NOZZLE AND FUEL SYSTEM FOR OPERATION WITH VARIABLE CALCIUM GAS

Abstract

Fuel nozzle assembly (350) for a gas turbine combustion chamber, the fuel nozzle assembly (350) comprising: a housing (351) with a first port (353) connected to a high-calorific fuel supply (316), a second port (355) separate from the first port (353) and connected to a first low-calorific gas supply (326), and a third port (357) separate from the first port (353) and the second port (355) and connected to a second low-calorific gas supply (328); a first gallery (352) in the housing (351) connected to the first port (353); a second gallery (354) in the housing (351) separate from the first gallery (352) and connected to the second port (355); a third gallery (356) in the housing (351).which is separated from the first (352) and the second (354) gallery and connected to the third port (357); a plurality of injection holes (368, 372, 376) arranged circumferentially in the housing (351), wherein the plurality of injection holes (368, 372, 376) comprises a first section (368) connected to the first gallery (352), a second section (372) connected to the second gallery (354), and a third section (376) connected to the third gallery (356), wherein the second section (372) and the third section (376) of the plurality of injection holes (368, 372, 376) are configured to inject gas from each of the respective second (354) and third (356) galleries into a tubular combustion chamber (10), and wherein the first section (368) of the A multitude of injection holes (368, 372, 376) are configured to inject high-calorific fuel (304) from the first gallery (352) into the tube combustion chamber (10),and wherein the first section of injection holes (368) each have a radial and a tangential angle which provide a radially outward turbulence for the high-calorific fuel (304) in the first gallery (352).

Description

priority claim

[0001] This application claims priority over US patent application number 16 / 505,343, filed on July 8, 2019, the entire contents of which are hereby incorporated into the present subject matter. Field of invention

[0002] The present invention relates to nozzles and fuel systems for operation with gas with varying calorific value, for example in operation with tube burners for gas turbines. General state of the art

[0003] Improvements are possible in the configuration of nozzle arrangements for use in tubular burners and in the control of air and air / gas mixture flows in tubular burners that use low-calorific-value gaseous fuels. These flows influence the completeness of combustion and thus the level of emissions and the thermal efficiency of the combustion chamber. Such improvements are described below. BRIEF SUMMARY OF THE INVENTION

[0004] According to one embodiment of the present disclosure, a fuel nozzle assembly is provided for a gas turbine combustion chamber. The fuel nozzle assembly can comprise a housing with a first port connected to a first low-calorific-value gas supply, a second port separate from the first port and connected to a second low-calorific-value gas supply, and a third port separate from the first and second ports and connected to a high-calorific-value gas supply.The fuel nozzle arrangement can further include a first gallery in the housing connected to the first opening, a second gallery in the housing separate from the first gallery and connected to the second opening, a third gallery in the housing separate from the first and second galleries and connected to the third port, and a plurality of injection holes arranged circumferentially in the housing, wherein the plurality of injection holes comprise a first section connected to the first gallery, a second section connected to the second gallery, and a third section connected to the third gallery, wherein the plurality of injection holes is configured to inject gas from each respective gallery into a tubular combustion chamber.

[0005] In some embodiments, the fuel nozzle assembly may include at least one insulating layer positioned between the first channel, the second channel, and the third channel. The fuel nozzle assembly may further include a fuel system that controls the first low-calorific-value gas supply, the second low-calorific-value gas supply, and the high-calorific-value supply. The fuel system may include a control valve connected to a low-calorific-value gas that controls the first and second low-calorific-value gas supplies, and a control valve connected to a high-calorific-value fuel that controls the high-calorific-value fuel supply. The fuel system may further include a shut-off valve connected to and controlling the first and / or second low-calorific-value gas supplies.The fuel system can automatically switch between supplying the first low-heat gas supply and the second low-heat gas supply to the housing, thereby controlling the use of the second and third channels. The fuel system can automatically switch between supplying one of the first and second low-heat gas supplies to the housing, or both the first and second low-heat gas supplies to the housing, thereby controlling the use of the second and third channels.

[0006] In some embodiments, the fuel system can be operated in a dual-fuel mode, in which it is operated with either the low-calorific gas or the high-calorific fuel. In some embodiments, the fuel system can be operated in a bi-fuel mode, in which it is operated with both the low-calorific gas and the high-calorific fuel. The third section of the injection holes can each have a radial and a tangential angle, providing radially outward turbulence for the high-calorific-value fuel in the third gallery. The first low-calorific-value gas supply, the second low-calorific-value gas supply, and the high-calorific-value fuel supply can be combined coaxially in the housing, and the gas turbulence of the first, second, and third galleries is separated from air turbulence by an air source.The first channel may include a liquid fuel nozzle, and the liquid fuel nozzle may include a liquid fuel atomizer.

[0007] According to embodiments of the present disclosure, a fuel nozzle assembly is provided for a gas turbine combustion chamber. The fuel nozzle assembly can further comprise a fuel system that controls the first low-calorific-value gas supply, the second low-calorific-value gas supply, and the high-calorific-value supply. The assembly can include a housing having a first port connected to the first low-calorific-value gas supply, a second port separate from the first port and connected to the second low-calorific-value gas supply, and a third port separate from the first and second ports and connected to the high-calorific-value fuel supply.The fuel nozzle assembly may also comprise a first gallery in the housing connected to the first port, a second gallery in the housing separate from the first gallery and connected to the second port, and a third gallery in the housing separate from the first and second galleries and connected to the third port. In some embodiments, the fuel nozzle assembly may comprise a plurality of injection ports arranged circumferentially in the housing, the plurality of injection ports comprising a first section connected to the first gallery, a second section connected to the second gallery, and a third section connected to the third gallery, the plurality of injection ports being configured to inject gas from each respective gallery into a tubular combustion chamber.The fuel system can automatically switch between providing one of the first low calorific value gas supplies and the second low calorific value gas supplies to the casing, and both the first and second low calorific value gas supplies to the casing, thereby controlling the use of the second and third channels.

[0008] In some embodiments, the fuel system also includes a shut-off valve connected to and controlling the first supply of low-calorific gas and / or the second supply of low-calorific gas. The fuel system can operate in a dual-fuel mode, where it uses either the low-calorific gas or the high-calorific fuel. Alternatively, the fuel system can operate in a bi-fuel mode, where it uses both the low-calorific gas and the high-calorific fuel simultaneously.

[0009] In some embodiments, the third section of the injection holes has both a radial and a tangential angle, which radially swirl the high-calorific fuel in the third gallery outwards. The first low-calorific gas supply, the second low-calorific gas supply, and the high-calorific fuel supply can be coaxially combined in the housing, and the gas swirl of the first, second, and third galleries is separated from air swirls by an air source. The third section of the injection holes can each have a radial and a tangential angle, which provide radially outward swirl for the high-calorific fuel in the third gallery. The first channel can include a liquid fuel nozzle.

[0010] The accompanying drawings, which form part of this description, illustrate an embodiment of the invention and, together with the description, serve to explain the principles of the invention. List of characters Fig. Figure 1 is a schematic representation of a gas turbine and a tube combustion chamber according to embodiments of this disclosure; Fig. Figure 2 is a schematic illustration of a fuel system according to an embodiment of this disclosure. Fig. 3. is a perspective cross-sectional view of a nozzle arrangement according to embodiments of this disclosure; and Fig. Figure 4 is a perspective cross-sectional view of a nozzle assembly according to the embodiments of this disclosure. DESCRIPTION OF THE EXECUTION FORM

[0011] The tubular combustion chamber of the present invention, which is generally designated by reference numeral 10 in the figures, is for use in the combustion of fuel with a low calorific value using compressed air from the compressor 6 and for supplying combustion gases to the gas turbine 8, e.g., for work-generating expansion as in a gas turbine engine. See Fig. 1. The compressor 6 may be a centrifugal compressor, and the gas turbine 8 may be a radially inlet turbine, but these are merely preferred and are not intended to limit the scope of protection of the present invention as defined by the appended claims and their equivalents. The disclosure of this embodiment with respect to the use of low-calorific-value fuel is not intended to be limiting. Aspects of the embodiment may also offer advantages when used with higher-calorific-value fuels.

[0012] According to the present invention, as it is implemented and generally described herein, the tube combustion chamber 10 can comprise a generally cylindrical housing with an interior, a longitudinal inlet, and an annular inlet for receiving compressed air at one longitudinal end, the axis being terminated at the other longitudinal end. As implemented herein and with reference to Fig. 1 includes the tube combustion chamber 10, an outer housing 12 with an inner 14, an annular inlet 18 configured to receive compressed air from the compressor 6.

[0013] According to the present invention, the combustion chamber can also comprise a generally cylindrical combustion chamber lining, which is arranged coaxially within the housing and is configured to define a generally annular passage with the housing for the compressed air received through the inlet. The lining also defines respective radially internal volumes for a combustion zone and a dilution zone. The dilution zone is axially located away from the closed housing end with respect to the combustion zone, and the combustion zone is axially adjacent to the closed housing end.

[0014] The interior 14 defines a combustion zone in which compressed air and fuel are burned to produce hot combustion gases. In conjunction with the fuel nozzle assembly 40, the combustion chamber 10 is configured to provide stable recirculation, which promotes primary combustion in a recirculation area of ​​the combustion zone in a manner known to those skilled in the art. The combustion zone may further include an intermediate area for secondary combustion. The combustion chamber 10 may also have a dilution zone in which combustion gases are mixed with dilution air from dilution ports to lower the temperature of the combustion gases before work-generating expansion takes place in the turbine 8.

[0015] Also according to the present invention, the combustion chamber comprises a fuel nozzle assembly 40, which is arranged at the closed housing end and configured to inject fuel into the combustion zone. The nozzle assembly 40 can also have a plurality of swirl vanes arranged circumferentially around the nozzle to cause a swirling flow pattern of the fuel / air mixture. Furthermore, the fuel nozzle assembly can be arranged coaxially with the lining. As with reference to the Fig. 1 and Fig. 2 The fuel system 300 of the nozzle assembly 40 can provide a fuel supply 316 with high calorific value, a first gas supply 326 with low calorific value and a second gas supply 328 with low calorific value.

[0016] Fig. Figure 1 is a schematic representation of a gas turbine and a tube burner. Fig. Figures 2-4 illustrate details of the schematic representation of Fig. 1. As with reference to the Fig. 3 and Fig. As described in 4, the in Fig. 1 nozzle assembly 40 shown by a fuel system 300 ( Fig. 2) and a nozzle arrangement 350 ( Fig. 3 and Fig. 4) are replaced, which can be interchangeable with the nozzle assembly 40, so that the fuel system 300 and the nozzle assembly 350 are connected to the can combustion chamber 10 in the same or a similar way as the nozzle assembly 40.

[0017] Fig. Figure 2 illustrates a schematic fuel system 300 for supplying low- and high-calorific-value fuel to the nozzle for operation with a gas of varying calorific value. The high-calorific fuel can also be a liquid fuel. The fuel system 300 can have two independent supplies, for example, a high-calorific fuel 304 and a low-calorific gas 308. The gas supplies of the high-calorific fuel 304 and the low-calorific gas 308 are not mixed to avoid condensation problems that can occur in cases where one of the gas supplies has a high dew point. In some embodiments, the high-calorific fuel 304 can have a constant or nearly constant calorific value. The high-calorific fuel 304 with a nearly constant calorific value can be controlled by a control valve 312, which selectively provides a high-calorific fuel supply 316 to the nozzle assembly 350.

[0018] The low-calorific-value gas 308 can have a variable calorific value, meaning its calorific value can fluctuate considerably. The low-calorific-value gas 308 can be controlled by a control valve 320. The control valve 320 can control the supply of the low-calorific-value gas 308 to one or more supply lines 322, 323, which can be connected to either one or two galleries of the nozzle assembly 350, as described below. The low-calorific-value gas 308 can be controlled by a shut-off valve 324 on at least one of the supply lines 322, 323. Accordingly, the nozzle assembly 350 can be provided with a first low-calorific-value gas supply 326 and a second low-calorific-value gas supply 328.

[0019] The fuel system 300 can be operated with two different gaseous fuels (e.g., high-calorific fuel 304 and low-calorific gas 308), either in a dual-fuel mode, in which the system 300 operates with one of the fuels, or in a bi-fuel mode, in which the system 300 operates with both fuels simultaneously. For example, in dual-fuel mode, the system 300 can supply high-calorific fuel 304 to the nozzle assembly 350 without supplying low-calorific gas 308 to the nozzle assembly 350. In another example, in bi-fuel operation, the system 300 can supply low-calorific gas 308 to the nozzle assembly 350 without supplying the nozzle assembly with high-calorific fuel 304. Additionally or alternatively, the system 300 can simultaneously supply high-calorific-value fuel 304 and low-calorific-value gas 308 to the nozzle arrangement 350 in bi-fuel mode.

[0020] As in Fig. As illustrated in Figure 3, the nozzle assembly 350 can have a housing 351 containing three galleries: a first gallery 352, a second gallery 354, and a third gallery 356. Each gallery can have an inlet and an outlet. The first channel 352 can have port 353, the second channel 354 can have port 355, and the third channel 356 can have port 357. The three galleries 352, 354, and 356 can be coaxially combined in the nozzle assembly 350. The high calorific value fuel supply 316 can be connected to the first channel 352 via the connection 353; the first channel 352 can be thermally insulated by an insulating layer 358 (e.g. by an air gap) to prevent heat transfer between the independent fuel supplies; the thermal insulation can prevent possible fuel condensation that may be caused by heat transfer between the fuel supplies.The second gallery 354 and the third gallery 356 can extend circumferentially around the first gallery 352 at radial distances from it. In some embodiments, the first gallery 352 can be positioned centrally within the housing 351, with the second gallery 354 and the third gallery positioned at radial distances from the center of the housing 351.

[0021] The nozzle arrangement 350 can include a second gallery 354 and a third gallery 356, which are connected via the connections 355 and 357 respectively to the low calorific value gas supplies 326, 328. Separate galleries (e.g., second gallery 354 and third gallery 356) can be implemented because the range of calorific values ​​for the low calorific value gas 308 can be wide (e.g., the nozzle covers the range from LHVm / 5 to LHVm, where LHVm is the maximum value for which the nozzle is designed (e.g., 5–25 MJ / m³)). In some embodiments, one of the second channel 354 and the third channel 356 can be used when there is a low gas flow into the nozzle assembly 350 (e.g., in the case of a high calorific value). In other embodiments, two galleries (e.g., both the second gallery 354 and the third gallery 356) are used in the case of a high gas flow (e.g., in the case of a low calorific value).

[0022] The housing 351 can include a plurality of injection holes on an outlet side 364 of the housing 351. A first group 368 of injection holes can be positioned on the outlet side 364 of the housing 351, and this first group 368 of injection holes can be connected to and aligned with the first channel 352. The first group 368 of injection holes can each include a radial and a tangential angle, which can provide radially outward swirling for the high-calorific fuel in the first gallery 352. The first channel 352 can be a radially outward swirling injection hole (e.g., a first group 368) that does not interfere with the recirculation backflow of the tube combustion chamber 10.

[0023] A second group 372 of injection holes can be positioned on the outlet side 364 of the housing 351, and this second group 372 of injection holes can be connected to and aligned with the second channel 354. A first group 368 of injection holes can be positioned on the outlet side 364 of the housing 351, and this first group 368 of injection holes can be connected to and aligned with the first channel 352. Each of the first group 368, the second group 372, and the third group 376 can be positioned in a circular pattern around the outlet side 364 of the housing 351, such that each group lies in a pattern aligned with each respective gallery to which the group is connected.The injection holes of the second group 372 and the third group 376 can each have a radial and a tangential angle, which can provide radially outward turbulence for the low-calorific-value gas in the second gallery 354 and the third gallery 356, respectively. The first channel 352 can be a radially outward turbulence injection hole (e.g., a first group 368) that does not interfere with the recirculation backflow of the tubular combustion chamber 10. The fuel through all three fuel channels (first channel 352, second channel 354, and third channel 356) can be injected at an angle so as not to negate the effect of independent air turbulence for flame stabilization in the tubular combustion chamber 10 discussed herein.

[0024] Fig.Figure 4 illustrates another embodiment of the nozzle assembly 350 in which the first channel 352 is replaced by a liquid fuel nozzle 400. The liquid fuel nozzle 400 can be connected to a liquid fuel supply. The liquid fuel nozzle 400 can have a liquid fuel atomizer 402 at its outlet side. The liquid fuel atomizer 402 can convert liquid from the liquid fuel supply into a collection of droplets. The housing 350 can have an injection hole 404 that can discharge the liquid fuel from the liquid fuel nozzle 400. Additionally, the liquid fuel nozzle 400 can have an air chamber 408 that surrounds the liquid fuel nozzle 400 and is positioned between the liquid fuel nozzle 400 and the insulating layer 358.

[0025] A control system can monitor relevant parameters in the gas fuel system 300, including the opening and closing of each control valve 312, 320, shut-off valve 324, and gas pressures and temperatures (e.g., pressures and temperatures of the high-calorific fuel 304, the low-calorific gas 308). Based on these parameters, the shut-off valve 324 can be operated for one of the low-calorific-value gas supplies 326, 328 to ensure a sufficient and controlled pressure drop across the nozzle assembly 350. The control sequence monitors relevant operating conditions and can automatically switch between using the second channel 354 and the third channel 356, and both channels (e.g., simultaneous use of the second channel 354 and the third channel 356) for low-calorific-value gas fuel injection.

[0026] As described above, the combustion chamber 10 can offer advantages when burning low-calorie fuel. Introducing compressed air into an intermediate area 38 of the combustion zone 32 can serve to facilitate complete combustion, i.e., to reduce or eliminate the amount of unburned fuel, as well as for emission control (e.g., of CO and NOx). It will be apparent to those skilled in the art that various modifications and variations can be made to the devices and methods of this disclosure without departing from the teachings contained herein. Although embodiments are apparent to those skilled in the art from considering this description and the practice of the disclosed device, the description and examples are to be regarded only as examples, the true scope of protection being specified by the following claims and their equivalents.

Claims

[1] Fuel nozzle arrangement for a gas turbine combustion chamber, the fuel nozzle arrangement comprising: a housing with a first connection connected to a first low calorific value gas supply, a second connection separate from the first connection and connected to a second low calorific value gas supply, and a third connection separate from the first and second connections and connected to a high calorific value fuel supply. a first gallery in the housing, which is connected to the first connection; a second gallery in the housing, which is separate from the first gallery and connected to the second port; a third gallery in the housing, which is separate from the first and second galleries and connected to the third connection; a plurality of injection holes arranged circumferentially in the housing, wherein the plurality of injection holes comprises a first section connected to the first gallery, a second section connected to the second gallery, and a third section connected to the third gallery, wherein the plurality of injection holes is configured to inject gas from each respective gallery into a tubular combustion chamber. [2] Fuel nozzle arrangement according to claim 1, further comprising: at least one insulating layer positioned between the first gallery, the second gallery and the third gallery. [3] Fuel nozzle arrangement according to claim 1, further comprising: a fuel system that controls the first low-calorific-value gas supply, the second low-calorific-value gas supply, and the high-calorific-value fuel supply, wherein the fuel system comprises the following: a control valve connected to a low calorific value gas that controls the first low calorific value gas supply and the second low calorific value gas supply; a control valve connected to a high-calorific fuel that controls the high-calorific fuel supply. [4] Fuel nozzle arrangement according to claim 3, wherein: The fuel system further includes a shut-off valve that is connected to and controls the first low calorific value gas supply and / or the second low calorific value gas supply. [5] Fuel nozzle arrangement according to claim 4, wherein: the fuel system automatically switches between providing the first low-heat gas supply and the second low-heat gas supply to the housing, thereby controlling the use of the second and third channels. [6] Fuel nozzle arrangement according to claim 4, wherein: the fuel system automatically switches between providing one of the first low calorific value gas supplies and the second low calorific value gas supplies to the casing, and both the first and second low calorific value gas supplies to the casing, thereby controlling the use of the second channel and the third channel. [7] Fuel nozzle arrangement according to claim 4, wherein: the fuel system can be operated in a dual-fuel mode, in which the fuel system is operated either with the low-calorific gas or the high-calorific fuel. [8] Fuel nozzle arrangement according to claim 4, wherein: the fuel system can be operated in a dual-fuel mode, in which the fuel system is operated either with the low-calorific gas or the high-calorific fuel. [9] Fuel nozzle arrangement according to claim 1, wherein: The third section of the injection holes can each have a radial and a tangential angle, providing a radially outward turbulence for the high calorific value fuel in the third gallery. [10] Fuel nozzle arrangement according to claim 1, wherein: The first low-calorific-value gas supply, the second low-calorific-value gas supply, and the high-calorific-value fuel supply can be combined coaxially in the housing, and the gas turbulence of the first, second, and third galleries is separated from air turbulences from an air source. [11] Fuel nozzle arrangement according to claim 1, wherein: The first gallery includes a liquid fuel nozzle. [12] Fuel nozzle arrangement according to claim 11, wherein: The liquid fuel nozzle includes a liquid fuel atomizer. [13] Fuel nozzle arrangement for a gas turbine combustion chamber, the fuel nozzle arrangement comprising: a fuel system that controls the first low-calorific-value gas supply, the second low-calorific-value gas supply, and the high-calorific-value supply; a housing with a first connection that is connected to a first low-calorific-value gas supply, a second connection that is separate from the first connection and is connected to a second low-calorific-value gas supply, and a third connection that is separate from the first and second connections and is connected to a high-calorific-value fuel supply; a first gallery in the housing, which is connected to the first connection; a second gallery in the housing, which is separate from the first gallery and connected to the second port; a third gallery in the housing, which is separate from the first and second galleries and connected to the third connection; a plurality of injection holes arranged circumferentially in the housing, wherein the plurality of injection holes comprises a first section connected to the first gallery, a second section connected to the second gallery, and a third section connected to the third gallery, wherein the plurality of injection holes is configured to inject gas from each respective gallery into a tubular combustion chamber; wherein the fuel system can automatically switch between providing one of the first low calorific value gas supplies and the second low calorific value gas supplies to the housing and both the first and second low calorific value gas supplies to the housing, thereby controlling the use of the second channel and the third channel. [14] Fuel nozzle arrangement according to claim 13, wherein: The fuel system further includes a shut-off valve that is connected to and controls the first low calorific value gas supply and / or the second low calorific value gas supply. [15] Fuel nozzle arrangement according to claim 13, wherein: the fuel system can be operated in a dual-fuel mode, in which the fuel system is operated either with the low-calorific gas or the high-calorific fuel. [16] Fuel nozzle arrangement according to claim 13, wherein: the fuel system can be operated in a dual-fuel mode, in which the fuel system is operated either with the low-calorific gas or the high-calorific fuel. [17] Fuel nozzle arrangement according to claim 13, wherein: The third section of the injection holes can each have a radial and a tangential angle, providing a radially outward turbulence for the high calorific value fuel in the third gallery. [18] Fuel nozzle arrangement according to claim 13, wherein: The first low-calorific-value gas supply, the second low-calorific-value gas supply, and the high-calorific-value fuel supply are combined coaxially in the housing, and the gas turbulence of the first, second, and third galleries is separated from air turbulences by an air source. [19] Fuel nozzle arrangement according to claim 13, wherein: The third section of the injection holes can each have a radial and a tangential angle, providing a radially outward turbulence for the high calorific value fuel in the third gallery. [20] Fuel nozzle arrangement according to claim 13, wherein: The first gallery includes a liquid fuel nozzle.