JP2745352B2 - Gas turbine engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to Antofagasta with a catalytic combustor burning by contacting a mixture of fuel and air to the catalytic
Engine .

[0002]

Also harmful nitrogen oxides (hereinafter referred to as NO _X) is generated in the exhaust gas in a gas turbine engine like the reciprocating engine, increases as the combustion temperature of the emissions mixture of NO _X is high I do. In a conventional gas turbine engine combustor, the combustion temperature of the air-fuel mixture reaches an extremely high temperature (for example, 2000 ° C.), so that it has been difficult to reduce the amount of NO _X emissions. Therefore, a so-called catalytic combustion type combustor has been proposed, in which a mixture provided in contact with a catalyst provided inside the combustor is burned. According to the catalytic combustion method, since the combustion of the mixture in the combustor is relatively carried out at low temperatures, it is possible to significantly reduce the NO _X in the exhaust gas.

[0003] Incidentally, the above-mentioned catalyst does not function unless its temperature becomes higher than a predetermined catalyst activation temperature (usually about 400 ° C to 500 ° C). It is necessary to raise the temperature of the catalyst or the mixture in contact with the catalyst by some method to a temperature equal to or higher than the catalyst activation temperature. for that reason,
It is known that a preheater is provided upstream of the catalyst carrier when the gas turbine engine is started to preheat the temperature of the air-fuel mixture supplied to the catalyst carrier to a temperature above the catalyst activation temperature (for example, Japanese Patent Publication No. 3-36139). Reference).

[0004]

However, the combustion efficiency of the air-fuel mixture cannot be sufficiently increased only by providing the preheater upstream of the catalyst supporting portion.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has a catalytic combustor provided with a preheater upstream of a catalyst carrier.
It is an object of the present invention to further improve the combustion efficiency of an air-fuel mixture in a gas turbine engine with a gas turbine .

[0006]

In order to achieve the above object, the present invention provides a compressor for compressing intake air,
A high-pressure turbine for driving this compressor and a fuel
Of air and high-pressure air supplied from the compressor
The high-pressure turbine drive
A catalytic combustor for generating working combustion gas;
The heat of the exhaust gas discharged from the
Preheat high-pressure air from the reservoir to the catalytic combustor
At least a heat exchanger for the catalyst combustor.
Gas on the upstream side of the catalyst supporting portion for supporting the catalyst.
An electric preheater capable of heating the high-pressure air when the turbine engine is started is provided, and fuel is supplied downstream of the preheater.

Further, the present invention provides, in addition to the first feature described above,
A second feature is that a catalyst heater is provided in at least a part of the catalyst supporting portion.

Further, the present invention provides, in addition to the second feature described above,
A third feature is that fuel is sprayed from downstream of the preheater toward the catalyst heater.

The present invention also provides a compressor for compressing intake air.
Presser and high-pressure tap to drive this compressor.
And the high pressure supplied from the fuel and the compressor
Higher by burning air-fuel mixture in contact with catalyst
Catalytic combustor generating combustion gas for pressure turbine drive
And heat of exhaust gas discharged from the high-pressure turbine.
High pressure from the compressor to the catalytic combustor
At least a heat exchanger for preheating air.
A fuel supply unit for supplying fuel upstream of a catalyst holding unit that holds the catalyst;
Upstream of the fuel supply means and downstream of the fuel supply means,
The fuel supplied from the fuel supply means when the bin engine is started
A fourth feature is that an electric preheater capable of promoting the evaporation of the fuel is provided , and the preheater has a honeycomb structure to have a function of rectifying the air-fuel mixture.

[0010] The present invention, in addition to the fourth feature described above,
A fifth feature is that the fuel supply means sprays fuel from upstream of the preheater toward the preheater.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

1 to 5 show a first embodiment of the present invention. FIG. 1 is a longitudinal sectional view of a gas turbine engine, FIG. 2 is a sectional view taken along line 2-2 of FIG. 1, and FIG. Main part enlarged sectional view of
4 is an enlarged sectional view taken along line 4-4 of FIG. 3, and FIG. 5 is a sectional view taken along line 5-5 of FIG.
It is a line expanded sectional view.

As shown in FIGS. 1 and 2, a two-shaft gas turbine engine G includes a cylindrical outer casing 1 having a bottom and an annular heat exchanger housing 2 connected to a rear opening of the outer casing 1. And an exhaust housing 3 that covers the rear part of the heat exchanger housing 2. An intake passage 6 having an air cleaner 4 and a silencer 5 is connected to a front portion of the outer casing 1, and a speed reducer box 7 is provided at the center of the exhaust housing 3, and a lower portion of the exhaust housing 3 is provided. The exhaust duct 8 is connected.

A centrifugal compressor 9 for compressing the air sucked from the intake passage 6 and a centrifugal high-pressure turbine 10 for driving the compressor 9 are disposed before and after a central opening formed in the outer casing 1. An axial flow low-pressure turbine 11 for taking out output is disposed behind the combustion chamber, and a combustion gas for driving the high-pressure turbine 10 and the low-pressure turbine 11 is provided in an upper space of the outer casing 1. A generating catalytic combustor 12 is provided. A cylindrical combustor housing 41 is fixed to the outer casing 1 so as to penetrate therethrough (see FIG. 2), and the catalytic combustor 12 is detachably mounted from the outside of the outer casing 1 via the combustor housing 41. . Inside the heat exchanger housing 2, the two turbines 10,
An annular heat exchanger 13 for recovering the heat energy of the exhaust gas passing through 11 and heating the intake air is provided so as to surround the speed reducer box 7 around its outer periphery. Is provided with a planetary gear type reducer 14 for reducing the output of the low-pressure turbine 11 and taking it out.

A high-pressure turbine shaft 16 is rotatably supported at the center of a compressor casing 15 provided in the outer casing 1, and a compressor rotor 17 having a number of blades formed on the outer periphery is fixed to the high-pressure turbine shaft 16. You. The air drawn into the compressor casing 15 from the intake passage 6 is compressed by the compressor rotor 17 and is supplied rearward through a radial air passage 19 formed between the outer casing 1 and the inner casing 18. . The front end of the high-pressure turbine shaft 16 is connected to auxiliary equipment such as a generator and a starter housed in an auxiliary equipment housing (not shown).

At the rear end of the high-pressure turbine shaft 16 is fixed a high-pressure turbine rotor 20 having a number of blades formed on the outer periphery.
And the high-pressure turbine shroud 22. Outside the high-pressure turbine shroud 22, a scroll 24 connected to the catalytic combustor 12 via a transient duct 23 is provided, and a plurality of scrolls are provided between the inner periphery of the scroll 24 and the outer periphery of the high-pressure turbine rotor 20. Nozzle vanes 25 are provided. The scroll 24 is supported from the outer periphery by a plurality of support mechanisms 26, and the transient duct 23 is supported by other support mechanisms 27 and 28.

At the front end of the heat exchanger housing 2 connected to the rear part of the outer casing 1, a collector housing 29 is provided.
, And a low-pressure turbine shaft 30 is supported at the center thereof. A low-pressure turbine rotor 31 is fixed to the tip of the low-pressure turbine shaft 30, and a number of blades formed on the outer periphery of the low-pressure turbine rotor 31 fit into the inner surface of the low-pressure turbine shroud 32. The low pressure turbine shroud 32 and the high pressure turbine shroud 22 are connected by a low pressure turbine duct 34 having a variable stationary blade 33 at the rear end. The low pressure turbine shaft 30 is connected to the output shaft 35 via the speed reducer 14.

[0018] The upper half of the collector housing 29 arc-shaped opening 29 ₁ is formed, the heat exchanger after collection from the air passage 19 to the upper portion of the exhaust housing 3 1
3 is heated by passing through the upper half of the opening 29.
It is supplied to the inside of the inner casing 18 via ₁ .
On the other hand, the exhaust gas that has passed through the low pressure turbine shroud 32 is
Exhaust gas passage 29 ₂ for guiding in the lower half is formed.

A ring gear 36 is mounted on the outer periphery of the heat exchanger 13 over 360 °, and a plurality of guide rollers provided on the inner periphery of the heat exchanger housing 2 have a flat support surface formed at the front of the ring gear 36. It is rotatably supported by 37. A pinion 39 meshing with the ring gear 36 is fixed to a rotating shaft 38 that supports one guide roller 37, and the heat exchanger 13 is rotationally driven by rotating the rotating shaft 38 by a heat exchanger driving motor 40. You.

As shown in FIG. 3, the catalytic combustor 12 has a small-diameter portion 42 on the upstream side and a large-diameter portion 43 on the downstream side, and the end of the large-diameter portion 43 is connected to the transient duct 23. The outer periphery of the small diameter portion 42, a plurality of air inlet openings 42 ₁ for introducing hot air heated by passing through the heat exchanger 13 into the interior of the catalytic combustor 12 is formed. Small diameter section 42
Is provided with a preheater 45 connected to a power supply 44 to heat the intake air introduced into the catalytic combustor 12. The large-diameter portion 43 is provided with a catalyst carrier 46 and a fuel nozzle 47 as a fuel supply means for spraying fuel toward the catalyst carrier 46.

As shown in FIG. 4, the preheater 45 is formed in a honeycomb shape and has a function of rectifying the air passing therethrough.

As shown in FIG. 5, the catalyst supporting portion 46 is also formed in a honeycomb shape, and a catalyst 49 is supported on a surface in contact with the air-fuel mixture. Noble metal catalysts and non-noble metal catalysts can be used as the catalyst 49, and Pt, Pt-Ir, Pt-Pd, Pt-NiO, Pt
_{t-Co 2 O 2, Pt} -Pd-NiO, there is Pt-Ag, etc., and as the non-noble metal-based catalyst MnO _2, Co ₂ O
₂ , Co ₂ O ₄ , CuO and the like.

Next, the operation of the embodiment of the present invention having the above-described configuration will be described.

When the gas turbine engine G is in a normal operation state, the air flowing into the intake passage 6 through the air cleaner 4 and the silencer 5 is compressed to a high temperature and a high pressure by a compressor rotor 17 disposed inside the compressor casing 15. The air is sent rearward through a radial air passage 19 formed between the outer casing 1 and the inner casing 18. The intake air that has reached the inside of the exhaust housing 3 from the air passage 19 is gathered in the upper space of the exhaust housing 3, and then turns forward to turn the upper half of the core surface of the rotary heat exchanger 13. Pass later and later. Furthermore air that has been heated to a high temperature by passing through this way the heat exchanger 13, the inner casing 1 through an opening 29 ₁ formed in the upper portion of the collector housing 29
8 flows into the internal space.

The intake air supplied to the internal space of the inner casing 18 is introduced from the air introduction port 42 ₁ in the small-diameter portion 42 of the catalytic combustor 12, where the large diameter portion 43 to pass through the pre-heater 45 is not energized Inflow. Large diameter part 4
In 3, the mixture of the fuel supplied from the fuel nozzle 47 and the intake air flows into the catalyst carrier 46, where it contacts the catalyst 49 and burns. The combustion gas generated by the combustion of the air-fuel mixture flows into the scroll 24 from the transient duct 23, and is blown therefrom through the six nozzle vanes 25 to the high-pressure turbine rotor 20.

When the high-pressure turbine rotor 20 rotates in this way, the compressor rotor 17 provided on the high-pressure turbine shaft 16 rotates by its driving force. The combustion gas that has passed through the high-pressure turbine rotor 20 is blown to the low-pressure turbine rotor 31 via the low-pressure turbine duct 34 and the variable stationary blade 33, and drives the low-pressure turbine shaft 30 to rotate. Then, the rotation of the low-pressure turbine shaft 30 is reduced by the speed reducer 14 and taken out from the output shaft 35 to the outside. After the exhaust gas passing through the low-pressure turbine rotor 31 is collected by the exhaust gas passage 29 ₂ formed in the lower portion of the collector housing 29, it passes from the front lower half of the core surface of the rotary heat exchanger 13 back To heat the heat exchanger 13,
It is discharged to the exhaust duct 8. The heat exchanger 13 heated by the exhaust gas in this way is rotationally driven by the heat exchanger drive motor 40 via the pinion 39 and the ring gear 36, and the heated core surface sequentially faces the intake air passage. To heat the intake air.

When the gas turbine engine G is started, the temperature of the intake air supplied to the catalytic combustor 12 is lower than the catalyst activation temperature at which the catalyst 49 functions since the heat exchanger 13 is at a low temperature. . Therefore, at the time of starting, the power is supplied from the power supply 44 to the preheater 45 to heat the air passing therethrough to a catalyst activation temperature or higher, and to supply a mixture of fuel and the heated air to the catalyst carrier 46. Ignite. When the air-fuel mixture starts burning in this way, the heat of the exhaust gas heats the intake air via the heat exchanger 13, and the temperature of the intake air supplied to the catalytic combustor 12 eventually activates the catalyst. If the temperature rises above the temperature, the operation of the gas turbine engine G can be continued even when the power supply to the preheater 45 is stopped.

As described above, by spraying the fuel with the fuel nozzle 47 into the high-temperature air flow passing through the preheater 45, the evaporation of the fuel is promoted, and the combustion efficiency can be improved. Moreover, the preheater 45 having a honeycomb structure
The air having flow velocity uniformized by passing through the
6, stable combustion of the fuel can be achieved.

FIG. 6 shows a modification of the first embodiment. In this modification , a fuel nozzle 47 as a fuel supply means is disposed upstream of the preheater 45, and the fuel nozzle 47 is connected to the preheater 45. The fuel is sprayed toward. As a result, the fuel comes into contact with the surface of the pre-heater 45 having the honeycomb structure to promote the evaporation, and the flow velocity distribution of the air-fuel mixture generated by the rectifying action of the pre-heater 45 having the honeycomb structure is made uniform.
6, the air-fuel mixture can be stably burned.

FIG. 7 shows a second embodiment of the present invention.
The catalytic combustor 12 of the second embodiment includes the
A second catalyst carrier 50 is provided between the fuel tank 47 and the fuel nozzle 47. The catalyst supporting section 50 also has a catalyst 49 supported on the surface of the honeycomb structure.
It has a built-in catalyst heater (not shown) that generates heat when energized by the heater.

According to the second embodiment, when the air-fuel mixture heated by the pre-heater 45 flows into the upstream catalyst carrier 50, the catalyst carrier 50 Since the mixture is heated to the activation temperature or higher, the mixture can be sufficiently reacted with the catalyst 49 and burned. The air-fuel mixture that has passed through the catalyst carrier 50 in a partially unburned state is also mixed with the catalyst carrier 46 downstream thereof.
Can be completely burned. In addition, the fuel sprayed from the fuel nozzle 47 is promoted to evaporate by the surface of the catalyst carrier 50 heated by the catalyst heater, so that the combustion efficiency is improved.

Although the embodiment of the present invention has been described in detail, the present invention is not limited to the above-described embodiment, and various small design changes can be made.

For example, in the embodiment, the preheater 45 is energized when the gas turbine engine G is started. The preheater 45 may be energized during a low load operation in which the temperature does not easily rise.

[0034]

According to a first aspect of the above the present invention, in a gas turbine engine, is provided with the preheater of the electric upstream of the catalyst-carrying portion, the gas turbine ene
When starting the gas turbine, the temperature of the air-fuel mixture in contact with the catalyst is raised above the catalyst activation temperature to start the gas turbine engine.
Dynamic operation can be performed accurately . Moreover not only is possible to significantly reduce the generation amount of the NO _X which becomes a problem when using a conventional Puribana, also the deterioration of the catalyst which becomes a problem when preheating the catalyst using only conventional catalyst heater Can be avoided. Further, by supplying the fuel downstream of the preheater, the evaporation of the fuel is promoted by the high-temperature airflow passing through the preheater, and a uniform air-fuel mixture can be obtained to improve the combustion efficiency.

In addition, the conventional gas turbine engine
In operating conditions (ie, fully warmed up), the exhaust gas
Of the high pressure air from the compressor
Because it can be heated, it is
Contact with the catalyst even if the operation of the preheater is stopped
Mixture to be maintained above the catalyst activation temperature
Which contributes to the reduction of power consumption of the pre-heater
be able to. Further, the preheater is a gas turbine
It was sufficiently pressurized by the engine compressor and became hot
Comparison of calorific value because only high pressure air is heated further
It is possible to use a very small pre-heater,
In addition to contributing to power savings, the heater itself
Which contributes to cost savings (and thus to catalytic combustors) and miniaturization.
What you get.

According to a second feature of the present invention, by providing a catalyst heater in at least a part of the catalyst supporting portion, a synergy between heating of air or air-fuel mixture by the preheater and heating of the catalyst by the catalyst heater is provided. As a result, more stable starting performance can be obtained. In addition, since the load on the catalyst heater can be reduced by using the pre-heater together, there is no possibility that the catalyst is deteriorated.

According to the third feature of the present invention, the fuel is sprayed from the downstream of the pre-heater toward the catalyst heater, so that the fuel evaporation is promoted by utilizing the wall surface of the catalyst heater. The gasified mixture can be supplied to the catalyst.

According to a fourth aspect of the present invention, a gas turbine
In the low- pressure engine , an electric pre-heater was installed upstream of the catalyst carrier ,
At times, the temperature of the air-fuel mixture in contact with the catalyst is raised above the catalyst activation temperature to start the gas turbine engine.
I can definitely do it . Moreover not only is possible to significantly reduce the generation amount of the NO _X which becomes a problem when using a conventional Puribana, also the deterioration of the catalyst which becomes a problem when preheating the catalyst using only conventional catalyst heater Can be avoided. Further, the fuel is supplied to the upstream of the preheater, and the preheater is provided with a honeycomb structure to have a rectification function of the air-fuel mixture. Thus, stable combustion can be performed.

In addition, this fourth feature allows the gas
Normal (ie fully warmed) operation of the turbine engine
In the idle state, the heat of the exhaust gas is used to
Can sufficiently heat high-pressure air from
After the start of the engine is completed, the operation of the preheater is started.
Even when stopped, the air-fuel mixture in contact with the catalyst is kept at the catalyst activation temperature.
It is possible to maintain more than that
Power consumption can be reduced. Also the pre
The heater is sufficient for the gas turbine engine compressor
Just heat the high-pressure air that has been heated to a high temperature
Therefore, the use of a preheater with a relatively small heat value is
If it is possible and therefore can contribute to further power savings,
The cost of the heater itself (and therefore the catalytic combustor)
In savings and miniaturization it is capable of contributing.

According to a fifth aspect of the present invention, the fuel is sprayed from the upstream of the pre-heater toward the pre-heater, so that the evaporation of the fuel is promoted by utilizing the wall surface of the pre-heater, and the gasification is sufficiently performed. The resulting mixture can be supplied to the catalyst.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a gas turbine engine according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line 2-2 of FIG.

FIG. 3 is an enlarged sectional view of a main part of FIG. 2;

FIG. 4 is an enlarged sectional view taken along line 4-4 in FIG. 3;

FIG. 5 is an enlarged sectional view taken along line 5-5 of FIG. 3;

FIG. 6 is a diagram corresponding to the above item 3 according to a modification of the first embodiment.

FIG. 7 corresponds to FIG. 3 according to a second embodiment of the present invention.

[Description of Signs] G Gas Turbine Engine 9 Compressor 10 High Pressure Turbine 12 Catalytic Combustor 13 Heat Exchanger 45 Preheater 46 Catalyst Carrier 47 Fuel Nozzle 49 as Fuel Supply Means Catalyst 50 Catalyst Carrier

Continuation of the front page (56) References JP-A-2-242003 (JP, A) JP-A-2-238204 (JP, A) JP-A-1-139906 (JP, A) JP-A-62-185316 (JP) , U)

Claims (5)

(57) [Claims] 1. A compressor for compressing intake air.
(9) and the height for driving this compressor (9).
Pressure turbine (10), fuel and said compressor (9)
The mixture with the high-pressure air supplied from the catalyst to the catalyst (49).
Combustion gas for driving a high-pressure turbine
A high-pressure turbine
The heat of the exhaust gas discharged from the
From the impreza (9) to the catalytic combustor (12)
Fewer heat exchangers (13) for preheating high pressure air
The catalyst (49) is carried in the catalytic combustor (12).
A gas turbine is provided upstream of the catalyst carrying portions (46, 50)
An electric preheater (45) capable of heating the high-pressure air when the bin engine is started is provided.
And supplying the fuel to the downstream of the 5), Antofagasta
-Bin engine. 2. The gas turbine engine according to claim 1, wherein a catalyst heater is provided on at least a part of said catalyst support portion (46, 50) . 3. Spraying fuel from downstream of the pre-heater (45) toward the catalyst heater.
The gas turbine engine according to claim 2 . 4. A compressor for compressing intake air.
(9) and the height for driving this compressor (9).
Pressure turbine (10), fuel and said compressor (9)
The mixture with the high-pressure air supplied from the catalyst to the catalyst (49).
Combustion gas for driving a high-pressure turbine
A high-pressure turbine
The heat of the exhaust gas discharged from the
From the impreza (9) to the catalytic combustor (12)
Fewer heat exchangers (13) for preheating high pressure air
The catalyst (49) is carried in the catalytic combustor (12).
Catalyst supporting portion for lifting a fuel supply means for supplying fuel to the upstream (46, 50) (47), said catalyst carrier part (46,5
0) and downstream of the fuel supply means (47)
The fuel supply means when starting the gas turbine engine.
Of electrical capable of promoting the evaporation of the fuel supply from (47) preheater (45) is provided, characterized in that the preheater (45) gave the rectifying function of the mixture as a honeycomb structure, a gas turbine engine . 5. The gas turbine engine according to claim 4 , wherein said fuel supply means (47) sprays fuel from upstream of said preheater (45) toward said preheater.