JP2017138023A - Steam injection gas turbine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a steam injection gas turbine which can reduce NOx even at starting, and which can miniaturize a drain water treatment facility.SOLUTION: A steam injection gas turbine includes: a compressor for compressing air and generating high pressure combustion air; a combustor for generating a combustion gas by burning combustion air and a fuel; and a turbine driving with the combustion gas generated in the combustor. The steam injection gas turbine injects steam into the combustor. The combustor includes: a plurality of steam nozzles for jetting steam at a position further on the upstream side than a flame zone in the flow of the combustion air; steam headers communicating with the plurality of steam nozzles respectively; and a water spraying nozzle communicating with the lowermost part of the steam header. An outlet of the water spraying nozzle opens at the position further on the upstream side than the flame zone in the flow of the combustion air.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a steam injection gas turbine, and more particularly to a steam injection gas turbine that injects a part of steam generated from exhaust heat of a gas turbine into the gas turbine.

  As a method for reducing NOx exhausted from a gas turbine, a method of suppressing the generation of thermal NOx by generating steam with the thermal energy of exhaust gas from the gas turbine and lowering the flame temperature by injecting the generated steam into a combustor. There is. There is also a system for injecting generated steam into a combustor for the purpose of increasing the output of a gas turbine.

  Patent Document 1 includes two steam injection systems to the combustor, a first steam system that injects steam upstream of the flame zone with respect to the flow of combustion gas in the combustor, and a downstream side of the flame zone. A second steam system for injecting steam, controlling the steam flow rate of the first steam system according to the flow rate and composition of the fuel, and the steam flow rate of the second steam system according to the required steam flow rate required by the steam consuming equipment An invention of a steam-injection gas turbine for controlling the above is disclosed.

  In this steam injection gas turbine, the steam injection of the first steam system has the NOx reduction effect described above, and the steam injection of the second steam system has the effect of increasing the output. However, when such a steam injection gas turbine is started, steam may be condensed into drain water in a low-temperature steam piping system immediately after the start of steam injection. When this drain water is ejected from the steam injection nozzle into the flame, there is a possibility that the stability of combustion is impaired.

  Patent Document 2 discloses a control of a steam injection system in a combined cycle power plant that positively eliminates the drain generated in the steam injection piping system at the time of starting the power plant so that stable combustion operation characteristics can be obtained. For the purpose of providing a method and an apparatus therefor, prior to the start of the gas turbine apparatus, the steam piping system is warmed up by supplying steam from a separate auxiliary boiler, while drain water is supplied at the pressure of the auxiliary steam. An invention for discharging out of the system is disclosed.

JP 2014-173572 A Japanese Patent Publication No. 7-30585

  As described above, in the conventional steam injection gas turbine, when the method of discharging the generated drain water outside the system is adopted, the injected steam is drained until the warm-up of the steam injection system is completed. And discharged. This reduces the low NOx effect because no steam is supplied to the flame zone. Another problem is that a separate facility for treating the discharged drain water is required.

  The present invention has been made based on the above-described matters, and an object of the present invention is to provide a steam injection gas turbine that can reduce NOx even at the time of start-up and can reduce the size of the drain water treatment facility.

  In order to solve the above problems, for example, the configuration described in the claims is adopted. The present application includes a plurality of means for solving the above-described problems. For example, a compressor that compresses air to generate high-pressure combustion air, and combusts the combustion air and fuel. A combustor that generates combustion gas, and a turbine that is driven by the combustion gas generated by the combustor, and a steam injection gas turbine that injects steam into the combustor, wherein the combustor is used for the combustion A plurality of steam nozzles that inject steam to a position upstream of the flame zone in the flow of air; a steam header that communicates with each of the plurality of steam nozzles; and a water spray nozzle that communicates with a lowermost portion of the steam header; The outlet of the water spray nozzle is opened at a position upstream of the flame zone in the combustion air flow.

  According to the present invention, since the atomization of high-temperature drain water is promoted at the time of starting the steam injection gas turbine, it is possible to achieve a low NOx while maintaining the stability of combustion. In addition, the drain water treatment facility can be reduced in size.

It is a system flow figure showing an example of the whole composition of the thermoelectric variable type cogeneration system using a 1st embodiment of the steam injection gas turbine of the present invention. It is a system flowchart which shows the structure of the other example which provided multiple water spray nozzles in 1st Embodiment of the steam injection gas turbine of this invention. It is a system flowchart which shows the structure of the further another example from which the ejection position of the water spray nozzle differs in 1st Embodiment of the steam injection gas turbine of this invention. It is a system flow figure showing an example of composition of a 2nd embodiment of a steam injection gas turbine of the present invention. It is a system flow figure showing an example of composition of a 3rd embodiment of a steam injection gas turbine of the present invention. It is a system flowchart which shows the structure of the other example which provided a part of drain water communication pipe | tube and filter in the 3rd Embodiment of the steam injection gas turbine of this invention outside the combustor outer cylinder. A part of the drain water communication pipe and the filter in the third embodiment of the steam injection gas turbine of the present invention and a filter are provided outside the combustor outer cylinder, and a configuration of still another example in which the spray position of the water spray nozzle is different is shown. It is a system flow figure.

  Embodiments of the steam injection gas turbine of the present invention will be described below with reference to the drawings.

  FIG. 1 is a system flow diagram showing an example of the overall configuration of a thermoelectrically variable cogeneration system using the first embodiment of the steam injection gas turbine of the present invention. As shown in FIG. 1, the thermoelectric variable cogeneration system mainly includes a steam injection gas turbine 4, an exhaust heat recovery boiler 5, and a steam system 300.

  The steam injection gas turbine 4 mainly includes a compressor 1 that compresses air 100 to generate high-pressure combustion air 101, and compressed air 101 introduced from the compressor 1 and fuel 201 from the fuel system 200. A plurality of combustors 2 that combust and generate combustion gas 106, and a turbine 3 into which the combustion gas 106 generated by the combustor 2 is introduced.

  The turbine 3 is divided into a gas generator turbine 3a and a power turbine 3b. The gas generator turbine 3a is connected to the compressor 1 by a shaft 21a and drives the compressor 1. On the other hand, the power turbine 3b is connected to the generator 20 by the shaft 21b and drives the generator 20.

  The combustor 2 is stored in an internal space constituted by a combustor outer cylinder 7 and a combustor cover 8 provided at an end of the combustor outer cylinder 7. The combustor outer cylinder 7 is attached to the turbine casing 23. A fuel nozzle 9 is disposed at the center of the upstream end of the combustor 2, and a substantially cylindrical combustor liner 10 that separates unburned air and burned combustion gas is disposed downstream thereof. A liner flow sleeve 11 is provided on the outer peripheral side of the combustor liner 10. The liner flow sleeve 11 has a substantially cylindrical shape and is fastened to the combustor outer cylinder 7 so as to be substantially coaxial with the combustor liner 10.

  A tail cylinder 12 that guides combustion gas to the turbine 3 is provided downstream of the combustor liner 10. The outer peripheral side of the downstream end of the combustor liner 10 is connected so as to be inserted into the inner peripheral side of the upstream end of the transition piece 12. A tail tube flow sleeve 13 is provided on the outer peripheral side of the tail tube 12. The outer peripheral side of the downstream end of the liner flow sleeve 11 is connected by being inserted into the inner peripheral side of the upstream end of the transition piece flow sleeve 13.

  The high-pressure compressed air 101 that has come out of the compressor 1 flows from the space in the turbine casing 23 into the space between the transition piece 12 and the transition piece flow sleeve 13 from the opening on the turbine side that is the downstream side. The compressed air 101 cools the tail cylinder 12 from the outside when flowing to the combustor liner 10 side, which is the upstream side. Thereafter, the compressed air 101 flows toward the upstream side of the combustor 2 through a generally annular space between the combustor liner 10 and the liner flow sleeve 11. At that time, the combustor liner 10 is cooled from the outside.

  Further, a part of the compressed air 101 flows into the combustor liner 10 from the cooling holes provided in the combustor liner 10 as liner cooling air 102 and is used for film cooling. Another part of the air flows as dilution air 103 into the combustor liner 10 through a plurality of dilution holes 14 provided in the combustor liner 10, and mixes with the combustion gas 105 into the tail cylinder 12. Inflow.

  Further, another part of the air flows into the combustor liner 10 from the plurality of combustion holes 30 provided in the combustor liner 10 as secondary combustion air 110, together with the fuel that could not be combusted by the combustion air 104. Used for secondary combustion.

  Further, the remaining air flows into the combustor liner 10 from the air swirler 17 provided on the outer periphery of the fuel nozzle 9 as the combustion air 104 and is used for combustion together with the fuel ejected from the fuel nozzle 9. Here, when the fuel flow rate is large, all of the ejected fuel cannot be combusted with the supplied amount of combustion air 104. Unburned fuel moves to the downstream side and burns with the secondary combustion air 110 described above on the downstream side.

  By this combustion, a high-temperature combustion gas 105 is generated, and further mixed with the cooling air 102 and the dilution air 103 to become the combustion gas 106 and sent to the turbine 3. The combustion gas 106 is sent to the power turbine 3b as the gas generator exhaust gas 107 after driving the gas generator turbine 3a of the turbine 3. The gas turbine exhaust gas 108 exiting the power turbine 3 b is exhausted as exhaust gas 109 after heat recovery by the exhaust heat recovery boiler 5.

  The fuel system 200 of the gas turbine is provided with a fuel flow rate adjusting valve 202 and a fuel flow meter 203 for detecting the flow rate of the fuel 201, and the power generation output of the steam injection gas turbine 4 is adjusted by adjusting the fuel flow rate. it can.

Next, the steam system 300 will be described.
The exhaust heat recovery boiler 5 includes a feed water heater 24, a boiler 25, and a steam superheater 26, and the generated steam is mainly consumed by the steam consumption facility 6 through the steam supply system 300A. The steam consuming equipment 6 may be equipment that requires a heat source such as a factory. The piping of the steam supply system 303 for supplying steam to the steam consuming facility 6 is provided with an air supply steam flow rate adjustment valve 313 to control the amount of supplied steam. A steam pressure gauge 305 that detects the pressure of steam generated from the exhaust heat recovery boiler 5 is provided in the main pipe from the exhaust heat recovery boiler 5.

  Further, a steam discharge system 304 is provided in order to discharge the steam generated in the exhaust heat recovery boiler 5 to the atmosphere as necessary. A steam release valve 314 is provided in the piping of the steam release system 304 to control the amount of released steam.

  On the other hand, when the amount of steam generated in the exhaust heat recovery boiler 5 exceeds the amount of steam necessary for the steam consuming equipment 6, surplus steam can be injected into the steam injection gas turbine 4. In the present embodiment, steam is injected into the combustor 2. In this way, the thermoelectric variable cogeneration system makes the thermoelectric ratio variable by injecting surplus steam into the steam injection gas turbine 4 and increasing the output of the generator 20.

  In the first embodiment of the steam injection gas turbine of the present invention, this injection steam system is divided into two systems, a first steam system 301 and a second steam system 302. Further, each system is provided with a first steam flow rate adjustment valve 311 and a second steam flow rate adjustment valve 312 so that each flow rate can be adjusted.

  The first steam system 301 includes a steam pipe 321 having one end connected to the steam supply system 300 </ b> A and the other end connected to a steam flange 351 provided on the combustor cover 8. The first steam system 301 includes a first steam in the steam pipe 321. A flow control valve 311 is provided. The first steam 331 passing through the inside of the first steam system 301 is injected into the combustor 2 from a steam nozzle 352 provided in the combustor cover 8.

  A substantially annular steam header 350 is provided inside the combustor cover 8 and communicates with the steam pipe 321 through a steam flange 351. A plurality of steam nozzles 352 are attached to the combustor liner 10 side of the steam header 350. Further, one end side of a drain water communication pipe 353 communicating with the steam header 350 is connected to the lowermost part of the steam header 350, and a water spray nozzle 354 is attached to a tip portion that is the other end side. The water spray nozzle 354 opens toward the annular space between the combustor liner 10 and the liner flow sleeve 11. The lowermost part in the description of the present embodiment is the lowermost part in the direction of gravity in each combustor 2, and the lowermost part of the annular steam header 350 is also the lowermost part in the direction of gravity. Show.

  The injection position of the first steam 331 is upstream of the flame zone with respect to the flow of the combustion gas 105, and is a position where most of the injected steam is mixed with the combustion air 104 or the fuel 201. More specifically, the fuel is injected into a space outside the combustor liner 10 and surrounded by the combustor outer cylinder 7, the combustor cover 8, and the combustor liner 10.

  The combustion air 104 at this position is the air after the high-pressure compressed air 101 branches off from the liner cooling air 102 and the dilution air 103, and most of it is consumed for combustion with fuel. The first steam 331 mixed in the above has a great effect of lowering the temperature of the flame zone, and has a large degree of contribution to reducing NOx.

  The second steam system 302 includes a steam pipe 322 having one end connected to the steam supply system 300 </ b> A and the other end connected to the steam injection port 15 provided in the combustor outer cylinder 7. A two steam flow rate control valve 312 is provided. The second steam 332 passing through the inside of the second steam system 302 first flows in a substantially annular space between the combustor outer cylinder 7 and the liner flow through-being 11. This space and the space in the turbine casing 23 are separated by a partition wall 18. As a result, mixing of the second steam 332 that has flowed into the combustor 2 and the compressed air in the turbine casing 23 is suppressed.

  Further, the second steam 332 flows in the entire circumferential direction on the outer peripheral side of the liner flow sleeve 11. For this reason, even if there is only one steam port 15 for one of the combustor outer cylinders 7, it is possible to make the moisture content uniform in the circumferential direction of the combustor 2.

  The liner flow sleeve 11 is provided with a plurality of steam injection holes 16 in the circumferential direction. All or part of these steam injection holes 16 are opposed to all or part of the dilution holes 14 provided in the combustor liner 10.

  Most of the second steam 332 that has passed through the steam injection hole 16 provided at a position facing the dilution hole 14 flows into the combustor liner 10 through the dilution hole 14. Therefore, most of the second steam 332 is mixed with the combustion gas 105 after combustion on the downstream side of the flame zone with respect to the flow of the combustion gas 105.

  Since the injected steam is mixed with the combustion gas 105 and the diluted air 103 after combustion, there is no direct influence on the flame zone. Accordingly, it is possible to increase the output by injecting surplus steam into the combustor 2 without affecting the stability of combustion. Further, since this injection position is upstream of the turbine 3, the energy of the steam can be effectively converted into power by the turbine 3.

  Further, since the combustion gas 105 is mixed with steam when flowing into the turbine 3 and the temperature is lowered, the metal temperature of the tail cylinder 12 and the turbine 3 can be lowered if the output is the same. Improve the life and prolong the life. Moreover, the fuel flow rate for the vapor mixture can be increased. For this reason, at the same turbine inflow temperature, the output and efficiency can be improved by the amount of steam mixed.

  Next, the flow of steam when starting the steam injection gas turbine will be described. When the steam injection gas turbine 4 is started and the gas turbine exhaust gas 108 is sent to the exhaust heat recovery boiler 5, steam starts to be generated from the exhaust heat recovery boiler 5. Then, when the pressure of the steam supply system 300 </ b> A detected by the steam pressure gauge 305 becomes larger than a predetermined pressure, the first steam flow rate adjustment valve 311 of the first steam system 301 is opened to supply the combustor 2 to the combustor 2. Start steam injection. The first steam 331 flows through the steam pipe 321. The first steam 331 is supplied from the steam pipe 321 through the steam flange 351 to the steam header 350 in the combustor cover 8 and fills the steam header 350. Then, it is ejected from the steam nozzle 352 into the combustor 2 and mixed with the combustion air 104 to be used for combustion. By mixing the steam with the combustion air 104, the local temperature of the flame zone is lowered, and the generated NOx can be reduced.

  On the other hand, since the temperature of the combustor cover 8 is low when the steam injection gas turbine is started, the heat of the steam is taken away by the steam header 350 into which the first steam 331 flows, and a part of the steam is drained inside. become. The generated drain water accumulates at the lowermost part of the steam header, flows in the drain water communication pipe 353 due to the pressure of the steam, becomes fine water droplets from the water spray nozzle 354, and is annular between the combustor liner 10 and the liner flow sleeve 11. Erupts into space. The drain water evaporates in the process of mixing with the combustion air 104 flowing through the annular space, and lowers the flame temperature when used for combustion inside the combustor liner 10. This demonstrates the effect of NOx suppression.

  Unlike the steam nozzle 352, the water spray nozzle 354 can spray water as fine water droplets. For this reason, compared with the case where drain water is ejected from the steam nozzle 352, evaporation is accelerated, so that the possibility that the drain water reaches the flame while being in a liquid state and impairs combustion stability can be reduced.

  In addition, in order to reduce NOx at the time of startup, for example, compared to a case where boiler feed water or the like is sprayed separately, drain water is high in temperature and thus is easily atomized, and low NOx is achieved while ensuring combustion stability. Suitable for

  Compared with the treatment after discharging hot drain water out of the system, the equipment for treating the high temperature water can be reduced, and the fuel energy of the drain water can be used internally, thus saving energy. It also becomes.

  FIG. 2 is a system flow diagram showing a configuration of another example in which a plurality of water spray nozzles are provided in the first embodiment of the steam injection gas turbine of the present invention. In the present embodiment, the case where one water spray nozzle 354 is provided as shown in FIG. 1 is described as an example, but the present invention is not limited to this. As shown in FIG. 2, a substantially annular drain water header 355 is disposed on the outer periphery of the liner flow sleeve 11, a plurality of water spray nozzles 354 are attached to the drain water header 355, and droplets are applied to the outer periphery of the combustor liner 10. You may spray.

  Compared with the case where water droplets are sprayed from one place as shown in FIG. 1, water droplets can be sprayed more uniformly in the circumferential direction of the combustor 2, so the low NOx effect can be further improved. Furthermore, since moisture in the combustion air is not biased in the circumferential direction, it is possible to prevent the combustion from becoming unstable, such as the occurrence of local flame extinction.

  FIG. 3 is a system flow diagram showing the configuration of still another example in which the spray position of the water spray nozzle is different in the first embodiment of the steam injection gas turbine of the present invention. As shown in FIG. 3, the water spray nozzle 354 is arranged on the outer peripheral side of the transition piece flow sleeve 13 so as to spray water droplets on the annular air flow path between the transition piece 12 and the transition piece flow sleeve 13. May be.

  Compared to the case of FIG. 1, the distance from the spray position of the water spray nozzle to the flame becomes longer, so that the water droplets easily evaporate and the stability of the flame is improved. Further, since a part of the sprayed drain water flows into the combustor liner 10 together with the diluted air 103 through the dilution hole 14 and does not pass through the flame zone, even when a large amount of drain water is generated, The flame can be prevented from extinguishing.

  According to the first embodiment of the steam injection gas turbine of the present invention described above, since the atomization of high-temperature drain water is promoted when the steam injection gas turbine 4 is started, the combustion stability is kept low. NOx conversion can be achieved. In addition, the drain water treatment facility can be reduced in size.

  Hereinafter, a second embodiment of the steam injection gas turbine of the present invention will be described with reference to the drawings. FIG. 4 is a system flow diagram showing an example of the configuration of the second embodiment of the steam injection gas turbine of the present invention. In FIG. 4, the same reference numerals as those shown in FIGS. 1 to 3 are the same parts, and detailed description thereof is omitted.

  The second embodiment of the steam injection gas turbine according to the present invention shown in FIG. 4 is configured with the same equipment as the first embodiment, but the following configuration is different. In the present embodiment, the drain water communication pipe 353 is allowed to pass drain water from the steam header 350 side, but is provided with a check valve 356 that prevents passage of drain water from the water spray nozzle 354 side. Different.

  When the steam injection gas turbine 4 is started, when the first steam flow rate adjustment valve 311 of the first steam system 301 is opened to start steam injection into the combustor 2, the first steam 331 becomes a steam header 350. To fill in. And some steam turns into drain water inside. The generated drain water collects at the bottom of the steam header. When steam further flows into the steam header 350 and the pressure increases, the check valve 356 is opened and the accumulated drain water is pushed out and ejected as fine water droplets from the water spray nozzle 354. Alternatively, when the amount of drain water becomes large, the check valve 356 is opened due to the water head pressure difference, and the drain water is pushed out and ejected as fine water droplets from the water spray nozzle 354.

  By appropriately setting the operating pressure difference of the check valve 356, the drain water ejection flow rate can be maintained at a certain value or more. Thus, drain water can be mixed into the combustion air 104 without impairing water droplet refinement. As a result, flame stability can be maintained, and NOx reduction can be achieved more effectively.

  According to the second embodiment of the steam injection gas turbine of the present invention described above, the same effects as those of the first embodiment described above can be obtained.

  In addition, according to the second embodiment of the steam injection gas turbine of the present invention described above, the check valve 356 is provided in the drain water communication pipe 353, so that the discharge flow rate of the drain water can be maintained at a certain value or more. . Thus, drain water can be mixed into the combustion air 104 without impairing water droplet refinement, so that the stability of the flame can be maintained and NOx reduction can be achieved more effectively.

  Hereinafter, a third embodiment of the steam injection gas turbine of the present invention will be described with reference to the drawings. FIG. 5 is a system flow diagram showing an example of the configuration of the third embodiment of the steam injection gas turbine of the present invention. In FIG. 5, the same reference numerals as those shown in FIGS. 1 to 4 are the same parts, and detailed description thereof is omitted.

  Although the third embodiment of the steam injection gas turbine of the present invention shown in FIG. 5 is configured with almost the same equipment as the first embodiment, the following configuration is different. The present embodiment is different in that a filter 357 for preventing the passage of foreign substances is provided inside the drain water communication pipe 353.

  The drain water collected inside the steam header 350 may contain, for example, rusted powder that has rusted in the steam header 350. When such rust powder flows into the water spray nozzle 354, the flow path of the water spray nozzle 354 is partially blocked, and there is a possibility that the atomization of the drain water will not be performed satisfactorily. Further, when the foreign matter wears the flow path of the water spray nozzle 354 and changes the flow path shape, it similarly adversely affects normal atomization.

  When such an event occurs, the evaporation of drain water is delayed, water drops flow into the flame, and combustion may become unstable. In the unlikely event that the water spray nozzle 354 is completely blocked, drain water may be ejected from the steam nozzle 352. By installing the filter 357 in the drain water communication pipe 353, foreign matter in the drain water can be removed and normal atomization of the drain water can be maintained. As a result, flame stability can be ensured and NOx reduction can be achieved more effectively.

  FIG. 6 is a system flow diagram showing a configuration of another example in which a part of the drain water communication pipe and a filter are provided outside the combustor outer cylinder in the third embodiment of the steam injection gas turbine of the present invention. As shown in FIG. 6, a part of the drain water communication pipe 353 and the filter 357 may be disposed outside the combustor outer cylinder 7.

  Compared to the case of FIG. 5, the filter 357 can be easily cleaned and replaced, and foreign matter removal in the drain water and normal atomization of the drain water can be easily performed. As a result, flame stability can be maintained and NOx reduction can be effectively achieved more simply.

  In addition, there is an advantage that the degree of freedom of the number, size, direction, and the like of the devices to be attached to the drain water communication pipe 353 is increased, for example, the check valve 356 of the second embodiment is provided together with the filter 357.

  Further, there is an advantage that the degree of freedom in the direction in which the drain water communication pipe 353 is communicated with the steam header 350 is increased. As shown in FIG. 1, when the drain water communication pipe 353 is disposed inside the combustor outer cylinder 7, the communication direction of the drain water communication pipe 353 with respect to the steam header 350 is limited to the internal direction (the rightward direction in FIG. 1). It is done. In contrast, in the case of the configuration shown in FIG. 6, options such as downward and leftward spread, and members around the drain water communication pipe 353 (for example, the steam nozzle 352, the Ryan flow sleeve 11, the combustor outer cylinder 7, The drain water communication pipe can be installed at a position and a direction in which the drain water easily collects in the steam header 350 by avoiding other bolts (not shown).

  FIG. 7 shows still another example in which a part of the drain water communication pipe and the filter in the third embodiment of the steam injection gas turbine of the present invention are provided outside the combustor outer cylinder, and the spray position of the water spray nozzle is different. It is a system flow figure showing composition. As shown in FIG. 7, the degree of freedom for selecting the spray position of the water spray nozzle 354 is increased, and the position where the drain water can be sprayed in the space inside the turbine casing 23 and outside the transition piece flow sleeve 13. A water spray nozzle 354 may be disposed.

  When the vapor | steam which drain water evaporated mixes with the compressed air 101 of this position, moisture will be added to the air which convectively cools the tail cylinder 12 from the outside, flow volume and a heat capacity will increase, and cooling of the tail cylinder 12 will be carried out. Is promoted. Thereby, when the combustion gas temperature in the transition piece 12 is the same, the metal temperature of the transition piece 12 is lowered, and the life of the transition piece 12 can be extended. Further, when the metal temperature is the same, the combustion gas temperature can be raised, so that the output and efficiency of the steam injection gas turbine 4 can be improved.

  According to the third embodiment of the steam injection gas turbine of the present invention described above, the same effect as that of the first embodiment described above can be obtained.

  Further, according to the third embodiment of the steam injection gas turbine of the present invention described above, since the drain water communication pipe 353 is provided with the filter 357, the foreign matter in the drain water is removed and the drain water is normally atomized. Can be maintained. As a result, flame stability can be ensured and NOx reduction can be achieved more effectively.

  In each of the embodiments of the present invention described above, the steam header 350 formed in the combustor cover 8 in an annular shape has been described as an example, but the present invention is not limited to this. You may arrange | position to the outer side and the outer periphery of the combustor outer cylinder 7, and you may form a chamber inside the combustor 2 and make it communicate from the outside of a flange. Further, the shape may not be annular.

  The present invention is not limited to the above-described first to third embodiments, and includes various modifications. The above-described embodiment has been described in detail for easy understanding of the present invention, and is not necessarily limited to the one having all the configurations described.

1: compressor, 2: combustor, 3: turbine, 4: steam injection gas turbine, 5: exhaust heat recovery boiler, 6: steam consuming equipment, 7: combustor casing, 8: combustor cover, 9: fuel Nozzle, 10: combustor liner, 11: liner flow sleeve, 12: tail tube, 13: tail tube flow sleeve, 14: dilution hole, 15: steam injection port, 16: steam injection hole, 17: air swirler, 18 : Partition wall, 20: generator, 23: turbine casing, 100: air (atmospheric pressure), 101: compressed air, 102: liner cooling air, 103: dilution air, 104: combustion air, 105: combustion gas, 106: combustion Gas: 107: Gas generator exhaust gas, 108: Gas turbine exhaust gas, 109: Exhaust gas, 110: Secondary combustion air, 200: Fuel system, 201: Fuel, 202: Fuel flow control valve, 203: Flow meter, 300: steam system, 301: first steam system, 302: second steam system, 303: steam supply system, 304: steam discharge system, 311: first steam flow control valve, 312: first 2 steam flow rate control valve, 313: steam flow rate control valve for air supply, 314: steam release valve, 331: first steam, 332: second steam, 350: steam header, 351: steam flange, 352: steam nozzle 353: Drain water communication pipe, 354: Water spray nozzle, 355: Drain water header, 356: Check valve, 357: Filter

Claims (7)

A compressor that compresses air to produce high-pressure combustion air;
A combustor for combusting the combustion air and fuel to generate combustion gas;
A turbine driven by combustion gas generated in the combustor, and a steam injection gas turbine for injecting steam into the combustor,
The combustor includes a plurality of steam nozzles that inject steam to a position upstream of a flame zone in the combustion air flow;
A steam header in communication with each of the plurality of steam nozzles;
A water spray nozzle communicating with the lowermost portion of the steam header;
The outlet of the water spray nozzle opens at a position upstream of the flame zone in the flow of combustion air. The steam injected gas turbine according to claim 1.
The combustor includes a combustor outer cylinder formed in a substantially cylindrical structure, a combustor cover provided at an end of the combustor outer cylinder, uncombusted air and existing air inside the combustor outer cylinder. A substantially cylindrical combustor liner that separates combustion combustion gas, and a flow sleeve that is disposed on the outer peripheral side of the combustor liner and forms an annular space between the inner peripheral surface and the outer peripheral surface of the combustor liner. Prepared,
The steam injection gas turbine, wherein the steam header is annularly formed inside the combustor cover. The steam injection gas turbine according to claim 2,
An outlet of the water spray nozzle opens toward an annular space between the combustor liner and the flow sleeve. The steam injection gas turbine according to claim 3.
A steam injection gas turbine characterized in that a plurality of the water spray nozzles are provided in the circumferential direction of the outer periphery of the flow sleeve. The steam injection gas turbine according to claim 3.
A communication pipe that communicates the lowermost part of the steam header and the water spray nozzle;
A steam injection gas turbine, wherein the communication pipe is provided with a check valve that permits passage of drain water from the steam header and prevents passage of drain water from the water spray nozzle. The steam injection gas turbine according to claim 3.
A communication pipe that communicates the lowermost part of the steam header and the water spray nozzle;
A steam injection gas turbine characterized in that a filter for preventing passage of foreign substances is provided inside the communication pipe. The steam injected gas turbine according to claim 6.
A steam injection gas turbine, wherein a part of the communication pipe and the filter are arranged outside the combustor.

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