JP2003106514A - Combined power generation plant with coal gasification - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce loads on the environment. SOLUTION: This power generation plant includes plant bodies 2 to 18 for generating electric power by burning synthetic gases derived from gasification of coal, an air separator 21 for separating air into oxygen and nitrogen, and a stack 19 for discharging into the environment a mixture of the combustion products of the synthetic gases and nitrogen, discharged from the plant bodies 2 to 18. The plant bodies 2 to 18 burn the synthetic gases and use gas turbines and steam turbines for combined power generation. By mixing the combustion products with nitrogen, the flow of exhaust released into the atmosphere from the stack 19 is increased while the maximum ground-level concentration of environmentally controlled substances is reduced.

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 generation plant, and more particularly to a coal gasification combined power generation plant for gasifying coal into syngas to extract heat.

[0002]

2. Description of the Related Art It is desired to extract energy from coal with high efficiency. Coal to syngas (carbon monoxide CO
And gasified in the gas mixture) of hydrogen H _2, gas turbines, coal gasification combined cycle power plant for combined power generation using a steam turbine have been developed.

The integrated coal gasification combined cycle power plant 101
Is the coal gasification plant 10 as shown in FIG.
2. A gas purification facility 103, a combined power generation facility 104, and a common facility 105 are provided.

The coal gasification facility 102 comprises a high pressure coal supply system 106, a coal burner 107, a coal gasification furnace 108, a heat exchanger 109, a dedusting facility 110 and a coal / char burner 111. The high-pressure coal supply system 106 pulverizes coal into pulverized coal and mixes the pulverized coal with high-pressure (about 30 K pressure) nitrogen N ₂ which is a carrier medium. Coal burner 10
7 supplies the pulverized coal conveyed by high-pressure nitrogen N ₂ into the coal gasification furnace 108.

[0005] The coal gasification furnace 108 is a cylindrical vessel, and produces syngas by causing a partial combustion reaction of the supplied coal with oxygen O _{2 in a} high pressure atmosphere. The temperature of the produced synthesis gas is about 1100 ° C. Heat exchanger 1
09 cools the produced synthesis gas to about 400 ° C. and supplies it to the dedusting equipment 110. At this time, the heat exchanger 109
The heat recovered by is supplied to the steam turbine 117 and used for power generation.

The dedusting equipment 110 collects char such as unburned carbon C from the produced synthesis gas and mixes the char with high pressure nitrogen N ₂ . The coal / charverner 111
The char transported by high-pressure nitrogen N ₂ is used for coal gasification furnace 10
8, and a predetermined amount of oxygen O ₂ is supplied with respect to the supplied amount of carbon C. The coal gasification furnace 108 burns char in the same manner as pulverized coal and uses it for the production of synthesis gas. The dust removal equipment 110 supplies the syngas from which the char has been removed to the gas purification equipment 103.

The gas refining equipment 103 comprises a desulfurization equipment 112 and a gypsum recovery equipment 113. The sulfur S content derived from coal is contained in the synthesis gas as hydrogen sulfide H ₂ S and COS. The desulfurization facility 112 removes sulfur S content from the synthesis gas. Wet desulfurization is applied as a method for this removal. The gypsum recovery facility 113 mixes the removed sulfur S with calcium carbonate CaCO ₃ and fixes it on the gypsum to recover it. The desulfurization facility 113 supplies the synthetic gas from which the sulfur S content has been removed to the combined power generation facility 104.

The combined power generation facility 104 includes a gas turbine 11
5, an exhaust heat recovery boiler 116, a steam turbine 117, and a generator 118. The combustor 114 of the gas turbine 115 mixes the compressed air with the synthetic gas and combusts it to generate a high temperature and high pressure gas. Gas turbine 115
Rotates the turbine with the high-temperature and high-pressure gas to transmit power to the generator 118. The exhaust heat recovery boiler 116 uses the exhaust gas (waste heat) of the gas turbine 115 to generate high-temperature and high-pressure steam. The steam turbine 117 rotates the turbine using the high-temperature and high-pressure steam generated by the exhaust heat recovery boiler 116 and the heat exchanger 109 to generate a power generator 118.
Transmit power to. The generator 118 uses the supplied power to generate electric power.

The common equipment 105 comprises a chimney 119, an air booster 120 and an air separation device 121. The chimney 119 exhausts combustion products discharged from the integrated coal gasification combined cycle power generation plant 101 into the environment. Air booster 12
0 further compresses the compressed air extracted from the compressor of the gas turbine 115 to generate high pressure air, and supplies the high pressure air to the gasification furnace 108. The air separation device 121 separates air into gaseous oxygen O ₂ and gaseous nitrogen N ₂ . The separated nitrogen N ₂ removes coal and char from the coal gasifier 108.
It is used for transporting to, and for pressure and sealing.
A predetermined amount of oxygen O ₂ with respect to coal is supplied to the coal gasifier 10
8 are supplied.

In a gas turbine combined plant that uses liquefied natural gas as a fuel for power generation, the only environmental regulated substance in the exhaust gas is thermal NO _x produced from nitrogen in the air by high temperature combustion. Synthesis gas produced from coal, ammonia NH _3, contains hydrogen sulfide H _{2 S.} In the exhaust gas of the integrated coal gasification combined cycle power plant, ammonia NO ₃ in the synthesis gas reacts with oxygen O ₂ at a high temperature to produce fuel NO _X , and hydrogen sulfide H ₂ S reacts with oxygen O _2. The generated SO _X and the soot and dust exemplified by the suspended particulate matter are contained. Therefore, the integrated coal gasification combined cycle power plant needs more advanced environmental measures.

[0011]

An object of the present invention is to provide an integrated coal gasification combined cycle power plant that reduces the load on the environment. Another object of the present invention is to provide an integrated coal gasification combined cycle power plant that reduces environmental pollution. Yet another object of the present invention is to provide a combined coal gasification combined cycle power generation plant that reduces the maximum landing concentration of substances subject to environmental regulations.

[0012]

[Means for Solving the Problems] Means for solving the problems will be described below by using the numbers and symbols used in the embodiments of the present invention. These numbers and signs are added to clarify the correspondence between the description in [Claims] and the description in [Embodiments of the invention], and are described in [Claims]. It should not be used to interpret the technical scope of the claimed invention.

The integrated coal gasification combined cycle power generation plant (1, 31, 41) according to the present invention produces a diluted gas and a plant body (2-18) for combusting syngas produced by gasifying coal to produce electric power. A dilution gas supply device (30, 21),
It is provided with a chimney (19) for discharging to the environment a mixture of combustion products of synthesis gas and diluent gas discharged from the plant body (2-18).

The synthesis gas contains carbon monoxide CO and hydrogen H ₂ . The plant body (2 to 18) burns syngas and uses gas turbines and steam turbines to perform combined power generation. The synthesis gas contains ammonia NH ₃ and hydrogen sulfide H ₂ S, and the combustion products exhausted by the plant body (2 to 18) are NO _X and SO which are environmental regulated substances.
_X contains soot and dust. Diluting gas supply device (30,
The diluent gas generated in 21) does not substantially contain the environmentally controlled substance. By mixing the combustion products with the diluent gas, the flow rate of the exhaust gas discharged from the chimney (19) to the environment is increased and the maximum landing concentration of the environmentally regulated substance is decreased.

The oxygen O ₂ content of the diluent gas is preferably smaller than the oxygen O ₂ content of the air.

The dilution gas supply device is an air separation device (21) for separating air into oxygen O ₂ and nitrogen N ₂ . The plant body (2-18) produces synthesis gas from coal using oxygen O ₂ . The diluent gas supplied to the chimney (19) is preferably nitrogen N ₂ .

The integrated coal gasification combined cycle power plant (41) according to the present invention is further provided between the dilution gas supply device (21) and the chimney (19) to heat the dilution gas and supply it to the chimney. It is equipped with a container (43, 45). By heating the diluent gas, the maximum landing concentration of environmentally regulated substances is further reduced.

The air separating device (21) exchanges heat between the compressed air and the dilution gas and the air compressor (42) for compressing the air to generate the compressed air to cool the compressed air. A heat exchanger (43) for heating the diluted gas and an air separation device body (44) for separating the cooled compressed air into oxygen O ₂ and nitrogen N ₂ are provided. The heater is a heat exchanger (4
Including 3). With such a heater, the amount of heat for heating the diluent gas can be saved.

The heater further includes a preheater (45) for further heating the diluent gas heated by the heat exchanger (43). The pre-heater (45) heats the diluent gas to a sufficient temperature when the heating of the diluent gas by the heat exchanger (43) is insufficient.

The temperature of the diluent gas supplied to the chimney (19) is preferably higher than the temperature of the combustion products. Such a diluent gas does not reduce the flow rate and temperature of the exhaust gas of the chimney (19), and further reduces the maximum landing concentration of the environmentally regulated substance.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of an integrated coal gasification combined cycle power plant according to the present invention will be described with reference to the drawings. As shown in FIG. 1, the integrated coal gasification combined cycle power generation plant 1 includes coal gasification equipment 2, gas purification equipment 3, combined power generation equipment 4 and common equipment 5.

The coal gasification facility 2 comprises a high pressure coal supply system 6,
A coal burner 7, a coal gasifier 8, a heat exchanger 9, a dedusting facility 10 and a coal / char burner 11 are provided. The high-pressure coal supply system 6 pulverizes coal into pulverized coal and mixes the pulverized coal with high-pressure (about 30 K pressure) nitrogen N ₂ which is a carrier medium. The coal burner 7 supplies the pulverized coal transported by high-pressure nitrogen N ₂ into the coal gasification furnace 8.

The coal gasifier 8 is a cylindrical container,
Syngas is produced by partially reacting the supplied coal with oxygen O _{2 in a} high pressure atmosphere. The temperature of the produced synthesis gas is about 1100 ° C. The heat exchanger 9 is
The produced synthesis gas is cooled to about 400 ° C. and supplied to the dedusting equipment 10. At this time, the heat recovered by the heat exchanger 9 is supplied to the steam turbine 17 and used for power generation.

The dedusting equipment 10 collects char such as unburned carbon C from the produced synthesis gas and mixes the char with high-pressure nitrogen N ₂ . The coal / char burner 11 supplies the char carried by the high-pressure nitrogen N ₂ to the coal gasification furnace 8, and further supplies a predetermined amount of gaseous oxygen O _{2 with} respect to the supplied amount of carbon C. The coal gasification furnace 8 burns char in the same manner as pulverized coal and uses it for the generation of synthesis gas. The dedusting equipment 10 supplies the char-removed synthesis gas to the gas purification equipment 3.

The gas refining facility 3 comprises a desulfurization facility 12 and a gypsum recovery facility 13. The sulfur S content derived from coal is contained in the synthesis gas as hydrogen sulfide H ₂ S and COS. The desulfurization facility 12 removes the sulfur S content from the synthesis gas. Wet desulfurization is applied as a method for this removal.
The gypsum recovery facility 13 mixes the removed sulfur S with calcium carbonate CaCO ₃ and fixes it on the gypsum to recover it. The desulfurization facility 13 supplies the combined gas power generation facility 4 with the synthesis gas from which the sulfur S content has been removed.

The combined power generation facility 4 includes a gas turbine 15, an exhaust heat recovery boiler 16, a steam turbine 17 and a generator 18.
Is equipped with. The combustor 14 of the gas turbine 15 mixes the compressed air with the synthesis gas and combusts it to generate a high temperature and high pressure gas. The gas turbine 15 rotates the turbine with the high-temperature and high-pressure gas to transmit power to the generator 18. The exhaust heat recovery boiler 16 uses the exhaust gas (waste heat) of the gas turbine 15 to generate high-temperature and high-pressure steam. The steam turbine 17 rotates the turbine using the high-temperature and high-pressure steam generated by the exhaust heat recovery boiler 16 to transmit power to the generator 18. The generator 18 uses the supplied power to generate electric power.

The common equipment 6 includes a chimney 19 and an air booster 2.
0, an air separation device 21 and a dilution gas supply device 30. The air booster 20 further compresses the gas extracted from the gas turbine 15 to generate high pressure air, and supplies the high pressure air to the gasification furnace 8. The air separation device 21 separates air taken in from the environment into gaseous oxygen O ₂ and gaseous nitrogen N ₂ . The separated nitrogen N ₂ is used for transporting coal and char to the coal gasification furnace 8 and for pressurizing and sealing. A predetermined amount of oxygen O ₂ is supplied to the coal gasification furnace 8 with respect to coal.

The diluting gas supply device 30 supplies the chimney 19 with a diluting gas which is a gas containing no environmentally regulated substance. Such dilution gas, nitrogen N ₂ and the like, the gas content of the oxygen O ₂ is less than the content of oxygen O ₂ in the air is preferred. The chimney 19 is a dilution gas supply device 3
The dilution gas supplied from 0 and the combustion products discharged from the exhaust heat recovery boiler 16 are mixed and exhausted into the environment.

The combined power generation facility 4 burns the synthetic gas produced from coal to generate electricity, and exhausts the combustion product of the synthetic gas. The synthesis gas is ammonia NH derived from coal.
₃ , containing hydrogen sulfide H ₂ S. The combustion product has a temperature of 100 ° C. to 150 ° C. and contains an environmentally controlled substance. Examples of the substance include fuel NO _x produced by reacting ammonia NH ₃ in the synthesis gas with oxygen O ₂ at high temperature, SO _x produced by reacting hydrogen sulfide H ₂ S with oxygen O ₂ , and soot. Dust (soot) is exemplified.

The environmentally regulated substance is mixed with the diluting gas and released into the environment through the chimney 19. The landing concentration, which indicates the concentration of environmentally regulated substances on the ground, is low near the chimney 19 because the exhaust gas does not fall to the surface of the earth, and gradually increases as the distance increases, and further away after reaching the maximum landing concentration It becomes smaller by diffusion. The maximum landing concentration is expressed as a function of the flow rate of exhaust gas discharged from the chimney 19 and the temperature. That is, the maximum landing concentration is
The smaller the flow rate of exhaust gas, the smaller it becomes, and the higher the temperature of exhaust gas becomes, the smaller it becomes.

The integrated coal gasification combined cycle power plant according to the present invention increases the flow rate of the exhaust gas discharged from the stack by mixing the combustion products discharged from the combined cycle power generation plant 4 with the diluent gas and discharging the mixed gas from the stack. Reduce the maximum landing concentration of environmentally controlled substances.

FIG. 2 shows another embodiment of the integrated coal gasification combined cycle power plant according to the present invention. The integrated coal gasification combined cycle power generation plant 31 includes a coal gasification equipment 2, a gas refining equipment 3, an integrated generation equipment 4 and a common equipment 5.

The coal gasification facility 2 comprises a high pressure coal supply system 6,
A coal burner 7, a coal gasifier 8, a heat exchanger 9, a dedusting facility 10 and a coal / char burner 11 are provided. The high-pressure coal supply system 6 pulverizes coal into pulverized coal and mixes the pulverized coal with high-pressure (about 30 K pressure) nitrogen N ₂ which is a carrier medium. The coal burner 7 supplies the pulverized coal transported by high-pressure nitrogen N ₂ into the coal gasification furnace 8.

The coal gasifier 8 is a cylindrical vessel,
Syngas is produced by partially reacting the supplied coal with oxygen O _{2 in a} high pressure atmosphere. The temperature of the produced synthesis gas is about 1100 ° C. The heat exchanger 9 is
The produced synthesis gas is cooled to about 400 ° C. and supplied to the dedusting equipment 10. At this time, the heat recovered by the heat exchanger 9 is supplied to the steam turbine 17 and used for power generation.

The dedusting equipment 10 collects char such as unburned carbon C from the produced syngas and mixes the char with high-pressure nitrogen N ₂ . The coal / char burner 11 supplies the char carried by the high-pressure nitrogen N ₂ to the coal gasification furnace 8, and further, a predetermined oxygen O for the supplied carbon C amount.
Supply ₂ volumes. The coal gasification furnace 8 burns char in the same manner as pulverized coal and uses it for the generation of synthesis gas. The dedusting equipment 10 is a gas purification equipment 3 for the syngas from which the char has been removed.
Supply to.

The gas refining facility 3 comprises a desulfurization facility 12 and a gypsum recovery facility 13. The sulfur S content derived from coal is contained in the synthesis gas as hydrogen sulfide H ₂ S and COS. The desulfurization facility 12 removes the sulfur S content from the synthesis gas. Wet desulfurization is applied as a method for this removal.
The gypsum recovery facility 13 mixes the removed sulfur S with calcium carbonate CaCO ₃ and fixes it on the gypsum to recover it. The desulfurization facility 13 supplies the combined gas power generation facility 4 with the synthesis gas from which the sulfur S content has been removed.

The combined power generation facility 4 includes a gas turbine 15, an exhaust heat recovery boiler 16, a steam turbine 17 and a generator 18.
Is equipped with. The combustor 14 of the gas turbine 15 mixes the compressed air with the synthesis gas and combusts it to generate a high temperature and high pressure gas. The gas turbine 15 rotates the turbine with the high-temperature and high-pressure gas to transmit power to the generator 18. The exhaust heat recovery boiler 16 uses the exhaust gas (waste heat) of the gas turbine 15 to generate high-temperature and high-pressure steam. The steam turbine 17 includes the exhaust heat recovery boiler 16 and the heat exchanger 9
The turbine is rotated by using the high-temperature and high-pressure steam generated by the above, and power is transmitted to the generator 18. The generator 18
Electric power is generated using the supplied power.

The common equipment 6 includes a chimney 19 and an air booster 20.
And an air separation device 21. Air booster 20
Supplies the compressed air extracted from the gas turbine 15 to the coal / char burner 11. The air separation device 21 separates air taken in from the environment into gaseous oxygen O ₂ and gaseous nitrogen N ₂ . A predetermined amount of oxygen O ₂ is supplied to the coal gasification furnace 8 with respect to coal. The separated nitrogen N ₂ is supplied to the coal burner 7 and the coal / char burner 11 for transporting coal and char to the coal gasifier 8, and is also supplied to the chimney 19 as a diluent gas. The chimney 19 includes the dilution gas supplied from the air separation device 21 and the exhaust heat recovery boiler 16
It is mixed with the combustion products emitted from the exhaust gas and discharged into the environment.

The combined power generation facility 4 burns the synthetic gas produced from coal to generate electricity, and exhausts the combustion product of the synthetic gas. The combustion product has a temperature of 100 ° C. to 150 ° C. and contains a trace amount of environmentally regulated substances. The environmentally regulated substance is mixed with the diluting gas and released from the chimney 19 into the environment as exhaust gas.

Included in the exhaust emitted from the chimney 19 to the environment
The concentration of environmentally regulated substances is regulated. The present invention
Coal gasification combined cycle power plant by
Elementary N _TwoOf the exhaust emitted into the environment by diluting with
The concentration of environmentally regulated substances can be reduced.

FIG. 3 shows still another embodiment of the integrated coal gasification combined cycle power plant according to the present invention. The integrated coal gasification combined cycle power plant 41 includes the coal gasification facility 2,
A gas refining facility 3, a combined power generation facility 4 and a common facility 5 are provided.

The coal gasification facility 2 comprises a high pressure coal supply system 6,
A coal burner 7, a coal gasifier 8, a heat exchanger 9, a dedusting facility 10 and a coal / char burner 11 are provided. The high-pressure coal supply system 6 pulverizes coal into pulverized coal and mixes the pulverized coal with high-pressure (about 30 K pressure) nitrogen N ₂ which is a carrier medium. The coal burner 7 supplies the pulverized coal transported by high-pressure nitrogen N ₂ into the coal gasification furnace 8.

The coal gasifier 8 is a cylindrical vessel,
Syngas is produced by partially reacting the supplied coal with oxygen O _{2 in a} high pressure atmosphere. The temperature of the produced synthesis gas is about 1100 ° C. The heat exchanger 9 is
The produced synthesis gas is cooled to about 400 ° C. and supplied to the dedusting equipment 10. At this time, the heat recovered by the heat exchanger 9 is supplied to the steam turbine 17 and used for power generation.

The dedusting equipment 10 collects char such as unburned carbon C from the produced syngas and mixes the char with high-pressure nitrogen N ₂ . The coal / char burner 11 supplies the char carried by the high-pressure nitrogen N ₂ to the coal gasification furnace 8, and further, a predetermined oxygen O for the supplied carbon C amount.
Supply ₂ volumes. The coal gasification furnace 8 burns char in the same manner as pulverized coal and uses it for the generation of synthesis gas. The dedusting equipment 10 is a gas purification equipment 3 for the syngas from which the char has been removed.
Supply to.

The gas refining equipment 3 comprises a desulfurization equipment 12 and a gypsum recovery equipment 13. The sulfur S content derived from coal is contained in the synthesis gas as hydrogen sulfide H ₂ S and COS. The desulfurization facility 12 removes the sulfur S content from the synthesis gas. Wet desulfurization is applied as a method for this removal.
The gypsum recovery facility 13 mixes the removed sulfur S with calcium carbonate CaCO ₃ and fixes it on the gypsum to recover it. The desulfurization facility 13 supplies the combined gas power generation facility 4 with the synthesis gas from which the sulfur S content has been removed.

The combined power generation facility 4 includes a gas turbine 15, an exhaust heat recovery boiler 16, a steam turbine 17 and a generator 18.
Is equipped with. The combustor 14 of the gas turbine 15 mixes the compressed air with the synthesis gas and combusts it to generate a high temperature and high pressure gas. The gas turbine 15 rotates the turbine with the high-temperature and high-pressure gas to transmit power to the generator 18. The exhaust heat recovery boiler 16 uses the exhaust gas (waste heat) of the gas turbine 15 to generate high-temperature and high-pressure steam. The steam turbine 17 includes the exhaust heat recovery boiler 16 and the heat exchanger 9
The turbine is rotated by using the high-temperature and high-pressure steam generated by the above, and power is transmitted to the generator 18. The generator 18
Electric power is generated using the supplied power.

The common equipment 6 includes a chimney 19 and an air booster 2.
0, an air separation device 21 and a heater 45.
The air booster 20 further compresses the compressed air extracted from the gas turbine 15 to generate high pressure air, and supplies the high pressure air to the coal / char burner 11.

The air separation device 21 comprises an air compressor 42, a heat exchanger 43 and an air separation device body 44.
The air compressor 42 compresses air to generate compressed air. The temperature of this compressed air rises due to adiabatic compression and becomes high. The heat exchanger 43 transfers heat between the cold nitrogen N ₂ generated by the air separation device body 44 and the compressed air to cool the compressed air and heat the nitrogen N ₂ . The heated nitrogen N ₂ is supplied to the heater 45. The air separation device body 44 adiabatically expands the compressed air, liquefies it, and then rectifies it to separate it into nitrogen N ₂ and oxygen O ₂ . Oxygen separated
₂ is supplied to the coal / char burner 11, and a predetermined amount of coal is supplied to the coal gasification furnace 8. The separated nitrogen N ₂ is supplied to the coal burner 7 and the coal / char burner 11 to convey coal and char to the coal gasifier 8. The surplus nitrogen is supplied to the heat exchanger 43 as cold nitrogen N ₂ .

The heater 45 heats the supplied nitrogen N ₂ to a temperature equal to or higher than the temperature of the combustion products discharged from the exhaust heat recovery boiler 16 and supplies it to the chimney 19. The chimney 19 is a heater 45.
The nitrogen N ₂ supplied from the exhaust gas and the combustion product discharged from the exhaust heat recovery boiler 16 are mixed and exhausted into the environment.

The combined power generation facility 4 burns the synthetic gas produced from coal to generate electricity, and exhausts the combustion product of the synthetic gas. The combustion product has a temperature of 100 ° C. to 150 ° C. and contains a trace amount of environmentally regulated substances. The environmentally regulated substance is mixed with the diluting gas and released from the chimney 19 into the environment as exhaust gas.

The landing concentration, which indicates the concentration of environmentally regulated substances on the ground, is low near the chimney 19 because the exhaust gas does not fall to the ground surface, and gradually increases as the distance increases, and further reaches the maximum landing concentration. In the distance, it gradually becomes smaller due to diffusion. The maximum landing concentration is expressed as a function of the flow rate of exhaust gas discharged from the chimney 19 and the temperature.
That is, the maximum landing concentration decreases as the flow rate of exhaust gas increases and decreases as the exhaust gas temperature increases.

In the integrated coal gasification combined cycle power plant according to the present invention, the combustion products discharged from the combined cycle power generation facility 4 are mixed with the heated gaseous nitrogen N ₂ and discharged from the chimney, so that the combustion discharged from the chimney. It increases the exhaust flow rate without decreasing the product temperature and reduces the maximum landing concentration of environmentally regulated substances. Further, in the integrated coal gasification combined cycle power plant according to the present invention, the concentration of the environmentally regulated substance in the exhaust gas released to the environment can be reduced by diluting the combustion product with nitrogen N ₂ .

[0053]

The integrated coal gasification combined cycle power plant according to the present invention can reduce the load on the environment.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of an integrated coal gasification combined cycle power plant according to the present invention.

FIG. 2 is a block diagram showing another embodiment of the integrated coal gasification combined cycle power plant according to the present invention.

FIG. 3 is a block diagram showing still another embodiment of the integrated coal gasification combined cycle power plant according to the present invention.

FIG. 4 is a block diagram showing an embodiment of a known integrated coal gasification combined cycle power plant.

[Explanation of symbols]

1: Integrated coal gasification combined cycle power plant 2: Coal gasification equipment 3: Gas purification equipment 4: Complex power generation facility 5: Common equipment 6: High pressure coal supply system 7: Coal burner 8: Coal gasification furnace 9: Heat exchanger 10: Dust removal equipment 11: Coal / Chevron 12: Desulfurization equipment 13: Gypsum recovery equipment 14: Combustor 15: Gas turbine 16: Exhaust heat recovery boiler 17: Steam turbine 18: Generator 19: Chimney 20: Air booster 21: Air separation device 30: Diluting gas supply device

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ identification code FI theme code (reference) F02C 6/18 F02C 7/00 B 7/00 F23L 7/00 A F23L 7/00 F25J 3/02 A F25J 3/02 3/04 101 3/04 101 F23J 15/00 C (72) Inventor Saiomi Yoshiomi 2-5-1, Marunouchi, Chiyoda-ku, Tokyo Sanryo Heavy Industries Co., Ltd. F-term (reference) 3G081 BA02 BA13 BB00 BC07 DA21 3K023 JA01 3K070 DA01 DA02 DA03 DA07 DA23 DA27 DA47 DA49 4D047 AA08 AB01 AB02 BA01 CA03 CA15 DA03 DB05

Claims (7)

[Claims] 1. A plant body for combusting syngas produced by gasifying coal to generate electricity, a dilution gas supply device for producing a dilution gas, a combustion product of the synthesis gas discharged from the plant body, and the dilution. A coal gasification combined cycle power plant comprising a chimney that discharges a mixture with a gas to the environment. _2. The integrated coal gasification combined cycle power generation plant according to claim 1, wherein the oxygen O ₂ content of the diluent gas is smaller than the oxygen O ₂ content of the air. 3. The dilution gas supply device according to claim 2, wherein the dilution gas supply device is an air separation device that separates air into oxygen O ₂ and nitrogen N ₂ , and the plant body uses the oxygen O ₂ for the coal. to produce synthesis gas from the dilution gas, coal gasification combined cycle power plant which is the nitrogen N _2. 4. The integrated coal gasification combined cycle power generation according to claim 3, further comprising a heater which is interposed between the dilution gas supply device and the chimney to heat the dilution gas and supply the diluted gas to the chimney. plant. 5. The air separation device according to claim 4, wherein the air compressor compresses air to generate compressed air, and exchanges heat between the compressed air and the diluent gas, A heat exchanger that cools the compressed air and heats the dilution gas; and the cooled compressed air to the oxygen O ₂ and the nitrogen N _2.
And a main body of an air separation device that separates the heat exchanger into a unit, wherein the heater includes the heat exchanger. 6. The integrated coal gasification combined cycle power plant according to claim 5, wherein the heater further includes a preheater that further heats the dilution gas heated by the heat exchanger. 7. The integrated coal gasification combined cycle power plant according to claim 1, wherein the temperature of the dilution gas supplied to the chimney is equal to or higher than the temperature of the combustion products.