Ammonia and hydrogen blending power generation system and method for thermal cycle and exhaust gas treatment in gas-fired power plants

Abstract

The application provides a kind of ammonia-doped hydrogen-doped power generation system and method for thermal cycle and tail gas treatment of gas power plant, and relates to the field of new energy technology, by combining the advantages and disadvantages of ammonia hydrogen new energy utilization, it can utilize the advantage of easy storage and transportation of liquid ammonia, supply large-scale hydrogen for hydrogen-doped combustion of gas power plant on site, or directly supply ammonia combustion power generation, at the same time, the technology can utilize the waste heat of gas turbine, and carry out tail gas denitration treatment, which can reduce carbon and nitrogen while recovering waste heat, improve the cycle thermal efficiency, and achieve the purpose of energy saving and emission reduction. Since there is no carbon dioxide emission after hydrogen and ammonia combustion, gradually increasing the proportion of ammonia-doped and hydrogen-doped combustion can reduce carbon emission of power plant; using waste heat of gas power plant to vaporize liquid ammonia and providing heat energy for ammonia decomposition can reduce carbon while recovering waste heat, improving the cycle thermal efficiency; using liquid ammonia for tail gas denitration treatment can reduce the concentration of nitrogen oxides in flue gas to standard level, realizing the comprehensive utilization of liquid ammonia.

Description

Technical Field

[0001] This invention relates to the field of new energy technology, and in particular to an ammonia- and hydrogen-blended power generation system and method for thermal cycle and exhaust gas treatment in gas-fired power plants. Background Technology

[0002] Currently, domestic gas-fired power plants commonly use gas-steam combined cycle units to generate electricity from natural gas combustion. These units include gas turbines, waste heat boilers, and steam turbines. The basic principle is that the high-temperature gas produced by natural gas combustion first drives a gas turbine to perform work, which in turn drives a coaxial generator for the first stage of power generation. Then, the high-temperature combustion gas discharged from the gas turbine is sent to a waste heat steam generator, where the generated high-temperature, high-pressure steam drives a steam turbine for the second stage of power generation. However, natural gas combustion produces a large amount of carbon dioxide, and the gas turbine combustion also produces nitrogen oxides. If a waste heat boiler is used for supplementary combustion, nitrogen oxide emissions will increase, making it impossible to solve the carbon and nitrogen emission problems.

[0003] Most global gas turbine equipment manufacturers design conventional combustion systems for natural gas that can accommodate a low proportion of hydrogen fuel. Currently, hydrogen is mainly sourced through pipeline transportation and hydrogen long-tube trailers.

[0004] Hydrogen pipeline transportation typically has a capacity of 310-8900 kg / h, but the initial investment is high. Due to hydrogen's low volumetric energy density and susceptibility to "hydrogen embrittlement" in pipeline materials, its transportation cost is often more than twice that of natural gas pipeline transportation at the same energy flow rate. Globally, the total number of hydrogen pipelines is less than 4500 kilometers, several orders of magnitude less than that of oil and gas pipelines. Currently, low-pressure hydrogen pipeline transportation is still in its early stages of development both domestically and internationally, and it is unlikely that a dedicated hydrogen pipeline will be built for a specific gas-fired power plant.

[0005] Hydrogen long-tube trailer transportation technology is relatively mature, but each vehicle can only transport 250-460 kg, which is small and not suitable for long-distance transportation, nor is it suitable for large-scale use in gas-fired power plants with hydrogen blending.

[0006] The production of hydrogen from ammonia fuel also faces some problems, especially the decomposition which requires a lot of energy. For example, the vaporization of liquid ammonia requires external heating, and complete decomposition requires a temperature of over 550°C. The whole process requires a high amount of energy. Summary of the Invention

[0007] This invention provides an ammonia- and hydrogen-blended power generation system for gas-fired power plant thermal cycle and exhaust gas treatment, which solves the problems of inconvenient hydrogen transportation and carbon emissions in the prior art.

[0008] This invention provides an ammonia-hydrogen blending power generation system for a gas-fired power plant's thermal cycle and exhaust gas treatment, comprising a liquid ammonia storage device, a liquid ammonia pump, a vaporizer, a mixing device, a denitrification reactor, an ammonia decomposition reactor, an ammonia removal tower, a hydrogen extraction tower, a natural gas supply device, a natural gas-hydrogen mixer, a natural gas-ammonia mixer, a hydrogen-blending power generation turbine, and an ammonia-blending power generation turbine. The outlet of the liquid ammonia storage device is connected to the first end of a first pipeline. The liquid ammonia pump, the vaporizer, and the mixing device are sequentially connected in series on the first pipeline. The second end of the first pipeline is connected to the first inlet of the denitrification reactor. The first outlet of the ammonia decomposition reactor is connected to the second inlet of the denitrification reactor via a second pipeline. The inlet of the ammonia decomposition reactor is connected to the first pipeline between the vaporizer and the mixing device via a third pipeline. The second outlet of the ammonia decomposition reactor is connected to the first end of a fourth pipeline. The ammonia removal tower, the hydrogen extraction tower, and the natural gas-hydrogen mixer are connected in series on the fourth pipeline. The inlet of the hydrogen-blended power generation turbine is connected to the second end of the fourth pipeline. The inlet of the ammonia-blended power generation turbine is connected to the third pipeline via a fifth pipeline. The natural gas-ammonia mixer is connected in series on the fifth pipeline. The first outlet of the natural gas supply device is connected to the fourth pipeline, and the second outlet of the natural gas supply device is connected to the fifth pipeline.

[0009] According to an embodiment of the present invention, a gas-fired power plant thermal cycle and exhaust gas treatment ammonia-hydrogen blending power generation system is provided, wherein the blending device includes:

[0010] An air-ammonia mixer is connected in series on the first pipeline between the vaporizer and the denitrification reactor;

[0011] The first fan has its outlet connected to the air inlet of the air-ammonia mixer, which is used to mix the input ammonia gas with the air delivered by the first fan.

[0012] According to an embodiment of the present invention, a gas-fired power plant thermal cycle and exhaust gas treatment ammonia- and hydrogen-blended power generation system further includes:

[0013] A buffer tank is connected in series on the first pipeline between the vaporizer and the air-ammonia mixer.

[0014] According to an embodiment of the present invention, a gas-fired power plant thermal cycle and exhaust gas treatment ammonia- and hydrogen-blended power generation system further includes:

[0015] The second fan is connected in series on the first pipeline between the air-ammonia mixer and the denitrification reactor.

[0016] According to an embodiment of the present invention, a gas-fired power plant thermal cycle and exhaust gas treatment ammonia- and hydrogen-blended power generation system further includes:

[0017] A cooler is connected in series on the fourth pipeline between the ammonia decomposition reactor and the deammoniation tower. The cooler is used to cool the mixture of hydrogen and nitrogen output from the ammonia decomposition reactor.

[0018] According to an embodiment of the present invention, a gas-fired power plant thermal cycle and exhaust gas treatment ammonia- and hydrogen-blended power generation system further includes:

[0019] A hydrogen compressor is connected in series in the fourth pipeline between the hydrogen extraction tower and the natural gas-hydrogen mixer. The hydrogen compressor is used to increase the hydrogen pressure output by the hydrogen extraction tower.

[0020] According to an embodiment of the present invention, a gas-fired power plant thermal cycle and exhaust gas treatment ammonia- and hydrogen-blended power generation system further includes:

[0021] An ammonia compressor is connected in series with the fifth pipeline between the third pipeline and the natural gas-ammonia mixer. The ammonia compressor is used to increase the ammonia pressure input to the third pipeline.

[0022] According to an embodiment of the present invention, a gas-fired power plant thermal cycle and exhaust gas treatment ammonia- and hydrogen-blended power generation system further includes:

[0023] A first regulating valve is installed in the third pipeline;

[0024] The second regulating valve is located in the third pipeline between the first regulating valve and the ammonia decomposition reactor;

[0025] The third regulating valve is located in the fifth pipeline between the ammonia compressor and the third pipeline.

[0026] According to an embodiment of the present invention, a gas-fired power plant thermal cycle and exhaust gas treatment ammonia- and hydrogen-blended power generation system further includes:

[0027] The fourth regulating valve is located in the fourth pipeline between the hydrogen compressor and the natural gas-hydrogen mixer;

[0028] The fifth regulating valve is located at the first gas outlet of the natural gas supply device;

[0029] The sixth regulating valve is located at the second gas outlet of the natural gas supply device.

[0030] The present invention also provides a method for ammonia- and hydrogen-blended power generation involving the thermal cycle and exhaust gas treatment of a gas-fired power plant, the method being based on the ammonia- and hydrogen-blended power generation system for the thermal cycle and exhaust gas treatment of a gas-fired power plant as described in any of the above claims, comprising:

[0031] The liquid ammonia pump pumps the liquid ammonia from the liquid ammonia storage device to the vaporizer for vaporization;

[0032] The gasified ammonia is divided into three streams. The first stream of ammonia enters a mixing device to mix with air. The mixed gas then enters a denitrification reactor to react with the flue gas input from the ammonia decomposition reactor to remove nitrogen oxides from the flue gas. The second stream of ammonia enters the ammonia decomposition reactor to exchange heat with the high-temperature flue gas to generate a mixture of hydrogen and nitrogen. This mixture is then fed into a deammoniation tower to remove uncracked ammonia, and then into a hydrogen extraction tower for purification to obtain hydrogen. The hydrogen is mixed with natural gas output from the natural gas supply unit in a natural gas-hydrogen mixer, and then fed into a hydrogen-blended power generation turbine for combustion and power generation. The third stream of ammonia is mixed with natural gas output from the natural gas supply unit in a natural gas-ammonia mixer, and then fed into an ammonia-blended power generation turbine for combustion and power generation.

[0033] The ammonia-hydrogen blending power generation system for gas-fired power plant thermal cycle and tail gas treatment provided in this invention combines the advantages and disadvantages of ammonia and hydrogen as new energy sources. It leverages the ease of storage and transportation of liquid ammonia to supply large-scale hydrogen for on-site hydrogen blending combustion in gas-fired power plants, or directly supplies ammonia for power generation. Simultaneously, this technology utilizes waste heat from the gas turbine for tail gas denitrification, reducing carbon and nitrogen emissions while recovering waste heat, thus improving cycle thermal efficiency and achieving energy conservation and emission reduction. Since hydrogen and ammonia combustion produces no carbon dioxide emissions, gradually increasing the proportion of ammonia and hydrogen blending combustion can reduce the power plant's carbon emissions. Utilizing waste heat from the gas-fired power plant for liquid ammonia vaporization and providing heat energy for ammonia decomposition allows for waste heat recovery while reducing carbon emissions, improving cycle thermal efficiency. Furthermore, using liquid ammonia for tail gas denitrification reduces the concentration of nitrogen oxides in the flue gas, achieving comprehensive utilization of liquid ammonia. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0035] Figure 1 This is a schematic diagram of the structure of the ammonia- and hydrogen-blended power generation system for the thermal cycle and exhaust gas treatment of a gas-fired power plant provided in an embodiment of the present invention.

[0036] Figure label:

[0037] 1. Liquid ammonia storage unit; 2. Eighth regulating valve; 3. Liquid ammonia pump; 4. Vaporizer; 5. Buffer tank; 6. First blower; 7. Air-ammonia mixer; 8. Second blower; 9. Denitrification reactor; 10. Seventh regulating valve; 11. Ammonia decomposition reactor; 12. Cooler; 13. Ammonia removal tower; 14. Hydrogen extraction tower; 15. Hydrogen compressor; 16. Natural gas supply unit; 17. Natural gas-hydrogen mixer; 18. Natural gas-ammonia mixer; 19. Hydrogen-blended power generation turbine; 20. Ammonia-blended power generation turbine; 21. Third regulating valve; 22. First regulating valve; 23. Second regulating valve; 24. Fourth regulating valve; 25. Fifth regulating valve; 26. Sixth regulating valve; 27. Ammonia compressor; 28. Ninth regulating valve; 29. ​​Tenth regulating valve; 30. First pipeline; 31. Second pipeline; 32. Third pipeline; 33. Fourth pipeline; 34. Fifth pipeline. Detailed Implementation

[0038] The 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 should not be construed as limiting the scope of the invention.

[0039] In the description of the embodiments of the present invention, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present invention 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. Therefore, they should not be construed as limitations on the embodiments of the present invention. In addition, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0040] In the description of the embodiments of the present invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" 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. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of the present invention based on the specific circumstances.

[0041] In embodiments of the present invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0042] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0043] The following is combined with Figure 1 This invention describes the specific structure and working principle of an ammonia- and hydrogen-blended power generation system for gas-fired power plant thermal cycle and exhaust gas treatment, according to an embodiment of the present invention.

[0044] Figure 1 A schematic diagram of the structure of the ammonia- and hydrogen-blended power generation system for the thermal cycle and exhaust gas treatment of a gas-fired power plant provided in an embodiment of the present invention is illustrated, as follows: Figure 1 As shown, the ammonia-hydrogen blending power generation system for the thermal cycle and exhaust gas treatment of the gas-fired power plant includes a liquid ammonia storage device 1, a liquid ammonia pump 3, a vaporizer 4, a mixing device, a denitrification reactor 9, an ammonia decomposition reactor 11, a deammoniation tower 13, a hydrogen extraction tower 14, a natural gas supply device 16, a natural gas-hydrogen mixer 17, a natural gas-ammonia mixer 18, a hydrogen blending power generation turbine 19, and an ammonia blending power generation turbine 20.

[0045] The liquid ammonia storage device 1 is used to store liquid ammonia. The liquid ammonia storage device 1 can be a metal pressurized liquid ammonia storage tank or a double-walled concrete tank. Liquid ammonia can be transported to its destination by liquid ammonia tank truck, liquid ammonia type C tank or liquid ammonia tank container and unloaded into the liquid ammonia storage device 1 for storage.

[0046] The outlet of the liquid ammonia storage device 1 is connected to the first end of the first pipeline 30. The liquid ammonia pump 3, vaporizer 4, and mixing device are connected in series on the first pipeline 30. The second end of the first pipeline 30 is connected to the first air inlet of the denitrification reactor 9. The liquid ammonia pump 3 is used to pump the liquid ammonia in the liquid ammonia storage device 1 to the vaporizer 4. The vaporizer 4 is used to vaporize the liquid ammonia to form ammonia gas. The vaporizer 4 can be a water bath type or an electrically heated type vaporizer.

[0047] The first outlet of the ammonia decomposition reactor 11 is connected to the second inlet of the denitrification reactor 9 via a second pipeline 31. Flue gas enters the ammonia decomposition reactor 11 through the flue gas inlet. The temperature at the flue gas inlet of the ammonia decomposition reactor 11 is approximately 600℃, and the temperature at the first outlet of the ammonia decomposition reactor 11 is 300-400℃. An ammonia decomposition catalyst is arranged in the ammonia decomposition reactor 11. The ammonia decomposition catalyst includes nickel-based, iron-based, and ruthenium-based catalysts. The reactor structure and reaction temperature vary depending on the type of catalyst, and are specifically designed according to actual conditions. In this embodiment, a ruthenium-based catalyst is used, and the reaction temperature is 550℃. The ammonia decomposition reactor 11 is equipped with an electric auxiliary heating device, which complements the temperature of the gas after heat exchange. The denitrification reactor 9 is equipped with a denitrification catalyst, and the reaction temperature varies depending on the catalyst, ranging from approximately 200-400℃. The denitrification reactor 9 uses ammonia as a reducing agent, which reacts with nitrogen oxides in the flue gas under the action of the catalyst to generate nitrogen and water, thereby denitrifying the exhaust gas and reducing nitrogen emissions.

[0048] The inlet of the ammonia decomposition reactor 11 is connected to the first pipeline 30 between the vaporizer 4 and the mixing device via the third pipeline 32. The second outlet of the ammonia decomposition reactor 11 is connected to the first end of the fourth pipeline 33. The ammonia removal tower 13, the hydrogen extraction tower 14, and the natural gas-hydrogen mixer 17 are connected in series on the fourth pipeline 33. The inlet of the hydrogen-blended power generation turbine 19 is connected to the second end of the fourth pipeline 33. The inlet of the ammonia-blended power generation turbine 20 is connected to the third pipeline 32 via the fifth pipeline 34. The natural gas-ammonia mixer 18 is connected in series on the fifth pipeline 34. The first outlet of the natural gas supply device 16 is connected to the fourth pipeline 33, and the second outlet of the natural gas supply device 16 is connected to the fifth pipeline 34.

[0049] The ammonia gas input through the third pipeline 32 enters the ammonia decomposition reactor 11 and exchanges heat with the high-temperature flue gas to generate a mixture of hydrogen and nitrogen. The ammonia removal tower 13 is used to remove uncracked ammonia gas from the mixture. The ammonia removal tower 13 adopts molecular sieve desorption technology.

[0050] Hydrogen extraction tower 14 is used to purify hydrogen. Hydrogen extraction tower 14 adopts PSA technology, and the outlet design pressure of hydrogen extraction tower 14 is 1-2 MPa. Natural gas hydrogen mixer 17 has a 2-inlet and 1-outlet structure. Natural gas comes from the plant's natural gas system. After being pressurized, hydrogen and natural gas enter the natural gas hydrogen mixer 17 together.

[0051] The ammonia-hydrogen blending power generation system for gas-fired power plant thermal cycle and tail gas treatment provided in this invention combines the advantages and disadvantages of ammonia and hydrogen as new energy sources. It leverages the ease of storage and transportation of liquid ammonia to supply large-scale hydrogen for on-site hydrogen blending combustion in gas-fired power plants, or directly supplies ammonia for combustion power generation. Simultaneously, this technology utilizes waste heat from the gas turbine for tail gas denitrification treatment, reducing carbon and nitrogen emissions while recovering waste heat, thus improving cycle thermal efficiency and achieving energy conservation and emission reduction. Since hydrogen and ammonia combustion produces no carbon dioxide emissions, gradually increasing the proportion of ammonia and hydrogen blending combustion can reduce the power plant's carbon emissions. Utilizing waste heat from the gas-fired power plant for liquid ammonia vaporization and providing heat energy for ammonia decomposition allows for waste heat recovery while reducing carbon emissions, improving cycle thermal efficiency. Using liquid ammonia for tail gas denitrification treatment reduces the concentration of nitrogen oxides in the flue gas, achieving comprehensive utilization of liquid ammonia.

[0052] It should be noted here that, in this invention, "connected in series" refers to several reactors connected along the flow direction of the medium in the pipeline (i.e., ...). Figure 1 The reactors are arranged sequentially from left to right, with the outlet of the previous reactor connected to the inlet of the next reactor via a pipeline. For example... Figure 1 The liquid ammonia pump 3, vaporizer 4, and mixing device are connected in series on the first pipeline 30 from left to right. Specifically, the inlet of the liquid ammonia pump 3 is connected to the outlet of the liquid ammonia storage device 1 through the first pipeline 30, the inlet of the vaporizer 4 is connected to the outlet of the liquid ammonia pump 3 through the first pipeline 30, the inlet of the mixing device is connected to the outlet of the vaporizer 4 through the first pipeline 30, and the outlet of the mixing device is connected to the first air inlet of the denitrification reactor 9 through the first pipeline 30.

[0053] In one embodiment of the present invention, the mixing device includes an air-ammonia mixer 7 and a first blower 6. The air-ammonia mixer 7 is connected in series to a first pipeline 30 between the vaporizer 4 and the denitrification reactor 9. The outlet of the first blower 6 is connected to the air inlet of the air-ammonia mixer 7. The air-ammonia mixer 7 is used to mix the input ammonia gas with the air delivered by the first blower 6. During operation, the first blower 6 delivers outside air to the air-ammonia mixer 7, which mixes the input ammonia gas with the air delivered by the first blower 6. The air content in the mixed gas can be controlled by controlling the rotational speed of the first blower 6.

[0054] In one embodiment of the present invention, the ammonia-hydrogen blending power generation system for the thermal cycle and exhaust gas treatment of the gas-fired power plant further includes a buffer tank 5, which is connected in series to a first pipeline 30 between the vaporizer 4 and the air-ammonia mixer 7. After the liquid ammonia is vaporized in the vaporizer 4, the ammonia gas is transported to the buffer tank 5, so that the pressure of the ammonia gas provides a stable flow rate of ammonia gas for subsequent applications.

[0055] In one embodiment of the present invention, the ammonia-hydrogen blending power generation system for the thermal cycle and exhaust gas treatment of a gas-fired power plant further includes a second fan 8, which is connected in series to a first pipeline 30 between the air-ammonia mixer 7 and the denitrification reactor 9. Specifically, the inlet of the buffer tank 5 is connected to the outlet of the vaporizer 4 through the first pipeline 30, the outlet of the buffer tank 5 is connected to the inlet of the second fan 8 through the first pipeline 30, and the outlet of the second fan 8 is connected to the first inlet of the denitrification reactor 9 through the first pipeline 30. The mixed gas output from the air-ammonia mixer 7 enters the second fan 8 and is pressurized by the second fan 8, thereby stabilizing the flow rate of the mixed gas entering the denitrification reactor 9. By controlling the second fan 8, the flow rate of the mixed gas entering the denitrification reactor 9 can be controlled.

[0056] In one embodiment of the present invention, the ammonia-hydrogen blending power generation system for the thermal cycle and tail gas treatment of a gas-fired power plant further includes a cooler 12. The cooler 12 is connected in series on a fourth pipeline 33 between the ammonia decomposition reactor 11 and the ammonia removal tower 13. The cooler 12 is used to cool the hydrogen and nitrogen mixture output from the ammonia decomposition reactor 11. Specifically, the inlet of the cooler 12 is connected to the second outlet of the ammonia decomposition reactor 11 through the fourth pipeline 33, the outlet of the cooler 12 is connected to the inlet of the ammonia removal tower 13 through the fourth pipeline 33, and the outlet of the ammonia removal tower 13 is connected to the inlet of the hydrogen extraction tower 14 through the fourth pipeline 33. Because the temperature of the mixed gas output from the ammonia decomposition reactor 11 is relatively high, the mixed gas is first fed into the cooler 12 for cooling before removing uncracked ammonia from the mixed gas. After the temperature of the mixed gas reaches a predetermined temperature, it is then sent to the ammonia removal tower 13.

[0057] In one embodiment of the present invention, the ammonia-hydrogen blending power generation system for the thermal cycle and tail gas treatment of a gas-fired power plant further includes a hydrogen compressor 15, which is connected in series on a fourth pipeline 33 between the hydrogen extraction tower 14 and the natural gas-hydrogen mixer 17. Specifically, the inlet of the hydrogen compressor 15 is connected to the outlet of the hydrogen extraction tower 14 through the fourth pipeline 33, the outlet of the hydrogen compressor 15 is connected to the inlet of the natural gas-hydrogen mixer 17 through the fourth pipeline 33, and the outlet of the natural gas-hydrogen mixer 17 is connected to the inlet of the hydrogen-blended power generation turbine 19 through the fourth pipeline 33. After the mixed gas is purified by the hydrogen extraction tower 14, hydrogen is obtained. Due to the reduction in gas volume, the pressure and flow rate of the hydrogen are both reduced. Therefore, it is necessary to increase the hydrogen pressure output from the hydrogen extraction tower 14 by using the hydrogen compressor 15. The hydrogen is then compressed to the pressure required by the hydrogen-blended power generation turbine 19 by the hydrogen compressor 15 and mixed with natural gas.

[0058] In one embodiment of the present invention, the ammonia-hydrogen blending power generation system for the thermal cycle and exhaust gas treatment of a gas-fired power plant further includes an ammonia compressor 27. The ammonia compressor 27 is connected in series with a fifth pipeline 34 between the third pipeline 32 and the natural gas-ammonia mixer 18. Specifically, the inlet of the ammonia compressor 27 is connected to the third pipeline 32 through the fifth pipeline 34, and the outlet of the ammonia compressor 27 is connected to the inlet of the natural gas-ammonia mixer 18 through the fifth pipeline 34. The outlet of the natural gas-ammonia mixer 18 is connected to the air inlet of the ammonia-blended power generation turbine 20 through the fifth pipeline 34. Since the ammonia pressure input to the third pipeline 32 is low, the ammonia pressure needs to be increased before the ammonia is mixed with the natural gas. Therefore, an ammonia compressor 27 is installed between the third pipeline 32 and the natural gas-ammonia mixer 18 to increase the ammonia pressure input to the third pipeline 32. After the ammonia reaches a predetermined pressure, the ammonia is mixed with the natural gas.

[0059] In one embodiment of the present invention, the ammonia-hydrogen blending power generation system for the thermal cycle and tail gas treatment of the gas-fired power plant further includes a first regulating valve 22, a second regulating valve 23 and a third regulating valve 21. The first regulating valve 22 is disposed in the third pipeline 32, the second regulating valve 23 is disposed in the third pipeline 32 between the first regulating valve 22 and the ammonia decomposition reactor 11, and the third regulating valve 21 is disposed in the fifth pipeline 34 between the ammonia compressor 27 and the third pipeline 32. The third regulating valve 21 is used to regulate the opening and closing of the third pipeline 32.

[0060] Specifically, the first port of the first regulating valve 22 is connected to the first pipeline 30 between the buffer tank 5 and the air-ammonia mixer 7; the first port of the second regulating valve 23 is connected to the second port of the first regulating valve 22 via the third pipeline 32; and the second port of the second regulating valve 23 is connected to the air inlet of the ammonia decomposition reactor 11 via the third pipeline 32. Preferably, the fifth pipeline 34 is connected to the third pipeline 32 between the first regulating valve 22 and the second regulating valve 23.

[0061] In one embodiment of the present invention, the ammonia-hydrogen blending power generation system for the thermal cycle and tail gas treatment of a gas-fired power plant further includes a fourth regulating valve 24, a fifth regulating valve 25, and a sixth regulating valve 26. The fourth regulating valve 24 is disposed in a fourth pipeline 33 between the hydrogen compressor 15 and the natural gas-hydrogen mixer 17. The fifth regulating valve 25 is disposed in the first outlet of the natural gas supply device 16, and the sixth regulating valve 26 is disposed in the second outlet of the natural gas supply device 16. Specifically, the first interface of the fourth regulating valve 24 is connected to the outlet of the hydrogen compressor 15 through the fourth pipeline 33, and the second interface of the fourth regulating valve 24 is connected to the inlet of the natural gas-hydrogen mixer 17 through the fourth pipeline 33. The first interface of the fifth regulating valve 25 is connected to the fourth pipeline 33 between the fourth regulating valve 24 and the natural gas-hydrogen mixer 17, and the second interface of the fifth regulating valve 25 is connected to the first outlet of the natural gas supply device 16. The first port of the sixth regulating valve 26 is connected to the fifth pipeline 34 between the ammonia compressor 27 and the natural gas ammonia mixer 18, and the second port of the sixth regulating valve 26 is connected to the second outlet of the natural gas supply device 16.

[0062] The ammonia- and hydrogen-blended power generation system for the thermal cycle and exhaust gas treatment of a gas-fired power plant has two power generation modes: hydrogen blending and ammonia blending. Switching between these two modes can be achieved by adjusting valves. When using hydrogen blending, the third regulating valve 21 and the sixth regulating valve 26 are closed, and the second regulating valve 23 and the fifth regulating valve 25 are opened. When using ammonia blending, the second regulating valve 23 and the fifth regulating valve 25 are closed, and the third regulating valve 21 and the sixth regulating valve 26 are opened.

[0063] In one embodiment of the present invention, the ammonia- and hydrogen-blended power generation system for the thermal cycle and exhaust gas treatment of the gas-fired power plant further includes a seventh regulating valve 10, which is disposed on the second pipeline 31. The seventh regulating valve 10 is used to control the opening and closing of the second pipeline 31, and can also control the flow rate of flue gas entering the denitrification reactor 9.

[0064] In one embodiment of the present invention, the ammonia-hydrogen blending power generation system for gas-fired power plant thermal cycle and exhaust gas treatment further includes an eighth regulating valve 2, which is disposed on the first pipeline 30 between the liquid ammonia storage device 1 and the liquid ammonia pump 3.

[0065] In one embodiment of the present invention, the ammonia-hydrogen blending power generation system for the thermal cycle and exhaust gas treatment of the gas-fired power plant further includes a ninth regulating valve 28, which is disposed on the first pipeline 30 between the liquid ammonia pump 3 and the vaporizer 4.

[0066] In one embodiment of the present invention, the ammonia- and hydrogen-blended power generation system for the thermal cycle and exhaust gas treatment of the gas-fired power plant further includes a tenth regulating valve 29, which is disposed on the first pipeline 30 between the vaporizer 4 and the buffer tank 5.

[0067] It should be noted that the regulating valves of this invention are all made of 316 stainless steel, which can resist hydrogen embrittlement for a long time in pure hydrogen medium, and the accuracy is controlled within 1%.

[0068] To precisely control the flow rates of natural gas and hydrogen, in a preferred embodiment of the present invention, a natural gas flow meter (not shown) is installed on the pipeline between the natural gas supply device 16 and the natural gas-hydrogen mixer 17; a hydrogen flow meter (not shown) is installed on the fourth pipeline 33 between the hydrogen extraction tower 14 and the natural gas-hydrogen mixer 17; and a hydrogen analyzer (not shown) is installed on the fourth pipeline 33 between the natural gas-hydrogen mixer 17 and the hydrogen-blended generator turbine 19. The natural gas flow meter, hydrogen flow meter, and hydrogen analyzer are all electrically connected to a control device, which is electrically connected to each of the aforementioned regulating valves. The control device acquires and calculates the flow rates of natural gas, hydrogen, and the natural gas-hydrogen mixture, and controls the opening degree of the fourth regulating valve 24 or the fifth regulating valve 25 based on the calculation results to control the proportion of hydrogen in the mixture.

[0069] Natural gas and hydrogen are mixed in a static mixer, and a hydrogen analyzer monitors the hydrogen content in the resulting mixture. Furthermore, the control unit is equipped with an alarm that sounds when the hydrogen content exceeds a predetermined range, providing interlocking protection against excessive hydrogen levels.

[0070] The present invention also provides a method for ammonia- and hydrogen-blended power generation involving the thermal cycle and exhaust gas treatment of a gas-fired power plant. The method is based on the ammonia- and hydrogen-blended power generation system for the thermal cycle and exhaust gas treatment of a gas-fired power plant described in any of the above embodiments, and includes:

[0071] In step S100, the liquid ammonia pump 3 sends the liquid ammonia in the liquid ammonia storage device 1 to the vaporizer for vaporization;

[0072] In step S200, the gasified ammonia gas can be divided into three streams. The first stream of ammonia gas enters a mixing device and mixes with air. The mixed gas then enters the denitrification reactor 9 and reacts with the flue gas input from the ammonia decomposition reactor 11 to remove nitrogen oxides from the flue gas. The second stream of ammonia gas enters the ammonia decomposition reactor 11 and exchanges heat with the high-temperature flue gas to generate a mixture of hydrogen and nitrogen. The mixture of hydrogen and nitrogen gas is input into the deammoniation tower 13 to remove uncracked ammonia gas, and then input into the hydrogen extraction tower 14 for purification to obtain hydrogen gas. The hydrogen gas is mixed with the natural gas output from the natural gas supply device 16 in the natural gas-hydrogen mixer 17, and then input into the hydrogen-blended power generation turbine 19 for combustion and power generation. The third stream of ammonia gas is mixed with the natural gas output from the natural gas supply device 16 in the natural gas-ammonia mixer 18, and then input into the ammonia-blended power generation turbine 20 for combustion and power generation.

[0073] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An ammonia-doped hydrogen-doped power generation system for thermal cycle and exhaust gas treatment of a gas power plant, characterized by, The application relates to a hydrogen-ammonia mixed power generation system, which comprises a liquid ammonia storage device (1), a liquid ammonia pump (3), a vaporizer (4), a mixing device, a denitration reactor (9), an ammonia decomposition reactor (11), a deamination tower (13), a hydrogen extraction tower (14), a natural gas supply device (16), a natural gas-hydrogen mixer (17), a natural gas-ammonia mixer (18), a hydrogen-ammonia mixed power generation turbine (19) and a hydrogen-ammonia mixed power generation turbine (20), the liquid outlet of the liquid ammonia storage device (1) is communicated with the first end of a first pipeline (30), the liquid ammonia pump (3), the vaporizer (4) and the mixing device are sequentially connected on the first pipeline (30), the second end of the first pipeline (30) is communicated with the first gas inlet of the denitration reactor (9); the first gas outlet of the ammonia decomposition reactor (11) is communicated with the second gas inlet of the denitration reactor (9) through a second pipeline (31), flue gas enters the ammonia decomposition reactor (11) through a flue gas inlet; the gas inlet of the ammonia decomposition reactor (11) is communicated with the first pipeline (30) between the vaporizer (4) and the mixing device through a third pipeline (32), the second gas outlet of the ammonia decomposition reactor (11) is communicated with the first end of a fourth pipeline (33), the deamination tower (13), the hydrogen extraction tower (14) and the natural gas-hydrogen mixer (17) are sequentially connected on the fourth pipeline (33), the gas inlet of the hydrogen-ammonia mixed power generation turbine (19) is communicated with the second end of the fourth pipeline (33); the gas inlet of the hydrogen-ammonia mixed power generation turbine (20) is communicated with the third pipeline (32) through a fifth pipeline (34), the natural gas-ammonia mixer (18) is connected on the fifth pipeline (34), the first gas outlet of the natural gas supply device (16) is communicated with the fourth pipeline (33), the second gas outlet of the natural gas supply device (16) is communicated with the fifth pipeline (34), the ammonia gas input into the ammonia decomposition reactor (11) through the third pipeline (32) exchanges heat with high-temperature flue gas to generate hydrogen and nitrogen mixed gas.

2. The ammonia and hydrogen doped power generation system for thermal cycle and exhaust treatment of a gas power plant according to claim 1, characterized by, The mixing device comprises: an air-ammonia mixer (7) connected on the first pipeline (30) between the vaporizer (4) and the denitration reactor (9); a first fan (6), the gas outlet of the first fan (6) is communicated with the air inlet of the air-ammonia mixer (7), and the air-ammonia mixer (7) is used for mixing the input ammonia gas with the air delivered by the first fan (6).

3. The ammonia and hydrogen doped power generation system for thermal cycle and exhaust treatment of a gas power plant according to claim 2, characterized by, Further comprising: a buffer tank (5) connected on the first pipeline (30) between the vaporizer (4) and the air-ammonia mixer (7).

4. The ammonia and hydrogen doped power generation system for thermal cycle and exhaust treatment of a gas power plant according to claim 2, characterized by, Further comprising: a second fan (8) connected on the first pipeline (30) between the air-ammonia mixer (7) and the denitration reactor (9).

5. Ammonia and hydrogen doped power generation system for thermal cycle and exhaust treatment of a gas power plant according to any one of claims 1 to 4, characterized by the fact that, Further comprising: a cooler (12) connected on the fourth pipeline (33) between the ammonia decomposition reactor (11) and the deamination tower (13), and the cooler (12) is used for cooling the hydrogen and nitrogen mixed gas output by the ammonia decomposition reactor (11).

6. Ammonia and hydrogen doped power generation system for thermal cycle and exhaust treatment of a gas power plant according to any one of claims 1 to 4, characterized by the fact that, Further comprising: A hydrogen compressor (15) is connected in series to the fourth pipeline (33) between the hydrogen extraction tower (14) and the natural gas hydrogen mixer (17), and is used to increase the pressure of hydrogen output by the hydrogen extraction tower (14).

7. Ammonia and hydrogen doped power generation system for thermal cycle and exhaust treatment of a gas power plant according to any of claims 1 to 4, characterized by the fact that, Further comprising: An ammonia compressor (27) is connected in series to the fifth pipeline (34) between the third pipeline (32) and the natural gas ammonia mixer (18), and is used to increase the pressure of ammonia input by the third pipeline (32).

8. The ammonia and hydrogen doped power generation system for thermal cycle and exhaust treatment of a gas power plant according to claim 7, characterized by, Further comprising: A first regulating valve (22) is arranged in the third pipeline (32); A second regulating valve (23) is arranged in the third pipeline (32) between the first regulating valve (22) and the ammonia decomposition reactor (11); A third regulating valve (21) is arranged in the fifth pipeline (34) between the ammonia compressor (27) and the third pipeline (32).

9. The ammonia and hydrogen doped power generation system for thermal cycle and exhaust treatment of a gas power plant according to claim 6, characterized by, Further comprising: A fourth regulating valve (24) is arranged in the fourth pipeline (33) between the hydrogen compressor (15) and the natural gas hydrogen mixer (17); A fifth regulating valve (25) is arranged at the first gas outlet of the natural gas supply device (16); A sixth regulating valve (26) is arranged at the second gas outlet of the natural gas supply device (16).

10. An ammonia-hydrogen-doping power generation method that intervenes in the thermal cycle and exhaust gas treatment of a gas power plant, said method being based on the ammonia-hydrogen-doping power generation system of the thermal cycle and exhaust gas treatment of a gas power plant according to any one of claims 1 to 9, characterized in that, Comprising: The liquid ammonia pump (3) sends the liquid ammonia in the liquid ammonia storage device (1) to the vaporizer for gasification; The gasified ammonia gas is divided into three paths, the first path of ammonia gas enters the mixing device and mixes with air, and the mixed gas enters the denitration reactor (9) and reacts with the flue gas input by the ammonia decomposition reactor (11) to remove nitrogen oxides in the flue gas; the second path of ammonia gas enters the ammonia decomposition reactor (11) and exchanges heat with high-temperature flue gas to generate mixed gas of hydrogen and nitrogen, the mixed gas of hydrogen and nitrogen is input into the deamination tower (13) to remove uncracked ammonia gas, and then input into the hydrogen extraction tower (14) to obtain hydrogen, the hydrogen and natural gas output by the natural gas supply device (16) are mixed in the natural gas hydrogen mixer (17), and then input into the hydrogen-doped power generation turbine (19) for combustion power generation; the third path of ammonia gas and the natural gas output by the natural gas supply device (16) are mixed in the natural gas ammonia mixer (18), and then input into the ammonia-doped power generation turbine (20) for combustion power generation.

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