JP2000282809A - Coal gasification combined cycle power plant - Google Patents

Abstract

(57) Abstract: Coal supplied from a desulfurization / dust removal device to a gas turbine combustor of a gas turbine plant when cleaning a dust removal filter incorporated in a desulfurization / dust removal device of a coal gasification plant. Provided is a coal gasification combined cycle power plant that prevents a decrease in calorific value of gasified gas fuel. A coal gasification combined cycle power plant according to the present invention is provided with a coal gasification gas fuel control system (39) in a gas turbine plant (18) and desulfurization of the coal gasification plant (17) by the coal gasification gas fuel control system (39).・
The coal gasification gas fuel supplied from the dust removal device 27 to the gas turbine combustor 29 of the gas turbine plant 18 is controlled.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coal gasification combined cycle power plant in which a gas turbine plant, a waste heat recovery boiler, and a steam turbine plant are combined with a coal gasification plant.

[0002]

2. Description of the Related Art In recent thermal power plants, it is desired to further reduce the amount of fossil fuel used and to further improve the thermal efficiency of the plant.

[0003] Fossil fuels used in thermal power plants are CO ₂ and SOx, despite the fact that coal has abundant reserves compared to oil and natural gas, is cheap and can be supplied stably for a long time. The use of relatively clean fuels, such as oil and natural gas, is dominant even when expensive, due to the large amount of environmental pollutants emitted.

However, since the oil crisis in the 1970s, the danger of excessive dependence on oil as an energy source has been pointed out, and the number of years that oil and natural gas can be adopted has been around 50 years (according to the Energy Statistics of the ), It is becoming increasingly difficult to provide long-term stable prices and supplies of clean fuel. For this reason, the reuse of coal having a reserve of more than 300 years in thermal power plants is being reviewed.

[0005] Recently, a coal gasification combined cycle power plant using a coal gasification gas fuel in which coal is gasified to reduce the generation of CO ₂ , SOx and NOx as environmental pollutants has been realized. Fig. 5
There are the following.

A coal gasification combined cycle power plant (hereinafter referred to as IGCC) is a coal gasification plant 1
The gas turbine plant 2, the exhaust heat recovery boiler 3, and the steam turbine plant 4 are combined.

[0007] The coal gasification plant 1 includes a coal supply unit 5,
An oxygen production apparatus 6 and a coal gasifier 7 are provided.
Pulverized coal and oxygen gas from the oxygen production apparatus 6 are supplied to a coal gasifier 7, where a portion of the pulverized coal is burned, and the remaining temperature is maintained at 1400 ° C to 1800 ° C, which is higher than the melting point of coal ash. Are reacted based on the following equation to purify flammable coal gas containing carbon monoxide (CO) as a main component.

[0008]

## EQU1 ## CO ₂ + C = 2CO

The oxygen producing apparatus 6 includes an oxygen producing air compressor 9 driven by a motor 8, and compresses the air taken in by the oxygen producing air compressor 9 to a high pressure. O ₂ is separated into nitrogen gas N _2, and the separated oxygen gas O ₂ is supplied to a coal gasifier 7 to purify the combustible coal gas by so-called oxygen blowing. N ₂ is supplied to the gas turbine plant 2.

Further, the coal gasification plant 1 includes a cooler 1
0 and a desulfurization / dust removal device 11, and the above-mentioned coal gasifier 7
Combustible coal gas refined in
After the cooling, the desulfurization / dust removal device 11 removes impurities such as sulfur and dust, and supplies the gas turbine plant 2 as a clean coal gasification gas fuel.
The cooler 10 obtains cooling water from the steam turbine plant 4, cools the combustible coal gas, and then recovers the combustible coal gas again in the steam turbine plant 4 for effective utilization of heat.

On the other hand, the gas turbine plant 2
Compressor 12, gas turbine combustor 13, gas turbine 1
4. Equipped with a generator 15, the air sucked by the air compressor 12
Gas is compressed to high pressure, and the high pressure air is converted to coal gas.
Clean coal from desulfurization and dust removal equipment 11 of plant 1
Nitrogen gas N from gasification gas fuel and oxygen production device 6
₂Together with the gas turbine combustor 13, where the stone
Nitrogen gas N₂NOx
Generates low-concentration combustion gas, which is
The expansion work is performed in the bin 14, and the rotating torque generated at that time
The generator 15 is driven by the heat and the combustion gas after the expansion work is
The exhaust gas (exhaust heat) is supplied to the exhaust heat recovery boiler 3.

The exhaust heat recovery boiler 3 houses a heat exchanger 16 such as a superheater, an evaporator, and a economizer, uses the exhaust gas supplied from the gas turbine 14 of the gas turbine plant 2 as a heat source, and uses the exhaust gas as a heat source. The condensed water / supply water supplied from is exchanged in the heat exchanger 16 to generate steam, and the steam is supplied to the steam turbine plant 4.

The steam turbine plant 4 includes a steam turbine 17, a generator 18, a condenser 19, and a feedwater pump 20. The steam from the exhaust heat recovery boiler 3 and the steam from the cooler 10 in the coal gasification plant 1 described above. Into turbine driven steam, and the turbine driven steam is
7, the expansion work is performed, and the generator 18 is driven by the rotational torque generated at that time, and the turbine driving steam (turbine exhaust) having completed the expansion work is condensed in the condenser 19 and condensed.・ Water supply, and return and supply water
A part is supplied to the cooler 10 via the refrigeration system, and the rest is returned to the exhaust heat recovery boiler 3.

As described above, in the IGCC in which the gas turbine plant 2, the exhaust heat recovery boiler 3, and the steam turbine plant 4 are combined with the coal gasification plant 1, the clean coal gasification gas purified from the coal gasification plant 1 is used. While the fuel is used for the gas turbine driving gas, the Brayton cycle of the gas turbine plant 2 and the Rankine cycle of the steam turbine plant 4 are skillfully combined,
They were working to reduce NOx and improve plant thermal efficiency, and to deal with the reuse of coal.

[0015]

The conventional I shown in FIG.
The GCC uses coal gasification gas fuel as a clean fuel and can keep the NOx concentration within the legally regulated value, but it still has some problems, one of which is the desulfurization / dust removal device 11. There is a problem of clogging of the dust filter incorporated in the apparatus.

The IGCC monitors clogging of a dust filter incorporated in the desulfurization / dust removal device 11 in order to maintain a constant normal operation of the desulfurization / dust removal device 11. Accordingly, during the operation of the coal gasification plant 1, so-called back washing, in which an inert gas, for example, high-pressure nitrogen gas is blown from the downstream side to the upstream side of the dust filter, has been routinely performed. At this time, the coal gasification plant 1
Since the inert gas is injected into the coal gasification gas fuel having a high calorific value, the calorific value of the fuel is significantly reduced, and accordingly, the output of the gas turbine plant 2 cannot be maintained as designed, and the fuel gas becomes unstable. There were often problems and inconveniences that caused troublesome operation.

The present invention has been made in view of such circumstances, and even when removing impurities from a dust filter installed in a desulfurization / dust removing device, a coal gas generated from a coal gasification plant is used. It is an object of the present invention to provide a coal gasification combined cycle power generation plant that maintains a high calorific value of a gasification gas fuel and performs a stable operation of a gas turbine plant.

[0018]

In order to achieve the above object, a combined gasification combined cycle power plant according to the present invention is provided with a gas turbine plant, a waste gas turbine, and an exhaust gas. In a coal gasification combined cycle power plant that combines a heat recovery boiler and a steam turbine plant, when cleaning the dedusting filter incorporated in the desulfurization and dedusting device of the coal gasification plant, the desulfurization and dedusting device A coal gasification gas fuel control system for compensating for the decrease in the calorific value of the coal gasification gas fuel supplied to the gas turbine combustor of the gas turbine plant and controlling the flow rate of the coal gasification gas fuel is provided in the gas turbine plant. It is provided.

In order to achieve the above object, a coal gasification combined cycle power plant according to the present invention includes a coal gasification gas fuel control system,
A state quantity detector that detects the state quantity of the desulfurization and dust removal equipment of the coal gasification plant, and calculates based on the detection signal from the state quantity detector, and compares the calculated signal with a predetermined setting signal. And a calculation controller for operating a fuel control unit provided on the inlet side of the gas turbine combustor of the gas turbine plant based on the deviation when the deviation occurs.

[0020] In order to achieve the above object, a coal gasification combined cycle power plant according to the present invention comprises a coal gasification gas fuel control system comprising:
A state quantity detector that detects a state quantity of a desulfurization / dust removal device of a coal gasification plant, and a state gas detector that is provided at an outlet side of a gas turbine combustor of a gas turbine plant and detects a combustion gas temperature generated by the gas turbine combustor. A temperature sensor to be detected, a calculation is performed based on a detection signal from the state quantity detector and a detection signal from the temperature sensor, and a predetermined setting signal is compared with the calculation signal. And a calculation controller for operating a fuel control unit provided on the inlet side of the gas turbine combustor based on the deviation.

According to a fourth aspect of the present invention, there is provided a coal gasification combined cycle power plant comprising a gas turbine plant, a waste heat recovery boiler, and a steam turbine. In a coal gasification combined cycle power plant that combines plants, the desulfurization and
When cleaning the dust filter installed in the dust removal device,
The reduction in the calorific value of the coal gasified gas fuel supplied from the desulfurization / dust removal device to the gas turbine combustor of the gas turbine plant is supplied to the gas turbine combustor from the air compressor of the gas turbine plant. An air compressor flow control system for controlling the flow rate of high-pressure air is provided in the gas turbine plant.

In order to achieve the above object, a combined gasification combined cycle power plant according to the present invention comprises an air compressor flow control system, a desulfurization and dust removal of a coal gasification plant. A state quantity detector for detecting the state quantity of the device, and a calculation is performed based on a detection signal from the state quantity detector, and a predetermined setting signal is compared with the calculation signal. And an arithmetic controller for operating an air flow control unit provided on the outlet side of the air compressor of the gas turbine plant based on the above.

According to a sixth aspect of the present invention, there is provided a coal gasification combined cycle power plant comprising a gas turbine plant, a waste heat recovery boiler, and a steam turbine. In a coal gasification combined cycle power plant that combines plants, the desulfurization and
When cleaning the dust filter installed in the dust removal device,
The flow rate of the auxiliary fuel supplied to the gas turbine combustor and the flow rate of the auxiliary gas supplied to the gas turbine combustor to compensate for the decrease in the calorific value of the coal gasified gas fuel supplied from the desulfurization / dust removal device to the gas turbine combustor of the gas turbine plant An air / auxiliary fuel combined control system for controlling at least one of the flow rates of high-pressure air supplied from the air compressor of the plant to the gas turbine combustor is provided in the gas turbine plant.

In order to achieve the above object, a combined gasification combined cycle power plant according to the present invention is provided with a combined air / auxiliary fuel control system as described in claim 7.
A state quantity detector for detecting a state quantity of a desulfurization / dust removal device of a coal gasification plant, and a state gas detector which is provided at an outlet side of a gas turbine combustor of a gas turbine plant and detects a combustion gas temperature generated by the gas turbine combustor. A temperature sensor to be detected, a calculation is performed based on a detection signal from the state quantity detector and a detection signal from the temperature sensor, and a predetermined setting signal is compared with the calculation signal. Calculation control for operating at least one of an auxiliary fuel control unit provided on the inlet side of the gas turbine combustor and an air flow control unit provided on the outlet side of the air compressor of the gas turbine plant based on the deviation It is composed of a container.

In order to achieve the above object, the coal gasification combined cycle power plant according to the present invention is characterized in that the state quantity of the desulfurization and dedusting device of the coal gasification plant is that of dust removal. The pressure difference is one of a pressure difference between the inside and outside of the filter and a flow rate of the inert gas to be supplied to the dust removal filter.

In order to achieve the above object, in the coal gasification combined cycle power plant according to the present invention, the auxiliary fuel may be any one of kerosene, light oil, residual oil, methanol and hydrogen gas. Is what you choose.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a coal gasification combined cycle power plant according to the present invention will be described below with reference to the drawings and the reference numerals in the drawings.

FIG. 1 is a schematic system diagram showing a first embodiment of a coal gasification combined cycle power plant according to the present invention.

The coal gasification combined cycle power plant according to the present embodiment includes a coal gasification plant 17
The gas turbine plant 18, the exhaust heat recovery boiler 19, and the steam turbine plant 20 are combined.

The coal gasification plant 17 includes the coal supply unit 2
1. An oxygen production apparatus 22 and a coal gasification furnace 23 are provided, and pulverized coal from the coal supply unit 21 and oxygen gas O ₂ from the oxygen production apparatus 22 are supplied to the coal gasification furnace 23. The temperature of the coal ash melting point and above 1500 ゜ ~ 1
The remaining pulverized coal is reacted based on the following equation while maintaining the temperature at 800 ° C. to purify flammable coal gas containing carbon monoxide (CO) as a main component.

[0031]

## EQU2 ## CO ₂ + C = 2CO

The oxygen producing apparatus 22 is provided with an oxygen producing air compressor 25 driven by a motor 24. The oxygen sucked by the oxygen producing air compressor 25 is compressed to a high pressure. ₂ and nitrogen gas N _2, and the separated oxygen gas O ₂ is supplied to the coal gasifier 23 to purify the combustible coal gas by so-called oxygen blowing, while the separated nitrogen gas N ₂ Is supplied to the gas turbine plant 18.

Further, the coal gasification plant 17 is provided with a cooler 26 and a desulfurization / dust removing device 27, and the combustible coal gas refined in the coal gasification furnace 23 described above is cooled by the cooler 26 to about 40%.
After being cooled to 0 ° C., impurities such as sulfur and dust are removed by a desulfurization / dust removal device 27 and supplied to the gas turbine plant 18 as clean coal gasified gas fuel.

The gas turbine plant 18 includes an air compressor 28, a gas turbine combustor 29, a gas turbine 30, and a generator 31, and compresses the air sucked by the air compressor 28 to a high pressure. together with the nitrogen gas N ₂ from clean coal gasification gas fuel and air separation unit 22 from the desulfurization and dedusting apparatus 27 of the coal gasification plant 17 is supplied to the gas turbine combustor 29, here the coal gasification gas fuel The combustion gas is diluted with nitrogen gas N ₂ to generate a combustion gas having a low NOx concentration, and the combustion gas is subjected to expansion work by the gas turbine 30, and the generator 31 is driven by the rotating torque generated at that time, thereby reducing the expansion work. The completed combustion gas is supplied to the exhaust heat recovery boiler 19 as exhaust gas (exhaust heat).

The exhaust heat recovery boiler 19 includes a superheater, an evaporator,
A heat exchanger 31 such as a economizer is accommodated, and the exhaust gas supplied from the gas turbine 30 of the gas turbine plant 18 is used as a heat source.
The feed water is heat-exchanged by the heat exchanger 31 to generate steam, and the steam is supplied to the steam turbine plant 20.

The steam turbine plant 20 includes a steam turbine 32, a generator 33, a condenser 34, and a water supply pump 35, and supplies steam from the exhaust heat recovery boiler 19 to the steam turbine 32 as turbine driving steam. The expansion work is performed, the generator 33 is driven by the rotational torque generated at that time, and the turbine driving steam (turbine exhaust) having completed the expansion work is condensed by the condenser 34 to be condensed and supplied, and the condensate is condensed. A part of the feedwater is supplied to the cooler 26 of the coal gasification plant 17 via the feedwater pump 35, and the rest is returned to the exhaust heat recovery boiler 19.

In the coal gasification combined cycle power plant, the outlet side of the cooler 26 of the coal gasification plant 17 is connected to the gas turbine high temperature section 36 of the gas turbine 30,
For example, a cooling steam supply system 37 connected to a gas turbine vane, a gas turbine blade, a gas turbine rotor, and the like, and an outlet side of the gas turbine high temperature section 36 are connected to the steam turbine plant 20.
A cooling steam recovery system 38 connected to the inlet side of the steam turbine 32 is provided, and the high temperature coal gasification gas fuel from the coal gasification furnace 23 and the condensate / water supply from the steam turbine plant 20 are cooled by the cooler 26. Heat exchange is performed, and steam generated at that time is supplied as cooling steam to the gas turbine high temperature section 36 of the gas turbine 18 to cool the gas turbine high temperature section 36 and to cool the gas turbine high temperature section after cooling. The steam is recovered by the steam turbine 32.

On the other hand, the gas turbine plant 18 is provided with a coal gas fuel control system 39.

During the operation, the coal gasification gas fuel control system 39 controls the inert gas, the inert gas, For example, in consideration of the fact that the calorific value of the coal gasified gas fuel is reduced due to the introduction of nitrogen gas, a state quantity detector 40, a calculation controller 41, and a fuel control unit 42 are provided. One of the pressure difference and the flow rate of the inert gas supplied to the dust filter is detected by the state quantity detector 40, and the detection signal is obtained by the operation controller 4.
1 and calculates the signal. The calculated signal is compared with a predetermined setting signal. When a deviation is found, the operation of the fuel control unit 42 is adjusted based on the deviation, and the desulfurization / dust removal device 27 is controlled. From the gas turbine combustor 29 of the gas turbine plant 18
To control the amount of clean coal gasification gas fuel supplied to the plant.

As described above, in this embodiment, the coal gasification gas fuel control system 39 is provided in the gas turbine plant 18, and the dust filter incorporated in the desulfurization / dust removal device 27 is backwashed with the inert gas. At this time, the fuel control unit 4 is controlled according to the pressure difference between the inside and outside of the dust filter or the flow rate of the inert gas.
2 was adjusted and the flow rate of the coal gasified gas fuel was increased by an amount corresponding to the decrease in the calorific value of the coal gasified gas fuel, so that the gas turbine combustor 29 provided a stable calorific value of the coal gasified gas fuel. Gas turbine 3
The output from 0 can be kept high.

FIG. 2 is a schematic system diagram showing a second embodiment of the coal gasification combined cycle power plant according to the present invention. Note that the same reference numerals are given to the same or corresponding portions as the components of the first embodiment.

In the coal gasification combined cycle power plant according to the present embodiment, an air compressor flow control system 43 is provided in the gas turbine plant 18 and is incorporated in the desulfurization / dust removal device 27 of the coal gasification plant 17 during operation. When the dust filter is back-cleaned, the gas is supplied from the air compressor 28 of the gas turbine plant 18 to the gas turbine combustor 29 corresponding to one of the pressure difference between the inside and outside of the dust filter and the flow rate of the inert gas to be supplied. The flow rate of the high-pressure air is controlled by the air compressor flow rate control system 43 to prevent a decrease in the calorific value of the coal gasified gas fuel.

The air compressor flow control system 43 includes a state quantity detector 40, a calculation controller 41, and an air flow control unit 44 provided at the outlet side of the air compressor 28, and controls the pressure difference between the inside and outside of the dust removal filter. One of the flow rates of the inert gas supplied to the dust filter is detected by the state quantity detector 40, and the detection signal is sent to the operation controller 41, where the operation signal is calculated, and the operation signal is set to a predetermined setting. When a deviation occurs, the operation of the air flow control unit 44 is adjusted based on the deviation, the high-pressure air supplied from the air compressor 28 to the gas turbine combustor 29 is controlled, and the A reduction in the calorific value of the coal gasified gas fuel generated during back washing is prevented.

As described above, in the present embodiment, the air compressor flow control system 43 is provided in the gas turbine plant 18, and the air flow controller 44 is provided at the outlet side of the air compressor 28.
And a calculation signal from the air compressor flow control system 43 is given to the air flow control unit 44 so as to match one of the pressure difference between the inside and outside of the dust filter and the flow rate of the inert gas supplied to the dust filter. Since the operation was adjusted and the high-pressure air supplied from the air compressor 28 to the gas turbine combustor 29 was controlled to prevent the calorific value of the coal gasified gas fuel from decreasing, the calorific value of the coal gasified gas fuel was reduced. It can be supplied to the gas turbine combustor 29 after being stabilized, and the output from the gas turbine 30 can be kept high.

FIG. 3 is a schematic system diagram showing a third embodiment of the coal gasification combined cycle power plant according to the present invention. Note that the same reference numerals are given to the same or corresponding portions as the components of the first embodiment.

In the coal gasification combined cycle power plant according to the present embodiment, a coal gasification gas fuel control system 39 is provided in the gas turbine plant 18 and incorporated in the desulfurization / dust removal device 27 of the coal gasification plant 17 during operation. When back-cleaning the dust removal filter, either one of the pressure difference between the inside and outside of the dust removal filter and the flow rate of the inert gas to be injected and the combustion gas (gas turbine driving gas) generated from the gas turbine combustor 29 are used. Based on the temperature, the calculation is performed by the coal gasification gas fuel control system 30, and the calculation signal is used to control the flow rate of the coal gasification gas fuel supplied from the desulfurization / dust removal device 27 to the gas turbine combustor 29, This is to prevent a decrease in the calorific value of the coal gasified gas fuel.

The coal gasification gas fuel control system 39 includes a state quantity detector 40, an operation controller 41, a fuel controller 42, and a temperature sensor 45 provided at the outlet side of the gas turbine combustor 29.
The state quantity detector 40 detects one of a pressure difference between the inside and outside of the dust removal filter and a flow rate of the inert gas supplied to the dust removal filter, and detects a detection signal of the combustion gas temperature detected by the temperature sensor 45. To the arithmetic and control unit 41,
Here, the calculation is performed, the calculated signal is compared with a predetermined setting signal, and when a deviation occurs, the operation of the fuel control unit 42 is adjusted based on the deviation, and the gas turbine combustor The amount of the clean coal gasification gas fuel supplied to the fuel cell 29 is controlled.

As described above, in the present embodiment, the coal gasification gas fuel control system 39 is provided in the gas turbine plant 18 and the dust filter incorporated in the desulfurization / dust removal device 27 is backwashed with the inert gas. At this time, a coal gasification gas fuel control system 39 is operated based on one of the pressure difference between the inside and outside of the dust removal filter and the flow rate of the inert gas to be charged and the combustion gas temperature generated from the gas turbine combustor 29, The operation signal of the fuel control unit 42 was adjusted by supplying the calculation signal to the fuel control unit 42, and the flow rate of the coal gasification gas fuel was increased by an amount corresponding to the decrease in the calorific value of the coal gasification gas fuel.
Coal gasified gas fuel having a stable calorific value can be supplied to the gas turbine combustor 29, and the output from the gas turbine 30 can be maintained high.

FIG. 4 is a schematic system diagram showing a fourth embodiment of the coal gasification combined cycle power plant according to the present invention. Note that the same reference numerals are given to the same or corresponding portions as the components of the first embodiment.

In the coal gasification combined cycle power plant according to the present embodiment, a combined air / auxiliary fuel control system 47 is provided in the gas turbine plant 18 and is incorporated in the desulfurization / dust removal device 27 of the coal gasification plant 17 during operation. When the dust filter is cleaned in a non-return manner, one of the pressure difference between the inside and outside of the dust filter and the flow rate of the inert gas to be supplied and the temperature of the combustion gas generated from the gas turbine combustor 29 are used. The air / auxiliary fuel combined control system 47 calculates the auxiliary fuel, which is supplied to the gas turbine combustor 29 with the calculation signal, such as kerosene, light oil, residual oil, methanol,
The flow rate of either hydrogen gas or the like and the high-pressure air supplied from the air compressor 28 is controlled to prevent a decrease in the calorific value of the coal gasified gas fuel.

The air / auxiliary fuel combined control system 47 includes a state quantity detector 40, a calculation controller 41, an air flow controller 44 provided on the outlet side of the air compressor 28, and a gas turbine combustor 29.
A temperature sensor 45 provided on the outlet side of the gas turbine combustor 29, and a pressure difference between the inside and outside of the dust filter and the flow rate of the inert gas supplied to the dust filter. One of them is detected by the state quantity detector 40, and the detection signal is sent to the operation controller 41 together with the combustion gas temperature signal from the gas turbine combustor 29 detected by the temperature sensor 45, where the operation signal is calculated. Against a predetermined setting signal, and when a deviation occurs,
The operation of at least one of the auxiliary fuel control unit 46 and the air flow rate control unit 44 is adjusted based on the deviation, and the auxiliary fuel supplied to the gas turbine combustor 29 and the gas turbine combustor 29 Control of at least one of the high-pressure air supplied to the coal gas to prevent a decrease in the calorific value of the coal gasified gas fuel generated at the time of back washing of the dust filter.

As described above, in the present embodiment, the air / auxiliary fuel combined control system 47 is provided in the gas turbine plant 18, the auxiliary fuel control unit 46 is provided in the inlet skin of the gas turbine combustor 29, and the air compressor 28 An air flow control unit 44 is provided on the outlet side of the filter, and the calculation from the combined air / auxiliary fuel control system 47 is performed so as to match one of the pressure difference between the inside and outside of the dust removal filter and the flow rate of the inert gas supplied to the dust removal filter. The signals are transmitted to the auxiliary fuel control unit 46 and the air flow control unit 44.
The operation is adjusted by giving it to at least one of them, and at least one of the auxiliary fuel supplied to the gas turbine combustor 29 and the high-pressure air supplied to the gas turbine combustor 29 from the air compressor 28 Is controlled to prevent a decrease in the calorific value of the coal gasified gaseous fuel, so that the calorific value of the coal gasified gaseous fuel can be stabilized and supplied to the gas turbine combustor 29. The output can be kept high.

[0053]

As described above, in the coal gasification combined cycle power plant according to the present invention, at least one of the fuel control system and the air flow control system is provided in the gas turbine plant, and the fuel control system and the air flow control system are provided. At least one of the air flow control systems controls at least one of fuel and high-pressure air supplied to the gas turbine combustor of the gas turbine plant, and during operation, desulfurization and dedusting of the coal gasification plant Since the reduction of the calorific value of the coal gasified gas fuel generated when the dust filter installed in the device is backwashed with the inert gas is compensated, the stable supply of the calorific value of the coal gasified gas fuel is ensured. Below, the gas turbine output can be maintained high.

[Brief description of the drawings]

FIG. 1 is a schematic system diagram showing a first embodiment of a coal gasification combined cycle power plant according to the present invention.

FIG. 2 is a schematic system diagram showing a second embodiment of a coal gasification combined cycle power plant according to the present invention.

FIG. 3 is a schematic system diagram showing a third embodiment of a coal gasification combined cycle power plant according to the present invention.

FIG. 4 is a schematic system diagram showing a fourth embodiment of a coal gasification combined cycle power plant according to the present invention.

FIG. 5 is a schematic system diagram showing a conventional coal gasification combined cycle power plant.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Coal gasification plant 2 Gas turbine plant 3 Exhaust heat recovery boiler 4 Steam turbine plant 5 Coal supply part 6 Oxygen production device 7 Coal gasification furnace 8 Motor 9 Oxygen production air compressor 10 Cooler 11 Desulfurization / dust removal device 12 Air compressor 13 Gas turbine combustor 14 Gas turbine 15 Generator 16 Heat exchanger 17 Coal gasification plant 18 Gas turbine plant 19 Waste heat recovery boiler 20 Steam turbine plant 21 Coal supply unit 22 Oxygen production device 23 Coal gasifier 24 Motor 25 Air compressor for oxygen production 26 Cooler 27 Desulfurization / dust removal device 28 Air compressor 29 Gas turbine combustor 30 Gas turbine 31 Heat exchanger 32 Steam turbine 33 Generator 34 Condenser 35 Feedwater pump 36 Gas turbine high temperature Part 37 Cooling steam supply system 38 Cooling steam circulation System 39 coal gasification gas fuel control system 40 state amount detector 41 arithmetic and control unit 42 the fuel control unit 43 an air compressor flow control system 44 the air flow control unit 45 temperature sensor 46 auxiliary fuel controller 47 air-assist fuel combination control system

Continuation of the front page (72) Inventor Tatsuro Uchida 1 Toshiba Research and Development Center, Komukai Toshiba-cho, Kawasaki-shi, Kanagawa Prefecture (72) Inventor Shoji Utsunomiya 1-1-1, Shibaura, Minato-ku, Tokyo Inside Toshiba Corporation Head Office (72) Inventor Hiromitsu Iijima 1-1-1, Shibaura, Minato-ku, Tokyo Inside Toshiba Corporation Head Office (72) Inventor Kunihiko Wada 2--4 Suehirocho, Tsurumi-ku, Yokohama-shi, Kanagawa Stock 3G081 BA02 BA13 BB00 BC07 BD00 DA21 DA22

Claims (9)

[Claims] 1. A coal gasification combined cycle power plant that combines a coal gasification plant with a gas turbine plant, an exhaust heat recovery boiler, and a steam turbine plant, is incorporated in a desulfurization / dust removal device of the coal gasification plant. When the dust filter is cleaned, the flow rate of the coal gasified gas fuel is compensated for by reducing the calorific value of the coal gasified gas fuel supplied to the gas turbine combustor of the gas turbine plant from the desulfurization / dust removing device. A coal gasification combined cycle power plant, wherein a coal gasification gas fuel control system for controlling gas is provided in the gas turbine plant. 2. A coal gasification gas fuel control system is operated based on a state quantity detector for detecting a state quantity of a desulfurization / dust removal device of a coal gasification plant and a detection signal from the state quantity detector. An operation controller for operating a fuel control unit provided on the inlet side of a gas turbine combustor of a gas turbine plant based on the deviation when a predetermined setting signal is compared with the operation signal and a deviation is generated. The coal gasification combined cycle power plant according to claim 1, characterized by comprising: 3. A coal gasification gas fuel control system is provided at a state quantity detector for detecting a state quantity of a desulfurization / dust removal device of a coal gasification plant and at an outlet side of a gas turbine combustor of a gas turbine plant. A temperature sensor for detecting the temperature of the combustion gas generated by the gas turbine combustor, and a calculation based on a detection signal from the state quantity detector and a detection signal from the temperature sensor. And a calculation controller for operating a fuel control unit provided on the inlet side of the gas turbine combustor based on the deviation when the set signals are compared with each other. Coal gasification combined cycle power plant. 4. A coal gasification combined cycle power plant that combines a gas turbine plant, a waste heat recovery boiler, and a steam turbine plant with a coal gasification plant, wherein the coal gasification plant is incorporated in a desulfurization and dedusting device of the coal gasification plant. When cleaning the dust filter, the air compressor of the gas turbine plant compensates for the decrease in the calorific value of the coal gasified gas fuel supplied from the desulfurization / dust removal device to the gas turbine combustor of the gas turbine plant. A coal gasification combined cycle power plant, wherein an air compressor flow control system for controlling the flow rate of high-pressure air supplied to the gas turbine combustor from the gas turbine is provided in the gas turbine plant. 5. An air compressor flow control system is operated based on a state quantity detector for detecting a state quantity of a desulfurization / dust removal device of a coal gasification plant, and a detection signal from the state quantity detector, A predetermined setting signal is compared with the operation signal, and when a deviation occurs, the operation controller operates an air flow control unit provided on the outlet side of the air compressor of the gas turbine plant based on the deviation. A coal gasification combined cycle power plant characterized by comprising. 6. A coal gasification combined cycle power plant that combines a coal gasification plant with a gas turbine plant, an exhaust heat recovery boiler, and a steam turbine plant, wherein the coal gasification plant is incorporated in a desulfurization / dust removal device of the coal gasification plant. When the dust filter is cleaned, the desulfurization / dust removal device is supplied to the gas turbine combustor to compensate for a decrease in the calorific value of the coal gasified gas fuel supplied to the gas turbine combustor of the gas turbine plant. An air / auxiliary fuel control system for controlling at least one of the flow rate of auxiliary fuel and the flow rate of high-pressure air supplied from the air compressor of the gas turbine plant to the gas turbine combustor. A coal gas combined cycle power plant, characterized in that it is installed in a coal gas combined cycle power plant. 7. A combined air / auxiliary fuel control system is provided at a state quantity detector for detecting a state quantity of a desulfurization / dust removal device of a coal gasification plant and at an outlet side of a gas turbine combustor of a gas turbine plant. A temperature sensor for detecting the temperature of the combustion gas generated by the gas turbine combustor, and a calculation based on a detection signal from the state quantity detector and a detection signal from the temperature sensor. The auxiliary fuel control unit provided on the inlet side of the gas turbine combustor and the air flow rate provided on the outlet side of the air compressor of the gas turbine plant based on the deviation. 7. The coal gasification combined cycle power plant according to claim 6, wherein the control unit comprises an arithmetic controller that operates at least one of the control units. 8. The state quantity of the desulfurization / dust removal device of the coal gasification plant is one of a pressure difference between the inside and outside of the dust removal filter and a flow rate of an inert gas supplied to the dust removal filter. The coal gasification combined cycle power plant according to claim 2, 3, 5, or 7. 9. A coal gasification combined cycle power plant, wherein the auxiliary fuel is selected from kerosene, light oil, residual oil, methanol and hydrogen gas.