Gas turbine cogeneration system, method for retrofitting a gas turbine cogeneration system, and additional unit for a gas turbine cogeneration system

Abstract

To provide a gas turbine cogeneration system with a reduced amount of carbon dioxide emission, a method for modifying a gas turbine cogeneration system, and an add-on unit for a gas turbine cogeneration system.SOLUTION: A gas turbine cogeneration system comprises: a gas turbine including a combustor; an exhaust heat recovery boiler for generating boiler steam with exhaust gas exhausted from the gas turbine as a heat source; a water recovery device for recovering moisture from the exhaust gas by heat exchange between refrigerant water and the exhaust gas exhausted from the exhaust heat recovery boiler; and a fuel gas generation facility for generating gas turbine fuel gas to be supplied to the combustor, with industrial water (recovered water and supply water) including recovered water recovered by the water recovery device as at least one of raw materials.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a gas turbine cogeneration system, a method for retrofitting a gas turbine cogeneration system, and an additional unit for a gas turbine cogeneration system.

Background Art

[0002] In the gas turbine cogeneration system disclosed in Patent Document 1, a mixed gas containing ammonia gas and steam, and a fuel such as natural gas are supplied to a combustor of a gas turbine. The ammonia gas is generated from a liquid to be treated using exhaust gas discharged from an exhaust heat recovery boiler of the gas turbine cogeneration system as a heat source. The steam generated in the exhaust heat recovery boiler is supplied to steam utilization equipment.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The exhaust gas discharged from the exhaust heat recovery boiler contains moisture. If this moisture can be used as fuel for the gas turbine cogeneration system, it is possible to suppress the consumption of fossil fuels with a high carbon content and contribute to the realization of a carbon-neutral society.

[0005] An object of the present disclosure is to provide a gas turbine cogeneration system with reduced carbon dioxide emissions, a method for retrofitting a gas turbine cogeneration system, and an additional unit for a gas turbine cogeneration system.

Means for Solving the Problems

[0006] The gas turbine cogeneration system according to at least one embodiment of the present disclosure is A gas turbine including a combustor, an exhaust heat recovery boiler for generating boiler steam using the exhaust gas discharged from the gas turbine as a heat source, a water recovery device for recovering moisture from the exhaust gas by heat exchange between the exhaust gas discharged from the exhaust heat recovery boiler and refrigerant water, and fuel gas generation equipment for generating gas turbine fuel gas to be supplied to the combustor using industrial water containing recovered water recovered by the water recovery device as at least one of raw materials. It is provided with.

[0007] A method for retrofitting a cogeneration system according to an embodiment of the present disclosure is a method for retrofitting a gas turbine cogeneration system including a gas turbine including a combustor and an exhaust heat recovery boiler, a water recovery device addition step for adding a water recovery device for recovering moisture from the exhaust gas by heat exchange between the exhaust gas discharged from the exhaust heat recovery boiler and refrigerant water, and a fuel gas generation equipment addition step for adding fuel gas generation equipment for generating gas turbine fuel gas to be supplied to the combustor using industrial water containing recovered water recovered by the water recovery device as at least one of raw materials. It is provided with.

[0008] A retrofit unit for a gas turbine cogeneration system according to an embodiment of the present disclosure is a water recovery device for recovering moisture from the exhaust gas by heat exchange between the exhaust gas discharged from the exhaust heat recovery boiler and refrigerant water, and fuel gas generation equipment for generating gas turbine fuel gas to be supplied to the combustor of the gas turbine using industrial water containing recovered water recovered by the water recovery device as at least one of raw materials. It is provided with.

Effect of the Invention

[0009] According to the present disclosure, a gas turbine cogeneration system with reduced carbon dioxide emissions, a method for retrofitting a gas turbine cogeneration system, and a supplementary unit for a gas turbine cogeneration system can be provided.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5A

Figure 5B

Figure 5C

Figure 5D

Figure 5E

Figure 5F

Figure 6

Figure 7

Modes for Carrying Out the Invention

[0011] Hereinafter, some embodiments of the present disclosure will be described with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of the components described as embodiments or shown in the drawings are not intended to limit the scope of the present disclosure, but are merely illustrative examples. For example, expressions indicating relative or absolute arrangements such as "in a certain direction", "along a certain direction", "parallel", "orthogonal", "center", "concentric", or "coaxial" shall not only strictly represent such arrangements, but also represent tolerances, or states of relative displacement with angles or distances that provide the same function. For example, expressions indicating that things are in an equal state such as "identical", "equal", and "homogeneous" shall not only strictly represent an equal state, but also represent tolerances, or states where there are differences that provide the same function. For example, expressions representing shapes such as a square shape or a cylindrical shape shall not only represent the shapes such as a square shape or a cylindrical shape in a geometrically strict sense, but also represent shapes including concavo-convex portions, chamfered portions, etc. within a range where the same effect can be obtained. On the other hand, the expressions "comprising", "including", or "having" a component do not exclude the existence of other components. Note that the same reference numerals may be given to similar configurations and the description may be omitted.

[0012] <1. Overview of Gas Turbine Cogeneration System 10> FIG. 1 is a schematic diagram of a gas turbine cogeneration system 10 according to an embodiment of the present disclosure. In the following description, "gas turbine cogeneration system 10" may be simply abbreviated as "cogeneration system 10".

[0013] The cogeneration system 10 includes a cogeneration line 1, a water recovery system 40, and a fuel gas generation facility 80. The cogeneration system 10 of this example is realized by adding the water recovery system 40 and the fuel gas generation facility 80 to an existing cogeneration line 1. That is, the water recovery system 40 and the fuel gas generation facility 80 are additional units 4 for a gas turbine cogeneration system (hereinafter sometimes referred to as "additional unit 4"). The cogeneration system 10 according to other examples may be realized by newly installing the cogeneration line 1, the water recovery system 40, and the fuel gas generation facility 80 at the same time.

[0014] Cogeneration system 1 includes a gas turbine 9 including a combustor 3. The combustor 3 is configured to be supplied with fuel from a mixed fuel gas supply facility 79 and a starting fuel gas supply facility 77. Further, the cogeneration system 1 includes an exhaust heat recovery boiler 14 for generating boiler steam using the exhaust gas 13 discharged from the gas turbine 9 as a heat source, a makeup water tank 17 for storing makeup water which is water for supplying the exhaust heat recovery boiler 14, a water supply line 19 for guiding the makeup water from the makeup water tank 17 to the exhaust heat recovery boiler 14, a steam consumer 11 configured to be driven by the boiler steam discharged from the exhaust heat recovery boiler 14, an exhaust gas line 57 through which the exhaust gas 13 discharged from the exhaust heat recovery boiler 14 flows, and an exhaust line 29 for guiding the exhaust gas 13 flowing through the exhaust gas line 57 to an exhaust tower 30. An exhaust damper 31 is provided in the exhaust line 29. While the exhaust damper 31 is closed, the exhaust gas 13 does not flow through the exhaust line 29 and is guided to a water recovery system 40.

[0015] The water recovery system 40 includes an exhaust gas supply line 141 and a water recovery device 33. The exhaust gas supply line 141 is connected to the exhaust gas line 57 and the water recovery device 33, and while the exhaust damper 31 is closed, the exhaust gas 13 discharged from the exhaust heat recovery boiler 14 is guided to the water recovery device 33 by the exhaust gas supply line 141. The water recovery device 33 is configured to recover moisture from the exhaust gas 13 by heat exchange between the exhaust gas 13 and the refrigerant water described later. The water recovery system 40 further includes a water supply line 43 for supplying the recovered water containing the recovered moisture to the makeup water tank 17. Accordingly, the makeup water guided by the water supply line 19 to the exhaust heat recovery boiler 14 contains the recovered water.

[0016] The fuel gas generation facility 80 includes a pumping line 49 for pumping the makeup water from the water supply line 19, and a fuel gas generation unit 81 configured to receive the industrial water which is the makeup water pumped by the pumping line 49. The fuel gas generation unit 81 is configured to generate gas turbine fuel gas for supplying to the combustor 3 using the industrial water as at least one of the raw materials.

[0017] In some embodiments, the gas turbine fuel gas generated by the fuel gas generation unit 81 is supplied to the above-described mixed fuel gas supply facility 79 via the fuel gas supply line 88. More specifically, the fuel gas generation facility 80 further includes a gas mixing device 8, and the gas turbine fuel gas supplied by the fuel gas supply line 88 flows into this gas mixing device 8. Further, fossil fuel gas flows into the gas mixing device 8, and the gas mixing device 8 is configured to generate a mixed fuel gas obtained by mixing the gas turbine fuel gas and the fossil fuel gas. Further, the fuel gas generation facility 80 further includes a mixed fuel gas supply line 86 for supplying the mixed fuel gas to the mixed fuel gas supply facility 79. The mixed fuel gas supplied by the mixed fuel gas supply line 86 is configured to be supplied to the combustor 3 via the mixed fuel gas supply facility 79 and the mixed supply line 78 in sequence. Therefore, it is understood that the mixed fuel gas supply line 86 is configured to supply the mixed fuel gas to the combustor 3.

[0018] According to the above configuration, the moisture contained in the exhaust gas 13 is recovered by the water recovery device 33, and the industrial water containing the recovered water is utilized as at least one of the raw material substances of the gas turbine fuel gas. Since the supply amount of other fuel gases such as fossil fuel gas can be reduced by the amount of the gas turbine fuel gas supplied to the combustor 3, the gas turbine cogeneration system 10 can reduce the carbon dioxide emission amount. Further, the moisture contained in the exhaust gas 13 is utilized as the gas turbine fuel gas after being recovered by the water recovery device 33, and the moisture generated by the combustion of the gas turbine fuel gas is recovered again by the water recovery device 33. In this way, a substance constituting the moisture (more specifically, hydrogen as will be described later) realizes the circulating gas turbine cogeneration system 10, and the supply amount of the fossil fuel gas outside the system of the system can be reduced, contributing to carbon neutrality. The same advantages are also realized by adding the additional unit 4 to the existing cogeneration system 1.

[0019] Note that the present disclosure is not limited to the above-described embodiments. Off-gas may flow into the gas mixing device 8 instead of fossil fuel gas. In this case, the gas mixing device 8 mixes the gas turbine fuel gas and the off-gas to generate a mixed fuel gas. Alternatively, the fuel gas generation facility 80 may not include the gas mixing device 8 and the mixed fuel gas supply line 86. In this case, the fuel gas supply line 88 is configured to directly supply the gas turbine fuel gas to the combustor 3. In any of the embodiments, the above advantages can be obtained.

[0020] Further, according to the configuration in which the fuel gas generation facility 80 includes the gas mixing device 8 that mixes the gas turbine fuel gas and the fossil fuel gas, since the mixed fuel gas supplied to the combustor 3 contains the fossil fuel gas, it is possible to sufficiently secure the calorific value generated by the combustion of the combustor 3.

[0021] Hereinafter, the detailed configurations of the cogeneration system 1, the water recovery system 40, and the fuel gas generation facility 80 will be exemplified in order.

[0022] <2. Cogeneration System 1> FIG. 2 is a schematic diagram of a cogeneration system 1 according to an embodiment of the present disclosure. The gas turbine 9 of the cogeneration system 1 includes a compressor 16 for generating compressed air 7 from the compressor inlet air 6, a combustor 3 for burning the supplied fuel and heating the compressed air 7 to generate combustion gas 12, a turbine 2 for rotating using the combustion gas 12 discharged from the combustor 3 as a driving source, and a generator 5 connected to the turbine 2. The combustor 3 is a diffusion-type combustor as an example. The generator 5 is configured to generate electricity by being driven by the turbine 2.

[0023] The fuel supplied by the combustor 3 is the starting fuel gas supplied by the starting fuel gas supply facility 77 and the mixed fuel gas supplied by the mixed fuel gas supply facility 79. The cogeneration system 1 includes a starting supply line 76 for guiding the starting fuel gas from the starting fuel gas supply facility 77 to the combustor 3 and a mixed supply line 78 for guiding the mixed fuel gas from the mixed fuel gas supply facility 79 to the combustor 3.

[0024] An on-off valve 76A and an on-off valve 78A are respectively provided in the starting supply line 76 and the mixing supply line 78. By controlling the opening and closing of these on-off valves, the fuel supplied to the combustor 3 can be selectively switched between the starting fuel gas and the mixed fuel gas. More specifically, when the gas turbine 9 is started, the on-off valve 76A is opened and the on-off valve 78A is closed. As a result, the starting supply line 76 exclusively supplies the starting fuel gas to the combustor 3, and exclusive combustion of the starting fuel gas occurs in the combustor 3. After the start of the gas turbine 9 is completed, the on-off valve 76A is closed and the on-off valve 78A is opened. As a result, the supply of the starting fuel gas is terminated, and the mixing supply line 78 supplies the mixed fuel gas to the combustor 3. Hereinafter, the starting fuel gas and the mixed fuel gas may be collectively referred to as "fuel gas".

[0025] FIG. 3 is a schematic view showing a combustor 3 according to an embodiment of the present disclosure. The combustor 3 includes a combustor casing 23 formed in a cylindrical shape, a head end 24 provided at one end of the combustor casing 23, a fuel nozzle 25 provided at the head end 24, a cylindrical combustor liner 26 that separates unburned air and burned combustion gas 12, and a combustor tail cylinder 27 connected to the downstream side of the combustor liner 26. The fuel nozzle 25 is configured to inject the fuel gas supplied by the starting supply line 76 or the mixing supply line 78 into the inside of the combustor liner 26. Compressed air 7 is supplied to the combustor casing 23. Inside the combustor casing 23, the compressed air 7 flows toward the head end 24 side through an annular space formed outside the combustor liner 26. The compressed air 7 flowing through the annular space flows into the inside of the combustor liner 26 and mixes with the fuel gas injected by the fuel nozzle 25. The fuel gas burns inside the combustor liner 26, and a flame 28 is generated inside the combustor liner 26. The combustion gas 12 generated inside the combustor liner 26 is discharged from the combustor tail cylinder 27 and flows into the turbine 2.

[0026] Returning to FIG. 2, the exhaust heat recovery boiler 14 is configured to generate boiler steam from boiler feed water guided by the feed water line 19, using the exhaust gas 13, which is the combustion gas 12 discharged from the turbine 2, as a heat source. The cogeneration system 1 includes a steam supply pipe 21 for supplying the boiler steam discharged from the exhaust heat recovery boiler 14 to the steam demand unit 11. The steam demand unit 11 in this example is a steam turbine. The steam demand unit 11 according to other examples may be a steam turbine of a combined power generation plant or an industrial process device, etc.

[0027] Although not an essential component of the present disclosure, the cogeneration system 10 includes a steam extraction pipe 130 for supplying the boiler steam extracted from the steam supply pipe 21 to the combustor 3. The steam extraction pipe 130 illustrated in the figure includes an upstream steam pipe 131 for supplying the steam extracted from the steam supply pipe 21 to the head end 24 side in the combustor 3, and a downstream steam pipe 132 for supplying the extracted steam to the turbine 2 side in the combustor 3.

[0028] More specifically, as shown in FIG. 3, the upstream steam pipe 131 is configured to supply the extracted steam between the head end 24 and the combustor liner 26. By changing the opening degree of the upstream steam flow control valve 131A provided in the upstream steam pipe 131, the upstream steam supply amount, which is the flow rate of the boiler steam flowing through the upstream steam pipe 131, is adjusted. As the upstream steam supply amount increases, the effect of lowering the temperature of the flame zone is greater, so the amount of nitrogen oxides generated in the combustor 3 decreases. For example, when the proportion of fossil fuel gas in the gas turbine fuel gas is high, or when ammonia gas, which will be described later, is adopted as the gas turbine fuel gas supplied to the combustor 3, the amount of nitrogen oxides generated in the combustor 3 is high. In this regard, according to the above configuration, the generation of nitrogen oxides can be suppressed by the boiler steam supplied by the upstream steam pipe 131. Further, the boiler steam supplied to the combustor 3 is mixed into the exhaust gas 13 and then recovered as the moisture contained in the exhaust gas 13 by the water recovery device 33. Thereby, a sufficient amount of recovered water can be recovered, so that the fuel gas generation facility 80 (see FIG. 1) can generate a sufficient amount of gas turbine fuel gas.

[0029] Further, the downstream steam pipe 132 is configured to supply the extracted boiler steam to the downstream side of the combustor liner 26. By changing the opening degree of the downstream steam flow control valve 132A provided in the downstream steam pipe 132, the downstream steam supply amount, which is the flow rate of the boiler steam flowing through the downstream steam pipe 132, is adjusted. The greater the total amount of the upstream steam supply amount and the downstream steam supply amount, the greater the flow rate of the steam flowing into the turbine 2 to do work, and the greater the power generation amount of the generator 5, which is the output of the gas turbine 9. Note that the boiler steam supplied by the downstream steam pipe 132 is also recovered by the water recovery device 33 after being mixed into the exhaust gas 13.

[0030] Returning to FIG. 2, although not an essential component of the present disclosure, the steam extraction pipe 130 further includes a desuperheater 22 for lowering the temperature of the steam extracted from the steam supply pipe 21. The desuperheater 22 disposed upstream of the upstream steam pipe 131 and the downstream steam pipe 132 in the direction in which the boiler steam flows is configured such that, for example, a part of the boiler feed water supplied to the exhaust heat recovery boiler 14 flows in as cold water (see arrow B), and the boiler steam is cooled by the cold water being injected inside the desuperheater 22. The cooled steam flows through the upstream steam pipe 131 and the downstream steam pipe 132.

[0031] Although not an essential component of the present disclosure, the cogeneration system 1 includes a makeup water tank 17 for storing the recovered water containing the moisture recovered from the water recovery system 40 as boiler feed water, a water supply line 15 for supplying makeup water to the makeup water tank 17, a water supply line 19 connected to the makeup water tank 17 and the exhaust heat recovery boiler 14, and a water supply pump 18 provided in the water supply line 19. When the water supply pump 18 is driven, the boiler feed water stored in the makeup water tank 17 flows through the water supply line 19 and is supplied to the exhaust heat recovery boiler 14. It is preferable that the temperature of the boiler feed water supplied to the exhaust heat recovery boiler 14 is high. This is because the amount of heat required for the exhaust heat recovery boiler 14 to generate boiler steam is reduced, and the efficiency of the cogeneration system 10 is improved.

[0032] <3. Water Recovery System 40> FIG. 4 is a schematic view of a water recovery system 40 according to an embodiment of the present disclosure. The aforementioned water recovery device 33, which is a component of the water recovery system 40, is configured to recover moisture in the exhaust gas 13 as recovered water by bringing the exhaust gas 13 guided by the exhaust gas supply line 141 into gas-liquid contact with the chilled water. As a more detailed example, the water recovery device 33 includes a heat exchange container 135 into which the exhaust gas 13 and the chilled water flow, a water spraying device 34 for spraying the chilled water inside the heat exchange container 135, and a packing 35 located below the water spraying device 34 inside the heat exchange container 135. When the water recovery damper 59 provided in the exhaust gas supply line 141 is opened, the exhaust gas 13 flows from the exhaust gas supply line 141 into the heat exchange container 135. The chilled water sprayed by the water spraying device 34 adheres to the packing 35 and exchanges heat with the exhaust gas 13 flowing into the heat exchange container 135. As a result, the moisture in the exhaust gas 13 condenses. The recovered water containing the condensed moisture and the chilled water that has completed heat exchange falls and accumulates in the water storage tank 136 that constitutes the lower part of the heat exchange container 135. Note that the exhaust gas 13 from which the moisture has been recovered is discharged from the exhaust gas outlet provided at the upper part of the water recovery device 33.

[0033] The water recovery system 40 further includes a recovered water cooling device 36 for cooling the recovered water discharged from the water storage tank 136 of the water recovery device 33, a recovered water discharge line 39 for guiding the recovered water discharged from the water storage tank 136 of the water recovery device 33 to the recovered water cooling device 36, and a recovered water supply line 42 for guiding the cooled recovered water discharged from the recovered water cooling device 36 to the heat exchange container 135 as chilled water. The recovered water cooling device 36 in this example is configured to cool the recovered water with cooling water such as seawater. A cooling water supply pump 55 is provided in the cooling water supply line 41 for supplying the cooling water to the recovered water cooling device 36.

[0034] The water recovery system 40 further includes a water supply line 43 for guiding the recovered water to the makeup water tank 17. The water supply line 43 includes a high-temperature water supply line 44 and a low-temperature water supply line 47. The high-temperature water supply line 44 is connected to the recovered water discharge line 39 and is configured to guide the recovered water taken out from the recovered water discharge line 39 to the makeup water tank 17. The recovered water taken out from the recovered water discharge line 39 has a relatively high temperature because it has the heat recovered from the exhaust gas 13. The low-temperature water supply line 47 is connected to the recovered water supply line 42 and is configured to guide the recovered water taken out from the recovered water supply line 42 to the makeup water tank 17. The recovered water taken out from the recovered water supply line 42 has a relatively low temperature because it has been subjected to a cooling process by the recovered water cooling device 36.

[0035] The low-temperature water supply line 47 is provided with a water treatment device 46 which is a component of the water recovery system 40. The water treatment device 46 is configured to perform a process of removing impurities such as sulfur, for example, from the recovered water flowing through the low-temperature water supply line 47. The impurities are generated along with the combustion in the combustor 3 (see FIG. 3) and may be mixed into the exhaust gas 13. At least a part of these impurities is dissolved in the recovered water by the heat exchange between the exhaust gas 13 and the refrigerant water in the water recovery device 33. By removing the impurities contained in the recovered water by the water treatment device 46, it is suppressed that the boiler feed water stored in the makeup water tank 17 contains impurities. Generally, the lower the temperature of the water to be treated, the higher the treatment capacity of the water treatment device 46 for removing impurities. When the temperature of the recovered water is high, the ion exchange resin 146 constituting the water treatment device 46 may be damaged, and there is a risk that the treatment capacity for removing impurities may decrease.

[0036] A high-temperature feed water valve 48 is provided in the high-temperature feed water line 44, and a low-temperature feed water valve 45 is provided in the low-temperature feed water line 47. When a fuel gas, which may be LPG classified as clean energy, is supplied as the starting fuel gas of the gas turbine 9 to the combustor 3, the amount of impurities mixed in the exhaust gas 13 is less than the allowable value. In this case, the high-temperature feed water valve 48 is opened, and high-temperature recovered water that does not require impurity removal treatment flows into the makeup water tank 17 via the high-temperature feed water line 44 (at this time, the low-temperature feed water valve 45 is closed). Since the temperature of the boiler feed water supplied from the makeup water tank 17 to the exhaust heat recovery boiler 14 can be increased, the efficiency of the cogeneration system 10 is improved.

[0037] On the other hand, after the gas turbine 9 is started, when the mixed fuel gas is supplied to the combustor 3, depending on the type of the gas turbine fuel gas or the ratio of the fossil fuel gas contained in the mixed fuel gas, the amount of impurities mixed in the exhaust gas 13 may be equal to or more than the allowable value and less than the allowable upper limit value. In this case, the high-temperature feed water valve 48 is closed, the low-temperature feed water valve 45 is opened, and low-temperature recovered water that requires impurity removal treatment flows into the makeup water tank 17 via the water treatment device 46 provided in the low-temperature feed water line 47. Therefore, it is possible to avoid impurities from adhering to the devices constituting the cogeneration system 10, such as the feed water line 19 and the exhaust heat recovery boiler 14, and suppress the deterioration of the cogeneration system 10.

[0038] As described above, in the water recovery system 40 of this example, it is possible to switch the feed water line 43 of the recovered water sent to the makeup water tank 17 according to the amount of impurities contained in the fuel gas supplied to the combustor 3. When the amount of impurities contained in the exhaust gas 13 is equal to or more than the allowable upper limit value, the water recovery damper 59 is closed, and the exhaust damper 31 (see FIG. 2) is opened. As a result, the exhaust gas 13 is discharged from the exhaust tower 30 without being supplied to the water recovery system 40.

[0039] <4. Fuel Gas Generation Facility 80> Figs. 5A to 5F are schematic diagrams of fuel gas generation facilities 80A(80) to 80F(80) according to the first to sixth embodiments, respectively. The gas turbine fuel gas in the first embodiment is methane gas. The gas turbine fuel gases in the second and fourth embodiments are ammonia gas. The gas turbine fuel gases in the third, fifth, and sixth embodiments are hydrogen gas. In Figs. 5A to 5F, the cogeneration system 10 is illustrated as cogeneration systems 10A(10) to 10F(10).

[0040] <4-1. Fuel Gas Generation Facility 80A(80) According to the First Embodiment> As shown in Fig. 5A, the fuel gas generation unit 81A(81) of the fuel gas generation facility 80A includes a water electrolysis device 61 for subjecting industrial water to a water electrolysis process to generate hydrogen gas, a carbon dioxide recovery device 62 for recovering carbon dioxide gas from the exhaust gas 13 discharged from the water recovery device 33, a methane generation device 63 for generating methane gas from the hydrogen gas generated by the water electrolysis device 61 and the carbon dioxide gas recovered by the carbon dioxide recovery device 62, and a methane fuel gas supply line 88A for supplying the methane gas as a gas turbine fuel gas to the gas mixing device 8. The carbon dioxide recovery device 62 uses the boiler steam discharged from the steam demand unit 11 as a heat source in the recovery of carbon dioxide gas. The methane fuel gas supply line 88A is an example of the fuel gas supply line 88 (see Fig. 1).

[0041] The water electrolysis device 61 is connected to the water pumping line 49, and the industrial water flowing through the water pumping line 49 flows into the water electrolysis device 61. The water electrolysis process performed by the water electrolysis device 61 is, for example, a water electrolysis process. The hydrogen gas generated by this process is led to the methane generation device 63 by the hydrogen gas supply line 91, which is a component of the fuel gas generation facility 80A(80).

[0042] The carbon dioxide recovery device 62 is connected to the steam demand unit 11 by a boiler steam supply line 101 which is a component of the fuel gas generation facility 80A. The boiler steam discharged from the steam demand unit 11 flows into the carbon dioxide recovery device 62 via the boiler steam supply line 101. Also, the carbon dioxide recovery device 62 is connected to the exhaust gas outlet of the water recovery device 33 by an exhaust gas supply line 109 which is a component of the fuel gas generation facility 80A. The exhaust gas 13 that has completed heat exchange and is discharged from the water recovery device 33 flows into the carbon dioxide recovery device 62 via the exhaust gas supply line 109. The exhaust gas 13 that has passed through the carbon dioxide recovery device 62 is discharged into the atmosphere from the exhaust tower 38.

[0043] In the carbon dioxide recovery device 62 of this example, a chemical absorption method is adopted. More specifically, the exhaust gas 13 discharged from the water recovery device 33 is mixed with an absorption liquid such as an amine solution to dissolve the carbon dioxide in the exhaust gas 13 in the absorption liquid. Then, by heating the absorption liquid using boiler steam as a heat source, carbon dioxide gas is recovered from the absorption liquid. The temperature of the exhaust gas 13 before mixing with the absorption liquid is preferably relatively low. In this regard, the exhaust gas 13 discharged from the water recovery device 33 has been subjected to a certain degree of cooling treatment by heat exchange with the refrigerant water in the water recovery device 33. That is, the water recovery device 33 has both the function of recovering moisture from the exhaust gas 13 and the function of cooling the exhaust gas 13 for carbon dioxide recovery. Thereby, the moisture recovery process and the cooling process are carried out without waste, contributing to energy saving of the cogeneration system 10A. Note that in the carbon dioxide recovery device 62, instead of the chemical absorption method, a physical absorption method, a membrane separation method, or a cryogenic separation method may be adopted.

[0044] The carbon dioxide gas generated in the carbon dioxide recovery device 62 flows into the methane generation device 63 via the carbon dioxide supply line 162. The methane generation device 63 is configured to generate methane gas by reacting oxygen gas and carbon dioxide gas on the surface of a catalyst under high temperature and high pressure. Here, the above catalyst is a Ni-based catalyst such as LaNi5, or a Ru-based catalyst such as Ru - Al2O3.

[0045] In some embodiments, the methane gas generated by the methane generator 63 is supplied to the gas mixer 8 through the methane fuel gas supply line 88A. In other embodiments, the methane fuel gas supply line 88A may directly supply the methane gas as the gas turbine fuel gas to the combustor 3. In any of the embodiments, the hydrogen contained in the methane gas combines with oxygen in the combustor 3 to generate moisture. This moisture is recovered by the water recovery device 33 and then reused for the generation of methane gas. Also, the carbon dioxide gas generated by the combustion of the methane gas is absorbed by the carbon dioxide recovery device 62, and at least a part of it is reused for the generation of methane gas. That is, in the cogeneration system 10A, hydrogen and carbon circulate.

[0046] According to the configuration in which the fuel gas generation facility 80A includes the water electrolysis device 61, methane gas can be generated as the gas turbine fuel gas derived from hydrogen gas, and the cogeneration system 10A can reduce the carbon dioxide emission amount. Also, since the moisture generated by the combustion of the gas turbine fuel gas derived from hydrogen gas in the combustor 3 is recovered by the water recovery device 33, the amount of recovered water increases, and the generation amount of the gas turbine fuel gas also increases. Therefore, the dependence on other fuel gases such as fossil fuel gas outside the system can be reduced. In addition, hydrogen and carbon can be circulated within the cogeneration system 10A. Also, in the generation of carbon dioxide by the carbon dioxide recovery device 62, the heat of the boiler steam discharged from the steam demand unit 11 is utilized, so the cogeneration system 10A can also achieve energy saving.

[0047] Although not an essential component of the first embodiment, the fuel gas generation unit 81A may further include an oxygen gas supply line 64 for supplying the oxygen gas generated in the process of generating hydrogen gas by the water electrolysis device 61 to the combustor 3. The oxygen gas flowing through the oxygen gas supply line 64 mixes with the compressed air 7 in the combustor casing 23 (see FIG. 3) and then flows into the combustor liner 26 (see FIG. 3).

[0048] According to the configuration in which the oxygen gas supply line 64 is provided, by using the oxygen gas generated by the water decomposition device 61 as the oxidant of the combustor 3, the industrial water to be subjected to the water decomposition treatment can be utilized without waste.

[0049] <4-2. Fuel Gas Generation Facility 80B (80) According to the Second Embodiment> Referring to FIG. 5B, the configuration of the fuel gas generation facility 80B (80) is illustrated. In FIG. 5B, the same components as those described with reference to FIG. 5A are given the same reference numerals, and the description of these components may be omitted hereinafter.

[0050] The fuel gas generation unit 81B (81) of the fuel gas generation facility 80B includes the above-described water decomposition device 61. Further, the fuel gas generation unit 81B includes a nitrogen gas extraction device 66 for extracting nitrogen gas from the atmosphere, a first ammonia generation device 71 for generating ammonia from the hydrogen gas generated by the water decomposition device 61 and the nitrogen gas extracted by the nitrogen gas extraction device 66, and a first ammonia fuel gas supply line 88B for supplying the ammonia gas discharged from the first ammonia generation device 71 to the gas mixing device 8 as the gas turbine fuel gas. The first ammonia fuel gas supply line 88B is an example of the fuel gas supply line 88 (see FIG. 1). Hydrogen gas discharged from the water decomposition device 61 flows into the first ammonia generation device 71 via the hydrogen gas supply pipe 173.

[0051] The nitrogen gas extraction device 66 is configured to extract nitrogen gas from the atmosphere by pressure swing adsorption (PSA; Pressure Swing Adsorption). The nitrogen gas generated by the nitrogen gas extraction device 66 flows into the first ammonia generation device 71 via the nitrogen gas supply pipe 174.

[0052] The first ammonia generation device 71 is configured to generate ammonia from hydrogen gas and nitrogen gas by synthesis using a catalyst, and ammonia catalytic synthesis by the Haber Bosch process is employed. The electric power required for synthesis using the catalyst is provided by the electric power generated by the generator 5 (see FIG. 2). In addition to the electric power of cogeneration, electric power may be provided using renewable energy sources (such as solar power generation and wind power generation). The ammonia generated in the first ammonia generation device 71 is in a supercritical fluid state. The ammonia discharged from the first ammonia generation device 71 is in a gaseous state, and this ammonia gas is supplied to the gas mixing device 8 via the first ammonia fuel gas supply line 88B. Note that the first ammonia fuel gas supply line 88B may be configured to directly supply ammonia gas as gas turbine fuel gas to the combustor 3. In any of the embodiments, hydrogen contained in the ammonia gas combines with oxygen in the combustor 3 to generate moisture. This moisture is recovered by the water recovery device 33 and then reused for the generation of ammonia gas. That is, in the cogeneration system 10B, hydrogen circulates.

[0053] According to the configuration in which the fuel gas generation facility 80B includes the water decomposition device 61, ammonia gas derived from hydrogen gas can be supplied as gas turbine fuel gas to the combustor 3, and the cogeneration system 10B can reduce the carbon dioxide emission amount. Further, since the moisture generated by the combustion of ammonia gas derived from hydrogen gas in the combustor 3 is recovered by the water recovery device 33, the amount of recovered water increases, and the generation amount of gas turbine fuel gas also increases. Therefore, the dependence on other fuel gases such as fossil fuel gas outside the system can be reduced. In addition, hydrogen can be circulated within the cogeneration system 10B. Further, according to the configuration in which the fuel gas generation facility 80B includes the nitrogen gas extraction device 66 and the first ammonia generation device 71, by generating ammonia from hydrogen gas, the supply system of the gas turbine fuel gas can be made simpler. Specifically, since the boiling point of ammonia is higher than that of other liquid fuels such as hydrogen, the facility for storing ammonia in a liquid phase state can be simplified. A storage tank as such a storage facility may be arranged in the first ammonia fuel gas supply line 88B. Alternatively, a large vehicle or tanker that transports the ammonia generated by the first ammonia generation device 71 while storing it in a liquid phase state may be used.

[0054] Further, according to the configuration in which the fuel gas generation facility 80B includes the first ammonia fuel gas supply line 88B, since ammonia gas containing no carbon can be used as gas turbine fuel gas, the cogeneration system 10B can reduce the carbon dioxide emission amount.

[0055] Note that although not an essential component of the second embodiment, the fuel gas generation unit 81B may further include the oxygen gas supply line 64 described in the first embodiment. The advantages obtained by providing the oxygen gas supply line 64 are as described in the first embodiment.

[0056] <4-3. Fuel Gas Generation Facility 80C(80) According to the Third Embodiment> Referring to FIG. 5C, the configuration of the fuel gas generation facility 80C (80) is illustrated. In FIG. 5C, the same components as those described with reference to FIG. 5B are given the same reference numerals, and the description of these components may be omitted below.

[0057] The fuel gas generation unit 81C (81) of the fuel gas generation facility 80C includes a water decomposition device 61, a nitrogen gas extraction device 66, a nitrogen gas supply pipe 174, and a first ammonia generation device 71. The details of these components are as described in the second embodiment.

[0058] Instead of the first ammonia fuel gas supply line 88B, the fuel gas generation unit 81C includes an ammonia gas discharge line 175, a first hydrogen gas generation device 51, and a first hydrogen fuel gas supply line 88C. The ammonia gas discharge line 175 is connected to the first hydrogen gas generation device 51 and the gas mixing device 8. The first hydrogen fuel gas supply line 88C is connected to the first hydrogen gas generation device 51 and the gas mixing device 8. The first hydrogen fuel gas supply line 88C is an example of the fuel gas supply line 88 (see FIG. 1).

[0059] The first hydrogen gas generation device 51 is connected to the steam demand unit 11 via a boiler steam supply line 102. That is, the boiler steam discharged from the steam demand unit 11 flows into the first hydrogen gas generation device 51. The first hydrogen gas generation device 51 is configured to generate hydrogen gas from the ammonia gas discharged from the first ammonia generation device 71 using the boiler steam discharged from the waste heat recovery boiler 14 as a heat source. The first hydrogen gas generation device 51 in this example is configured to generate hydrogen gas by thermal decomposition of ammonia gas using a catalytic cracking reaction (cracking reaction). In this thermal decomposition, boiler steam is used as a heat source. Also, the catalyst used in the cracking reaction is a Ru-based catalyst.

[0060] The first hydrogen fuel gas supply line 88C illustrated in FIG. 5C is configured to supply the hydrogen gas generated by the first hydrogen gas generator 51 to the gas mixer 8 as gas turbine fuel gas. The first hydrogen fuel gas supply line 88C according to other examples may directly supply the hydrogen gas as gas turbine fuel gas to the combustor 3. In any of the embodiments, the hydrogen that constitutes the hydrogen gas combines with oxygen in the combustor 3, generating moisture. This moisture is recovered by the water recovery device 33 and then reused for the production of ammonia gas (i.e., the production of hydrogen gas). That is, in the cogeneration system 10C, hydrogen circulates.

[0061] According to the above configuration, since hydrogen gas that does not contain carbon is used as gas turbine fuel gas, the cogeneration system 10C can reduce the carbon dioxide emissions. The gas turbine fuel gas can be generated as hydrogen gas, and the cogeneration system 10C can reduce the carbon dioxide emissions. Also, since the moisture generated by the combustion of hydrogen gas as gas turbine fuel gas in the combustor 3 is recovered by the water recovery device 33, the amount of recovered water increases, and the production amount of gas turbine fuel gas also increases. Therefore, the dependence on other fuel gases such as fossil fuel gas outside the system can be reduced. In addition, hydrogen can be circulated within the cogeneration system 10C. Also, since hydrogen gas, which has a relatively high calorific value per unit weight, can be used as gas turbine fuel gas, the supply amount of other fuel gases such as fossil fuel gas outside the cogeneration system 10C can be reduced.

[0062] Note that the cogeneration system 10C includes a nitrogen gas extraction device 66, a first ammonia production device 71, and an oxygen gas supply line 64, similar to the cogeneration system 10B. The advantages of having these configurations are as described in the second embodiment, and detailed description is omitted to avoid duplication of explanation.

[0063] <4-4. Fuel gas generation facility 80D (80) according to the fourth embodiment> Referring to FIG. 5D, the configuration of the fuel gas generation facility 80D (80) is illustrated. In FIG. 5D, the same components as those described with reference to FIG. 5B are given the same reference numerals, and the description of these components may be omitted hereinafter.

[0064] The fuel gas generation unit 81D (81) of the fuel gas generation facility 80D includes a nitrogen gas extraction device 66 and a nitrogen gas supply pipe 174. These components are as described in the second embodiment.

[0065] The fuel gas generation unit 81D further includes a second ammonia generation device 72 connected to the pumping line 49 and the nitrogen gas supply pipe 174, and a second ammonia fuel gas supply line 88D connected to the second ammonia generation device 72 and the gas mixing device 8. The second ammonia fuel gas supply line 88D is an example of the fuel gas supply line 88 (see FIG. 1).

[0066] The second ammonia generation device 72 is configured to generate ammonia through electrolytic synthesis from the industrial water supplied by the pumping line 49 and the nitrogen gas supplied by the nitrogen gas supply pipe 174. In the electrolytic synthesis of this example, a solid electrolyte that separates water and nitrogen when a voltage is applied to them is used. Hydrogen ions generated by applying a voltage to water pass through the solid electrolyte and move to the nitrogen side. As a result, hydrogen and nitrogen combine to generate ammonia. Ammonia at the time of generation is in a gaseous state. Note that the power required for electrolytic synthesis is provided by the power generated by the generator 5 (see FIG. 2). In addition to the above power source, renewable power sources (such as solar power generation and wind power generation) may be used to provide power.

[0067] The second ammonia fuel gas supply line 88D is configured to supply ammonia gas discharged from the second ammonia generator 72 to the gas mixer 8 as gas turbine fuel gas. The second ammonia fuel gas supply line 88D according to another example may directly supply ammonia gas as gas turbine fuel gas to the combustor 3. In any of the embodiments, hydrogen contained in the ammonia gas combines with oxygen in the combustor 3 to generate moisture. This moisture is recovered by the water recovery device 33 and then reused for ammonia production. That is, in the cogeneration system 10D, hydrogen circulates.

[0068] According to the above configuration, since ammonia is generated through electrolytic synthesis, the number of steps required for generation can be reduced compared to the case of adopting the Haber-Bosch method. Therefore, the second ammonia generator 72 can generate ammonia in a simple process. Also, by using ammonia as the gas turbine fuel gas, the supply system of the gas turbine fuel gas can be made simpler (details are as described in the second embodiment). Further, since ammonia gas containing no carbon is used as the gas turbine fuel gas, the cogeneration system 10D can reduce the carbon dioxide emission amount.

[0069] In some embodiments, the fuel gas generation facility 80D (80) may further include an oxygen gas supply line 65 for supplying oxygen gas generated in the process of generating ammonia in the second ammonia generator 72 to the combustor 3. The oxygen gas flowing through the oxygen gas supply line 65 mixes with the compressed air 7 in the combustor casing 23 (see FIG. 3) and then flows into the combustor liner 26 (see FIG. 3). According to the above configuration, by using the oxygen gas generated in the second ammonia generator 72 as the oxidant of the combustor 3, the industrial water to be subjected to the water decomposition treatment can be utilized without waste.

[0070] <4-5. Fuel Gas Generation Facility 80E (80) According to the Fifth Embodiment> Referring to Fig. 5E, the configuration of the fuel gas generation facility 80E (80) is illustrated. In Fig. 5E, the same components as those described with reference to Fig. 5D are given the same reference numerals, and the description of these components may be omitted below.

[0071] The fuel gas generation section 81E (81) of the fuel gas generation facility 80E includes a nitrogen gas extraction device 66, a nitrogen gas supply pipe 174, and a second ammonia generation device 72. These components are as described in the fourth embodiment. Further, the fuel gas generation facility 80E (80) further includes an oxygen gas supply line 65. This component is also as described in the fourth embodiment.

[0072] The fuel gas generation section 81E includes an ammonia gas discharge line 176, a second hydrogen gas generation device 52, and a second hydrogen fuel gas supply line 88E (88). The ammonia gas discharge line 176 is connected to the second ammonia generation device 72 and the second hydrogen gas generation device 52. The ammonia gas discharge line 176 supplies the ammonia gas discharged from the second ammonia generation device 72 to the second hydrogen gas generation device 52. The second hydrogen fuel gas supply line 88E (88) is connected to the second hydrogen gas generation device 52 and the gas mixing device 8. The second hydrogen fuel gas supply line 88E is an example of the fuel gas supply line 88 (see Fig. 1).

[0073] The second hydrogen gas generation device 52 has the same configuration as the first hydrogen gas generation device 51. The second hydrogen gas generation device 52 is connected to the steam demand body 11 via a boiler steam supply line 102. And the second hydrogen gas generation device 52 is configured to generate hydrogen gas from the ammonia gas discharged from the second ammonia generation device 72 using the boiler steam discharged from the waste heat recovery boiler 14 as a heat source. Since the method of generating hydrogen gas is the same as that of the first hydrogen gas generation device 51 (see Fig. 5C), detailed description is omitted.

[0074] The second hydrogen fuel gas supply line 88E supplies the hydrogen gas generated by the second hydrogen gas generator 52 to the gas mixer 8 as the gas turbine fuel gas. Note that the second hydrogen fuel gas supply line 88E may be configured to directly supply the hydrogen gas as the gas turbine fuel gas to the combustor 3. In any of the embodiments, the hydrogen that constitutes the hydrogen gas combines with oxygen in the combustor 3, generating moisture. This moisture is recovered by the water recovery device 33 and then reused for the production of ammonia (i.e., the production of hydrogen gas). That is, in the cogeneration system 10E, hydrogen circulates.

[0075] According to the above configuration, since hydrogen gas with a relatively high calorific value per unit weight can be used as the gas turbine fuel gas, the supply amount of other fuel gases outside the cogeneration system 10E can be reduced. Also, the advantages of the fuel gas generation facility 80E including the second ammonia generator 72 are as described in the fourth embodiment, so detailed description is omitted. The advantages of the fuel gas generation facility 80E including the oxygen gas supply line 65 are also as described in the fourth embodiment, so detailed description is omitted.

[0076] <4-6. Fuel Gas Generation Facility 80F(80) According to the Sixth Embodiment> Referring to FIG. 5F, the configuration of the fuel gas generation facility 80F(80) is illustrated. The fuel gas generation unit 81F(81) of the fuel gas generation facility 80F includes the water decomposition device 61 described above. Further, the fuel gas generation unit 81F includes a hydrogen fuel gas supply line 88F(88) connected to the water decomposition device 61 and the gas mixer 8. The hydrogen fuel gas supply line 88F is configured to supply the hydrogen gas generated by the water decomposition device 61 to the gas mixer 8 as the gas turbine fuel gas. The hydrogen fuel gas supply line 88F is an example of the fuel gas supply line 88 (see FIG. 1). Note that the hydrogen fuel gas supply line 88F may directly supply the hydrogen gas to the combustor 3. In any of the embodiments, the hydrogen that constitutes the hydrogen gas combines with oxygen in the combustor 3, generating moisture. This moisture is recovered by the water recovery device 33 and then reused for the production of hydrogen gas. That is, in the cogeneration system 10E, hydrogen circulates.

[0077] According to the above configuration, since hydrogen gas with a relatively high calorific value per unit weight can be used as the gas turbine fuel gas, the supply amount of other fuel gases such as fossil fuel gas outside the system of the cogeneration system 10F can be reduced.

[0078] <4-7. Others> The fuel gas generation facilities 80A to 80F (80) according to the first to sixth embodiments may be installed individually, or at least any two or more of the fuel gas generation facilities 80A to 80F may be installed in combination. Further, in the fuel gas generation facilities 80B and 80D in which ammonia gas is adopted as the gas turbine fuel gas, it is preferable that the above-described upstream steam pipe 131 (see FIGS. 2 and 3) is provided. When efficiently operating a large gas turbine 9, the temperature of the combustion chamber formed inside the combustor liner 26 is high, and nitrogen oxides are likely to be generated during the combustion of ammonia gas. In this regard, by supplying boiler steam from the upstream steam pipe 131 to the head end 24 side of the combustor 3, the advantage of suppressing the generation amount of nitrogen oxides can be remarkably obtained.

[0079] <5. Modification method of the cogeneration system 10G> With reference to FIGS. 1, 6, and 7, a method for modifying the cogeneration system 10G, which is the cogeneration system 10 before modification, into the cogeneration system 10 will be described. FIG. 6 is a schematic diagram of the cogeneration system 10G according to an embodiment of the present disclosure. FIG. 7 is a flowchart showing the modification method of the cogeneration system 10G.

[0080] Prior to the description of the modification method, the cogeneration system 10G (10) will be described. The cogeneration system 10G does not include the additional unit 4 shown in FIG. 1 (that is, the water recovery system 40 and the fuel gas generation facility 80). Further, an exhaust damper 31 (see FIG. 1) is not provided in the exhaust line 29 of the cogeneration system 10G. By adding the additional unit 4 and the exhaust damper 31 to the cogeneration system 10G, the cogeneration system 10 is realized. The detailed modification method is as follows.

[0081] First, a water recovery system addition step (S11) of adding a water recovery system 40 including a water recovery device 33 is executed. Specifically (also refer to FIG. 4), the water recovery system 40 is installed, and the inlet of an exhaust gas supply line 141 is connected to the connection portion between an exhaust gas line 57 and an exhaust line 29. Also, a water supply line 43 is connected to a makeup water tank 17. That is, the outlets of a high-temperature water supply line 44 and a low-temperature water supply line 47 are connected to the makeup water tank 17.

[0082] Next, an exhaust damper addition step (S13) of adding an exhaust damper 31 to the exhaust line 29 is executed. Note that if the exhaust damper 31 is provided in the exhaust line 29 before the modification, S13 may be omitted.

[0083] Next, a fuel gas generation facility addition step (S15) of adding a fuel gas generation facility 80 is executed. Specifically, the inlet of a water pumping line 49 is connected to a water supply line 19, and the outlet of a mixed fuel gas supply line 86 (refer to FIG. 1) is connected to a mixed fuel gas supply facility 79. Thereby, the cogeneration system 10 is completed.

[0084] Note that when a fuel gas generation facility 80A (refer to FIG. 5A) is added, in S15, a step of connecting the exhaust gas outlet of the water recovery device 33 and a carbon dioxide recovery device 62 using an exhaust gas supply line 109 is additionally executed. Also, when a fuel gas generation facility 80C (refer to FIG. 5C) is added, in S15, a step of connecting a first hydrogen gas generation device 51 and a steam demand unit 11 using a boiler steam supply line 102 is additionally executed. Similarly, when a fuel gas generation facility 80E (refer to FIG. 5E) is added, in S15, a step of connecting a second hydrogen gas generation device 52 and a steam demand unit 11 using a boiler steam supply line 102 is additionally executed. Furthermore, when fuel gas generation facilities 80A, 80B, 80C, 80F (Figs. 5A, 5B, 5C, 5F) including a water decomposition device 61 are additionally installed, in S15, a step of connecting the water decomposition device 61 and the combustor 3 by an oxygen gas supply line 64 may be additionally executed.

[0085] The retrofit method of the cogeneration system 10G described above is executed by an operator, a robot arm operated by the operator, or a combination thereof. <6. Summary> The content described in several of the above-described embodiments is understood as follows, for example.

[0086] 1) The gas turbine cogeneration system (10) according to at least one embodiment of the present disclosure includes a gas turbine (9) including a combustor (3), an exhaust heat recovery boiler (14) for generating boiler steam using the exhaust gas (13) discharged from the gas turbine as a heat source, a water recovery device (33) for recovering moisture from the exhaust gas by heat exchange between the exhaust gas discharged from the exhaust heat recovery boiler and chilled water, and a fuel gas generation facility (80) for generating gas turbine fuel gas for supplying to the combustor using industrial water including recovered water recovered by the water recovery device as at least one of raw materials. It is provided with.

[0087] According to the configuration of 1) above, the moisture contained in the exhaust gas is recovered by the water recovery device, and the industrial water containing the recovered water is utilized as at least one of the raw material substances of the gas turbine fuel gas. Since the supply amount of other fuel gases such as fossil fuel gas can be reduced for the portion where the gas turbine fuel gas is supplied to the combustor, the gas turbine cogeneration system can reduce the carbon dioxide emission amount. Further, the moisture contained in the exhaust gas is recovered by the water recovery device and then used as the gas turbine fuel gas, and the moisture generated by the combustion of the gas turbine fuel gas is recovered again by the water recovery device. In this way, a gas turbine cogeneration system in which the substances constituting the moisture circulate is realized, the supply amount of the fossil fuel gas outside the system of the said system can be reduced, and it can contribute to carbon neutrality.

[0088] 2) In some embodiments, it is the gas turbine cogeneration system described in 1) above, The fuel gas generation facility further includes a water electrolysis device (61) for subjecting the industrial water to a water electrolysis treatment to generate hydrogen gas.

[0089] According to the configuration of 2) above, the gas turbine fuel gas as hydrogen gas or the gas turbine fuel gas derived from hydrogen gas can be generated, and the carbon dioxide emission amount can be reduced. Further, since the moisture generated by the combustion of the gas turbine fuel gas as hydrogen gas or the gas turbine fuel gas derived from hydrogen gas in the combustor is recovered by the water recovery device, the amount of the recovered water increases, and the generation amount of the gas turbine fuel gas also increases. Therefore, the dependence on other fuel gases outside the system can be reduced. In addition, hydrogen can be circulated within the cogeneration system.

[0090] 3) In some embodiments, it is the gas turbine cogeneration system described in 2) above, The fuel gas generation facility is a carbon dioxide recovery device (62) for recovering carbon dioxide from the exhaust gas discharged from the water recovery device by using the boiler steam discharged from the exhaust heat recovery boiler, and A methane generation device (63) for generating methane gas from the hydrogen gas generated by the water electrolysis device and the carbon dioxide recovered by the carbon dioxide recovery device, A methane fuel gas supply line (88A) for supplying the methane gas as the gas turbine fuel gas to the combustor, and further includes.

[0091] According to the configuration of 3) above, methane gas derived from hydrogen gas can be supplied to the combustor as the gas turbine fuel gas. In addition, since carbon dioxide contained in the exhaust gas is used for the generation of methane gas, the amount of carbon dioxide emissions can be reduced. Furthermore, since the heat of the boiler steam is used during the generation of carbon dioxide, energy savings are achieved.

[0092] 4) In some embodiments, it is the gas turbine cogeneration system described in 2) or 3) above, The fuel gas generation facility further includes a hydrogen fuel gas supply line (88F) for supplying the hydrogen gas generated by the water electrolysis device as the gas turbine fuel gas to the combustor.

[0093] According to the configuration of 4) above, hydrogen gas with a relatively high calorific value per unit weight can be used as the gas turbine fuel gas, so the supply amount of other fuel gases outside the gas turbine cogeneration system can be reduced.

[0094] 5) In some embodiments, it is the gas turbine cogeneration system described in any one of 2) to 4) above, The fuel gas generation facility A nitrogen gas extraction device (66) for extracting nitrogen gas from the atmosphere, A first ammonia generation device (71) for generating ammonia from the hydrogen gas generated by the water electrolysis device and the nitrogen gas extracted by the nitrogen gas extraction device, and further includes.

[0095] According to the configuration of 5) above, by generating ammonia from hydrogen gas, the supply system of the gas turbine fuel gas can be made simpler. More specifically, since the boiling point of ammonia is higher than that of other liquid fuels such as hydrogen, the equipment for storing the fuel of the gas turbine in a liquid phase can be simplified.

[0096] 6) In some embodiments, it is the gas turbine cogeneration system described in 5) above, The fuel gas generation facility further includes a first ammonia fuel gas supply line (88B) for supplying the ammonia gas discharged from the first ammonia generation device to the combustor as the gas turbine fuel gas.

[0097] According to the configuration of 6) above, since ammonia gas containing no carbon is used as the gas turbine fuel gas, the carbon dioxide emission amount can be reduced.

[0098] 7) In some embodiments, it is the gas turbine cogeneration system described in 5) above, The fuel gas generation facility A first hydrogen gas generation device (51) for generating hydrogen gas from the ammonia gas discharged from the first ammonia generation device using the boiler steam discharged from the waste heat recovery boiler as a heat source, And a first hydrogen fuel gas supply line (88C) for supplying the hydrogen gas generated by the first hydrogen gas generation device to the combustor as the gas turbine fuel gas And further includes.

[0099] According to the configuration of 7) above, since hydrogen gas having a relatively high calorific value per unit weight can be utilized as the gas turbine fuel gas, the supply amount of other fuel gases outside the gas turbine cogeneration system can be reduced.

[0100] 8) In some embodiments, it is the gas turbine cogeneration system described in any one of 2) to 7) above, It further includes an oxygen gas supply line (66) for supplying oxygen gas generated in the process of generating the hydrogen gas by the water decomposition device to the combustor.

[0101] According to the configuration of 8) above, by using the oxygen gas generated by the water decomposition device as an oxidant for the combustor, the industrial water to be subjected to the water decomposition treatment can be utilized without waste.

[0102] 9) In some embodiments, it is the gas turbine cogeneration system described in 1) above, wherein the fuel gas generation facility includes a nitrogen gas extraction device (66) for extracting nitrogen gas from the atmosphere, and a second ammonia generation device (72) for generating ammonia through electrolytic synthesis from the industrial water and the nitrogen gas extracted by the nitrogen gas extraction device. and further includes.

[0103] According to the configuration of 9) above, in order to generate ammonia through electrolytic synthesis, the second ammonia generation device can generate ammonia in a simple process. By using ammonia as the gas turbine fuel gas, the supply system of the gas turbine fuel gas can be made simpler. More specifically, since the boiling point of ammonia is higher than that of other liquid fuels such as hydrogen, the facilities for storing the fuel of the gas turbine in a liquid phase state can be simplified.

[0104] 10) In some embodiments, the gas turbine cogeneration system described in 9) above further includes an oxygen gas supply line (65) for supplying oxygen gas generated in the process of generating the ammonia by the second ammonia generation device to the combustor.

[0105] According to the configuration of 10) above, by using the oxygen gas generated by the second ammonia generation device as an oxidant for the combustor, the industrial water to be subjected to the water decomposition treatment can be utilized without waste.

[0106] 11) In some embodiments, there is provided a gas turbine cogeneration system according to 9) or 10) above, wherein the fuel gas generation facility further includes a second ammonia fuel gas supply line (88D) for supplying ammonia gas discharged from the second ammonia generation device to the combustor as the gas turbine fuel gas.

[0107] According to the configuration of 11) above, the same operational effects as those of 6) can be obtained.

[0108] 12) In some embodiments, there is provided a gas turbine cogeneration system according to any one of 9) to 11) above, wherein the fuel gas generation facility further includes a second hydrogen gas generation device (52) for generating hydrogen gas from ammonia gas discharged from the second ammonia generation device using the boiler steam discharged from the waste heat recovery boiler as a heat source, and a second hydrogen fuel gas supply line (88E) for supplying the hydrogen gas generated by the second hydrogen gas generation device to the combustor as the gas turbine fuel gas.

[0109] According to the configuration of 12) above, the same operational effects as those of 7) can be obtained.

[0110] 13) In some embodiments, there is provided a gas turbine cogeneration system according to any one of 1) to 12) above, wherein the fuel gas generation facility further includes a gas mixing device (8) for mixing the gas turbine fuel gas and the fossil fuel gas to generate a mixed fuel gas, and a mixed fuel gas supply line (86) for supplying the mixed fuel gas to the combustor.

[0111] According to the configuration of 13) above, since the mixed fuel gas supplied to the combustor contains the fossil fuel gas, it is possible to sufficiently ensure the calorific value generated during the combustion of the combustor.

[0112] 14) In some embodiments, the gas turbine cogeneration system according to any one of 1) to 13) above is further provided with a head-end side steam supply pipe (upstream side steam pipe 131) for supplying the boiler steam discharged from the waste heat recovery boiler to the head-end side in the combustor.

[0113] According to the configuration of 14) above, by injecting boiler steam in the combustor, the generation of nitrogen oxides in the combustor can be suppressed. Further, the injected boiler steam is mixed into the exhaust gas and then recovered by the water recovery device as moisture contained in the exhaust gas. Thereby, a sufficient amount of recovered water can be recovered, so that the fuel gas generation facility can generate a sufficient amount of gas turbine fuel gas.

[0114] 15) A method for retrofitting a gas turbine cogeneration system (10) according to at least one embodiment of the present disclosure is a method for retrofitting a gas turbine cogeneration system (10) including a gas turbine (9) including a combustor (3) and a waste heat recovery boiler (14), a water recovery device addition step (S11) for adding a water recovery device (33) for recovering moisture from the exhaust gas by heat exchange between the exhaust gas (13) discharged from the waste heat recovery boiler and the refrigerant water; a fuel gas generation facility addition step (S15) for adding a fuel gas generation facility (80) for generating gas turbine fuel gas by using industrial water containing the recovered water recovered by the water recovery device as at least one of raw materials and supplying it to the combustor and comprising.

[0115] According to the configuration of 15) above, the same operational effects as those of 1) above can be obtained.

[0116] 16) A retrofit unit (4) for a gas turbine cogeneration system according to at least one embodiment of the present disclosure is A water recovery device (33) for recovering moisture from the exhaust gas (13) discharged from the exhaust heat recovery boiler (14) by heat exchange between the exhaust gas and the refrigerant water, and a fuel gas generation facility (80) for generating gas turbine fuel gas for supplying industrial water containing the recovered water recovered by the water recovery device as at least one of the raw material substances to the combustor (3) of the gas turbine (9). It is provided with.

[0117] According to the configuration of the above (16), the same operational effects as those of the above (1) can be obtained.

Explanation of symbols

[0118] 1: Cogeneration system 2: Turbine 3: Combustor 4: Additional unit for gas turbine cogeneration system 4: Additional unit 5: Generator 6: Compressor inlet air 7: Compressed air 8: Gas mixing device 9: Gas turbine 10: Gas turbine cogeneration system (cogeneration system) 11: Steam demand unit 12: Combustion gas 13: Exhaust gas 14: Exhaust heat recovery boiler 21: Steam supply pipe 24: Head end 25: Fuel nozzle 26: Combustor liner 27: Combustor tail pipe 28: Flame 29: Exhaust line 30: Exhaust tower 31: Exhaust damper 33: Water recovery device 49: Water extraction line 51: First hydrogen gas generation device 52: Second hydrogen gas generation device 55: Cooling water supply pump 57: Exhaust gas line 59: Water recovery damper 61: Water decomposition device 62: Carbon dioxide recovery device 63: Methane generation device 64,65: Oxygen gas supply line 66: Nitrogen gas extraction device 71: First ammonia generation device 72: Second ammonia generation device 80: Fuel gas generation facility 81: Fuel gas generation section 86: Mixed fuel gas supply line 88: Fuel gas supply line 88A: Methane fuel gas supply line 88B: First ammonia fuel gas supply line 88C: First hydrogen fuel gas supply line 88D: Second ammonia fuel gas supply line 88E: Second hydrogen fuel gas supply line 88F: Hydrogen fuel gas supply line 91: Hydrogen gas supply line 101: Boiler steam supply line 102: Boiler steam supply line 109: Exhaust gas supply line 130: Steam extraction pipe 131: Upstream steam pipe 131A: Upstream steam flow control valve 132: Downstream steam pipe 132A: Downstream steam flow control valve 135: Heat exchange container 162: Carbon dioxide supply line 173: Hydrogen gas supply pipe 174: Nitrogen gas supply pipe 175,176: Ammonia gas discharge line

Claims

1. A gas turbine including a combustor, A waste heat recovery boiler for generating boiler steam using the exhaust gas discharged from the gas turbine as a heat source, A water recovery device for recovering moisture from the exhaust gas by heat exchange between the exhaust gas discharged from the waste heat recovery boiler and cooling water, Fuel gas generation equipment for generating gas turbine fuel gas to be supplied to the combustor using industrial water containing the recovered water recovered by the water recovery device as at least one of raw materials, A gas turbine cogeneration system comprising.

2. The fuel gas generation equipment further includes a water decomposition device for subjecting the industrial water to a water decomposition treatment to generate hydrogen gas. The gas turbine cogeneration system according to claim 1.

3. The fuel gas generation equipment, A carbon dioxide recovery device for recovering carbon dioxide from the exhaust gas discharged from the water recovery device using the boiler steam discharged from the waste heat recovery boiler, A methane generation device for generating methane gas from the hydrogen gas generated by the water decomposition device and the carbon dioxide recovered by the carbon dioxide recovery device, A methane fuel gas supply line for supplying the methane gas to the combustor as the gas turbine fuel gas, And further includes The gas turbine cogeneration system according to claim 2.

4. The fuel gas generation equipment further includes a hydrogen fuel gas supply line for supplying the hydrogen gas generated by the water decomposition device to the combustor as the gas turbine fuel gas. The gas turbine cogeneration system according to claim 2 or 3.

5. The fuel gas generation equipment, A nitrogen gas extraction device for extracting nitrogen gas from the atmosphere, A first ammonia production device for producing ammonia from the hydrogen gas generated by the water electrolysis device and the nitrogen gas extracted by the nitrogen gas extraction device Further comprising The gas turbine cogeneration system according to claim 2 or 3.

6. The fuel gas generation facility further includes a first ammonia fuel gas supply line for supplying ammonia gas discharged from the first ammonia production device to the combustor as the gas turbine fuel gas. The gas turbine cogeneration system according to claim 5.

7. The fuel gas generation facility A first hydrogen gas production device for producing hydrogen gas from ammonia gas discharged from the first ammonia production device using the boiler steam discharged from the waste heat recovery boiler as a heat source, and A first hydrogen fuel gas supply line for supplying the hydrogen gas generated by the first hydrogen gas production device to the combustor as the gas turbine fuel gas Further comprising The gas turbine cogeneration system according to claim 5.

8. Further provided with an oxygen gas supply line for supplying oxygen gas generated in the process of generating the hydrogen gas by the water electrolysis device to the combustor The gas turbine cogeneration system according to claim 2 or 3.

9. The fuel gas generation facility A nitrogen gas extraction device for extracting nitrogen gas from the atmosphere, and A second ammonia production device for producing ammonia through electrolytic synthesis from the industrial water and the nitrogen gas extracted by the nitrogen gas extraction device Further comprising The gas turbine cogeneration system according to claim 1.

10. Further comprising an oxygen gas supply line for supplying oxygen gas generated in the process of generating ammonia by the second ammonia generator to the combustor The gas turbine cogeneration system according to claim 9.

11. The fuel gas generation facility further includes a second ammonia fuel gas supply line for supplying ammonia gas discharged from the second ammonia generator to the combustor as the gas turbine fuel gas The gas turbine cogeneration system according to claim 9 or 10.

12. The fuel gas generation facility A second hydrogen gas generator for generating hydrogen gas from ammonia gas discharged from the second ammonia generator using the boiler steam discharged from the waste heat recovery boiler as a heat source, and A second hydrogen fuel gas supply line for supplying the hydrogen gas generated by the second hydrogen gas generator to the combustor as the gas turbine fuel gas And further includes The gas turbine cogeneration system according to claim 9 or 10.

13. The fuel gas generation facility A gas mixing device for mixing the gas turbine fuel gas and the fossil fuel gas to generate a mixed fuel gas, and A mixed fuel gas supply line for supplying the mixed fuel gas to the combustor And includes The gas turbine cogeneration system according to any one of claims 1 to 3.

14. Further comprising a head end side steam supply pipe for supplying the boiler steam discharged from the waste heat recovery boiler to the head end side of the combustor The gas turbine cogeneration system according to any one of claims 1 to 3.

15. A method for retrofitting a gas turbine cogeneration system comprising a gas turbine including a combustor and a heat recovery boiler, A water recovery device addition step of adding a water recovery device for recovering moisture from the exhaust gas by heat exchange between the exhaust gas discharged from the heat recovery boiler and the refrigerant water; A fuel gas generation facility addition step of adding a fuel gas generation facility for generating gas turbine fuel gas to be supplied to the combustor using industrial water containing recovered water recovered by the water recovery device as at least one of the raw materials; A method for retrofitting a gas turbine cogeneration system comprising the above steps.

16. A water recovery device for recovering moisture from the exhaust gas by heat exchange between the exhaust gas discharged from the heat recovery boiler and the refrigerant water; A fuel gas generation facility for generating gas turbine fuel gas to be supplied to the combustor of the gas turbine using industrial water containing recovered water recovered by the water recovery device as at least one of the raw materials; A retrofitting unit for a gas turbine cogeneration system comprising the above components.

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