JP2013167380A - Fluidized bed drying device and gasification complex power generation system using coal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fluidized bed drying device capable of improving efficiency of drying.SOLUTION: At least two or more (two in this embodiment) drying chambers 111A are formed by dividing a drying container 101 in the moving direction of the wet fuel of a fluid bed, two or more heat transfer tubes 106a for heating the wet fuel of the fluid bed are arranged in the respective drying chambers, the heat transfer tubes 106a arranged in the respective drying chambers are inserted from a direction orthogonal to the progressing direction of a dried matter, and fins 130 are arranged at the heat transfer tubes 106a at prescribed intervals in the vertical direction.

Description

  The present invention relates to a fluidized bed drying apparatus for drying a material to be dried by fluidizing steam or fluidizing gas, and a gasification combined power generation system using coal.

  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 power generation facility is not only a high-grade coal (high-grade coal) having a high calorific value such as bituminous coal and anthracite, but also a comparison such as sub-bituminous coal and lignite. There is a low-grade coal (low-grade coal) with a low calorific value. This low-grade coal has a large amount of moisture to be brought in, and the power generation efficiency decreases due to this moisture. For this reason, in the case of low-grade coal, it is necessary to dry the coal with the above-described drying apparatus to remove moisture and then pulverize and supply the coal gasifier.

  As a drying apparatus for drying such coal, there are those described in Patent Documents 1 and 2 below. The fluidized drying method and fluidized bed drying apparatus described in Patent Document 1 supplies wet fuel containing moisture from a fuel supply port to a supply chamber, and is covered by fluidized gas through a dispersion plate in the supply chamber and the drying classification chamber. When the fluid is flowed and dried and classified into fine powder and coarse particles, the layer thickness of the fluidized bed in the supply chamber is controlled separately from the layer thickness of the fluidized bed in the dry classification chamber.

  In addition, the fluidized dryer and the drying method described in Patent Document 2 are configured so that the flow rate of the heat source / fluidizing gas blown from the lower side of the gas dispersion plate just below the charging chute is below the gas dispersion plate other than the lower portion of the charging chute. It is made faster than the flow rate of the heat source and fluidizing gas blown from the side.

JP 2008-128524 A JP 2011-69609 A

  As described above, the low-grade coal has a higher moisture content than the high-grade coal, so that fluidization failure occurs in the drying device, which may cause drying failure. In particular, in the region close to the inlet portion, the water concentration is high and the dispersibility of the particles is not good. This may cause fluidization failure, adhesion, and accumulation near the heat transfer tube and at the bottom surface, resulting in blockage. . Therefore, it is necessary to reduce the amount of coal to be input, and there is a problem that the processing amount decreases.

  In the proposal described in Patent Document 1 described above, the raw material particles (raw coal) having a high water content are controlled by controlling the layer thickness of the fluidized bed in the supply chamber separately from the layer thickness of the fluidized bed in the dry classification chamber. Is stably dried and classified while suppressing the occurrence of agglomeration and adhesion to the apparatus. However, this technique has a problem that the moisture evaporation load per unit volume of the fluidized bed in the supply chamber is increased, and the amount of heat for properly drying the raw material is insufficient.

Further, in the proposal described in Patent Document 2, the flow rate of the heat source / fluidizing gas is set to be higher than the flow rate of the heat source / fluidizing gas blown from the lower side of the gas dispersion plate other than just below the charging chute. However, for example, low-grade coal such as lignite has a moisture content of 60% or more, which is higher than the moisture content of coal, which is high-grade coal (9-13%), so it is not sufficient to make the fluidizing gas faster. Therefore, further measures to cope with the drying of low-grade coal are eagerly desired.
Further, when water vapor is used for drying low-grade coal, the water vapor is condensed on the raw material particles immediately after the addition, forming aggregated particles, which may cause flow failure.
Furthermore, in some large-capacity drying devices, heat transfer tubes are provided to promote drying. However, when raw materials with extremely high water content are supplied, they adhere to the periphery of the heat transfer tubes and become blocked. There is a risk of letting it.

  This invention solves the subject mentioned above, and it aims at providing the gasification combined cycle power generation system using the fluidized-bed drying apparatus and coal which can improve a drying efficiency.

  The first invention of the present invention for solving the above-described problems includes a dry container having a hollow shape, a wet fuel input part for supplying wet fuel to one end side of the dry container, and the other end side of the dry container A dry matter discharge unit that discharges dry matter obtained by heating and drying the wet fuel, and fluidized steam or fluidization that forms a fluidized bed together with the wet fuel by supplying fluidized steam or fluidized gas to the lower part of the drying container. A gas supply unit, a gas discharge unit for discharging fluidized steam or fluidized gas and generated steam from above the drying container, and a drying container divided in the moving direction of the wet fuel in the fluidized bed; A drying chamber is formed, and each of the drying chambers is provided with a heat transfer tube that heats the wet fuel in the fluidized bed, and the heat transfer tube disposed in each of the drying chambers is perpendicular to the traveling direction of the dried product. Inserted into the heat transfer tube In fluidized bed drying apparatus characterized by comprising installing the fin in the vertical axis direction with a constant interval.

  A second invention is a fluidized bed drying apparatus according to the first invention, a coal gasification furnace that processes dry coal supplied from the fluidized bed drying apparatus and converts it into gasified gas, and fuels the gasified gas. A gas turbine (GT) operated as a steam turbine (ST) operated by steam generated by a heat recovery steam generator that introduces turbine exhaust gas from the gas turbine, the gas turbine and / or the steam turbine, A combined gasification combined power generation system using coal, characterized in that it includes a generator (G) connected thereto.

  ADVANTAGE OF THE INVENTION According to this invention, the increase effect of a heat transfer area can be exhibited by attaching a fin to the heat exchanger tube installed in the layer of a fluidized bed. At the same time, it is possible to improve the plug flow (extrusion flow) property by the partition effect by the plurality of fins.

FIG. 1 is a schematic side view showing a fluidized bed drying apparatus according to an embodiment of the present invention. FIG. 2 is a schematic cross-sectional view taken along the line AA of FIG. 1 showing the fluidized bed drying apparatus of the example. FIG. 3 is a perspective view of a part of the heat transfer tubes of the fluidized bed drying apparatus of the example. FIG. 4 is a schematic configuration diagram of a coal gasification combined power generation facility to which the fluidized bed drying apparatus of the embodiment is applied.

  Hereinafter, the present invention will be described in detail with reference to the 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. In addition, constituent elements in the following embodiments include those that can be easily assumed by those skilled in the art or those that are substantially the same.

  FIG. 1 is a schematic side view showing a fluidized bed drying apparatus according to an embodiment of the present invention, and FIG. 4 is a schematic configuration diagram of a coal gasification combined power generation facility to which the fluidized bed drying apparatus of the embodiment is applied.

  The coal gasification combined power generation facility (IGCC: Integrated Coal Gasification Combined Cycle) of the embodiment employs an air combustion method in which coal gas is generated in a gasification furnace using air as an oxidizer, and the coal after being refined by a gas purifier Electric power is generated by supplying gas as fuel gas to gas turbine equipment. 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 case, low-grade coal is used as the wet fuel supplied to the gasifier.

  In the embodiment, as shown in FIG. 4, the coal gasification combined power generation facility 10 includes a coal supply device 11, a fluidized bed drying device 12, a pulverized coal machine (mill) 13, a coal gasification furnace 14, a char recovery device 15, It has a gas purification device 16, a gas turbine facility 17, a steam turbine facility 18, a generator 19, and a heat recovery steam generator (HRSG) 20.

  The coal feeder 11 includes a raw coal bunker 21, a coal feeder 22, and a crusher 23. The raw coal bunker 21 can store low-grade coal, and can drop a predetermined amount of low-grade coal into the coal feeder 22. The coal feeder 22 can transport the low-grade coal dropped from the raw coal bunker 21 by a conveyor or the like and drop it on the crusher 23. The crusher 23 can crush the dropped low-grade coal into a predetermined size.

  The fluidized bed drying device 12 supplies drying steam (superheated steam) to the low-grade coal introduced by the coal feeder 11 so as to heat and dry the low-grade coal while flowing. Moisture contained in the graded coal can be removed. The fluidized bed drying device 12 is provided with a cooler 31 for cooling the dried low-grade coal taken out from the lower portion, and the dried and cooled dried coal is stored in the dried coal bunker 32. Further, the fluidized bed drying apparatus 12 is provided with a dry coal cyclone 33 and a dry coal electrostatic precipitator 34 for separating dry coal particles from steam taken out from above, and the dry coal particles separated from the steam are dried coal bunker. 32 is stored. The steam from which the dry coal has been separated by the dry coal electrostatic precipitator 34 is compressed by the steam compressor 35 and then supplied to the fluidized bed drying device 12 as drying steam.

  The pulverized coal machine 13 is a pulverizer, and pulverizes the low-grade coal (dried coal) dried by the fluidized bed dryer 12 into fine particles to produce pulverized coal. That is, in the pulverized coal machine 13, the dry coal stored in the dry coal bunker 32 is dropped by the coal feeder 36, and the dry coal is converted into low-grade coal having a predetermined particle size or less, that is, pulverized coal. The pulverized coal after being pulverized by the pulverized coal machine 13 is separated from the conveying gas by the pulverized coal bag filters 37a and 37b and stored in the pulverized coal supply hoppers 38a and 38b.

  The coal gasification furnace 14 can supply pulverized coal processed by the pulverized coal machine 13 and can be recycled by returning the char (unburned coal) recovered by the char recovery device 15. .

  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 and oxygen from air in the atmosphere. A first nitrogen supply line 43 is connected to the coal gasifier 14, and a pulverized coal supply hopper is connected to the first nitrogen supply line 43. Charging lines 44a and 44b from 38a and 38b are connected. The second nitrogen supply line 45 is also connected to the coal gasification furnace 14, and the char return line 46 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 is used as a carrier gas for coal and char, and oxygen is used as an oxidant.

  The coal gasification furnace 14 is, for example, a spouted bed type gasification furnace, which combusts and gasifies coal, char, air (oxygen) supplied therein or water vapor as a gasifying agent, and produces carbon dioxide. A combustible gas (product gas, coal gas) containing carbon as a main component is generated, and a gasification reaction takes place using this combustible gas as a gasifying agent. The coal gasification furnace 14 is provided with a foreign matter removing device 48 that removes foreign matter mixed with pulverized coal. In this case, the coal gasification furnace 14 is not limited to the spouted bed gasification furnace, and may be a fluidized bed gasification furnace or a fixed bed gasification furnace. The coal gasification furnace 14 is provided with a gas generation line 49 for combustible gas toward the char recovery device 15, and can discharge combustible gas containing char. In this case, by providing a gas cooler in the gas generation line 49, the combustible gas may be 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 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 char contained in the combustible gas generated in the coal gasification furnace 14. The combustible gas from which the char has been separated is sent to the gas purification device 16 through the gas discharge line 53. The supply hopper 52 stores the char separated from the combustible gas by the dust collector 51. A bin may be disposed between the dust collector 51 and the supply hopper 52, and a plurality of 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 from which the char has been separated by the char recovery device 15. The gas purifier 16 purifies the combustible gas to produce fuel gas and supplies it to the gas turbine equipment 17. In the gas purifier 16, since the combustible gas from which the char is separated still contains sulfur (H ₂ S), the sulfur is finally removed by removing it with the amine absorbent. Is recovered 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 supplied from the compressor 61 and the fuel gas supplied from the gas purifier 16 are mixed and burned, and the rotating shaft 64 is rotated by the generated combustion gas in the turbine 63. By doing so, the generator 19 can be driven.

  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 by exchanging heat between the air and the high temperature exhaust gas. Therefore, the exhaust heat recovery boiler 20 is provided with the steam supply line 71 between the steam turbine equipment 18 and the turbine 69 of the steam turbine equipment 18, the steam recovery line 72 is provided, and the steam recovery line 72 is provided with the condenser 73. Yes. Therefore, in the steam turbine facility 18, the turbine 69 is driven by the steam supplied from the exhaust heat recovery boiler 20, and the generator 19 can be driven by rotating the rotating shaft 64.

  The exhaust gas from which 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 is discharged from the chimney 75 to the atmosphere.

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

  In the coal gasification combined power generation facility 10 of the embodiment, raw coal (low-grade coal) is stored in the raw coal bunker 21 by the coal feeder 11, and the low-grade coal of the raw coal bunker 21 is used as a coal feeder. 22 is dropped onto a crusher 23 where it is crushed to a predetermined size. The crushed low-grade coal is heated and dried by the fluidized bed drying device 12, cooled by the cooler 31, and stored in the dry coal bunker 32. Further, the steam taken out from the upper part of the fluidized bed drying device 12 is separated into dry coal particles by the dry coal cyclone 33 and the dry coal electrostatic precipitator 34 and compressed by the steam compressor 35 before being supplied to the fluidized bed drying device 12. Returned as drying steam. On the other hand, the dry coal particles separated from the steam are stored in the dry coal bunker 32.

  The dry coal stored in the dry coal bunker 32 is fed into the pulverized coal machine 13 by the coal feeder 36, where it is pulverized into fine particles to produce pulverized coal, and through the pulverized coal bag filters 37a and 37b. And stored in the pulverized coal supply hoppers 38a and 38b. The pulverized coal stored in the pulverized coal supply hoppers 38 a and 38 b is supplied to the coal gasification furnace 14 through the first nitrogen supply line 43 by nitrogen supplied from the air separation device 42. Further, the char recovered by the char recovery device 15 described later is supplied to the coal gasifier 14 through the second nitrogen supply line 45 by nitrogen supplied from the air separation device 42. Further, the compressed air extracted from the gas turbine equipment 17 to be described later is boosted by the booster 68 and then supplied to the coal gasification furnace 14 through the compressed air supply line 41 together with oxygen supplied from the air separation device 42.

  In the coal gasification furnace 14, the supplied pulverized coal and char are combusted by compressed air (oxygen), and the pulverized coal and char are gasified to generate combustible gas (coal gas) mainly composed of carbon dioxide. Can be generated. The combustible gas 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 is first supplied to the dust collector 51, whereby the char contained in the gas is separated from the combustible gas. The combustible gas from which the char has been separated is sent to the gas purification device 16 through the gas discharge line 53. On the other hand, the fine char separated from the combustible gas is deposited on the supply hopper 52, returned to the coal gasifier 14 through the char return line 46, and recycled.

  The combustible gas from which the char has been separated by the char recovery device 15 is subjected to gas purification by removing impurities such as sulfur compounds and nitrogen compounds in the gas purification device 16 to produce fuel gas. In the gas turbine facility 17, when the compressor 61 generates compressed air and supplies the compressed air to the combustor 62, the combustor 62 is supplied from the compressed air supplied from the compressor 61 and the gas purification device 16. Combustion gas is generated by mixing with fuel gas and combusting, and the turbine 63 is driven by this combustion gas, so that the generator 19 can be driven via the rotating shaft 64 to generate power.

  The exhaust gas discharged from the turbine 63 in the gas turbine equipment 17 generates steam by exchanging heat with air in the exhaust heat recovery boiler 20, and supplies the generated steam to the steam turbine equipment 18. . In the steam turbine facility 18, the generator 69 can be driven through the rotating shaft 64 to generate electric power by driving the turbine 69 with the steam supplied from the exhaust heat recovery boiler 20.

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

  Hereinafter, the fluidized bed drying apparatus 12 in the coal gasification combined power generation facility 10 described above will be described in detail.

  As shown in FIG. 1, the fluidized bed drying apparatus 12 includes a drying container 101, a raw coal charging port (wet fuel charging unit) 102, a dry coal discharging port (dry matter discharging unit) 103, fluidized steam or fluidized flow. A fluidizing gas supply unit (not shown) for supplying a gasified gas (hereinafter referred to as “fluidizing gas”) 104 (104a, 104b), a gas discharge port (gas discharge unit) 105, and a heat transfer tube (heating unit) 106a. , 106b.

  The drying container 101 has a hollow box shape, and is formed with a raw coal charging port 102 for charging raw coal (wet fuel) on one end side, and dried by heating and drying raw coal on a lower portion on the other end side. A dry charcoal discharge port 103 for discharging the material is formed, and the raw coal is dried by an extrusion method (plug flow) inside the drying container 101. In this case, the raw coal input port 102 and the dry coal discharge port 103 are provided one by one at the end of the drying container 101, but a plurality of them may be provided. In addition, the drying container 101 is provided with a dispersion plate 108 having a plurality of openings at a predetermined distance from the bottom plate 101a in the lower portion, so that an air box 109 is partitioned. And the drying container 101 is provided with the fluidization gas supply part which supplies the fluidization gas (superheated steam) 104 above the dispersion | distribution board 108 via the wind box 109 by this bottom plate 101a side. Further, in the drying container 101, a gas discharge port 105 for discharging the fluidized gas 104 and generated steam is formed in the ceiling plate 101b on the dry coal discharge port 103 side.

  The drying container 101 is supplied with raw coal from the raw coal inlet 102 and supplied with fluidizing gas 104 from the fluidizing gas supply section through the wind box 109 and the dispersion plate 108, thereby A fluidized bed S having a predetermined thickness is formed above, and a free board portion F is formed above the fluidized bed S.

  And the drying container 101 of a present Example has the 1st drying chamber 111a provided in the upstream of the flow direction of raw coal, and the 2nd drying chamber 111b provided in the downstream of the flow direction of raw coal. A partition plate 113 that partitions the first drying chamber 111a and the second drying chamber 111b is provided on the dispersion plate 108.

  The partition plate 113 is installed from the upper surface of the dispersion plate 108, and an opening (a distribution port) 113a through which raw coal passes is formed in a part of the partition plate. The shape and size of the opening may be appropriately changed or changed depending on the wet state of the raw coal. Further, the upper end portion of the partition plate 113 is positioned so as to extend upward from the fluidized bed S, so that the flowd raw coal does not flow over the partition plate 113 to the downstream side.

  The first drying chamber 111a and the second drying chamber 111b communicate with each other above the partition plate 113. In this case, the first drying chamber 111a is a region in which the free board portion F1 and the fluidized bed S1 are formed to perform initial drying (preliminary drying) of the raw coal, and the second drying chamber 111b is the free board portion F2. And the fluidized bed S2 is formed, and this is a region where late drying (finish drying) of raw coal is performed.

  In this case, the wind box 109 is divided into wind boxes 109a and 109b corresponding to the first drying chamber 111a and the second drying chamber 111b, and a fluidizing gas supply unit is provided corresponding to the wind boxes 109a and 109b. . And the gas quantity of the fluidization gas 104a, 104a supplied in the wind box 109a, 109b can be adjusted by adjusting the opening degree of the flow regulating valve which is not illustrated.

Further, the heat transfer tube 106a installed in the first drying chamber 111a on the wet fuel charging unit 102 side and the heat transfer tube 106b installed in the second drying chamber 111b on the downstream side are divided into two parts in the drying container 101. The fins 130 are installed in the vertical axis direction with a predetermined interval between the heat transfer tubes 106a and 106b while being inserted from a direction orthogonal to the traveling direction of the dried product.
FIG. 2 is a schematic cross-sectional view taken along the line AA of FIG. 1 showing the fluidized bed drying apparatus of the example.
FIG. 3 is a perspective view of a part of the heat transfer tubes of the fluidized bed drying apparatus of the example.
As shown in FIGS. 2 and 3, in the fluidized bed drying apparatus of this embodiment, the heat transfer tubes 106a and 106b disposed in the first drying chamber 111a and the second drying chamber 111b are disposed in the traveling direction of the dried product. And a heat transfer tube inserted from a direction (container side wall 101c) orthogonal to the heat transfer tube. As shown in FIG. 3, the heat transfer tubes 106 a and 106 b arranged in the direction orthogonal to the traveling direction of the dried product have a plurality of fins 130 in the vertical axis direction (up and down direction of the heat transfer tubes) with a predetermined interval. Individually installed.

  By attaching the fins 130 to the heat transfer tubes 106a and 106b installed in the fluidized beds S1 and S2, the effect of increasing the heat transfer area can be exhibited. At the same time, it is possible to improve the plug flow (extrusion flow) property by the partition effect by the plurality of fins 130.

As a result, the drying characteristics can be enhanced by sharpening the residence time distribution of the dried product.
As described above, it is possible to improve the drying characteristics by providing a plurality of fins 130 at predetermined intervals on the heat transfer tubes 106a and 106b disposed in the first drying chamber 111a and the second drying chamber 111b.

  In this embodiment, the heat transfer tubes 106a and 106b are installed so as to intersect the traveling direction of the dried product and the direction orthogonal to the traveling direction, but only the heat transfer tube in the direction orthogonal to the traveling direction may be used. Good.

  In addition, the width (L) and height (H) of the fin 130 and the pitch (P) between the fins 130 and 130 are appropriately set according to the moving state of the dry matter. Also, the settings in the first drying chamber 111a and the second drying chamber 111b are made different, for example, the pitch (P) between the fins 130, 130 in the first drying chamber 111a is widened, and the progress is good, You may make it improve the drying characteristic by narrowing the pitch (P) in the 2nd drying chamber 111b, and exhibiting the partition effect.

  In the present embodiment, the first drying chamber 111a and the second drying chamber 111b are divided via the partition plate 113, but the present invention is not limited to this, and the drying container can be provided without providing the partition plate 113. 101 may be divided. This is because the drying chamber 101 can be apparently divided without providing a partition plate when the drying chamber is long in the flow direction.

  Here, the whole operation | movement of the fluidized-bed drying apparatus 12 of an Example is demonstrated.

  In the fluidized bed drying apparatus 12, as shown in FIGS. 1 to 3, raw coal is supplied to the drying container 101 from the raw coal inlet 102, and from the fluidizing gas supply unit through the dispersion plate 108, for example, The fluidized gas 104 (104a, 104b) of superheated steam is supplied to form a fluidized bed S (S1, S2) having a predetermined thickness above the dispersion plate 108. The raw coal of the wet fuel gradually moves the fluidized bed S (S1, S2) to the dry coal discharge port 103 side by the fluidized gas 104 (104a, 104b) in a compacted state, and at this time, from the heat transfer tubes 106a, 106b. It is heated and dried by receiving heat.

In this case, the raw coal is heated and dried by the heat from the heat transfer tubes 106 a and 106 b and the fluidized gas 104 while moving from the raw coal inlet 102 to the dry coal outlet 103. The raw coal just after being put in has a high moisture concentration, and there is a possibility that proper drying becomes difficult.
However, in this embodiment, the inside of the drying container 101 is divided into two in the flow direction of the raw coal into a first drying chamber 111a on the wet fuel input unit 102 side and a second drying chamber 111b on the dry matter discharge unit 103 side, Furthermore, the arrangement ratio of the heat transfer tubes 106a and 106b provided in the first drying chamber 111a and the second drying chamber 111b is set so that the heat transfer tubes 106a in the first drying chamber 111a become rough. Therefore, the raw coal input into the first drying chamber 111a from the raw coal input port 102 is first dried (preliminary drying) in the first drying chamber 111a without clogging between the heat transfer tubes 106a and the like.

The raw coal which has been initially dried in the first drying chamber 111a is pushed away at the opening 113a of the partition plate 113 and gradually flows into the second drying chamber 111b. In the second drying chamber 111b, the raw coal flows in the fluidized bed S2 by the fluidized gas 104b, and is heated by the heat transfer pipe 106b in the fluidized bed S2 and becomes an extruded flow without being diffused in the flow direction. Is done.
In this embodiment, by attaching the fins 130 to the heat transfer tubes, the effect of increasing the heat transfer area can be exhibited, and the plug flow (extrusion flow) property can be improved due to the partition wall effect by the plurality of fins 130. it can.

  Thereafter, the dry coal from which the raw coal has been dried is discharged to the outside from the dry coal discharge port 103, and the steam generated by heating and drying the raw coal in the fluidized beds S1, S2 rises together with the fluidized gas, It flows to the dry coal discharge port 103 side and is discharged to the outside from the gas discharge port 105.

  Thus, in the fluidized bed drying apparatus of the embodiment, the drying container 101 having a hollow shape, the raw coal charging port 102 for charging the raw coal to one end side of the drying container 101, and the other end side of the drying container 101 are provided. Dry coal discharge port 103 that discharges dry coal heated and dried from raw coal, and fluidized gas supply unit that forms fluidized bed S together with raw coal by supplying fluidized gases 104a and 104b to the bottom of drying vessel 101 And dividing the drying container 101 in the moving direction of the wet fuel in the fluidized bed, a gas outlet 105 for discharging fluidized gas and generated steam from above the raw coal inlet 102 on one end side of the drying container 101, At least two or more (two in this embodiment) drying chambers 111a and 111b are formed, and in each of the drying chambers, two or more heat transfer tubes 106a and 106b for heating the wet fuel in the fluidized bed S (S1 and S2), The Ete becomes, a plurality of fins 130 on the heat transfer tube, thereby improving the plug flow due to the partition wall effect.

  Accordingly, the raw coal is introduced into the drying container 101 from the raw coal inlet 102, and the fluidizing gas 104 (104a, 104b) is supplied from the lower part of the drying container 101 through the dispersion plate 108 from the fluidizing gas supply unit. When the raw coal flows by the fluidized gas 104 (104a, 104b), a fluidized bed S (S1, S2) is formed, and when the raw coal in the fluidized bed S moves by the fluidized gas, the heat transfer tube 106a. , 106b is dried to become dry charcoal, and this dry charcoal is discharged to the outside from the dry charcoal discharge port 103. On the other hand, steam generated by drying of the fluidized gas and raw coal is gas discharge port. 105 is discharged to the outside.

At this time, although the raw coal immediately after being input from the raw coal input unit 102 has a large amount of water, the drying container 101 is divided in the moving direction of the wet fuel in the fluidized bed, so that at least two or more drying chambers 111a are obtained. 111b, and two or more heat transfer tubes 106a and 106b for heating the wet fuel in the fluidized bed are provided in each of the drying chambers 111a and 111b, and the heat transfer in the drying chamber 111a on the wet fuel charging portion 102 side is provided. By roughly disposing the heat pipe 106a and increasing the heating temperature of the heat transfer pipe 106a, the raw coal can be pre-dried reliably, while suppressing fluidization failure and adhesion and deposition to the surroundings, the second The drying efficiency of raw coal can be improved by pouring into the drying chamber 111b and performing final drying here.
As a result, it is possible to avoid adhesion, clogging, and poor flow in the drying in the first drying chamber 111a on the inlet side of the wet fuel, and the drying efficiency per unit volume can be improved and the drying apparatus can be made compact and stable. It becomes possible.

In this embodiment, the drying container 101 is divided into two parts. However, the drying container 101 is divided into three parts, the first drying chamber in the preliminary drying region on the raw material introduction side, the second drying chamber in the constant rate drying region adjacent thereto, and the discharge of dry coal. A third drying chamber in the finish drying region on the side is formed, and each of the drying chambers is provided with a heat transfer tube for heating the wet fuel of the fluidized bed S, and among these heat transfer tubes, the second drying chamber in the constant rate drying region A plurality of fins 130 may be installed in the heat transfer tube disposed in the third drying chamber in the finish drying region on the dry coal discharge side.
This is because, in the first drying chamber in the preliminary drying region on the raw material introduction side, it is preferable to improve the preliminary drying of the wet raw material with emphasis on fluidity rather than the effect of plug flow.

Here, in this embodiment, the floor area ratio between the first drying chamber 111a and the second drying chamber 111b is set to ½, but the present invention is not limited to this, and the ratio may be changed as appropriate. It may be.
This is an optimal ratio is set according to the raw coal processing amount, for example, when the raw coal processing amount is large, it is preferable to widen the constant rate drying region of the second drying chamber 111b, Set as appropriate.

DESCRIPTION OF SYMBOLS 11 Coal feeder 12 Fluidized bed dryer 13 Pulverized coal machine 14 Coal gasifier 15 Char recovery device 16 Gas refiner 17 Gas turbine equipment 18 Steam turbine equipment 19 Generator 20 Waste heat recovery boiler 101 Drying vessel 102 Raw coal input (Wet fuel input part)
103 Dry coal discharge port (dry matter discharge part)
104 (104a, 104b) Fluidized gas 105 Gas outlet (gas outlet)
106a, 106b Heat transfer tube (heating unit)
111a 1st drying chamber 111b 2nd drying chamber 111c 3rd drying chamber 113 Partition plate 130 Fin F (F1, F2) Free board part S (S1, S2) Fluidized bed

Claims (2)

A drying container having a hollow shape;
A wet fuel charging unit for charging wet fuel to one end of the drying container;
A dry matter discharge unit for discharging dry matter obtained by heating and drying wet fuel from the other end of the drying container;
A fluidized steam or fluidized gas supply unit that forms a fluidized bed with wet fuel by supplying fluidized steam or fluidized gas to a lower portion of the drying container;
A gas discharge part for discharging fluidized steam or fluidized gas and generated steam from above the drying container;
Dividing the drying container in the moving direction of the wet fuel in the fluidized bed to form at least two drying chambers, each of the drying chambers comprising a heat transfer tube for heating the wet fuel in the fluidized bed;
The heat transfer tubes disposed in the drying chambers are inserted from a direction perpendicular to the traveling direction of the dried material, and fins are installed in the vertical axis direction with a predetermined interval to the heat transfer tubes. Fluidized bed drying device. A fluidized bed drying apparatus according to claim 1;
A coal gasification furnace that processes the dry coal supplied from the fluidized bed drying device and converts 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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