AU2013200899A1 - Fluid bed drying apparatus, gasification combined power generating facility, and pulverized fuel supply method - Google Patents

Abstract

Abstract There is provided a fluid bed drying apparatus including: a drying container which has a rectangular inner space formed in a height direction along a vertical direction and length and width directions perpendicular to the height direction, and forms a fluid bed in the inner space by fluidizing a pulverized fuel input to the inner space through a fluidizing gas; a pulverized fuel input portion for inputting the pulverized fuel from one end side of the drying container in the length direction; a first fuel dispersion portion for dispersing the pulverized fuel input from the pulverized fuel input portion in the length direction of the inner space of the drying container; and a control device for controlling the first fuel dispersion portion. FLUID BED DRYING BROWN COAL APPARTUS INPUT PORTION 43J 51 ...................

Description

1 FLUID BED DRYING APPARATUS, GASIFICATION COMBINED POWER GENERATING FACILITY, AND PULVERIZED FUEL SUPPLY METHOD CROSS-REFERENCE TO RELATED APPLICATIONS This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2012 035575 filed February 21, 2012, the entire contents of which are incorporated herein by reference. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid bed drying apparatus, a gasification combined power generating facility, and a pulverized fuel supply method of drying a pulverized fuel such as brown coal in a flowing state. 2. Description of the Related Art There is conventionally known a fuel dispersion supply device which supplies highly moistened residues supplied from a fuel supply pipe in a dispersion state (for example, see Japanese Patent Application Laid-open No. 2-213609). The fuel dispersion supply device includes a rotor and toothed blades which are fixed to the circumference of the rotor at the same pitch. The fuel dispersion supply device disperses and supplies the fuel by rotating the rotor. Further, the rotor is of a variable speed type, and a discharge arrival distance is adjusted by changing a rotation speed according to the type of fuel. Here, in the conventional fuel dispersion supply device, when a predetermined fuel is supplied by changing the rotation speed of the rotor according to the type of fuel, the rotation speed of the rotor becomes a predetermined rotation speed. That is, in the conventional fuel dispersion supply device, the fuel may be dispersed by 2 rotating the toothed blades at a predetermined rotation speed by the rotor. However, in the conventional fuel dispersion supply device, it is difficult to improve the fuel dispersion efficiency since the rotor is rotated at a predetermined rotation speed. SUMMARY OF THE INVENTION According to a first aspect of the present invention, there is provided a fluid bed drying apparatus including: a drying container which has a rectangular inner space formed in a height direction along a vertical direction and length and width directions perpendicular to the height direction, and forms a fluid bed in the inner space by fluidizing a pulverized fuel input to the inner space through a fluidizing gas; a pulverized fuel input portion for inputting the pulverized fuel from one end side of the drying container in the length direction; a first fuel dispersion portion for dispersing the pulverized fuel input from the pulverized fuel input portion in the length direction of the inner space of the drying container; and a control device for controlling the first fuel dispersion' portion, wherein the first fuel dispersion portion includes a first rotary shaft having an axial direction which corresponds to the width direction, a plurality of first dispersion blades provided at a predetermined interval in a circumferential direction of the first rotary shaft, and a first driving device for rotating the first rotary shaft, wherein the control device is configured to control the first driving device so as to change a rotation speed of the first rotary shaft at a predetermined cycle, According to a second aspect of the present invention, there is provided a gasification combined power generating facility including: the fluid bed drying apparatus 3 according to the first aspect; a gasification furnace for treating the dried wet fuel supplied from the fluid bed drying apparatus so that the fuel is changed into a gasified gas; a gas turbine which is operated by using the gasified gas as fuel; a steam turbine which is operated by steam produced by an exhausted heat recovery boiler into which a turbine flue gas is introduced from the gas turbine; and a generator which is connected to the gas turbine and the steam turbine. According to a third aspect of the present invention, there is provided a pulverized fuel supply method including: supplying a pulverized fuel into a drying container with a rectangular inner space formed in a height direction along a vertical direction and length and width directions perpendicular to the height direction, wherein the drying container is provided with a first fuel dispersion portion that includes a first rotary shaft of which the axial direction becomes the width direction, a plurality of first dispersion blades which are provided at a predetermined interval in a circumferential direction of the first rotary shaft, and a first driving device which rotates the first rotary shaft, and wherein the pulverized fuel supply method further comprising: inputting the pulverized fuel toward the first fuel dispersion portion while controlling the first driving device with the control device so as to change the rotation speed of the first rotary shaft at a predetermined cycle. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic configuration diagram of a coal gasification combined power generating facility which adopts a fluid bed drying apparatus according to a first embodiment; 4 FIG. 2 is a perspective view schematically illustrating the fluid bed drying apparatus according to the first embodiment; FIG. 3 is a cross-sectional view schematically illustrating the fluid bed drying apparatus according to the first embodiment in the side view; FIG. 4 is a cross-sectional view schematically illustrating the fluid bed drying apparatus according to the first embodiment in the front view; FIG. 5 is a graph illustrating cycles of rotation speeds of a first rotary shaft and a second rotary shaft of the fluid bed drying apparatus according to the first embodiment; FIG. 6 is a cross-sectional view schematically illustrating a fluid bed drying apparatus according to a second embodiment in the side view; FIG. 7 is a cross-sectional view schematically illustrating the fluid bed drying apparatus according to the second embodiment in the front view; and FIG. 8 is a schematic configuration diagram roughly illustrating a dispersion blade according to a first modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a fluid bed drying apparatus, a gasification combined power generating facility, and a pulverized fuel supply method according to the invention will be described by referring to the accompanying drawings. Incidentally, the invention will not be limited to the following embodiment. Further, the components in the following embodiments include a component which may be easily replaced by the person skilled in the art or a component which has substantially the same configuration.

5 It is an object of embodiments to provide a fluid bed drying apparatus, a gasification combined power generating facility, and a pulverized fuel supply method capable of appropriately dispersing a pulverized fuel. [First embodiment] FIG. I is a schematic configuration diagram of a coal gasification combined power generating facility which adopts a fluid bed drying apparatus according to a first embodiment. A coal gasification combined power generating facility (IGCC: Integrated Coal Gasification Combined Cycle) 100 which adopts a fluid bed drying apparatus 1 of the first embodiment adopts an air combustion type in which a coal gas is produced in a gasification furnace by using air as an oxidation agent, and supplies the coal gas purified by a gas purification device as a fuel gas to a gas turbine facility so as to generate power. That is, the coal gasification combined power generating facility 100 of the first embodiment is a power generating facility of an air combustion (air blow) type. In this case, brown coal is used as a pulverized fuel to be supplied to the gasification furnace. Furthermore, in the first embodiment, brown coal is employed as the pulverized fuel, but low-grade coal including subbituminous coal or peat such as sludge may be employed. Further, high-grade coal may be also employed. Further, the pulverized fuel is not limited to coal such as brown coal, and biomass which is used as a renewable biological organic resource may be employed. For example, thinned wood, waste wood, driftwood, grass, waste, mud, a tire, and a recycled fuel (pellet or chip) produced therefrom may be employed. In the first embodiment, as illustrated in Fig. 1, the 6 coal gasification combined power generating facility 100 includes a coal supply device 111, the fluid bed drying apparatus 1, a coal pulverizer (mill) 113, a coal gasification furnace 114, a char recovery unit 115, a gas purification device 116, a gas turbine facility 117, a steam turbine facility 118, a generator 119, and an exhausted heat recovery boiler (HRSG: Heat Recovery Steam Generator) 120. The coal supply device 111 includes a raw coal bunker 121, a coal feeder 122, and a crusher 123. The raw coal bunker 121 can store brown coal, and inputs a predetermined amount of brown coal into the coal feeder 122. The coal feeder 122 conveys the brown coal input from the raw coal bunker 121 by a conveyor or the like, and inputs the brown coal into the crusher 123. The crusher 123 crushes the input brown coal finely so that the brown coal becomes grains. Although it will be described below, the fluid bed drying apparatus 1 removes the moisture content included in the brown coal by drying the brown coal input from the coal supply device 111 while the brown coal flows by a fluidizing gas. The fluid bed drying apparatus 1 is connected with a cooler 131 which cools the dry brown coal (the dry coal) discharged therefrom. The cooler 131 is connected with a dry coal bunker 132 which stores the cooled dry coal. Further, the fluid bed drying apparatus 1 is connected with a dry coal cyclone 133 and an electric dry coal dust collector 134 as a dust collecting device 139 which separates dry coal particles from the exhaust gas discharged to the outside. The particles of the dry coal separated from the exhaust gas in the dry coal cyclone 133 and the electric dry coal dust collector 134 are stored in the dry coal bunker 132. Furthermore, the exhaust gas from 7 which the dry coal is separated by the electric dry coal dust collector 134 is compressed by a steam compressor 135 and is used as various heat sources. A coal pulverizer 113 produces pulverized coal by crushing the brown coal (the dry coal) dried by the fluid bed drying apparatus 1 into fine particles. That is', when the dry coal stored in the dry coal bunker 132 is input to the coal pulverizer 113 by a coal feeder 136, the coal pulverizer pulverizes the dry coal into pulverized coal having a predetermined particle diameter or less. Then, the pulverized coal which is pulverized by the coal pulverizer 113 is separated' from the carrier gas by pulverized coal bag filters 137a and 137b and is stored in pulverized coal supply hoppers 138a and 138b. To the coal gasification furnace 114, the pulverized coal which is processed by the coal pulverizer 113 is supplied and char (the unburned portion of coal) which is collected by the char recovery unit 115 is supplied. The coal gasification furnace 114 is connected with a compressed air supply line 141 from the gas turbine facility 117 (compressor 161), so that the air compressed by the gas turbine facility 117 may be supplied thereto. The air separating device 142 is used to produce separate nitrogen and oxygen from the air in the atmosphere, a first nitrogen supply line 143 is connected to the coal gasification furnace 114, and the first nitrogen supply line 143 is connected with coal supply lines 144a and 144b from the pulverized coal supply hoppers 138a and 138b. Further, the second nitrogen supply line 145 is also connected to the coal gasification furnace 114, and the second nitrogen supply line 145 is connected with a char return line 146 from the char recovery unit 115. Further, an oxygen supply line 147 is connected to the compressed 8 air supply line 141. In this case, the nitrogen is used as a carrier gas for the coal and the char, and the oxygen is used as an oxidation agent. The coal gasification furnace 114 is, for example, an, entrained bed gasification furnace, and is used to burn and gasify the coal, the char, air (the oxygen), or the steam as the gasifying agent supplied thereinto and generates a combustible gas (a product gas and a coal gas) mainly including carbon dioxide, so that a gasification reaction occurs using the combustible gas as a gasifying agent. Furthermore, the coal gasification furnace 114 is provided with a foreign matter removing device 148 which removes foreign matter mixed with the pulverized coal. In this case, the coal gasification furnace 114 is not limited to the entrained bed gasification furnace, and may be also a fluid bed gasification furnace or a fixed bed gasification furnace. Then, in the coal gasification furnace 114, a combustible gas generation line 149 is installed toward the char recovery unit 115, so that the combustible gas including the char may be discharged therethrough. In this case, the gas generation line 149 may be provided with a gas cooler, and the combustible gas may be cooled to a predetermined temperature and be supplied to the char recovery unit 115. The char recovery unit 115 includes a dust collecting device 151 and a supply hopper 152. In this case, the dust collecting device 151 includes one or plural bag filters or cyclones, and hence may separate the char included in the combustible gas produced by the coal gasification furnace 114. Then, the combustible gas from which the char is separated is sent to the gas purification device 116 through a gas discharge line 153. The supply hopper 152 is used to store the char separated from the combustible gas 9 in the dust collecting device 151. Furthermore, a bin may be disposed between the dust collecting device 151 and the supply hopper 152 and a plurality of the supply hoppers 152 may be connected to the bin. Then, the char return line 146 from the supply hopper 152 is connected to the second nitrogen supply line 145. The gas purification device 116 performs gas purification on the combustible gas from which the char is separated by the char recovery unit 115 by removing impurities such as a sulfur compound or a nitrogen compound. Then, the gas purification device 116 produces a fuel gas by purifying the combustible gas and supplies the result to the gas turbine facility 117. Furthermore, in the gas purification device 116, since a sulfur content (H2S) is still included in the combustible gas from which the char is separated, the sulfur content is finally collected as gypsum by the removal using amines absorbent and is effectively used. The gas turbine facility 117 includes the compressor 161, a combustor 162, and a turbine 163, and the compressor 161 and the turbine 163 are connected to each other by a rotary shaft 164. The combustor 162 is connected with a compressed air supply line 165 from the compressor 161, and is connected with a fuel gas supply line 166 from the gas purification device 116, so that the turbine 163 is connected with a combustion gas supply line 167. Further, the gas turbine facility 117 is provided with the compressed air supply line 141 which extends from the compressor 161 to the coal gasification furnace 114, and the compressed air supply line 141 is provided with a booster 168. Accordingly, in the combustor 162, the compressed air supplied from the compressor 161 is mixed with the fuel gas supplied from the gas purification device 10 116 and is burned. Thus, in the turbine 163, the generator 119 may be driven by rotating the rotary shaft 164 by the produced combustion gas. The steam turbine facility 118 includes a turbine 169 which is connected to the rotary shaft 164 in the gas turbine facility 117, and the generator 119 is connected to the base end of the rotary shaft 164. The exhausted heat recovery boiler 120 is provided in a flue gas line 170 from the gas turbine facility 117 (the turbine 163), and is used to produce steam by the heat exchange between air and the high-temperature flue gas. For this reason, a steam supply line 171 and a steam recovery line 172 are provided between the exhausted heat recovery boiler 120 and the turbine 169 of the steam turbine facility 118, and a condenser 173 is provided in the steam recovery line 172. Accordingly, in the steam turbine facility 118, the turbine 169 is driven by the steam supplied from the exhausted heat recovery boiler 120, and the generator 119 may be driven by the rotation of the rotary shaft 164. Then, the flue gas of which the heat is collected in the exhausted heat recovery boiler 120 passes through the gas purification device 174 so as to remove a toxic material therefrom, and the purified flue gas is discharged from a stack 175 to the atmosphere. Here, an operation of the coal gasification combined power generating facility 100 of the first embodiment will be described. According to the coal gasification combined power generating facility 100 of the first embodiment, in the coal supply device 111, the raw coal (brown coal) is stored in the raw coal bunker 121, and the brown coal of the raw coal bunker 121 is input to the crusher 123 by the coal feeder 122 so that the brown coal is pulverized into a 11 predetermined size. 'Then, the pulverized brown coal is heated and dried by the fluid bed drying apparatus 1, is cooled by the cooler 131, and is stored in the dry coal bunker 132. Further, the steam which is extracted from the upper portion of the fluid bed drying apparatus 1 passes through the dry coal cyclone 133 and the electric dry coal dust collector 134 so that the particles of the dry coal are separated, and the result is compressed by the steam compressor 135, so that the dry coal is used as various heat sources. Meanwhile, the particles of the dry coal separated from the steam are stored in the dry coal bunker 132. The dry coal which is stored in the dry coal bunker 132 is input to the coal pulverizer 113 by the coal feeder 136. Here, the dry coal is pulverized into fine particles to thereby produce the pulverized coal, and is stored in the pulverized coal supply hoppers 138a and 136b through the pulverized coal bag filters 137a and 137b. The pulverized coal which is stored in the pulverized coal supply hoppers 13Ba and 138b is supplied to the coal gasification furnace 114 through the first nitrogen supply line 143 by the nitrogen supplied from the air separating device 142. Further, the char which is collected by the char recovery unit 115 to be described later is supplied to the coal gasification furnace 114 through the second nitrogen supply line 145 by the nitrogen supplied from the air separating device 142. Further, the compressed air which is extracted from the gas turbine facility 117 to be described later is boosted by the bboster 168, and is supplied to the coal gasification furnace 114 through the compressed air supply line 141 along with the oxygen supplied from the air separating device 142. In the coal gasification furnace 114, the supplied 12 pulverized coal and char are burned by the compressed air (the oxygen), and the pulverized coal and the char are gasified, thereby producing the combustible gas (the coal gas) mainly including carbon dioxide. Then, the combustible gas is discharged from the coal gasification furnace 114 through the gas generation line 149 and is sent to the char recovery unit 115. In the char recovery unit 115, the combustible gas is first supplied to the dust collecting device 151, and the dust collecting device 151 separates the char included in the combustible gas. Then, the combustible gas from which the char is separated is sent to the gas purification device 116 through the.gas discharge line 153. Meanwhile, the fine char which is separated from the combustible gas is deposited on the supply hopper 152, and is returned to the coal gasification furnace 114 through the char return line 146 so as to be recovered. The combustible gas from which the char is separated by the char recovery unit 115 passes through the gas purification device 116 so that impurities such as a sulfur compound or a nitrogen compound are removed and the gas is purified, thereby producing a fuel gas. Then, in the gas turbine facility 117, when the compressor 161 produces the compressed air and supplies the compressed air to the combustor 162, the combustor 162 mixes the compressed air supplied from the compressor 161 with the fuel gas supplied from the gas purification device 116 and burns the mixed result to thereby produce a combustion gas. Then, the turbine 163 is driven by the combustion gas, and the generator 119 is driven through the rotary shaft 164, thereby generating power. Then, the flue gas which is discharged from the turbine 163 in the gas turbine facility 1 exchanges heat 13 with air in the exhausted heat recovery boiler 120 so as to produce steam, and the produced steam is supplied to the steam turbine facility 118. In the steam turbine facility 118, the turbine 169 is driven by the steam supplied from the exhausted heat recovery boiler 120, and hence power may be generated by driving the generator 119 through the rotary shaft 164. Subsequently, in the gas purification device 174, the flue gas which is purified by removing the toxic material of the flue gas discharged from the exhausted heat recovery boiler 120 is discharged to the atmosphere from the stack 175. Hereinafter, the fluid bed drying apparatus 1 of the coal gasification combined power generating facility 100 described above will be described in detail. FIG. 2 is a perspective view schematically illustrating the fluid bed drying apparatus according to the first embodiment. FIG. 3 is a cross-sectional view schematically illustrating the fluid bed drying apparatus according to the first embodiment in the side view. FIG. 4 is a cross-sectional view schematically illustrating the fluid bed drying apparatus.according to the first embodiment in the front view. The fluid bed drying apparatus 1 of the first embodiment is used to heat and dry the brown coal input by the coal supply device 111 while the brown coal flows by the fluidizing gas. As illustrated in FIGS. 2 to 4, the fluid bed drying apparatus 1 includes a drying container 5 into which brown coal is supplied and a gas dispersion plate 6 which is provided inside the drying container 5. The drying container 5 is formed in a rectangular box shape. That is, the drying container 5 has a rectangular inner space which is formed in the length direction, the width direction, and 14 the height direction. The gas dispersion plate 6 divides the inner space of the drying container 5 into a blowing chamber 11 which is positioned at the lower side (the lower side in the drawing) in the vertical direction and a drying chamber 12 which is positioned at the upper side (the upper side in the drawing) in the vertical direction. The gas dispersion plate 6 is provided with a plurality of penetration holes, and a fluidizing gas such as steam is introduced into the blowing chamber 11. The drying chamber 12 of the drying container 5 is provided with a brown coal input portion (a pulverized fuel input portion) 31 into which brown coal is input, a dry coal discharge port 34 through which dry coal obtained by heating and drying brown coal is discharged, and a gas discharge port 35 through which a fluidizing gas and steam produced in the drying state are discharged. Although it will be described later, the brown coal input portion 31 is formed at the upper portion of one end side (the left side in the drawing) of the drying chamber 12 in the length direction. The coal supply device 111 is connected to the brown coal input portion 31, and the brown coal supplied from the coal supply device 111 is supplied to the drying chamber 12. The dry coal discharge port 34 is formed at the lower portion of the other end side (the right side in the drawing) of the drying chamber 12 in the length direction. The brown coal which is dried in the drying chamber 12 is discharged as the dry coal from the dry coal discharge port 34, and the discharged dry coal is supplied to the cooler 131. The gas discharge port 35 is formed at the upper portion of the other end side of the drying chamber 12 in the length direction. The gas discharge port 35 discharges 15 the steam produced by heating the brown coal along with the fluidizing gas supplied to the drying chamber 12 when drying the brown coal. Furthermore, the fluidized steam and the produced steam discharged from the gas discharge port 35 are supplied toward the dust collecting device 139 described above, and are supplied to the steam compressor 135. Accordingly, the brown coal which is supplied to the drying chamber 12 through the brown coal input portion 31 is fluidized by the fluidizing gas supplied through the gas dispersion plate 6, so that the fluid bed 3 is formed in the entire area inside the drying chamber 12 and the freeboard F is formed above the fluid bed 3. The flow direction of the fluid bed 3 which is formed in the drying chamber 12 becomes a direction from one end side of the drying chamber 12 toward the other end side thereof. The input brown coal is dried while flowing along the flow direction, so that the water content included in the brown coal becomes the produced steam and is discharged from the gas discharge port 35 along with the fluidizing gas. The brown coal from which the water content is removed and which flows to the other end side of the drying chamber 12 is discharged as the dry coal from the dry coal discharge port 34. Next, the brown coal input portion 31 will be described by referring to FIGS. 2 to 4. The brown coal input portion 31 includes a brown coal input chamber 41 which communicates with the drying chamber 12 and a brown coal input passageway 42 which is connected to the brown coal input chamber 41. Further, the brown coal input chamber 41 is provided with a first fuel dispersion portion 43 which disperses the brown coal in the length direction of the inner space of the drying container 5 and a second 16 fuel dispersion portion 44 which disperses the brown coal in the width direction of the inner space of the drying container 5. The brown coal input chamber 41 is. formed in a rectangular box shape, is provided at the upper portion of one end side of the drying chamber 12 in the length direction, and is provided so as to extend in the width direction of the drying chamber 12. The brown coal is temporarily stored in the brown coal input chamber 41, and the stored brown coal is supplied from the brown coal input chamber 41 to the drying chamber 12 by the first fuel dispersion portion 43. The brown coal input passageway 42 is provided at the upper portion of one end side (the front side in the drawing) of the brown coal input chamber 41 in the width direction. The brown coal input passageway 42 guides the brown coal supplied from the coal supply device 111 to the brown coal input chamber 41. The first fuel dispersion portion 43 includes a first rotary shaft 51 of which the width direction is set as the axial direction and a plurality of first dispersion blades 52 which are provided in the first rotary shaft 51, and a first driving device 21 is connected to the first rotary shaft 51. Further, the first driving device 21 is controlled by a control device 63. For this reason, the control device 63 may control the rotation of the first rotary shaft 51 by controlling the first driving device 21. Furthermore, the control device 63 may be a control panel which is provided in the coal gasification combined power generating facility 100, and may be also a control panel which is provided in the fluid bed drying apparatus 1. The first rotary shaft 51 is provided at the lower side of the brown coal input chamber 41, that is, between 17 the brown coal input chamber 41 and the drying chamber 12 and is disposed in the entire width of the drying chamber 12. The rotation direction of the first rotary shaft 51 becomes a direction from one end side toward the other end side in the length direction at the lower side, and becomes a direction from the other end side toward one end side in the length direction at the upper side. That is, the rotation direction of the first rotary shaft 51 becomes the counter-clockwise direction in FIGS. 2 and 3. The first rotary shaft 51 is connected to the first driving device 21, so that the rotation speed is controlled by the control device 63. The plurality of first dispersion blades 52 are provided at a predetermined interval in the circumferential direction of the first rotary shaft 51. Each first dispersion blade 52. is formed in a plane shape, and is provided so as to extend in the axial direction (the width direction) of the first rotary shaft 51. For this reason, in each first dispersion blade 52, the length from the base end side to the front end side in the radial direction of the first rotary shaft 51 becomes the same length in the width direction. That is, the front end side of each first dispersion blade 52 becomes a plane in the axial direction. Further, in the plurality of first dispersion blades 52, the lengths in the radial direction of the first rotary shaft 51 are equal to each other. Furthermore, in the first embodiment, each first dispersion blade 52 is formed in a plane shape, but the invention is not limited thereto. For example, the blade may be formed in a comb shape. Then, the first fuel dispersion portion 43 regulates the input of the brown coal into the drying chamber 12 by positioning the first rotary shaft 51 and the plurality of first dispersion blades 52 between the brown coal input 18 chamber 41 and the drying chamber 12, and temporarily stores the brown coal in the brown coal input chamber 41. Further, the first fuel dispersion portion 43 rotates the first rotary shaft 51 by the first driving device 21, so that the plurality of first dispersion blades 52 captures the stored brown coal and inputs the captured brown coal into the drying chamber 12 from one end side toward the other end side in the length direction at the lower side of the first rotary shaft 51. The second fuel dispersion portion 44 includes a second rotary shaft 61 of which the length direction is set as the axial direction and a plurality of second dispersion blades 62 which are provided in the second rotary shaft 61, and a second driving device 53 is connected to the second rotary shaft 61. Further, the second driving device 53 is controlled by the control device 63. For this reason, the control device 63 may control the rotation of the second rotary shaft 61 by controlling the second driving device 53. The second rotary shaft 61 is provided at the inside of one end side of the brown coal input chamber 41 in the width direction. That is, the second rotary shaft 61 is provided directly below the brown coal input passageway 42 and is provided directly above the first fuel dispersion portion 43. The rotation direction of the second rotary shaft 61 becomes a direction from one end side (the front side of the drawing) toward the other end side (the inner side of the drawing) in the width direction at the lower side, and becomes a direction from the other end side toward one end side in the width direction at the upper side, That is, the rotation direction of the second rotary shaft 61 becomes the counter-clockwise direction in FIG. 4. The second rotary shaft 61 is connected to the second driving device 53 described above, so that the rotation 19 speed is controlled by the control device 63. The plurality of second dispersion blades 62 are provided at a predetermined interval in the circumferential direction of the second rotary shaft 61. Each second dispersion blade 62 is formed in a plane shape, and is provided so as to extend in the axial direction (the length direction) of the second rotary shaft 61. For this reason, in each second dispersion blade 62, the length from the base end side to the front end side in the radial direction of the second rotary shaft 61 becomes the same-length in the width direction. Further, in the plurality of second dispersion blades 62, the lengths in the radial direction of the second rotary shaft 61 are equal to each other. Furthermore, in the first embodiment, each second dispersion blade 62 is formed in a plane shape, but as in the first dispersion blade 52, the shape is not limited thereto. For example, the blade may be formed in a comb shape. Then, in the second fuel dispersion portion 44, the second rotary shaft 61 and the plurality of second dispersion blades 62 are positioned directly below the brown coal input passageway 42, the second rotary shaft 61 is rotated by the second driving device 53 so that the plurality of second dispersion blades 62 capture the brown coal input from the brown coal input passageway 42, and the captured brown coal is input to the brown coal input chamber 41 from one end side toward the other end side in the width direction at the lower side of the second rotary shaft 61. Next, the control device 63 will be described by referring to FIG. 5. FIG, 5 is a graph illustrating cycles of the rotation speeds of the first rotary shaft and the second rotary shaft of the fluid bed drying apparatus 20 according to the first embodiment. The control device 63 is connected to the first driving device 21 and the second driving device 53, and controls the rotation speeds of the first rotary shaft 51 and the second rotary shaft 61. Specifically, the control device 63 periodically changes the rotation speeds of the first rotary shaft 51 and the second rotary shaft 61. The predetermined cycle becomes, for example, a sine curve L1 of FIG. 5, and the control device 63 changes the rotation speeds of the first rotary shaft 51 and the second rotary shaft 61 according to the sine curve L1. The sine curve L1 becomes a curve in which the rotation speed continuously changes between a fast rotation speed and a slow rotation speed. Thus, the rotation speed of the first rotary shaft 51 of the first fuel dispersion portibn 43 and the rotation speed of the second rotary shaft 61 of the second fuel dispersion portion 44 continuously change between a slow rotation speed and a fast rotation speed. Here, when the brown coal is supplied to the drying chamber 12 while the rotation speed of the first rotary shaft 51 of the first fuel dispersion portion 43 is slow, the speed of the brown coal decreases, so that the brown coal drops to one end side in the length direction, that is, the position close to the first fuel dispersion portion 43. On the other hand, when the brown coal is supplied to the drying chamber 12 while the rotation speed of the first rotary shaft 51 of the first fuel dispersion portion 43 is fast, the speed of the brown coal increases, so that the brown coal drops to the other end side in the length direction, that is, the position away from the first fuel dispersion portion 43. Similarly, when the brown coal is supplied to the brown coal input chamber 41 while the rotation speed of the second rotary shaft 61 of the second fuel dispersion 21 portion 44 is slow, the speed of the brown coal decreases, so that the brown coal drops to one end side in the width direction, that is, the position close to the second fuel dispersion portion 44. On the other hand, when the brown coal is supplied to the brown coal input chamber 41 while the rotation' speed of the second rotary shaft 61 of the' second fuel dispersion portion 44 is fast, the speed of the brown coal increases, so that the brown coal drops to the other end side in the width direction, that is, the position away from the second fuel dispersion portion 44. Accordingly, when the rotation speed of the first rotary shaft 51 of the first fuel dispersion portion 43 is changed by the control device 63 according to the sine curve Li, the brown coal is continuously input between one end side and the other end side in the length direction. Thus, the first fuel dispersion portion 43 may input the brown coal in a dispersion state in the length direction of the drying chamber 12. Further, as in the first fuel dispersion portion 43, when the rotation speed of the second rotary shaft 61 of the second fuel dispersion portion 44 is changed by the control device 63 according to the sine curve LI, the brown coal is continuously input between one end side and the other end side in the width direction. Thus, the second fuel dispersion portion 44 may disperse the brown coal in the width direction of the brown coal input chamber 41, and the brown coal dispersed in the width direction is dispersed in the length direction of the first fuel dispersion portion 43, thereby evenly supplying the brown coal into the inner space of the rectangular box-shaped drying chamber 12. In this way, according to the configuration of the first embodiment, since the rotation speed of the first 22 rotary shaft 51 may be changed at a predetermined cycle, the brown coal may be dispersed between the near position and the far position in the length direction of the drying chamber 12 even when the front end side of the first dispersion blade 52 is flat. Further, similarly, since the rotation speed of the second rotary shaft 61 may be changed at a predetermined cycle, the brown coal may be dispersed between the near position and the far position in the width direction of the brown coal input chamber 41 even when the front and side of the second dispersion blade 62 is flat. Furthermore, in the first embodiment, the control device !63 periodically changes the rotation speeds of the first rotary shaft 51 and the second rotary shaft 61 according to the sine curve Ll of FIG. 5, but may periodically change the rotation speed of the first rotary shaft 51 according to the curve L2 of FIG. 5. Here, the curve 12 becomes a curve in which the rotation speeds of the first rotary shaft 51 and the second rotary shaft 61 continuously change between a fast rotation speed and a slow rotation speed, and the time of the fast rotation speed is longer than that of the slow rotation speed. Accordingly, when the rotation speed of the first rotary shaft 51 of the first fuel dispersion portion 43 is changed according to the curve L2 by the control device 63, the brown coal is continuously input between one end side and the other end side in the length direction. At this time, since the time of the fast rotation speed is longer than that of the slow rotation speed, the first fuel dispersion portion 43 supplies more brown coal toward the other end side (the far position) in relation to one end side (the near position) in the length direction. Thus, since the first fuel dispersion portion 43 may supply more brown coal toward the far position of the drying chamber 12 23 when tha brown coal easily drops to the near position of the dry ng chamber 12, the brown coal may be input while being d spersed in the length direction of the drying chamber 12. similarly, the second fuel dispersion portion 44 contiLnuously inputs the brown coal between one end side and the other end side in the width direction when the rotation speed of the second rotary shaft 61 is changed according to the curve L2 by the control device 63. At this tipe, since the time of the fast rotation speed is longer than that of the slow rotation speed, the second fuel dispersion portion 44 supplies more brown coal toward the oter end side (the far position) in relation to one end since (the near position) in the width direction. Thus, since the second fuel dispersion portion 44 may supply more brown coal toward the far position of the brown coal input chamber 41 when the brown coal easily drops to the near position of the brown coal input chamber 41, the brown coal may be input while being dispersed in the width direction of the brown coal input chamber 41. F rather, in the first embodiment, the sine curve L1 and the curve L2 are exemplified as the predetermined cycle, but tb invention is not limited to the configuration. That is, the predetermined cycle may be changed in response to the specific weight of the input brown coal. Here, the specific weight of the brown coal changes by the type of brown coal, the water content ratio of brown coal, and the like. For this reason, since the first fuel dispersion portion 43 and the second fuel dispersion portion 44 change the rc tation speeds of the first rotary shaft 51 and the second rotary shaft 61 by the control device 63 based on the predetermined cycle corresponding to the specific weight of the brown coal, various kinds of brown coal may be supplied while being appropriately dispersed in the 24 length direction. [Second embodiment] Next, a fluid bed drying apparatus 200 according to a second embodiment will be described by referring to FIGS. 6 and 7. FIG. 6 is a cross-sectional view schematically illustrating the fluid bed drying apparatus according to the second embodiment in the side view. FIG. 7 is a cross sectional view schematically illustrating the fluid bed drying -apparatus according to the second embodiment in the front view. Furthermore, in the second embodiment, the difference from the first embodiment will be described so as to prevent the repetitive description, and the same component as that of the first embodiment will be denoted by the same letter or numeral. In the fluid bed drying apparatus 1 according to the first embodiment, the second fuel dispersion portion 44 includes the second rotary shaft 61 and the plurality of second dispersion blades 62. However, in the fluid bed drying apparatus 200 according to the second embodiment, a second fuel dispersion portion 205 is configured as a brown coal input chamber 206 which serves as a dispersion container. Hereinafter, the fluid bed drying apparatus 200 according to the second embodiment will be described. As illustrated in FIG. 7, in the fluid bed drying apparatus 200 according to the second embodiment, the brown coal input chamber 206 is formed in a trapezoidal box shape which is widened in the width direction from the, upside toward the downside in the height direction, and a top portion 206a is formed so that the height at the center in the width direction is the highest. The brown coal input chamber 206 is provided at the upper portion of one end side in the length direction of the drying chamber 12, and 25 extends in the width direction of the drying chamber 12. The brown coal input passageway 42 is connected to the top portion 206a of the brown coal input chamber 206 so as to communicate therewith, and the drying chamber 12 is connected to a bottom portion 206b of the brown coal input chamber 206 so as to communicate therewith. For this reason, in the second embodiment, as illustrated in FIG. 6, the second rotary shaft 61 and the plurality of second dispersion blades 62 of the first embodiment may not be provided, and the configuration may be simplified. Accordingly, when the brown coal is input from the brown coal input passageway 42, the input brown coal passes through the brown coal input chamber 206 so as to be accumulated while being widened in the width direction with respect to the brown coal input passageway 42. Thus, the second fuel dispersion portion 205 may disperse the brown coal in the width direction of the brown coal input chamber 206, and the brown coal dispersed in the width direction is dispersed in the length direction of the first fuel dispersion portion 43, thereby evenly supplying the brown coal into the inner space of the rectangular box-shaped drying chamber 12. In this way, even in the configuration of the second embodiment, the brown coal may be dispersed in the width direction by causing the brown coal to pass through the brown coal input chamber 206. Further, the second rotary shaft 61 and the plurality of second dispersion blades 62 of the first embodiment may not be provided, and the configuration may be simplified. Furthermore, in the first embodiment and the second embodiment, the plurality of first dispersion blades 52 and the plurality of second dispersion blades 62 have the same length in the radial direction of the first rotary shaft 51 26 and the second rotary shaft 61, but may have the configuration illustrated in the first modified example of FIG. 8. FIG. 8 is a schematic configuration diagram roughly illustrating a dispersion blade according to a first modified example. As illustrated in FIG. 8, the plurality of first dispersion blades 52 have different lengths in the radial direction of the first rotary shaft 51. That is, in the plurality of first dispersion blades 52, the length of one first dispersion blade 52 in the radial direction is longer or shorter than the length of the other first dispersion blade 52 in the radial direction. Furthermore, the plurality of first dispersion blades 52 may be provided at a predetermined interval in the circumferential direction so that the length in the radial direction is gradually shortened or the length in the radial direction is gradually lengthened in the passage order from the lower side of the first rotary shaft 51. Similarly, the plurality of second dispersion blades 62 have different lengths in the radial direction of the second rotary shaft 61. Furthermore, since the plurality of second dispersion blades 62 are identical to the plurality of first dispersion blades 52, the description thereof will not be repeated. In this way, according to the configuration of the first modified example, since the plurality of first dispersion blades 52 and the plurality of second dispersion blades 62 have different lengths in the radial direction, the brown coals supplemented to the plurality of first dispersion blades 52 and the plurality of second dispersion blades 62 drop at different timings as it goes away from the plurality of first dispersion blades 52 and the plurality of second dispersion blades 62. That is, in the case of the dispersion blades 52 and 62 which are long in 27 the radial direction, the dropping timing is slower than that of the dispersion blades 52 and 62 which are short in the radial direction, so that the brown coal is input to the far position in the length direction of the drying chamber 12. On the other hand, in the case of the dispersion blades 52 and 62 which are short in the radial direction, the dropping timing is faster than that of the dispersion blades 52 and 62 which are long in the radial direction, so that the brown coal is input to the near position in the length direction of the drying chamber 12. Thus, the first fuel dispersion portion 43 and the second fuel dispersion portion 44 may input the brown coal so that the brown coal is dispersed in the length direction and the width direction while the rotary shafts 51 and 61 rotate by one revolution. Furthermore, all of the plurality of first dispersion blades 52 and the plurality of second dispersion blades 62 may not have different lengths in the radial direction, and at least one first dispersion blade 52 and at least one second dispersion blade 62 may have different lengths from the other first dispersion blade 52 and the other second dispersion blade 62. That is, the other first dispersion blade 52 and the other second dispersion blade 62 may have the same length in the radial direction. According to the configurations of the embodiments, since the rotation speed of the first rotary shaft may be changed at a predetermined cycle, the pulverized fuel may be dispersed in the length direction, for example, even when the front end side of the first dispersion blade is flat. That is, when the pulverized fuel is supplied toward the far position in the length direction, the rotation speed of the first rotary shaft is increased by the control device. On the other hand, when the pulverized fuel is supplied toward the near position in the length direction, 28 the rotation speed of the first rotary shaft is decreased by the control device. Then, since the rotation speed is changed between the high rotation speed and the low rotation speed at a predetermined cycle, the pulverized fuel may be supplied in a dispersion state from the far position to the near position in the length direction. According to the configurations of the embodiments, since the pulverized fuel may be dispersed in the length direction even while the first rotary shaft rotates by one revolution, the pulverized fuel may be further dispersed. According to the configurations of the embodiments, since the pulverized coal fuel supplied to the first fuel dispersion portion may be dispersed in the width direction by the second fuel dispersion portion, the pulverized coal fuel may be evenly supplied in the width direction of the first fuel dispersion portion. According to the configurations of the embodiments, since the pulverized coal fuel may be evenly supplied in the width direction of the first fuel dispersion portion by causing the pulverized fuel to pass through the dispersion container, the configuration may be simplified. According to the configurations of the embodiments, even when a space for installing the dispersion container may not be secured, the pulverized coal fuel may be evenly supplied in the width direction of the first fuel dispersion portion by the second fuel dispersion portion. According to the configurations of the embodiments, since the pulverized fuel may be dispersed in the width direction while the second rotary shaft rotates by one revolution, the pulverized fuel may be further dispersed. According to the configurations of the embodiments, since the rotation speeds of the first rotary shaft and the second rotary shaft may be set at a predetermined cycle 29 corresponding to the specific weight of the pulverized fuel, various kinds of pulverized fuels may be supplied in an appropriate dispersion state. Furthermore, the specific weight of the pulverized fuel changes by the type of pulverized fuel, a water content ratio, and the like. According to the configurations of the embodiments, the wet fuel which is appropriately dispersed and dried in the fluid bed drying apparatus may be supplied to the gasification furnace. According to the configurations of the embodiments, since the rotation speed of the first rotary shaft may be changed at a predetermined cycle, the pulverized fuel may be dispersed in the length direction, for example, even when the front end side of the first dispersion blade is flat. That is, when the pulverized fuel is supplied toward the far position in the length direction, the rotation speed of the first rotary shaft is increased by the control device. On the other hand, when the pulverized fuel is supplied toward the near position in the length direction, the rotation speed of the first rotary shaft is decreased by the control device. Then, since the rotation speed is changed between the high rotation speed and the low rotation speed at a predetermined cycle, the pulverized fuel may be supplied in a dispersion state from the far position to the near position in the length direction. According to the fluid bed drying apparatus, the gasification combined power generating facility, and the pulverized fuel supply method of the invention, it is possible to appropriately disperse the pulverized fuel.

Claims (12)

1. A fluid bed drying apparatus comprising: a drying container which has a rectangular inner space formed in a height direction along a vertical direction and length and width directions perpendicular to the height direction, and forms a fluid bed in the inner space by fluidizing a pulverized fuel input to the inner space through a fluidizing gas; a pulverized fuel input portion for inputting the pulverized fuel from one end side of the drying container in the length direction; a first fuel dispersion portion for dispersing the pulverized fuel input from the pulverized fuel input portion in the length direction of the inner space of the drying container; and a control device for controlling the first fuel dispersion portion, wherein the first fuel dispersion portion includes a first rotary shaft having an axial direction which corresponds to the width direction, a plurality of first dispersion blades provided at a predetermined interval'in a circumferential direction of the first rotary shaft, and a first driving device for rotating the first rotary shaft, wherein the control device is configured to control the first driving device so as to change a rotation speed of the first rotary shaft at a predetermined cycle.

2. The fluid bed drying apparatus according to claim 1, Wherein, in the plurality of first dispersion blades, at least one first dispersion blade and the other first 31 dispersion blade have different lengths in a radial direction of the first rotary shaft.

3. The fluid bed drying apparatus according to claim 1 or 2, wherein the length of the first fuel dispersion portion in the width direction is substantially the length of the inner space of the drying container in the width direction, and wherein the fluid bed drying apparatus further comprises a second fuel dispersion portion provided between the pulverized fuel input portion and the drying container, the second fuel dispersion portion being adapted to disperse the pulverized fuel input from the pulverized fuel input portion in the width direction of the inner space of the drying container to be supplied to the first fuel dispersion portion.

4. The fluid bed drying apparatus according to claim 3, wherein the second fuel dispersion portion includes a dispersion container which is widened in the width direction from the pulverized fuel input portion toward the drying container.

5. The fluid bed drying apparatus according to claim 3, wherein the second fuel dispersion portion includes a second rotary shaft having an axial direction which corresponds to the length direction, a plurality of second dispersion blades provided at a predetermined interval in the circumferential direction of the second rotary shaft, and a second driving device for rotating the second rotary shaft, and 32 wherein the control device is configured to control the second driving device so as to change the rotation speed of the second rotary shaft at a predetermined cycle.

6. The fluid bed drying apparatus according to claim 5, Wherein, in the plurality of second dispersion blades, at least one second dispersion blade and the other second dispersion blade have different lengths in the radial direction of the second rotary shaft.

7. The fluid bed drying apparatus according to any one of claims 1 to 6, wherein the control device is configured to change the predetermined cycle in response to the specific weight of the pulverized fuel.

8. A gasification combined power generating facility comprising: the fluid bed drying apparatus according to any one of claims 1 to 7; a gasification furnace for treating the dried wet fuel supplied from the fluid bed drying apparatus so that the fuel is changed into a gasified gas; a gas turbine which is operated by using the gasified gas as fuel; a steam turbine which is operated by steam produced by an exhausted heat recovery boiler into which a turbine flue gas is introduced from the gas turbine; and a generator which is connected to the gas turbine and the steam turbine.

9. A pulverized fuel supply method comprising: supplying a pulverized fuel into a drying container - 33 with a rectangular inner space formed in a height direction along a vertical direction and length and width directions perpendicular to the height direction, wherein the drying container is provided with a first fuel dispersion portion that includes a first rotary shaft of which the axial direction becomes the width direction, a plurality of first dispersion blades which are provided at a predetermined interval in a circumferential direction of the first rotary shaft, and a first driving device which rotates the first rotary shaft, and wherein the pulverized fuel supply method further comprising: inputting the pulverized fuel toward the first fuel dispersion portion while controlling the first driving device with the control device so as to change the rotation speed of the first rotary shaft at a predetermined cycle.

10. A fluid bed drying apparatus substantially as herein described with reference to any one of the embodiments of the invention illustrated in the accompanying examples and/or drawings.

11. A gasification combined power generating facility substantially as herein described with reference to any one of the embodiments of the invention illustrated in the accompanying examples and/or drawings.

12. A pulverized fuel supply method substantially as herein described with reference to any one of the embodiments of the invention illustrated in the accompanying examples and/or drawings.