Low-emission nozzles, low-emission dual-fuel combustors and gas turbine generator sets

Abstract

This invention relates to a low-emission nozzle, a low-emission dual-fuel combustion chamber, and a gas turbine generator set. The invention addresses the problem of high-temperature carbon buildup in existing technologies. It integrates a dual-fuel low-emission nozzle design, combining liquid fuel diffusion combustion and gaseous fuel premixed combustion. When the gas turbine uses gaseous fuel, the gaseous fuel is injected through small orifices on the low-emission nozzle's cyclone separator for good mixing with air, reducing pollutant emissions through premixed combustion. When the gas turbine uses liquid fuel, the air-assisted atomization nozzle at the center of the low-emission nozzle solves the problem of poor liquid fuel atomization at low operating conditions. Furthermore, a low-emission dual-fuel control system is proposed to supply either gaseous or liquid fuel to the gas turbine, regulate fuel supply, and achieve smooth online switching between gas and liquid fuels without shutting down the turbine. This invention is used for power generation.

Description

Technical Field

[0001] This invention relates to a low-emission nozzle, a low-emission dual-fuel combustion chamber, and a fuel control system for a gas turbine generator set. It belongs to the field of thermal energy and power engineering. Background Technology

[0002] With the continuous advancement of my country's maritime strategy, the exploration and extraction of offshore crude oil have intensified, leading to a rapid increase in offshore crude oil production. During crude oil extraction, a large amount of associated gas is often produced. This associated gas is flammable, explosive, and difficult to store and transport. For safety reasons, it is often directly burned from the beginning of extraction, resulting in serious energy waste. The national maritime strategy urgently requires solutions to this problem. Dual-fuel gas turbines are a power equipment that can effectively solve this problem. They not only provide power for crude oil development but also utilize associated gas as gaseous fuel. Without shutting down the turbine, they can achieve seamless online switching between liquid fuel and associated gas, improving the gas turbine's adaptability to fuels, effectively utilizing associated gas, and addressing the diverse fuel needs under different conditions during crude oil development.

[0003] The dual-fuel combustor and dual-fuel control system are the most important core components of a dual-fuel gas turbine. With the increasing demand for high-power, low-emission dual-fuel gas turbines driven by maritime strategies, higher requirements are being placed on the design of the combustor. Furthermore, dual-fuel gas turbines use gaseous fuel with associated gas for 95% of their overhaul cycle, only requiring liquid fuel in occasional malfunctions or when the gaseous fuel supply is adjusted. Therefore, achieving low emissions when using gaseous fuel is extremely urgent.

[0004] To meet the low emission requirements of dual-fuel gas turbines using associated gas, the most common solution currently is nozzle water injection technology. This involves spraying water into the combustion chamber to reduce the temperature of the combustion zone, thereby reducing emissions of pollutants such as nitrogen oxides. However, this also increases the amount of auxiliary equipment and complicates the auxiliary systems, severely impacting the inherent advantages of gas turbines in terms of small size and light weight, thus limiting the application of dual-fuel gas turbines. In contrast, multi-stage lean premixing technology thoroughly mixes fuel and air, eliminating fuel-rich zones and ensuring a uniform temperature distribution at the combustion chamber outlet. Simultaneously, a low gas / air ratio keeps the combustion chamber outlet temperature below the rated value, eliminating high-temperature anomalies and achieving efficient and stable combustion. This effectively achieves low emissions while overcoming the aforementioned limitations. A low-emission combustion chamber invented using this method, as reported in publication number CN102393028B, has achieved excellent low-emission results.

[0005] The patent application, CN103486617B, entitled "An Invention Patent for a Dual-Fuel Low-Emission Combustion Burner for Gas Turbines," describes a dual-fuel system that uses both gaseous and liquid fuels, while employing lean premixing to reduce nitrogen oxide emissions. When the main burner is operating, a small amount of cooling air is introduced to cool and protect the secondary burner's end face. However, due to the poor cooling effect of this small amount of air, high-temperature carbon buildup occurs in the secondary burner. Summary of the Invention

[0006] The purpose of this invention is to solve the problem of high-temperature carbon buildup in the auxiliary burner of existing dual-fuel low-emission burners. Furthermore, it provides a low-emission nozzle, a low-emission dual-fuel combustion chamber, and a gas turbine generator set.

[0007] The technical solution of this invention is:

[0008] Option 1: A low-emission nozzle, comprising a first fuel gas path, a second fuel gas path, an atomizing air path, a liquid fuel path, a purge air path, and a nozzle body; the first fuel gas path, the second fuel gas path, the atomizing air path, and the liquid fuel path are installed on the nozzle body in an internal oil and external gas configuration with the oil and gas paths interleaved. The atomizing air path, the first fuel gas path, and the liquid fuel path ensure the unit enters idle operating conditions and share the first air cyclone separator of the first fuel gas path; the atomizing air path, the second fuel gas path, and the liquid fuel path ensure the unit enters fast operating conditions and share the second air cyclone separator of the second fuel gas path. The purge air path is installed on the fuel outlet side of the nozzle body, and the purge air path employs impact convection cooling, film cooling, and thermal insulation cooling to prevent carbon buildup at the nozzle nozzle.

[0009] Option 2: A low-emission dual-fuel combustor, comprising a combustor shell, a combustor inner shell and a flame tube, a front support shell, a rear support shell, a combustor outlet, a diffuser, a combustor inlet, a positioner, and a low-emission nozzle. The combustor shell is sealed to the front support shell and the rear support shell via front and rear annular flanges, respectively. The combustor inner shell is connected to the front support shell via a front annular flange and together with the combustor shell, forms a three-dimensional annular working space. The diffuser is connected to the rear of the combustor inner shell, with the end of the diffuser serving as the combustor inlet. The combustor outlet is located on the rear support shell. The flame tube is installed within the three-dimensional annular working space. The low-emission nozzle passes through the front annular conical mounting hole of the front support shell and is inserted into the insertion hole at the head of the flame tube. A main combustion port is located in the middle of the flame tube. Two positioners are connected to the head of the flame tube. The tail mounting seat of the flame tube is mounted on the rear support shell using a three-point support.

[0010] Option 3: A gas turbine generator set, comprising the aforementioned low-emission dual-fuel combustion chamber, low-emission dual-fuel control system, compressor, turbine, and generator, wherein the low-emission dual-fuel combustion chamber is connected to the low-emission nozzle loop system of the low-emission dual-fuel control system;

[0011] High-temperature, high-pressure air from the compressor enters the diffuser through the combustion chamber inlet, is decelerated and diffused, and then flows into the combustion chamber annular cavity. The air is then distributed to the low-emission nozzles and mixed with liquid or gaseous fuel to form a combustible mixture. The mixture is then burned efficiently and stably in the flame tube and discharged from the combustion chamber outlet, driving the turbine to output power to generate electricity.

[0012] The low-emission dual-fuel control system includes a liquid fuel system, a gas fuel system, a liquid fuel purging system, a gas fuel purging system, an auxiliary atomizing air system, and a low-emission nozzle loop system.

[0013] The low-emission nozzle loop system includes a liquid fuel loop, an auxiliary atomizing air loop, a gaseous fuel first loop, and a gaseous fuel second loop. The liquid fuel loop, the auxiliary atomizing air loop, the gaseous fuel first loop, and the gaseous fuel second loop are respectively connected to the liquid fuel inlet pipe, the auxiliary atomizing air inlet pipe, the gaseous fuel first inlet pipe, and the gaseous fuel second inlet pipe on the low-emission nozzle through branch pipes.

[0014] When burning liquid fuel:

[0015] At ignition and idle operating conditions and below: the liquid fuel system is engaged, the gas fuel system is not engaged, the liquid fuel purging system is not engaged, the gas fuel purging system is engaged, and the auxiliary atomizing air system is engaged.

[0016] At this point, the liquid fuel system enters the liquid fuel loop of the low emission nozzle loop system through the liquid fuel flow path, and then enters the liquid fuel path of the low emission nozzle.

[0017] The auxiliary atomizing air system enters the auxiliary atomizing air ring pipe through the auxiliary atomizing air flow path, and then enters the atomizing air path of the low emission nozzle for auxiliary atomization of liquid fuel;

[0018] The gaseous fuel purging system is divided into two flow paths: the first branch purging path and the second branch purging path, which clean and purge the gaseous fuel ring pipe and the internal channels of the low emission nozzle when not in operation.

[0019] When the engine is running at idle speed or above: the purge air source of the atomized air path is changed from the auxiliary atomized air system to the atomized air purge path of the liquid fuel path purge system. That is, the auxiliary atomized air source is supplied by the compressed air in the annular cavity space formed by the combustion chamber shell and the flame tube of the low-emission dual-fuel combustion chamber, while the rest of the system remains unchanged.

[0020] When burning gaseous fuel:

[0021] The liquid fuel system is shut down, the gas fuel system is activated, and the liquid fuel purging system is activated.

[0022] At or below the ignition and idle operating conditions:

[0023] Compressed air in the annular space of the low-emission dual-fuel combustion chamber enters the liquid fuel path of liquid fuel system A, the second branch of the gas fuel flow path of the gas fuel purging system, and the auxiliary atomizing air path of the auxiliary atomizing air system.

[0024] Gaseous fuel enters the low-emission nozzle loop system through the gaseous fuel system, and then enters the first gaseous fuel inlet pipe of the low-emission nozzle.

[0025] The liquid fuel purging system is in purging operation mode. The auxiliary atomizing air inlet pipe and the liquid fuel inlet pipe are both supplied with compressed air from the annular cavity space formed by the combustion chamber shell and the flame tube of the low-emission dual-fuel combustion chamber to purge and cool each channel.

[0026] At or above the slow speed condition:

[0027] When the gaseous fuel purging system is shut down, the gaseous fuel enters the first gaseous fuel loop and the second gaseous fuel loop of the low emission nozzle loop system simultaneously through the gaseous fuel system, and then enters the first fuel gas path and the second fuel gas path of the low emission nozzle respectively.

[0028] When switching between gaseous and liquid combustion, both the liquid fuel purging system and the gaseous fuel purging system are shut down, and both the liquid fuel system and the gaseous fuel system are put into operation.

[0029] Compared with the prior art, the present invention has the following advantages:

[0030] 1. The low-emission nozzle of the present invention adopts a purging air path, and the purging air path of the present invention prevents carbon buildup at the nozzle by using impact convection cooling, air film cooling and thermal insulation cooling, effectively reducing the temperature of the core working components and extending the service life of the low-emission nozzle.

[0031] 2. The low-emission dual-fuel combustor of this invention effectively combines multi-stage lean-burn premixed low-emission technology with a dual-fuel low-emission nozzle. When using gaseous fuel in the combustor, the gaseous fuel is injected through small holes on the cyclone separator of the low-emission nozzle to achieve good and uniform mixing with air, reducing pollutant emissions through premixed combustion. When using liquid fuel in the combustor, the air-assisted atomization nozzle at the center of the low-emission nozzle solves the atomization problem of liquid fuel under the same gas distribution structure. This allows the low-emission nozzle to meet the dual-fuel requirements while enabling the use of lean-burn premixed combustion technology to reduce emissions under gaseous fuel conditions. The purpose of this invention is to address gas turbine pollutant emissions. To facilitate the effective operation of the low-emission dual-fuel combustor proposed in this invention, a dual-fuel control system is also proposed. This system can supply gaseous or liquid fuel to the entire unit according to usage requirements, and can regulate the fuel supply. It can also achieve smooth online switching between gaseous and liquid fuels without shutting down the unit. Furthermore, to prevent high-temperature carbon buildup in the other fuel path while one fuel is operating, a purging system is designed into the dual-fuel control system. This invention ensures that the gas turbine can simultaneously burn both gaseous and liquid fuels, reducing emissions and achieving low-carbon, environmentally friendly, and efficient operation of the gas turbine.

[0032] 3. The gas turbine of the present invention uses liquid fuel. During startup and low-operation operation, auxiliary atomizing air is actively supplied to the liquid low-emission nozzle air path to improve ignition performance and combustion efficiency. Under high operating conditions, compressed air from the combustion chamber is used to force the air in the combustion chamber into the low-emission nozzle air path under pressure difference, which enhances the atomization of liquid fuel and further improves combustion efficiency. It can conveniently and effectively solve the problem of poor atomization effect under ignition and idle conditions under single liquid fuel path conditions, while meeting the dual-fuel use requirements.

[0033] 4. When operating with gaseous fuel, a two-stage lean-burn premixing method is used to improve the uniformity of gaseous fuel and air mixing. The air volume ratio of the first air cyclone separator 2-5 and the second air cyclone separator 2-9 is 1:7, which matches the fuel supplied by the first gaseous fuel branch B0-1 and the second gaseous fuel branch B0-2. This controls the equivalence ratio of the two combustion zones to be the same and within the low emission range of 2.5 to 4.5, thereby ensuring that the combustion zone temperature is within the low emission combustion temperature control range of 1700℃ to 1900℃. This achieves efficient and stable combustion, while keeping NOx emissions within the low emission range. In addition, a main combustion port is designed in the middle of the flame tube to provide air and fuel for further mixing, reduce the temperature of the main combustion zone, and enhance the emission reduction effect, ultimately meeting or exceeding the emission standards of GB13223-2011.

[0034] 5. When the gas turbine of this invention uses gaseous fuel, during startup and low-operation operation, only the first air cyclone separator 2-5 and the gaseous fuel first branch B0-1 supply assembly are used. During high-operation operation, the second air cyclone separator 2-9 and the gaseous fuel second branch B0-2 work together with the gaseous fuel first branch B0-1, ensuring sufficient mixing of gaseous fuel and air, resulting in lower pollutant emissions. Through the effective combination of good atomization of liquid fuel during both slow and high-operation conditions, and the overall design that also considers the low emission use of gaseous fuel, the gas turbine achieves efficient operation with multiple fuels under all operating conditions, maintaining the inherent advantages of small size and light weight, broadening the range of fuels that can be used in gas turbines, reducing nitrogen oxide emissions, and achieving efficient energy utilization.

[0035] 6. The low-emission dual-fuel control system of the present invention can supply gaseous fuel or liquid fuel to the whole machine according to the usage requirements and perform fuel regulation. It can also achieve smooth online switching of gaseous / liquid fuel without stopping the machine. At the same time, in order to prevent high-temperature carbon buildup in the other fuel path when one fuel is working, a purging system is designed in the fuel control system to prevent carbon buildup in the fuel path.

[0036] 7. This invention integrates the design of a dual-fuel low-emission nozzle, combining liquid fuel diffusion combustion and gaseous fuel premixed combustion. By combining additive manufacturing and machining, it solves the technical challenges of forming complex structural components and precision machining of core parts, enabling the dual-fuel low-emission nozzle to operate well under different gas turbine operating conditions. When the gas turbine uses gaseous fuel, the gaseous fuel is injected through small holes on the cyclone separator of the low-emission nozzle to achieve good mixing with air, reducing pollutant emissions through premixed combustion. When the gas turbine uses liquid fuel, the air-assisted atomization nozzle at its center decomposes the liquid fuel... This invention addresses the problem of poor liquid fuel atomization in gas turbines under low operating conditions. It meets the dual-fuel requirements of low-emission nozzles and enables the use of lean-burn premixed combustion technology under gaseous fuel conditions to reduce gas turbine pollutant emissions. A low-emission dual-fuel control system is also proposed. This system can supply gaseous or liquid fuel to the gas turbine according to usage requirements and regulate the fuel supply. It can also achieve smooth online switching between gaseous and liquid fuels without shutting down the turbine. Furthermore, to prevent high-temperature carbon buildup in the fuel path when one fuel is in operation, a purging system is designed into the fuel control system to prevent carbon buildup in the fuel path. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the structure of the gas turbine generator set of the present invention;

[0038] Figure 2 This is a schematic diagram of the internal structure of the low-emission nozzle of the present invention;

[0039] Figure 3 This is a front view of the low-emission nozzle of the present invention;

[0040] Figure 4 yes Figure 3 The right view;

[0041] Figure 5 yes Figure 3 The left view;

[0042] Figure 6 This is a schematic diagram of the sealing assembly. Detailed Implementation

[0043] Specific implementation method one: Combining Figures 1 to 6 This embodiment describes a low-emission nozzle, which includes a first fuel gas path, a second fuel gas path, an atomizing air path, a liquid fuel path, a purge air path, and a nozzle body. The first fuel gas path, the second fuel gas path, the atomizing air path, and the liquid fuel path are installed on the nozzle body in an alternating configuration of internal oil and external gas. The atomizing air path, the first fuel gas path, and the liquid fuel path ensure that the unit enters the idle operating condition and share the first air cyclone separator 2-5 of the first fuel gas path. The atomizing air path, the second fuel gas path, and the liquid fuel path ensure that the unit enters the fast operating condition and share the second air cyclone separator 2-9 of the second fuel gas path. The purge air path is installed on the fuel discharge side of the nozzle body, and the purge air path adopts impingement convection cooling, air film cooling, and thermal insulation cooling to prevent carbon buildup at the nozzle.

[0044] The nozzle in this embodiment is a low-emission dual-fuel low-emission nozzle, which integrates the two fuel paths in a design concept. The low-emission nozzle housing and cyclone separator are manufactured by additive manufacturing and formed as a single piece. The core components of the low-emission nozzle fuel path are independently manufactured by precision machining and are detachable. The combination of additive manufacturing and machining is used to ensure the effective forming of complex structural parts and the machining accuracy requirements of precision parts.

[0045] Specific Implementation Method Two: Combining Figure 2 This embodiment describes a nozzle body comprising a low-emission nozzle housing 5-1 and a combustion chamber cover plate 5-2, with the combustion chamber cover plate 5-2 mounted on the fuel inlet of the low-emission nozzle housing 5-1. This arrangement facilitates connection and cooperation with the flame tube of the combustion chamber to achieve ignition. Other components and connection methods are the same as in specific embodiment one.

[0046] Specific implementation method three: Combining Figure 2This embodiment describes a liquid fuel circuit comprising a liquid fuel cyclone separator 1-1, a screw plug 1-4, a sealing cap 1-17, a sealing assembly, a screw plug 1-14, a liquid fuel heat insulation pipe 1-13, a liquid fuel circuit inlet pipe 1-9, a liquid fuel circuit connection cap 1-10, a liquid fuel circuit connection cone pipe 1-11, and a liquid fuel filter assembly 1-12. The liquid fuel circuit connection cone pipe 1-11 is inserted into the combustion chamber cover plate 5-2, and the liquid fuel filter assembly 1-12 is installed on the liquid fuel circuit connection... Inside the cone tube 1-11, the liquid fuel inlet pipe 1-9 is installed on the liquid fuel connecting cone tube 1-11 via the liquid fuel connecting cap 1-10. The liquid fuel cyclone separator 1-1 and the screw plug 1-4 are coaxially installed inside the low emission nozzle housing 5-1. The sealing cap 1-17 seals the screw plug 1-4 through a sealing assembly. The screw plug 1-14 is screwed onto the sealing cap 1-17. Both ends of the liquid fuel heat insulation pipe 1-13 are connected to the liquid fuel cyclone separator 1-1 and the liquid fuel connecting cone tube 1-11, respectively. With this configuration, this embodiment features a liquid fuel heat insulation pipe 1-13 on the outside of the fuel line (referring to the liquid fuel line) to prevent carbon buildup in the pipeline. A purge air path to prevent carbon buildup is designed at the low emission nozzle nozzle, effectively preventing high-temperature carbon buildup at the fuel nozzle. The liquid fuel inlet pipe 1-9 is a heat-insulated inlet pipe; other components and connections are the same as in specific embodiments one or two.

[0047] Specific implementation method four: Combination Figure 6 This embodiment describes a sealing assembly comprising a ring 1-15, a sealing ring 1-16, and a steel ring 1-18. The sealing ring 1-16 is an annular sealing ring with a tapered stepped groove 1-16-1 on its upper part. The steel ring 1-18 is fitted into the sealing ring 1-16. The lower outer surface of the ring 1-15 is tapered and stepped. The ring 1-15 is inserted into the stepped groove 1-16-1 of the sealing ring 1-16, and the upper end face of the ring 1-15 is lower than the upper end face of the sealing ring 1-16.

[0048] With this configuration, the circular ring 1-15, sealing ring 1-16, and steel ring 1-18 in this embodiment are integrally formed. The upper part of the sealing ring wraps around the circular ring 1-15. When the sealing ring is located within the injection groove of the sealing cover 1-17 and the low-emission nozzle housing 5-1, it achieves a tighter connection. Furthermore, during long-term use, especially under high-temperature conditions, the sealing ring 1-16 and steel ring 1-18 may experience thermal expansion. The steel ring further enhances the sealing effect, preventing seal failure.

[0049] In addition, in this embodiment, the upper end face of the ring 1-15 is lower than the upper end face of the sealing ring 1-16. At this time, when the plug 1-14 is turned, there is a pressing force on the sealing assembly, and the gap between the plug 1-14 and the sealing cover 1-17 is sealed to prevent the sealing ring from failing or leaking oil, thereby ensuring the smooth operation of the low emission nozzle.

[0050] Other components and connection methods are the same as those in specific implementation methods one, two or three.

[0051] Specific Implementation Method Five: Combining Figure 2 This embodiment describes an atomizing air path comprising an atomizing air cyclone separator 1-2, a cap 1-3, an auxiliary atomizing air path inlet pipe 1-6, an auxiliary atomizing air path connecting cap 1-7, and an auxiliary atomizing air path cone pipe 1-8. The atomizing air cyclone separator 1-2 is fitted onto the liquid fuel cyclone separator 1-1 and the screw plug 1-4. The cap 1-3 is fitted onto the atomizing air cyclone separator 1-2 and located on one side of the liquid fuel cyclone separator 1-1. The auxiliary atomizing air path inlet pipe 1-6 is installed on the combustion chamber cover plate 5-2. The auxiliary atomizing air path inlet pipe 1-6 is connected to the auxiliary atomizing air path cone pipe 1-8 via the auxiliary atomizing air path connecting cap 1-7. The bottom of the auxiliary atomizing air path cone pipe 1-8 is connected to the atomizing air cyclone separator 1-2 via an auxiliary atomizing air channel 1-5. This atomizing air path effectively atomizes and sprays the oil in the liquid fuel path, promoting ignition. Other components and connection methods are the same as any one of the specific implementation methods one to four.

[0052] Specific Implementation Method Six: Combination Figure 2 This embodiment describes the first fuel gas path, which includes a first gaseous fuel inlet pipe 2-1, a first gaseous fuel connecting cap 2-2, a first gaseous fuel connecting cone pipe 2-3, an arc-shaped clamp 2-4, a first air cyclone separator 2-5, a premixed first-path clamping component 2-6, a first cup-shaped assembly 2-7, and a second cup-shaped assembly 2-8.

[0053] A first gaseous fuel connecting cone 2-3 is mounted on the combustion chamber cover 5-2. A first gaseous fuel inlet pipe 2-1 is mounted on the first gaseous fuel connecting cone 2-3 via a first gaseous fuel connecting cap 2-2. An arc-shaped clamp 2-4 is mounted on the fuel ejection side end of the low-emission nozzle housing 5-1. A first-path air cyclone separator 2-5 is mounted on the rear end of the arc-shaped clamp 2-4. A premixed first-path clamping member 2-6 is coaxially inserted into the tail of the first-path air cyclone separator 2-5. A first cup-shaped assembly 2-7 and a second cup-shaped assembly 2-8 are fitted onto the premixed first-path clamping member 2-6 from the inside out. The bottom of the first gaseous fuel connecting cone 2-3 is connected to the first-path air cyclone separator 2-5 via a first gas passage. This configuration facilitates gas combustion, provides convenience for the purging system, and prevents carbon buildup in the low-emission nozzle. Other components and connections are the same as in any of the specific embodiments one to five.

[0054] Specific implementation method seven: Combination Figure 2 This embodiment describes the second fuel gas path, which includes a second air cyclone separator 2-9, a second cyclone separator housing 2-10, a second gas fuel inlet pipe 3-1, a second gas fuel connecting cap 3-2, a second gas fuel connecting cone pipe 3-3, a cap 3-4, a collar 3-5, and a premixed second-path clamping component 3-6.

[0055] The second-path cyclone separator housing 2-10 is mounted on the first-path air cyclone separator 2-5 via a cover 3-4. The second-path air cyclone separator 2-9 is mounted on the second-path cyclone separator housing 2-10. The premixed second-path clamping member 3-6 is mounted on the second-path cyclone separator housing 2-10 via a collar 3-5. The second gaseous fuel connecting cone pipe 3-3 is mounted on the combustion chamber cover plate 5-2. The second gaseous fuel inlet pipe 3-1 is connected to the second gaseous fuel connecting cone pipe 3-3 via a second gaseous fuel connecting cap 3-2. The second gaseous fuel connecting cone pipe 3-3 and the second-path air cyclone separator 2-9 are connected via a second gas passage. This configuration facilitates gas combustion, provides convenience for the purging system, and prevents carbon buildup in low-emission nozzles. Other components and connections are the same as in any of the specific embodiments one to five.

[0056] Specific implementation method eight: Combination Figures 2 to 4 This embodiment describes a purge air path that includes an impingement convection cooling air path, a film cooling air path, and a thermal insulation cooling air path, wherein:

[0057] The impact convection cooling gas path is as follows: The second-path cyclone shell 2-10 is provided with multiple second-path anti-carbon-deposit cold-state purging holes 6-3. External cold air flows in from the multiple second-path anti-carbon-deposit cold-state purging holes 6-3 and flows in the internal cooling channel formed by the second-path cyclone shell 2-10, the premixed first-path clamping component 2-6 and the first cup-shaped component 2-7. Under the action of gas pressure difference, it impacts and cools the premixed first-path clamping component 2-6 through multiple rows of holes on the first cup-shaped component 2-7. The cold air of the external purging system is sprayed out into the combustion space through the first nozzle 6-4 and the second nozzle 6-5 of the second-path anti-carbon-deposit cold-state purging system to form a heat insulation protective gas film. Finally, the temperature of the premixed first-path clamping component 2-6 is reduced by a combination of impact convection cooling and gas film cooling.

[0058] The air film cooling air path is as follows: The first air cyclone 2-5 has multiple anti-carbon buildup cold state purging holes 6-1. The cold air from the external purging system enters from the multiple anti-carbon buildup cold state purging holes 6-1 and flows in the cooling channel inside the cap 1-3. Finally, it is sprayed out from the anti-carbon buildup cold state purging nozzle 6-2 into the combustion space to form a heat insulation protective air film and reduce the temperature of the cap 1-3.

[0059] The heat insulation and cooling air path is as follows: multiple three-way cooling and anti-carbon-deposit cold-state purging holes 6-6 are opened on the collar 3-5. The cold air of the external purging system enters the internal cooling channel formed by the second-way cyclone shell 2-10, collar 3-5 and premixed second-way pressing component 3-6 through the multiple three-way cooling and anti-carbon-deposit cold-state purging holes 6-6. Finally, it is sprayed out from the multiple holes on the premixed second-way pressing component 3-6 into the combustion space to form a heat insulation and protective gas film, thereby reducing the temperature of the premixed second-way pressing component 3-6.

[0060] The purge air path of this embodiment is provided with three air-cooling channels, namely the oil circuit anti-carbon deposit purge path (air film cooling air path), the premixed first pressure member 2-6 cooling purge (impact convection cooling air path), and the premixed second pressure member 3-6 cooling purge (heat insulation cooling air path).

[0061] A stream of cooling air flows into the low-emission nozzle from the anti-carbon-deposit cold purge hole 6-1 and flows through the cooling channel inside the cap 1-3. Finally, it is sprayed out into the combustion space from the anti-carbon-deposit cold purge nozzle 6-2, forming a heat-insulating protective air mold, reducing the temperature of the cap 1-3, and preventing carbon deposits from forming.

[0062] Another stream of cooling air flows into the low-emission nozzle from the cooling purge path 6-3 and flows in the internal cooling channel formed by the second cyclone shell 2-10, the premixed first-path clamping component 2-6, and the first cup-shaped assembly 2-7. Under the action of pressure difference, it impacts and cools the premixed first-path clamping component 2-6 through the multiple rows of holes on the first cup-shaped assembly 2-7. Finally, it is sprayed out into the combustion space from the second anti-carbon-deposit cold purge nozzle 6-4 and the second anti-carbon-deposit cold purge nozzle 6-5 to form a heat-insulating protective gas mold. By combining the two methods of impact convection cooling and gas film cooling, the temperature of the premixed first-path clamping component 2-6 is reduced, and the premixed first-path clamping component 2-6 is protected.

[0063] The third stream of cooling air flows into the low-emission nozzle from the three-way cooling and anti-carbon-deposit cold-state purge holes 6-6, and flows within the cooling channel formed by the second-way cyclone housing 2-10, the collar 3-5, and the premixed second-way clamping component 3-6. Finally, it is ejected into the combustion space through multiple small holes on the premixed second-way clamping component 3-6, forming a heat-insulating protective air mold and reducing the temperature of the premixed second-way clamping component 3-6. Other components and connection methods are the same as in any one of the specific embodiments one to seven.

[0064] Specific Implementation Method Nine: Combining Figure 4 In this embodiment, the two-way anti-carbon buildup cold purge nozzle 6-4 and the two-way anti-carbon buildup cold purge nozzle 6-5 are both arranged in a ring array on the premixed first-way clamping member 2-6. This arrangement facilitates the formation of a ring-shaped gas film for cooling. Other components and connection methods are the same as any one of the specific embodiments in Specific Embodiment 18.

[0065] Specific Implementation Method Ten: Combining Figure 4 In this embodiment, the dual-path anti-carbon buildup cold purging nozzle 6-4 is an elliptical nozzle, and multiple dual-path anti-carbon buildup cold purging nozzles 6-4 are arranged in a clockwise inclined ring array. This arrangement facilitates the formation of an annular air film with a swirling angle. This air film is more robust, and the swirling area of ​​the airflow in contact with the outside environment per unit length is large, resulting in a better cooling effect. Other components and connection methods are the same as any one of embodiments one to nine.

[0066] Detailed Implementation Method Eleven: Combining Figure 4 In this embodiment, the two anti-carbon buildup cold purging nozzles 6-5 are rectangular nozzles. This design allows the directly ejected cold air to quickly cool the corresponding components. Other components and connections are the same as in any of the specific embodiments one through ten.

[0067] The low-emission nozzle of this invention is an integral structure, which mainly includes a first fuel gas path, a second fuel gas path, an atomizing air path, a liquid fuel path, and a purging air path to prevent carbon buildup.

[0068] The two fuel circuits (referring to the liquid fuel circuit and the fuel gas circuit) adopt an integrated design concept. The low-emission nozzle housing and cyclone separator are manufactured by additive manufacturing and formed as a whole. The core components of the low-emission nozzle oil circuit are independently processed by precision machining and the core components are detachable. The combination of additive manufacturing and machining is used to ensure the effective forming of complex structural parts and the machining accuracy requirements of precision parts. The entire low-emission nozzle has two gaseous fuel paths (referring to fuel gas paths), one liquid fuel path, and one atomizing air path. The inner side is the liquid fuel path, and the outer side is the gaseous fuel path, with the liquid and gaseous fuel paths arranged alternately. The atomizing air path, liquid fuel path, and first fuel gas path ensure that the gas turbine generator set (hereinafter referred to as the unit) enters the idle condition, and the liquid fuel path and the first fuel gas path share the first air cyclone separator 2-5. The atomizing air path, liquid fuel path, and second fuel gas path ensure that the unit enters the maximum operating condition, and the liquid fuel path and the second fuel gas path share the second air cyclone separator 2-9. A liquid fuel heat insulation pipe is designed on the upstream outer side of the liquid fuel path to prevent carbon buildup in the pipe. A purge air path to prevent carbon buildup is designed at the low-emission nozzle nozzle to effectively prevent high-temperature carbon buildup at the liquid fuel nozzle. The first and second fuel gas paths are equipped with gaseous fuel channels, which connect to a cap. The cap has evenly distributed air outlets on its end face. The cap is located inside a radial air cyclone separator. An annular cavity surrounds the cap on the cyclone separator. A fuel inlet channel communicating with the annular cavity is provided on the housing, and a fuel outlet channel communicating with the annular cavity is provided on the cyclone separator. The liquid fuel cyclone atomizing assembly includes a liquid fuel channel, a liquid fuel cyclone separator, a liquid fuel nozzle, and a carbon-preventing air cooling device. The liquid fuel auxiliary atomizing assembly includes an auxiliary atomizing air channel, an auxiliary atomizing air cyclone separator, and an auxiliary atomizing air nozzle. The liquid fuel cyclone separator is nested within the inner cavity of the atomizing air cyclone separator in a plug-in manner. Both are fixed to the low-emission nozzle housing by a detachable clamping and fixing assembly at a rated torque. The detachable clamping and fixing assembly is connected to the low-emission nozzle housing by a threaded connection using a cover, gasket, and plug, facilitating the repair, cleaning, and replacement of core working components, shortening the low-emission nozzle development cycle, and extending the low-emission nozzle's service life. The liquid fuel nozzle anti-carbon deposit air-cooling component draws air from the front normal air inlet of the first air cyclone separator 2-5 to the outer ring of the central liquid fuel nozzle to form an air-cooling channel, effectively reducing the temperature of the core working component; the clamping part anti-carbon deposit air-cooling component draws air from the oblique hole air inlet between the first air cyclone separator 2-5 and the second air cyclone separator 2-9 to the edge of the clamping part outlet and sprays it out in two directions, reducing the temperature of the clamping part through impact cooling and air film cooling.

[0069] Detailed Implementation Method Twelve: Combining Figure 1This embodiment describes a low-emission dual-fuel combustor, which includes a combustor outer shell 8-1, a combustor inner shell 8-2, and a flame tube 8-3. It also includes a front support shell 8-4, a rear support shell 8-5, a combustor outlet 8-5A, a diffuser 8-6, a combustor inlet 8-6A, a positioner 8-7, and a low-emission nozzle. The combustor outer shell 8-1 is sealed to the front support shell 8-4 and the rear support shell 8-5 via front and rear annular flanges, respectively. The combustor inner shell 8-2 is connected to the front support shell 8-4 via a front annular flange and together with the combustor outer shell 8-1, forms a three-dimensional combustion chamber. The combustion chamber annular cavity 8A has a diffuser 8-6 connected to the rear of the combustion chamber inner shell 8-2. The end of the diffuser 8-6 is the combustion chamber inlet 8-6A, and the combustion chamber outlet 8-5A is opened on the rear support shell 8-5. The flame tube 8-3 is installed in the three-dimensional annular working space. The low emission nozzle passes through the front annular conical surface mounting hole of the front bearing shell 8-4 and is inserted into the insertion hole at the head of the flame tube 8-3. The flame tube 8-3 has a main combustion hole 8-3A in the middle. The head of the flame tube 8-3 is connected to two positioners 8-7. The tail mounting seat of the flame tube 8-3 is installed on the rear support shell 8-5 with three-point support.

[0070] The low-emission nozzle is inserted into the head insertion hole of the flame tube through the mounting hole on the front annular conical surface of the front support housing, and is fixed and sealed by the low-emission nozzle mounting flange. The main combustion port is provided in the middle of the flame tube, and is fixed by three points of support through two positioners at the head and one mounting seat at the tail. The outer shell of the combustion chamber is connected to the front support housing and the rear support housing through the front and rear annular flanges respectively to ensure sealing. The inner shell of the combustion chamber is connected to the front support housing through the front annular flange, and together with the outer shell of the combustion chamber, they form a three-dimensional annular working space. The diffuser is connected to the rear of the inner shell of the combustion chamber. The rear support housing of the combustion chamber is used to provide the mounting seat for the flame tube and the combustion chamber outlet.

[0071] Other components and connection methods are the same as any one of the specific implementation methods one to eleven.

[0072] Detailed Implementation Method Thirteen: Combining Figures 1 to 6 This embodiment describes a low-emission nozzle as described in any one of embodiments 1 to 11. Other components and connection methods are the same as in any one of embodiments 1 to 12.

[0073] Specific Implementation Method Fourteen: Combining Figures 1 to 6 This embodiment describes a gas turbine generator set, which includes a low-emission dual-fuel combustion chamber 8, a low-emission dual-fuel control system, a compressor 7, a turbine 9, and a generator 10 as described in embodiments 12-13. The low-emission dual-fuel combustion chamber 8 is connected to the low-emission nozzle ring system F of the low-emission dual-fuel control system.

[0074] High-temperature and high-pressure air from compressor 7 enters diffuser 8-6 through combustion chamber inlet 8-6A, is decelerated and diffused, and then flows into combustion chamber annular cavity 8A. The air is then distributed to low emission nozzle 11 and mixed with liquid or gaseous fuel to form a combustible mixture. The mixture is then burned efficiently and stably in flame tube 8-3 and discharged from combustion chamber outlet 8-5A, driving turbine 9 to output power to generate electricity in generator 10.

[0075] The low-emission dual-fuel control system includes a liquid fuel system A, a gaseous fuel system B, a liquid fuel purging system C, a gaseous fuel purging system D, an auxiliary atomizing air system E, and a low-emission nozzle loop system F.

[0076] The low-emission nozzle loop system F includes a liquid fuel loop 1-9H, an auxiliary atomizing air loop 4-1H, a gas fuel first loop 2-1H, and a gas fuel second loop 3-1H. The liquid fuel loop 1-9H, the auxiliary atomizing air loop 4-1H, the gas fuel first loop 2-1H, and the gas fuel second loop 3-1H are respectively connected to the liquid fuel inlet pipe 1-9, the auxiliary atomizing air inlet pipe 1-6, the gas fuel first inlet pipe 2-1, and the gas fuel second inlet pipe 3-1 on the low-emission nozzle through branch pipes.

[0077] When burning liquid fuel:

[0078] When operating below ignition and idle conditions: Liquid fuel system A is engaged, gaseous fuel system B is not engaged, liquid fuel purging system C is not engaged, gaseous fuel purging system D is engaged, and auxiliary atomizing air system E is engaged.

[0079] At this time, the liquid fuel system A enters the liquid fuel ring pipe 1-9H of the low emission nozzle ring pipe system F through the liquid fuel flow path A0, and then enters the liquid fuel path of the low emission nozzle.

[0080] The auxiliary atomizing air system E enters the auxiliary atomizing air ring pipe 4-1H through the auxiliary atomizing air flow path E0, and then enters the atomizing air path of the low emission nozzle for auxiliary atomization of liquid fuel;

[0081] The gaseous fuel purging system D is divided into two flow paths, namely the first branch purging path D0-1 and the second branch purging path D0-2, which clean and purge the gaseous fuel ring pipe and the internal channels of the low emission nozzle when not in operation.

[0082] When the engine is running at idle speed or above: the purge air source of the atomized air path is changed from the auxiliary atomized air system E to the atomized air purge path C0-2 of the liquid fuel path purge system C. That is, the auxiliary atomized air source is supplied by the compressed air in the annular cavity space formed by the combustion chamber shell and the flame tube of the low emission dual fuel combustion chamber, and the rest of the system remains unchanged.

[0083] When burning gaseous fuel:

[0084] Liquid fuel system A is shut down, gaseous fuel system B is put into operation, and liquid fuel purging system C is put into operation.

[0085] At or below the ignition and idle operating conditions:

[0086] Compressed air in the annular space of the low-emission dual-fuel combustion chamber enters the liquid fuel path A0 of the liquid fuel system A, the second branch of the gas fuel flow path D0-2 of the gas fuel purging system D, and the auxiliary atomizing air path E0 of the auxiliary atomizing air system E.

[0087] Gaseous fuel enters the gaseous fuel loop 2-1H of the low emission nozzle loop system F through the gaseous fuel system B, and then enters the first gaseous fuel inlet pipe 2-1 of the low emission nozzle;

[0088] The liquid fuel purging system C is in purging operation. The auxiliary atomizing air inlet pipe 1-6 and the liquid fuel inlet pipe 1-9 are both supplied with compressed air from the annular cavity space formed by the combustion chamber shell and the flame tube of the low-emission dual-fuel combustion chamber to purge and cool each channel.

[0089] At or above the slow speed condition:

[0090] When the gaseous fuel purging system D is closed, the gaseous fuel enters the gaseous fuel first loop 2-1H and gaseous fuel second loop 3-1H of the low emission nozzle loop system F through the gaseous fuel system B, and then enters the first fuel gas path and the second fuel gas path of the low emission nozzle respectively.

[0091] When switching between gaseous and liquid combustion, both liquid fuel purging system C and gaseous fuel purging system D are shut down, while both liquid fuel system A and gaseous fuel system B are put into operation.

[0092] This combustion chamber and fuel control system enables the gas turbine to achieve low pollutant emissions when using gaseous fuel during high-operation-condition operation, and can also perform online stable switching between gaseous and liquid fuels without shutting down the turbine; it can meet the goals of stable dual-fuel combustion, smooth online switching, and reduced pollutant emissions in gas turbines.

[0093] Other components and connection methods are the same as any one of the specific implementation methods one to thirteen.

[0094] Low-emission dual-fuel control system: When the combustion gas is used, below idle speed, the liquid fuel system A is engaged, the gas fuel system B is not engaged, the liquid fuel purging system C is not engaged, the gas fuel purging system D is engaged, and the auxiliary atomizing air system E is engaged. At this time, the liquid fuel enters the liquid fuel ring pipe of the low-emission nozzle ring pipe system F, and then enters the liquid fuel path of the low-emission dual-fuel low-emission nozzle. The auxiliary atomizing air and the combustion chamber bleed air enter the auxiliary atomizing air ring pipe of the low-emission nozzle ring pipe system F, and then enter the atomizing air path of the low-emission dual-fuel low-emission nozzle for liquid fuel auxiliary atomization. The combustion chamber bleed air enters the first fuel gas path and the second fuel gas path, and then enters the gas fuel passage of the low-emission nozzle for purging.

[0095] When the engine is running at idle speed or above, the purging of the auxiliary atomizing air flow path is changed from the auxiliary atomizing air system E to the atomizing air purging flow path of the liquid fuel path purging system C, that is, all of them are switched to the combustion chamber annular compressed air, while the rest of the system remains unchanged.

[0096] When burning gaseous fuel, liquid fuel system A is closed, gaseous fuel system B is engaged, and liquid fuel purging system C is engaged. Below idle speed, compressed air from the combustion chamber annular cavity enters the liquid fuel path of liquid fuel system A, the second branch purging path D0-2 of the gaseous fuel flow path of gaseous fuel purging system D, and the auxiliary atomizing air path of auxiliary atomizing air system E. Gaseous fuel enters the first gaseous fuel annular loop 2-1H of the low-emission nozzle annular system F through gaseous fuel system B, and then enters the first fuel gas path of the low-emission nozzle. Compressed air from the combustion chamber annular cavity enters the second branch gaseous fuel path B0-2, and then enters the second fuel gas path of the low-emission nozzle for purging. Above idle speed, gaseous fuel purging system D is closed, and gaseous fuel simultaneously enters the first gaseous fuel annular loop 2-1H and the second gaseous fuel annular loop 3-1H of the low-emission nozzle annular system F through gaseous fuel system B, and then enters the first and second fuel gas paths of the low-emission nozzle, respectively.

[0097] During fuel switching combustion: Liquid fuel purging system C and gaseous fuel purging system D are not operating, while liquid fuel system A and gaseous fuel system B are both operational. When switching from gaseous fuel to liquid fuel, the opening of the regulating valve in gaseous fuel system B gradually decreases, resulting in a gradual decrease in gaseous fuel flow; conversely, the opening of the regulating valve in liquid fuel system A gradually increases, resulting in a gradual increase in liquid fuel flow. The rate of increase / decrease in both systems is matched according to the calorific value, ensuring that the increase in liquid fuel... The product of the rate of decrease and its calorific value should be equal to the product of the rate of decrease and its calorific value for gaseous fuel, or the product of the rate of decrease and its calorific value for liquid fuel and the product of the rate of increase and its calorific value for gaseous fuel. When switching fuels, the rate of increase and decrease of both should be strictly controlled to achieve the shortest switching time (switching time refers to the time required to completely switch from the current working fuel to another fuel when the switching command is given and the timing starts) and the most stable unit power fluctuation (unit power fluctuation refers to the ratio of the difference between the maximum and minimum power of the unit during the switching process to the power of the unit during stable operation. To ensure the stable operation of the power grid, the unit power fluctuation range is generally required to be no more than 10%).

[0098] Regarding liquid fuel supply and air-assisted atomization: When burning liquid fuel, from startup to idle, the auxiliary atomizing air system E is activated to assist in liquid fuel atomization. The auxiliary atomizing air system E is equipped with a throttling orifice plate, which can be used to adjust the pressure and flow rate of the auxiliary atomizing air during operation. This prevents the liquid fuel atomization effect from deteriorating due to excessively high or low auxiliary atomizing air pressure, resulting in incomplete combustion of the liquid fuel and thus causing the unit to experience thermal suspension (thermal suspension generally refers to the phenomenon that, during the startup of a gas turbine, no matter how much fuel is added, the unit speed cannot be increased normally). Above idle conditions, the atomizing air purging circuit of the liquid fuel purging system is activated, adjusting the auxiliary atomizing air to compressed air from the combustion chamber annulus, further improving the atomization effect of the liquid fuel above idle conditions.

[0099] When burning liquid fuel, from startup to idle, the auxiliary atomizing air system E is activated to assist in atomizing the liquid fuel. Above idle, the auxiliary atomizing air switches to compressed air from the combustion chamber annulus, further improving the atomization effect of the liquid fuel above idle. When burning gaseous fuel, combustion chamber bleed air is used to purge the fuel circuit. From startup to idle, only the first gaseous fuel branch (referring to the first gaseous fuel branch B0-1) is working. Above idle, the second gaseous fuel branch (referring to the second gaseous fuel branch B0-2) stops purging and is put into operation with gaseous fuel. As the operating condition increases, the fuel quantity in both the first and second gaseous fuel branches increases simultaneously. At a certain intermediate operating condition, the fuel quantity in the first gaseous fuel branch begins to decrease, while the fuel quantity in the second gaseous fuel branch continues to increase until the rated operating condition, at which point the equivalence ratio α of the combustion zones corresponding to the two fuel circuits is the same.

[0100] When burning gaseous fuel, during startup to idle condition, the fuel quantity is correlated with the exponential function of the high-pressure speed of the gas turbine, and the opening of the fuel regulating valve of the first branch of the gas fuel is controlled in real time by the equivalence ratio to ensure combustion stability and prevent flameout during startup.

[0101] When burning liquid fuel, at idle speed, the auxiliary atomizing air system E is equipped with a throttle orifice plate to regulate the pressure and flow of the auxiliary atomizing air. This prevents the fuel atomization effect from deteriorating due to excessively high or low auxiliary atomizing air pressure, resulting in incomplete fuel combustion and thus causing the unit to experience thermal suspension.

[0102] The combustion zone equivalence ratio α achieves low emissions within the range of 2.5≤α≤4.5, ensuring that the combustion zone temperature is within the low-emission combustion temperature control range, ultimately meeting or exceeding the emission standards of GB13223-2011.

[0103] Regarding gaseous fuel regulation: When burning gaseous fuel, combustion chamber bleed air is used to purge the liquid fuel path. From startup to idle, only the first gas fuel path is operational, and the fuel quantity is correlated with the high-pressure speed of the gas turbine. The opening of the first gas fuel regulating valve is controlled in real time through the equivalence ratio to ensure combustion stability and prevent combustion chamber flameout during startup. Above the idle operating condition, the second gas fuel path stops purging and gas fuel is simultaneously introduced. As the operating condition further increases, the fuel quantity in both the first and second gas fuel paths increases simultaneously. At a certain intermediate operating condition (which is generally selected based on the characteristics of the gas turbine), the fuel quantity in the first gas fuel path begins to decrease, while the fuel quantity in the second gas fuel path continues to increase until the rated operating condition, at which point the equivalence ratio of the combustion zones corresponding to the two gas paths is basically the same, thereby enabling the gas turbine to achieve the lowest pollutant emission target.

[0104] The flame tube of this embodiment is equipped with main combustion holes, located in the middle of the tube body, with a total of 8 holes, symmetrically distributed along the mid-section. On the one hand, it provides supplemental air to mix with fuel, reduces the temperature of the main combustion zone, and enhances the emission reduction effect. On the other hand, it adjusts the uniformity of the temperature distribution at the combustion chamber outlet and extends the overall overhaul period of the unit.

[0105] Both the liquid fuel system and the gaseous fuel system in this embodiment are equipped with filters to ensure fuel cleanliness. The liquid fuel swirl atomizing assembly is equipped with an inlet filter assembly, which can effectively remove impurities in the incoming medium, improve the reliability and service life of the low-emission nozzle, and is fixed by a detachable stop ring for easy replacement and cleaning.

[0106] In this embodiment, both the first and second gas fuel supply components are equipped with throttling components, which can be used to precisely adjust the gas fuel flow rate, thereby ensuring the consistency of the flow rate of multiple low-emission nozzles during the overall assembly of the gas turbine.

[0107] The dual-fuel control system of this embodiment is equipped with a gaseous fuel vent valve and a liquid fuel discharge valve to drain unused gaseous fuel and waste liquid fuel from the pipeline, ensuring the safe operation of the unit.

[0108] The dual-fuel control system pipeline in this embodiment is equipped with a one-way check valve to prevent fuel from flowing back to the upstream pipeline due to sudden high pressure downstream, thus ensuring the safety of the fuel system and unit operation.

[0109] The dual-fuel control system of this embodiment is equipped with a water bath heater for gaseous fuel to prevent the fuel temperature from dropping suddenly due to pressure reduction, causing the fuel to reach the dew point temperature and causing the pipelines and valves to freeze, thereby ensuring the stability of the fuel system operation.

[0110] The dual-fuel control system of this embodiment has a total of 8 flow paths (the 8 flow paths are: liquid fuel path, gas fuel path branch 1 and gas fuel path branch 2 of the gas fuel system, liquid fuel purging path and auxiliary atomizing air purging path of the liquid fuel purging system, auxiliary atomizing air path of the auxiliary atomizing air system, and gas fuel path branch 1 and gas fuel path branch purging path of the gas fuel purging system), all of which are optionally equipped with flow sensors to effectively monitor the actual flow rate of the medium, facilitate the control of the opening degree of the corresponding regulating valve, and thus ensure the stable operation of the gas turbine generator set.

[0111] The liquid fuels in this embodiment include, but are not limited to, light diesel oil, and the gaseous fuels include, but are not limited to, natural gas.

[0112] Specific Implementation Method Fifteen: Combining Figure 1This embodiment describes a liquid fuel system A comprising a liquid fuel source A1, a liquid fuel pipeline A0, a pump A2, a first filter A3, a first regulating valve A4, a first shut-off valve A5, a first flow sensor A6, a vent valve A7, and a first check valve A8. One end of the liquid fuel pipeline A0 is connected to the liquid fuel source A1, and the other end of the liquid fuel pipeline A0 is connected in series with the pump A2, the first filter A3, the first regulating valve A4, the first shut-off valve A5, the first flow sensor A6, and the first check valve A8, and then connected to the liquid fuel loop 1-9H. The vent valve A7 is connected in parallel on the liquid fuel pipeline A0 between the first flow sensor A6 and the first check valve A8.

[0113] This configuration facilitates the supply of liquid fuel to the combustion chamber and also allows for easy switching between liquid and gaseous fuels. Other components and connections are the same as in any of the specific embodiments one through fourteen.

[0114] Specific implementation method sixteen: Combination Figure 1 This embodiment describes a gaseous fuel system B, which includes a gaseous fuel source B1, a gaseous fuel path B0, a water bath heater B2, a second filter B3, a second shut-off valve B5, a vent valve B7, a second regulating valve B4-1, a third regulating valve B4-2, a third shut-off valve B5-1, a fourth shut-off valve B5-2, a second flow sensor B6-1, a third flow sensor B6-2, a second check valve B8-1, and a third check valve B8-2.

[0115] One end of the gaseous fuel path B0 is connected to the gaseous fuel source B1. The other end of the gaseous fuel path B0 is connected in series with a water bath heater B2, a second filter B3, and a second shut-off valve B5, and then splits into a first gaseous fuel branch B0-1 and a second gaseous fuel branch B0-2. The first gaseous fuel branch B0-1 is connected in series with a second regulating valve B4-1, a third shut-off valve B5-1, a second flow sensor B6-1, and a second check valve B8-1, and then connects to a first gaseous fuel loop 2-1H. The second gaseous fuel branch B0-2 is connected in series with a third regulating valve B4-2, a fourth shut-off valve B5-2, a third flow sensor B6-2, and a third check valve B8-2, and then connects to a second gaseous fuel loop 3-1H. This facilitates the supply of gaseous fuel to the combustion chamber and also facilitates the switching between liquid and gaseous fuels. Other components and connections are the same as in any of the specific embodiments one to fifteen.

[0116] Detailed Implementation Method Seventeen: Combining Figure 1 This embodiment describes an auxiliary atomizing air system E, which includes a compressed air source E1, an auxiliary atomizing air path E0, a throttling orifice plate E2, a fifth shut-off valve E5, an eighth flow sensor E6, and an eighth check valve E8.

[0117] One end of the auxiliary atomizing air path E0 is connected to the compressed air source E1, and the other end of the auxiliary atomizing air path E0 is connected in sequence to the orifice plate E2, the fifth shut-off valve E5, the eighth flow sensor E6, and the eighth check valve E8 before being connected to the auxiliary atomizing air ring pipe 4-1H. This configuration facilitates atomization of the liquid fuel and ensures combustion efficiency. Other components and connections are the same as in any of the specific embodiments one to sixteen.

[0118] Detailed Implementation Method Eighteen: Combining Figure 1 This embodiment describes a liquid fuel purging system C that includes a combustion chamber bleed air path CD0, a liquid fuel purging path C0-1, an atomized air purging path C0-2, a fourth regulating valve C4-1, a fifth regulating valve C4-2, a fourth flow sensor C6-1, a fifth flow sensor C6-2, a fourth check valve C8-1, and a fifth check valve C8-2.

[0119] Liquid fuel purging path C0-1 and atomizing air purging path C0-2 are connected in parallel and share the combustion chamber bleed air path CD0. Liquid fuel purging path C0-1 is connected to liquid fuel pipeline A0 after being connected in series with a fourth regulating valve C4-1, a fourth flow sensor C6-1, and a fourth check valve C8-1. Atomizing air purging path C0-2 is connected to auxiliary atomizing air path E0 after being connected in series with a fifth regulating valve C4-2, a fifth flow sensor C6-2, and a fifth check valve C8-2. This configuration facilitates purging of liquid fuel when using gaseous fuel, preventing carbon buildup. Other components and connections are the same as in specific embodiments one through seventeen.

[0120] Detailed Implementation Method Nineteen: Combining Figure 1 This embodiment describes a gaseous fuel purging system D, which includes a first branch purging path D0-1, a second branch purging path D0-2, a sixth regulating valve D4-1, a seventh regulating valve D4-2, a sixth flow sensor D6-1, a seventh flow sensor D6-2, a sixth check valve D8-1, and a seventh check valve D8-2.

[0121] The first branch purge path D0-1 and the second branch purge path D0-2 of the gaseous fuel flow path are connected in parallel and share the combustion chamber bleed air path CD0. The first branch purge path D0-1 is connected to the first branch B0-1 of the gaseous fuel flow path after being connected in series with a sixth regulating valve D4-1, a sixth flow sensor D6-1, and a sixth check valve D8-1. The second branch purge path D0-2 is connected to the second branch B0-2 of the gaseous fuel flow path after being connected in series with a seventh regulating valve D4-2, a seventh flow sensor D6-2, and a seventh check valve D8-2. This arrangement facilitates gas path purging during fuel switching. Other components and connections are the same as in any of the specific embodiments one to eighteen.

[0122] Combination Figures 1 to 6 Explanation of the working principle of this invention:

[0123] like Figure 1 As shown, the main body of the gas turbine consists of a compressor 7, a combustion chamber 8, a low-emission dual-fuel control system, and a turbine 9. It drives a generator 10 to generate electricity, forming a gas turbine generator set. A ring pipe is installed at the head of the combustion chamber 8 to facilitate fuel distribution, such as the low-emission nozzle ring pipe system F in the enlarged view G. Specifically, it includes liquid fuel ring pipes 1-9H, auxiliary atomizing air ring pipes 4-1H, gaseous fuel I-path ring pipes 2-1H, and gaseous fuel II-path ring pipes 3-1H, which are connected to the corresponding liquid fuel inlet pipes 1-9, auxiliary atomizing air inlet 4-1, gaseous fuel I-path inlet 2-1, and gaseous fuel II-path inlet 3-1 of the low-emission nozzle 11 via branch pipes (view G).

[0124] Liquid fuel system A is connected to liquid fuel loop 1-9H via liquid fuel flow path A0, with the connection point located in the lower half of the loop. Gas fuel system B is divided into gas fuel branch 1 B0-1 and gas fuel branch 2 B0-2 via gas fuel flow path B0, respectively connected to gas fuel loop 1 2-1H and gas fuel loop 2 3-1H. The two branches share a gas fuel source B1, a water bath heater B2, a filter B3, a shut-off valve B5, and a vent valve B7. They also have separate regulating valves, shut-off valves, flow meters, and check valves. Auxiliary atomizing air system E is connected to auxiliary atomizing air loop 4-1H via auxiliary atomizing air flow path E0, primarily assisting liquid fuel in atomization. Droplet breakup enhances combustion and improves efficiency. The liquid fuel purging system C is divided into two flow paths: liquid fuel purging path C0-1 and atomizing air purging path C0-2. These are connected downstream of check valves A8 and E8 in the liquid fuel flow path A0 and auxiliary atomizing air flow path E0, respectively. They clean and purge the internal channels of the liquid fuel loop and low-emission nozzles when not in operation to prevent carbon buildup and assist in atomization. Similarly, the gaseous fuel purging system D is divided into two flow paths: the first branch purging path D0-1 and the second branch purging path D0-2. These clean and purge the internal channels of the gaseous fuel loop and low-emission nozzles when not in operation, while preventing backfire and spontaneous combustion. Furthermore, the liquid fuel system A, gaseous fuel system B, and auxiliary atomizing air system E each have independent media sources: liquid fuel source A1, gaseous fuel source B1, and compressed air source E1. The purge air for the liquid fuel purging system C and the gaseous fuel purging system D originates from the high-pressure gas in the annular cavity 8A of combustion chamber B, and is supplied to purging systems C and D via the combustion chamber bleed air path CD0. The upper bleed air point of the combustion chamber is located on the outer wall of the combustion chamber casing. All five systems in this invention employ an independent modular design, allowing for individual skid-mounted installation and transportation, making them particularly suitable for space-constrained locations such as offshore platforms.

[0125] like Figure 1As shown in view G, the low-emission dual-fuel combustor 8 consists of a combustor outer shell 8-1, an inner shell 8-2, a front support shell 8-4, a rear support shell 8-5, a low-emission dual-fuel low-emission nozzle 11, a flame tube 8-3, a diffuser 8-6, and a positioner 8-7. The low-emission dual-fuel low-emission nozzle 11 passes through the mounting hole on the front annular conical surface of the front support shell 8-4 and is inserted into the head insertion hole of the flame tube 8-3, and is fixed and sealed by a low-emission nozzle mounting flange. The flame tube 8-3 has a cylindrical structure, with a flame tube, a main combustion port 8-3A, and a film cooling hole on the middle section. The main combustion port provides supplementary air mixed with fuel to reduce the temperature of the main combustion zone and enhance emission reduction; it also adjusts the uniformity of the combustor outlet temperature distribution, improving the overall overhaul period of the unit. The flame tube 8-3 has a low-emission nozzle insertion mounting hole at the head and a mounting base at the tail, connecting two positioners 8-7 at the head and one mounting flange at the tail. The combustion chamber is fixed by three points, providing a stable and efficient high-temperature flame working space. The outer shell 8-1 of the combustion chamber is connected to the front load-bearing shell 8-4 and the rear support shell 8-5 through the front and rear annular flanges to ensure sealing. The inner shell 8-2 of the combustion chamber is connected to the front load-bearing shell 8-4 through the front annular flange, and together with the outer shell 8-1 of the combustion chamber, they form a three-dimensional annular working space 8A, namely a high-temperature and high-pressure air passage annular cavity. The diffuser 8-6 is connected to the rear of the inner shell 8-2 of the combustion chamber to provide a high-temperature and high-pressure air intake channel for the combustion chamber. The rear support shell 8-5 of the combustion chamber is used to provide a mounting base for the flame tube and a high-temperature combustion chamber outlet 8-5A, so that the high-temperature gas impacts the working blades of the turbine 9.

[0126] When the combustion chamber is working, high-temperature and high-pressure air from the compressor 7 enters the diffuser 8-6 through the combustion chamber inlet 8-6A, is decelerated and diffused, and then flows into the combustion chamber annular cavity 8A. The air is then distributed to the first-stage air cyclone, the second-stage air cyclone, and the main combustion port and film cooling port of the flame tube 8-3 of the low-emission dual-fuel low-emission nozzle 11. The former mixes with liquid fuel or gaseous fuel to form a combustible mixture, which burns efficiently and stably in the flame tube 8-3. The latter forms supplementary combustion air to further reduce emissions and cool the flame tube 8-3 so that the material does not exceed the temperature resistance limit. Finally, the high-temperature gas is discharged from the combustion chamber outlet 8-5A, which drives the turbine 9 to output power and generate electricity.

[0127] When combustion chamber 8 operates using gaseous fuel, a two-stage lean premixing method is used to achieve uniform mixing of gaseous fuel and air. The air volume ratio of the first-stage air cyclone separator to the second-stage air cyclone separator is 1:7, which matches the fuel supplied by the first and second gaseous fuel lines. This controls the total equivalence ratio of the two-stage combustion zones within the low-emission range of 2.5 to 4.5, thereby ensuring that the combustion zone temperature is within the low-emission combustion temperature control range of 1700℃ to 1900℃. This achieves a highly efficient and stable combustion chamber while controlling NOx emissions within the low-emission range.

[0128] like Figure 2 As shown, the liquid fuel cyclone separator 1-1 is installed in the inner cavity of the atomizing air cyclone separator 1-2 via a plug-in connection, forming a liquid fuel channel together with its inner wall surface. The screw plug 1-4 is fixed to the atomizing air cyclone separator 1-2 via a threaded connection, and then presses and fixes the liquid fuel cyclone separator 1-1 by compression to ensure good sealing and installation concentricity. The atomizing air cyclone separator 1-2 is also installed in the inner cavity of the cap 1-3 via a plug-in connection, and is simultaneously assembled with the housing 5-1 via a plug-in connection. The plug 1-14 is fixed to the housing 5-1 via a threaded connection and rotates to apply a rated torque, causing the ring 1-15 and the sealing ring 1-16 to compress the sealing cover 1-17, thereby ensuring the seal between the housing 5-1 and the plug 1-14, and fixing the atomizing air cyclone separator 1-2.

[0129] (1) When using liquid fuel: the liquid fuel in the liquid fuel source A1 is pressurized by pump A2, filtered by the first filter A3 to remove impurities, and transported to the liquid fuel loop pipe 1-9H under the condition of the first regulating valve A4 with appropriate opening and the first shut-off valve A5 fully open, and finally supplied to the low emission nozzle 11 through the branch pipe. During this process, the vent valve A7 remains closed. Figure 1 Liquid fuel enters the liquid fuel inlet pipe 1-9, is filtered by the liquid fuel filter assembly 1-12, and then flows through the channel formed by the sealing cap 1-17 and the screw plug 1-4 to the liquid fuel cyclone separator 1-1, where it reaches a cyclone state. Finally, it is injected from the liquid fuel nozzle inside the atomizing air cyclone separator 1-2, forming an atomizing cone, and enters the combustion space to mix and burn with compressed air. During this process, the gaseous fuel purging system D is in the open state, and the sixth regulating valve D4-1 and the seventh regulating valve D4-2 are at appropriate openings to control the purging air volume. Figure 1Compressed air is supplied to the gas fuel inlet 2-1 (referring to the first gas fuel inlet pipe 2-1) and the gas fuel inlet 3-1 (referring to the second gas fuel inlet pipe 3-1) to purge and cool the gas fuel passage and prevent backflow of high-temperature gas when the low-emission nozzle is working. Depending on the operating conditions of the gas turbine, the auxiliary atomizing air path will have two different operating states.

[0130] (2) When using liquid fuel in low operating conditions: When the gas turbine uses liquid fuel and is running in ignition and idle conditions, the auxiliary atomizing air from the air compressor, that is, part of the gas in the compressed air source E1, is adjusted to a suitable flow rate through the orifice plate E2. With the fifth shut-off valve E5 fully open, it enters the auxiliary atomizing air ring pipe 4-1H and branch pipe through the eighth flow sensor E6 and the eighth check valve E8, and is finally supplied to the atomizing air channel of the low emission nozzle 11. The atomizing air is actively supplied through the atomizing air inlet 4-1. The atomizing air interface is sealed and connected through the atomizing air connecting nut 4-2 and the atomizing air connecting cone 4-3. The air enters the auxiliary atomizing air channel 1-5, and then passes through the swirling channel space and swirling groove formed by the low emission nozzle housing 5-1, the atomizing air swirler 1-2, and the cap 1-3 to achieve a swirling state. Finally, the air is ejected through the atomizing air nozzle formed by the atomizing air swirler 1-2 and the cap 1-3, which rotates and shears the liquid fuel atomizing cone liquid film to assist in the breakup of liquid droplets, achieving a good atomization effect and solving the problem of poor liquid fuel atomization quality during gas turbine idle and ignition conditions.

[0131] (3) When using liquid fuel at high operating conditions: When the gas turbine uses liquid fuel and operates above idle speed, the auxiliary atomizing air system E closes the shut-off valve E5 at the moment the idle speed condition is reached, stopping the external auxiliary atomizing air supply. The atomizing air supply to the atomizing air ring pipe 4-1H, branch pipes, and low-emission nozzle atomizing air passage is adjusted to be supplied by the atomizing air purging path C0-2 of the atomizing air purging system C, and the regulating valve C4-2 is opened to a suitable degree. That is, the auxiliary atomizing air source is supplied by the compressed air in the annular cavity space formed by the combustion chamber shell and the combustion chamber flame tube of the gas turbine. At this time, the air compressor can stop working, and only the high-pressure air from the rotation and compression of the gas turbine compressor is used for auxiliary atomization.

[0132] (4) When using gaseous fuel at low operating conditions: When the gas turbine uses gaseous fuel and operates in ignition and idle conditions, the gaseous fuel system B is in operation. The gaseous fuel in the gaseous fuel source B1 is filtered and purified by the fully open third shut-off valve B5-1 and the second filter B3, and then heated by the water bath heater B2 before entering the first gaseous fuel branch B0-1. At this time, the third regulating valve B4-2 and the fourth shut-off valve B5-2 of the second gaseous fuel flow path are both kept completely closed. After passing through the appropriately opened second regulating valve B4-1 and the fully opened fourth shut-off valve B5-2, the gaseous fuel is transported to the ring pipe 2-1H under the measurement of the flow sensor B6-2, and finally supplied to the low emission nozzle 11 through the branch pipe. During this process, the vent valve B7 remains closed. Figure 1 Gaseous fuel is supplied from the gaseous fuel inlet 2-1. The gaseous fuel inlet 2-1 is sealed via the gaseous fuel inlet nut 2-2 and the gaseous fuel inlet cone 2-3. The gaseous fuel is delivered through the hole in the low-emission nozzle housing 5-1 to the fuel orifice in the first air cyclone separator 2-5 after the fuel channel is formed by the low-emission nozzle housing 5-1 and the bow-shaped clamp 2-4, and then sprayed out. After mixing with air, it enters the combustion space for premixed combustion, effectively reducing pollutant emissions. During this process, the second branch of the gaseous fuel purging system D, the purging path D0-2, is in the open state, and the third regulating valve B4-2 is at an appropriate opening to control the purging gas volume to the gaseous fuel second loop pipe 3-1H. Figure 1 The gaseous fuel enters the gaseous fuel II inlet 3-1 of the low-emission nozzle 11. Similarly, when the liquid fuel purging system C is in purging operation, the atomizing air inlet 4-1 and the liquid fuel inlet 1-9 are supplied with compressed air from the annular space formed by the gas turbine combustion chamber shell and the combustion chamber flame tube to purge and cool each channel and prevent backflow of high-temperature gas during the operation of the low-emission nozzle. Optionally, the liquid fuel purging path C0-1 and the atomizing air purging path C0-2 include a fourth regulating valve C4-1 and a fifth regulating valve C4-2 to control the flow rate, and a fourth flow sensor C6-1 and a fifth flow sensor C6-2 to measure the actual purging flow rate. At the same time, the eighth check valve E8 and the first check valve A8 prevent the purging gas from flowing back into the auxiliary atomizing air system E and the liquid fuel system A, thus preventing damage to the equipment.

[0133] (5) When using gaseous fuel under high operating conditions: When the gas turbine uses gaseous fuel and operates above idle speed, the gaseous fuel supply is relatively large. When the idle speed point is reached, the gaseous fuel loop 2 is adjusted from the purging state to the fuel supply state, that is, the seventh regulating valve D4-2 is adjusted from the open state to the closed state. At the same time, the seventh regulating valve D4-2 is adjusted to a suitable opening degree, and the fourth shut-off valve B5-2 is adjusted to be fully open. Both branches of the gaseous fuel system B are in the fuel supply operating state. Specifically, the gas in the gaseous fuel source B1... Fuel passes through the fully open second shut-off valve B5 and the second filter B3 for filtration and impurity removal. After being heated by the water bath heater B2, it enters the first gaseous fuel branch B0-1 and the second gaseous fuel flow path B0-2. Through appropriately opened regulating valves and the fully open shut-off valve, under the metering conditions of their respective flow sensors, the gaseous fuel is transported to the first gaseous fuel loop 2-1H and the second gaseous fuel loop 3-1H, and finally supplied to the low-emission nozzle 11 via branch pipes. During this process, the vent valve B7 remains closed. If the operating conditions continue to increase, the opening of the second regulating valve B4-1 and the third regulating valve B4-2 is controlled. Figure 1 At this time, gaseous fuel is supplied simultaneously from gaseous fuel inlet 2-1 and gaseous fuel inlet 3-1. In addition to gaseous fuel inlet 1, gaseous fuel inlet 2 is sealed through gaseous fuel inlet 2 nut 3-2 and gaseous fuel inlet 2 cone 3-3. The gaseous fuel is then transported through the housing 5-1 and the holes in the first-stage air cyclone 2-5 to the fuel channel formed by the second-stage cyclone 2-9 and the cover 3-4, and then enters the fuel orifice in the second-stage cyclone 2-9 and is ejected. After mixing with air, it enters the combustion space and undergoes premixed combustion together with gaseous fuel inlet 1. During this process, the liquid fuel purging system C is in the same working state as when the gas turbine is operating under low-condition gaseous fuel. The atomizing air inlet 4-1 and the liquid fuel inlet 1-9 are both supplied with compressed air from the annular cavity space formed by the gas turbine combustion chamber shell and the combustion chamber flame tube to purge and cool each channel and prevent backflow of high-temperature gas when the low-emission nozzle is working.

[0134] (6) When switching from gaseous fuel to liquid fuel under a certain operating condition, the following steps may be optionally followed:

[0135] ① Before the switchover begins, the gaseous fuel system B remains operational, meaning that gaseous fuel is supplied from gaseous fuel branch line 1 B0-1 and gaseous fuel branch line 2 B0-2 to gaseous fuel loop 1 2-1H and gaseous fuel loop 2, and then enters the low-emission nozzle 11 for combustion; the liquid fuel purging system C remains operational, meaning that the bleed air from the combustion chamber 8 enters the liquid fuel purging flow path C0-1 and atomized air purging path C0-2 through flow path CD0, and then enters the liquid fuel loop 1-9H and auxiliary atomized air loop 4-1H respectively, effectively purging the liquid fuel passage and auxiliary atomized air passage of the low-emission nozzle 11 to prevent carbon buildup; the liquid fuel system A, gaseous fuel purging system D, and auxiliary atomized air system E are not operational, and effectively check the bleed air and gaseous fuel in the combustion chamber 8 through their respective first check valve A8, sixth check valve D8-1, seventh check valve D8-2, and eighth check valve E8 to prevent fuel backflow and gas turbine malfunction;

[0136] ② At the start of the switchover, based on the state in step ①, the liquid fuel purging flow path C0-1 of the liquid fuel purging system C stops working, that is, the fourth regulating valve C4-1 is adjusted to the closed state, the liquid fuel system A starts working, pump A2 starts, the first shut-off valve A5 opens, the first regulating valve A4 is adjusted to the minimum valve opening, and the working medium in the liquid fuel ring pipe 1-9H is changed from the bleed air of the combustion chamber 8 to liquid fuel supplied by the liquid fuel flow path A0 at a suitable flow rate Gl, and finally enters the liquid fuel channel of the low emission nozzle 11. Under the purging air assisted atomization under the bleed air conditions of the combustion chamber 8, it enters the combustion chamber to participate in combustion. At the same time, in order to ensure that the power fluctuation of the gas turbine generator set is within 5%, the second regulating valve B4-1 and the third regulating valve of the gas fuel system are adjusted. Valve B4-2 reduces its opening by a certain degree to reduce the amount of gaseous fuel Gg corresponding to the calorific value of Gl. As the fuel switching process progresses, the opening of the first shut-off valve A5 gradually increases, while the openings of the third shut-off valve B5-1 and the fourth shut-off valve B5-2 gradually decrease. During this process, the power fluctuation of the gas turbine generator set is kept within 5%. When a certain moment is reached, the second regulating valve B4-1 and the third regulating valve B4-2 are completely closed, and at the same time, the third shut-off valve B5-1 and the fourth shut-off valve B5-2 are also adjusted to the closed state to ensure effective cut-off of gaseous fuel. The first shut-off valve A5 is adjusted to a suitable opening to complete the fuel switching. During this operation of the gas turbine generator set, there is continuous power output, and the generator 10 remains in a stable operating state.

[0137] ③ After the switching is completed, based on step ②, the liquid fuel system A remains in operation, the gas system B is in a closed state, the second shut-off valve B5, the third shut-off valve B5-1 and the fourth shut-off valve B5-2 are all closed, and the gas purging system D starts to work, that is, the sixth regulating valve D4-1 and the seventh regulating valve D4-2 are opened to a suitable degree, and the bleed gas from the combustion chamber 8 is introduced into the gas fuel 1 loop pipe 2-1H and the gas fuel 2 loop pipe respectively to purge and clean the two gas fuel channels of the low emission nozzle 11, preventing carbon buildup and backfire. At the same time, the second check valve B8-1 and the third check valve B8-2 of the first and second branches of the gas fuel flow path of the gas fuel system B can effectively prevent the purging gas from flowing back into the interior of the gas fuel system B, generating a flammable mixture, and affecting the reuse of the gas fuel. Alternatively, the vent valve B7 of the gas fuel system B can be opened to safely vent the residual gas fuel in the gas fuel flow path through the vent port, preventing the formation of flammable mixtures and ensuring the safety of the unit. After venting, the vent valve B7 is adjusted to be closed to restore the system to standby status.

[0138] (7) When switching from liquid fuel to gaseous fuel under a certain operating condition, the following steps may be optionally followed:

[0139] ① Before the switchover begins, the liquid fuel system A remains operational, meaning that liquid fuel is supplied from liquid fuel source A1 through liquid fuel flow path A0 to liquid fuel ring pipe 1-9H, and finally enters the liquid fuel channel of low emission nozzle 11 for injection, atomization, and combustion. The gaseous fuel system B is closed, and the gaseous fuel purging system D is operational, meaning that the sixth regulating valve D4-1 and the seventh regulating valve D4-2 are opened to appropriate openings, purging the combustion chamber 8 through the first branch of the gaseous fuel flow path, purging path D0-1. The second branch of the gas fuel flow path, the purging path D0-2, is introduced into the first gas fuel loop 2-1H and the second gas fuel loop respectively to purge and clean the two gas fuel channels of the low emission nozzle 11, preventing carbon buildup and backfire. At the same time, the second check valve B8-1 and the third check valve B8-2 of the first and second branches of the gas fuel flow path of the gas fuel system B can effectively prevent the purging gas from flowing back into the interior of the gas fuel system B, generating a flammable mixture and affecting the gas fuel's restart. The liquid fuel purging system C remains in a semi-operational state, meaning that the liquid fuel purging flow path C0-1 is closed, but the auxiliary atomizing air flow path C0-2 is open. The bleed air from the combustion chamber 8 enters the atomizing air purging path C0-2 through the flow path CD0, and further enters the auxiliary atomizing air ring 4-1H, ultimately effectively purging the auxiliary atomizing air channel of the low emission nozzle 11. After being sprayed out of the channel outlet, it assists in the efficient atomization of liquid fuel, enhancing combustion and improving combustion efficiency. The auxiliary atomizing air system E is not in operation, and the bleed air from the combustion chamber 8 is effectively prevented from flowing back into the auxiliary atomizing air system through the check valve E8, preventing the bleed air from damaging the equipment.

[0140] ② At the start of the switching, based on the state in step ①, the first branch purging path D0-1 and the second branch purging path D0-2 of the gaseous fuel purging system D stop working. That is, the sixth regulating valve D4-1 and the seventh regulating valve D4-2 are adjusted to the closed state, stopping purging and preparing for the switching. Further, the second shut-off valve B5 on the gaseous fuel flow path B0 opens, and the water bath heater B2 begins to heat the gaseous fuel supplied by the gaseous fuel source B1 to prevent hydrocarbon precipitation caused by excessively low fuel temperature. The second regulating valve B4-1 of the first branch of gaseous fuel B0-1 opens to its minimum position, and the third shut-off valve B5-2 is adjusted to the open position. Gaseous fuel is then supplied through the flow path to the gaseous fuel 1 loop pipe 2-1H, controlling the gaseous fuel flow rate to Gg. The fuel then enters the gaseous fuel 1 channel of the low-emission nozzle 11 and participates in combustion. Simultaneously, the first regulating valve A4 on the liquid fuel flow path A0 reduces its opening, decreasing the liquid fuel flow rate by Gl. Since Gl and Gg have the same calorific value, the power output of the gas turbine generator set is stabilized within 5%. As the switching process progresses, when the second regulating valve B4-1 is adjusted to a certain opening, the opening remains unchanged. The fourth shut-off valve B5-2 is adjusted to the open position, and the third regulating valve B4-2 is adjusted to its minimum opening. Simultaneously, the first regulating valve A4 of the liquid fuel system A continues to reduce its opening until it closes. The gaseous fuel system B is fully engaged in a stable operating state, completing the fuel switching. During this process, the gas turbine generator set maintains a stable operating state with continuous power output, and the generator 10 remains in a stable operating state.

[0141] ③ After the switchover is completed, based on step ②, the liquid fuel system A has stopped working, meaning pump A2, the first regulating valve A4, and the first shut-off valve A5 are all closed. The gas fuel system B is in an open and stable operating state. The liquid fuel purging system C starts working, meaning the fourth regulating valve C4-1 opens to a suitable degree, introducing bleed air from the combustion chamber 8 into the liquid fuel ring pipes 1-9H to purge and clean the liquid fuel passage of the low-emission nozzle 11, preventing carbon buildup. Simultaneously, the check valve A8 on the liquid fuel flow path A0 of the liquid fuel system A effectively prevents purging air from flowing back into the liquid fuel system A, generating a flammable mixture and affecting the reuse of the liquid fuel. Furthermore, the vent valve A7 in the liquid fuel system A can optionally be opened to release residual liquid fuel in the liquid fuel flow path through the vent port to ensure unit safety before being closed, restoring the system to standby status.

[0142] (8) To prevent high-temperature carbon buildup in the dual-fuel low-emission nozzles, a three-channel anti-carbon-deposit air-cooling channel is installed, the specific composition of which is as follows:

[0143] To reduce the temperature of the cap 1-3 and prevent carbon buildup, multiple holes are made on the cyclone housing 2-10 when the dual-fuel low-emission nozzle is working. Unburned compressed air from the annular cavity between the combustion chamber shell and the flame tube flows into the low-emission nozzle through the anti-carbon buildup cold purge hole 6-1 and flows through the cooling channel inside the cap 1-3. Finally, it is sprayed out into the combustion space from the anti-carbon buildup cold purge nozzle 6-2, forming a heat-insulating protective gas mold, reducing the temperature and preventing carbon buildup. To reduce the temperature of the premixed first-path clamping component 2-6 and prevent carbon buildup, multiple holes are opened on the cyclone shell 2-10 when the dual-fuel low-emission nozzle is working. Unburned compressed air from the annular cavity between the combustion chamber shell and the flame tube flows into the low-emission nozzle through the second-path anti-carbon-deposit cold purge holes 6-3 and flows within the cooling channel formed by the cyclone shell 2-10, the premixed first-path clamping component 2-6, and the first cup-shaped assembly 2-7. Under the action of pressure difference, the premixed first-path clamping component 2-6 is subjected to impact cooling through the multiple rows of holes on the first cup-shaped assembly 2-7. Finally, the second-path anti-carbon-deposit cold purge nozzle 1 6-4 and the second-path anti-carbon-deposit cold purge nozzle 2-5 are sprayed into the combustion space to form a heat-insulating protective gas film, reduce the temperature, and prevent carbon buildup. To reduce the temperature of the premixed second-path clamping component 3-6 and prevent carbon buildup, multiple holes are made on the collar 3-5 when the dual-fuel low-emission nozzle is working. Unburned compressed air from the annular cavity between the combustion chamber shell and the flame tube flows into the low-emission nozzle through the three-path cooling and anti-carbon-deposit cold purge holes 6-6, and flows within the cooling channel formed by the cyclone shell 2-10, the collar 3-5, and the premixed second-path clamping component 3-6. Finally, it is sprayed out into the combustion space through multiple small holes on the premixed second-path clamping component 3-6, forming a heat-insulating protective gas film, reducing the temperature, and preventing carbon buildup.

[0144] The above description only illustrates preferred embodiments of the present invention. However, the present invention is not limited to the specific embodiments described above. Under the guidance of the present invention, those skilled in the art can make various modifications or equivalent substitutions to the features and embodiments of the present invention to adapt to specific circumstances without departing from the spirit of the invention and the protection scope of the claims.

Claims

1. A low-emission nozzle, characterized in that: It includes a first fuel gas path, a second fuel gas path, an atomizing air path, a liquid fuel path, a purging air path, and a nozzle body; The first fuel gas path, the second fuel gas path, the atomizing air path, and the liquid fuel path are installed on the nozzle body in an internal oil and external gas configuration with the oil and gas paths interleaved. The atomizing air path, the first fuel gas path, and the liquid fuel path ensure the unit enters idle operating condition and share the first air cyclone separator (2-5) of the first fuel gas path. The atomizing air path, the second fuel gas path, and the liquid fuel path ensure the unit enters fast operating condition and share the second air cyclone separator (2-9) of the second fuel gas path. The purging air path is installed on the fuel discharge side of the nozzle body and employs impact convection cooling, film cooling, and thermal insulation cooling to prevent carbon buildup at the nozzle. The first fuel gas path includes the first air cyclone separator (2-5), the premixed first-path clamping component (2-6), and the first cup-shaped assembly (2-7). The second fuel gas path includes the second-path cyclone separator housing (2-10), the collar (3-5), and the premixed second-path clamping component (3-6). The atomizing air path includes a cap (1-3). The purge air path includes an impingement convection cooling air path, a film cooling air path, and an insulation cooling air path, wherein: The impact convection cooling gas path is as follows: multiple dual-path anti-carbon buildup cold state purging holes (6-3) are opened on the second-path cyclone shell (2-10), and external cold air flows in from the multiple dual-path anti-carbon buildup cold state purging holes (6-3); it flows in the internal cooling channel formed by the second-path cyclone shell (2-10), the premixed first-path clamping component (2-6) and the first cup-shaped component (2-7), and under the action of gas pressure difference, it impacts and cools the premixed first-path clamping component (2-6) through the multiple rows of holes on the first cup-shaped component (2-7); The air film cooling air path is as follows: The first air cyclone separator (2-5) has multiple anti-carbon buildup cold state purging holes (6-1). The cold air from the external purging system enters from the multiple anti-carbon buildup cold state purging holes (6-1); it flows through the cooling channel inside the cap (1-3) and is finally sprayed out from the anti-carbon buildup cold state purging nozzle (6-2) into the combustion space to form a heat insulation protective air film and reduce the temperature of the cap (1-3); The heat insulation and cooling air path is as follows: multiple three-way cooling and anti-carbon-deposit cold-state purging holes (6-6) are opened on the collar (3-5). The cold air of the external purging system enters the internal cooling channel formed by the second-way cyclone shell (2-10), collar (3-5) and premixed second-way pressing component (3-6) through the multiple three-way cooling and anti-carbon-deposit cold-state purging holes (6-6), and finally sprays out from the multiple holes on the premixed second-way pressing component (3-6) into the combustion space to form a heat insulation and protective air film, thereby reducing the temperature of the premixed second-way pressing component (3-6).

2. The low-emission nozzle according to claim 1, characterized in that: The nozzle body includes a low-emission nozzle housing (5-1) and a combustion chamber cover plate (5-2), which is installed on the fuel inlet of the low-emission nozzle housing (5-1).

3. A low-emission nozzle according to claim 2, characterized in that: The liquid fuel circuit includes a liquid fuel cyclone separator (1-1), a screw plug (1-4), a sealing cap (1-17), a sealing assembly, a screw plug (1-14), a liquid fuel heat insulation pipe (1-13), a liquid fuel circuit inlet pipe (1-9), a liquid fuel circuit connection cap (1-10), a liquid fuel circuit connection cone pipe (1-11), and a liquid fuel filter assembly (1-12). The liquid fuel circuit connection cone pipe (1-11) is inserted into the combustion chamber cover plate (5-2), and the liquid fuel filter assembly (1-12) is installed inside the liquid fuel circuit connection cone pipe (1-11). The liquid fuel inlet pipe (1-9) is installed on the liquid fuel connection cone pipe (1-11) through the liquid fuel connection cap (1-10). The liquid fuel cyclone separator (1-1) and the screw plug (1-4) are coaxially installed inside the low emission nozzle housing (5-1). The sealing cap (1-17) seals the screw plug (1-4) through the sealing assembly. The screw plug (1-14) is screwed onto the sealing cap (1-17). The two ends of the liquid fuel heat insulation pipe (1-13) are connected to the liquid fuel cyclone separator (1-1) and the liquid fuel connection cone pipe (1-11) respectively.

4. A low-emission nozzle according to claim 3, characterized in that: The sealing assembly includes a circular ring (1-15), a sealing ring (1-16), and a steel ring (1-18). The sealing ring (1-16) is an annular sealing ring. The upper part of the sealing ring (1-16) is provided with a tapered stepped groove (1-16-1). The steel ring (1-18) is sealed and embedded in the sealing ring (1-16). The lower outer side of the circular ring (1-15) is tapered and stepped. The circular ring (1-15) is inserted into the stepped groove (1-16-1) of the sealing ring (1-16), and the upper end face of the circular ring (1-15) is lower than the upper end face of the sealing ring (1-16).

5. A low-emission nozzle according to claim 1, 2, 3 or 4, characterized in that: The atomizing air path also includes an atomizing air cyclone separator (1-2), an auxiliary atomizing air path inlet pipe (1-6), an auxiliary atomizing air path connecting cap (1-7), and an auxiliary atomizing air path cone pipe (1-8). The atomizing air cyclone separator (1-2) is fitted onto the liquid fuel cyclone separator (1-1) and the screw plug (1-4). The cap (1-3) is fitted onto the atomizing air cyclone separator (1-2) and located on one side of the liquid fuel cyclone separator (1-1). The auxiliary atomizing air path inlet pipe (1-6) is installed on the combustion chamber cover plate (5-2). The auxiliary atomizing air path inlet pipe (1-6) is connected to the auxiliary atomizing air path cone pipe (1-8) through the auxiliary atomizing air path connecting cap (1-7). The bottom of the auxiliary atomizing air path cone pipe (1-8) is connected to the atomizing air cyclone separator (1-2) through the auxiliary atomizing air channel (1-5).

6. A low-emission nozzle according to claim 5, characterized in that: The first fuel gas path also includes a first gaseous fuel inlet pipe (2-1), a first gaseous fuel connecting cap (2-2), a first gaseous fuel connecting cone pipe (2-3), an arc-shaped clamp (2-4), and a second cup-shaped assembly (2-8). The first gas fuel connecting cone (2-3) is installed on the combustion chamber cover (5-2). The first gas fuel inlet pipe (2-1) is installed on the first gas fuel connecting cone (2-3) through the first gas fuel connecting cap (2-2). The bow-shaped clamp (2-4) is installed on the fuel injection side end of the low emission nozzle housing (5-1). The first air cyclone separator (2-5) is installed at the rear end of the bow-shaped clamp (2-4). The premixed first-path clamping member (2-6) is coaxially inserted with the first air cyclone separator (2-5) at the tail end of the first air cyclone separator (2-5). The first cup-shaped assembly (2-7) and the second cup-shaped assembly (2-8) are fitted onto the premixed first-path clamping member (2-6) from the inside to the outside. The bottom of the first gas fuel connecting cone (2-3) is connected to the first air cyclone separator (2-5) through the first gas passage.

7. A low-emission nozzle according to claim 6, characterized in that: The second fuel gas path also includes a second air cyclone separator (2-9), a second gas fuel inlet pipe (3-1), a second gas fuel connecting cap (3-2), a second gas fuel connecting cone pipe (3-3), and a cover (3-4). The second-path cyclone shell (2-10) is installed on the first-path air cyclone (2-5) through the cover (3-4). The second-path air cyclone (2-9) is installed on the second-path cyclone shell (2-10). The premixed second-path clamping member (3-6) is installed on the second-path cyclone shell (2-10) through the collar (3-5). The second gas fuel connecting cone (3-3) is installed on the combustion chamber cover plate (5-2). The second gas fuel inlet pipe (3-1) is connected to the second gas fuel connecting cone (3-3) through the second gas fuel connecting cap (3-2). The second gas fuel connecting cone (3-3) and the second-path air cyclone (2-9) are connected through the second gas passage.

8. A low-emission nozzle according to claim 7, characterized in that: The cold air from the external purging system is ejected into the combustion space through the first nozzle (6-4) and the second nozzle (6-5) of the second anti-carbon-deposit cold purging system, forming a heat-insulating protective gas film. Finally, the temperature of the premixed first-path clamping component (2-6) is reduced by a combination of impact convection cooling and gas film cooling.

9. A low-emission nozzle according to claim 8, characterized in that: The first nozzle (6-4) and the second nozzle (6-5) for preventing carbon buildup and cold purging are both arranged in a ring array on the first premixed clamping component (2-6).

10. A low-emission nozzle according to claim 9, characterized in that: The second-path anti-carbon buildup cold purging nozzle (6-4) is an elliptical nozzle, and multiple second-path anti-carbon buildup cold purging nozzles (6-4) are arranged in a clockwise inclined ring array.

11. A low-emission nozzle according to claim 10, characterized in that: The second-path anti-carbon buildup cold purging nozzle (6-5) is a rectangular nozzle.

12. A low-emission dual-fuel combustion chamber, comprising a combustion chamber outer shell (8-1), a combustion chamber inner shell (8-2), and a flame tube (8-3), characterized in that: It also includes a front load-bearing housing (8-4), a rear support housing (8-5), a combustion chamber outlet (8-5A), a diffuser (8-6), a combustion chamber inlet (8-6A), a positioner (8-7), and a low-emission nozzle as described in claim 1. The combustion chamber outer shell (8-1) is sealed to the front load-bearing shell (8-4) and the rear support shell (8-5) through front and rear annular flanges respectively. The combustion chamber inner shell (8-2) is connected to the front load-bearing shell (8-4) through the front annular flange and together with the combustion chamber outer shell (8-1) forms a three-dimensional combustion chamber annular cavity (8A). The diffuser (8-6) is connected to the rear of the combustion chamber inner shell (8-2). The end of the diffuser (8-6) is the combustion chamber inlet (8-6A). The combustion chamber outlet (8-5A) is opened on the rear support shell (8-5). The flame tube (8-3) is installed in the annular cavity (8A) of the three-dimensional combustion chamber. The low emission nozzle passes through the mounting hole of the front annular cone surface of the front bearing housing (8-4) and is inserted into the insertion hole at the head of the flame tube (8-3). The flame tube (8-3) has a main combustion hole (8-3A) in the middle. The head of the flame tube (8-3) is connected to two positioners (8-7). The tail mounting seat of the flame tube (8-3) is mounted on the rear support housing (8-5) with three-point support.

13. A low-emission dual-fuel combustion chamber according to claim 12, characterized in that: The low-emission nozzle is the low-emission nozzle described in any one of claims 2 to 11.

14. A gas turbine generator set, characterized in that: It includes a low-emission dual-fuel combustor (8) as described in any one of claims 12-13, a low-emission dual-fuel control system, a compressor (7), a turbine (9), and a generator (10), wherein the low-emission dual-fuel combustor (8) is connected to the low-emission nozzle ring system (F) of the low-emission dual-fuel control system. High-temperature and high-pressure air from the compressor (7) enters the diffuser (8-6) through the combustion chamber inlet (8-6A) and is decelerated and diffused before flowing into the combustion chamber annular cavity (8A). The air is then distributed to the low-emission nozzle (11) and mixed with liquid or gaseous fuel to form a combustible mixture. The mixture is then efficiently and stably combusted in the flame tube (8-3) and discharged from the combustion chamber outlet (8-5A), driving the turbine (9) to output power and generate electricity for the generator (10). The low-emission dual-fuel control system includes a liquid fuel system (A), a gas fuel system (B), a liquid fuel purging system (C), a gas fuel purging system (D), an auxiliary atomizing air system (E), and a low-emission nozzle loop system (F). The low-emission nozzle loop system (F) includes a liquid fuel loop (1-9H), an auxiliary atomizing air loop (4-1H), a gas fuel first loop (2-1H), and a gas fuel second loop (3-1H). The liquid fuel loop (1-9H), the auxiliary atomizing air loop (4-1H), the gas fuel first loop (2-1H), and the gas fuel second loop (3-1H) are connected to the liquid fuel inlet pipe (1-9), the auxiliary atomizing air inlet pipe (1-6), the gas fuel first inlet pipe (2-1), and the gas fuel second inlet pipe (3-1) on the low-emission nozzle through branch pipes, respectively. When burning liquid fuel: At or below the ignition and idle operating conditions: the liquid fuel system (A) is engaged, the gas fuel system (B) is not engaged, the liquid fuel purging system (C) is not engaged, the gas fuel purging system (D) is engaged, and the auxiliary atomizing air system (E) is engaged. At this time, the liquid fuel system (A) enters the liquid fuel loop (1-9H) of the low emission nozzle loop system (F) through the liquid fuel flow path (A0), and then enters the liquid fuel path of the low emission nozzle; The auxiliary atomizing air system (E) enters the auxiliary atomizing air ring pipe (4-1H) through the auxiliary atomizing air flow path (E0), and then enters the atomizing air path of the low emission nozzle for auxiliary atomization of liquid fuel; The gaseous fuel purging system (D) is divided into two flow paths, namely the first branch purging path (D0-1) and the second branch purging path (D0-2), which clean and purge the gaseous fuel ring pipe and the internal channels of the low emission nozzle when not in operation. When the engine is running at idle speed or above: the purge air source of the atomized air path is changed from the auxiliary atomized air system (E) to the atomized air purge path (C0-2) of the liquid fuel path purge system (C). That is, the auxiliary atomized air source is supplied by compressed air in the annular cavity space formed by the combustion chamber shell and the flame tube of the low emission dual fuel combustion chamber, while the rest of the system remains unchanged. When burning gaseous fuel: The liquid fuel system (A) is shut down, the gas fuel system (B) is put into operation, and the liquid fuel purging system (C) is put into operation. At or below the ignition and idle operating conditions: Compressed air in the annular space of the low-emission dual-fuel combustion chamber enters the liquid fuel path (A0) of the liquid fuel system (A), the second branch of the gas fuel flow path (D0-2) of the gas fuel purging system (D), and the auxiliary atomizing air path (E0) of the auxiliary atomizing air system (E). Gaseous fuel enters the gaseous fuel loop (2-1H) of the low emission nozzle loop system (F) through the gaseous fuel system (B), and then enters the first gaseous fuel inlet pipe (2-1) of the low emission nozzle. The liquid fuel purging system (C) is in purging operation. The auxiliary atomizing air inlet pipe (1-6) and the liquid fuel inlet pipe (1-9) are both supplied with compressed air from the annular cavity space formed by the combustion chamber shell and the flame tube of the low-emission dual-fuel combustion chamber to purge and cool each channel. At or above the slow speed condition: When the gaseous fuel purging system (D) is closed, the gaseous fuel enters the gaseous fuel first loop (2-1H) and gaseous fuel second loop (3-1H) of the low emission nozzle loop system (F) simultaneously through the gaseous fuel system (B), and then enters the first fuel gas path and the second fuel gas path of the low emission nozzle respectively; When switching between gaseous and liquid combustion, both the liquid fuel purging system (C) and the gaseous fuel purging system (D) are shut down, while both the liquid fuel system (A) and the gaseous fuel system (B) are activated.

15. A gas turbine generator set according to claim 14, characterized in that: The liquid fuel system (A) includes a liquid fuel source (A1), a liquid fuel pipeline (A0), a pump (A2), a first filter (A3), a first regulating valve (A4), a first shut-off valve (A5), a first flow sensor (A6), a vent valve (A7), and a first check valve (A8). One end of the liquid fuel pipeline (A0) is connected to the liquid fuel source (A1), and the other end of the liquid fuel pipeline (A0) is connected in series with the pump (A2), the first filter (A3), the first regulating valve (A4), the first shut-off valve (A5), the first flow sensor (A6), and the first check valve (A8) and then connected to the liquid fuel loop pipe (1-9H). The vent valve (A7) is connected in parallel on the liquid fuel pipeline (A0) between the first flow sensor (A6) and the first check valve (A8).

16. A gas turbine generator set according to claim 14 or 15, characterized in that: The gas fuel system (B) includes a gas fuel source (B1), a gas fuel path (B0), a water bath heater (B2), a second filter (B3), a second shut-off valve (B5), a vent valve (B7), a second regulating valve (B4-1), a third regulating valve (B4-2), a third shut-off valve (B5-1), a fourth shut-off valve (B5-2), a second flow sensor (B6-1), a third flow sensor (B6-2), a second check valve (B8-1), and a third check valve (B8-2). One end of the gas fuel line (B0) is connected to the gas fuel source (B1). The other end of the gas fuel line (B0) is connected in series with a water bath heater (B2), a second filter (B3), and a second shut-off valve (B5), and then splits into gas fuel branch 1 (B0-1) and gas fuel branch 2 (B0-2). Gas fuel branch 1 (B0-1) is connected in series with a second regulating valve (B4-1), a third shut-off valve (B5-1), a second flow sensor (B6-1), and a second check valve (B8-1), and then connected to gas fuel first loop pipe (2-1H). Gas fuel branch 2 (B0-2) is connected in series with a third regulating valve (B4-2), a fourth shut-off valve (B5-2), a third flow sensor (B6-2), and a third check valve (B8-2), and then connected to gas fuel second loop pipe (3-1H).

17. A gas turbine generator set according to claim 16, characterized in that: The auxiliary atomizing air system (E) includes a compressed air source (E1), an auxiliary atomizing air path (E0), a throttling orifice plate (E2), a fifth shut-off valve (E5), an eighth flow sensor (E6), and an eighth check valve (E8). One end of the auxiliary atomizing air path (E0) is connected to the compressed air source (E1), and the other end of the auxiliary atomizing air path (E0) is connected in sequence to the orifice plate (E2), the fifth shut-off valve (E5), the eighth flow sensor (E6) and the eighth check valve (E8) before being connected to the auxiliary atomizing air loop pipe (4-1H).

18. A gas turbine generator set according to claim 17, characterized in that: The liquid fuel purging system (C) includes a combustion chamber bleed air path (CD0), a liquid fuel purging path (C0-1), an atomized air purging path (C0-2), a fourth regulating valve (C4-1), a fifth regulating valve (C4-2), a fourth flow sensor (C6-1), a fifth flow sensor (C6-2), a fourth check valve (C8-1), and a fifth check valve (C8-2). The liquid fuel purge path (C0-1) and the atomizing air purge path (C0-2) are connected in parallel and share the combustion chamber bleed air path (CD0). The liquid fuel purge path (C0-1) is connected to the liquid fuel line (A0) after being connected in series with the fourth regulating valve (C4-1), the fourth flow sensor (C6-1), and the fourth check valve (C8-1). The atomizing air purge path (C0-2) is connected to the auxiliary atomizing air line (E0) after being connected in series with the fifth regulating valve (C4-2), the fifth flow sensor (C6-2), and the fifth check valve (C8-2).

19. A gas turbine generator set according to claim 18, characterized in that: The gaseous fuel purging system (D) includes the first branch purging path (D0-1) of the gaseous fuel flow path, the second branch purging path (D0-2) of the gaseous fuel flow path, the sixth regulating valve (D4-1), the seventh regulating valve (D4-2), the sixth flow sensor (D6-1), the seventh flow sensor (D6-2), the sixth check valve (D8-1), and the seventh check valve (D8-2). The first branch purge path (D0-1) and the second branch purge path (D0-2) of the gaseous fuel flow path are connected in parallel and share the combustion chamber bleed air path (CD0). The first branch purge path (D0-1) of the gaseous fuel flow path is connected to the first branch (B0-1) of the gaseous fuel flow path after being connected in series with the sixth regulating valve (D4-1), the sixth flow sensor (D6-1), and the sixth check valve (D8-1). The second branch purge path (D0-2) of the gaseous fuel flow path is connected to the second branch (B0-2) of the gaseous fuel flow path after being connected in series with the seventh regulating valve (D4-2), the seventh flow sensor (D6-2), and the seventh check valve (D8-2).

Images