CO from the first gas storage tank to the fuel electrode of the solid oxide fuel cell and supplying air and O2 to the air electrode of the solid oxide fuel cell.

[0024] Therefore, this composite power generation system is reasonably designed, as it can both utilize renewable energy to generate electricity and improve the peak shaving and frequency regulation capabilities of the power generation system. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of a composite power generation system according to an embodiment of the present invention.

[0026] In the diagram: 11. Gas turbine; 12. First generator; 13. Waste heat boiler; 21. Electrolyte cell; 22. Solid oxide fuel cell; 23. First gas storage tank; 24. Second gas storage tank; 31. Steam turbine; 32. Second generator; 33. Condenser; 4. First delivery pipe; 5. First circulation pipe; 6. Third gas storage tank; 7. Renewable energy. Detailed Implementation

[0027] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the present application.

[0028] The embodiments of this application will now be described in detail. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0029] The terms "first" and "second" in the specification and claims of this application may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise stated, "multiple" means two or more. Furthermore, "and / or" in the specification and claims indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0030] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0031] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0032] See Figure 1 According to one aspect of the present invention, a hybrid power generation system is provided, comprising:

[0033] The first power generation unit includes a gas turbine 11, a first generator 12, and a waste heat boiler 13. The first output end of the gas turbine 11 is connected to the first generator 12, and the second output end is connected to the waste heat boiler 13. The gas turbine 11 and the first generator 12 cooperate to convert the chemical energy of the gas into electrical energy and transmit it to the power grid. At the same time, the exhaust gas of the gas turbine 11 enters the waste heat boiler 13.

[0034] The second power generation unit includes an electrolytic cell 21, a solid oxide fuel cell 22, a first gas storage tank 23, and a second gas storage tank 24. The electrolytic cell 21 is connected to the waste heat boiler 13. The input terminals of the first gas storage tank 23 and the second gas storage tank 24 are respectively connected to the electrolytic cell 21, and the output terminals are respectively connected to the solid oxide fuel cell 22.

[0035] The exhaust gas from the waste heat boiler 13 enters the electrolytic cell 21. The electrolytic cell 21 is used to electrolyze the electrical energy generated by the renewable energy 7 under the action of the exhaust gas from the waste heat boiler 13 and air to generate H2, CO, air and O2. The H2 and CO are stored in the first gas storage tank 23, and the air and O2 are stored in the second gas storage tank 24. The exhaust gas from the waste heat boiler 13 includes CO2 and H2O, where H2O refers to water vapor.

[0036] When H2 and CO from the first gas storage tank 23 are delivered to the fuel electrode of the solid oxide fuel cell 22, and air and O2 are delivered to the air electrode of the solid oxide fuel cell 22, the electrical energy generated by the electrolysis reaction in the solid oxide fuel cell 22 is delivered to the power grid to increase the load on the power grid.

[0037] In this embodiment, the exhaust gas from the waste heat boiler 13 and air are used to electrolyze the unstable electrical energy generated by the renewable energy source 7 to produce H2, CO, and O2, which are then stored in the first gas storage tank 23 and the second gas storage tank 24. When the power grid requires high load operation, the electrical energy generated by the electrolysis reaction in the solid oxide fuel cell 22 is supplied to the power grid to increase the grid load by supplying H2 and CO from the first gas storage tank 23 to the fuel electrode of the solid oxide fuel cell 22 and supplying air and O2 to the air electrode of the solid oxide fuel cell 22.

[0038] Therefore, the design of this composite power generation system is reasonable, as it can both generate electricity using renewable energy and improve the peak shaving and frequency regulation capabilities of the power generation system.

[0039] It should be noted that, due to the fluctuating and intermittent nature of electricity generated from renewable energy sources, it is difficult for the power grid to fully utilize it. However, the reversible solid oxide fuel cell (rSOC) of this application features an electrolysis efficiency that does not change with power output, thus meeting the power grid's demand. The reversible solid oxide fuel cell (rSOC) comprises a fuel cell (SOFC) and an electrolyzer (SOEC), and has two operating modes: chemical energy storage mode and electrolysis power generation mode. The fuel cell is the solid oxide fuel cell described in this application. The hybrid power generation system of this application captures the exhaust gas emitted from fossil fuel combustion (i.e., exhaust gas from a waste heat boiler) through the SOEC and stores the electricity generated from renewable energy in the form of chemical energy (i.e., fuel). Then, when the power grid needs it, the stored fuel is used to generate electricity through the SOFC to increase the grid load, thereby meeting the grid's peak shaving and frequency regulation requirements.

[0040] Optionally, the composite power generation system further includes a third power generation unit, which includes a steam turbine 31, a second generator 32, and a condenser 33; the input end of the steam turbine 31 is connected to the waste heat boiler 13, the first output end is connected to the second generator 32, the second output end is connected to the condenser 33, and the output end of the condenser 33 is connected to the waste heat boiler 13.

[0041] In the above embodiment, the unstable electrical energy generated by renewable energy 7 can be electrolyzed to produce H2, CO, air, and O2. H2 and CO are stored in the first gas storage tank 23, and air and O2 are stored in the second gas storage tank 24. During the gas-steam coupled power generation process, when the power grid needs to increase its load, it is only necessary to transport H2 and CO from the first gas storage tank 23 to the fuel electrode of the solid oxide fuel cell 22, and transport air and O2 to the air electrode of the solid oxide fuel cell 22. The electrical energy generated by the electrolysis reaction in the solid oxide fuel cell 22 is then supplied to the power grid to increase the grid load. The operation is simple and can further meet the peak shaving and frequency regulation requirements of the hybrid power generation system.

[0042] Optionally, the electrolytic cell 21 includes a fuel electrode and an air electrode, the fuel electrode being connected to the waste heat boiler 13; the exhaust gas from the waste heat boiler 13 is supplied to the fuel electrode, and air is input to the air electrode; wherein the exhaust gas from the waste heat boiler 13 includes CO2 and H2O.

[0043] In the above embodiments, the exhaust gas generated by the waste heat boiler 13 can be fully utilized, and the chemical energy formed by electrolyzing the unstable electrical energy generated by the renewable energy 7 can be stably stored. When the power grid needs peak shaving and frequency regulation, the stored chemical energy can be used to generate electrical energy in the solid oxide fuel cell 22 to improve the peak shaving and frequency regulation capability of the power grid.

[0044] Optionally, it also includes a first delivery pipe 4 and a first circulation pipe 5;

[0045] One end of the first delivery pipe 4 is connected to the waste heat boiler 13, and the other end is connected to the fuel electrode; one end of the second delivery pipe is connected to the solid oxide fuel cell 22, and the other end is connected to the first delivery pipe 4.

[0046] The CO2 and H2O generated during the electrolysis process of the solid oxide fuel cell 22 are fed into the first delivery pipe 4 and mixed with the CO2 and H2O in the first delivery pipe 4 before entering the fuel electrode. Here, H2O refers to water vapor.

[0047] In the above embodiments, the heat energy, CO2 and H2O generated during the electrolysis process can be recycled, which helps to achieve energy conservation and emission reduction on the one hand, and helps to ensure the stable operation of the electrolysis process in the electrolytic cell 21 on the other hand.

[0048] Optionally, a third gas storage tank 6 is also included, which is disposed on the side of the first delivery pipe 4 near the fuel electrode. The third gas storage tank 6 is used to store CO2 and H2O and supply them to the electrolytic cell 21 as needed, thereby better meeting the electrolysis requirements of the electrolytic cell 21 and improving the electrolysis efficiency of the electrolytic cell 21.

[0049] Optionally, the fuel electrode is made of ruthenium-based or cerium-based materials.

[0050] Optionally, the air electrode is made of ruthenium-based or cerium-based materials.

[0051] In the above embodiments, since ruthenium-based materials or cerium-based materials are both materials with high resistance to carbon deposition, they can meet the functional requirements of electrolytic cell 21 and help ensure the stability of the electrolysis process of electrolytic cell 21.

[0052] Optionally, the renewable energy source 7 includes solar energy. This enables the hybrid power generation system to make full use of unstable solar energy, significantly improving its peak-shaving and frequency regulation capabilities.

[0053] Optionally, the renewable energy source 7 includes wind power. This enables the hybrid power generation system to make full use of unstable wind energy, significantly improving the peak shaving and frequency regulation capabilities of the hybrid power generation system.

[0054] Optionally, the renewable energy source 7 includes hydropower. This allows the hybrid power generation system to fully utilize unstable hydropower resources, significantly improving its peak-shaving and frequency regulation capabilities.

[0055] It is understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A composite power generation system, characterized in that, include: The first power generation unit includes a gas turbine, a first generator, and a waste heat boiler; the first output end of the gas turbine is connected to the first generator, and the second output end is connected to the waste heat boiler; the gas turbine and the first generator cooperate to convert the chemical energy of the gas into electrical energy and transmit it to the power grid, while the exhaust gas of the gas turbine enters the waste heat boiler. The second power generation unit includes an electrolytic cell, a solid oxide fuel cell, a first gas storage tank, and a second gas storage tank; the electrolytic cell is connected to the waste heat boiler; the input ends of the first gas storage tank and the second gas storage tank are respectively connected to the electrolytic cell, and the output ends are respectively connected to the solid oxide fuel cell. The exhaust gas from the waste heat boiler enters the electrolytic cell, which is used to electrolyze the electricity generated from renewable energy and produce H2, CO, air and O2 under the action of the exhaust gas from the waste heat boiler and air. The H2 and CO are stored in the first gas storage tank, and the air and O2 are stored in the second gas storage tank. When H2 and CO from the first gas storage tank are delivered to the fuel electrode of the solid oxide fuel cell, and air and O2 are delivered to the air electrode of the solid oxide fuel cell, the electrical energy generated by the electrolysis reaction in the solid oxide fuel cell is delivered to the power grid to increase the load on the power grid. The electrolytic cell includes a fuel electrode and an air electrode, the fuel electrode being connected to a waste heat boiler; the exhaust gas from the waste heat boiler is supplied to the fuel electrode, and air is input to the air electrode; wherein, the exhaust gas from the waste heat boiler includes CO2 and H2O.

2. The composite power generation system according to claim 1, characterized in that, It also includes a third power generation unit, which includes a steam turbine, a second generator, and a condenser; the input end of the steam turbine is connected to the waste heat boiler, the first output end is connected to the second generator, the second output end is connected to the condenser, and the output end of the condenser is connected to the waste heat boiler.

3. The composite power generation system according to claim 1, characterized in that, It also includes a first delivery pipe and a first circulation pipe; One end of the first delivery pipe is connected to the waste heat boiler, and the other end is connected to the fuel electrode; one end of the first circulation pipe is connected to the solid oxide fuel cell, and the other end is connected to the first delivery pipe. The CO2 and H2O generated during the electrolysis process of the solid oxide fuel cell are fed into the first delivery pipe and mixed with the CO2 and H2O in the first delivery pipe before entering the fuel electrode.

4. The composite power generation system according to claim 3, characterized in that, It also includes a third gas storage tank, which is located on the side of the first delivery pipe near the fuel electrode.

5. The composite power generation system according to claim 4, characterized in that, The fuel electrode is made of ruthenium-based or cerium-based materials.

6. The composite power generation system according to claim 4, characterized in that, The air electrode is made of ruthenium-based or cerium-based materials.

7. The composite power generation system according to claim 1, characterized in that, The renewable energy source includes solar energy.

8. The composite power generation system according to claim 1, characterized in that, The renewable energy sources include wind power.

9. The composite power generation system according to claim 1, characterized in that, The renewable energy sources include hydropower.

Images