JP5922338B2 - Fluidized bed drying equipment and gasification combined cycle power generation system using fluidized bed drying equipment - Google Patents

Description

  The present invention relates to a fluidized bed drying facility applicable to a gasification system for gasifying coal and a gasification combined power generation system using the fluidized bed drying facility.

  For example, a combined coal gasification power generation facility is a power generation facility that aims to further increase the efficiency and environmental performance compared to conventional coal-fired power generation by gasifying coal and combining it with combined cycle power generation. This coal gasification combined cycle power generation facility has a great merit that it can use coal with abundant resources, and it is known that the merit can be further increased by expanding the applicable coal types.

  Conventional coal gasification combined power generation facilities generally have a coal supply device, a drying device, a coal gasification furnace, a gas purification device, a gas turbine facility, a steam turbine facility, an exhaust heat recovery boiler, a gas purification device, and the like. ing. Therefore, the coal is dried and then pulverized, supplied to the coal gasifier as pulverized coal, and air is taken in. The coal gas is combusted and gasified in this coal gasifier, and the product gas (combustible) Gas) is produced. Then, the product gas is purified and then supplied to the gas turbine equipment to burn and generate high-temperature and high-pressure combustion gas to drive the turbine. The exhaust gas after driving the turbine recovers thermal energy by the exhaust heat recovery boiler, generates steam and supplies it to the steam turbine equipment, and drives the turbine. As a result, power generation is performed. On the other hand, the exhaust gas from which the thermal energy has been recovered is released into the atmosphere through a chimney after harmful substances are removed by the gas purification device.

By the way, the coal used in such a coal gasification combined cycle power generation system (IGCC) uses high-grade coal (high-grade coal) having a high calorific value such as bituminous coal and anthracite coal.
The coal supplied to the combined coal gasification combined power generation system (IGCC) needs to be pulverized from the viewpoint of reactivity in the coal gasification furnace and air current conveyance, and a coal mill is used as a pulverized coal machine. . For this reason, the coal supplied as a raw material is first roughly pulverized by a crusher, then dried by a dryer, and then stored by a dry coal bunker. Subsequently, it is supplied to a coal mill by a coal supply machine, where it is pulverized and dried to be pulverized coal, and then transferred from a carrier gas and supplied to a coal gasifier (Patent Document 1).

JP 7-279621 A

By the way, although the coal dried with the dryer has a fine grain and a coarse grain, conventionally both are discharged | emitted from one discharge port, and are supplied to the downstream process.
In particular, when a pulverized coal machine that pulverizes dry coal in the downstream is installed, even fine particles that do not need to be crushed are supplied, so the capacity of the pulverized coal machine becomes excessively larger than necessary. ,There's a problem.

  In addition, in recent years, in addition to high-grade coal (high-grade coal) having a high calorific value such as bituminous coal and anthracite coal, for example, low moisture having a relatively high calorific value such as subbituminous coal and lignite Although it has been proposed to gasify using low-grade coal (also referred to as “low-grade coal” or “high-moisture coal”), this low-grade coal has a high water content (for example, about 60 moisture). Therefore, the amount of water brought in is large, and the power generation efficiency decreases due to this moisture. Therefore, in the case of low-grade coal, the low-grade coal is dried by the above-mentioned drying device to remove moisture and further pulverized. When pulverized by a mill and supplied to a coal gasifier, there are problems that the number of equipment is large, the system becomes complicated, and the equipment cost increases.

  Therefore, the advent of fluidized bed drying equipment that can be supplied to a gasification system that gasifies coal with high efficiency and can reduce costs is eagerly desired.

  In view of the above problems, the present invention provides a fluidized bed drying facility that can be supplied to a gasification system with high efficiency and can reduce costs, and a gasification combined power generation system using the fluidized bed drying facility. This is the issue.

The first invention of the present invention for solving the above-mentioned problems is a fluidized bed drying device that forms a drying chamber for drying low-grade coal, and a low-grade coal that is charged into one end of the fluidized bed drying device. Grade coal input line, fluidized gas supply line that forms a fluidized bed with low grade coal by supplying fluidized gas to the lower part of the drying vessel, fluidized gas and generated steam from above the fluidized bed dryer A gas discharge line for discharging the gas, a heating unit for heating the low-grade coal supplied into the fluidized bed, and fine dry coal heated and dried from the vicinity of the upper part of the fluidized bed on the side different from the low-grade coal charging line. A fine dry coal discharge line for discharging, and a coarse dry coal discharge line for discharging coarse dry coal heated and dried from the vicinity of the bottom of the fluidized bed on the side different from the low-grade coal input line, To fluidized bed drying equipment That.

  A second invention is a fluidized bed drying according to the first invention, further comprising a coarse dry coal circulation line for supplying separated coarse dry coal into the drying vessel from the vicinity of the low-grade coal input line. In the facilities.

  3rd invention is the coal gasification furnace which processes the 1st or 2 fluidized-bed drying equipment, and the fine dry coal dried from the low grade coal supplied from the said fluidized-bed drying equipment, and converts it into gasification gas A gas turbine (GT) operated by using the gasified gas as fuel, a steam turbine (ST) operated by steam generated by an exhaust heat recovery boiler for introducing turbine exhaust gas from the gas turbine, and the gas A gasification combined power generation system using coal comprising a turbine and / or a generator (G) connected to the steam turbine.

  According to the fluidized bed drying equipment of the present invention, it is possible to gasify by drying low-grade coal without using a conventional pulverized pulverized coal machine, and separate fine particles and coarse particles. And equipment and utility costs can be significantly reduced.

FIG. 1 is a schematic diagram of a fluidized bed drying facility according to the first embodiment. FIG. 2 is a schematic diagram of a fluidized bed drying facility according to the second embodiment. FIG. 3 is a schematic configuration diagram of a gasification combined power generation system using coal according to the third embodiment. FIG. 4 is a diagram showing the relationship with the HGI index for various coals. FIG. 5 is a diagram showing an example of the particle size distribution of dry coal.

  Exemplary embodiments of fluidized bed drying equipment according to the present invention will be described below in detail with reference to the accompanying drawings. In addition, this invention is not limited by this Example, Moreover, when there exists multiple Example, what comprises combining each Example is also included.

FIG. 1 is a schematic diagram of a fluidized bed drying facility according to the first embodiment.
As shown in FIG. 1, a fluidized bed drying apparatus 100A according to this embodiment includes a pulverizer 23 for pulverizing low-grade coal (coal) 101, and a drying chamber for drying pulverized coal 101A pulverized by the pulverizer 23. A fluidized bed drying apparatus 102, a low-grade coal charging line 120 for charging crushed coal 101A to one end of the fluidized bed drying apparatus 102, and a fluidized steam that is a fluidized gas at the bottom of the fluidized bed drying apparatus 102. A fluidized gas supply line 121 that forms a fluidized bed 111 together with low-quality coal by supplying 107, a gas discharge line 122 that discharges fluidized gas and generated steam from above the fluidized bed drying apparatus 102, and the flow The heat transfer member 103, which is a heating unit that heats the pulverized coal 101A supplied in the bed 111, and the vicinity of the upper part of the fluidized bed 111 on the side different from the coal supply line 120 are added. A fine dry coal discharge line 123 for discharging the dried particulate of dry coal 101B _{F (FINE),} the coal injection lines 120 and different side of dry coal 101B from the vicinity of the bottom of the heat dried coarse fluidized bed 111 _{R (ROUGH ) And} a coarse dry charcoal discharge line 124. The gas discharge line 122 includes a dust collector 105 such as a cyclone that removes dust in the generated steam 104, and a heat recovery unit that is disposed downstream of the dust collector 105 and recovers the heat of the generated steam 104. The system 106 and the cooler 31 that cools the dry coal 101B extracted from the fluidized bed drying apparatus 102 are provided.
Reference numeral 116 denotes a rectifying plate that rectifies the fluidized steam 107 that is a fluidized gas.

  In the fluidized bed drying facility 100A, the coal 101 is supplied to the pulverizer 23 by a supply hopper (not shown) and pulverized into the pulverized coal 101A. The pulverized coal 101 </ b> A is introduced into the fluidized bed drying apparatus 102 from an inlet (not shown) and is fluidized by the fluidized steam 107 separately introduced into the fluidized bed drying apparatus 102 to form a fluidized bed 111.

  The heat transfer member 103 is disposed in the fluidized bed 111. For example, 150 ° C. drying steam (superheated steam) A is supplied into the heat transfer member 103, and the pulverized coal 101A is indirectly dried using the latent heat of the high-temperature drying steam (superheated steam) A. I am doing so. The drying steam (superheated steam) A used for drying is discharged to the outside of the fluidized bed drying apparatus 102 as, for example, 150 ° C. condensed water B.

  That is, since the drying steam (superheated steam) A condenses on the inner surface of the heat transfer member 103, which is a heating means, and becomes liquid (moisture), the condensation latent heat radiated at this time is used to heat the crushed coal 101A for drying It is used effectively. In addition to the high-temperature drying steam (superheated steam) A, any heating medium that accompanies phase change may be used, and examples thereof include Freon, pentane, and ammonia. In addition to using a heat medium as the heat transfer member 103, an electric heater may be installed.

The generated steam 104 generated when the pulverized coal 101 </ b> A is dried by the heat transfer member 103 flows in the fluidized bed drying apparatus 102 from the free board portion F formed in the upper space of the fluidized bed 111 through the gas discharge line 122. It is discharged outside the layer drying apparatus 102. Since the generated steam 104 includes a material obtained by drying and pulverizing the coal 101, the generated steam 104 is collected by, for example, a dust collector 105 and separated as a solid component 115.
The solid component 115 is merged into fine dry coal discharge line 123 for discharging the dried coal 101B _F of fine withdrawn from the fluidized bed dryer 102, it is mixed with dry coal 101B _F of fine, cooled by the cooler 110 And then supplied to the coal gasifier 14.

  On the other hand, since the generated steam 104 after being collected by the dust collector 105 is, for example, steam at 105 to 110 ° C., it is recovered by the heat recovery system 106, processed by the water treatment unit 112, and drained 113. Is discharged to the outside of the fluidized bed drying facility 100A. Note that the generated steam 104 after being collected by the dust collector 105 may be applied to, for example, a heat exchanger, a steam turbine, or the like to effectively use the heat.

  Further, a part of the generated steam 104 after being collected by the dust collector 105 is sent into the fluidized bed drying device 102 by, for example, the circulation fan 114 interposed in the fluidized gas supply line 121 and is pulverized coal. It is used as fluidized steam 107 for fluidizing the fluidized bed 111 of 101A. As a fluidizing medium for fluidizing the fluidized bed 111, a part of the generated steam 104 is reused. However, the fluidizing medium is not limited to this. For example, nitrogen, carbon dioxide, or a low oxygen concentration containing these gases is used. Air may be used.

The fluidized bed drying apparatus 102 described above exemplifies a tube-shaped heat transfer member as the heat transfer member 103, but the present invention is not limited to this, for example, a plate-shaped heat transfer member May be used.
Moreover, although the structure which supplies the steam (superheated steam) A for drying to the heat-transfer member 103 and dries the ground coal 101A indirectly was demonstrated, it is not restricted to this, The flow which flows the fluidized bed 111 of the ground coal 101A A configuration in which the pulverized coal 101A is directly dried by the activated steam 107, and a configuration in which a fluidizing gas for heating is supplied and dried may be employed.

In this embodiment, by utilizing the property of the distribution of deviation of fine and coarse particles and which is formed in the fluidized bed 111, a fine dry coal discharge line 123 for discharging the dried coal 101B _F of fine, dry coarse a coarse dry coal discharge line 124 for discharging the charcoal 101B _R, by providing on the layer upper the layer bottom of the fluidized bed 111, can be discharged separately and coarse particles and fine particles.
Thereby, the dispersion | variation in the particle size supplied to the coal gasification furnace 14 can be suppressed.
Even when a pulverized coal machine is installed on the downstream side, the equipment capacity of the downstream process can be reduced by supplying only coarse particles.

  In the present invention, the type of coal is not particularly limited, and high-grade coal (high-grade coal) having a high calorific value such as bituminous coal or anthracite coal, such as sub-bituminous coal or lignite, has a high water content. Any (for example 50-60%) low grade coal (low grade coal or high moisture coal) can be applied.

  In addition, when applying high-grade coal (high-grade coal) having a high calorific value such as bituminous coal or anthracite to a spouted bed gasifier, it is essential to install a pulverizer. In the case of low grade coal (low grade coal or high moisture coal) with a high water content (for example, 50-60%) such as bituminous coal and lignite, it is dried without being pulverized using a pulverized coal machine. Since the coal 101B can be supplied to the coal gasification furnace 14 as it is, the equipment of the pulverizer and its utility cost can be reduced.

  This is a low-grade coal (low grade coal or high moisture coal) having a high water content (for example, 50 to 60%) such as subbituminous coal or lignite used in the present invention, which is an indicator of coal pulverization. This is because the grindability is good because the HGI (HardGroveIndex) index is high.

  Here, HGI means that a certain amount of coal is pulverized for a predetermined time and a weight ratio equal to or less than a predetermined particle size is used as the index. For this reason, the larger the number, the easier it is to pulverize. Normally, the HGI index is around 50, the HGI index of 40 or less is considered to be hard, and conversely, the HGI index of 60 or more is determined to be brittle.

FIG. 4 is a diagram showing the relationship with the HGI index for various coals.
From FIG. 4, it can be seen that lignite, which is a low-grade coal, has a high HGI index of 80 or more and is softer than bituminous coal, which is a high-grade coal.
As a result, the coarse particles can be atomized by friction and collision in the fluidized bed 111, and the ratio of the atomization rate is improved.

FIG. 5 is a diagram showing an example of the particle size distribution of dry coal.
The distribution in FIG. 5 is a relationship diagram between the weight ratio on the sieve and the mesh (μm) when the brown coal A in FIG. 4 is dried with a fluidized bed drying apparatus 102 using a pulverized product of 5 mm or less.
As shown in FIG. 5, when dried with the fluidized bed drying apparatus 102, it was found that the particle size distribution had a width having a peak around 1000 μm.

The particle size of the pulverized coal 101A depends on the degree of pulverization of the pulverizer 23. For example, the particle size of the pulverized coal 101A is 10 mm or less, preferably 5 mm or less. Good and preferable.
Here, the target particle size range for pulverization by the pulverizer 23 is about 2 mm or less, but the present invention is not limited to this.

  The degree of drying in the fluidized bed drying apparatus 102 varies depending on the water content of the supplied pulverized coal 101A, but the degree of drying is preferably 15% or less, more preferably 10% or less. This is because energy loss in the coal gasification furnace is reduced when the dry state is good.

  4 and 5, lignite, which is a low-grade coal, has a high moisture content, but is softer than a high-grade coal. And since it is fluidized while moisture is removed by drying in the fluidized bed drying apparatus 102, the ratio of the mesh diameter is 2000 μm or less, and the dried coal 101B having characteristics that are easily gasified in a coal gasification furnace Become.

  Therefore, when using low-grade coal as coal, pulverization processing by a pulverizer such as high-grade coal can be omitted at all. Thereby, installation of a pulverized coal machine becomes unnecessary, and the equipment supplied to the gasification combined power generation system can be made compact.

  Moreover, it is preferable that the superficial velocity in the coal gasification furnace 14 is a superficial velocity at which the dried and cooled cooled dry coal 101B supplied directly into the furnace does not fall. Thereby, favorable gasification of dry charcoal 101B is attained.

FIG. 2 is a schematic diagram of a fluidized bed drying facility according to the second embodiment.
As shown in FIG. 2, the fluidized bed drying equipment 100B according to this embodiment, in a fluidized bed drying equipment 100A according to the first embodiment, the dry coal 101B _R of coarse particles through a coarse dry coal circulation line 125, It is supplied to the vicinity of the inlet of the coal input line 120, thereby introducing dry coal 101B _R coarse grains fluidized bed dryer 102 again. Thereby, atomization of coarse particles due to friction and collision in the fluidized bed 111 can be achieved, and the ratio of the atomization rate can be improved.
Further, since supplying dry coal 101B _R of the dried coarse particles, it is possible to prevent the flow failure of ground coal 101A wetting material, it is possible to improve the drying efficiency.

  FIG. 3 is a schematic configuration diagram of a gasification combined power generation system using coal according to the third embodiment.

  The integrated gasification combined power generation system (IGCC: Integrated Coal Gasification Combined Cycle) using coal of Example 3 adopts an air combustion system that generates coal gas in a coal gasification furnace using air as an oxidizer, and is a gas purification device. The refined coal gas is supplied as fuel gas to the gas turbine equipment for power generation. That is, the combined coal gasification combined power generation facility of this embodiment is a power generation facility of an air combustion system (air blowing). In this embodiment, low-grade coal is used as a coal raw material supplied to the coal gasifier 14.

  In Example 3, as shown in FIG. 3, the coal gasification combined power generation facility 10 includes a low-grade coal supply facility 11 that supplies coal 101 that is raw coal, a fluidized bed drying device 102 that dries the coal 101, A coal gasification furnace 14 that supplies dry low-grade coal (dry coal) 101B to gasify and generates a combustible gas (product gas, coal gas) 200, and a combustible gas (product gas, coal gas) that is a gasification gas ) Char recovery device 15 that recovers char 101C in 200, gas purification device 16 that purifies combustible gas (product gas, coal gas) 200A, and gas that drives the turbine by burning purified fuel gas 200B Turbine facility 17 and a heat recovery steam generator (H) that introduces turbine exhaust gas from gas turbine facility 17 A steam turbine (ST) facility 18, which is operated by the steam generated by the SG) 20, which comprises a said gas turbine equipment 17 and / or the steam turbine plant 18 and linked generator (G) 19.

  The low-grade coal supply facility 11 according to the present embodiment includes a raw coal bunker 21, a coal supply machine 22, and a pulverizer 23. The raw coal bunker 21 can store the coal 101, and can drop a predetermined amount of the coal 101 into the coal feeder 22. The coal feeder 22 can transport the coal 101 dropped from the raw coal bunker 21 by, for example, a conveyor and drop it on the crusher 23. The pulverizer 23 can pulverize the dropped coal 101 into a predetermined size to obtain pulverized coal 101A.

  The fluidized bed drying apparatus 102 supplies drying steam (for example, superheated steam at about 150 ° C.) A to the coal 101 input by the low-grade coal supply facility 11, thereby heating the low-grade coal while flowing. It is what is dried, and the moisture contained in the coal 101 can be removed. The fluidized bed drying apparatus 102 is provided with a cooler 31 for cooling the dried dry coal 101B taken out to the outside, and the dried and cooled dry coal 101B is stored in the dry coal bunker 34. In addition, the fluidized bed drying apparatus 102 is provided with a dust collector 105 such as a dry coal cyclone that separates dry coal particles accompanying the generated steam 104 taken out from the upper portion. The particles are separated. Note that the steam from which the dry coal is separated by the dust collector 105 such as a cyclone may be supplied to the fluidized bed drying apparatus 102 as drying steam after being compressed by a steam compressor.

Dry and cooled dry charcoal 101B dried by the fluidized bed drying apparatus 102 and then cooled by the cooler 31 is discharged as fine dry charcoal 101B _{F (FINE)} heated and dried from the vicinity of the upper part of the fluidized bed 111, and is finely granulated. It is stored in the temporary dry coal bunker 34 via the dry coal discharge line 123 and then via the bag filter 32 and the bin system 33.
On the other hand, coarse dry coal 101BR _(ROUGH) heated and dried from the vicinity of the bottom of the fluidized bed 111 on the side different from the coal input line 120 is separately installed through a coarse dry coal discharge line 124. It is also possible to supply heat to the heat source and burn it here for heat recovery.

  In addition, as shown in the second embodiment, the fluidized bed drying device 102 may be returned to the inlet.

Coal gasification furnace 14, along with the dry coal 101B _F of fine supplied from dry coal bunker 34 can be supplied, 101C (unburned coal) recovered char in the char recovery equipment 15 is returned to recycle It is possible.

That is, the coal gasification furnace 14 is connected to the compressed air supply line 41 from the gas turbine equipment 17 (compressor 61), and can supply compressed air compressed by the gas turbine equipment 17. The air separation device 42 separates and generates nitrogen (N ₂ ) and oxygen (O ₂ ) from air 40 in the atmosphere. A first nitrogen supply line 43 is connected to the coal gasifier 14, and the first The nitrogen supply line 43 is connected to the dry coal supply line 123. The second nitrogen supply line 45 is also connected to the coal gasification furnace 14, and a char return line 46 for returning the char 101 C recovered from the char recovery device 15 is connected to the second nitrogen supply line 45. Further, the oxygen supply line 47 is connected to the compressed air supply line 41. In this case, nitrogen (N ₂ ) is used as a transport gas for dry charcoal 101B and char 101C, and oxygen (O ₂ ) is used as an oxidizing agent.

The coal gasification furnace 14 is, for example, a spouted bed type gasification furnace that combusts fine dry coal 101B _F , char 101C, air (oxygen) supplied therein, or steam as a gasifying agent. While being gasified, a combustible gas (generated gas, coal gas) 200 containing carbon monoxide as a main component is generated, and a gasification reaction is generated using the combustible gas 200 as a gasifying agent. The coal gasification furnace 14 is provided with a foreign matter removing device 48 for removing foreign matters such as molten slag mixed with pulverized coal.
In this example, a spouted bed gasification furnace is illustrated as the coal gasification furnace 14, but the present invention is not limited to this, and may be, for example, a fluidized bed gasification furnace or a fixed bed gasification furnace. The coal gasification furnace 14 is provided with a gas generation line 49 of the combustible gas 200 toward the char recovery device 15, and the combustible gas 200 including the char 101C can be discharged. In this case, a gas cooler is separately provided in the gas generation line 49 so that the combustible gas 200 is cooled to a predetermined temperature and then supplied to the char recovery device 15.

  The char recovery device 15 includes a dust collector 51 and a char supply hopper 52. In this case, the dust collector 51 is constituted by one or a plurality of bag filters or cyclones, and can separate the char 101C contained in the combustible gas 200 generated in the coal gasification furnace 14. The combustible gas 200 </ b> A from which the char 101 </ b> C has been separated is sent to the gas purification device 16 through the gas discharge line 53. The char supply hopper 52 stores the char 101 </ b> C separated from the combustible gas 200 by the dust collector 51. A bin may be disposed between the dust collector 51 and the supply hopper 52, and a plurality of char supply hoppers 52 may be connected to the bin. A char return line 46 from the supply hopper 52 is connected to the second nitrogen supply line 45.

The gas purification device 16 performs gas purification by removing impurities such as sulfur compounds and nitrogen compounds from the combustible gas 200A from which the char 101C has been separated by the char recovery device 15. Then, the gas purifier 16 purifies the combustible gas 200A from which the char 101C is separated to produce the fuel gas 200B, and supplies this to the gas turbine equipment 17. In this gas purification device 16, since the combustible gas 200A from which the char 101C has been separated still contains a sulfur content (H ₂ S), the sulfur content is removed by, for example, an amine absorbing solution. Is finally collected as gypsum and used effectively.

  The gas turbine equipment 17 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. The combustor 62 has a compressed air supply line 65 connected to the compressor 61, a fuel gas supply line 66 connected to the gas purifier 16, and a combustion gas supply line 67 connected to the turbine 63. Further, the gas turbine equipment 17 is provided with a compressed air supply line 41 extending from the compressor 61 to the coal gasification furnace 14, and a booster 68 is provided in the middle. Therefore, in the combustor 62, the compressed air 40 </ b> A supplied from the compressor 61 and the fuel gas 200 </ b> B supplied from the gas purification device 16 are mixed and burned, and the rotating shaft is generated by the generated combustion gas 202 in the turbine 63. The generator 19 can be driven by rotating 64.

  The steam turbine facility 18 includes a turbine 69 that is coupled to the rotating shaft 64 in the gas turbine facility 17, and the generator 19 is coupled to the base end portion of the rotating shaft 64. The exhaust heat recovery boiler 20 is provided in the exhaust gas line 70 from the gas turbine equipment 17 (the turbine 63), and generates steam 204 by exchanging heat between the air 40 and the high temperature exhaust gas 203. It is. Therefore, the exhaust heat recovery boiler 20 is provided with a steam supply line 71 for supplying the steam 204 to and from the turbine 69 of the steam turbine equipment 18, a steam recovery line 72 is provided, and the steam recovery line 72 has a condenser. 73 is provided. Therefore, in the steam turbine equipment 18, the turbine 69 is driven by the steam 204 supplied from the exhaust heat recovery boiler 20, and the generator 19 can be driven by rotating the rotating shaft 64.

  The exhaust gas 205 whose heat has been recovered by the exhaust heat recovery boiler 20 is freed of harmful substances by the gas purification device 74, and the purified exhaust gas 205A is released from the chimney 75 to the atmosphere.

  Here, the action | operation of the coal gasification combined cycle power generation equipment 10 of Example 3 is demonstrated.

In the combined coal gasification combined power generation facility 10 of the third embodiment, the raw coal 101 is stored in the raw coal bunker 21 in the low-grade coal supply facility 11, and the coal 101 of the raw coal bunker 21 is supplied as coal. The machine 22 drops the pulverizer 23 where it is crushed to a predetermined size. Then, crushed pulverized coal 101A is heated and dried by fluidized bed dryer 102, dried by separated into a dry coal 101B _R of dry coal 101B _F and coarse grains fine, fine only dry coal 101B _F of fine after extracting through a dry coal discharge line 123, is cooled by the cooler 31 is a dry coal 101B _F of chilled of fine, it is stored in the dry coal bunker 34.

Dry coal 101B _F of stored in dry coal bunker 34 fine is provided by the nitrogen supplied from the air separation unit 42 through fine dry coal discharge line 123 to the coal gasification furnace 14. Further, the char 101C recovered by the char recovery device 15 to be described later is supplied to the coal gasification furnace 14 through the char return line 46 by nitrogen supplied from the air separation device 42. Further, compressed air 37 extracted from a gas turbine facility 17 to be described later is pressurized by a booster 68 and then supplied to the coal gasifier 14 through the compressed air supply line 41 together with oxygen supplied from the air separation device 42. .

In the coal gasification furnace 14, by dry coal 101B _F and char 101C of the supplied fine combusts by compressed air (oxygen) 37, dry coal 101B _F and char 101C of fine is gasified, carbon monoxide A combustible gas (coal gas) 200 as a main component can be generated. The combustible gas 200 is discharged from the coal gasifier 14 through the gas generation line 49 and sent to the char recovery device 15.

  In the char recovery device 15, the combustible gas 200 is first supplied to the dust collector 51, whereby the char 101 </ b> C contained in the combustible gas 200 is separated here. The combustible gas 200 </ b> A from which the char 101 </ b> C has been separated is sent to the gas purification device 16 through the gas discharge line 53. On the other hand, the fine char 101C separated from the combustible gas 200 is deposited on the char supply hopper 52, returned to the coal gasifier 14 through the char return line 46, and recycled.

  The combustible gas 200A from which the char 101C has been separated by the char recovery device 15 is gas purified by removing impurities such as sulfur compounds and nitrogen compounds in the gas purification device 16 to produce a fuel gas 200B. In the gas turbine equipment 17, when the compressor 61 generates the compressed air 40 </ b> A and supplies it to the combustor 62, the combustor 62 is supplied from the compressed air 40 </ b> A supplied from the compressor 61 and the gas purification device 16. The fuel gas 200B is mixed and burned to generate a combustion gas 202. By driving the turbine 63 with the combustion gas 202, the generator 19 is driven via the rotating shaft 64 to generate power. be able to.

  The exhaust gas 203 discharged from the turbine 63 in the gas turbine equipment 17 generates heat 204 by exchanging heat with the air 40 in the exhaust heat recovery boiler 20, and the generated steam 204 is used as the steam turbine equipment 18. To supply. In the steam turbine facility 18, the turbine 69 is driven by the steam 204 supplied from the exhaust heat recovery boiler 20, whereby the generator 19 can be driven via the rotating shaft 64 to generate power.

  Thereafter, in the gas purification device 74, harmful substances in the exhaust gas 205 discharged from the exhaust heat recovery boiler 20 are removed, and the purified exhaust gas 205A is released from the chimney 75 to the atmosphere.

  In this example, low-grade coal was used as a coal raw material, but even high-grade coal can be applied, and is not limited to coal, and can be used as a renewable bio-derived organic resource. Biomass may be used, and for example, thinned wood, waste wood, driftwood, grass, waste, sludge, tires, and recycled fuel (pellets and chips) using these as raw materials can be used.

DESCRIPTION OF SYMBOLS 10 Coal gasification combined cycle power generation equipment 11 Low-grade coal supply equipment 14 Coal gasification furnace 15 Char recovery equipment 16 Gas refinement equipment 17 Gas turbine equipment 18 Steam turbine equipment 19 Generator 20 Waste heat recovery boilers 100A, 100B Fluidized bed drying equipment 101 Low grade coal 101A Ground low grade coal (crushed coal)
101B Dry low-grade coal (dry coal)
102 Fluidized bed dryer 103 Heat transfer member (heating means)
104 Generated steam 31 Cooler A Drying steam (superheated steam)
B Condensate

Claims (3)

A fluidized bed drying device that forms a drying chamber for drying low-grade coal;
A low-grade coal input line for introducing low-grade coal to one end of the fluidized bed drying device;
A fluidized gas supply line that forms a fluidized bed with low-grade coal by supplying fluidized gas to the lower part of the drying vessel;
A gas discharge line for discharging fluidized gas and generated steam from above the fluidized bed drying device;
A heating section for heating the low-grade coal supplied in the fluidized bed;
A fine dry coal discharge line for discharging fine dry coal heated and dried from the vicinity of the upper part of the fluidized bed on the side different from the low-grade coal input line,
A fluidized bed drying facility comprising: a coarse dry coal discharge line for discharging coarse dry coal heated and dried from the vicinity of the bottom of the fluidized bed on the side different from the low-grade coal charging line. In claim 1,
A fluidized bed drying facility comprising a coarse dry coal circulation line for supplying separated coarse dry coal into the drying vessel from the vicinity of the low-grade coal charging line. Fluidized bed drying equipment according to claim 1 or 2,
A coal gasification furnace for treating fine dry coal obtained by drying low-grade coal supplied from the fluidized bed drying facility and converting it into gasification gas;
A gas turbine (GT) operated using the gasified gas as fuel;
A steam turbine (ST) operated by steam generated by an exhaust heat recovery boiler for introducing turbine exhaust gas from the gas turbine;
A gasification combined power generation system using coal, comprising the generator (G) connected to the gas turbine and / or the steam turbine.

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