Gas turbine plant

Abstract

To yield an amount of gas ammonia generation required by a gas turbine.SOLUTION: A gas turbine plant comprises a gas turbine and a fuel supply facility. The fuel supply facility includes: a liquid ammonia line; a hot water line in which hot water can flow; an evaporator which can heat and evaporate the liquid ammonia by causing heat exchange between the hot water from the hot water line and the liquid ammonia from the liquid ammonia line; a heat exchanger which can cause heat exchange between the hot water in the hot water line and a medium; a heat exchange amount adjuster which can adjust the temperature of the hot water flowing into the evaporator by adjusting an amount of heat exchange between the hot water and the medium; and a gas ammonia line which can direct the gas ammonia representing ammonia that has been evaporated by the evaporator into the gas turbine.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a gas turbine plant.

Background Art

[0002] A gas turbine plant has a gas turbine and a fuel supply facility that supplies fuel to the gas turbine.

[0003] In the gas turbine plant described in Patent Document 1 below, ammonia is used as fuel and supplied to the gas turbine. This gas turbine plant includes, in addition to a fuel supply facility that supplies ammonia as fuel to the gas turbine, an exhaust heat recovery boiler that generates steam using the heat of the exhaust gas from the gas turbine.

[0004] The fuel supply facility includes an ammonia tank that stores liquid ammonia, a liquid ammonia line connected to the ammonia tank, a hot water line through which hot water can flow, a vaporizer, a flow control valve that adjusts the flow rate of the hot water flowing into the vaporizer, and a gaseous ammonia line that guides gaseous ammonia to the gas turbine. The vaporizer is connected to the end of the liquid ammonia line. The vaporizer heats and vaporizes the liquid ammonia by heat-exchanging the hot water from the hot water line and the liquid ammonia from the liquid ammonia line.

[0005] The vaporizer has a heat transfer tube through which ammonia flows and a vaporizer casing that covers the heat transfer tube and temporarily stores hot water. The hot water line is disposed in the exhaust heat recovery boiler and has a hot water heater that heat-exchanges the hot water and the exhaust gas to heat the hot water, a high-temperature water line that guides the high-temperature water heated by the hot water heater into the vaporizer casing, and a low-temperature water line that connects the vaporizer casing and the hot water heater. The flow control valve is provided in the high-temperature water line.

[0006] In this fuel supply system, the flow rate of hot water entering the vaporizer casing is regulated by a flow control valve to maintain the temperature of the hot water within the vaporizer casing within a target temperature range. Then, heat exchange occurs between the hot water in the vaporizer casing and the liquid ammonia flowing through the heat transfer tubes. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Patent No. 6245404 [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] The temperature of the exhaust gas flowing through the waste heat recovery boiler changes with changes in the operating conditions of the gas turbine. Therefore, in the technology described in Patent Document 1, even if the flow rate of hot water flowing into the vaporizer casing is changed in an environment where the exhaust gas temperature changes, the amount of heat exchange between liquid ammonia and hot water is not proportional to the flow rate of hot water, making it difficult to control this amount of heat exchange. Thus, it is thought that the technology described in Patent Document 1 may not be able to secure the required amount of gaseous ammonia to be produced.

[0009] Therefore, the purpose of this disclosure is to provide a technology that can easily obtain the amount of gaseous ammonia required by a gas turbine. [Means for solving the problem]

[0010] A gas turbine plant as one embodiment for achieving the aforementioned objective is: The system comprises a gas turbine that burns fuel and is driven by combustion gas produced by the combustion of the fuel, a waste heat recovery boiler that generates steam using the heat of exhaust gas from the gas turbine, and a fuel supply system that can supply ammonia as fuel to the gas turbine. The fuel supply system includes a liquid ammonia line connected to an ammonia tank capable of storing liquid ammonia, a high-temperature water line through which hot water heated by heat exchange with the exhaust gas in the waste heat recovery boiler can flow, a vaporizer connected to the liquid ammonia line that can heat and vaporize the liquid ammonia by heat exchange between the hot water from the high-temperature water line and the liquid ammonia, a heat exchanger provided in the high-temperature water line that can heat exchange between the hot water and a medium, a heat exchange rate regulator that can adjust the amount of heat exchange between the hot water and the medium to adjust the temperature of the hot water flowing into the vaporizer, and a gaseous ammonia line that can guide gaseous ammonia, which is the ammonia vaporized in the vaporizer, to the gas turbine.

[0011] In this embodiment, hot water heated by heat exchange between hot water and exhaust gas in a hot water heater flows into a vaporizer after its temperature is regulated. In this vaporizer, the temperature-regulated hot water and liquid ammonia exchange heat, causing the ammonia to vaporize. However, since the exhaust gas temperature at the gas turbine outlet changes due to changes in the gas turbine's operating conditions, the temperature at the inlet of the hot water heater in the heat recovery boiler changes depending on the gas turbine's operating conditions. Therefore, when the exhaust gas temperature changes, the temperature of the hot water heated in the hot water heater also changes. However, in this embodiment, as mentioned above, the hot water heated in the hot water heater flows into the vaporizer after its temperature is regulated. Therefore, in this embodiment, even if the exhaust gas temperature changes, all of the liquid ammonia flowing into the vaporizer can be easily converted into gaseous ammonia.

[0012] Furthermore, the amount of gaseous ammonia required by the gas turbine also changes depending on the operating conditions of the gas turbine. In this embodiment, even if the amount of gaseous ammonia required by the gas turbine changes, all of the liquid ammonia flowing into the vaporizer can be easily converted into gaseous ammonia by changing the temperature of the hot water flowing into the vaporizer.

[0013] Therefore, in this embodiment, even if the operating conditions of the gas turbine change, the amount of gaseous ammonia required by the gas turbine can be easily obtained. Furthermore, in this embodiment, the responsiveness of the amount of gaseous ammonia produced to changes in the operating conditions of the gas turbine can be improved.

[0014] A fuel supply method for a gas turbine plant, as one embodiment for achieving the aforementioned objective, is: A fuel supply method for a gas turbine plant comprising a gas turbine that burns fuel and is driven by combustion gas produced by the combustion of the fuel, and a heat recovery boiler that generates steam using the heat of exhaust gas from the gas turbine, comprising: a hot water heating step of heating the hot water by exchanging heat between the hot water in a hot water heater located in the heat recovery boiler and the exhaust gas located in the heat recovery boiler but outside the hot water heater; a heat exchange step of exchanging heat between the hot water heated in the hot water heating step and a medium; a heat exchange amount adjustment step of adjusting the amount of heat exchanged between the hot water heated in the hot water heating step and the medium; a vaporization step of exchanging heat between the hot water, after the amount of heat exchange with the medium has been adjusted by the heat exchange amount adjustment step, and liquid ammonia from an ammonia tank storing liquid ammonia in a vaporizer to vaporize the liquid ammonia; and a fuel supply step of supplying the gaseous ammonia, which is the ammonia vaporized in the vaporization step, as fuel to the gas turbine. In the heat exchange amount adjustment step, the temperature of the hot water flowing into the vaporizer is adjusted by adjusting the amount of heat exchange between the hot water and the medium in the heat exchange step.

[0015] Also in this aspect, similar to one aspect of the gas turbine plant, even when the operating conditions of the gas turbine change, it is possible to easily obtain the amount of gaseous ammonia required by the gas turbine. Further, in this aspect as well, it is possible to enhance the responsiveness of the amount of gaseous ammonia production with respect to changes in the operating conditions of the gas turbine.

Advantages of the Invention

[0016] In one aspect of the present disclosure, it is possible to obtain the amount of gaseous ammonia required by the gas turbine.

Brief Description of the Drawings

[0017] [Figure 1] It is a system diagram of a gas turbine plant in a first embodiment according to the present disclosure. [Figure 2] It is a functional block diagram of a control device in a first embodiment according to the present disclosure. [Figure 3] It is a graph showing the relationship between the fuel flow rate and the target temperature in a first embodiment according to the present disclosure. [Figure 4] It is a flowchart showing the procedure of a fuel supply method in a first embodiment according to the present disclosure. [Figure 5] It is a system diagram of a gas turbine plant in a second embodiment according to the present disclosure. [Figure 6] It is a flowchart showing the procedure of a fuel supply method in a second embodiment according to the present disclosure. [Figure 7] It is a functional block diagram of a control device in a modification example according to the present disclosure.

Modes for Carrying Out the Invention

[0018] Hereinafter, various embodiments and various modification examples according to the present disclosure will be described with reference to the drawings.

[0019] 「First Embodiment」 Hereinafter, a first embodiment of a gas turbine plant according to the present disclosure will be described with reference to FIGS. 1 to 4.

[0020] As shown in FIG. 1, the gas turbine plant of this embodiment includes a gas turbine 10, a denitration device 20 that decomposes NOx contained in the exhaust gas from the gas turbine 10, an exhaust heat recovery boiler 21 that generates steam by using the heat of the exhaust gas flowing out from the denitration device 20, a chimney 22 that exhausts the exhaust gas from the exhaust heat recovery boiler 21 to the outside, a steam turbine 23 driven by the steam from the exhaust heat recovery boiler 21, a condenser 24 that returns the steam from the steam turbine 23 to water, a pump 25 that sends the water in the condenser 24 to the exhaust heat recovery boiler 21, a fuel supply facility 40 that supplies fuel to the gas turbine 10, and a control device 60. Therefore, the gas turbine plant of this embodiment is a combined cycle plant.

[0021] The gas turbine 10 includes a compressor 14 that compresses air A, a combustor 15 that burns fuel in the air compressed by the compressor 14 to generate combustion gas, and a turbine 16 driven by the high-temperature and high-pressure combustion gas.

[0022] The compressor 14 has a compressor rotor 14r that rotates about a rotor axis Ar, a compressor casing 14c that covers the compressor rotor 14r, and an intake air amount regulator (hereinafter referred to as IGV (inlet guide vane)) 14i provided at the intake port of the compressor casing 14c. The IGV 14i adjusts the flow rate of the air sucked into the compressor casing 14c according to an instruction from the control device 60. The turbine 16 has a turbine rotor 16r that rotates about the rotor axis Ar by the combustion gas from the combustor 15, and a turbine casing 16c that covers the turbine rotor 16r. The turbine rotor 16r and the compressor rotor 14r are interconnected so as to be rotatable about the same rotor axis Ar, forming a gas turbine rotor 11. For example, a rotor of a generator is connected to the gas turbine rotor 11.

[0023] The gas turbine 10 further includes an intermediate casing 12. The intermediate casing 12 is positioned between the compressor casing 14c and the turbine casing 16c in the direction in which the rotor axis Ar extends, and connects the compressor casing 14c and the turbine casing 16c. Compressed air discharged from the compressor 14 flows into this intermediate casing 12. A combustor 15 is also fixed to this intermediate casing 12.

[0024] Ammonia is supplied to the denitrification unit 20. This denitrification unit 20 uses this ammonia to decompose NOx contained in the exhaust gas from the gas turbine 10 into nitrogen and water vapor.

[0025] The waste heat recovery boiler 21 includes a boiler casing 21c through which exhaust gas from the denitrification unit 20 flows, an economizer 21eco, an evaporator 21eva, and a superheater 21s. The economizer 21eco, evaporator 21eva, and superheater 21s are arranged in the order of economizer 21eco, evaporator 21eva, and superheater 21s from downstream to upstream in the flow of exhaust gas within the boiler casing 21c. The economizer 21eco, evaporator 21eva, and superheater 21s have heat transfer tubes that exchange heat between the exhaust gas flowing within the boiler casing 21c and water or steam. The economizer 21eco exchanges heat between the exhaust gas flowing within the boiler casing 21c and water to heat the water and produce hot water. The evaporator 21eva exchanges heat between the exhaust gas flowing through the boiler casing 21c and the hot water from the economizer 21eco to heat the hot water and generate steam. The superheater 21s exchanges heat between the exhaust gas flowing through the boiler casing 21c and the steam from the evaporator 21eva to heat the steam and generate superheated steam.

[0026] The economizer 21eco and condenser 24 of the heat recovery boiler 21 are connected by a feedwater line 26. A pump 25 is provided in this feedwater line 26 to send water from the condenser 24 to the heat recovery boiler 21. The superheater 21s and steam turbine 23 of the heat recovery boiler 21 are connected by a main steam line 27. Superheated steam from the heat recovery boiler 21 is sent to the steam turbine 23 via the main steam line 27. For example, the rotor of a generator is connected to the rotor of the steam turbine 23. The steam exhausted from the steam turbine 23 is returned to water in the condenser 24.

[0027] The denitrification unit 20 is located, for example, within the boiler casing 21c, near the evaporator 21eva. Ammonia is supplied to this denitrification unit 20. Using this ammonia, the denitrification unit 20 decomposes NOx contained in the exhaust gas from the gas turbine 10 into nitrogen and water vapor.

[0028] The fuel supply equipment 40 includes an ammonia tank 41, a liquid ammonia line 42, a liquid ammonia control valve 43a, a fuel control valve 43b, an ammonia pump 44, a vaporizer 45, a gaseous ammonia line 46, a hot water line 50, a hot water pump 54, a heat exchanger 55, a heat exchange rate regulator 56, a media line 58i, a media recovery line 58o, and a media flow rate regulator 59.

[0029] Liquid ammonia is stored in the ammonia tank 41. One end of the liquid ammonia line 42 is connected to this ammonia tank 41. The liquid ammonia line 42 is equipped with an ammonia pump 44 for pressurizing the liquid ammonia from the ammonia tank 41, and a liquid ammonia control valve 43a for regulating the flow rate of liquid ammonia through the liquid ammonia line 42.

[0030] The vaporizer 45 is a heat exchanger that heats and vaporizes liquid ammonia by exchanging heat between hot water and liquid ammonia. The vaporizer 45 has a heat transfer tube 45p through which hot water flows, and a vaporizer casing 45c that covers the heat transfer tube 45p and temporarily stores liquid ammonia. One end of the heat transfer tube 45p forms a hot water inlet 45pi, and the other end of the heat transfer tube 45p forms a hot water outlet 45po. The vaporizer casing 45c has an ammonia inlet 45ci and an ammonia outlet 45co. The other end of the aforementioned liquid ammonia line 42 is connected to the ammonia inlet 45ci of the vaporizer 45. One end of the gaseous ammonia line 46 is connected to the ammonia outlet 45co of the vaporizer 45. The other end of this gaseous ammonia line 46 is connected to the combustor 15. This gaseous ammonia line 46 is equipped with a fuel control valve 43b that adjusts the flow rate of gaseous ammonia as fuel flowing into the combustor 15.

[0031] The hot water line 50 includes a low-temperature water line 51, a hot water heater 52, and a high-temperature water line 53. The hot water heater 52 is located within the boiler casing 21c, downstream of the economizer 21eco in the exhaust gas flow. The low-temperature water line 51 connects the hot water outlet 45po of the vaporizer 45 to the hot water heater 52. A hot water pump 54 is provided in this low-temperature water line 51. The high-temperature water line 53 includes a main high-temperature water line 53x that connects the hot water heater 52 to the hot water inlet 45pi of the vaporizer 45, and a branch high-temperature water line 53y that branches off from the main high-temperature water line 53x and is connected to the main high-temperature water line 53x.

[0032] The hot water line 50 and the heat transfer tubes 45p of the vaporizer 45 form a hot water circulation line through which hot water circulates. The flow rate of hot water circulating in this hot water circulation line is controlled by the hot water pump 54 and is kept approximately constant.

[0033] The heat exchanger 55 exchanges heat between a medium such as cooling water and hot water. The heat exchanger 55 has heat transfer tubes 55p through which the medium flows, and a heat exchanger casing 55c that covers the heat transfer tubes 55p and temporarily stores the hot water. One end of the heat transfer tubes 55p forms a medium inlet 55pi, and the other end of the heat transfer tubes 55p forms a medium outlet 55po. A medium line 58i is connected to the medium inlet 55pi. A medium flow regulator 59 is provided in this medium line 58i to adjust the flow rate of the medium flowing through it. A medium recovery line 58o is connected to the medium outlet 55po. The heat exchanger casing 55c is provided in the branched high-temperature water line 53y. Therefore, high-temperature water from the branched high-temperature water line 53y flows into the heat exchanger casing 55c. The medium flowing into the heat exchanger 55 may be a liquid such as river water, seawater, or industrial water, or a gas such as air.

[0034] The heat exchange rate regulator 56 has a three-way valve 57 as a flow ratio regulator that adjusts the ratio between the flow rate of hot water flowing between the branching point of the branched hot water line 53y and the connection point of the branched hot water line 53y in the main hot water line 53x, and the flow rate of hot water flowing in the branched hot water line 53y. This three-way valve 57 is installed at the connection point between the main hot water line 53x and the branched hot water line 53y. Alternatively, the flow ratio regulator may be configured not with a three-way valve 57, but with a main hot water control valve installed in the main hot water line 53x between the branching point of the branched hot water line 53y and the connection point of the branched hot water line 53y, and a branched hot water control valve installed in the branched hot water line 53y.

[0035] In the main high-temperature water line 53x, a thermometer 48 is provided between the three-way valve 57 and the vaporizer 45 to detect the temperature of the high-temperature water flowing between them. In the gaseous ammonia line 46, a pressure gauge 49 is provided to detect the pressure of the gaseous ammonia flowing through the line.

[0036] As shown in Figure 2, the control device 60 includes a fuel flow rate calculation unit 61, a fuel valve control unit 62, an IGV control unit 63, a temperature control system 65, and a pressure control system 70.

[0037] The fuel flow rate calculation unit 61 receives a request output PWr from an external source to the gas turbine 10. The fuel flow rate calculation unit 61 determines the fuel flow rate corresponding to this request output PWr and outputs a fuel flow rate command FrO indicating this fuel flow rate. The fuel flow rate determined by this fuel flow rate calculation unit 61 has a positive correlation with the request output PWr. That is, as the request output PWr increases, the fuel flow rate determined by this fuel flow rate calculation unit 61 also increases.

[0038] The fuel valve control unit 62 controls the opening degree of the fuel control valve 43b according to the fuel flow rate command FrO. The IGV control unit 63 controls the opening degree of the IGV 14i according to the fuel flow rate command FrO. Specifically, the IGV control unit 63 controls the IGV opening degree so that it has a positive correlation with the fuel flow rate indicated by the fuel flow rate command FrO. The liquid ammonia control valve 43a changes its valve opening degree according to the amount of liquid ammonia in the vaporizer casing 45c. Specifically, when the amount of liquid ammonia in the vaporizer casing 45c decreases, the liquid ammonia control valve 43a opens to replenish the liquid ammonia.

[0039] The temperature control system 65 includes a target temperature calculator 66, a temperature deviation calculator 67, and a PI controller 68.

[0040] As shown in Figure 3, the target temperature calculator 66 has a function F1 that shows the relationship between the fuel flow rate indicated by the fuel flow rate command FrO and the target temperature of the hot water. This function F1 shows that as the fuel flow rate increases, the target temperature increases. The target temperature calculator 66 uses this function F1 to determine the target temperature of the hot water for the fuel flow rate indicated by the fuel flow rate command FrO.

[0041] The temperature deviation calculator 67 calculates the deviation ΔT between the target temperature and the temperature detected by the thermometer 48. Specifically, the temperature deviation calculator 67 subtracts the temperature detected by the thermometer 48 from the target temperature and outputs this value as the temperature deviation ΔT. The PI controller 68 calculates the opening correction amount for proportional and integral operation according to the temperature deviation ΔT and outputs a valve command to the three-way valve 57 according to this opening correction amount.

[0042] The pressure control system 70 includes a pressure correction mode button 71, a lower limit memory 72a, an upper limit memory 72b, a lower limit deviation calculator 73a, an upper limit deviation calculator 73b, a lower limit deviation judge 74a, an upper limit deviation judge 74b, a lower limit correction indicator 75a, an upper limit correction indicator 75b, a lower limit correction value calculator 77a, an upper limit correction value calculator 77b, a first switch 78a, a second switch 78b, a first adder 79a, a second adder 79b, and a PI controller 68. The pressure control system 70 and the temperature control system 65 share this PI controller 68. The functions of each of the above elements of the pressure control system 70 will be explained in the process of explaining the operation of this pressure control system 70.

[0043] The control device 60 described above is a computer. Hardware-wise, the control device 60 includes a CPU (Central Processing Unit) that performs various calculations, a main memory such as memory that serves as the CPU's work area, an auxiliary storage device such as a hard disk drive, an input device such as a keyboard or mouse, and a display device. Each functional unit in the control device 60, such as the fuel flow rate calculation unit 61, the fuel valve control unit 62, the IGV control unit 63, the temperature control system 65, and the pressure control system 70, functions, for example, when the CPU executes a control program stored in the auxiliary storage device.

[0044] Next, following the flowchart shown in Figure 4, we will explain the fuel supply method for the gas turbine plant described above.

[0045] In this fuel supply method, a hot water heating step S1, a heat exchange amount adjustment step S2, a heat exchange step S3, a temperature control step S4, a vaporization step S6, a low-temperature water recovery step S7, and a fuel supply step S8 are performed. In addition, in this fuel supply method, a pressure control step S5 is also performed upon request from the operator.

[0046] In the hot water heating process S1, the hot water in the hot water heater 52 located inside the boiler casing 21c is heated by exchanging heat between the hot water and the exhaust gas inside the boiler casing 21c but outside the hot water heater 52. In this hot water heating process S1, for example, hot water at approximately 60°C (low-temperature water) is heated to approximately 90°C (high-temperature water). This high-temperature water flows from the hot water heater 52 into the main high-temperature water line 53x.

[0047] In the heat exchange rate adjustment process S2, the amount of heat exchange between the high-temperature water from the hot water heater 52 and the medium flowing into the heat exchanger 55 is adjusted to control the temperature of the high-temperature water flowing into the vaporizer 45. This heat exchange rate adjustment process S2 includes a flow splitting process S2a and a flow rate ratio adjustment process S2b. In the flow splitting process S2a of the heat exchange rate adjustment process S2, a portion of the high-temperature water flowing through the main high-temperature water line 53x is diverted to the branch high-temperature water line 53y, while the remaining high-temperature water is diverted in the main high-temperature water line 53x to the downstream side of the branching point with the branch high-temperature water line 53y. In other words, in this flow splitting process S2a, the high-temperature water flowing through the main high-temperature water line 53x is split into branch high-temperature water flowing through the branch high-temperature water line 53y and main high-temperature water flowing through the main high-temperature water line 53x. The flow rate ratio adjustment process S2b of the heat exchange rate adjustment process S2 will be described later.

[0048] In the heat exchange process S3, a heat exchanger 55 located in the branched high-temperature water line 53y exchanges heat between the branched high-temperature water and the medium flowing into the heat exchanger 55. Here, if the medium flowing into the heat exchanger 55 is cooling water, as described above, the temperature of the branched high-temperature water decreases.

[0049] In the temperature control process S4, the requested output PWr of the gas turbine 10 is received, and the amount of heat exchanged in the heat exchange amount adjustment process S2 is controlled according to the requested output PWr. The temperature control system 65 of the control device 60 executes this temperature control process S4.

[0050] Now, the operation of the control device 60 will be explained with reference to Figure 2.

[0051] As described above, the fuel flow rate calculation unit 61 of the control device 60 receives a request output PWr from an external source to the gas turbine 10. The fuel flow rate calculation unit 61 determines the fuel flow rate corresponding to this request output PWr and outputs a fuel flow rate command FrO indicating this fuel flow rate. Note that the flow rate here is the mass flow rate.

[0052] The fuel valve control unit 62 controls the opening of the fuel control valve 43b so that the mass flow rate of fuel passing through the fuel control valve 43b becomes the fuel flow rate indicated by the fuel flow rate command FrO. As a result, the mass flow rate of ammonia as fuel flowing from the gaseous ammonia line 46 into the combustor 15 becomes the fuel flow rate indicated by the fuel flow rate command FrO. The IGV control unit 63 controls the IGV opening so that the flow rate of air flowing into the compressor casing 14c becomes the flow rate corresponding to the fuel flow rate indicated by the fuel flow rate command FrO.

[0053] As described above, the target temperature calculator 66 of the temperature control system 65 uses function F1 to determine the target temperature of the hot water for the fuel flow rate indicated by the fuel flow rate command FrO. The temperature deviation calculator 67 of the temperature control system 65 subtracts the temperature detected by the thermometer 48 from the target temperature and outputs this value as the temperature deviation ΔT.

[0054] The PI controller 68 of the temperature control system 65 determines the opening correction amount for proportional and integral operation according to the temperature deviation ΔT, and outputs the operation amount corresponding to this opening correction amount as a valve command to the three-way valve 57.

[0055] The operation of the temperature control system 65 described above controls the operation of the three-way valve 57, thereby adjusting the amount of heat exchanged in the heat exchange amount adjustment process S2.

[0056] As mentioned above, the pressure control process S5 is performed when an operator or other user requests pressure correction. The pressure control system 70 of the control device 60 performs this pressure control process S5.

[0057] The pressure compensation mode button 71 of the pressure control system 70 accepts whether or not the operator wishes to perform pressure compensation. When the operator wishes to perform pressure compensation and presses the pressure compensation mode button 71, the pressure compensation mode button 71 outputs an ON signal, and the control device 60 enters pressure compensation mode.

[0058] The lower limit memory 72a stores the lower limit pressure Pa of the fuel (gaseous ammonia) flowing into the combustor 15. The upper limit memory 72b stores the upper limit Pb of the fuel (gaseous ammonia) flowing into the combustor 15.

[0059] The lower limit deviation calculator 73a of the pressure control system 70 calculates the deviation ΔPat between the lower limit pressure value Pa and the pressure detected by the pressure gauge 49. Specifically, the lower limit deviation calculator 73a subtracts the pressure detected by the pressure gauge 49 from the lower limit pressure value Pa and outputs this value as the lower limit deviation ΔPat. The upper limit deviation calculator 73b of the pressure control system 70 calculates the deviation ΔPbt between the upper limit pressure value Pb and the pressure detected by the pressure gauge 49. Specifically, the upper limit deviation calculator 73b subtracts the pressure detected by the pressure gauge 49 from the upper limit pressure value Pb and outputs this value as the upper limit deviation ΔPbt.

[0060] The lower limit deviation determiner 74a of the pressure control system 70 determines whether the lower limit deviation ΔPat is a positive value, in other words, whether the pressure detected by the pressure gauge 49 is less than the lower pressure limit value Pa, and outputs a statement to that effect. The upper limit deviation determiner 74b of the pressure control system 70 determines whether the upper limit deviation ΔPbt is a negative value, in other words, whether the pressure detected by the pressure gauge 49 is greater than the upper pressure limit value Pb, and outputs a statement to that effect.

[0061] The lower limit correction indicator 75a of the pressure control system 70 outputs an ONa signal indicating that temperature correction based on the lower pressure value Pa will be performed when the lower limit deviation ΔPat is a positive value and an ON signal is received from the pressure correction mode button 71. On the other hand, if the lower limit deviation ΔPat is not a positive value or an ON signal is not received from the pressure correction mode button 71, the lower limit correction indicator 75a outputs an OFFa signal indicating that temperature correction based on the lower pressure value Pa will not be performed. The upper limit correction indicator 75b of the pressure control system 70 outputs an ONb signal indicating that temperature correction based on the upper pressure value Pb will be performed when the upper limit deviation ΔPbt is a negative value and an ON signal is received from the pressure correction mode button 71. On the other hand, if the upper limit correction indicator 75b is not a negative value or an ON signal is not received from the pressure correction mode button 71, the upper limit correction indicator 75b outputs an OFFb signal indicating that temperature correction based on the upper pressure value Pb will not be performed.

[0062] The lower limit correction value calculator 77a of the pressure control system 70 receives the fuel flow rate command FrO and the lower limit deviation ΔPat as inputs. The lower limit correction value calculator 77a uses the function Fa shown below to calculate the lower limit correction value Ca corresponding to the fuel flow rate Fr indicated by the fuel flow rate command FrO and the lower limit deviation ΔPat (>0). This lower limit correction value Ca is a temperature correction value based on the pressure lower limit value Pa. Furthermore, this lower limit correction value Ca is a positive value. Fa:Ca = k × ΔPat / Fr In the above formula, k is the correction factor.

[0063] The upper limit correction value calculator 77b of the pressure control system 70 receives the fuel flow command FrO and the upper limit deviation ΔPbt as inputs. The upper limit correction value calculator 77b uses the function Fb shown below to determine the upper limit correction value Cb corresponding to the fuel flow rate Fr indicated by the fuel flow command FrO and the upper limit deviation ΔPbt (<0). This upper limit correction value Cb is a temperature correction value based on the pressure upper limit value Pb. Furthermore, this upper limit correction value Cb is a negative value. Fb:Cb = k × ΔPbt / Fr In the above formula, k is the correction factor.

[0064] When the first switch 78a of the pressure control system 70 receives an ONa signal from the lower limit correction indicator 75a, it outputs the lower limit correction value Ca calculated by the lower limit correction value calculator 77a. On the other hand, if the first switch 78a does not receive an ONa signal from the lower limit correction indicator 75a, it outputs 0 as the lower limit correction value. When the second switch 78b of the pressure control system 70 receives an ONb signal from the upper limit correction indicator 75b, it outputs the upper limit correction value Cb calculated by the upper limit correction value calculator 77b. On the other hand, if the second switch 78b does not receive an ONb signal from the upper limit correction indicator 75b, it outputs 0 as the upper limit correction value.

[0065] The first adder 79a of the pressure control system 70 adds a lower limit correction value Ca to the temperature deviation ΔT calculated by the temperature deviation calculator 67. The second adder 79b of the pressure control system 70 adds an upper limit correction value Cb to the temperature deviation ΔT calculated by the temperature deviation calculator 67.

[0066] The PI controller 68 of the pressure control system 70 determines the opening degree correction amount for proportional / integral operation according to (temperature deviation ΔT + lower limit correction value Ca) or (temperature deviation ΔT + upper limit correction value Cb), and outputs a valve command to the three-way valve 57 according to this opening degree correction amount.

[0067] The operation of the temperature control system 65 described above controls the operation of the three-way valve 57, thereby controlling the amount of heat exchanged in the heat exchange adjustment process S2 so that the pressure of the ammonia gas flowing into the gas turbine 10 remains within a predetermined pressure range.

[0068] The flow rate ratio adjustment step S2b of the heat exchange rate adjustment step S2 is performed by a three-way valve 57, which is a heat exchange rate regulator 56. The three-way valve 57 adjusts the flow rate ratio between the flow rate of the main high-temperature water and the flow rate of the branch high-temperature water after heat exchange in the heat exchange step S3, in accordance with instructions from the temperature control system 65, to merge the main high-temperature water and the branch high-temperature water after heat exchange in the heat exchange step S3. As a result, the merging high-temperature water is adjusted to a temperature sufficient to vaporize liquid ammonia in the vaporizer 45. In this embodiment, the boiling point of the liquid ammonia pressurized by the ammonia pump 44 is less than 60°C. Therefore, in this embodiment, the temperature of the hot water flowing into the vaporizer 45 is adjusted to approximately 90°C to 60°C.

[0069] Furthermore, when the three-way valve 57 receives instructions from the pressure control system 70, it adjusts the flow rate ratio between the flow rate of the main high-temperature water and the flow rate of the branch high-temperature water after heat exchange in the heat exchange process S3, thereby merging the main high-temperature water with the branch high-temperature water after heat exchange in the heat exchange process S3. As a result, the combined high-temperature water is adjusted to a temperature sufficient for vaporizing liquid ammonia in the vaporizer 45, and the pressure of the gaseous ammonia flowing into the gas turbine 10 is kept within a predetermined pressure range.

[0070] In the vaporization process S6, the liquid ammonia is vaporized by exchanging heat between the hot water, whose heat exchange rate with the medium has been adjusted in the heat exchange rate adjustment process S2, and the liquid ammonia within the vaporizer 45.

[0071] In the low-temperature water recovery process S7, the hot water cooled by heat exchange with liquid ammonia in the vaporizer 45 is returned to the hot water heater 52 via the low-temperature water line 51. The hot water that returns to the hot water heater 52 is heated by the exhaust gas. In other words, the hot water heating process S1 described above is performed in this hot water heater 52.

[0072] In the fuel supply process S8, gaseous ammonia, which is ammonia vaporized in the vaporizer 45, is supplied to the combustor 15 of the gas turbine 10 via the gaseous ammonia line 46.

[0073] As described above, in this embodiment, the hot water heated in the hot water heater 52 by heat exchange between the hot water and exhaust gas flows into the vaporizer 45 after its temperature has been adjusted. In the vaporizer 45, the temperature-adjusted hot water and liquid ammonia exchange heat, and the ammonia vaporizes. However, the temperature of the exhaust gas flowing through the waste heat recovery boiler 21 changes depending on the operating conditions of the gas turbine 10. Therefore, when the temperature of the exhaust gas changes, the temperature of the hot water heated in the hot water heater 52 also changes. However, in this embodiment, as mentioned above, the hot water heated in the hot water heater 52 flows into the vaporizer 45 after its temperature has been adjusted. Therefore, in this embodiment, even if the temperature of the exhaust gas changes, all of the liquid ammonia that flows into the vaporizer 45 can be easily and reliably converted into gaseous ammonia.

[0074] Furthermore, the amount of gaseous ammonia required by the gas turbine 10 also changes depending on the operating conditions of the gas turbine 10. In this embodiment, even if the amount of gaseous ammonia required by the gas turbine 10 changes, all of the liquid ammonia flowing into the vaporizer 45 can be easily and reliably converted into gaseous ammonia by changing the temperature of the hot water flowing into the vaporizer 45.

[0075] Therefore, in this embodiment, even if the operating conditions of the gas turbine 10 change, the amount of gaseous ammonia required by the gas turbine 10 can be easily and reliably obtained. Furthermore, in this embodiment, the responsiveness of the amount of gaseous ammonia produced to changes in the operating conditions of the gas turbine 10 can be improved.

[0076] As mentioned above, the flow rate of fuel supplied to the gas turbine 10 changes in accordance with the change in the required output PWr of the gas turbine 10. In this case, the amount of heat exchange between the fuel and hot water in the vaporizer 45 changes with the change in fuel flow rate. If the temperature of the hot water is adjusted according to the result of this change in heat exchange amount, it will take time from when the required output PWr changes until the amount of gaseous ammonia is produced. In this embodiment, the operating amount of the heat exchange rate regulator 56 is determined according to the required output PWr, so the time from when the required output PWr changes until the amount of gaseous ammonia is produced can be shortened. Therefore, in this embodiment, the responsiveness of the amount of gaseous ammonia produced to changes in the required output PWr can be improved from this viewpoint as well.

[0077] The pressure of the gaseous ammonia flowing into the gas turbine 10 must be within a predetermined pressure range; otherwise, stable combustion of the gaseous ammonia within the gas turbine 10 is not possible. In this embodiment, the pressure control system 70 controls the pressure of the gaseous ammonia flowing into the gas turbine 10 so that it remains within a predetermined pressure range. Therefore, in this embodiment, stable combustion of gaseous ammonia can be achieved within the gas turbine 10.

[0078] Here, we consider the case where liquid ammonia flows into the heat transfer tube 45p of the vaporizer 45, and hot water flows into the vaporizer casing 45c that covers the heat transfer tube 45p. In this case, the liquid ammonia becomes gaseous ammonia in the heat transfer tube 45p, and gaseous ammonia accumulates in a portion of the heat transfer tube 45p. As a result, the heat transfer area effective for heat exchange between liquid ammonia and hot water becomes smaller than the total heat transfer area of ​​the heat transfer tube 45p. Moreover, in this case, the heat transfer area effective for heat exchange between liquid ammonia and hot water changes in response to changes in the amount of gaseous ammonia produced. Therefore, in this case, it is difficult to control the amount of heat exchange between liquid ammonia and hot water, and it may not be possible to secure the required amount of gaseous ammonia produced.

[0079] On the other hand, in this embodiment, hot water flows into the heat transfer tubes 45p of the vaporizer 45, and liquid ammonia flows into the vaporizer casing 45c that covers the heat transfer tubes 45p. Therefore, in this embodiment, liquid ammonia that comes into contact with the outer surface of the heat transfer tubes 45p can move away from the outer surface of the heat transfer tubes 45p once it vaporizes. Therefore, in this embodiment, the heat transfer area effective for heat exchange between liquid ammonia and hot water can be made larger than in the previous case relative to the total heat transfer area of ​​the heat transfer tubes 45p. Moreover, in this embodiment, the heat transfer area effective for heat exchange between liquid ammonia and hot water does not substantially change with respect to changes in the amount of gaseous ammonia produced. Therefore, from this viewpoint as well, in this embodiment, the amount of heat exchange between liquid ammonia and hot water can be easily controlled, and the required amount of gaseous ammonia can be easily and reliably obtained.

[0080] Within the boiler casing 21c, the temperature of the exhaust gas decreases as it moves downstream. In this embodiment, the hot water heater 52 is located downstream of the economizer 21eco, which is the furthest downstream heat transfer tube among the multiple heat transfer tubes within the boiler casing 21c. Therefore, in this embodiment, the heat from the exhaust gas, which has cooled down, can be effectively utilized by the hot water heater 52.

[0081] "Second Embodiment" Next, a second embodiment of the gas turbine plant according to this disclosure will be described with reference to Figures 5 and 6.

[0082] The gas turbine plant of this embodiment, like the gas turbine plant of the first embodiment, includes a gas turbine 10, a denitrification device 20, a waste heat recovery boiler 21, a chimney 22, a steam turbine 23, a condenser 24, a pump 25, and a control device 60, as shown in Figure 5. Furthermore, the gas turbine plant of this embodiment includes a fuel supply equipment 40a that is different from the fuel supply equipment 40 of the first embodiment.

[0083] The fuel supply equipment 40a of this embodiment, like the fuel supply equipment 40 of the first embodiment, includes an ammonia tank 41, a liquid ammonia line 42, a liquid ammonia control valve 43a, a fuel control valve 43b, an ammonia pump 44, a vaporizer 45, a gaseous ammonia line 46, a hot water pump 54, a heat exchanger 55, a media line 58i, a media recovery line 58o, and a media flow rate regulator 59. Furthermore, the fuel supply equipment 40a of this embodiment includes a hot water line 50a that is different from the hot water line 50 of the first embodiment, and a heat exchange rate regulator 56a that is different from the heat exchange rate regulator 56 of the first embodiment.

[0084] The hot water line 50a of this embodiment, like the hot water line 50 of the first embodiment, includes a low-temperature water line 51 and a hot water heater 52. Furthermore, the hot water line 50a of this embodiment has a high-temperature water line 53a that is different from the high-temperature water line 53 of the first embodiment. The high-temperature water line 53 of the first embodiment has a branched high-temperature water line 53y, but the high-temperature water line 53a of this embodiment does not have this branched high-temperature water line 53y.

[0085] The heat exchanger 55 in this embodiment is located in the high-temperature water line 53a. Therefore, all of the high-temperature water from the hot water heater 52 flows into the heat exchanger 55 via the high-temperature water line 53a. The medium line 58i connected to this heat exchanger 55 is provided with a medium flow rate regulator 59, similar to the first embodiment. The heat exchange rate regulator 56a in this embodiment has this medium flow rate regulator 59.

[0086] In this embodiment, the control device 60 controls the operation of the medium flow regulator 59 when adjusting the temperature of the hot water.

[0087] Next, the fuel supply method for the gas turbine plant in this embodiment will be described according to the flowchart shown in Figure 6.

[0088] In the fuel supply method of this embodiment, the hot water heating step S1, heat exchange step S3, pressure control step S5, temperature control step S4, vaporization step S6, low-temperature water recovery step S7, and fuel supply step S8 are performed, similar to the fuel supply method of the first embodiment. In addition, in the fuel supply method of this embodiment, the pressure control step S5 is also performed in response to a request from the operator, similar to the fuel supply method of the first embodiment. Furthermore, in the fuel supply method of this embodiment, a heat exchange amount adjustment step S2X is performed, which is different from the heat exchange amount adjustment step S2 of the first embodiment.

[0089] In the heat exchange rate adjustment step S2X of this embodiment, similar to the heat exchange rate adjustment step S2 of the first embodiment, the amount of heat exchange between the high-temperature water from the hot water heater 52 and the medium flowing into the heat exchanger 55 is adjusted to adjust the temperature of the high-temperature water flowing into the vaporizer 45. However, the method of adjusting the amount of heat exchange in the heat exchange rate adjustment step S2X of this embodiment differs from the method of adjusting the amount of heat exchange in the heat exchange rate adjustment step S2 of the first embodiment. The heat exchange rate adjustment step S2X of this embodiment includes a medium flow rate adjustment step S2c.

[0090] In the medium flow rate adjustment process S2c, the medium flow rate regulator 59, acting as a heat exchange rate regulator 56a, operates based on instructions from the temperature control system 65 or pressure control system 70 of the control device 60. As a result, the flow rate of the medium flowing into the heat exchanger 55 is adjusted. Consequently, the amount of heat exchanged between the medium and the high-temperature water in the heat exchanger 55 is adjusted, thereby adjusting the temperature of the high-temperature water flowing into the vaporizer 45.

[0091] In this embodiment, the PI controller 68 of the temperature control system 65 determines the opening correction amount for proportional and integral operation according to the temperature deviation ΔT, and outputs the operation amount corresponding to this opening correction amount to the medium flow rate regulator 59. In addition, the PI controller 68 of the pressure control system 70 in this embodiment determines the opening correction amount for proportional and integral operation according to (temperature deviation ΔT + lower limit correction value Ca) or (temperature deviation ΔT + upper limit correction value Cb), and outputs the operation amount corresponding to this opening correction amount to the medium flow rate regulator 59.

[0092] In this way, the operation of the medium flow regulator 59 is controlled by the operation of the temperature control system 65 or the pressure control system 70, thereby controlling the amount of heat exchanged in the heat exchange amount adjustment process S2X.

[0093] As described above, in this embodiment as well, the hot water heated by the hot water heater 52 flows into the vaporizer 45 after temperature adjustment, so even if the operating conditions of the gas turbine 10 change, the amount of gaseous ammonia required by the gas turbine 10 can be easily obtained. Furthermore, in this embodiment, the responsiveness of the amount of gaseous ammonia produced to changes in the operating conditions of the gas turbine 10 can be improved.

[0094] Furthermore, since the high-temperature water line 53a of this embodiment does not have a branched high-temperature water line 53y, the line configuration is simpler than that of the gas turbine plant of the first embodiment, and equipment costs can be reduced.

[0095] In addition to the three-way valve 57, the heat exchange rate regulator 56 of the first embodiment may also have a medium flow rate regulator 59, similar to this embodiment.

[0096] "Variations of control devices" Next, a modified example of the control device described above will be explained with reference to Figure 7. In each of the above embodiments, the control device 60 can be set to pressure compensation mode. In this modified example, the control device 60a can be set to pressure lower limit control mode and pressure upper limit control mode in addition to this pressure compensation mode.

[0097] The control device 60a of this modified example has a fuel flow rate calculation unit 61, a fuel valve control unit 62, and an IGV control unit 63, similar to the control device 60 of each of the embodiments described above. Furthermore, the control device 60a of this modified example has a temperature control system 65a that is different from the temperature control system 65 of each of the embodiments described above, and a pressure control system 70a that is different from the pressure control system 70 of each of the embodiments described above.

[0098] The temperature control system 65a in this modified example has a target temperature calculator 66 and a temperature deviation calculator 67, similar to the temperature control system 65 in each of the above embodiments. Furthermore, the temperature control system 65a in this modified example has a PI control / switcher 68a that has the same function as the PI controller 68 in each of the above embodiments.

[0099] The temperature control system 65a in this modified example, like the temperature control system 65 in each of the embodiments described above, determines the opening correction amount for proportional and integral operation according to the temperature deviation ΔT between the target temperature and the temperature detected by the thermometer 48, and outputs the operation amount corresponding to this opening correction amount to the three-way valve 57 or the medium flow rate regulator 59, which serve as heat exchange rate regulators 56, 56a.

[0100] The pressure control system 70a of this modified example, like the pressure control system 70 of each of the embodiments described above, includes a pressure correction mode button 71, a lower limit memory 72a, an upper limit memory 72b, a lower limit deviation calculator 73a, an upper limit deviation calculator 73b, a lower limit deviation determiner 74a, an upper limit deviation determiner 74b, a lower limit correction indicator 75a, an upper limit correction indicator 75b, a lower limit correction value calculator 77a, an upper limit correction value calculator 77b, a first switch 78a, a second switch 78b, a first adder 79a, and a second adder 79b. The pressure control system 70a of this modified example further includes a PI control / switch 68a. The pressure control system 70a and the temperature control system 65a share this PI control / switch 68a.

[0101] The pressure control system 70a of this modified example further includes a lower limit control mode button 71a, an upper limit control mode button 71b, a lower limit control indicator 76a, and an upper limit control indicator 76b.

[0102] The lower limit control mode button 71a accepts whether the operator or other user desires pressure lower limit control. When the operator or other user desires pressure lower limit control and presses the lower limit control mode button 71a, the lower limit control mode button 71a outputs an ON signal, and the control device 60a enters pressure lower limit control mode. The upper limit control mode button 71b accepts whether the operator or other user desires pressure upper limit control. When the operator or other user desires pressure upper limit control and presses the upper limit control mode button 71b, the upper limit control mode button 71b outputs an ON signal, and the control device 60a enters pressure upper limit control mode.

[0103] The lower limit control indicator 76a outputs an ONac signal indicating that temperature control based on the pressure lower limit value Pa will be executed when the lower limit deviation ΔPat calculated by the lower limit deviation calculator 73a is a positive value and an ON signal is received from the lower limit control mode button 71a. On the other hand, if the lower limit deviation ΔPat is not a positive value or an ON signal is not received from the lower limit control mode button 71a, the lower limit control indicator 76a outputs an OFFac signal indicating that temperature control based on the pressure lower limit value Pa will not be executed. The upper limit control indicator 76b outputs an ONbc signal indicating that temperature control based on the pressure upper limit value Pb will be executed when the upper limit deviation ΔPbt calculated by the upper limit deviation calculator 73b is a negative value and an ON signal is received from the upper limit control mode button 71b. On the other hand, if the upper limit deviation ΔPbt is not a negative value or an ON signal is not received from the upper limit control mode button 71b, the upper limit control indicator 76b outputs an OFFbc signal indicating that temperature control based on the pressure upper limit value Pb will not be executed.

[0104] When the PI control / switch 68a receives an ONac signal from the lower limit control indicator 76a, it calculates an operating amount based on the lower limit deviation ΔPat calculated by the lower limit deviation calculator 73a, and outputs this operating amount to the three-way valve 57 or the medium flow rate regulator 59, which act as heat exchange rate regulators 56, 56a. The operating amount of the three-way valve 57 or the medium flow rate regulator 59 at this time is different from the operating amount when temperature correction is performed based on the pressure lower limit value Pa in pressure correction mode. Therefore, the operating amount of the three-way valve 57 or the medium flow rate regulator 59 changes depending on whether the operator or others select the pressure correction mode or the pressure lower limit control mode.

[0105] Furthermore, when the PI control / switch 68a receives an ONbc signal from the upper limit control indicator 76b, it calculates an operating amount based on the upper limit deviation ΔPbt calculated by the upper limit deviation calculator 73b, and outputs this operating amount to the three-way valve 57 or the medium flow rate regulator 59, which act as heat exchange rate regulators 56, 56a. The operating amount of the three-way valve 57 or the medium flow rate regulator 59 at this time is different from the operating amount when temperature correction is performed based on the pressure upper limit value Pb in pressure correction mode. Therefore, the operating amount of the three-way valve 57 or the medium flow rate regulator 59 changes depending on whether the operator or others select the pressure correction mode or the pressure upper limit control mode.

[0106] The buttons in the control device 60 in each of the above embodiments and in the control device 60a of this modified example may be physically existing buttons, or they may be virtually existing buttons on a display or the like.

[0107] "Other variations" In the above examples, cooling water is used as the medium for heat exchange with hot water. However, other fluids may be used as the medium as long as there is a certain temperature difference between them and the hot water.

[0108] In each of the embodiments and modifications described above, the hot water heater 52 heats the hot water to about 90°C, and then cools the hot water by exchanging heat with a medium such as cooling water to bring the temperature of the hot water to 90°C to 60°C. However, the temperature of the hot water may be adjusted by further heating the heated hot water in the hot water heater 52. In this case, the hot water heater 52 heats the hot water to, for example, about 50°C. Then, the heated hot water is further heated by exchanging heat with a medium, for example, one at about 100°C to 70°C, to bring the temperature of the hot water to 90°C to 60°C.

[0109] In each of the embodiments and modifications described above, the hot water heater 52 is positioned downstream of the economizer 21eco, which is the furthest downstream heat transfer tube among the multiple heat transfer tubes, within the boiler casing 21c. However, the hot water heater 52 may also be positioned within the boiler casing 21c so as to overlap with the furthest downstream heat transfer tube in the direction of exhaust gas flow.

[0110] The gas turbine 10 in each of the above embodiments and variations is a so-called single-shaft gas turbine. However, the gas turbine may also be a twin-shaft gas turbine. That is, the gas turbine may have a compressor, a combustor, a high-pressure turbine, and a low-pressure turbine. In this case, the compressor rotor and the high-pressure turbine rotor are connected to each other to form the first gas turbine rotor. The low-pressure turbine rotor forms the second gas turbine rotor and is not mechanically connected to the first gas turbine rotor.

[0111] The gas turbine plants of each embodiment and modification described above are combined cycle plants comprising a gas turbine 10, a heat recovery boiler 21, and a steam turbine 23. However, the gas turbine plant may also be a cogeneration plant comprising a gas turbine 10 and a heat recovery boiler 21, but without a steam turbine. In this case, the steam generated by the heat recovery boiler 21 is used, for example, within the factory.

[0112] Each of the above embodiments and modified gas turbine plants is equipped with a denitrification device 20. However, if the NOx concentration in the exhaust gas discharged from the gas turbine 10 meets environmental standards, the gas turbine plant may be a plant without a denitrification device.

[0113] "Addendum" The gas turbine plant in the above embodiments can be understood, for example, as follows:

[0114] (1) The gas turbine plant in the first embodiment is The system comprises a gas turbine 10 that burns fuel and is driven by the combustion gas produced by the combustion of the fuel, a waste heat recovery boiler 21 that generates steam using the heat of the exhaust gas from the gas turbine 10, and fuel supply equipment 40, 40a that can supply ammonia as fuel to the gas turbine 10. The fuel supply equipment 40, 40a includes a liquid ammonia line 42 connected to an ammonia tank 41 capable of storing liquid ammonia, hot water lines 50, 50a through which hot water can flow, a vaporizer 45 connected to the end of the liquid ammonia line 42 and capable of heating and vaporizing the liquid ammonia by exchanging heat between the hot water from the hot water lines 50, 50a and the liquid ammonia, a heat exchanger 55 capable of exchanging heat between the hot water in the hot water lines 50, 50a and a medium, heat exchange rate regulators 56, 56a that can adjust the amount of heat exchange between the hot water and the medium to adjust the temperature of the hot water flowing into the vaporizer 45, and a gaseous ammonia line 46 that can guide the gaseous ammonia, which is the ammonia vaporized in the vaporizer 45, to the gas turbine 10. The vaporizer 45 has an ammonia inlet 45ci, an ammonia outlet 45co, a hot water inlet 45pi, and a hot water outlet 45po. The liquid ammonia line 42 is connected to the ammonia inlet 45ci of the vaporizer 45. The gaseous ammonia line 46 is connected to the ammonia outlet 45co of the vaporizer 45. The hot water lines 50, 50a are located within the waste heat recovery boiler 21 and include a hot water heater 52 that heats the hot water by exchanging heat between the hot water and the exhaust gas, and high-temperature water lines 53, 53a that connect the hot water heater 52 to the hot water inlet 45pi of the vaporizer 45. The heat exchanger 55 is provided in the high-temperature water lines 53, 53a.

[0115] In this embodiment, the hot water heated in the hot water heater 52 by heat exchange between the hot water and exhaust gas flows into the vaporizer 45 after its temperature has been adjusted. In the vaporizer 45, the temperature-adjusted hot water and liquid ammonia exchange heat, causing the ammonia to vaporize. However, the temperature of the exhaust gas flowing through the waste heat recovery boiler 21 changes depending on the operating conditions of the gas turbine 10. Therefore, when the temperature of the exhaust gas changes, the temperature of the hot water heated in the hot water heater 52 also changes. However, in this embodiment, as mentioned above, the hot water heated in the hot water heater 52 flows into the vaporizer 45 after its temperature has been adjusted. Therefore, in this embodiment, even if the temperature of the exhaust gas changes, all of the liquid ammonia that flows into the vaporizer 45 can be easily converted into gaseous ammonia.

[0116] Furthermore, the amount of gaseous ammonia required by the gas turbine 10 also changes depending on the operating conditions of the gas turbine 10. In this embodiment, even if the amount of gaseous ammonia required by the gas turbine 10 changes, all of the liquid ammonia flowing into the vaporizer 45 can be easily converted into gaseous ammonia by changing the temperature of the hot water flowing into the vaporizer 45.

[0117] Therefore, in this embodiment, even if the operating conditions of the gas turbine 10 change, the amount of gaseous ammonia required by the gas turbine 10 can be easily obtained. Furthermore, in this embodiment, the responsiveness of the amount of gaseous ammonia produced to changes in the operating conditions of the gas turbine 10 can be improved.

[0118] (2) The gas turbine plant in the second embodiment is In the gas turbine plant according to the first embodiment, the hot water line 53 includes a main hot water line 53x connecting the hot water inlet 45pi of the vaporizer 45 to the hot water heater 52, and a branch hot water line 53y that branches off from the main hot water line 53x and is connected to the main hot water line 53x. The heat exchanger 55 is provided in the branch hot water line 53y. The heat exchange rate regulator 56 includes a flow rate ratio regulator that adjusts the ratio of the flow rate of hot water flowing between the branching point of the branch hot water line 53y and the connection point of the branch hot water line 53y in the main hot water line 53x, and the flow rate of hot water flowing through the branch hot water line 53y.

[0119] In this embodiment, the amount of heat exchange between the hot water and the medium can be adjusted by adjusting the ratio of the flow rate of hot water flowing between the branching point of the branched hot water line 53y and the connection point of the branched hot water line 53y in the main hot water line 53x, and the flow rate of hot water flowing through the branched hot water line 53y.

[0120] (3) The gas turbine plant in the third embodiment is In the gas turbine plant according to the first or second embodiment, the heat exchange rate regulator 56a has a medium flow rate regulator 59 that adjusts the flow rate of the medium flowing into the heat exchanger 55.

[0121] In this embodiment, the amount of heat exchange between the hot water and the medium can be adjusted by adjusting the flow rate of the medium flowing into the heat exchanger 55.

[0122] (4) The gas turbine plant in the fourth embodiment is In a gas turbine plant according to any one of the first to third embodiments described above, the vaporizer 45 has a heat transfer tube 45p through which hot water can flow, having a hot water inlet 45pi and a hot water outlet 45po, and a vaporizer casing 45c that covers the heat transfer tube 45p and is capable of temporarily storing the liquid ammonia. The vaporizer casing 45c has an ammonia inlet 45ci and an ammonia outlet 45co. The liquid ammonia line 42 is connected to the ammonia inlet 45ci of the vaporizer casing 45c, and the gaseous ammonia line 46 is connected to the ammonia outlet 45co of the vaporizer casing 45c.

[0123] When liquid ammonia flows into the heat transfer tube 45p and hot water flows into the vaporizer casing 45c that covers the heat transfer tube 45p, the liquid ammonia becomes gaseous ammonia within the heat transfer tube 45p, and gaseous ammonia accumulates in a portion of the heat transfer tube 45p. As a result, the effective heat transfer area for heat exchange between liquid ammonia and hot water becomes smaller than the total heat transfer area of ​​the heat transfer tube 45p. Moreover, in this case, the effective heat transfer area for heat exchange between liquid ammonia and hot water changes in response to changes in the amount of gaseous ammonia produced. Therefore, in this case, it is difficult to control the amount of heat exchange between liquid ammonia and hot water, and it may not be possible to secure the required amount of gaseous ammonia produced.

[0124] On the other hand, in this embodiment, hot water flows into the heat transfer tube 45p, and liquid ammonia flows into the vaporizer casing 45c that covers the heat transfer tube 45p. Therefore, in this embodiment, liquid ammonia that comes into contact with the outer surface of the heat transfer tube 45p can detach from the outer surface of the heat transfer tube 45p when it vaporizes. Therefore, in this embodiment, the heat transfer area effective for heat exchange between liquid ammonia and hot water can be made larger than in the previous case relative to the total heat transfer area of ​​the heat transfer tube 45p. Moreover, in this embodiment, the heat transfer area effective for heat exchange between liquid ammonia and hot water does not substantially change with respect to changes in the amount of gaseous ammonia produced. Therefore, in this embodiment, the amount of heat exchange between liquid ammonia and hot water can be easily controlled, and the required amount of gaseous ammonia can be easily obtained.

[0125] (5) The gas turbine plant in the fifth embodiment is In the gas turbine plant according to any one of the first to fourth embodiments described above, the waste heat recovery boiler 21 includes a boiler casing 21c through which exhaust gas from the gas turbine 10 flows, and a plurality of heat transfer tubes arranged within the boiler casing 21c through which water or steam flows. The plurality of heat transfer tubes are arranged in the direction of the exhaust gas flow within the boiler casing 21c. The hot water heater 52 is positioned within the boiler casing 21c at a location that overlaps with the heat transfer tube furthest downstream in the direction of the exhaust gas flow, or at a location further downstream, among the plurality of heat transfer tubes.

[0126] Within the boiler casing 21c, the temperature of the exhaust gas decreases as it moves downstream in the exhaust gas flow. In this embodiment, the heat from the cooled exhaust gas can be effectively utilized in the hot water heater 52.

[0127] (6) The gas turbine plant in the sixth embodiment is In a gas turbine plant according to any one of the first to fifth embodiments described above, the plant further includes control devices 60, 60a for controlling the operation of the heat exchange rate controllers 56, 56a. The control devices 60, 60a have a temperature control system 65, 65a that determines the amount of operation of the heat exchange rate controllers 56, 56a according to the requested output PWr from an external source to the gas turbine 10, and instructs the heat exchange rate controllers 56, 56a to perform the operation.

[0128] The flow rate of fuel supplied to the gas turbine 10 changes in accordance with the change in the required output PWr of the gas turbine 10. In this case, the amount of heat exchange between the fuel and hot water in the vaporizer 45 changes with the change in fuel flow rate. If the temperature of the hot water is adjusted according to the result of this change in heat exchange amount, it will take time from when the required output PWr changes until the amount of gaseous ammonia is produced. In this embodiment, the operating amount of the heat exchange rate regulators 56, 56a is determined according to the required output PWr, so the time from when the required output PWr changes until the amount of gaseous ammonia is produced can be shortened. In other words, in this embodiment, the responsiveness of the amount of gaseous ammonia produced to changes in the required output PWr can be improved.

[0129] (7) The gas turbine plant in the seventh embodiment is In the gas turbine plant according to the sixth embodiment, the control devices 60, 60a further include pressure control systems 70, 70a that determine the amount of operation of the heat exchange rate regulators 56, 56a so that the pressure of the gaseous ammonia flowing into the gas turbine 10 falls within a predetermined pressure range, and instruct the heat exchange rate regulators 56, 56a to perform the operation.

[0130] The pressure of the gaseous ammonia flowing into the gas turbine 10 must be within a predetermined pressure range; otherwise, stable combustion of the gaseous ammonia within the gas turbine 10 is not possible. In this embodiment, the pressure control systems 70 and 70a control the pressure of the gaseous ammonia flowing into the gas turbine 10 so that it remains within a predetermined pressure range. Therefore, in this embodiment, stable combustion of gaseous ammonia can be achieved within the gas turbine 10.

[0131] The fuel supply methods for the gas turbine plant in each of the above embodiments and modifications can be understood, for example, as follows. (8) The fuel supply method for a gas turbine plant in the eighth aspect is: A fuel supply method for a gas turbine plant comprising a gas turbine 10 that burns fuel and is driven by combustion gas produced by the combustion of the fuel, and a heat recovery boiler 21 that generates steam using the heat of exhaust gas from the gas turbine 10, comprising: a hot water heating step S1 in which hot water in a hot water heater 52 located in the heat recovery boiler 21 is heated by exchanging heat between the hot water and the exhaust gas inside the heat recovery boiler 21 but outside the hot water heater 52, and a heat exchange step in which the hot water heated in the hot water heating step S1 is heated and a medium is exchanged for heat. S3 is performed, along with heat exchange amount adjustment steps S2 and S2X which adjust the amount of heat exchange between the hot water heated in the hot water heating step S1 and the medium, vaporization step S6 which, in the vaporizer 45, heat exchanges the hot water, whose amount of heat exchange with the medium has been adjusted by the heat exchange amount adjustment steps S2 and S2X, with the liquid ammonia from the ammonia tank 41 storing the liquid ammonia to vaporize the liquid ammonia, and fuel supply step S8 which supplies the gaseous ammonia, which is the ammonia vaporized in the vaporization step S6, as fuel to the gas turbine 10. In the heat exchange amount adjustment steps S2 and S2X, the temperature of the hot water flowing into the vaporizer 45 is adjusted by adjusting the amount of heat exchange between the hot water and the medium in the heat exchange step S3.

[0132] In this embodiment, similar to the gas turbine plant in the first embodiment, the amount of gaseous ammonia required by the gas turbine 10 can be easily obtained even when the operating conditions of the gas turbine 10 change. Furthermore, in this embodiment as well, the responsiveness of the amount of gaseous ammonia produced to changes in the operating conditions of the gas turbine 10 can be improved.

[0133] (9) The fuel supply method for a gas turbine plant in the ninth embodiment is: In the fuel supply method for a gas turbine plant according to the eighth embodiment, the heat exchange amount adjustment step S2 includes a flow splitting step S2a for splitting the hot water heated in the hot water heating step S1 into main high-temperature water and branch high-temperature water, and a flow rate ratio adjustment step S2b. In the heat exchange step S3, the branch high-temperature water and the medium are subjected to heat exchange. In the flow rate ratio adjustment step S2b, the flow rate ratio between the flow rate of the main high-temperature water and the flow rate of the branch high-temperature water after heat exchange in the heat exchange step S3 is adjusted to merge the main high-temperature water and the branch high-temperature water after heat exchange in the heat exchange step S3.

[0134] In this embodiment, similar to the gas turbine plant in the second embodiment, the amount of heat exchange between the hot water and the medium can be adjusted.

[0135] (10) A fuel supply method for a gas turbine plant in the tenth embodiment is: In the fuel supply method for a gas turbine plant according to the eighth or ninth embodiment, the heat exchange amount adjustment step S2X includes a medium flow rate adjustment step S2c in which the flow rate of the medium that exchanges heat with the hot water in the heat exchange step S3 is adjusted.

[0136] In this embodiment, similar to the gas turbine plant in the third embodiment, the amount of heat exchange between hot water and the medium can be adjusted.

[0137] (11) A fuel supply method for a gas turbine plant in the eleventh embodiment is: In the fuel supply method for a gas turbine plant according to any one of the eighth to tenth embodiments described above, a temperature control step S4 is further executed to control the adjustment of the heat exchange amount in the heat exchange amount adjustment steps S2 and S2X according to the requested output PWr from an external source to the gas turbine 10.

[0138] In this embodiment, similar to the gas turbine plant in the sixth embodiment, the responsiveness of the amount of gaseous ammonia produced to changes in the required power output PWr can be improved.

[0139] (12) A fuel supply method for a gas turbine plant in the twelfth embodiment is: In the fuel supply method for a gas turbine plant according to the eleventh embodiment described above, a pressure control step S5 is further executed to control the adjustment of the heat exchange amount in the heat exchange amount adjustment steps S2 and S2X so that the pressure of the gaseous ammonia flowing into the gas turbine 10 falls within a predetermined pressure range.

[0140] In this embodiment, similar to the gas turbine plant in the seventh embodiment, gaseous ammonia can be stably burned within the gas turbine 10. [Explanation of Symbols]

[0141] 10: Gas Turbine 11: Gas turbine rotor 12: Intermediate casing 14: Compressor 14r: Compressor rotor 14c: Compressor casing 14i: Intake volume regulator (or IGV) 15: Combustor 16: Turbine 16r: Turbine rotor 16c: Turbine casing 20: Denitration equipment 21: Waste heat recovery boiler 21c: Boiler casing 21eco: Economizer 21eva: Evaporator 21s:Superheater 22: Chimney 23: Steam Turbine 24: Condenser 25: Pump 26: Water supply line 27: Main steam line 40,40a:Fuel supply equipment 41: Ammonia tank 42: Liquid Ammonia Line 43a: Liquid ammonia control valve 43b: Fuel control valve 44: Ammonia pump 45: Vaporizer 45c: Vaporizer casing 45ci: Ammonia inlet 45co: Ammonia outlet 45p: Heat transfer tube 45pi: Hot water inlet 45po: Hot water outlet 46: Gaseous ammonia line 48: Thermometer 49: Pressure gauge 50,50a: Hot water line 51: Low-temperature water line 52:Hot water heater 53,53a: High-temperature water line 53x: Main high-temperature water line 53y: Branch high-temperature water line 54: Hot water pump 55: Heat exchanger 55c: Heat exchanger casing 55p: Heat transfer tube 55pi: Media inlet 55po: Media outlet 56,56a: Heat exchange amount regulator 57: Three-way valve (or flow ratio regulator) 58i: Media Line 58o: Media collection line 59:Media flow regulator 60, 60a: Control device 61:Fuel flow rate calculation section 62: Fuel valve control unit 63: IGV Control Unit 65, 65a: Temperature control system 66:Target temperature calculator 67: Temperature deviation calculator 68: PI Controller 68a: PI control / switch 70,70a: Pressure control system 71: Pressure compensation mode button 71a: Lower limit control mode button 71b: Upper limit control mode button 72a: Lower limit memory 72b: Upper limit memory 73a: Lower limit deviation calculator 73b: Upper limit deviation calculator 74a: Lower limit deviation judger 74b: Upper limit deviation judger 75a: Lower limit correction indicator 75b: Upper limit correction indicator 76a: Lower limit control indicator 76b: Upper limit control indicator 77a: Lower limit correction value calculator 77b: Upper limit correction value calculator 78a: First changer 78b: Second switch 79a: First Adder 79b: Second adder

Claims

1. A gas turbine that burns fuel and is driven by the combustion gas produced by the combustion of the fuel, A waste heat recovery boiler capable of generating steam using the heat from the exhaust gas of the aforementioned gas turbine, A fuel supply system capable of supplying ammonia as the fuel to the gas turbine, Equipped with, The aforementioned fuel supply equipment is A liquid ammonia line connected to an ammonia tank capable of storing liquid ammonia, A high-temperature water line through which hot water heated by heat exchange with the exhaust gas can be flowed within the heat recovery boiler, A vaporizer connected to the liquid ammonia line, which can heat and vaporize the liquid ammonia by exchanging heat between the hot water from the high-temperature water line and the liquid ammonia, A heat exchanger provided in the aforementioned high-temperature water line, which is capable of exchanging heat between the hot water and the medium, A heat exchange rate regulator that can adjust the amount of heat exchange between the hot water and the medium to adjust the temperature of the hot water flowing into the vaporizer, A gaseous ammonia line that can guide gaseous ammonia, which is ammonia vaporized in the aforementioned vaporizer, to the gas turbine, Having, Gas turbine plant.

2. In the gas turbine plant according to claim 1, The high-temperature water line comprises a main high-temperature water line connecting the vaporizer and the waste heat recovery boiler, and a branch high-temperature water line that branches off from the main high-temperature water line and is connected to the main high-temperature water line. The heat exchanger is provided in the branched high-temperature water line, The heat exchange rate regulator includes a flow rate ratio regulator that adjusts the ratio between the flow rate of the hot water flowing between the branching point of the branched hot water line and the connection point of the branched hot water line in the main hot water line, and the flow rate of the hot water flowing through the branched hot water line. Gas turbine plant.

3. In the gas turbine plant according to claim 1 or 2, The heat exchange rate regulator includes a medium flow rate regulator that adjusts the flow rate of the medium flowing into the heat exchanger. Gas turbine plant.

4. In the gas turbine plant according to any one of claims 1 to 3, The aforementioned high-temperature water line is located within the waste heat recovery boiler and includes a hot water heater that heats the hot water by heat exchange with the exhaust gas. Gas turbine plant.

5. In the gas turbine plant according to any one of claims 1 to 4, The vaporizer has a hot water inlet and a hot water outlet, a heat transfer tube through which the hot water can flow, and a vaporizer casing that covers the heat transfer tube and is capable of temporarily storing the liquid ammonia. The vaporizer casing has an ammonia inlet and an ammonia outlet. The liquid ammonia line is connected to the ammonia inlet of the vaporizer casing, and the gaseous ammonia line is connected to the ammonia outlet of the vaporizer casing. Gas turbine plant.

6. In the gas turbine plant according to claim 4, The aforementioned heat recovery boiler comprises a boiler casing through which the exhaust gas from the gas turbine flows, and a plurality of heat transfer tubes arranged within the boiler casing through which water or steam flows. The plurality of heat transfer tubes are arranged in the direction of the exhaust gas flow within the boiler casing. The hot water heater is positioned within the boiler casing at a location that overlaps with the heat transfer tube furthest downstream in the direction of the exhaust gas flow, or at a location further downstream, among the plurality of heat transfer tubes. Gas turbine plant.

7. In the gas turbine plant according to any one of claims 1 to 6, Furthermore, it is equipped with a control device that controls the operation of the heat exchange rate regulator, The control device has a temperature control system that determines the amount of operation of the heat exchange rate controller in accordance with the output requested from the outside to the gas turbine, and instructs the heat exchange rate controller to perform the operation. Gas turbine plant.

8. In the gas turbine plant according to claim 7, The control device further includes a pressure control system that determines the amount of operation of the heat exchange rate regulator and instructs the heat exchange rate regulator to perform the operation so that the pressure of the gaseous ammonia flowing into the gas turbine falls within a predetermined pressure range. Gas turbine plant.

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