JP6957198B2 - Gasification furnace equipment and gasification combined cycle equipment equipped with this - Google Patents

Description

The present invention relates to a gasification furnace facility provided with a char transfer system for returning the char separated from the produced gas to the gasification furnace, and a gasification combined cycle facility equipped with the char transfer system.

The gasification furnace facility for gasifying pulverized coal (carbon-containing solid fuel) is equipped with a char transport system that returns the char separated from the produced gas obtained by gasifying the pulverized coal to the main body of the gasification furnace. It has been proposed that a generated gas is used to airflow the char through the char transport system (see Patent Document 1).

Japanese Unexamined Patent Publication No. 2000-328874

When the generated gas is used as the fluid for carrying the char in the air flow as in Patent Document 1, it is not necessary to use the nitrogen separated by the air separation equipment (ASU), so that there is an advantage that the power of the air separation equipment can be reduced.

However, the produced gas contains a corrosive component, and in Patent Document 1, since the produced gas is used for char transport without removing the corrosive component from the generated gas discharged from the water scrubber, the piping and valves of the char transport system are used. May corrode the kind.

The present invention has been made in view of such circumstances, and includes a gasification furnace facility capable of avoiding corrosion of the char transport system even when a generated gas is used for char transport, and a gasification furnace facility thereof. The purpose is to provide gasification combined cycle equipment.

In order to solve the above problems, the gasification furnace equipment of the present invention and the gasification combined cycle equipment provided with the gasification furnace equipment adopt the following means.
That is, the gasifier equipment according to the present invention includes a gasifier main body that gasifies carbon-containing solid fuel, a char separator that separates char from the generated gas generated in the gasifier main body, and the char. A char transport system that transports the char separated by the separator to the gasifier main body, a corrosive gas removing means that removes corrosive gas from the generated gas that separates the char by the char separator, and the corrosion. It is characterized by including a char transport gas supply system that guides a part of the generated gas from which the corrosive gas is separated by the sex gas removing means to the char transport system.

When guiding the char to the main body of the gasification furnace, the generated gas is used as a transport medium. As the produced gas used as the char transport medium, it was decided to use the produced gas from which the corrosive gas was removed. As a result, it is possible to prevent the pipes and valves of the char transport system from being corroded by the corrosive gas.
Examples of the corrosive gas include H ₂ S contained in the produced gas.
Since nitrogen is not required as the char transport medium, the capacity of the air separation device (ASU) can be reduced. As a result, the equipment cost of the air separation device (ASU) can be reduced. In addition, the power of the air separation device (ASU) can be reduced, and the efficiency of the plant can be expected to improve.

Further, the gasification furnace equipment of the present invention is characterized in that a generated gas having a temperature of 100 ° C. or higher is introduced into the char transport gas supply system.

Since it was decided to guide the generated gas having a temperature of 100 ° C. or higher to the char transport gas supply system and to guide the generated gas having a relatively high temperature in advance to the char transport gas supply system, a heating means such as a heat exchanger was introduced to the char transport gas supply system. The capacity can be reduced or the heating means can be removed even when the above is provided.

Further, the gasification furnace equipment of the present invention is characterized by including a product gas temperature adjusting means for adjusting the temperature of the product gas led to the char transport gas supply system.

The temperature of the produced gas can be set to a desired value of 100 ° C. or higher by the produced gas temperature adjusting means for adjusting the temperature of the produced gas led to the char transport gas supply system.
Examples of the produced gas temperature adjusting means include a control valve that controls the pressure and flow rate of the cooling medium supplied to the heat exchanger that cools the produced gas led from the char separator.

Further, in the gasification furnace equipment of the present invention, the generated gas temperature adjusting means is provided between the char separator and the corrosive gas removing means, and the generated gas and the cooling medium separated by the char separator are provided. preparative characterized in that it is a gas cooler for heat exchange.

For example, when a gas gas heater (GGH) is used, the temperature of the generated gas cannot be controlled unless a bypass line is provided. In addition, the provision of a bypass line affects cost increase and space design. On the other hand, if a gas cooler is used, the temperature can be controlled by adjusting the pressure and flow rate of the cooling medium (for example, steam) supplied to the gas cooler, and the bypass line becomes unnecessary.

Further, the gasification combined power generation facility of the present invention is provided by the gasification furnace facility according to any one of the above, a gas turbine driven by using the generated gas derived from the gasification furnace facility, and the gas turbine. It is characterized by having a driven generator.

Since the generated gas from which the corrosive gas has been removed is used as the char transport gas, it is possible to prevent the char transport system from being corroded by the corrosive gas.

It is a schematic block diagram which showed the gasification combined cycle power generation facility which concerns on one Embodiment of this invention.

Hereinafter, embodiments according to the present invention will be described with reference to the drawings.
FIG. 1 shows a schematic configuration of a gasification combined cycle facility to which the gasification furnace facility according to the embodiment of the present invention is applied.

The integrated gasification combined cycle (IGCC) 1 includes a gasification furnace facility 3. The gasifier facility 3 uses only air or air and oxygen as oxidants, and employs an air combustion method that generates flammable gas from a carbon-containing solid fuel such as coal. The gasification combined power generation facility 1 purifies the generated gas generated by the gasification furnace facility 3 into a fuel gas by the gas purification facility 5, and then supplies the gas to the gas turbine 7 to generate electricity. That is, the gasification combined cycle facility 1 is an air combustion type (air blown) power generation facility. In addition, instead of air blowing, oxygen blowing gasification combined cycle equipment may be used. As the carbon-containing solid fuel supplied to the gasifier facility 3, for example, coal is used.

The gasification complex power generation facility 1 includes a gasifier facility 3, a gas purification facility 5, a gas turbine 7, a steam turbine 18, a generator 19, and a heat recovery steam generator (HRSG) 20. It has.

The gasifier facility 3 includes a coal supply facility 9. The coal supply facility 9 supplies coal, which is a carbon-containing solid fuel, as raw coal from the coal supply bunker 12, and crushes the coal with a coal mill 13 to produce pulverized coal pulverized into fine particles. The pulverized coal produced in the coal mill 13 is temporarily stored in the pulverized coal bottle 17, and is used as an inertia gas for transportation supplied from each pulverized coal supply hopper 14 via a coal supply line 15 and from an air separation facility (ASU) 42. It is pressurized by nitrogen gas and supplied to the gasifier facility 3. The Inert gas is an inert gas having an oxygen content of about 5% by volume or less, and nitrogen gas, carbon dioxide gas, argon gas and the like are typical examples, but it is not necessarily limited to about 5% or less.

The gasifier facility 3 is supplied with pulverized coal produced by the coal supply facility 9, and the char (unreacted coal and ash) recovered by the char recovery facility 11 is supplied for reuse. There is.

A compressed air supply line 41 is connected to the gas turbine equipment 3 from the compressor 61 of the gas turbine 7, and a part of the compressed air compressed by the compressor 61 is boosted to a predetermined pressure by the booster 68. It can be supplied to the gasification furnace 16.

The air separation facility 42 separates and generates nitrogen and oxygen from the air in the atmosphere, and the air separation facility 42 and the gasifier facility 3 are connected by a nitrogen supply line 43. A coal supply line 15 from the coal supply facility 9 is connected to the nitrogen supply line 43. The air separation equipment 42 is connected to the compressed air supply line 41 by an oxygen supply line 47.

The nitrogen separated by the air separation equipment 42 is used as a gas for transporting pulverized coal by flowing through the nitrogen supply line 43. Further, the oxygen separated by the air separation facility 42 is used as an oxidant in the gasifier facility 3 by flowing through the oxygen supply line 47 and the compressed air supply line 41.

The gasifier equipment 3 includes, for example, a two-stage jet bed type gasifier 16. The gasification furnace facility 3 gasifies the coal (pulverized coal) and char supplied to the inside by partially burning them with an oxidizing agent (air, oxygen) to obtain a produced gas. The gasification furnace 16 includes a gasification furnace main body 16a and a pressure vessel 16b that houses the gasification furnace main body 16a inside and holds a pressurized state. The inside of the gasification furnace main body 16a is set to, for example, 3 to 4 MPa (gauge pressure).

The burners 30 and 31 are provided in two upper and lower stages. A convertor portion 32 is provided at a position corresponding to the lower burner 30, and supplies _{heat for gasification, CO 2} and H _{2 O by burning a part of pulverized coal and / or char.} .. A reducer portion 33 is provided at a position corresponding to the upper burner 31, and gasifies the pulverized coal.

A thin gas cooler 35 as a gas cooler is provided on the downstream side of the reducer portion 33, and the generated gas is cooled to a predetermined temperature before being supplied to the char recovery equipment (char separator) 11. Steam is generated in the singus cooler 35, and the generated steam is guided to the exhaust heat recovery boiler 20.

A production gas line 49 for supplying generated gas to the char recovery equipment 11 is connected to the gasification furnace facility 3, and the generated gas containing the char can be discharged.

The char collection facility 11 includes a dust collector 51 and a plurality of char supply hoppers 52. In this case, the dust collecting facility 51 is composed of one or more cyclones or porous filters, and can recover the char contained in the generated gas generated by the gasifier facility 3. Then, the generated gas from which the char is separated is sent to the gas refining facility 5 through the gas discharge line 53.

The char supply hopper 52 stores the char recovered from the generated gas in the dust collector 51. A char bin 54 is arranged between the dust collector 51 and the char supply hopper 52. A plurality of char supply hoppers 52 are connected to the char bin 54, respectively. The char return line 46 from the char supply hopper 52 is connected to the char transfer system 45.

The gas refining facility 5 purifies the produced gas from which the char is separated by the char recovery facility 11 by removing impurities such as sulfur compounds and nitrogen compounds.
The gas refining facility 5 purifies the produced gas to produce a fuel gas, which is supplied to the gas turbine 7. Since the produced gas from which the char is separated still _{contains sulfur (H 2} S, etc.), the gas refining facility 5 removes and recovers the sulfur content with an amine absorbing liquid or the like, and effectively uses it.

Gas purification equipment 5, the first heat exchanger 21, COS converter 22, a gas cooler 23, the second heat exchanger 24, cooling the washing tower 25, _{H 2} S absorption tower (corrosive gas removing means) 26 ..

Product gas led from the dust collector 51 is reduced temperature by heat exchange in the first heat exchanger 21, COS in the product gas at COS converter 22 (carbonyl sulfide) to H _{2 S} by catalytic Convert. After that, the generated gas is guided to the gas cooler 23 and exchanges heat with the boiler water supply (BFW) which is a cooling medium to be cooled. The boiler supply water (BFW) heated by the gas cooler 23 is supplied to the exhaust heat recovery boiler 20.
The gas cooler 23 is a kettle type heat exchanger. The pressure of the boiler water supply (BFW) led to the gas cooler 23 is adjusted by a pressure control valve (produced gas temperature adjusting means) 27 controlled by a control unit (not shown). That is, by controlling the opening degree of the pressure control valve 27, the cooling amount of the produced gas in the gas cooler 23 is adjusted, and the temperature of the produced gas is controlled. When the gas cooler 23 is a shell & tube type heat exchanger, the cooling amount of the generated gas is adjusted by controlling the flow rate of the boiler supply water (BFW).

The generated gas cooled by the gas cooler 23 is further cooled by the second heat exchanger 24. Then, the generated gas is cooled and washed with cooling water in the cooling and washing tower 25, and then _{H 2} S is removed in _{the H 2} S absorption tower 26. The _{generated gas from which H 2 S has been removed by the H 2} S absorption tower 26 passes through the refined gas supply line 28 and is heated by the second heat exchanger 24 and the first heat exchanger 21, and then the gas turbine 7 It is led to the combustor 62 of.

The refined gas supply line 28 is connected to the upstream end 48a of the char transport gas supply system 48 that takes out a part of the generated gas. The upstream end 48a is provided between the first heat exchanger 21 and the second heat exchanger 24. However, the upstream end 48a is not limited to this position, and may be another position on the refined gas supply line 28 as long as the temperature of the produced gas is 100 ° C. or higher.

A syngas compressor 36 is provided in the char transport gas supply system 48. The syngas compressor 36 is driven by an electric motor 36M and is operated at a predetermined rotation speed by a control unit (not shown). The heat of compression in the syngas compressor 36 raises the temperature of the produced gas to a desired value. That is, the generated gas temperature at the upstream end 48a of the char transport gas supply system 48 is determined in consideration of the heat of compression of the syngas compressor 36 so as to satisfy the temperature required by the gasifier equipment 3. The generated gas compressed by the syngas compressor 36 is guided to the char transport system 45 as the char transport gas via the char transport gas supply system 48, and the char guided from the char return line 46 is gasified into the gasifier equipment. Lead to 3.

A start-up nitrogen supply line 37 is connected to the char transport gas supply system 48 at a connection position 48b on the downstream side of the syngas compressor 36. The start-up nitrogen supply line 37 is used to transport the char at the start of the gasifier equipment 3 when the generated gas is not sufficiently generated for the char transport. A liquid nitrogen tank 40, a vaporizer 39 for vaporizing liquid nitrogen, and a nitrogen compressor 38 for pressurizing the vaporized nitrogen are provided on the upstream side of the nitrogen supply line 37 at startup.

The gas turbine 7 includes a compressor 61, a combustor 62, and a turbine 63, and the compressor 61 and the turbine 63 are connected by a rotating shaft 64. A compressed air supply line 65 from the compressor 61 is connected to the combustor 62, and a fuel gas supply line 66 to which the refined gas supply line 28 of the gas purification facility 5 is connected is connected. A combustion gas supply line 67 that supplies combustion gas to the turbine 63 is connected to the combustor 62.
The gas turbine 7 is provided with a compressed air supply line 41 extending from the compressor 61 to the gasifier equipment 3, and a booster 68 is provided in the middle of the gas turbine 7. Therefore, in the combustor 62, a part of the compressed air supplied from the compressor 61 and at least a part of the fuel gas supplied from the gas refining facility 5 are mixed and burned to generate and burn the combustion gas. The produced combustion gas is supplied to the turbine 63. Then, the turbine 63 rotationally drives the generator 19 by rotationally driving the rotary shaft 64 with the supplied combustion gas.

The steam turbine 18 includes a turbine 69 connected to a rotating shaft 64 of the gas turbine 7, and a generator 19 is connected to a base end portion of the rotating shaft 64. An exhaust gas line 70 is connected to the discharge side of the turbine 63 of the gas turbine 7. The exhaust heat recovery boiler 20 generates steam by exchanging heat between the water supply and the exhaust gas of the turbine 63. The exhaust heat recovery boiler 20 is provided with a steam supply line 71 between the exhaust heat recovery boiler 20 and the steam turbine 18. Therefore, in the steam turbine 18, the turbine 69 is rotationally driven by the steam supplied from the exhaust heat recovery boiler 20, and the generator 19 is rotationally driven by rotating the rotary shaft 64.

A chimney 75 is connected to the outlet of the exhaust heat recovery boiler 20, and the combustion gas is released to the atmosphere. A gas purification facility may be provided at the outlet of the exhaust heat recovery boiler 20.

Next, the operation of the gasification combined cycle facility 1 of the present embodiment will be described.
In the gasification composite power generation facility 1 of the present embodiment, when raw coal (coal) is supplied to the coal supply facility 9, the coal is pulverized into fine particles in the coal supply facility 9 to become pulverized coal. The pulverized coal produced in the coal supply facility 9 is supplied to the gasifier facility 3 through the nitrogen supply line 43 by the nitrogen supplied from the air separation facility 42. Further, the char recovered by the char recovery facility 11 is supplied to the gasifier facility 3 through the char transport system 45 through which the generated gas guided from the refined gas supply line 28 flows as a transport gas. Further, the compressed air extracted from the gas turbine 7 is boosted by the booster 68, and then supplied to the gasifier facility 3 through the compressed air supply line 41 together with the oxygen supplied from the air separation facility 42.

The burners 30 and 31 to which the pulverized coal and / or the char are guided burn the pulverized coal and the char with compressed air (oxygen) in the gasification furnace main body 16a, and the pulverized coal and the char are gasified to generate gas. To generate. The generated gas generated in the gasifier equipment 3 is discharged from the gasifier equipment 3 through the generated gas line 49 and sent to the char recovery equipment 11.

In the char recovery equipment 11, the generated gas is first supplied to the dust collecting equipment 51, so that the fine chars contained in the generated gas are separated. Then, the generated gas from which the char is separated is sent to the gas refining facility 5 through the gas discharge line 53. On the other hand, the fine char separated from the generated gas is deposited on the char supply hopper 52, supplied to the gasifier facility 3 through the char return line 46, and recycled.

The generated gas from which the char is separated by the char recovery facility 11 is gas refined by removing impurities such as sulfur compounds and nitrogen compounds in the gas refining facility 5, and fuel gas is produced. The fuel gas is supplied to the combustor 62 of the gas turbine 7 through the refined gas supply line 28.
In the combustor 62, the compressed air supplied from the compressor 61 and the fuel gas supplied from the gas refining facility 5 are mixed and burned to generate combustion gas. By rotationally driving the turbine 63 with this combustion gas, the compressor 61 and the generator 19 are rotationally driven via the rotating shaft 64 to generate electricity.

The exhaust heat recovery boiler 20 generates steam by exchanging heat between the exhaust gas discharged from the turbine 63 of the gas turbine 7 and the water supply, and supplies the generated steam to the steam turbine 18. In the steam turbine 18, the generator 19 is rotationally driven via the rotating shaft 64 by being rotationally driven by the steam supplied from the exhaust heat recovery boiler 20, and power is generated.
The gas turbine 7 and the steam turbine 18 do not have to be rotationally driven by one generator 19 as the same axis, and a plurality of generators may be rotationally driven as different axes.

According to this embodiment, the following effects are exhibited.
As the product gas used as the char transport medium, it was decided to use the product gas from which _{H 2 S was removed.} This makes it possible to pipes and valves of the char transport system 45 and char carrier gas supply system 48 avoids corrosion by corrosive H _{2 S.}
Since nitrogen is not required as the char transport medium, the power of the air separation equipment 42 can be reduced, and the efficiency of the plant can be expected to be improved.

Since it was decided to guide the generated gas having a temperature of 100 ° C. or higher to the char transport gas supply system 48 and to guide the generated gas having a relatively high temperature in advance, the gasification temperature was raised from the char transport gas supply system 48. The heating means for heating can be removed. Further, even when the char transport gas supply system 48 is provided with a heating means such as a heat exchanger, the capacity can be reduced.

It was decided to adjust the amount of cooling in the gas cooler 23 by the pressure control valve 27 that adjusts the pressure of the boiler water supply (BFW). Thereby, the temperature of the generated gas led to the char transport gas supply system 48 can be controlled to a desired value of 100 ° C. or higher.
Further, when a gas gas heater (GGH) is used instead of the gas cooler 23, the temperature of the generated gas cannot be controlled unless a bypass line is provided. In addition, the provision of a bypass line affects cost increase and space design. On the other hand, since the gas cooler 23 is used, the temperature can be controlled by adjusting the pressure of the boiler water supply (BFW) supplied to the gas cooler 23, and the bypass line becomes unnecessary.

In the present embodiment, the gasification complex power generation facility has been described as an example of application of the gasification furnace facility, but a plant other than the gasification complex power generation facility 1, for example, a gas for obtaining a desired chemical species from the generated gas. It may be used as a gasification furnace facility. In this case, power generation equipment such as a gas turbine is omitted.

Further, in the above-described embodiment, coal is used as the fuel, but the fuel is not limited to coal, and may be biomass used as an organic resource derived from recyclable organisms. It is also possible to use grasses, wastes, sludge, tires and recycled fuels (pellets and chips) made from these.

Further, although the tower type gasification furnace has been described as the gasification furnace in this embodiment, a crossover type gasification furnace in which the gas distribution path is folded back in a substantially inverted U shape at the upper part may be used.

1 Gasification compound power generation equipment 3 Gasification furnace equipment 5 Gas purification equipment 7 Gas turbine 11 Char recovery equipment (char separator)
13 Coal mill 14 Pulverized coal supply hopper 15 Coal supply line 16 Gasifier 16a Gasifier body 16b Pressure vessel 19 Generator 20 Exhaust heat recovery boiler 21 First heat exchanger 22 COS converter 23 Gas cooler 24 Second heat exchanger 25 cooling the washing tower 26 _{H 2} S absorption tower (corrosive gas removing means)
27 Pressure control valve (produced gas temperature adjusting means)
28 Refined gas supply line 35 Syngas cooler 36 Syngas compressor 37 Start-up nitrogen supply line 43 Nitrogen supply line 45 Char transfer system 46 Char return line 48 Char transfer gas supply system 48a Upstream end 48b Connection position

Claims (3)

The gasifier body that gasifies carbon-containing solid fuel and
A char separator that separates char from the generated gas generated in the gasifier body, and
A char transport system that transports the char separated by the char separator to the gasifier main body, and a char transport system.
A corrosive gas removing means for removing the corrosive gas from the generated gas obtained by separating the char with the char separator,
A char transport gas supply system that guides a part of the generated gas from which the corrosive gas is separated by the corrosive gas removing means to the char transport system, and a char transport gas supply system.
With
A generated gas having a temperature of 100 ° C. or higher is introduced into the char transport gas supply system.
A generated gas temperature adjusting means for adjusting the temperature of the produced gas leading to the char transport gas supply system is provided.
The generated gas temperature adjusting means is provided between the char separator and the corrosive gas removing means, and is a gas cooler that exchanges heat between the generated gas separated by the char separator and the cooling medium. Gasifier equipment featuring. The gasifier facility according to claim 1 , wherein the gas cooler is provided on the upstream side of the corrosive gas removing means in the flow direction of the generated gas. The gasifier equipment according to claim 1 or 2, and
A gas turbine driven by the generated gas derived from the gasifier facility and
A generator driven by the gas turbine and
Gasification combined cycle power generation equipment characterized by being equipped with.

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