Gas turbine heat and power cogeneration system, method for transforming gas turbine heat and power cogeneration system, and additional unit for gas turbine heat and power cogeneration system

Abstract

A gas turbine cogeneration system is provided with: a gas turbine including a combustor; an exhaust heat recovery boiler for generating boiler steam using 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 a fuel gas generation device for generating a gas turbine fuel gas to be supplied to the combustor using at least one of industrial water (recovered water amp; make-up water) containing recovered water recovered by the water recovery device as a starting material.

Description

Technical Field

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

[0002] This application claims priority based on Japanese Patent Application No. 2023-004504 filed with the Japan Patent Office on January 16, 2023, the content of which is incorporated herein by reference. Background Art

[0003] In the gas turbine combined heat and power system disclosed in Patent Document 1, a mixed gas containing ammonia and water vapor and a fuel such as natural gas are supplied to the burner of the gas turbine. Ammonia is generated from a liquid to be treated using the exhaust gas discharged from the heat recovery boiler of the gas turbine combined heat and power system as a heat source. The steam generated by the heat recovery boiler is supplied to steam utilization equipment.

[0004] Prior Art Documents

[0005] Patent Documents

[0006] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2022-067465 Summary of the Invention

[0007] Problems to be Solved by the Invention

[0008] The exhaust gas discharged from the heat recovery boiler contains moisture. If this moisture can be used as fuel for the gas turbine combined heat and power system, the consumption of fossil fuels with a high carbon content can be suppressed, and it is expected to contribute to the realization of a carbon-neutral society.

[0009] An object of the present disclosure is to provide a gas turbine combined heat and power system, a method for retrofitting a gas turbine combined heat and power system, and an additional unit for a gas turbine combined heat and power system that reduce the amount of carbon dioxide emissions.

[0010] Solutions to the Problems

[0011] The gas turbine combined heat and power system according to at least one embodiment of the present disclosure includes:

[0012] A gas turbine including a burner;

[0013] A heat recovery boiler for generating boiler steam using the exhaust gas discharged from the gas turbine as a heat source;

[0014] 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 refrigerant water; and

[0015] A fuel gas generation device for generating a gas turbine fuel gas for supply to the burner using, as at least one of raw material substances, industrial water containing recovered water recovered by the water recovery device.

[0016] 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 having a burner and a heat recovery boiler, the method for retrofitting the cogeneration system including the following steps:

[0017] 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 heat recovery boiler and refrigerant water; and

[0018] A fuel gas generation device addition step for adding a fuel gas generation device for generating a gas turbine fuel gas for supply to the burner using, as at least one of raw material substances, industrial water containing recovered water recovered by the water recovery device.

[0019] An addition unit for a gas turbine cogeneration system according to an embodiment of the present disclosure includes:

[0020] 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 refrigerant water; and

[0021] A fuel gas generation device for generating a gas turbine fuel gas for supply to the burner of the gas turbine using, as at least one of raw material substances, industrial water containing recovered water recovered by the water recovery device.

[0022] Advantages of the Invention

[0023] According to the present disclosure, it is possible to provide a gas turbine cogeneration system, a method for retrofitting a gas turbine cogeneration system, and an addition unit for a gas turbine cogeneration system with reduced carbon dioxide emissions. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a schematic diagram of a gas turbine cogeneration system according to an embodiment.

[0025] Figure 2 is a schematic diagram of a cogeneration system according to an embodiment.

[0026] Figure 3 is a schematic diagram of a burner according to an embodiment.

[0027] Figure 4 is a schematic diagram of a water recovery system according to an embodiment.

[0028] Figure 5A is a schematic diagram of a fuel gas generation device according to a first embodiment.

[0029] Figure 5B is a schematic diagram of a fuel gas generation device according to a second embodiment.

[0030] Figure 5C is a schematic diagram of a fuel gas generation device according to a third embodiment.

[0031] Figure 5D is a schematic diagram of a fuel gas generation device according to a fourth embodiment.

[0032] Figure 5E is a schematic diagram of a fuel gas generation device according to a fifth embodiment.

[0033] Figure 5F is a schematic diagram of a fuel gas generation device according to a sixth embodiment.

[0034] Figure 6 is a schematic diagram of a cogeneration system before modification according to an embodiment.

[0035] Figure 7 is a flowchart showing a method for modifying a cogeneration system according to an embodiment. Detailed Embodiments

[0036] Hereinafter, some embodiments of the present disclosure will be described with reference to the drawings. However, the dimensions, materials, shapes, and relative arrangements of the constituent parts described in the embodiments or shown in the drawings are not intended to limit the scope of the present disclosure thereto, but are merely illustrative examples.

[0037] For example, expressions indicating relative or absolute arrangements such as "in a certain direction", "along a certain direction", "parallel", "orthogonal", "center", "concentric", or "coaxial" not only strictly represent such arrangements, but also represent states in which relative displacements have occurred at angles or distances with tolerances or to such an extent as to achieve the same function.

[0038] For example, expressions indicating that things are in an equal state such as "the same", "equal", and "homogeneous" not only strictly represent the equal state, but also represent states in which there are tolerances or differences to such an extent as to achieve the same function.

[0039] For example, expressions indicating shapes such as a quadrilateral shape and a cylindrical shape not only represent the quadrilateral shape and the cylindrical shape in a strictly geometric sense, but also represent shapes including concavo-convex portions, chamfered portions, etc. within a range where the same effect can be obtained.

[0040] On the other hand, expressions such as "comprising", "including", or "having" a constituent element are not exclusive expressions that exclude the existence of other constituent elements.

[0041] It should be noted that sometimes the same constituent elements are marked with the same reference numerals and the description is omitted.

[0042] <1. Outline of the gas turbine combined heat and power system 10>

[0043] Figure 1 It is a schematic diagram of the gas turbine combined heat and power system 10 according to an embodiment of the present disclosure. In the following description, the "gas turbine combined heat and power system 10" is sometimes abbreviated as the "combined heat and power system 10".

[0044] The combined heat and power system 10 includes a combined heat and power system 1, a water recovery system 40, and a fuel gas generation device 80. The combined heat and power system 10 in this example is realized by adding the water recovery system 40 and the fuel gas generation device 80 to the existing combined heat and power system 1. That is to say, the water recovery system 40 and the fuel gas generation device 80 are additional units 4 for the gas turbine combined heat and power system (hereinafter sometimes referred to as the "additional unit 4"). The combined heat and power system 10 in other examples can also be realized by newly installing the combined heat and power system 1, the water recovery system 40, and the fuel gas generation device 80 at the same time.

[0045] The combined heat and power system 1 includes a gas turbine 9 including a burner 3. The burner 3 is configured to be supplied with fuel from a mixed fuel gas supply device 79 and a starting fuel gas supply device 77. In addition, the combined heat and power system 1 further 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 boiler feed water used for supplying water to the exhaust heat recovery boiler 14; a water supply pipeline 19 for guiding the boiler feed water from the makeup water tank 17 to the exhaust heat recovery boiler 14; a steam demand body 11 configured to be driven by the boiler steam discharged from the exhaust heat recovery boiler 14; an exhaust gas pipeline 57 through which the exhaust gas 13 discharged from the exhaust heat recovery boiler 14 flows; and an exhaust pipe 29 for guiding the exhaust gas 13 flowing in the exhaust gas pipeline 57 to an exhaust tower 30. An exhaust damper 31 is provided in the exhaust pipe 29. During the period when the exhaust damper 31 is closed, the exhaust gas 13 does not flow in the exhaust pipe 29 but is guided to the water recovery system 40.

[0046] The water recovery system 40 includes an exhaust gas supply pipeline 141 and a water recovery device 33. The exhaust gas supply pipeline 141 is connected to the exhaust gas pipeline 57 and the water recovery device 33. During the period when the exhaust gas damper 31 is closed, the exhaust gas 13 discharged from the exhaust heat recovery boiler 14 is guided to the water recovery device 33 through the exhaust gas supply pipeline 141. The water recovery device 33 is configured to recover moisture from the exhaust gas 13 through heat exchange between the exhaust gas 13 and the refrigerant water described later. The water recovery system 40 further includes a water supply pipeline 43 for supplying the recovered water containing the recovered moisture to the makeup water tank 17. Therefore, the boiler feed water guided by the water supply pipeline 19 to the exhaust heat recovery boiler 14 contains the recovered water.

[0047] The fuel gas generation device 80 includes a extraction pipeline 49 for extracting boiler feed water from the water supply pipeline 19, and a fuel gas generation unit 81 configured to receive the industrial water that is the boiler feed water extracted by the extraction pipeline 49. The fuel gas generation unit 81 is configured to generate a gas turbine fuel gas for supplying to the burner 3 using at least one of the industrial water as a raw material substance.

[0048] In some embodiments, the gas turbine fuel gas generated by the fuel gas generation unit 81 is supplied to the above-mentioned mixed fuel gas supply device 79 via the fuel gas supply pipeline 88. More specifically, the fuel gas generation device 80 further includes a gas mixing device 8 into which the gas turbine fuel gas supplied by the fuel gas supply pipeline 88 flows. Moreover, 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 device 80 includes a mixed fuel gas supply pipeline 86 for supplying the mixed fuel gas to the mixed fuel gas supply device 79. The mixed fuel gas supplied by the mixed fuel gas supply pipeline 86 is sequentially supplied to the burner 3 via the mixed fuel gas supply device 79 and the mixed supply pipeline 78. Therefore, it can be understood that the mixed fuel gas supply pipeline 86 is configured to supply the mixed fuel gas to the burner 3.

[0049] 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 effectively used as at least one of the raw material substances of the fuel gas for the gas turbine. The supply amount of other fuel gases such as fossil fuel gas can be reduced according to the amount of the fuel gas for the gas turbine supplied to the burner 3. Therefore, the gas turbine cogeneration system 10 can reduce the amount of carbon dioxide emissions. In addition, the moisture contained in the exhaust gas 13 is recovered by the water recovery device 33 and then used as the fuel gas for the gas turbine, and the moisture generated by the combustion of the fuel gas for the gas turbine is recovered again by the water recovery device 33. In this way, the gas turbine cogeneration system 10 in which the substances constituting the moisture (more specifically, hydrogen as described later) are circulated is realized, the supply amount of the fossil fuel gas outside the system of the system can be reduced, and it can contribute to carbon neutrality. By adding the additional unit 4 to the existing cogeneration system 1, the same advantages can also be achieved.

[0050] It should be noted that the present disclosure is not limited to the above-described embodiments. Alternatively, off gas may flow into the gas mixing device 8 instead of the fossil fuel gas. In this case, the gas mixing device 8 mixes the fuel gas for the gas turbine and the exhaust gas to generate a mixed fuel gas. Or, the fuel gas generation device 80 may not include the gas mixing device 8 and the mixed fuel gas supply pipeline 86. In this case, the fuel gas supply pipeline 88 is configured to directly supply the fuel gas for the gas turbine to the burner 3. In any of the embodiments, the above advantages can be obtained.

[0051] In addition, according to the configuration in which the fuel gas generation device 80 includes the gas mixing device 8 that mixes the fuel gas for the gas turbine and the fossil fuel gas, the fossil fuel gas is included in the mixed fuel gas supplied to the burner 3, so that the calorific value generated by the combustion of the burner 3 can be sufficiently ensured.

[0052] Hereinafter, the detailed configurations of the cogeneration system 1, the water recovery system 40, and the fuel gas generation device 80 will be sequentially exemplified.

[0053] <2. Cogeneration System 1>

[0054] Figure 2 It 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 burner 3 for burning the supplied fuel and heating the compressed air 7 to a high temperature to generate combustion gas 12; a turbine 2 for rotating by using the combustion gas 12 discharged from the burner 3 as a driving source; and a generator 5 connected to the turbine 2. The burner 3 is a diffusion type burner as an example. The generator 5 is configured to generate electricity by the driving of the turbine 2.

[0055] The fuel supplied by the burner 3 is the starting fuel gas supplied by the starting fuel gas supply device 77 and the mixed fuel gas supplied by the mixed fuel gas supply device 79. The cogeneration system 1 includes: a starting supply pipeline 76 for guiding the starting fuel gas from the starting fuel gas supply device 77 to the burner 3; and a mixed supply pipeline 78 for guiding the mixed fuel gas from the mixed fuel gas supply device 79 to the burner 3.

[0056] On-off valves 76A and 78A are respectively provided in the starting supply pipeline 76 and the mixed supply pipeline 78. By controlling the opening and closing of these on-off valves, the fuel supplied to the burner 3 is selectively switched to the starting fuel gas or the mixed fuel gas. More specifically, when the gas turbine 9 starts up, the on-off valve 76A is opened and the on-off valve 78A is closed. Thereby, the starting supply pipeline 76 specifically supplies the starting fuel gas to the burner 3, and exclusive combustion of the starting fuel gas occurs in the burner 3. After the start-up of the gas turbine 9 is completed, the on-off valve 76A is closed and the on-off valve 78A is opened. Thereby, the supply of the starting fuel gas ends, and the mixed supply pipeline 78 supplies the mixed fuel gas to the burner 3. Hereinafter, the starting fuel gas and the mixed fuel gas are sometimes collectively referred to as "fuel gas".

[0057] Figure 3 It is a schematic diagram of the burner 3 showing an embodiment of the present disclosure. The burner 3 includes: a burner housing 23 formed in a cylindrical shape; a head end 24 provided at one end of the burner housing 23; a fuel nozzle 25 provided at the head end 24; a cylindrical burner liner 26 for separating unburned air and burned combustion gas 12; and a burner tail tube 27 connected to the downstream side of the burner liner 26. The fuel nozzle 25 is configured to inject the fuel gas supplied by the starting supply pipeline 76 or the mixed supply pipeline 78 into the interior of the burner liner 26. Compressed air 7 is supplied to the burner housing 23. Inside the burner housing 23, the compressed air 7 flows toward the head end 24 side through an annular space formed outside the burner liner 26. The compressed air 7 flowing through the annular space flows into the interior of the burner liner 26 and mixes with the fuel gas injected by the fuel nozzle 25. The fuel gas burns inside the burner liner 26, and a flame 28 is generated inside the burner liner 26. The combustion gas 12 generated inside the burner liner 26 is discharged from the burner tail tube 27 and flows into the turbine 2.

[0058] Return Figure 2, the heat recovery boiler 14 is configured to generate boiler steam from the boiler water guided through the water supply pipeline 19 using the combustion gas 12 discharged from the turbine 2, i.e., the exhaust gas 13, as a heat source. The cogeneration system 1 includes: a steam supply pipe 21 for supplying the boiler steam discharged from the heat recovery boiler 14 to the steam demand body 11. The steam demand body 11 in this example is a steam turbine. The steam demand body 11 in other examples may also be a steam turbine of a combined power generation device or an industrial process device, etc.

[0059] 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 burner 3. Figure 2 The steam extraction pipe 130 exemplified in 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 burner 3; and a downstream steam pipe 132 for supplying the extracted steam to the turbine 2 side in the burner 3.

[0060] More specifically, as Figure 3 shown, the upstream steam pipe 131 is configured to supply the extracted steam between the head end 24 and the burner 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 in the upstream steam pipe 131, can be adjusted. The greater the increase in the upstream steam supply amount, the greater the effect of reducing the temperature of the flame zone, and thus the amount of nitrogen oxides generated in the burner 3 is reduced. For example, when the proportion of fossil fuel gas in the gas turbine fuel gas is high, or when ammonia described later is used as the gas turbine fuel gas supplied to the burner 3, the amount of nitrogen oxides generated in the burner 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. In addition, after the boiler steam supplied to the burner 3 is mixed into the exhaust gas 13, it is recovered as the moisture contained in the exhaust gas 13 by the water recovery device 33. Thus, a sufficient amount of recovered water can be recovered, so that the fuel gas generation device 80 (refer to Figure 1 ) can generate a sufficient amount of gas turbine fuel gas.

[0061] In addition, the downstream steam pipe 132 is configured to supply the extracted boiler steam to the downstream side of the burner 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 in the downstream steam pipe 132, can be 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 operate, and the greater the power generation amount of the generator 5, which is the output of the gas turbine 9. It should be noted that the boiler steam supplied by the downstream steam pipe 132 is also recovered by the water recovery device 33 after being mixed with the exhaust gas 13.

[0062] Return Figure 2 , although not an essential component of the present disclosure, the steam extraction pipe 130 further includes a cooler 22 for reducing the temperature of the steam extracted from the steam supply pipe 21. The cooler 22 disposed upstream of the upstream steam pipe 131 and the downstream steam pipe 132 in the flow direction of the boiler steam is configured to flow a part of the boiler feed water supplied to the heat recovery boiler 14 as cold water (see arrow B), and cools the boiler steam by injecting the cold water inside the cooler 22. The cooled steam flows in the upstream steam pipe 131 and the downstream steam pipe 132.

[0063] , although not an essential component of the present disclosure, the cogeneration system 1 includes: a makeup water tank 17 that stores the recovered water containing the water 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 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 heat recovery boiler 14. Preferably, the temperature of the boiler feed water supplied to the heat recovery boiler 14 is high. This is because: the heat required for the heat recovery boiler 14 to generate boiler steam is reduced, and the efficiency of the cogeneration system 10 is improved.

[0064] <3. Water Recovery System 40>

[0065] Figure 4It is a schematic diagram of the 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 the 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 refrigerant 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 refrigerant water flow; a spraying device 34 for spraying the refrigerant water inside the heat exchange container 135; and a filler 35 located below the 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 into the heat exchange container 135 from the exhaust gas supply line 141. The refrigerant water sprayed by the spraying device 34 adheres to the filler 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 refrigerant water that has completed heat exchange falls and is stored in the water storage tank 136 that forms the lower part of the heat exchange container 135. It should be noted that the exhaust gas 13 from which the moisture has been recovered is discharged from the exhaust gas outlet provided in the upper part of the water recovery device 33.

[0066] 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 refrigerant water. The recovered water cooling device 36 in this example is configured to cool the recovered water by cooling water, and this cooling water can be, for example, seawater or the like. A cooling water supply pump 55 is provided in the cooling water supply line 41 for supplying cooling water to the recovered water cooling device 36.

[0067] 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 the heat recovered from the exhaust gas 13 and thus has a relatively high temperature. 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 been subjected to the cooling treatment by the recovered water cooling device 36 and thus has a relatively low temperature.

[0068] A water treatment device 46, which is a component of the water recovery system 40, is provided in the low-temperature water supply pipeline 47. The water treatment device 46 is configured to treat the recovered water flowing in the low-temperature water supply pipeline 47, for example, to remove impurities such as sulfur. Impurities are generated along with the combustion in the burner 3 (refer to Figure 3 ), and sometimes mix into the exhaust gas 13. At least a part of the impurities dissolve in the recovered water through 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, the water treatment device 46 can inhibit the impurities from being contained in the boiler feed water stored in the makeup water tank 17. Generally, the lower the temperature of the water to be treated, the higher the impurity removal treatment capacity in the water treatment device 46. When the temperature of the recovered water is high, the ion exchange resin 146 constituting the water treatment device 46 may be damaged, and the impurity removal treatment capacity may decrease.

[0069] A high-temperature water supply on-off valve 48 is provided in the high-temperature water supply pipeline 44, and a low-temperature water supply on-off valve 45 is provided in the low-temperature water supply pipeline 47. When the fuel gas, which can be LPG (Liquefied Petroleum Gas), a clean energy classified as such, is supplied as the starting fuel gas of the gas turbine 9 to the burner 3, the amount of impurities mixed into the exhaust gas 13 is less than the allowable value. In this case, the high-temperature water supply on-off valve 48 is opened, and the high-temperature recovered water that does not require impurity removal treatment flows into the makeup water tank 17 via the high-temperature water supply pipeline 44 (at this time, the low-temperature water supply on-off valve 45 has been closed). The temperature of the boiler feed water supplied from the makeup water tank 17 to the heat recovery boiler 14 can be increased, so the efficiency of the cogeneration system 10 is improved.

[0070] On the other hand, after the gas turbine 9 is started and the mixed fuel gas is supplied to the burner 3, depending on the type of the gas turbine fuel gas or the proportion of the fossil fuel gas contained in the mixed fuel gas, sometimes the amount of impurities mixed into the exhaust gas 13 is greater than or equal to the allowable value and less than the allowable upper limit value. In this case, the high-temperature water supply on-off valve 48 is closed, and the low-temperature water supply on-off valve 45 is opened. The 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 water supply pipeline 47. Therefore, impurities can be prevented from adhering to the equipment constituting the cogeneration system 10, such as the water supply pipeline 19 and the heat recovery boiler 14, and the deterioration of the cogeneration system 10 can be inhibited.

[0071] In this way, in the water recovery system 40 of this example, the water supply pipeline 43 for the recovered water transported to the makeup water tank 17 can be switched according to the amount of impurities contained in the fuel gas supplied to the burner 3. It should be noted that when the amount of impurities contained in the exhaust gas 13 is greater than or equal to the allowable upper limit value, the water recovery air damper 59 is closed, and the exhaust air damper 31 (refer to Figure 2is opened. As a result, the exhaust gas 13 is not supplied to the water recovery system 40, but is discharged from the exhaust tower 30.

[0072] <4. Fuel gas generation equipment 80>

[0073] Figures 5A - 5F are schematic diagrams of the fuel gas generation equipment 80A(80) - 80F(80) of the first to sixth embodiments respectively. The fuel gas for the gas turbine in the first embodiment is methane gas. The fuel gas for the gas turbine in the second and fourth embodiments is ammonia gas. The fuel gas for the gas turbine in the third, fifth, and sixth embodiments is hydrogen gas. In Figures 5A - 5F the cogeneration system 10 is illustrated as the cogeneration systems 10A(10) - 10F(10).

[0074] <4-1. Fuel gas generation equipment 80A(80) of the first embodiment>

[0075] As Figure 5A shown, the fuel gas generation unit 81A(81) of the fuel gas generation equipment 80A includes: a water decomposition device 61 for performing water decomposition treatment on industrial water to generate hydrogen; 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 generated by the water decomposition device 61 and the carbon dioxide gas recovered by the carbon dioxide recovery device 62; and a methane fuel gas supply pipeline 88A for supplying methane gas as the fuel gas for the gas turbine to the gas mixing device 8. The carbon dioxide recovery device 62 uses the boiler steam discharged from the steam demand body 11 as a heat source in the recovery of carbon dioxide gas. The methane fuel gas supply pipeline 88A is an example of the fuel gas supply pipeline 88 (refer to Figure 1 ).

[0076] The water decomposition device 61 is connected to the extraction pipeline 49, and the industrial water flowing through the extraction pipeline 49 flows into the water decomposition device 61. The water decomposition treatment performed in the water decomposition device 61 is, as an example, electrolytic water treatment. The hydrogen generated by this treatment is guided to the methane generation device 63 through a hydrogen supply pipeline 91 which is a component of the fuel gas generation equipment 80A(80).

[0077] The carbon dioxide recovery device 62 is connected to the steam demand body 11 through the boiler steam supply pipeline 101 which is a component of the fuel gas generation device 80A. The boiler steam discharged from the steam demand body 11 flows into the carbon dioxide recovery device 62 through the boiler steam supply pipeline 101. In addition, the carbon dioxide recovery device 62 is connected to the exhaust gas outlet of the water recovery device 33 through the exhaust gas supply pipeline 109 which is a component of the fuel gas generation device 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 through the exhaust gas supply pipeline 109. The exhaust gas 13 passing through the carbon dioxide recovery device 62 is discharged from the exhaust tower 38 to the atmosphere.

[0078] 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 amine liquid, and the carbon dioxide in the exhaust gas 13 is dissolved in the absorption liquid. Then, the absorption liquid is heated using the boiler steam as a heat source, thereby recovering carbon dioxide gas from the absorption liquid. Preferably, the temperature of the exhaust gas 13 before mixing with the absorption liquid is a relatively low temperature. In this regard, the exhaust gas 13 discharged from the water recovery device 33 is subjected to a certain degree of cooling treatment through heat exchange with the refrigerant water in the water recovery device 33. That is to say, 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 treatment and the cooling treatment can be carried out without waste, contributing to the energy saving of the cogeneration system 10A. It should be noted that in the carbon dioxide recovery device 62, a physical absorption method, a membrane separation method, or a cryogenic separation method may also be adopted instead of the chemical absorption method.

[0079] The carbon dioxide gas generated by the carbon dioxide recovery device 62 flows into the methane generation device 63 through the carbon dioxide supply pipeline 162. The methane generation device 63 is configured to generate methane gas by reacting oxygen and carbon dioxide gas on the surface of a catalyst under high temperature and high pressure. Here, the above-mentioned catalyst is a Ni-based catalyst such as LaNi5 or a Ru-based catalyst such as Ru-Al2O3, etc.

[0080] In some embodiments, the methane gas generated by the methane generation device 63 is supplied to the gas mixing device 8 through the methane fuel gas supply pipeline 88A. In other embodiments, the methane fuel gas supply pipeline 88A may also directly supply the methane gas, which is the fuel gas for the gas turbine, to the burner 3. In any of the embodiments, the hydrogen contained in the methane gas combines with oxygen in the burner 3 to generate moisture. After being recovered by the water recovery device 33, the moisture is reused for the generation of methane gas. In addition, the carbon dioxide gas generated by the combustion of the methane gas is also 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 to say, in the combined heat and power system 10A, hydrogen and carbon are recycled.

[0081] According to the configuration in which the fuel gas generation device 80A includes the water decomposition device 61, methane gas can be generated as the fuel gas for the gas turbine derived from hydrogen, and the combined heat and power system 10A can reduce the carbon dioxide emission. In addition, the moisture generated by the combustion of the fuel gas for the gas turbine derived from hydrogen in the burner 3 is recovered by the water recovery device 33. Therefore, the amount of recovered water increases, and the generation amount of the fuel gas for the gas turbine 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 recycled within the system of the combined heat and power system 10A. In addition, in the generation of carbon dioxide in the carbon dioxide recovery device 62, the heat of the boiler steam discharged from the steam demand body 11 is utilized. Therefore, the combined heat and power system 10A can also pursue energy conservation.

[0082] It should be noted that although it is not an essential component of the first embodiment, the fuel gas generation unit 81A may further include an oxygen supply pipeline 64 for supplying the oxygen generated during the generation of hydrogen in the water decomposition device 61 to the burner 3. The oxygen flowing through the oxygen supply pipeline 64 is mixed with the compressed air 7 in the burner housing 23 (refer to Figure 3 ), and then flows into the burner liner 26 (refer to Figure 3 ).

[0083] According to the configuration provided with the oxygen supply pipeline 64, by using the oxygen generated in the water decomposition device 61 as the oxidant of the burner 3, the industrial water to be subjected to the water decomposition treatment can be effectively utilized without waste.

[0084] <4-2. Fuel Gas Generation Device 80B (80) of the Second Embodiment>

[0085] Refer to Figure 5B , an example shows the configuration of the fuel gas generation device 80B (80). In Figure 5B , for those related to the reference Figure 5AThe same reference numerals are used for the same components as described above, and the description of these components may be omitted hereinafter.

[0086] The fuel gas generation unit 81B (81) of the fuel gas generation device 80B includes the above-described water decomposition device 61. Further, the fuel gas generation unit 81B also includes: a nitrogen extraction device 66 for extracting nitrogen from the atmosphere; a first ammonia generation device 71 for generating ammonia from the hydrogen generated by the water decomposition device 61 and the nitrogen extracted by the nitrogen extraction device 66; and a first ammonia fuel gas supply pipeline 88B for supplying the ammonia discharged from the first ammonia generation device 71 as a gas turbine fuel gas to the gas mixing device 8. The first ammonia fuel gas supply pipeline 88B is an example of the fuel gas supply pipeline 88 (see Figure 1 ). The hydrogen discharged from the water decomposition device 61 flows into the first ammonia generation device 71 via the hydrogen supply pipe 173.

[0087] The nitrogen extraction device 66 is configured to extract nitrogen from the atmosphere by pressure swing adsorption (PSA; Pressure Swing Adsorption). The nitrogen generated by the nitrogen extraction device 66 flows into the first ammonia generation device 71 via the nitrogen supply pipe 174.

[0088] The first ammonia generation device 71 is configured to generate ammonia from hydrogen and nitrogen gas by synthesis using a catalyst, and employs ammonia catalyst synthesis using the Haber Bosch process. The electric power required for the synthesis using the catalyst is supplied by the electric power generated by the generator 5 (see Figure 2 ). In addition to the electric power generated by combined heat and power generation, electric power may sometimes be supplied using renewable energy power sources (solar power generation, wind power generation, etc.). 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 pipeline 88B. It should be noted that the first ammonia fuel gas supply pipeline 88B may also be configured to directly supply the ammonia gas as a gas turbine fuel gas to the burner 3. In any of the embodiments, the hydrogen contained in the ammonia gas combines with oxygen in the burner 3 to generate water. This water is recovered by the water recovery device 33 and then reused for the generation of ammonia gas. That is, in the combined heat and power system 10B, hydrogen is recycled.

[0089] According to the configuration in which the fuel gas generation device 80B includes the water decomposition device 61, ammonia gas derived from hydrogen can be supplied as the gas turbine fuel gas to the burner 3, and the cogeneration system 10B can reduce the amount of carbon dioxide emissions. In addition, the water generated by the combustion of ammonia gas derived from hydrogen in the burner 3 is recovered by the water recovery device 33, so 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 can be circulated within the cogeneration system 10B. Furthermore, according to the configuration in which the fuel gas generation device 80B includes the nitrogen extraction device 66 and the first ammonia generation device 71, by generating ammonia from hydrogen, the supply system of the gas turbine fuel gas can be further simplified. Specifically, the boiling point of ammonia is higher than that of other liquid fuels such as hydrogen, so the equipment for storing ammonia in a liquid phase can be simplified. A storage tank as such a storage device can be arranged in the first ammonia fuel gas supply pipeline 88B. Alternatively, a large vehicle or an oil tanker that stores and transports the ammonia generated by the first ammonia generation device 71 in a liquid phase can also be used.

[0090] Furthermore, according to the configuration in which the fuel gas generation device 80B includes the first ammonia fuel gas supply pipeline 88B, ammonia gas without carbon can be used as the gas turbine fuel gas, so the cogeneration system 10B can reduce the amount of carbon dioxide emissions.

[0091] It should be noted that although it is not an essential component of the second embodiment, the fuel gas generation unit 81B may also include the oxygen supply pipeline 64 described in the first embodiment. The advantages obtained by setting the oxygen supply pipeline 64 are as described in the first embodiment.

[0092] <4-3. Fuel Gas Generation Device 80C (80) of the Third Embodiment>

[0093] Refer to Figure 5C , an example shows the configuration of the fuel gas generation device 80C (80). In Figure 5C , the same reference numerals are assigned to the components that are the same as the components described with reference to Figure 5B , and the description of these components may be omitted hereinafter.

[0094] The fuel gas generation unit 81C (81) of the fuel gas generation device 80C includes a water decomposition device 61, a nitrogen extraction device 66, a nitrogen supply pipe 174, and a first ammonia generation device 71. The details of these components are as described in the second embodiment.

[0095] The fuel gas generation unit 81C includes an ammonia discharge pipeline 175, a first hydrogen generation device 51, and a first hydrogen fuel gas supply pipeline 88C instead of the first ammonia fuel gas supply pipeline 88B. The ammonia discharge pipeline 175 is connected to the first hydrogen generation device 51 and the gas mixing device 8. The first hydrogen fuel gas supply pipeline 88C is connected to the first hydrogen generation device 51 and the gas mixing device 8. The first hydrogen fuel gas supply pipeline 88C is an example of the fuel gas supply pipeline 88 (refer to Figure 1 ).

[0096] The first hydrogen generation device 51 is connected to the steam demand body 11 via a boiler steam supply pipeline 102. That is, the boiler steam discharged from the steam demand body 11 flows into the first hydrogen generation device 51. The first hydrogen generation device 51 is configured to generate hydrogen from ammonia discharged from the first ammonia generation device 71 using the boiler steam discharged from the heat recovery boiler 14 as a heat source. The first hydrogen generation device 51 in this example is configured to generate hydrogen by the thermal decomposition of ammonia using a catalytic decomposition reaction (cracking reaction) using a catalyst. In this thermal decomposition, the boiler steam is used as a heat source. In addition, the catalyst used in the cracking reaction is a Ru-based catalyst.

[0097] Figure 5C The first hydrogen fuel gas supply pipeline 88C exemplified in

[0098] is configured to supply the hydrogen generated by the first hydrogen generation device 51 to the gas mixing device 8 as a gas turbine fuel gas. The first hydrogen fuel gas supply pipeline 88C in other examples may also directly supply hydrogen as a gas turbine fuel gas to the burner 3. In any of the embodiments, the hydrogen that constitutes hydrogen combines with oxygen in the burner 3 to generate moisture. This moisture is recovered by the water recovery device 33 and is reused for the generation of ammonia (that is, the generation of hydrogen). That is, in the cogeneration system 10C, hydrogen circulates.

[0099] It should be noted that the combined heat and power system 10C is the same as the combined heat and power system 10B, including a nitrogen extraction device 66, a first ammonia production device 71, and an oxygen supply pipeline 64. The advantages obtained by having these components are as described in the second embodiment, and detailed descriptions are omitted to avoid repetition.

[0100] <4-4. Fuel Gas Generation Equipment 80D (80) of the Fourth Embodiment>

[0101] Refer to Figure 5D , and an example of the configuration of the fuel gas generation equipment 80D (80) is shown. In Figure 5D , the same reference numerals are assigned to the components that are the same as those described with reference to Figure 5B , and the descriptions of these components are sometimes omitted hereinafter.

[0102] The fuel gas generation unit 81D (81) of the fuel gas generation equipment 80D includes a nitrogen extraction device 66 and a nitrogen supply pipe 174. These components are as described in the second embodiment.

[0103] The fuel gas generation unit 81D further includes: a second ammonia production device 72, connected to the extraction pipeline 49 and the nitrogen supply pipe 174; and a second ammonia fuel gas supply pipeline 88D, connected to the second ammonia production device 72 and the gas mixing device 8. The second ammonia fuel gas supply pipeline 88D is an example of the fuel gas supply pipeline 88 (refer to Figure 1 ).

[0104] The second ammonia production device 72 is configured to generate ammonia from industrial water supplied through the extraction pipeline 49 and nitrogen supplied through the nitrogen supply pipe 174 by electrolytic synthesis. In the electrolytic synthesis of this example, a solid electrolyte that separates the two is used when applying a voltage to water and nitrogen. The hydrogen ions generated by applying a voltage to water move through the solid electrolyte to the nitrogen side. As a result, hydrogen and nitrogen combine to form ammonia. The ammonia generated during production is in a gaseous state. It should be noted that the electric power required for electrolytic synthesis is supplied by the electric power generated by the generator 5 (refer to Figure 2 ). In addition to the said power source, renewable energy power sources (solar power generation, wind power generation, etc.) are sometimes used to supply electric power.

[0105] The second ammonia fuel gas supply line 88D is configured to supply ammonia gas discharged from the second ammonia generation device 72 to the gas mixing device 8 as a gas turbine fuel gas. In other examples, the second ammonia fuel gas supply line 88D may also directly supply ammonia gas, which is a gas turbine fuel gas, to the burner 3. In any of the embodiments, the hydrogen contained in the ammonia gas combines with oxygen in the burner 3 to generate moisture. After the moisture is recovered by the water recovery device 33, it is reused for ammonia generation. That is to say, in the combined heat and power system 10D, hydrogen circulates.

[0106] According to the above configuration, ammonia is generated by electrolytic synthesis, so compared with the case of using the Haber - Bosch process, the number of processes required for generation can be reduced. Therefore, the second ammonia generation device 72 can generate ammonia with a simple process. In addition, by using ammonia as a gas turbine fuel gas, the gas turbine fuel gas supply system can be further simplified (details are as described in the second embodiment). In addition, since ammonia gas without carbon is used as the gas turbine fuel gas, the combined heat and power system 10D can reduce the carbon dioxide emission.

[0107] In some embodiments, the fuel gas generation device 80D (80) may further include: an oxygen supply line 65 for supplying oxygen generated during the generation of ammonia in the second ammonia generation device 72 to the burner 3. The oxygen flowing through the oxygen supply line 65 is mixed with the compressed air 7 in the burner housing 23 (refer to Figure 3 ), and then flows into the burner liner 26 (refer to Figure 3 ). According to the above configuration, by using the oxygen generated in the second ammonia generation device 72 as an oxidant for the burner 3, the industrial water that is the object of water decomposition treatment can be effectively utilized without waste.

[0108] <4 - 5. The fuel gas generation device 80E (80) of the fifth embodiment>

[0109] Refer to Figure 5E , and the configuration of the fuel gas generation device 80E (80) is illustrated by way of example. In Figure 5E , the same reference numerals are assigned to the components that are the same as those described with reference to Figure 5D , and the description of these components will sometimes be omitted hereinafter.

[0110] The fuel gas generation unit 81E (81) of the fuel gas generation device 80E includes a nitrogen extraction device 66, a nitrogen supply pipe 174, and a second ammonia generation device 72. These components are as described in the fourth embodiment. In addition, the fuel gas generation device 80E (80) further includes an oxygen supply line 65. This component is also as described in the fourth embodiment.

[0111] The fuel gas generation unit 81E includes an ammonia discharge pipeline 176, a second hydrogen generation device 52, and a second hydrogen fuel gas supply pipeline 88E (88). The ammonia discharge pipeline 176 is connected to the second ammonia generation device 72 and the second hydrogen generation device 52. The ammonia discharge pipeline 176 supplies the ammonia discharged from the second ammonia generation device 72 to the second hydrogen generation device 52. The second hydrogen fuel gas supply pipeline 88E (88) is connected to the second hydrogen generation device 52 and the gas mixing device 8. The second hydrogen fuel gas supply pipeline 88E is an example of the fuel gas supply pipeline 88 (refer to Figure 1 ).

[0112] The second hydrogen generation device 52 has the same configuration as the first hydrogen generation device 51. The second hydrogen generation device 52 is connected to the steam demand body 11 via a boiler steam supply pipeline 102. And, the second hydrogen generation device 52 is configured to generate hydrogen from the ammonia discharged from the second ammonia generation device 72 using the boiler steam discharged from the heat recovery boiler 14 as a heat source. The method of generating hydrogen is the same as that of the first hydrogen generation device 51 (refer to Figure 5C ), so the detailed description is omitted.

[0113] The second hydrogen fuel gas supply pipeline 88E supplies the hydrogen generated by the second hydrogen generation device 52 as a gas turbine fuel gas to the gas mixing device 8. It should be noted that the second hydrogen fuel gas supply pipeline 88E may also be configured to directly supply the hydrogen as a gas turbine fuel gas to the burner 3. In any of the embodiments, the hydrogen that constitutes the hydrogen combines with oxygen in the burner 3 to generate moisture. This moisture is recovered by the water recovery device 33 and then reused for ammonia generation (that is, hydrogen generation). That is, in the cogeneration system 10E, hydrogen circulates.

[0114] According to the above configuration, hydrogen with a relatively high calorific value per unit weight can be used as a gas turbine fuel gas, so the supply amount of other fuel gases outside the cogeneration system 10E can be reduced. In addition, the advantages obtained by the fuel gas generation device 80E having the second ammonia generation device 72 are as described in the fourth embodiment, so the detailed description is omitted. The advantages of the fuel gas generation device 80E having the oxygen supply pipeline 65 are also as described in the fourth embodiment, so the detailed description is omitted.

[0115] <4-6. The fuel gas generation device 80F (80) of the sixth embodiment>

[0116] Refer to Figure 5F, an example of the configuration of the fuel gas generation device 80F (80) is shown. The fuel gas generation unit 81F (81) of the fuel gas generation device 80F includes the above-described water decomposition device 61. Moreover, the fuel gas generation unit 81F includes a hydrogen fuel gas supply pipeline 88F (88) connected to the water decomposition device 61 and the gas mixing device 8. The hydrogen fuel gas supply pipeline 88F is configured to supply the hydrogen gas generated by the water decomposition device 61 to the gas mixing device 8 as a gas turbine fuel gas. The hydrogen fuel gas supply pipeline 88F is an example of the fuel gas supply pipeline 88 (refer to Figure 1 ). It should be noted that the hydrogen fuel gas supply pipeline 88F may also directly supply hydrogen gas to the burner 3. In any of the embodiments, the hydrogen that constitutes hydrogen gas combines with oxygen in the burner 3 to generate water. After the water is recovered by the water recovery device 33, it is reused for the generation of hydrogen gas. That is to say, in the cogeneration system 10F, hydrogen circulates.

[0117] According to the above configuration, 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 such as fossil fuel gas outside the cogeneration system 10F can be reduced.

[0118] <4-7. Others>

[0119] The fuel gas generation devices 80A to 80F (80) of the first to sixth embodiments can be provided separately, or any at least two or more of the fuel gas generation devices 80A to 80F can be combined. In addition, in the fuel gas generation devices 80B and 80D that use ammonia as the gas turbine fuel gas, it is preferable to provide the above-described upstream steam pipe 131 (refer to Figure 2 , Figure 3 ). When the large gas turbine 9 operates effectively, the temperature of the combustion chamber formed inside the burner liner 26 is high, and nitrogen oxides are likely to be generated during the combustion of ammonia. In this regard, by supplying boiler steam to the head end 24 side of the burner 3 through the upstream steam pipe 131, the advantage of significantly suppressing the generation amount of nitrogen oxides can be obtained.

[0120] <5. Method for retrofitting the cogeneration system 10G>

[0121] Refer to Figure 1 , Figure 6 , Figure 7 , a method for retrofitting the cogeneration system 10G, which is the cogeneration system 10 before retrofitting, into the cogeneration system 10 will be described. Figure 6 is a schematic diagram of the cogeneration system 10G according to an embodiment of the present disclosure. Figure 7 is a flowchart showing the method for retrofitting the cogeneration system 10G.

[0122] Before describing the modification method, the combined heat and power supply system 10G (10) will be described first. The combined heat and power supply system 10G does not have Figure 1 the additional unit 4 shown (that is, the water recovery system 40 and the fuel gas generation device 80). In addition, an exhaust air damper 31 is not provided in the exhaust pipe line 29 of the combined heat and power supply system 10G (refer to Figure 1 ). The combined heat and power supply system 10 is achieved by adding the additional unit 4 and the exhaust air damper 31 to the combined heat and power supply system 10G. The detailed modification method is as described below.

[0123] First, perform the water recovery system addition step (S11) of adding the water recovery system 40 including the water recovery device 33. Specifically (also refer to Figure 4 ), set up the water recovery system 40, and connect the inlet of the waste gas supply pipeline 141 to the connection part of the waste gas pipeline 57 and the exhaust pipe line 29. In addition, connect the water supply pipeline 43 to the makeup water tank 17. That is, connect the outlets of the high-temperature water supply pipeline 44 and the low-temperature water supply pipeline 47 to the makeup water tank 17.

[0124] Next, perform the exhaust air damper addition step (S13) of adding the exhaust air damper 31 to the exhaust pipe line 29. It should be noted that if the exhaust air damper 31 is provided in the exhaust pipe line 29 before the modification, S13 can be omitted.

[0125] Next, perform the fuel gas generation device addition step (S15) of adding the fuel gas generation device 80. Specifically, connect the inlet of the extraction pipeline 49 to the water supply pipeline 19, and connect the outlet of the mixed fuel gas supply pipeline 86 (refer to Figure 1 ) to the mixed fuel gas supply device 79. Thus, the combined heat and power supply system 10 is completed.

[0126] It should be noted that when adding the fuel gas generation device 80A (refer to Figure 5A ), the following steps are additionally performed in S15: Connect the waste gas flow outlet of the water recovery device 33 and the carbon dioxide recovery device 62 using the waste gas supply pipeline 109.

[0127] In addition, when adding the fuel gas generation device 80C (refer to Figure 5C ), the following steps are additionally performed in S15: Connect the first hydrogen generation device 51 and the steam demand body 11 using the boiler steam supply pipeline 102.

[0128] Similarly, when adding the fuel gas generation device 80E (refer to Figure 5E ), the following steps are additionally performed in S15: Connect the second hydrogen generation device 52 and the steam demand body 11 using the boiler steam supply pipeline 102.

[0129] Moreover, when fuel gas generation devices 80A, 80B, 80C, 80F ( Figure 5A , Figure 5B , Figure 5C , Figure 5F ) including a water decomposition device 61 are additionally provided, the following steps can also be additionally executed in S15: Connect the water decomposition device 61 and the burner 3 through an oxygen supply pipeline 64.

[0130] The retrofit method of the cogeneration system 10G described above is executed by an operator, a robotic arm operated by the operator, or a combination thereof.

[0131] <6. Summary>

[0132] The content described in some of the above embodiments is grasped as follows, for example.

[0133] 1) The gas turbine cogeneration system (10) of at least one embodiment of the present disclosure includes:

[0134] A gas turbine (9) including a burner (3);

[0135] An exhaust heat recovery boiler (14) for generating boiler steam using the exhaust gas (13) discharged from the gas turbine as a heat source;

[0136] A water recovery device (33) for recovering moisture from the exhaust gas through heat exchange between the exhaust gas discharged from the exhaust heat recovery boiler and refrigerant water; and

[0137] A fuel gas generation device (80) for generating gas turbine fuel gas to be supplied to the burner using at least one of industrial water containing the recovered water recovered by the water recovery device as a raw material substance.

[0138] 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 effectively used as at least one of the raw material substances of the gas turbine fuel gas. The supply amount of other fuel gases such as fossil fuel gas can be reduced according to the amount of gas turbine fuel gas supplied to the burner. Therefore, the gas turbine cogeneration system can reduce the carbon dioxide emission amount. In addition, the moisture contained in the exhaust gas is recovered by the water recovery device and then used as gas turbine fuel gas, and the moisture generated by the combustion of the gas turbine fuel gas will be recovered by the water recovery device again. In this way, a gas turbine cogeneration system in which the substances constituting the moisture are recycled is realized, the supply amount of fossil fuel gas outside the system of this system can be reduced, and it can contribute to carbon neutrality.

[0139] 2) In some embodiments, according to the gas turbine cogeneration system as described in 1) above, wherein,

[0140] The fuel gas generation device further includes: a water decomposition device (61) for performing water decomposition treatment on the industrial water to generate hydrogen gas.

[0141] According to the configuration of the above 2), it is possible to generate a gas turbine fuel gas that is hydrogen or a gas turbine fuel gas derived from hydrogen, and reduce the carbon dioxide emission. In addition, the moisture generated by the combustion of the gas turbine fuel gas that is hydrogen or the gas turbine fuel gas derived from hydrogen in the burner is recovered by the water recovery device. Therefore, 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 outside the system can be reduced. In addition, hydrogen can be circulated within the cogeneration system.

[0142] 3) In some embodiments, for the gas turbine cogeneration system described in the above 2), wherein,

[0143] The fuel gas generation device further includes:

[0144] A carbon dioxide recovery device (62) for recovering carbon dioxide from the exhaust gas using the boiler steam discharged from the exhaust heat recovery boiler, the exhaust gas being discharged from the water recovery device;

[0145] A methane generation device (63) for generating methane gas from the hydrogen generated by the water decomposition device and the carbon dioxide recovered by the carbon dioxide recovery device; and

[0146] A methane fuel gas supply pipeline (88A) for supplying the methane gas as the gas turbine fuel gas to the burner.

[0147] According to the configuration of the above 3), it is possible to supply methane gas derived from hydrogen as the gas turbine fuel gas to the burner. In addition, carbon dioxide contained in the exhaust gas is utilized in the generation of methane gas, so the carbon dioxide emission can be reduced. Moreover, the heat of the boiler steam is utilized in the generation of carbon dioxide, so energy conservation can be achieved.

[0148] 4) In some embodiments, for the gas turbine cogeneration system described in the above 2) or 3), wherein,

[0149] The fuel gas generation device further includes: a hydrogen fuel gas supply pipeline (88F) for supplying the hydrogen generated by the water decomposition device as the gas turbine fuel gas to the burner.

[0150] According to the configuration of the above 4), hydrogen with a higher 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.

[0151] 5) In some embodiments, for the gas turbine combined heat and power generation system according to any one of 2) to 4) above, wherein,

[0152] The fuel gas generation device further includes:

[0153] A nitrogen extraction device (66) for extracting nitrogen from the atmosphere; and

[0154] A first ammonia generation device (71) for generating ammonia from the hydrogen generated by the water decomposition device and the nitrogen extracted by the nitrogen extraction device.

[0155] According to the configuration of 5) above, by generating ammonia from hydrogen, the supply system of the gas turbine fuel gas can be further simplified. More specifically, the boiling point of ammonia is higher than that of other liquid fuels such as hydrogen, so the equipment for storing the fuel of the gas turbine in a liquid phase can be simplified.

[0156] 6) In some embodiments, for the gas turbine combined heat and power generation system according to 5) above, wherein,

[0157] The fuel gas generation device further includes: a first ammonia fuel gas supply pipeline (88B) for supplying the ammonia gas discharged from the first ammonia generation device to the burner as the gas turbine fuel gas.

[0158] According to the configuration of 6) above, ammonia gas without carbon is used as the gas turbine fuel gas, so the carbon dioxide emission can be reduced.

[0159] 7) In some embodiments, for the gas turbine combined heat and power generation system according to 5) above, wherein,

[0160] The fuel gas generation device further includes:

[0161] A first hydrogen generation device (51) for generating hydrogen from the ammonia gas discharged from the first ammonia generation device using the boiler steam discharged from the heat recovery boiler as a heat source; and

[0162] A first hydrogen fuel gas supply pipeline (88C) for supplying the hydrogen generated by the first hydrogen generation device to the burner as the gas turbine fuel gas.

[0163] According to the configuration of 7) above, hydrogen with a higher 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 combined heat and power generation system can be reduced.

[0164] 8) In some embodiments, for the gas turbine combined heat and power generation system according to any one of 2) to 7) above, wherein,

[0165] The gas turbine combined heat and power generation system further includes: an oxygen supply pipeline (64) for supplying oxygen generated during the generation of the hydrogen in the water decomposition device to the burner.

[0166] According to the configuration of 8) above, by using the oxygen generated in the water decomposition device as the oxidant of the burner, the industrial water to be subjected to the water decomposition treatment can be effectively utilized without waste.

[0167] 9) In some embodiments, for the gas turbine combined heat and power generation system according to 1) above, wherein,

[0168] The fuel gas generation device further includes:

[0169] A nitrogen extraction device (66) for extracting nitrogen from the atmosphere; and

[0170] A second ammonia generation device (72) for generating ammonia by electrolytic synthesis from the industrial water and the nitrogen extracted by the nitrogen extraction device.

[0171] According to the configuration of 9) above, ammonia is generated by electrolytic synthesis, so the second ammonia generation device can generate ammonia with a simple process. By using ammonia as the fuel gas of the gas turbine, the fuel gas supply system of the gas turbine can be further simplified. More specifically, the boiling point of ammonia is higher than that of other liquid fuels such as hydrogen, so the equipment for storing the fuel of the gas turbine in a liquid phase can be simplified.

[0172] 10) In some embodiments, the gas turbine combined heat and power generation system according to 9) above further includes:

[0173] An oxygen supply pipeline (65) for supplying oxygen generated during the generation of the ammonia in the second ammonia generation device to the burner.

[0174] According to the configuration of 10) above, by using the oxygen generated in the second ammonia generation device as the oxidant of the burner, the industrial water to be subjected to the water decomposition treatment can be effectively utilized without waste.

[0175] 11) In some embodiments, for the gas turbine combined heat and power generation system according to 9) or 10) above, wherein,

[0176] The fuel gas generation device further includes: a second ammonia fuel gas supply pipeline (88D) for supplying the ammonia discharged from the second ammonia generation device as the fuel gas of the gas turbine to the burner.

[0177] According to the configuration of the above item 11), the same effect as that of the above item 6) can be obtained.

[0178] 12) In some embodiments, for the gas turbine combined heat and power generation system according to any one of the above items 9) to 11), wherein,

[0179] The fuel gas generation device further includes:

[0180] A second hydrogen generation device (52) for generating hydrogen from ammonia discharged from the second ammonia generation device using the boiler steam discharged from the waste heat recovery boiler as a heat source; and

[0181] A second hydrogen fuel gas supply pipeline (88E) for supplying the hydrogen generated by the second hydrogen generation device to the burner as the gas turbine fuel gas.

[0182] According to the configuration of the above item 12), the same effect as that of the above item 7) can be obtained.

[0183] 13) In some embodiments, for the gas turbine combined heat and power generation system according to any one of the above items 1) to 12), wherein,

[0184] The fuel gas generation device includes:

[0185] A gas mixing device (8) for mixing the gas turbine fuel gas and the fossil fuel gas to generate a mixed fuel gas; and

[0186] A mixed fuel gas supply pipeline (86) for supplying the mixed fuel gas to the burner.

[0187] According to the configuration of the above item 13), since the mixed fuel gas supplied to the burner contains the fossil fuel gas, the calorific value generated by the combustion of the burner can be sufficiently ensured.

[0188] 14) In some embodiments, the gas turbine combined heat and power generation system according to any one of the above items 1) to 13) further includes:

[0189] 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 burner.

[0190] According to the configuration of the above item 14), by injecting the boiler steam into the burner, the generation of nitrogen oxides in the burner can be suppressed. In addition, after the injected boiler steam is mixed into the exhaust gas, it will be recovered by the water recovery device as the moisture contained in the exhaust gas. Thus, a sufficient amount of recovered water can be recovered, and therefore the fuel gas generation device can generate a sufficient amount of gas turbine fuel gas.

[0191] 15) The retrofit method of the gas turbine combined heat and power generation system (10) according to at least one embodiment of the present disclosure is a retrofit method of the gas turbine combined heat and power generation system (10) including a gas turbine (9) having a burner (3) and a heat recovery boiler (14), and the retrofit method of the combined heat and power generation system (10) includes the following steps:

[0192] A water recovery device addition step (S11) for adding a water recovery device (33) that recovers moisture from the exhaust gas (13) by heat exchange between the exhaust gas discharged from the heat recovery boiler and refrigerant water; and

[0193] A fuel gas generation device addition step (S15) for adding a fuel gas generation device (80) that generates gas turbine fuel gas for supply to the burner using at least one of industrial water containing the recovered water recovered by the water recovery device as a raw material substance.

[0194] According to the configuration of the above 15), the same effects as those of the above 1) can be obtained.

[0195] 16) The addition unit (4) for a gas turbine combined heat and power generation system according to at least one embodiment of the present disclosure includes:

[0196] A water recovery device (33) that recovers moisture from the exhaust gas (13) by heat exchange between the exhaust gas discharged from the heat recovery boiler (14) and refrigerant water; and

[0197] A fuel gas generation device (80) that generates gas turbine fuel gas for supply to the burner (3) of the gas turbine (9) using at least one of industrial water containing the recovered water recovered by the water recovery device as a raw material substance.

[0198] According to the configuration of the above 16), the same effects as those of the above 1) can be obtained.

[0199] Explanation of reference numerals

[0200] 1: Combined heat and power generation system;

[0201] 2: Turbine;

[0202] 3: Burner;

[0203] 4: Addition unit for gas turbine combined heat and power generation system;

[0204] 4: Addition unit;

[0205] 5: Generator;

[0206] 6: Compressor inlet air;

[0207] 7: Compressed air;

[0208] 8: Gas mixing device;

[0209] 9: Gas turbine;

[0210] 10: Gas turbine combined heat and power system (combined heat and power system);

[0211] 11: Steam demand body;

[0212] 12: Combustion gas;

[0213] 13: Exhaust gas;

[0214] 14: Exhaust heat recovery boiler;

[0215] 21: Steam supply pipe;

[0216] 24: Head end;

[0217] 25: Fuel nozzle;

[0218] 26: Burner liner;

[0219] 27: Burner tail pipe;

[0220] 28: Flame;

[0221] 29: Exhaust pipeline;

[0222] 30: Exhaust tower;

[0223] 31: Exhaust damper;

[0224] 33: Water recovery device;

[0225] 49: Extraction pipeline;

[0226] 51: First hydrogen generation device;

[0227] 52: Second hydrogen generation device;

[0228] 55: Cooling water supply pump;

[0229] 57: Exhaust gas pipeline;

[0230] 59: Water recovery damper;

[0231] 61: Water decomposition device;

[0232] 62: Carbon dioxide recovery device;

[0233] 63: Methane generation device;

[0234] 64, 65: Oxygen supply pipeline;

[0235] 66: Nitrogen extraction device;

[0236] 71: First ammonia generation device;

[0237] 72: Second ammonia generation device;

[0238] 80: Fuel gas generation equipment;

[0239] 81: Fuel gas generation section;

[0240] 86: Mixed fuel gas supply pipeline;

[0241] 88: Fuel gas supply pipeline;

[0242] 88A: Methane fuel gas supply pipeline;

[0243] 88B: First ammonia fuel gas supply pipeline;

[0244] 88C: First hydrogen fuel gas supply pipeline;

[0245] 88D: Second ammonia fuel gas supply pipeline;

[0246] 88E: Second hydrogen fuel gas supply pipeline;

[0247] 88F: Hydrogen fuel gas supply pipeline;

[0248] 91: Hydrogen supply pipeline;

[0249] 101: Boiler steam supply pipeline;

[0250] 102: Boiler steam supply pipeline;

[0251] 109: Exhaust gas supply pipeline;

[0252] 130: Steam extraction pipe;

[0253] 131: Upstream side steam pipe;

[0254] 131A: Upstream side steam flow control valve;

[0255] 132: Downstream side steam pipe;

[0256] 132A: Downstream side steam flow control valve;

[0257] 135: Heat exchange container;

[0258] 162: Carbon dioxide supply pipeline;

[0259] 173: Hydrogen supply pipe;

[0260] 174: Nitrogen supply pipe;

[0261] 175, 176: Ammonia discharge pipelines.

Claims

1. A gas turbine combined heat and power supply system, the gas turbine combined heat and power supply system comprising: A gas turbine including a burner; 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 through heat exchange between the exhaust gas discharged from the exhaust heat recovery boiler and refrigerant water; and A fuel gas generation device for generating gas turbine fuel gas for supply to the burner using at least one of industrial water containing the recovered water recovered by the water recovery device as a raw material substance.

2. The gas turbine combined heat and power supply system according to claim 1, wherein, The fuel gas generation device further includes: a water decomposition device for performing water decomposition treatment on the industrial water to generate hydrogen gas.

3. The gas turbine combined heat and power supply system according to claim 2, wherein, The fuel gas generation device further includes: a carbon dioxide recovery device for recovering carbon dioxide from the waste gas discharged from the water recovery device using the boiler steam discharged from the exhaust 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; and a methane fuel gas supply pipeline for supplying the methane gas as the gas turbine fuel gas to the burner.

4. The gas turbine combined heat and power supply system according to claim 2 or 3, wherein, The fuel gas generation device further includes: a hydrogen fuel gas supply pipeline for supplying the hydrogen gas generated by the water decomposition device as the gas turbine fuel gas to the burner.

5. The gas turbine combined heat and power supply system according to claim 2 or 3, wherein, The fuel gas generation device further includes: a nitrogen extraction device for extracting nitrogen from the atmosphere; and a first ammonia generation device for generating ammonia from the hydrogen gas generated by the water decomposition device and the nitrogen extracted by the nitrogen extraction device.

6. The gas turbine combined heat and power supply system according to claim 5, wherein, The fuel gas generation device further includes: a first ammonia fuel gas supply pipeline for supplying the ammonia gas discharged from the first ammonia generation device as the gas turbine fuel gas to the burner.

7. The gas turbine combined heat and power supply system according to claim 5, wherein, The fuel gas generation device further includes: a first hydrogen generation device for generating hydrogen gas from the ammonia gas discharged from the first ammonia generation device using the boiler steam discharged from the exhaust heat recovery boiler as a heat source; and a first hydrogen fuel gas supply pipeline for supplying the hydrogen gas generated by the first hydrogen generation device as the gas turbine fuel gas to the burner.

8. The gas turbine combined heat and power supply system according to claim 2 or 3, wherein, The gas turbine combined heat and power system further includes: an oxygen supply pipeline for supplying the oxygen generated during the generation of the hydrogen gas in the water decomposition device to the burner.

9. The gas turbine combined heat and power supply system according to claim 1, wherein, The fuel gas generation device further includes: a nitrogen extraction device for extracting nitrogen from the atmosphere; and a second ammonia generation device for generating ammonia by electrolytic synthesis from the industrial water and the nitrogen extracted by the nitrogen extraction device.

10. The gas turbine combined heat and power supply system according to claim 9, wherein, The gas turbine combined heat and power system further includes: an oxygen supply pipeline for supplying the oxygen generated during the generation of the ammonia in the second ammonia generation device to the burner.

11. The gas turbine combined heat and power supply system according to claim 9 or 10, wherein, The fuel gas generation device further includes: a second ammonia fuel gas supply pipeline for supplying the ammonia gas discharged from the second ammonia generation device as the gas turbine fuel gas to the burner.

12. The gas turbine combined heat and power supply system according to claim 9 or 10, wherein, The fuel gas generation device further includes: a second hydrogen generation device for generating hydrogen gas from the ammonia gas discharged from the second ammonia generation device using the boiler steam discharged from the exhaust heat recovery boiler as a heat source; and a second hydrogen fuel gas supply pipeline for supplying the hydrogen gas generated by the second hydrogen generation device as the gas turbine fuel gas to the burner.

13. The gas turbine combined heat and power supply system according to any one of claims 1 to 3, wherein, The fuel gas generation device includes: 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 pipeline for supplying the mixed fuel gas to the burner.

14. The gas turbine combined heat and power supply system according to any one of claims 1 to 3, wherein, The gas turbine combined heat and power generation system further includes a head-end side steam supply pipe for supplying the boiler steam discharged from the heat recovery boiler to the head-end side of the burner.

15. A method for retrofitting a gas turbine combined heat and power supply system, the gas turbine combined heat and power supply system comprising a gas turbine including a burner and a heat recovery boiler, the method for retrofitting the gas turbine combined heat and power supply system comprising the following steps: A step of adding a water recovery device for 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 refrigerant water; and A step of adding a fuel gas generation device for adding a fuel gas generation device for generating a gas turbine fuel gas for supplying to the burner by using at least one of industrial water containing the recovered water recovered by the water recovery device as a raw material substance.

16. An additional unit for a gas turbine combined heat and power supply system, the additional unit for a gas turbine combined heat and power supply system comprising: 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 refrigerant water; and A fuel gas generation device for generating a gas turbine fuel gas for supplying to the burner of the gas turbine by using at least one of industrial water containing the recovered water recovered by the water recovery device as a raw material substance.

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