KR820001568B1 - Gas turbine plant - Google Patents

Abstract

A gas turbine(15) drives a compressor(10) & a generator(22). The air from the compressor is taken to a sperical press. vessel(2) which contains an annular combustion chamber(4) with a fluidized bed(3). The hot combustion gases are taken to the turbine. Because of the sizes involved for an installation of 100 MW. or more the combustion chamber is remote from the turbine with a long pipe connection between them. The gas pipe(17) from the combustion chamber is supported concentrically within an outer pipe(18). The air from the compressor flows through the annular space(21) between the inner & outer pipes and reduces the heat losses from the hot gas.

Description

Gas turbine plant

1 is a schematic of a gas turbine plant.

2 is a partial cross-sectional view of the connecting piping between the turbine and the combustion chamber of the plant.

3 is a radial cross-sectional view of the tube seen from line A-A in FIG. 2;

4 is a radial cross-sectional view of a conduit according to another embodiment.

5 is an enlarged cross-sectional view of the conduit inner tube viewed from the line B-B in FIG.

6 is a longitudinal cross-sectional view of the inner tube of the second portion C.

FIG. 7 is a cross-sectional view of the conduit seen from line D-D of FIG.

8 is a cross-sectional view of the flexible connection pipe part E of FIG.

The present invention relates to a 100 MW or higher high power gas turbine plant comprising a combustion chamber separate from the turbine for heating the propulsion gas of the turbine.

This heating is performed by combustion of fuel by compressed combustion air supplied from a compressor in the plant. The invention is particularly suitable for gas turbine plants operated by coal combusted in a fluidized bed.

In a plant of this kind, the fluidized bed and the flue gas sweeper must be contained in a pressure container of the appropriate size, which container is suitably arranged outdoors or in an isolated building. The gas conduits are therefore relatively long.

It is an object of the present invention to provide a plant with less heat loss during transfer of hot propulsion gas from a combustion chamber to a turbine.

A second object of the present invention is to heat the conduit conveying the combustion gas from the combustion chamber to the compressed air so that the strength of the conduit is not reduced by heating, while at the same time returning the lost heat together with the compressed air to the combustion chamber. To be useful.

A third object is to reduce the stress in the hot gas conduit by balancing the excess pressure inside and outside.

A fourth object of the present invention is to reduce the motion between the hot gas conduit and the carrier due to thermal expansion.

According to the present invention, there is a conduit between the combustion chamber and the turbine, the conduit comprising an inner tube and an annular gap that maintains an annular spacing for transporting hot propulsion gas from the combustion chamber to the turbine, the outer annular gap of which is the annular spacing. Conveys compressed air from the compressor in the plant to the combustion chamber.

Inside the inner tube is a casing tube of heat-resistant material consisting of several parts, an annular gap is formed between the inner tube and the casing, the gap may be a layer of insulating material inserted. The parts of the casing tube are suitably joined to the inner tube of the conduit at at least three circumferences.

Casing tube components are to be installed axially movable relative to adjacent casing tube components. This method allows the casing tube to elastically deform radially between fixed points upon temperature change.

The coaxial tube is axially fixed to the combustion chamber as appropriate.

The thermal movement between the fixed point of the gas turbine and the fixed point of the combustion chamber is absorbed by the expansion device connected to the turbine. The conduit may be installed horizontally with the bend, inclined between the combustion chamber and the bend, and may be vertical between the bend and the gas turbine connection.

Strain absorbing coupling devices that allow horizontal displacement of the bends relative to the gas turbine are usually applied to the vertical part of the conduit between the turbine and the bend.

The coupling device is a metal bellows or sleeve joint, and the sleeve on the tubular part receives the end in the adjacent tube part. The sleeve and / or tube end can be annularly deformable and can be made to have a spherical union surface. The sealing ring between the pipe parts may be a piston ring seal. Hereinafter, with reference to the accompanying drawings will be described in detail.

In the drawing, the combustion chamber 1 consists of a spherical container 2, in which an annular distribution layer 3 is embedded in a closed annular container 4, and the spherical container 2 and the annular container 4 It is supported by the stand 5.

The annular container 4 is provided with the bottom part 6 containing pores, and the annular air chamber 7. The air chamber 7 is provided with valves 8 for regulating the combustion air supplied from the space 9 of the spherical container 2, the space 9 being compressed air from the compressor 10 of the gas turbine plant. To house.

The container 4 is equipped with the cooling pipe 11 for fluidized bed 3 cooling below. The cooling tube may form part of a steam generator for a steam turbine plant operating in parallel with a gas turbine plant.

There is a series of connected dust separators 13 and 14 between the container 4 of the flow type 3 and the annular collecting tube 12.

The gas turbine 15 and the compressor 10 driven by the gas turbine 15 are connected to the combustion chamber 1 via a conduit 16 consisting of two coaxial tubes 17 and 18. The pipe 17 is connected to the gas collection pipe 12, and transfers the hot gas from the combustion chamber 1 to the gas turbine 15, the flow of hot gas is like the arrow (19). The tube 18 is connected to the container 2 and the compressor 10 and transfers compressed air from the compressor 10 to the space 9 between the wall of the container 2 and the device embedded therein.

Compressed air flows in the annular air 20 as shown by arrow 21.

The turbine 15 also drives the generator 22. The exhaust gas from the turbine 15 is transferred to the heat exchanger 23 so that the residual heat of the gas is utilized and can be used for preheating the feed water.

As mentioned above, the spherical container 2 is under pressure.

In this type of gas turbine plant, the internal excess pressure will be between 15 and 20 bar and the turbine propulsion gas will be between 800 and 900 ° C.

Through the present invention, the pressure of both air in the annular space 20 corresponds mainly to the pressure of the hot gas in the tube 17, which means that the tube 17 carrying the hot gas is only subjected to a slight stress. At the same time, the compressed air in the gap 20 cools the tube 17 so that the tube can be kept sufficiently cold with respect to strength.

When the inner tube 17 is cooled, compressed air, that is, combustion air, is preheated.

The heat lost from the hot gas is returned to the combustion chamber and used together with the compressed air. The temperature of the gas leaving the fluidized bed is adjusted so that the required temperature is obtained at the inlet of the turbine 15.

It is possible to maintain the temperature of the tube 17 at about 200 ° C. The tube 17 is made of strength that can easily withstand outward excess pressure due to pressure drop in the conduit 17 and in the fluidized bed 3.

Temperature control is achieved in whole or in part by cooling the walls of the annular container 4 with the cooling conduits 11, in which water or steam flows. Temperature control is also achieved by adjusting excess air during combustion in the fluidized bed 3.

The residual heat of the propellant gas is treated in a heat exchanger after the turbine and used, for example, for preheating the feedwater of a steam plant operating in parallel with the gas turbine.

The inner tube 17 of the conduit 16, as shown in FIGS. 2, 3 and 4, is centered in the tube 18 by multiple tubes 25 or multiple types of fixtures arranged parallel to the observation. do.

The outer tube 18 is supported by a plurality of struts 16.

In the inner tube 17, a plurality of relatively short casing tubes 27 are embedded and fixed to the inner tube 17 by the fixing elements 28 at three places. This is shown in FIG. 5 and FIG.

The ends of the casing tube 27 are formed to be able to move in the axial direction with each other when the length is changed by the temperature change.

The three attachments make the casing pipe 27 deformable in the radial direction as shown in FIG.

The shape of the tube under low temperature and high temperature conditions is shown by (27a) and (27b), respectively. There may be a support 30 between the fixed elements 28.

There is a layer of insulating material 31 in the space between the tube 17 and the casing tube 27, and the tube 18 is covered with the insulating layer 32.

The tube 17 and the tube 18 are fixed to the combustion chamber 11 in the axial direction.

The curved tube 33 is connected to the turbine housing 34 by a coupling 35 to allow horizontal displacement when the horizontal portion of the conduit 16 changes its length in response to temperature changes.

A bellows 38 is inserted between the flange 36 on the outer tube 39 of the curved tube 33 and the flange 37 on the turbine housing.

The flanges are joined by a number of bolts that are forced through the air pressure in the conduit 16. Some bolts include spacers to maintain the distance between the flange 36 and the flange 37.

There is a coupling 43 between the curved tube 42 of the inner tube 17 and the vertical portion 17a of the inner tube 17, allowing any annular deformation.

The coupling 43 has a spherical surface respectively in the sleeve 44, the lower end of the curved pipe 42, and the pipe part 17 in the tube 17a and the turbine housing 34, respectively, and the spherical surface 45 is a sleeve. It is injected into 44. The sealing piston ring 47 is mounted in the groove 46.

Claims (1)

A combustion chamber having an inlet and an outlet, a gas turbine having an inlet arranged at a distance from the combustion chamber, a compressor having an outlet for supplying compressed air to the combustion chamber, an internal heat insulating material, the inlet of the turbine and the combustion chamber An inner conduit disposed between the outlets, a casing tube disposed therein at a distance from the inner conduit to form an annular gap between the inner conduit, and an inlet of the combustion chamber for transporting air through a defined gap between the outer conduit And an outer conduit disposed coaxially around the inner conduit between the outlet of the compressor and the gas turbine plant.

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