Simultaneous firing of a combustor using gaseous fuel and liquid ammonia.

Abstract

This invention provides a method for simultaneously firing combustors using gaseous fuel and liquid ammonia, employing various techniques. [Solution] Each method fires gaseous fuel in a primary combustion zone (188) using a head-end fuel nozzle set (182), a secondary combustion zone (194) using a first axial fuel stage (AFS) injector set (180), and / or a tertiary combustion zone (204) using a second AFS injector set (200) over a specific combustor load range, and then transitions to firing with ammonia using an ammonia sprayer (210). The method can transition to ammonia combustion alone or to ammonia combustion with gaseous fuel.

Description

Technical Field

[0001] The present disclosure generally relates to a turbomachinery combustor, and more specifically to a method of co-firing a combustor using gaseous fuel and liquid ammonia.

Background Art

[0002] A gas turbine system includes a combustion section that includes a plurality of combustors that generate a flow of combustion gases in which fuel is burned and converted to kinetic energy in a downstream turbine section. Current combustors include a head-end fuel nozzle assembly that includes a plurality of nozzles for burning fuel in a (primary) combustion zone. A first axial fuel stage (AFS) injector can be used to burn fuel in a secondary combustion zone downstream of the primary combustion zone, and a second AFS injector can be used to burn fuel in a tertiary combustion zone downstream of the secondary combustion zone. For example, a portion of the air supply from the compressor outlet is delivered to the head-end fuel nozzle assembly and the AFS injectors in various flow paths.

[0003] One problem with conventional combustors is that the combustion of hydrocarbons (e.g., natural gas) generally results in the formation of carbon dioxide (CO2) and nitrogen oxides (NOx) that are costly to mitigate. To reduce the amount of CO2 generated, some manufacturers have attempted to use alternative fuel sources that include hydrogen and / or ammonia to remove carbon from the combustion products. However, current combustors present challenges with respect to using liquid ammonia as a fuel. In particular, ammonia has low flammability, low heat of combustion, and is not very stable, which can potentially extinguish at least a portion of the combustion reaction.

Summary of the Invention

[0004] All aspects, examples, and features described below can be combined in any technically possible way.

[0005] Simultaneous firing of a combustor using gaseous fuel and ammonia using various methods is disclosed. Each method fires (ignites) the gaseous fuel in a primary combustion zone using a head-end fuel nozzle, a secondary combustion zone using a first axial fuel stage (AFS) injector set, and / or a tertiary combustion zone using a second AFS injector set, over a specific combustor load range, and then transitions to firing with ammonia using an ammonia sprayer. The method can transition to ammonia combustion alone or ammonia combustion with gaseous fuel. Cross-flow of the first AFS injector set stabilizes the ammonia combustion, and the second AFS injector set provides a quench effect, each contributing to efficient ammonia combustion with or without gaseous fuel.

[0006] One aspect of the present disclosure relates to a combustor comprising: a head-end (HE) fuel nozzle set directed toward a combustion liner for burning fuel in a primary combustion zone; a first axial fuel stage (AFS) injector set directed toward a combustion liner for burning fuel in a secondary combustion zone downstream of the primary combustion zone; a second AFS injector set directed toward a combustion liner for burning fuel in a tertiary combustion zone downstream of the secondary combustion zone; and an ammonia sprayer directed toward a combustion liner for burning ammonia in at least the primary combustion zone, wherein the combustor comprises the steps of: supplying fuel to the HE fuel nozzle set and introducing gaseous fuel into the primary combustion zone for combustion in a first combustor load range from 0% to 50% combustor load; and supplying fuel to the first AFS injector set for a second combustor load range from 10-20% to 50% combustor load. The method includes the steps of supplying additional fuel to the combustor and introducing gaseous fuel into the secondary combustion zone for combustion; supplying additional fuel to the second AFS injector set for a third combustor load range between 35% and 50% combustor loads for gaseous fuel into the tertiary combustion zone for combustion; transitioning to an ammonia fuel supply mode at 50% combustor load by stopping the supply of gaseous fuel to the HE fuel nozzle set, the first AFS injector set, and the second AFS injector set, and initiating the combustion of ammonia in at least the primary combustion zone using an ammonia sprayer; and supplying fuel only to the ammonia sprayer for a fourth combustor load range between combustor loads above 50% and 100% combustor loads for ammonia to introduce and burn ammonia in at least the primary combustion zone.

[0007] Another aspect of the present disclosure includes any of the preceding aspects, which involves gradually increasing the fuel mass flow rate (FMFR) of ammonia to an ammonia sprayer, then gradually decreasing the FMFR of gaseous fuel to a HE fuel nozzle set to zero, then gradually decreasing the FMFR of gaseous fuel to a first AFS injector set to zero, and then gradually decreasing the FMFR of gaseous fuel to a second AFS injector set to zero.

[0008] Another aspect of the present disclosure includes, and transitions to, any of the preceding aspects, further including, temporarily maintaining the FMFR of ammonia to the ammonia sprayer at a first current level before initiating a gradual decrease of the FMFR of gas fuel to a first AFS injector set to zero, and continuing a gradual increase of the FMFR of ammonia to the ammonia sprayer after initiating a gradual decrease of the FMFR of gas fuel to a first AFS injector set to zero, and temporarily maintaining the FMFR of ammonia to the ammonia sprayer at a second current level before initiating a gradual decrease of the FMFR of gas fuel to a second AFS injector set to zero, and continuing a gradual increase of the FMFR of ammonia to the ammonia sprayer after initiating a gradual decrease of the FMFR of gas fuel to a second AFS injector set to zero.

[0009] Another aspect of the present disclosure includes any of the preceding aspects, and further includes setting the FMFR of ammonia to the ammonia sprayer to a maximum desired level in response to the FMFR of gaseous fuel to the second AFS injector reaching zero.

[0010] Another aspect of the present disclosure includes any of the aforementioned aspects and further comprises injecting only air using an HE fuel nozzle set, a first AFS injector set, and a second AFS injector set for a fourth combustor load range between a combustor load greater than 50% and a combustor load of 100%.

[0011] Another aspect of the present disclosure relates to a combustor comprising a head-end (HE) fuel nozzle set directed toward a combustion liner for burning fuel in a primary combustion zone, a first axial fuel stage (AFS) injector set directed toward a combustion liner for burning fuel in a secondary combustion zone downstream of the primary combustion zone, a second AFS injector set directed toward a combustion liner for burning fuel in a tertiary combustion zone downstream of the secondary combustion zone, and an ammonia sprayer directed toward the combustion liner for burning ammonia in at least the primary combustion zone, wherein during a first simultaneous firing mode, fuel is supplied to the HE fuel nozzle set for a first combustor load range from 0% combustor load to 50% combustor load, and The method includes the steps of: introducing gaseous fuel into the secondary combustion zone and burning it; supplying additional fuel to the first AFS injector set for a second combustor load range from 10-20% to 50% combustor load, introducing gaseous fuel into the secondary combustion zone and burning it; supplying additional fuel to the second AFS injector set for a third combustor load range between 35% and 50% combustor load, introducing gaseous fuel into the tertiary combustion zone and burning it; and supplying fuel to the ammonia sprayer for a fourth combustor load range between 20% and 100% combustor load, introducing ammonia into at least the primary combustion zone and burning it.

[0012] Another aspect of the present disclosure includes any of the preceding aspects, further comprising transitioning to ammonia fuel operation by stopping the fuel supply from the HE fuel nozzle set, the first AFS injector set and the second AFS injector set at a 50% combustor load, and injecting only air using the HE fuel nozzle set, the first AFS injector set and the second AFS injector set between a 50% combustor load and a 100% combustor load.

[0013] Another aspect of the present disclosure includes any of the preceding aspects, wherein during a second simultaneous firing mode, the method includes supplying fuel to a second AFS injector set and introducing and burning gaseous fuel in a tertiary combustion zone in a combustor load range between 50% and 100% combustor load.

[0014] Another aspect of this disclosure includes any of the aforementioned aspects, wherein the gas fuel fraction of the total fuel amount is less than 20% between a 50% combustor load and a 100% combustor load.

[0015] Another aspect of the present disclosure includes any of the aforementioned aspects and further includes injecting only air using an HE fuel nozzle set and a first AFS injector set between a 50% combustor load and a 100% combustor load.

[0016] Another aspect of the present disclosure includes any of the preceding aspects, wherein in a third simultaneous firing mode, the method includes supplying fuel to an HE fuel nozzle set to introduce and burn gaseous fuel in a primary combustion zone in a combustor load range from 50% to 100% combustor load, and supplying fuel to a second AFS injector set to introduce and burn gaseous fuel in a tertiary combustion zone in a combustor load range between 50% and 100% combustor load.

[0017] Another aspect of this disclosure includes any of the aforementioned aspects, wherein the gas fuel fraction of the total fuel amount is between 20% and 50% between a 50% combustor load and a 100% combustor load.

[0018] Another aspect of the present disclosure includes any of the aforementioned aspects, further comprising injecting only air using a first AFS injector set between a 50% combustor load and a 100% combustor load.

[0019] Another aspect of the present disclosure includes any of the preceding aspects, wherein in a fourth simultaneous firing mode, the method includes supplying fuel to an HE fuel nozzle set to introduce and burn gaseous fuel in a primary combustion zone between a 50% combustor load and a 100% combustor load; supplying fuel to a first AFS injector set to introduce and burn gaseous fuel in a secondary combustion zone between a 50% combustor load and a 100% combustor load; and supplying fuel to a second AFS injector set to introduce and burn gaseous fuel in a tertiary combustion zone between a 50% combustor load and a 100% combustor load.

[0020] Another aspect of this disclosure includes any of the preceding aspects, wherein the gas fuel fraction of the total fuel is greater than 50% between a 50% combustor load and a 100% combustor load.

[0021] Another aspect of the present disclosure includes a combustor for turbomachinery, comprising: a head-end (HE) fuel nozzle set directed toward a combustion liner for burning fuel in a primary combustion zone; a first axial fuel stage (AFS) injector set directed toward a combustion liner for burning fuel in a secondary combustion zone downstream of the primary combustion zone; a second AFS injector set directed toward a combustion liner for burning fuel in a tertiary combustion zone downstream of the secondary combustion zone; an ammonia sprayer directed toward a combustion liner for burning ammonia in at least the primary combustion zone; and a controller configured to sequentially supply gaseous fuel to the HE fuel nozzle set, the first AFS injector set, and the second AFS injector set, and to supply ammonia as ammonia fuel to the ammonia sprayer from 20% combustor load to 100% combustor load.

[0022] Another aspect of the present disclosure includes any of the preceding aspects, wherein the controller operates the combustor in a first simultaneous firing operating mode, which includes the steps of: supplying fuel to an HE fuel nozzle set and introducing and burning gaseous fuel in a primary combustion zone for a first combustor load range from 0% combustor load to 50% combustor load; supplying fuel to a first AFS injector set and introducing and burning gaseous fuel in a secondary combustion zone for a second combustor load range from 10-20% combustor load to 50% combustor load; supplying fuel to a second AFS injector set and introducing and burning gaseous fuel in a tertiary combustion zone for a third combustor load range between 35% combustor load and 50% combustor load; and interrupting the supply of gaseous fuel to the HE fuel nozzle set, the first AFS injector set, and the second AFS injector set between 50% combustor load and 100% combustor load.

[0023] Another aspect of the present disclosure includes any of the preceding aspects, wherein the controller operates the combustor in a second simultaneous firing operating mode, which includes the steps of: supplying fuel to an HE fuel nozzle set and introducing and burning gaseous fuel in a primary combustion zone for a first combustor load range from 0% combustor load to 50% combustor load; supplying fuel to a first AFS injector set and introducing and burning gaseous fuel in a secondary combustion zone for a second combustor load range from 10-20% combustor load to 50% combustor load; supplying fuel to a second AFS injector set and introducing and burning gaseous fuel in a tertiary combustion zone for a third combustor load range between 35% combustor load and 100% combustor load; and interrupting the supply of gaseous fuel to the HE fuel nozzle set and the first AFS injector set between 50% combustor load and 100% combustor load.

[0024] Another aspect of the present disclosure includes any of the preceding aspects, wherein the controller operates the combustor in a third simultaneous firing operating mode, which includes the steps of: supplying fuel to an HE fuel nozzle set and introducing and burning gaseous fuel in a primary combustion zone for a first combustor load range from 0% combustor load to 100% combustor load; supplying fuel to a first AFS injector set and introducing and burning gaseous fuel in a secondary combustion zone for a second combustor load range from 10-20% combustor load to 50% combustor load; supplying fuel to a second AFS injector set and introducing and burning gaseous fuel in a tertiary combustion zone for a third combustor load range between 35% combustor load and 100% combustor load; and interrupting the supply of gaseous fuel to the first AFS injector set between 50% combustor load and 100% combustor load.

[0025] Another aspect of the present disclosure includes any of the preceding aspects, wherein the controller operates the combustor in a fourth simultaneous firing operating mode, which includes the steps of: supplying fuel to an HE fuel nozzle set and introducing and burning gaseous fuel in a primary combustion zone for a first combustor load range from 0% combustor load to 100% combustor load; supplying fuel to a first AFS injector set and introducing and burning gaseous fuel in a secondary combustion zone for a second combustor load range from 10-20% combustor load to 100% combustor load; and supplying fuel to a second AFS injector set and introducing and burning gaseous fuel in a tertiary combustion zone for a third combustor load range between 35% combustor load and 100% combustor load.

[0026] Two or more embodiments described in this disclosure, including those described in this summary section, can be combined to form embodiments not specifically described herein. That is, all embodiments described herein can be combined with one another.

[0027] Details of one or more embodiments are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will be apparent from the description and drawings, and from the claims.

[0028] These and other features of the present disclosure will be more readily understood from the following detailed description of the various aspects of the present disclosure, taken in conjunction with the accompanying drawings that illustrate various embodiments of the present disclosure.

Brief Description of the Drawings

[0029] [Figure 1] FIG. 1 is a functional block diagram of an exemplary gas turbine system including a combustor according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is a simplified cross-sectional side view of an exemplary combustor according to an embodiment of the present disclosure. [Figure 3] FIG. 3 is a view of an upstream portion of a part of the combustor shown in FIG. 2 according to an embodiment of the present disclosure. [Figure 4] FIG. 4 is a bar graph representation of the operation of various parts of the combustor based on the combustor load percentage (%) according to an embodiment of the present disclosure. [[ID=二十三]] [Figure 5] FIG. 5 is a graphical representation of a transition occurring at 50% combustor load for the ammonia mode of FIG. 4 according to a particular embodiment of the present disclosure.

Modes for Carrying Out the Invention

[0030] Note that the drawings of the present disclosure are not necessarily drawn to scale. The drawings are intended to illustrate only typical aspects of the present disclosure and should not be considered as limiting the scope of the present disclosure. In the drawings, like reference numerals represent like elements among the drawings.

[0031] As a first issue, in order to clearly explain the current disclosure, it is necessary to select specific terminology when referring to and describing relevant mechanical components in exemplary applications of turbomechanical combustors. Where this is done, common industrial terminology will be used and adopted in a manner consistent with its accepted meaning, whenever possible. Unless otherwise stated, such terminology should be given a broad interpretation consistent with the context of this application and the appended claims. Those skilled in the art will understand that, in many cases, certain components may be referred to using several different or overlapping terms. What may be described herein as a single part may comprise multiple components and be referred to as consisting of multiple components in another context. Conversely, what may be described herein as comprising multiple components may be referred to elsewhere as a single part.

[0032] In addition, this specification may use several descriptive terms, and it will be useful to define these terms at the beginning of this section. These terms and their definitions are as follows, unless otherwise specified: As used herein, “downstream” and “upstream” are terms indicating direction relative to the working fluid through the combustor of a turbomachinery, or to the flow of fluid such as air, gaseous fuel, or ammonia through the combustor or nozzle, or coolant through one of the turbomachinery's component systems. The term “downstream” corresponds to the direction of the fluid flow, and the term “upstream” refers to the direction opposite to the flow. The terms “forward” and “rear” refer to direction, unless otherwise specified, with “forward” referring to the front of the turbomachinery or combustor or the compressor end, and “rear” referring to the rear of the turbomachinery or combustor or the turbine end.

[0033] The term “axial” refers to movement or position parallel to an axis, for example, the axis of a combustor, the mixing chamber of an AFS injector, or a turbomachinery. The term “radial” refers to movement or position perpendicular to an axis, for example, the axis of a combustor or turbomachinery. In such cases, if the first component is located closer to the axis than the second component, this specification states that the first component is “radially inward” or “inside” the second component. On the other hand, if the first component is located further from the axis than the second component, this specification may state that the first component is “radially outward” or “outside” the second component. Finally, the term “circumferential” refers to movement or position around an axis, for example, the circumferential inner surface of a combustor body or the circumferential interior of a casing extending around a combustor. As described above, depending on the context, it will be understood that such terms may be applied to the axis of a combustor, nozzle, or turbine.

[0034] In addition, several descriptive terms may be used periodically in this specification, as described below. The terms “first,” “second,” and “third” may be used interchangeably to distinguish one component from another and are not intended to indicate the location or importance of any individual component.

[0035] The technical terms used herein are for the sole purpose of describing specific embodiments and are not intended to limit this disclosure. Where used herein, the singular forms “a,” “an,” and “the” are intended to include the plural form unless the context otherwise explicitly indicates. Where used herein, the terms “comprises” and / or “comprising” express the existence of the described features, integers, steps, actions, elements, and / or components, but it will be further understood that they do not exclude the existence or addition of one or more other features, integers, steps, actions, elements, components, and / or sets thereof. “Optional” or “optionally” means that the events described later may or may not occur, or the features described later may or may not exist, and this statement means that it includes both instances in which the events occur or the features exist, and instances in which the events do not occur or the features do not exist.

[0036] When an element or layer is referred to as “on top of,” “engaged,” “connected,” “joined,” or “attached” to another element or layer, it may be directly on top of, engaged, connected, joined, or attached to the other element or layer, or there may be an intervening element or layer. Conversely, when an element is referred to as “directly on top of,” “directly engaged,” “directly connected,” or “directly joined” to another element or layer, there is no intervening element or layer. Other words used to describe the relationship between elements should be interpreted similarly (e.g., “between” vs. “directly between,” “adjacent” vs. “directly adjacent,” etc.). As used herein, the term “and / or” includes any combination of one or more of the related enumerated items. The verb forms “join” and “attach” may be used interchangeably herein.

[0037] Embodiments of the present disclosure provide methods for simultaneous firing of a combustor using gaseous fuel and liquid ammonia using various techniques. Each method fires the gaseous fuel in a primary combustion zone using a head-end fuel nozzle set, a secondary combustion zone using a first axial fuel stage (AFS) injector set, and / or a tertiary combustion zone using a second AFS injector set, across one or more combustor load ranges. The method transitions to simultaneous firing with ammonia using an ammonia sprayer. The method can transition to ammonia combustion alone or ammonia combustion with conventional gaseous fuel. Cross-flow of the first AFS injector set stabilizes the combustion of ammonia, and the second AFS injector set provides a quench effect. Each of these effects contributes to efficient ammonia combustion, with or without conventional gaseous fuel combustion.

[0038] Figure 1 shows a functional block diagram of an exemplary gas turbine (GT) system 90 into which various embodiments of the combustor 100 of the present disclosure can be incorporated. As shown, the GT system 90 typically includes an inlet section 102 which may include a series of filters, cooling coils, moisture separators, and / or other devices for purifying and otherwise conditioning the air 106 entering the GT system 90. The air 106 flows to a compressor 108 in a compressor section 110, which gradually imparts kinetic energy to the air 106 to generate high-pressure (HP) air 112 (hereinafter, "air 112", "HP air 112", or "compressed air 112") compressed in a high-energy state. The HP air 112 is typically mixed with one or more fuels from a fuel source 116, e.g., fuels 114A and / or 114B, to form a combustible mixture in at least one combustor 100 in a combustion section 120 operably coupled to the compressor section 110. The combustible mixture is burned to produce high-temperature, high-pressure combustion gases 122. The combustion gases 122 flow through a turbine 128 (e.g., an expansion turbine) in a turbine section 130 operably coupled to the combustion section 120, generating work. For example, the turbine 128 may be connected to a shaft 132 such that the rotation of the turbine 128 drives a compressor 108 to produce HP air 112. Alternatively or additionally, the shaft 132 may connect the turbine 128 to another load, such as a generator 134 for generating electricity. Exhaust gases 136 from the turbine 128 flow through an exhaust section 138 that connects the turbine 128 to an exhaust stack 140 downstream of the turbine 128. The exhaust section 138 may include, for example, a heat recovery boiler (not shown) for purifying and extracting additional heat from the exhaust gases 136 before they are released into the environment. If multiple combustors 100 are used (i.e., in a can ring arrangement), they can be arranged circumferentially at intervals around the turbine inlet 142 of the turbine 128.

[0039] In one embodiment, the GT system 90 may be applicable to engine models commercially available from GE Vernova in Cambridge, Massachusetts, and the method can be implemented in such engine models. The disclosure is not limited to any one specific GT system and can be implemented in relation to other engines, including, for example, any HA, F, B, LM, GT, TM, and E-class engine models from GE Vernova, as well as engine models from other companies. Furthermore, the disclosure is not limited to any specific turbomachinery and can be applied to, for example, steam turbines, jet engines, compressors, turbofans, and the like.

[0040] Next, an exemplary combustor 100 usable within the GT system 90 and its operation method will be described. Figure 2 shows a cross-sectional side view of the combustor 100 positioned within the GT system 90. As shown in Figure 2, the combustor 100 is at least partially enclosed by an outer casing 150, such as a compressor discharge casing and / or a turbine casing. The internal plenum 152 of the outer casing 150 is in fluid communication with the compressor discharge port 109 of the compressor 108, forming an HP air source 154. That is, the HP air source 154 contains HP air 112 from the compressor discharge port 109 of the compressor 108. The HP air source 154 is in direct fluid communication with the compressor discharge port 109 of the GT system 90. However, the HP air source 154 may be any source of HP air 112 that can flow into any various openings or passages in the combustor 100, for cooling components and / or for combustion, for example, using a head-end (HE) fuel nozzle set 182 or an axial fuel stage (AFS) injector set 180, 200 as described herein.

[0041] As shown in Figure 2, the combustor 100 for the GT system 90 includes a combustor body 160. The combustor body 160 can be fabricated using any currently known or future-developed technique. For example, the combustor body 160 can be additively fabricated and may include a single-piece member 162 having a double-wall structure, as described below. The combustor body 160 may include a combustion liner 164, which may include, for example, a cylindrical portion 166 and a tapered transition portion 168. One or more liners or ducts can at least partially define a combustion reaction zone 186 (also referred to herein as a combustion chamber 186) for burning one or more fuel-air mixtures and form a combustion liner 164 that can at least partially define a high-temperature gas path (HGP) through the combustor 100 for directing combustion gases 122 toward the turbine inlet 142 and then to the turbine 128. The tapered transition portion 168 is located at the rear end of the cylindrical portion 166 (on the right in Figure 2). As understood in the art, the tapered transition section 168 transitions the HGP from a circular cross-section to a more arched cross-section of the cylindrical section 166 of the liner in order to engage with the turbine inlet 142 of the turbine 128. The combustor 100 may also include a rear frame 167 at the rear end (right side in Figure 2) of the tapered transition section 168.

[0042] The combustion liner 164 may have a separate tapered transition section 168 from the cylindrical section 166, as in many conventional combustion systems. Alternatively, as shown in Figure 2, the combustion liner 164 may have a unibody structure in which the cylindrical section 166 and the tapered transition section 168 are integrated with each other, i.e., as part of an additively manufactured integral member 162. Therefore, any description of the combustion liner 164 in this specification is intended to encompass both conventional combustion systems having separate cylindrical and tapered transition sections and combustion systems having a unibody liner. In any case, during operation, the combustion liner 164 can contain the combustion gas 122 and transport it to the turbine section 130 (Figure 1). More specifically, the combustion liner 164 defines the combustion chamber 186, i.e., the HGP, in which combustion takes place. The combustion gas 122 may include the combustion gas fuels 114A and / or ammonia 114B described herein.

[0043] The combustor body 160 also includes an air passage 170, at least partially defined by a cylindrical portion 166 of the combustion liner 164 (e.g., between the inner and outer walls of a double-wall structure). As described herein, the air passage 170 is configured to deliver HP air 112A from the HP air source 154 to the head-end assembly 172 of the combustor 100 at the front end of the combustion liner 164 (left end in Figure 2). That is, it is sized, shaped, and / or arranged to deliver HP air 112A from the HP air source 154 to the head-end assembly 172 of the combustor 100, i.e., to the high-pressure plenum 174 of the head-end assembly 172. The air passage 170 may be defined entirely within the cylindrical portion 166, or the air passage 170 may be provided between the cylindrical portion 166 and a flow sleeve 176 spaced along at least a portion of the outer surface of the cylindrical portion 166. The air passage 170 has an open end 178 upstream of the first axial fuel stage (AFS) injector set 180 (i.e., combustor 100), into which HP air 112A from the HP air source 154 enters, for example.

[0044] The head-end assembly 172 includes a head-end (HE) fuel nozzle or burner set 182 (hereinafter, "HE nozzle set 182") which includes a plurality of nozzles 184. Each nozzle 184 directs gaseous fuel 114A and air 112A to the combustion reaction zone 186 of the combustor 100. Each nozzle 184 may include any currently known or future-developed swozle-based or micro-mixer-based nozzle. The combustion reaction zone 186 may include a primary combustion zone 188 in the combustion liner 164. In certain embodiments, although not shown, HE fuel nozzles 184 extending axially from the head-end assembly 172 may extend at least partially through the cap assembly 190 to supply a combustible mixture of gaseous fuel 114A and HP air 112A to the primary combustion zone 188 of the combustion reaction zone 186 in the combustion liner 164. The gaseous fuel 114A may include natural gas other than ammonia or any other gaseous fuel, which is typically used in the combustor 100. The gaseous fuel 114A may be delivered from the fuel source 116 using any form of fuel line 195.

[0045] The combustor 100 also includes a first axial fuel stage (AFS) injector set 180 directed to the combustion liner 164 downstream of the head-end assembly 172. Each AFS injector 192 in set 180 receives air 112B from the HP air source 154 and gaseous fuel 114A from the fuel source 116, possibly among other airflows. Note that air 112A is directed to the HP air plenum 174 in the head-end assembly 172, and air 112B is directed to the AFS injector sets 180 and 200. The first AFS injector set 180 burns the gaseous fuel 114A and HP air 112B in the secondary combustion zone 194 of the combustion reaction zone 186 within the combustion liner 164. The gaseous fuel 114A may be delivered from the fuel source 116 using any form of fuel line 196. As shown in the figure, the first AFS injector set 180 may include a plurality of AFS injectors 192 arranged at circumferential intervals. Any number of AFS injectors 192 can be used in the first AFS injector set 180. For example, the AFS injector set 180 may include a plurality of AFS injectors 192 arranged at circumferential intervals around the combustor body 160. Each AFS injector 192 extends radially through the combustion liner 164 downstream of the head-end assembly 172, i.e., downstream of the axially extending HE nozzle set 182.

[0046] The combustor 100 also includes a second axial fuel stage (AFS) injector set 200 directed toward the combustion liner 164 downstream of the first AFS injector set 180. Each AFS injector 202 of set 200 receives HP air 112B from an HP air source 154 and gaseous fuel 114A from a fuel source 116, possibly among other airflows. The second AFS injector set 200 burns the gaseous fuel 114A and HP air 112B in a tertiary combustion zone 204 of the combustion reaction zone 186 within the combustion liner 164. The gaseous fuel 114A may be delivered from the fuel source 116 using any form of fuel line 206. As shown, the second AFS injector set 200 may include a plurality of circumferentially spaced AFS injectors 202. Any number of AFS injectors 202 can be used in the second AFS injector set 200. For example, the AFS injector set 200 may include a plurality of AFS injectors 202 arranged circumferentially around the combustor body 160 at intervals. Each AFS injector 202 extends radially through the combustion liner 164 downstream of the first AFS injector set 180 and the head-end assembly 172, i.e., downstream of the axially extending HE nozzle set 182.

[0047] The combustor 100 also includes an ammonia sprayer 210 (i.e., one or more sprayers 210) directed toward the combustion liner 164 to burn liquid ammonia 114B in at least the primary combustion zone 188. The ammonia sprayer 210 may include any currently known or hereafter developed sprayer structures capable of producing a mist of liquid ammonia. The ammonia sprayer 210 may include any number or form of nozzles for producing the desired ammonia mist. As shown, the ammonia sprayer 210 may be centrally located within the head-end plenum 174 so that the sprayed ammonia is distributed relatively uniformly and radially in the primary combustion zone 188.

[0048] Figure 3 shows an upstream view of a portion of the combustor shown in Figure 2, according to an embodiment of the present disclosure. In various embodiments, as collectively shown in Figures 2 and 3, the combustor 100 includes an HE fuel nozzle set 182, which includes a plurality of nozzles 184, with their upstream ends coupled to an end cover 212 and extending toward a combustion reaction zone 186. The downstream ends of the HE fuel nozzles 184 are aligned with their respective openings (not separately labeled) in a cap assembly 190 so that the HE fuel nozzles 184 deliver a fuel / air mixture to a combustion liner 164. Similarly, the combustor 100 includes an ammonia sprayer 210, with its upstream end coupled to or extending through the end cover 212 and directed toward the combustion reaction zone 186. The downstream end of the ammonia sprayer 210 is aligned with their respective openings (not separately labeled) in a cap assembly 190 so that the ammonia sprayer 210 delivers liquid ammonia to the combustion liner 164 in a spray or mist.

[0049] Various embodiments of the combustor 100 may include different numbers and arrangements of HE fuel nozzles 184 and ammonia sprayers 210, and the embodiments described herein are not limited to any particular number of nozzles or sprayers unless specifically specified in the claims. For example, in a particular configuration such as the one shown in Figure 3, the HE fuel nozzle set 182 includes HE fuel nozzles 184 arranged in an annular configuration with a central HE fuel nozzle 214. In other embodiments, the HE fuel nozzles 184 may be arranged in an annular configuration around the centerline of the end cover 212 without using the central HE fuel nozzle 214. The central HE fuel nozzle 214 may also be a premixed multi-fuel (liquid and gaseous fuel) type nozzle. Each HE fuel nozzle 184, 214 may be a swazzle-based nozzle or a micro-mixer-based nozzle, as those terms are understood in the art. In any case, each HE fuel nozzle 184, 214 can be used to mix a gaseous fuel 114A, such as natural gas or other gaseous fuel, with air 112A, or simply to allow air 112A to pass through.

[0050] With respect to fuel delivery, the combustor controller 220 (Figure 2) controls the operation of various pumps and / or valves (not shown) to control the delivery of gaseous fuel 114A and / or ammonia 114B through fuel lines 195, 196, and 206 and / or ammonia 114B through fuel line 216. The operation of the pumps and / or valves is known in the art among other gaseous fuel or liquid ammonia delivery structures, so further details are not provided. The controller 220 is operably coupled to any of the necessary pumps, valves, fuel lines, and other fuel delivery structures to control its operation in accordance with embodiments of this disclosure. The controller 220 may include any hardware and / or software configured to control the function of the components of the combustor 100 described herein. Thus, where the combustor 100 is shown to perform a particular function, the controller 220 may control the above function through the control of any other structure or feedback sensor, such as pumps, fans, valves, fuel lines, igniters, or fluid control vanes, but is not limited to these.

[0051] As shown in Figures 1 to 3, the combustor 100 includes an HE fuel nozzle set 182 directed towards the combustion liner 164 to burn fuel in a primary combustion zone 188, a first AFS injector set 180 directed towards the combustion liner 164 to burn fuel in a secondary combustion zone 194 downstream of the primary combustion zone 188, and a second AFS injector set 200 directed towards the combustion liner 164 to burn fuel in a tertiary combustion zone 204 downstream of the secondary combustion zone 194. Furthermore, the combustor 100 includes an ammonia sprayer 210 directed towards the combustion liner 164 to burn ammonia 114B in at least the primary combustion zone 188, and optionally in downstream combustion zones 194, 204 where complete ammonia combustion does not occur in the primary combustion zone 188.

[0052] Figure 4 shows a bar graph representation of the operation of various parts of the combustor 100 based on combustor load percentage (%). In particular, Figure 4 shows the operation of the HE fuel nozzle set 182, the first AFS injector set 180, the second AFS injector set 200, and the ammonia sprayer 210. The legend in Figure 4 shows cross-hatching indicators for each part of the combustor 100 (Figure 2). Figure 4 is used to illustrate the method according to embodiments of the present disclosure. As used herein, “combustor load” refers to the ratio of the amount of combustion gas produced to the maximum amount of combustion gas that the combustor 100 can produce, based, for example, on the intake of combustion gas 122 required to meet the demands of the turbine 128. The combustor load is expressed as a percentage or a percentage range. It will be recognized that the operation of the combustor 100 as described herein, i.e., the operation according to the method described herein, is controlled by the controller 220 (Figure 2).

[0053] The ammonia (NH3) mode is indicated by the top bar set in Figure 4. Referring to Figures 2 and 4, during the ammonia mode, the combustor 100 performs the following under the control of the controller 220: For a first combustor load range from 0% to 50%, the combustor 100 burns gaseous fuel 114A in the primary combustion zone 188 using the HE fuel nozzle set 182. Here, the gaseous fuel 114A is delivered to the HE fuel nozzle set 182, mixed with air 112A, and then directed to the combustion liner 164, i.e., the primary combustion zone 188 in the combustion reaction zone 186, where it is burned. For a second combustor load range from 10-20% to 50%, the combustor 100 further burns the gaseous fuel 114A in the secondary combustion zone 194 using the first AFS injector set 180. Here, the gaseous fuel 114A is delivered to the first AFS injector set 180, mixed with air 112B, and directed to the combustion liner 164, i.e., the secondary combustion zone 194 in the combustion reaction zone 186, where it is burned. For a third combustor load range between 35% and 50% combustor load, the combustor 100 further burns the gaseous fuel 114A in the tertiary combustion zone 204 using the second AFS injector set 200. Here, the gaseous fuel 114A is delivered to the second AFS injector set 200, mixed with air 112B, and directed to the combustion liner 164, i.e., the tertiary combustion zone 204 in the combustion reaction zone 186, where it is burned.

[0054] At a 50% combustor load, the combustion transitions to ammonia 114B. More specifically, as shown in Figure 4, at a 50% combustor load, the transition occurs by using the HE fuel nozzle set 182, the first AFS injector set 180, and the second AFS injector set 200 to stop the combustion of gaseous fuel 114A and using the ammonia sprayer 210 to initiate the combustion of ammonia 114B in at least the primary combustion zone 188. The "at least" in this setting indicates that ammonia 114B can burn primarily in the primary combustion zone 188, but some ammonia 114B can move to the secondary combustion zone 194 and / or tertiary combustion zone 204 to burn. For a fourth combustor load range between a combustor load above 50% and a combustor load of 100%, the combustor 100 uses the ammonia sprayer 210 to burn only ammonia 114B in at least the primary combustion zone 188. Here, gaseous fuel 114A does not flow to the HE fuel nozzle set 182, the first AFS injector set 180, and the second AFS injector set 200. Air 112A may continue to flow from the HE fuel nozzle set 182, the first AFS injector set 180, and / or the second AFS injector set 200 to assist combustion.

[0055] Figure 5 shows a graphical representation of the transition occurring at a 50% combustor load for the ammonia mode of Figure 4, according to a particular embodiment of the present disclosure. Figure 5 shows the fuel mass flow rate (FMFR) to various parts of the combustor 100 over time while at a 50% combustor load. Referring to Figures 2 and 5, the transition begins, for example, by the controller 220 increasing the ammonia flow rate to the ammonia sprayer 210, thereby gradually increasing the FMFR of ammonia 114B to the ammonia sprayer 210. As used herein, “gradually” means that the described action occurs over a period of time and is not immediate or abrupt. While the FMFR of ammonia 114B to the ammonia sprayer 210 is gradually increasing, many FMFR decreases occur in other parts of the combustor 100. More specifically, the controller 220 gradually decreases the FMFR of gaseous fuel 114A to the HE fuel nozzle set 182 to zero, for example, starting at time T1 and extending to time T2. After the supply of gas fuel 114A to the HE fuel nozzle set 180 is stopped (time T2), the controller 220 gradually reduces the FMFR of gas fuel 114A to the first AFS injector set 180 to zero, for example, from time T3 to time T4. This part of the transition may further include temporarily maintaining the FMFR of ammonia 114B to the ammonia sprayer 210 at current level 300 (time T2 to time T3) before starting the gradual reduction of the FMFR of gas fuel 114A to the first AFS injector set 180 to zero (time T3 to time T4), and continuing the gradual increase of the FMFR of ammonia 114B to the ammonia sprayer 210 (time T3 to time T4) after (and during) starting the gradual reduction of the FMFR of gas fuel 114A to the first AFS injector set 180 to zero (time T3 to time T4).

[0056] After stopping the supply of gas fuel 114A to the first AFS injector set 180 (time T4), the controller 220 gradually reduces the FMFR of gas fuel 114A to the second AFS injector set 200 to zero (from time T5 to time T6). This part of the transition may further include temporarily maintaining the FMFR of ammonia 114B to the ammonia sprayer 210 at current level 302 before initiating the gradual reduction of the FMFR of gas fuel 114A to the second AFS injector set 200 to zero (from time T5 to time T6), and continuing the gradual increase of the FMFR of ammonia 114B to the ammonia sprayer 210 (from time T5 to time T6) after (and during) initiating the gradual reduction of the FMFR of gas fuel 114A to the second AFS injector set 200 to zero (from time T5 to time T6).

[0057] When ammonia 114B is injected by the ammonia sprayer 210, it vaporizes in the combustion reaction zone 186 near the first AFS injector set 180. At this stage, the ammonia-to-air ratio is very rich, for example, 1.1 to 1.5:1. The gas-fuel-air mixture or air injected by the first AFS injector set 180 helps stabilize the flame in the primary combustion zone 188. In addition, the gas-fuel-air mixture or air from the HE fuel nozzle set 182, for example, a micromixer, also helps atomize ammonia 114B and improves combustion in the primary combustion zone 188. The transition further includes setting the FMFR of ammonia 114B to the ammonia sprayer 210 to the maximum desired level 304 in response to the FMFR of gas-fuel 114A to the second AFS injector set 200 reaching zero (time T6). That is, the controller 220 can force the two generation to occur simultaneously or nearly simultaneously.

[0058] Returning to Figures 2 and 4, for the fourth combustor load range (ammonia mode) between 50% and 100% combustor load, the flow of gaseous fuel 114A to the HE fuel nozzle set 182, the first AFS injector set 180, or the second AFS injector set 200 is stopped. Here, only ammonia 114B is injected by the ammonia sprayer 210 and combusted in the combustion reaction zone 186. However, air 112A continues to be injected into the combustion liner 164 using the HE fuel nozzle set 182, and air 112B continues to be injected into the combustion liner 164 using the first AFS injector set 180 and the second AFS injector set 200. That is, when the flow of gaseous fuel 114A to the HE fuel nozzle set 182, the first AFS injector set 180, or the second AFS injector set 200 is stopped, they inject only air 112A, 112B. The air injection further improves the atomization of ammonia to improve combustion in any relevant combustion zones 188, 194, 204.

[0059] Continuing to refer to Figures 2 and 4, simultaneous firing mode 1 is shown by the second set of bars from the top in Figure 4. During simultaneous firing mode 1, the combustor 100, under the control of the controller 220, performs the following: For a first combustor load range from 0% to 50%, the combustor 100 burns gaseous fuel 114A in the primary combustion zone 188 using the HE fuel nozzle set 182. Here, the gaseous fuel 114A is delivered to the HE fuel nozzle set 182, mixed with air 112A, and then directed to the combustion liner 164, i.e., the primary combustion zone 188 in the combustion reaction zone 186, where it is burned. For a second combustor load range from 10-20% to 50%, the combustor 100 further burns the gaseous fuel 114A in the secondary combustion zone 194 using the first AFS injector set 180. Here, the gaseous fuel 114A is delivered to the first AFS injector set 180, mixed with air 112B, and directed to the combustion liner 164, i.e., the secondary combustion zone 194 in the combustion reaction zone 186, where it is burned. For a third combustor load range between 35% and 50% combustor load, the combustor 100 further burns the gaseous fuel 114A in the tertiary combustion zone 204 using the second AFS injector set 200. Here, the gaseous fuel 114A is delivered to the second AFS injector set 200, mixed with air 112B, and directed to the combustion liner 164, i.e., the tertiary combustion zone 204 in the combustion reaction zone 186, where it is burned. For a fourth combustor load range between 20% and 100% combustor load, the combustor 100 burns ammonia 114B in at least the primary combustion zone 188 using the ammonia sprayer 210. As described above, ammonia 114B can be burned primarily in the primary combustion zone 188, but some ammonia 114B can move to the secondary combustion zone 194 and / or tertiary combustion zone 204 for combustion. As shown in Figure 4, at a 50% combustor load, the transition occurs by stopping the combustion of gaseous fuel 114A using the HE fuel nozzle set 182, the first AFS injector set 180, and the second AFS injector set 200.Here, gaseous fuel 114A does not flow to the HE fuel nozzle set 182, the first AFS injector set 180, and the second AFS injector set 200. Air 112A may continue to flow from the HE fuel nozzle set 182, the first AFS injector set 180, and / or the second AFS injector set 200 to assist combustion.

[0060] Continuing to refer to Figures 2 and 4, simultaneous firing mode 2 is indicated by the third set of bars from the top in Figure 4. During simultaneous firing mode 2, the combustor 100, under the control of the controller 220, performs the following: For a first combustor load range from 0% to 50%, the combustor 100 burns gaseous fuel 114A in the primary combustion zone 188 using the HE fuel nozzle set 182. Here, the gaseous fuel 114A is delivered to the HE fuel nozzle set 182, mixed with air 112A, and then guided to the combustion liner 164, i.e., the primary combustion zone 188 in the combustion reaction zone 186, where it is burned. For a second combustor load range from 10-20% to 50%, the combustor 100 further burns the gaseous fuel 114A in the secondary combustion zone 194 using the first AFS injector set 180. Here, the gaseous fuel 114A is delivered to the first AFS injector set 180, mixed with air 112B, and directed to the combustion liner 164, i.e., the secondary combustion zone 194 in the combustion reaction zone 186, where it is burned. For a third combustor load range between 35% and 100% combustor load, the combustor 100 uses the second AFS injector set 200 to further burn the gaseous fuel 114A in the tertiary combustion zone 204. Here, the gaseous fuel 114A is delivered to the second AFS injector set 200, mixed with air 112B, and directed to the combustion liner 164, i.e., the tertiary combustion zone 204 in the combustion reaction zone 186, where it is burned.

[0061] At a 50% combustor load, the combustor 100, under the control of the controller 220, stops the combustion of gas fuel 114A using the HE fuel nozzle set 182 and the first AFS injector set 180. Here, the gas fuel 114A is stopped up to the HE fuel nozzle set 182 and the first AFS injector set 180, but continues to flow up to the second AFS injector set 200. For a fourth combustor load range between 20% and 100% combustor load, the combustor 100 burns ammonia 114B in at least the primary combustion zone 188 using the ammonia sprayer 210, along with the combustion of gas fuel 114A in the tertiary combustion zone 204 using the second AFS injector set 200. Therefore, the gaseous fuel 114A continues to be delivered to the second AFS injector set 200, mixed with air 112B, and directed to the combustion liner 164, i.e., the tertiary combustion zone 204 in the combustion reaction zone 186, for combustion. However, between 50% and 100% combustor load, air 112A is injected using the HE fuel nozzle set 182, and air 112B is injected by the first AFS injector set 180. Due to the HE fuel nozzle set 182 and the first AFS injector set 180 not delivering gaseous fuel 114A between 50% and 100% combustor load, the gaseous fuel fraction of the total fuel amount is less than 20% during this part of simultaneous firing mode 2.

[0062] Continuing to refer to Figures 2 and 4, simultaneous firing mode 3 is indicated by the fourth set of bars from the top in Figure 4. During simultaneous firing mode 3, the combustor 100 performs the following under the control of the controller 220: For a first combustor load range from 0% to 100% combustor load, the combustor 100 burns gaseous fuel 114A in the primary combustion zone 188 using the HE fuel nozzle set 182. Here, the gaseous fuel 114A is delivered to the HE fuel nozzle set 182, mixed with air 112A, and then directed to the combustion liner 164, i.e., the primary combustion zone 188 in the combustion reaction zone 186, where it is burned. For a second combustor load range from 10-20% to 50% combustor load, the combustor 100 further burns the gaseous fuel 114A in the secondary combustion zone 194 using the first AFS injector set 180. Here, the gaseous fuel 114A is delivered to the first AFS injector set 180, mixed with air 112B, and directed to the combustion liner 164, i.e., the secondary combustion zone 194 in the combustion reaction zone 186, where it is burned. For a third combustor load range between 35% and 100% combustor load, the combustor 100 uses the second AFS injector set 200 to further burn the gaseous fuel 114A in the tertiary combustion zone 204. Here, the gaseous fuel 114A is delivered to the second AFS injector set 200, mixed with air 112B, and directed to the combustion liner 164, i.e., the tertiary combustion zone 204 in the combustion reaction zone 186, where it is burned.

[0063] At a 50% combustor load, the combustor 100 stops the combustion of gas fuel 114A using the first AFS injector set 180. Here, the gas fuel 114A is stopped up to the first AFS injector set 180 but continues to flow to the HE fuel nozzle set 182 and the second AFS injector set 200. For a fourth combustor load range between 20% and 100% combustor load, the combustor 100 burns ammonia 114B in at least the primary combustion zone 188 using the ammonia sprayer 210, along with the combustion of gas fuel 114A in the primary combustion zone 188 using the HE fuel nozzle set 182 and the tertiary combustion zone 204 using the second AFS injector set 200. Therefore, the gaseous fuel 114A continues to be delivered to the HE fuel nozzle set 182 and the second AFS injector set 200, mixed with air 112A and 112B, and guided to the combustion liner 164, i.e., the primary combustion zone 188 and tertiary combustion zone 204 in the combustion reaction zone 186, for combustion. However, between 50% and 100% combustor load, only air 112B is injected using the first AFS injector set 180. Due to the first AFS injector set 180 not delivering gaseous fuel 114A between 50% and 100% combustor load, the gaseous fuel fraction of the total fuel amount is 20% to 50% during this part of simultaneous firing mode 3.

[0064] Continuing to refer to Figures 2 and 4, simultaneous firing mode 4 is indicated by the bottom bar set in Figure 4. During simultaneous firing mode 4, the combustor 100, under the control of the controller 220, performs the following: For a first combustor load range from 0% combustor load to 100% combustor load, the combustor 100 burns gaseous fuel 114A in the primary combustion zone 188 using the HE fuel nozzle set 182. Here, the gaseous fuel 114A is delivered to the HE fuel nozzle set 182, mixed with air 112A, and then guided to the combustion liner 164, i.e., the primary combustion zone 188 in the combustion reaction zone 186, where it is burned. For a second combustor load range between 10-20% combustor load and 100% combustor load, the combustor 100 further burns gaseous fuel 114A in the secondary combustion zone 194 using the first AFS injector set 180. Here, the gaseous fuel 114A is delivered to the first AFS injector set 180, mixed with air 112B, and directed to the combustion liner 164, i.e., the secondary combustion zone 194 in the combustion reaction zone 186, where it is burned. For a third combustor load range between 35% and 100% combustor load, the combustor 100 uses the second AFS injector set 200 to further burn the gaseous fuel 114A in the tertiary combustion zone 204. Here, the gaseous fuel 114A is delivered to the second AFS injector set 200, mixed with air 112B, and directed to the combustion liner 164, i.e., the tertiary combustion zone 204 in the combustion reaction zone 186, where it is burned.

[0065] For a fourth combustor load range between 20% and 100% combustor load, the combustor 100 further burns ammonia in at least the primary combustion zone 188 using the ammonia sprayer 210, while burning gaseous fuel 114A in the primary combustion zone 188 using the HE fuel nozzle set 182, in the secondary combustion zone 194 using the first AFS injector set 180, and in the tertiary combustion zone 204 using the second AFS injector set 200. Thus, the gaseous fuel 114A continues to be delivered to the HE fuel nozzle set 182, the first AFS injector set 180, and the second AFS injector set 200, mixed with air 112A or 112B, and then directed to the combustion liner 164, i.e., the primary combustion zone 188, the secondary combustion zone 194, and the tertiary combustion zone 204 in the combustion reaction zone 186. As a result, between 50% and 100% combustor load, the gas fuel fraction of the total fuel exceeds 50% during this portion of simultaneous firing mode 4.

[0066] In an alternative operating mode, the ammonia sprayer 210 can be used to inject diesel fuel or any other liquid fuel, which can then be burned with air either as a standalone fuel or in simultaneous firing with natural gas.

[0067] This disclosure provides various technical and commercial advantages, examples of which are described herein. Embodiments of the method provide efficient ammonia combustion with or without gaseous fuel combustion. As described above, the cross-flow of the first AFS injector set stabilizes the combustion of ammonia, and the second AFS injector set provides a quench effect. Each of these effects contributes to efficient ammonia combustion with or without gaseous fuel combustion.

[0068] Throughout this specification and the claims, the approximation language can be applied to modify any quantitative expression that can vary to a reasonable extent without altering the fundamental function of the expression. Thus, values ​​modified by terms such as “approximately,” “about,” and “substantially” are not limited to the exact value specified. In at least some examples, the approximation language may correspond to the precision of the instrument used to measure the value. Here, and throughout this specification and the claims, limitations on ranges are interchangeable and / or replaceable, and unless the context or wording specifically indicates otherwise, such ranges are identified and include all subranges encompassed therein. “Approximately” or “about” applied to a particular value within a range may indicate + / - 10% of the stated value, unless applied to the values ​​at both ends and particularly dependent on the precision of the instrument used to measure the value.

[0069] All means or step-plus-function elements in the following claims are intended to include any structures, materials, or actions for performing a function in combination with other claimed elements specifically claimed. The descriptions in this disclosure are presented for illustrative and explanatory purposes and are not intended to be exhaustive or to limit the disclosure to the forms disclosed herein. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of this disclosure. The embodiments have been selected and described to best illustrate the principles of this disclosure and the practical applications of the art, and to enable those skilled in the art to understand this disclosure in order to consider various modifications to these embodiments that may be suitable for the particular use under consideration. [Explanation of symbols]

[0070] 90 Gas turbine (GT) systems, turbomachinery 100 Combustor 102 Entrance Section 106 Air 108 Compressor 109 Compressor discharge port 110 Compressor Section 112 Compressed high-pressure (HP) air 112A Compressed high-pressure (HP) air 112B Compressed high-pressure (HP) air 114A Combustion gas fuel 114B Fuel, liquid ammonia 116 Fuel source 120 Combustion Sections 122 Combustion gases 128 Turbine 130 Turbine Section 132 shaft 134 Generators 136 Exhaust gas 138 Exhaust Section 140 exhaust stack 142 Turbine Inlet 150 Outer casing 152 Internal Plenum 154 HP air source 160 Combustion Unit 162 Integrated component 164 Combustion Liner 166 Cylindrical section 167 Rear frame 168 Tapered transition section 170 Airflow channel 172 Head End Assembly 174 High-voltage plenum, head-end plenum 176 Flow Sleeve 178 Open end 180 First Axial Fuel Stage (AFS) Injector Set 182 Head End (HE) Fuel Nozzle, Burner Set 184 HE Fuel Nozzle 186 Combustion reaction zone, combustion chamber 188 Primary Combustion Zone 190 Cap Assembly 192 AFS Injector 194 Secondary combustion zone, downstream combustion zone 195 Fuel line 196 Fuel line 200 Second AFS Injector Set 202 AFS Injector 204 Tertiary combustion zone, downstream combustion zone 206 Fuel line 210 Ammonia sprayer 212 End cover 214 Central HE fuel nozzle 216 Fuel line 220 Combustor Controller 300 Current Level 302 Current Level 304 Maximum desired level

Claims

1. In a combustor (100) including a head-end (HE) fuel nozzle set (182) directed toward the combustion liner (164) for burning fuel in a primary combustion zone (188), a first axial fuel stage (AFS) injector set (180) directed toward the combustion liner (164) for burning fuel in a secondary combustion zone (194) downstream of the primary combustion zone (188), a second AFS injector set (200) directed toward the combustion liner (164) for burning fuel in a tertiary combustion zone (204) downstream of the secondary combustion zone (194), and an ammonia sprayer (210) directed toward the combustion liner (164) for burning ammonia (114B) in at least the primary combustion zone (188), during a first simultaneous firing mode, For a first combustor load range from 0% combustor load to 50% combustor load, the steps include supplying fuel to the HE fuel nozzle set (182) and introducing gaseous fuel (114A) into the primary combustion zone (188) for combustion, For a second combustor load range from 10-20% combustor load to 50% combustor load, the first AFS injector set (180) is supplied with additional fuel, and the gaseous fuel (114A) is introduced into the secondary combustion zone (194) and burned. The steps include supplying additional fuel to the second AFS injector set (200) in a third combustor load range between a 35% combustor load and the 50% combustor load, and introducing the gaseous fuel (114A) into the tertiary combustion zone (204) for combustion, For a fourth combustor load range between 20% combustor load and 100% combustor load, the steps include supplying fuel to the ammonia sprayer (210) and introducing ammonia (114B) into at least the primary combustion zone (188) for combustion, and To implement Methods that include...

2. The method according to claim 1, further comprising: transitioning from the first simultaneous firing mode to ammonia fuel operation at the 50% combustor load by stopping the fuel supply to the HE fuel nozzle set (182), the first AFS injector set (180), and the second AFS injector set (200); and injecting only air (112, 112A, 112B) using the HE fuel nozzle set (182), the first AFS injector set (180), and the second AFS injector set (200) between the 50% combustor load and the 100% combustor load.

3. The method according to claim 2, wherein the transition involves gradually increasing the fuel mass flow rate (FMFR) of ammonia (114B) to the ammonia sprayer (210), then gradually decreasing the FMFR of the gas fuel (114A) to the HE fuel nozzle set (182) to zero, then gradually decreasing the FMFR of the gas fuel (114A) to the first AFS injector set (180) to zero, and then gradually decreasing the FMFR of the gas fuel (114A) to the second AFS injector set (200).

4. The aforementioned transition is Before initiating the gradual decrease in the FMFR of the gas fuel (114A) to the first AFS injector set (180) toward zero, the FMFR of the ammonia (114B) to the ammonia sprayer (210) is temporarily maintained at a first current level (300), and after initiating the gradual decrease in the FMFR of the gas fuel (114A) to the first AFS injector set (180) toward zero, the gradual increase in the FMFR of the ammonia to the ammonia sprayer (210) is continued. Before initiating the gradual decrease in the FMFR of the gas fuel (114A) to the second AFS injector set (200) toward zero, the FMFR of the ammonia to the ammonia sprayer (210) is temporarily maintained at a second current level (302), and after initiating the gradual decrease in the FMFR of the gas fuel (114A) to the second AFS injector set (200) toward zero, the gradual increase in the FMFR of the ammonia (114B) to the ammonia sprayer (210) is continued. In response to the FMFR of the gas fuel (114A) to the second AFS injector set (200) reaching zero, the FMFR of the ammonia (114B) to the ammonia sprayer (210) is set to the maximum desired level (304). The method according to claim 3, further comprising:

5. During the second simultaneous firing mode, the method is The method according to claim 1, comprising supplying fuel to the second AFS injector set (200), and introducing and burning the gaseous fuel (114A) in the tertiary combustion zone (204) within the combustor load range between the 50% combustor load and the 100% combustor load.

6. The method according to claim 5, further comprising injecting only air (112, 112A, 112B) using the HE fuel nozzle set (182) and the first AFS injector set (180) between the 50% combustor load and the 100% combustor load, wherein the gas fuel fraction of the total fuel amount is less than 20%.

7. During the third simultaneous firing mode, the method is Fuel is supplied to the HE fuel nozzle set (182), and gaseous fuel (114A) is introduced into the primary combustion zone (188) and burned in the combustor load range from 50% combustor load to 100% combustor load, In the combustor load range from 50% combustor load to 100% combustor load, only air (112, 112A, 112B) is injected into the secondary combustion zone (194) using the first AFS injector set (180), Fuel is supplied to the second AFS injector set (200), and the gaseous fuel (114A) is introduced into the tertiary combustion zone (204) and burned in the combustor load range between the 50% combustor load and the 100% combustor load. The method according to claim 1, including the method described in claim 1.

8. The method according to claim 7, wherein, in the third simultaneous firing mode, the gas fuel fraction of the total fuel amount is 20% to 50% between the 50% combustor load and the 100% combustor load.

9. During the fourth simultaneous firing mode, the method is Fuel is supplied to the HE fuel nozzle set (182), and gaseous fuel is introduced and burned in the primary combustion zone (188) between the 50% combustor load and the 100% combustor load. Fuel is supplied to the first AFS injector set (180), and the gaseous fuel is introduced and burned in the secondary combustion zone (194) between the 50% combustor load and the 100% combustor load. The second AFS injector set (200) is supplied with fuel, and the gaseous fuel is introduced and burned in the tertiary combustion zone (204) between the 50% combustor load and the 100% combustor load. The method according to claim 1, including the method according to claim 1.

10. The method according to claim 9, wherein, in the fourth simultaneous firing mode, the gas fuel fraction of the total fuel amount is greater than 50% between the 50% combustor load and the 100% combustor load.

11. A combustor (100) for a turbomachinery (90), A head end (HE) fuel nozzle set (182) directed towards the combustion liner (164) for burning fuel in the primary combustion zone (188), A first axial fuel stage (AFS) injector set (180) directed toward the combustion liner (164) to burn fuel in the secondary combustion zone (194) downstream of the primary combustion zone (188), A second AFS injector set (200) directed towards the combustion liner (164) for burning fuel in a tertiary combustion zone (204) downstream of the secondary combustion zone (194), An ammonia sprayer (210) directed towards the combustion liner (164) to burn ammonia (114B) in at least the primary combustion zone (188), Gas fuel (114A) is sequentially supplied to the HE fuel nozzle set (182), the first AFS injector set (180), and the second AFS injector set (200). Ammonia (114B) is supplied to the ammonia sprayer (210) as ammonia fuel from 20% combustor load to 100% combustor load. A controller (220) configured as follows and A combustion device (100) equipped with the above.

12. The controller (220) is For a first combustor load range from 0% combustor load to 50% combustor load, the steps include supplying fuel to the HE fuel nozzle set (182) and introducing the gaseous fuel (114A) into the primary combustion zone (188) for combustion, The steps include supplying fuel to the first AFS injector set (180) and introducing the gaseous fuel (114A) into the secondary combustion zone (194) for a second combustor load range from 10-20% combustor load to 50% combustor load, The steps include supplying fuel to the second AFS injector set (200) in a third combustor load range between a 35% combustor load and the 50% combustor load, and introducing the gaseous fuel (114A) into the tertiary combustion zone (204) for combustion, Between the 50% combustor load and the 100% combustor load, the supply of the gas fuel (114A) to the HE fuel nozzle set (182), the first AFS injector set (180), and the second AFS injector set (200) is interrupted. The combustor (100) according to claim 11, wherein the combustor (100) is operated in a first simultaneous firing operation mode including the following.

13. The controller (220) is For a first combustor load range from 0% combustor load to 50% combustor load, the steps include supplying fuel to the HE fuel nozzle set (182) and introducing the gaseous fuel (114A) into the primary combustion zone (188) for combustion, The steps include supplying fuel to the first AFS injector set (180) and introducing the gaseous fuel (114A) into the secondary combustion zone (194) for a second combustor load range from 10-20% combustor load to 50% combustor load, The steps include supplying fuel to the second AFS injector set (200) in a third combustor load range between a 35% combustor load and the 100% combustor load, and introducing the gaseous fuel (114A) into the tertiary combustion zone (204) for combustion, Between the 50% combustor load and the 100% combustor load, the supply of the gas fuel (114A) to the HE fuel nozzle set (182) and the first AFS injector set (180) is interrupted. The combustor (100) according to claim 11, wherein the combustor (100) is operated in a second simultaneous firing operation mode including the following.

14. The controller (220) is The first combustor load range from 0% combustor load to 100% combustor load includes the steps of supplying fuel to the HE fuel nozzle set (182), introducing the gaseous fuel (114A) into the primary combustion zone (188), and burning it, The steps include supplying fuel to the first AFS injector set (180) and introducing the gaseous fuel (114A) into the secondary combustion zone (194) for a second combustor load range from 10-20% combustor load to 50% combustor load, The steps include supplying fuel to the second AFS injector set (200) in a third combustor load range between a 35% combustor load and the 100% combustor load, and introducing the gaseous fuel (114A) into the tertiary combustion zone (204) for combustion, The steps include interrupting the supply of the gas fuel (114A) to the first AFS injector set (180) between the 50% combustor load and the 100% combustor load, and The combustor (100) according to claim 11, wherein the combustor (100) is operated in a third simultaneous firing operation mode including the following.

15. The controller (220) is The first combustor load range from 0% combustor load to 100% combustor load includes the steps of supplying fuel to the HE fuel nozzle set (182), introducing the gaseous fuel (114A) into the primary combustion zone (188), and burning it, The steps include supplying fuel to the first AFS injector set (180) and introducing the gaseous fuel (114A) into the secondary combustion zone (194) for a second combustor load range from 10-20% combustor load to 100% combustor load, The steps include supplying fuel to the second AFS injector set (200) and introducing the gaseous fuel (114A) into the tertiary combustion zone (204) for combustion in a third combustor load range between a 35% combustor load and the 100% combustor load, and The combustor (100) according to claim 11, wherein the combustor (100) is operated in a fourth simultaneous firing operation mode including the following.

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