Gas turbine power generation equipment, and device and method for drying gas turbine cooling air system
10352249 ยท 2019-07-16
Assignee
Inventors
Cpc classification
F02C7/30
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F02C3/107
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F05D2220/32
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F05D2260/232
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01D25/32
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F02C7/14
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F02C7/185
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F02C7/32
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F02C7/141
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F05D2260/211
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F05D2260/608
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
International classification
F02C7/30
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F02C3/107
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F02C7/14
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F02C7/141
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F02C7/18
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F02C7/32
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
Abstract
The occurrence of corrosion on the inner surfaces of pipes is to be minimized in a cooling air system of a gas turbine. Specifically, this gas turbine power generation equipment has: a gas turbine including a turbine connected to a generator, a combustor that supplies combustion gas to the turbine, and a compressor that supplies compressed air to the combustor; a cooling air system that supplies compressed air bled from the compressor to the turbine, the cooling air system being connected at a first end side to an intermediate stage or an outlet of the compressor and connected at a second end side to the turbine; and a drying air system that supplies drying air into the cooling air system when the gas turbine is stopped, the drying air system being connected to the cooling air system.
Claims
1. Gas turbine power generation equipment comprising: a gas turbine including a turbine connected to a generator, a combustor that supplies combustion gas to the turbine, and a compressor that supplies compressed air to the combustor; a cooling air system that supplies compressed air bled from the compressor to the turbine and passes the compressed air through a cooling hole of a turbine blade, the cooling air system being connected at a first end side to an intermediate stage or an outlet of the compressor and connected at a second end side to the turbine, the cooling air system including a heat exchanger that cools the compressed air bled from the compressor; a drying air system that supplies drying air into the cooling air system when the gas turbine is stopped, the drying air system being connected to the cooling air system; and a filter disposed between the heat exchanger of the cooling air system and the turbine, wherein the drying air system is connected to the cooling air system on a turbine side of the filter, and the drying air system has a first on-off valve, a second on-off valve, a drying air pipe connected therebetween, and a third on-off valve disposed on the drying air pipe.
2. The gas turbine power generation equipment according to claim 1, wherein in the drying air system, drying air is acquired from a control air supply system that supplies control air into the equipment.
3. The gas turbine power generation equipment according to claim 1, wherein in the drying air system, drying air is acquired from a control air supply system that supplies control air into the equipment.
4. A gas turbine cooling air system drying device that dries a cooling air system that supplies compressed air bled from a compressor via a heat exchanger on the route of the cooling air system to a turbine and passes the compressed air through a cooling hole of a turbine blade, the cooling air system connecting an intermediate stage or an outlet of the compressor to the turbine in a gas turbine, the gas turbine cooling air system drying device comprising: a drying air system that supplies drying air into the cooling air system, the drying air system being connected to the cooling air system; and a filter disposed between the heat exchanger of the cooling air system and the turbine, wherein the drying air system is connected to the cooling air system on a turbine side of the filter, and the drying air system has a first on-off valve, a second on-off valve, a drying air pipe connected therebetween, and a third on-off valve disposed on the drying air pipe.
5. A gas turbine cooling air system drying method for drying a cooling air system that supplies compressed air bled from a compressor via a heat exchanger on the route of the cooling air system to a turbine and passes the compressed air through a cooling hole of a turbine blade, the cooling air system connecting an intermediate stage or an outlet of the compressor to the turbine in a gas turbine, the method comprising: supplying drying air into the cooling air system when the gas turbine is stopped, wherein a filter is disposed between the heat exchanger of the cooling air system and the turbine, and the drying air system is connected to the cooling air system on a turbine side of the filter, and the drying air system has a first on-off valve, a second on-off valve, a drying air pipe connected therebetween, and a third on-off valve disposed on the drying air pipe.
6. The gas turbine cooling air system drying method according to claim 5, wherein the drying air is supplied on the turbine side of the heat exchanger.
Description
BRIEF DESCRIPTION OF DRAWINGS
(1)
(2)
(3)
(4)
DESCRIPTION OF EMBODIMENTS
(5) Detailed descriptions will be given below of embodiments according to the present invention on the basis of the drawings. Note that the present invention is not limited by these embodiments. In addition, the constituent elements in the embodiments described below include those that can be easily replaced by a person skilled in the art or those that are substantially the same.
(6)
(7) As illustrated in
(8) A drive shaft 101 of the generator 100 is connected to a turbine shaft 204 of the gas turbine 200 that is described later, and power is generated by applying the rotational power of the turbine shaft 204 to the drive shaft 101. Note that the generator 100 is also used as a start-up motor that applies rotational power to the turbine shaft 204 when the gas turbine 200 is started up.
(9) The gas turbine 200 has a compressor 201, a combustor 202, and a turbine 203. The turbine shaft 204 of the gas turbine 200 passes through the centers of the compressor 201, the combustor 202, and the turbine 203. The compressor 201, the combustor 202, and the turbine 203 are juxtaposed along an axis R of the turbine shaft 204 in that order from the front side towards the rear side of the flow of the air. Note that in the following description, the turbine axial direction refers to a direction parallel to the axis R, and the turbine circumferential direction refers to a circumferential direction about the axis R as the center.
(10) The compressor 201 generates compressed air by compressing air. As illustrated in
(11) As illustrated in
(12) As illustrated in
(13) The turbine shaft 204 is supported at the end on the compressor 201 side by a bearing 241, and is supported at the end on the exhaust chamber 234 side by a bearing 242, and is provided so that the turbine shaft 204 can freely rotate about the axis R as the center. Also, the turbine shaft 204 is connected to the drive shaft 101 of the generator 100 at the end thereof on the compressor 201 side.
(14) In the gas turbine 200, air taken in through the air inlet 211 of the compressor 201 passes through the plurality of compressor vanes 213 and compressor blades 214 and is compressed, thereby converting the air to high temperature high pressure compressed air. By mixing fuel and the compressed air in the combustor 202 and combusting the mixed fuel and compressed air, high temperature high pressure combustion gas is generated. Then, by passing the combustion gas through the turbine vanes 232 and the turbine blades 233 of the turbine 203, the turbine shaft 204 is driven in rotation, and rotational power is applied to the generator 100 connected to the turbine shaft 204 to generate electrical power. After driving the turbine shaft 204 in rotation, the exhaust gas passes through the exhaust diffuser 234a of the exhaust chamber 234 and is released to the atmosphere as exhaust gas.
(15) The cooling air system 300 is provided in the gas turbine 200, and supplies compressed air bled from the compressor 201 to the turbine 203.
(16) The following is a description of a configuration related to the cooling air system 300. As illustrated in
(17) Also, an intermediate shaft cover 253 formed in a ring shape along the turbine circumferential direction is fitted around the outer periphery of the turbine shaft 204, and on the outer periphery of the intermediate shaft cover 253, a turbine compartment 254 is demarcated within the combustor casing 224 on the outside of the plurality of combustors 202. On the other hand, the transition piece 222 of the combustor 202 is connected to a combustion gas passage 255 formed in a ring shape along the turbine circumferential direction in the turbine 203. The plurality of turbine vanes 232 and the plurality of turbine blades 233 (blade portions 233c) are disposed alternately along the turbine axial direction in the combustion gas passage 255.
(18) A cooling air supply hole 256 opening as an inlet on the compressor 201 side is provided along the turbine axial direction in the turbine disks 251 of the turbine shaft 204. The cooling air supply hole 256 is formed along the turbine axial direction, and is linked to a cooling hole (not illustrated on the drawings) provided within each turbine blade 233 via each turbine disk 251. Also, within the intermediate shaft cover 253, in the vicinity of the inlet to the cooling air supply hole 256, a seal ring retaining ring 257 is provided formed in a ring shape along the turbine circumferential direction. At each end in the turbine axial direction, the seal ring retaining ring 257 is fitted in close contact at the outer peripheral surface thereof with the inner periphery of the intermediate shaft cover 253, thereby partitioning a space 262 with the intermediate shaft cover 253, in the center in the turbine axial direction and along the turbine circumferential direction. Also, a plurality of seals 258, 259, 260, 261 that seal the gap between the inner peripheral surface of the seal ring retaining ring 257 and the outer peripheral surface of the turbine shaft 204 are provided on the inner peripheral surface side of the seal ring retaining ring 257. Also, the space 262 partitioned between the intermediate shaft cover 253 and the seal ring retaining ring 257 is linked to the inlet to the cooling air supply hole 256 via a through hole 263 formed in the seal ring retaining ring 257.
(19) A first end side of a cooling air pipe 301 of the cooling air system 300 is connected to the combustor casing 224 so that the turbine compartment 254 is linked to the outside thereof. Specifically, as illustrated in
(20) When the gas turbine 200 is operating, the compressed air that has been compressed by the compressor 201 of the gas turbine 200 is supplied to the turbine compartment 254. The compressed air is guided from the turbine compartment 254 to the combustor 202, and high temperature high pressure combustion gas is generated in the combustor 202, which passes through the transition piece 222 and flows through the combustion gas passage 255 and is fed to the turbine 203. In the cooling air system 300, a portion of the compressed air supplied to the turbine compartment 254 linked to the outlet of the compressor 201 is bled from the first end side of the cooling air pipe 301, and is supplied from the second end side of the cooling air pipe 301 through the space 262 and through the through hole 263 to the cooling air supply hole 256 on the turbine 203 side, and passes through a cooling hole in each turbine blade 233. The compressed air that passes through the cooling air pipe 301 is cooled by the TCA cooler 303, foreign matter is removed by the filter 304, and the compressed air is delivered to each turbine blade 233, where the compressed air cools each turbine blade 233.
(21) In this cooling air system 300, the cooling air pipe 301 is formed with a sufficient pipe cross-sectional area so that unnecessary pressure loss does not occur. Also, normally in the cooling air system 300 of the gas turbine 200, at the turbine compartment 254 on the compressor 201 side to which the first end side of the cooling air pipe 301 is connected, it is necessary that the bled compressed air be supplied without pressure loss to the turbine side. On the other hand, in the case of the cooling air supply hole 256 and the cooling holes of the turbine blades 233 on the turbine 203 side to which the second end side of the cooling air pipe 301 is connected, it is necessary that the quantity of air leaking from the seals and the like be reduced so that the cooled air is not unnecessarily consumed and the performance of the gas turbine is not reduced. Therefore, when the CdA values (product of the flow rate coefficient Cd and the area A of the flow passage) for the turbine compartment 254 at the first end side of the cooling air pipe 301 and for the cooling air supply hole 256 and the cooling holes of the turbine blades 233 at the second end side of the cooling air pipe 301 are compared, there is a relationship in which the CdA value at the turbine compartment 254 side is larger and the CdA value at the side of the cooling air supply hole 256 and the cooling holes of the turbine blade 233 is smaller.
(22) In the cooling air system 300 as described above, compressed air from the outlet of the compressor 201 is bled and supplied to the turbine 203 side, but the present invention can also be applied to other cooling air systems.
(23) In the gas turbine 200 as described above, as illustrated in
(24) As illustrated in
(25) Therefore, in the cooling air system 500, compressed air compressed by the compressor 201 of the gas turbine 200 is bled from the compressor air bleed chamber 215 to the first end of the cooling air pipe 501, and passes from the second end side of the cooling air pipe 501 through the turbine vane ring cavity 235 to cooling holes in each turbine vane 232. The compressed air that passes through the cooling air pipe 501 is cooled by the TCA cooler 503, foreign matter brought in from the compressor air bleed chamber 215 is removed by the filter 504, and the compressed air is delivered to each turbine vane 232, where the compressed air cools each turbine vane 232.
(26) In this cooling air system 500, the cooling air pipe 501 is formed with a sufficient pipe cross-sectional area so that unnecessary pressure loss does not occur. Also, normally in the cooling air system 500 of the gas turbine 200, at the compressor air bleed chamber 215 on the compressor 201 side to which the first end side of the cooling air pipe 501 is connected, it is necessary that the bled compressed air be supplied without pressure loss to the turbine side. On the other hand, in the case of the cooling holes of the turbine vanes 232 on the turbine 203 side to which the second end side of the cooling air pipe 501 is connected, it is necessary that the quantity of air leaking from the seals and the like be reduced so that the cooled air is not unnecessarily consumed and the performance of the gas turbine is not reduced. Therefore, when the CdA values (product of the flow rate coefficient Cd and the area A of the flow passage) for the compressor air bleed chamber 215 at the first end side of the cooling air pipe 501 and for the cooling holes of the turbine vanes 232 at the second end side of the cooling air pipe 501 are compared, there is a relationship in which the CdA value at the compressor air bleed chamber 215 side is larger and the CdA value at the side of the cooling holes of the turbine vanes 232 is smaller.
(27) The drying air system 400 is a gas turbine cooling air system drying device that supplies drying air into the cooling air system 300, 500. As illustrated in
(28) Also, as illustrated in
(29) The drying air pipe 402 of the drying air system 400 is connected to the cooling air pipe 301, 501, and is configured so that when necessary drying air can be supplied from the drying air supply source 401 to the cooling air system 300, 500. Therefore an on-off valve is provided on the drying air pipe 402. There may be one on-off valve, but for safety preferably there are a first on-off valve 403 and a second on-off valve 404 from the drying air supply source 401 side towards the cooling air system 300, 500. A blow pipe 402a that is open to the atmosphere is connected to the drying air pipe 402 between the first on-off valve 403 and the second on-off valve 404. The blow pipe 402a is opened and closed by a blow on-off valve 405.
(30) Also, the drying air system 400 is used when the gas turbine 200 is stopped (mainly when the turbine is stationary or turning). In other words, when the gas turbine 200 is stopped, the on-off valves, namely the first on-off valve 403 and the second on-off valve 404, are in the open state, and the blow on-off valve 405 is in the closed state. Then drying air is supplied to the cooling air pipe 301, 501 from the drying air supply source 401 via the drying air pipe 402. Therefore, the drying air is fed within the cooling air system 300, 500, and the inside of the cooling air system 300, 500 is dried. As a result, the occurrence of corrosion on the inner surfaces of the cooling air pipe 301, 501 of the cooling air system 300, 500 is minimized. Note that the timing of supply of the drying air to the cooling air system 300, 500 may be when three days have passed after the gas turbine 200 is stopped. If three or more days have passed after the gas turbine 200 has stopped, the air temperature within the cooling air pipe 301, 501 falls to the dew point or lower, so there is a high possibility that the moisture within the air will condense.
(31) Note that the drying air system 400 may be configured so that the drying air system 400 is automatically activated when the gas turbine 200 has been stopped or when three days have passed after the gas turbine 200 has been stopped. In this case the drying air system 400 includes a control device 406 that detects stopping and operation of the gas turbine 200, and controls the first on-off valve 403, the second on-off valve 404, and the blow on-off valve 405. In order to detect stoppage of the gas turbine 200, for example, the control device 406 is connected to a control device (not illustrated on the drawings) of the gas turbine 200. Also, the control device 406 is connected to the first on-off valve 403, the second on-off valve 404, and the blow on-off valve 405 in order to control the first on-off valve 403, the second on-off valve 404, and the blow on-off valve 405. Also, the control device 406 controls the first on-off valve 403, the second on-off valve 404, and the blow on-off valve 405 to be closed during operation of the gas turbine 200. Also, when the gas turbine 200 is stopped, the control device 406 controls the first on-off valve 403 and the second on-off valve 404 to be opened in that order with the blow on-off valve 405 controlled to remain closed. Also, when the gas turbine 200 is operating, if the first on-off valve 403 and the second on-off valve 404 are not in the closed state, the control device 406 controls the blow on-off valve 405 to be in the open state.
(32) In other words, the gas turbine power generation equipment 1 according to the present embodiment includes: the gas turbine 200 provided with the turbine 203 connected to the generator 100, the combustor 202 that supplies combustion gas to the turbine 203, and the compressor 201 that supplies compressed air to the combustor 202; the cooling air system 300, 500 that supplies compressed air bled from the compressor 201 to the turbine 203, the cooling air system 300, 500 being connected at the first end side to an intermediate stage or the outlet of the compressor 201 and connected at the second end side to the turbine 203; and the drying air system 400 that supplies drying air into the cooling air system 300, 500 when the gas turbine 200 is stopped, the drying air system 400 being connected to the cooling air system 300, 500.
(33) According to this gas turbine power generation equipment 1, by supplying drying air to the cooling air system 300, 500 when the gas turbine 200 is stopped, the inside of the cooling air system 300, 500 is dried. As a result, the occurrence of corrosion on the inner surfaces of the cooling air pipe 301, 501 of the cooling air system 300, 500 can be minimized.
(34) When the gas turbine 200 is stopped for a long period of time (for example, 30 days or more), a blowing operation for the cooling air system 300, 500 under no load of the gas turbine 200 can be considered with the object of discharging corrosion on the inner surfaces of the cooling air pipe 301, 501 of the cooling air system 300, 500, but this blowing operation consumes fuel not associated with power generation. According to the gas turbine power generation equipment 1 of the present embodiment, by supplying drying air to the cooling air system 300, 500 when the gas turbine 200 is stopped, the inside of the cooling air system 300, 500 is dried and the occurrence of corrosion is minimized, so it is not necessary to carry out the blow operation, and the quantity of fuel used can be reduced.
(35) Also, in the gas turbine power generation equipment 1 according to the present embodiment, the drying air system 400 is connected to the cooling air system 300, 500 at the second end side.
(36) In the cooling air system 300, the CdA value at the opening of the connection between the cooling air pipe 301 and the combustor casing 224, which is at the first end side of the cooling air pipe 301, is large, and the CdA value at the side of the cooling holes of the turbine blades 233 which is connected to the second end side of the cooling air pipe 301 is small, so the drying air mostly flows towards the combustor casing 224 side, which is the first end side of the cooling air pipe 301. Also, in the cooling air system 500, the CdA value at the compressor air bleed chamber 215 side, which is at the first end side of the cooling air pipe 501, is large, and the CdA value at the side of the cooling holes of the turbine vanes 232, which is connected to the second end side of the cooling air pipe 501, is small, so the drying air mostly flows towards the compressor air bleed chamber 215 side, which is the first end side of the cooling air pipe 501. Therefore, by connecting the drying air system 400 to the second end side of the cooling air system 300, 500 (preferably to the second end of the cooling air pipe 301, 501), as in the gas turbine power generation equipment 1 according to the present embodiment, the whole atmosphere of the cooling air system 300, 500 can be efficiently replaced with drying air, so a significant effect of reduction in the occurrence of corrosion on the inner surfaces of the cooling air pipe 301, 501 of the cooling air system 300, 500 can be obtained.
(37) Also, in the gas turbine power generation equipment 1 according to the present embodiment, the TCA cooler (heat exchanger) 303, 503 that cools the compressed air is provided on the route of the cooling air system 300, 500, and the drying air system 400 is connected to the cooling air system 300, 500 on the turbine 203 side of the TCA cooler 303, 503.
(38) In the cooling air system 300, the CdA value at the opening of the connection between the cooling air pipe 301 and the combustor casing 224, which is at the first end side of the cooling air pipe 301, is large, and the CdA value at the side of the cooling holes of the turbine blades 233, which is connected to the second end side of the cooling air pipe 301, is small, so the drying air mostly flows towards the combustor casing 224 side, which is the first end side of the cooling air pipe 301. Also, in the cooling air system 500, the CdA value at the compressor air bleed chamber 215 side, which is at the first end side of the cooling air pipe 501, is large, and the CdA value at the side of the cooling holes of the turbine vanes 232, which is connected to the second end side of the cooling air pipe 501, is small, so the drying air mostly flows towards the compressor air bleed chamber 215 side, which is the first end side of the cooling air pipe 501. Therefore, by connecting the drying air system 400 to the cooling air system 300, 500 on the turbine 203 side of the TCA cooler 303, 503, as in the gas turbine power generation equipment 1 according to the present embodiment, the whole atmosphere of the cooling air system 300, 500 can be efficiently replaced with drying air, so a significant effect of reduction in the occurrence of corrosion on the inner surfaces of the cooling air pipe 301, 501 of the cooling air system 300, 500 can be obtained. Moreover, according to the gas turbine power generation equipment 1, by connecting the drying air system 400 to the cooling air system 300, 500 on the turbine 203 side of the TCA cooler 303, 503, a greater quantity of drying air can flow to the TCA cooler 303, 503, and it is possible to rapidly reduce the humidity within the TCA cooler 303, 503, so the occurrence of corrosion within the TCA cooler 303, 503 can be reduced.
(39) Also, in general, when the TCA cooler 303, 503 is provided on the cooling air pipe 301, 501 of the gas turbine 200, the TCA cooler 303, 503 is commonly provided at a position about half the total pipe length of the cooling air pipe 301, 501. In this case, according to the gas turbine power generation equipment 1 of the present embodiment, the drying air system 400 is connected at a position on the turbine 203 side (the second end side) of the total pipe length of the cooling air pipe 301, 501, so drying air can be effectively delivered to the pipes on the compressor 201 side from a connection point that accounts for a large proportion of the total pipe length of the cooling air pipe 301, 501. Therefore, the occurrence of corrosion on the inner surfaces of the cooling air pipe 301, 501 can be effectively minimized.
(40) Also, in the gas turbine power generation equipment 1 according to the present embodiment, the filter 304, 504 is provided on the route of the cooling air system 300, 500 to remove foreign matter from the compressed air, and the drying air system 400 is connected to the cooling air system 300, 500 on the turbine 203 side of the filter 304, 504.
(41) As stated previously, most of the drying air flows towards the compressor air bleed chamber 215 side, which is the first end side of the cooling air pipe 501. Therefore, by connecting the drying air system 400 to the cooling air system 300, 500 on the turbine 203 side of the filter 304, 504, as in the gas turbine power generation equipment 1 according to the present embodiment, a greater quantity of drying air can flow through the whole of the cooling air system 300, 500, so a significant effect of reduction in the occurrence of corrosion on the inner surfaces of the cooling air pipe 301, 501 of the cooling air system 300, 500 can be obtained. Moreover, according to the gas turbine power generation equipment 1, a greater quantity of drying air can flow through the filter 304, 504, so the occurrence of corrosion in the filter 304, 504 can be reduced.
(42) Also, in the gas turbine power generation equipment 1 according to the present embodiment, the drying air system 400 obtains drying air from the control air supply system that supplies control air into the equipment.
(43) The control air supply system is a drive source for air operated valves disposed within the equipment, and generates dehumidified drying air. The demand for drying air from the control air supply system is small when the gas turbine 200 is stopped, so by using this drying air in the drying air system 400, the drying air that is used within the equipment can be effectively used without providing a new drying air supply source.
REFERENCE SIGNS LIST
(44) 1 Gas turbine power generation equipment 100 Generator 200 Gas turbine 201 Compressor 203 Turbine 300, 500 Cooling air system 301, 501 Cooling air pipe 303, 503 TCA cooler (heat exchanger) 400 Drying air system