JPH0343457B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a safety control device for a gas turbine power plant having a fluidized bed combustor and a compressor for combusting pulverized fuel, and particularly to a safety control device for a compressor in a gas turbine power plant. This invention relates to a safety control device for a gas turbine power generation plant.

Gas turbine power plants are disclosed in Siyab, et al., U.S. Pat.
May 21st, and V. Day Bias “60−Mw
Particulate adsorption in which compressed air from a gas turbine operated by a compressor adsorbs carbon dioxide and sulfur dioxide. It is equipped with a fluidized bed reactor or fluidized bed combustor that diffuses the agent. The gaseous products of the combustor are removed by a separator (gas cleaning device) that removes solids carried from the combustor.
The gas is then guided to the gas turbine, which acts as a generator for load operation.

In the operation of such gas turbine power plants, there is a problem in that when the gas turbine is stopped intentionally or accidentally, pressure surges and shocks occur due to load loss. Fluidized bed combustors and separators, or combustion product gas scrubbing devices, are compressed and supplied with extremely large volumes of gas, so that high-temperature gas fluids (e.g. 55,000 ft ³ between 371°C and about 1051°C) (volume) is not released quickly, and when the plant is shut down and the compressor output is reduced or dropped, a flow of gas fluid occurs from the fluidized bed combustor towards the compressor. This backflow of hot gas fluid creates back pressure at the discharge of the compressor, which back pressure is forced into the compressor and damages the compressor.
Additionally, the hot gases and finely divided solids such as unburned coal, dolumite, and ash in the conveyed gas stream can cause compressor damage to other components.

This invention was made in view of the above points,
An object of the present invention is to provide a safety control device for a gas turbine that prevents solid matter from flowing into a compressor and generation of surges when the heater load is lost in a gas turbine power generation plant having a fluidized bed combustor.

This means safety for gas turbine power plants that prevents the backflow of gas fluid from the fluidized bed combustor to the compressor and shuts down the plant with the fluidized bed combustor without generating surges and without damaging the compressor. The purpose is to provide a control device.

The safety control device of the present invention is installed in a gas turbine power plant having a fluidized bed combustor that burns pulverized fuel to produce high-pressure combustion gas. Compression means having an air inlet and an air outlet, the air outlet being connected to the fluidized bed combustor by a first conduit means, for suspending the pulverized fuel and inert material to promote combustion. Compressed air is sent to the fluidized bed combustor. The plant is also provided with an expander, such as a gas turbine, which is connected to the fluidized bed combustor by a second conduit means. The gas turbine is operated by combustion gas fed from a fluidized bed combustor.

The second conduit means is also provided with valve means for controlling the flow of combustion gases and for blocking the flow to the expander at predetermined operating positions.
The automatic control means, for example a check valve, is provided in the first conduit means to shut off gas flowing through the first conduit means from the fluidized bed combustor to the compression means. Venting means are provided for blowdown of the fluidized bed combustor with shutdown of the plant.

The first conduit means in the safety control device of this embodiment transports a portion of the compressed air from the fluidized bed combustor to the compressor means to diffuse the granular solid fuel and sulfur dioxide adsorbent to promote combustion of the granular solid fuel. a branch conduit for conveying a portion of the compressed air to the fluidized bed combustor in order to control the temperature within the fluidized bed combustor by heat exchange, and for facilitating the removal of solids entrained in the combustion gases. and a branch conduit for sending a portion of the compressed air to the separating means. and the automatic control means is two check valves, one of which is provided between the two branch conduits of the first conduit means;
Another check valve is provided between the remaining branch conduit and the air outlet of the compression means.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a safety control device for a gas turbine power plant according to the present invention will be described in detail below with reference to the accompanying drawings.

Reference number 10 is a gas turbine power plant having a safety control device according to an embodiment of the present invention. The power plant includes a fluidized bed combustor 12 having a reaction or combustion zone 18, two inlet high pressure sections 20, 22, and an outlet high pressure section 24. Three transverse partitions dividing the interior into four parts 1
4, 15, and 16. Fluidized bed combustor 12
is coupled via a conduit 26 to a fuel supply means 28 which supplies granular solid fuel to the combustion zone 18. The granular solid fuel used in this fluidized bed combustor 12 may be coal. Also,
The fluidized bed combustor 12 is connected to the supply means 3 via a conduit 32.
0, the supply means supplying a sulfur dioxide adsorbent, such as ground dolumite, to the combustion zone 18. The partition 14 is perforated or has a horn to allow the high pressure section 2 into the combustion zone 18.
Air is supplied from 0. To control the combustion temperature within the combustion zone 18 , a heat exchanger 34 is inserted into the combustion zone 18 to introduce air from the inlet high pressure section 22 and to discharge heat exchanged gas into the outlet high pressure section 24 . is combined with Combustion zone 18
The ash produced therein is removed from the combustion zone 18 via a discharge conduit 21, an ash cooler 23 and an ash hopper 25.

The compressed air is delivered to the compressor 3 via a main conduit 36 and a branch conduit 40 constituting the first conduit means.
8 into the inlet high pressure section 20. On the other hand, cold air from the compressor 38 is distributed and supplied to the inlet high pressure section 22 via the main conduit 36 and the branch conduit 41. The flow of compressed air through branch conduits 40 and 41 is regulated by valves 42, 44 within each pipe. valve 42,
44 regulates the distribution of the compressed air discharged from the compressor 38, approximately one-third of which is introduced into the high pressure section 20 to diffuse the granular solid fuel and promote combustion of the fuel; 2/3 is distributed to high pressure section 22 and flows to heat exchanger 34 to cool combustion zone 18.

One end of bypass conduit 46 connects to main conduit 36 from which compressed air is introduced and passes through auxiliary combustor 48 . Fuel, such as gas or oil, is selectively injected into the auxiliary combustor 48 to provide hot gas to the high pressure section 20 via conduit 40 when it is necessary to heat the compressed air at start-up. A valve 50 is provided to the bypass conduit 46 and controls the flow of compressed air to the auxiliary combustor 48 .

Starter combustor 52 receives compressed air from main conduit 36 via conduit 54 to produce combustion gases. A valve 55 is provided within conduit 54 to control flow therethrough. The combustion gases are conveyed from the starter combustor 52 to the turbine via conduit 58 and a clean combustion gas conduit 60.
This clean combustion gas conduit 60 is equipped with a valve 61. The gas turbine 56 is the compressor 3
Combined to drive 8.

A cleaning system is provided within the plant, which cleans the combustion gases discharged from the fluidized bed combustor 12 via outlet conduit 76 to conduits 70, 7.
2, 74 to continuously supply the separators 62, 64, 66, 68 connected in series. Separator 62 is connected to fluidized bed combustor 12 via conduit 71 and the unburnt particulate solid fuel, carried along with the combustion gases and separated in separator 62, is returned to combustion zone 18.
Clean combustion gases are discharged from separator 68 via outlet conduit 78 and flow into clean combustion gas conduit 60 and conveyed to gas turbine 56 .
The outlet conduit 78 connects to vent means comprising a conduit 80 having a valve 82, which vent means is connected to a conduit 85 for controlling the fluid flow discharged by the water washer 84. The separator 68 is
Since air is required, it is connected to the fluidized bed combustor 12 by a conduit 88. The conduit 88 is connected at one end to the outlet high pressure section 24 of the fluidized bed combustor 12 and at the other end to the separator 68. Some of the compressed air passes through the separator 6 through a bypass conduit 90 that is coupled to the main conduit 36 and the conduit 88.
8 directly. A valve 92 is inserted into conduit 90 to control the flow rate therethrough. Compressed air is allowed to flow through separator 68 and into clean combustion gas conduit 60 via bypass conduit 94 with valve 96 .

Gas turbine 56 is connected for exhaust gas discharge to free turbine 100 by conduits 102 and 103. Isolation valve 104 is inserted into conduit 103 and controls the flow of exhaust gas from gas turbine 56 into free turbine 100 . A valve-controlled bypass conduit 106 is also provided to pass exhaust gas from the gas turbine 56 to the exhaust conduit 108 of the free turbine 100. Conduit 110 is configured to introduce exhaust gas from exhaust conduit 108 of free turbine 100 or from exhaust conduit 102 of gas turbine 56 to a waste heat boiler (not shown). Valve 1
12 is provided in a conduit 110 which introduces exhaust gas from the gas turbine 56 into a bypass leading to a free turbine 100 and is connected to a waste heat boiler. The free turbine 100 is an alternator 1
14.

The safety control device of this embodiment has a bypass conduit 116 that communicates at one end with the main conduit 36 and at the other end communicates with the atmosphere via a muffler (not shown). The bypass conduit 116 is equipped with an anti-surge valve 11 that opens to release compressed air to the atmosphere in the event of a sudden load loss due to an emergency shutdown of the plant.
8 is provided. Automatic control means are provided to shut off gas flowing in main conduit 36 from fluidized bed combustor 12 to compressor 38. The automatic control means comprises a check valve 120 in the main conduit 36 downstream of its junction with the bypass conduit 116. The automatic control means also includes a second check valve 122 provided in the main conduit 36 between the connection of the branch conduit 40 and the connection of the branch conduit 41. This check valve 122
conduits 37, 36, 54, 58, and 60 if the series of valves 42, 50, and 55 remain open during a sudden load loss or plant shutdown.
A series of valves 42 and 5 block gas flow from fluidized bed combustor 12 to turbine 56 through a series of valves 42 and 5.
0, 92, 96, and 61 remain open, blocking the flow of gas from the fluidized bed combustor 12 to the turbine 56 through conduits 37, 36, 90, 94, and 60. Shutdown of plant 10 and separator 6
In order to effect the cleaning means comprising 4, 66 and 68 and the blowdown or pressure reduction of the fluidized bed combustor 12, valves 82 and 86 are opened and valve 61 is closed. The fluidized bed combustor and cleaning means are thereby ventilated via conduits 80 and 85. The vented gas is washed in a water scrubber 84 before being released into the atmosphere to avoid contamination.

A fluidized bed that ventilates the compressor during load losses and allows blowdown of the fluidized bed combustor without causing surges or damaging the compressor by particulate solids entering through the exhaust port. A safety control device for a gas turbine with a combustor is provided.

The present invention is not limited to the above embodiment, but
Various modifications can be made without departing from the spirit of the invention.

[Brief explanation of drawings]

The accompanying drawing is a block diagram of a safety control system for a gas turbine power plant according to the present invention. DESCRIPTION OF SYMBOLS 12...Fluidized bed combustor, 28...Crushed fuel supply means, 34...Heat exchanger, 36...Main conduit, 38...
Compressor, 40, 41, 90... Branch conduit, 56
...Gas turbine, 62,64,66,68...Separator, 84...Water cleaning device, 100...Free turbine, 120,122...Check valve.

Claims (1)

[Claims] 1. A fluidized bed combustor that generates combustion gas by burning pulverized fuel supplied from a fuel supply means, a compression means having an air inlet and an air outlet, and a fluidized bed combustor that diffuses the pulverized fuel. first conduit means communicating an air outlet of said compression means with said fluidized bed combustor to promote combustion; expander means; a second conduit means for guiding the combustion gas to the expander means, the safety control device for a gas turbine power plant being provided in the second conduit means upstream of the expander means; valve means for stopping the flow of said combustion gas supplied to said expander means upon shutdown; and an automatic valve provided in said first conduit means for stopping the flow of gas fluid from said fluidized bed combustor towards said compression means. A safety control device for a gas turbine power plant, comprising a control means. 2. The gas turbine power generation system according to claim 1, wherein the expander means includes a gas turbine that operates the air compression means, and a free turbine that operates the load by introducing exhaust gas from the gas turbine. Plant safety control equipment. 3. A safety control system for a gas turbine power plant according to claim 1, wherein said automatic control means comprises at least one check valve. 4. The first conduit means comprises a valve-controlled bypass conduit communicating between the outlet of the air compression means and the automatic control to allow compressed air to bypass the fluidized bed combustor. A safety control device for a gas turbine power generation plant according to item 2. 5. The fluidized bed combustor comprises a heat exchanger for controlling temperature, the second conduit means has separation means for removing solid particles carried with the combustion gas from the combustion gas, and the first conduit means , comprising a first branch conduit for introducing compressed air into the heat exchanger and a second branch conduit for introducing compressed air into the separating means, the automatic control means being provided in the first conduit means. two check valves, the first check valve being provided downstream of the connection between the first and second branch conduits and the first conduit means, and the second check valve being provided downstream of the connection between the first and second branch conduits and the first conduit means 2. The safety control device for a gas turbine power plant according to claim 1, wherein the safety control device is provided upstream from a connecting portion between the first and second branch conduits and the first conduit means.