AU2012243826B2

AU2012243826B2 - Fluidized bed drying apparatus

Info

Publication number: AU2012243826B2
Application number: AU2012243826A
Authority: AU
Inventors: Norihiro Fukuda; Masaaki Kinoshita; Keisuke Matsuo; Hiroyuki NAKAHARAI; Koji Ohura; Katsuhiko Yokohama
Original assignee: Mitsubishi Heavy Industries Ltd
Current assignee: Mitsubishi Heavy Industries Ltd
Priority date: 2011-04-14
Filing date: 2012-04-11
Publication date: 2015-03-26
Anticipated expiration: 2032-04-11
Also published as: JP2012225518A; AU2012243826A1; WO2012141217A1

Abstract

A fluidized bed drying apparatus (1) capable of drying brown coal while a fluidized bed (3) is formed by fluidizing the brown coal with fluidization gas is provided with: a drying furnace (5); and a gas dispersion board (6) dividing the inside of the drying furnace (5) into a chamber room (11) into which the fluidization gas flows and a drying room (12) into which the brown coal is supplied, and causing the fluidization gas to flow from the chamber room (11) into the drying room (12). A plurality of the chamber rooms (11) is disposed along the direction of fluidization of the brown coal. Into a first chamber room (18) positioned upstream of the direction of fluidization, a first fluidization gas with a low vapor concentration flows. Into a second chamber room (19) positioned downstream of the direction of fluidization, a second fluidization gas with a relatively high vapor concentration compared to the first fluidization gas flows.

Description

1 DESCRIPTION FLUIDIZED BED DRYING APPARATUS Field [0001] The present invention relates to a fluidized bed 5 drying apparatus that dries a wet fuel such as brown coal while causing the wet fuel to flow. Background [0002] Heretofore, an apparatus including a drying furnace (main body), a partition plate that partitions the 10 inside of the drying furnace into a feed chamber and a dry classification chamber, and chamber rooms (wind box) provided on lower portions of the feed chamber and the dry classification chamber, respectively with a gas dispersion board interposed therebetween is known as the fluidized bed 15 drying apparatus (for example, see Patent Literature 1). In the fluidized bed drying apparatus, agglomeration of a wet fuel supplied into the drying furnace is suppressed, and a flow within the drying furnace is stabilized by adjusting a flow rate of fluidization gas supplied to the 20 feed chamber and the dry classification chamber. Citation List Patent Literature [0003] Patent Literature 1: Japanese Patent Application Laid-open No. 2008-128524 25 [0003a] Any discussion of the prior art throughout the specification should in no way be considered as an admission that such prior art is widely known or forms part of common general knowledge in the field. Summary 30 Technical Problem [0004] Incidentally, the fluidization gas used in the fluidized bed drying apparatus is heated to dry a wet fuel. In this case, condensable gas such as steam may be used as 2 the fluidization gas to efficiently recover latent heat of the fluidization gas (exhaust gas) discharged after the dry. When steam is used as the fluidization gas, a wet fuel may be suitably dried by adjusting a flow rate of the 5 fluidization gas as in the conventional fluidized bed drying apparatus. However, fluidization gas such as steam is needed to have a high temperature as compared to non condensable gas so as to suppress condensation within a pipe or a drying furnace. For this reason, it is difficult 10 to achieve further stable operation or efficiency of the fluidized bed drying apparatus only using condensable gas. [0005] Therefore, an object of the invention is to provide a fluidized bed drying apparatus capable of achieving efficient dry of a wet fuel, suppressing a poor 15 flow of a wet fuel, and suitably drying a wet fuel. [0005a] It is an object of the present invention to overcome or ameliorate at least one of the disadvantages of the prior art, or to provide a useful alternative. [0005b] Unless the context clearly requires otherwise, 20 throughout the description and the claims, the words "comprise", "comprising", and the like are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense; that is to say, in the sense of "including, but not limited to". 25 Solution to Problem [0006] According to a aspect of the present invention, there is provided a fluidized bed drying apparatus for drying a wet fuel while a fluidized bed is formed by causing the wet fuel to flow using fluidization gas, 30 including: a drying furnace; and a gas blowing unit for dividing an inside of the drying furnace into a chamber room into which the fluidization gas flows and a drying room into which the wet fuel is supplied, and for causing 2a the fluidization gas to flow from the chamber room into the drying room, wherein a plurality of chamber rooms are disposed along a flow direction of the wet fuel, a first fluidization gas having a low vapor concentration flows 5 into the chamber room positioned on an upstream side of the flow direction, and a second fluidization gas having a relatively high vapor concentration compared to the first fluidization gas flows into the chamber room positioned on a downstream side of the flow direction. 10 [0007] According to this configuration, it is possible to dry a wet fuel on an upstream side of the flow direction corresponding to an initial stage of dry by using a first fluidization gas having a low vapor concentration, and it Docket No. PMHA-13014-AU 3 is possible to dry a wet fuel on a downstream side of the flow direction corresponding to a late stage by using the second fluidization gas having a high vapor concentration. In this way, since a wet fuel may be suitably dried while 5 retaining a low temperature of the first fluidization gas compared to the second fluidization gas as much as a low vapor concentration of the first fluidization, the wet fuel can be dried efficiently and suitably. A board having multiple through-holes (gas dispersion board), or a board 10 having multiple gas nozzles may be applied as a gas blowing unit. [0008] In this case, it is preferable that the fluidized bed drying apparatus further includes: a heat transfer tube which is provided in the drying room, and in which a 15 heating medium circulating through the inside flows from a downstream side toward an upstream side of the flow direction; a gas outlet which discharges exhaust gas generated in the drying room; a first heating medium supply line which connects the gas outlet to an inflow side of the 20 heat transfer tube; and a compressor which is provided on the first heating medium supply line, and is capable of supplying the exhaust gas as the heating medium of the heat transfer tube by compressing the exhaust gas. [0009] According to this configuration, since exhaust 25 gas discharged from the drying room through the gas outlet may be used as a heating medium of the heat transfer tube, the wet fuel can be further dried efficiently as much as latent heat of the exhaust gas that may be effectively used. [0010] In this case, it is preferable that the fluidized 30 bed drying apparatus further includes: a first fluidization gas supply line which connects an outflow side of the heat transfer tube to the chamber room positioned on the upstream side of the flow direction; and a second Docket No. PMHA-13014-AU 4 fluidization gas supply line which connects the first heating medium supply line to the chamber room positioned on the downstream side of the flow direction. [0011] According to this configuration, since a heating 5 medium of the heat transfer tube may be used as the first fluidization gas, the wet fuel can be further dried efficiently as much as the heating medium that may be effectively used. In addition, since exhaust gas flowing through the first heating medium supply line may be used as 10 the second fluidization gas, the wet fuel can be further dried efficiently as much as latent heat of the exhaust gas that may be effectively used. [0012] In this case, it is preferable that the fluidized bed drying apparatus, further includes a first gas-liquid 15 separator which is provided on the first fluidization gas supply line, and is capable of separating condensate contained in the heating medium which is discharged from the heat transfer tube. [0013] According to this configuration, it is possible 20 to separate a condensate contained in a heating medium which is discharged from the heat transfer tube using the first gas-liquid separator, and suitably use the heating medium from which the condensate is separated as the first fluidization gas. In this way, the first fluidization gas 25 has a low vapor concentration after the condensate is separated, and thus may be suitably used as the first fluidization gas. [0014] In this case, it is preferable that the fluidized bed drying apparatus further includes a first partition 30 member which divides the drying room into a plurality of drying rooms corresponding to the plurality of chamber rooms, wherein the heat transfer tube is provided in each of the plurality of drying rooms.

Docket No. PMHA-13014-AU 5 [0015] According to this configuration, it is possible to dry a wet fuel in a drying room into which the first fluidization gas flows, and then dry the wet fuel in a 5 drying room into which the second fluidization gas flows. For this reason, it is possible to inhibit a wet fuel on an upstream side of the flow direction from moving to a downstream side of the flow direction in a non-dry state, and suitably dry the wet fuel. 10 [0016] In this case, it is preferable that the fluidized bed drying apparatus further includes; a temperature detection sensor provided in the plurality of drying rooms; a flow rate adjusting valve capable of adjusting a flow rate of the second fluidization gas; and a control device 15 which controls the flow rate adjusting valve based on a detected temperature of the temperature detection sensor, wherein the control device controls the flow rate adjusting valve so that a temperature of the drying room positioned on a downstream side of the flow direction is high when 20 compared to the drying room positioned on an upstream side of the flow direction. [0017] According to this configuration, it is possible to increase a temperature of the drying room positioned on a downstream side of the flow direction as compared to the 25 drying room positioned on an upstream side of the flow direction by controlling the flow rate adjusting valve based on a detected temperature of the temperature detection sensor. In this way, since latent heat of exhaust gas may be appropriately distributed as each 30 fluidization gas, it is possible to efficiently use the latent heat of exhaust gas. [0018] In this case, it is preferable that the plurality of heat transfer tubes provided in the plurality of chamber Docket No. PMHA-13014-AU 6 rooms are connected to one another so that the heating medium flows from the heat transfer tube positioned on a downstream side of the flow direction toward the heat transfer tube positioned on an upstream side of the flow 5 direction. [0019] According to this configuration, it is possible to increase a temperature of the heat transfer tube from an upstream side toward a downstream side of the flow direction. In this way, it is possible to suitably dry a 10 wet fuel without condensing steam contained in the first fluidization gas and the second fluidization gas. [0020] In this case, it is preferable that the fluidized bed drying apparatus further includes: a second gas-liquid separator which is provided in a connecting part of the 15 heat transfer tube positioned on a downstream side of the flow direction and the heat transfer tube positioned on an upstream side of the flow direction, and is capable of separating condensate contained in the heating medium; a heater capable of heating the first fluidization gas; and a 20 second heating medium supply line which introduces the condensate separated in the second gas-liquid separator into the heater as a heating medium of the heater. [0021] According to this configuration, since a condensate in a heating medium separated by the second gas 25 liquid separator in the connecting part of the heat transfer tube may be used as a heating medium of the heater that heats the first fluidization gas, the wet fuel can be further dried efficiently as much as the condensate that may be effectively used. 30 [0022] In this case, it is preferable that the fluidized bed drying apparatus further includes an air bleed line which bleeds the exhaust gas from the first heating medium supply line, wherein the first heating medium supply line Docket No. PMHA-13014-AU 7 connects the gas outlet to an inflow side of the heat transfer tube positioned on the downstream side, the air bleed line connects the first heating medium supply line to an inflow side of the heat transfer tube positioned on the 5 upstream side, and the compressor is provided on the first heating medium supply line positioned on a downstream side of a connecting part where the first heating medium supply line is connected to the air bleed line. [0023] According to this configuration, since a flow 10 rate of exhaust gas supplied to the compressor may be reduced as much as exhaust gas, which flows through the first heating medium supply line, bled through the air bleed line, it is possible to reduce power of the compressor, and enhance operating efficiency. 15 [0024] In this case, it is preferable that the fluidized bed drying apparatus further includes a second partition member which is provided in the drying furnace, and divides a freeboard positioned on an upper portion of the fluidized bed formed in the plurality of drying rooms into a 20 plurality of freeboards corresponding to the plurality of drying rooms. [0025] In this configuration, it is possible to inhibit exhaust gas from condensing by mixing exhaust gas discharged from a drying room positioned on an upstream 25 side of the flow direction with exhaust gas discharged from a drying room positioned on a downstream side of the flow direction. Advantageous Effects of Invention [0026] According to a fluidized bed drying apparatus of 30 the invention, when a wet fuel on an upstream side of a flow direction is dried using a first fluidization gas having a low vapor concentration, and a wet fuel on a downstream side of the flow direction is dried using a Docket No. PMHA-13014-AU 8 second fluidization gas having a high vapor concentration, it is possible to decrease a temperature of the first fluidization gas, and suitably dry a wet fuel, and thus the wet fuel can be dried efficiently and suitably. 5 Brief Description of Drawings [0027] FIG. 1 is a schematic configuration diagram of an integrated coal gasification combined cycle to which a fluidized bed drying apparatus according to a first embodiment is applied. 10 FIG. 2 is a schematic configuration diagram schematically illustrating the fluidized bed drying apparatus according to the first embodiment. FIG. 3 is a schematic configuration diagram schematically illustrating a fluidized bed drying apparatus 15 according to a second embodiment. FIG. 4 is a schematic configuration diagram schematically illustrating a fluidized bed drying apparatus according to a third embodiment. FIG. 5 is a graph illustrating an enthalpy-temperature 20 curve of a heating medium flowing through a heat transfer tube, and an enthalpy-temperature curve of brown coal that is being dried in the fluidized bed drying apparatus according to the third embodiment. FIG. 6 is a schematic configuration diagram 25 schematically illustrating the fluidized bed drying apparatus according to a fourth embodiment. FIG. 7 is a graph illustrating an enthalpy-temperature curve of a heating medium flowing through a heat transfer tube, and an enthalpy-temperature curve of brown coal that 30 is being dried in the fluidized bed drying apparatus according to the fourth embodiment. Description of Embodiments [0028] Hereinafter, a fluidized bed drying apparatus Docket No. PMHA-13014-AU 9 according to the invention will be described with reference to accompanying drawings. The invention is not limited to Examples below. In addition, a component in the Examples below includes a component that may be and is easily 5 substituted by those skilled in the art, or the substantially same component. First Embodiment [0029] FIG. 1 is a schematic configuration diagram of an integrated coal gasification combined cycle power 10 generation facility to which a fluidized bed drying apparatus according to a first embodiment is applied. An IGCC (Integrated Coal Gasification Combined Cycle) 100 to which a fluidized bed drying apparatus 1 according to the first embodiment is applied employs an air combustion 15 scheme that generates coal gas in a gasifier using air as an oxidant, and supplies coal gas purified in a gas purifier to a gas turbine facility as exhaust gas to generate electricity. That is, the IGCC 100 of the first embodiment is a power facility of the air combustion scheme 20 (air blown). In this case, brown coal is used as a wet raw material supplied to the gasifier. [0030] In the first embodiment, brown coal is used as a wet raw material. However, low-grade coal containing subbituminous coal and the like, or peat such as sludge may 25 be applied as long as moisture content is high. In addition, high-grade coal may be applied. In addition, a wet raw material is not limited to coal such as brown coal, and may be biomass which is used as a regenerable organism derived organic resource. For example, it is possible to 30 use a thinned wood, an abolished wood, a driftwood, grass, waste, grime, a tire, a recycled fuel having a decreased quantity thereof (pellet or chip), and the like. [0031] In the first embodiment, as illustrated in FIG. 1, Docket No. PMHA-13014-AU 10 the IGCC 100 includes a coaling equipment 111, the fluidized bed drying apparatus 1, a coal pulverizer 113, a coal gasifier 114, a char recovery device 115, a gas purifier 116, a gas turbine facility 117, a steam turbine 5 facility 118, a generator 119, and an HRSG (Heat Recovery Steam Generator) 120. [0032] The coaling equipment 111 includes a raw coal bunker 121, a coal feeder 122, and a crusher 123. The raw coal bunker 121 may store brown coal, and drops a 10 predetermined amount of brown coal into the coal feeder 122. The coal feeder 122 conveys the brown coal dropped from the raw coal bunker 121 by a conveyor and the like, and drops the brown coal into the crusher 123. The crusher 123 finely crushes the dropped brown coal to refine grains. 15 [0033] As will be described in detail, the fluidized bed drying apparatus 1 causes the brown coal dropped from the coaling equipment 111 to flow using fluidization gas, and heats and dries the brown coal by a heat transfer tube 33, thereby removing moisture contained in the brown coal. A 20 cooler 131 that cools down brown coal (dried coal) of a discharged drying agent is connected to the fluidized bed drying apparatus 1. A dried coal bunker 132 that stores dried coal of a cooling agent is connected to the cooler 131. In addition, a dried coal cyclone 133 and a dried 25 coal electrical dust collector 134 are connected to the fluidized bed drying apparatus 1 as a dust collector 139 that separates particles of dried coal from exhaust gas discharged to the outside. The particles of dried coal separated from exhaust gas in the dried coal cyclone 133 30 and the dried coal electrical dust collector 134 are stored in the dried coal bunker 132. The exhaust gas from which dried coal is separated in the dried coal electrical dust collector 134 is compressed in a steam compressor Docket No. PMHA-13014-AU 11 (compressor) 135, and then is supplied as a heating medium to the heat transfer tube 33 of the fluidized bed drying apparatus 1. [0034] The coal pulverizer 113 pulverizes brown coal 5 (dried coal) dried by the fluidized bed drying apparatus 1 into a shape of minute particles to manufacture pulverized coal. That is, when dried coal stored in the dried coal bunker 132 is dropped by a coal feeder 136, the coal pulverizer 113 changes the dried coal to pulverized coal 10 having a predetermined particle diameter or less. Then, the pulverized coal which is pulverized in the coal pulverizer 113 is separated from gas for conveying by pulverized coal bag filters 137a and 137b, and is stored in pulverized coal supply hoppers 138a and 138b. 15 [0035] The coal gasifier 114 is supplied with pulverized coal processed in the coal pulverizer 113, and is supplied with char (unburnt combustible content of coal) recovered in the char recovery device 115. [0036] The coal gasifier 114 is connected to a 20 compressed air supply line 141 from the gas turbine facility 117 (a compressor 161), and may be supplied with compressed air which is compressed in the gas turbine facility 117. An air separation plant 142 separately generates nitrogen and oxygen from air in the atmosphere. 25 A first nitrogen supply line 143 is connected to the coal gasifier 114, and coaling lines 144a and 144b extending from the pulverized coal supply hoppers 138a and 138b are connected to the first nitrogen supply line 143. In addition, a second nitrogen supply line 145 is connected to 30 the coal gasifier 114, and a char return line 146 extending from the char recovery device 115 is connected to the second nitrogen supply line 145. Further, an oxygen supply line 147 is connected to the compressed air supply line 141.

Docket No. PMHA-13014-AU 12 In this instance, nitrogen is used as gas for conveying coal or char, and oxygen is used as an oxidation agent. [0037] For example, the coal gasifier 114 is an entrained-bed type gasifier which combusts and gasifies 5 steam used as a gasifying agent, or coal, char, and air (oxygen) supplied inside, and generates combustible gas (produced gas and coal gas) mainly containing carbon dioxide, and thus a gasification reaction occurs using the combustible gas as a gasifying agent. The coal gasifier 10 114 is provided with a foreign substance removal device 148 that removes a mixed foreign substance of pulverized coal. In this case, the coal gasifier 114 is not limited to the entrained-bed gasifier, and a fluid-bed gasifier or a fixed-bed gasifier may be used. The coal gasifier 114 is 15 provided with a gas production line 149 of combustible gas toward the char recovery device 115, so that combustible gas containing char may be discharged. In this case, when the gas production line 149 is provided with a gas cooler, combustible gas may be supplied to the char recovery device 20 115 after being cooled down up to a predetermined temperature. [0038] The char recovery device 115 includes a dust collector 151 and a supply hopper 152. In this case, each dust collector 151 includes a bag filter or a plurality of 25 bag filters, and a cyclone or a plurality of cyclones, and may separate char contained in combustible gas which is generated in the coal gasifier 114. Then, the combustible gas from which the char is separated is sent to the gas purifier 116 through a gas discharge line 153. The supply 30 hopper 152 stores the char which is separated from the combustible gas by the dust collector 151. A bin may be disposed between the dust collector 151 and the supply hopper 152, and a plurality of supply hoppers 152 may be Docket No. PMHA-13014-AU 13 connected to the bin. The char return line 146 extending from the supply hopper 152 is connected to the second nitrogen supply line 145. [0039] The gas purifier 116 purifies gas by removing 5 impurities such as sulfur compound and nitrogen compound for combustible gas from which char is separated by the char recovery device 115. The gas purifier 116 manufactures fuel gas by purifying combustible gas, and supplies the fuel gas to the gas turbine facility 117. 10 Sulfur content (H 2 S) is contained in combustible gas from which char is separated in the gas purifier 116, and thus sulfur content is finally recovered as gypsum and is effectively used by removing sulfur content by an amine absorbing liquid. 15 [0040] The gas turbine facility 117 includes the compressor 161, a combustor 162, and a turbine 163. The compressor 161 and the turbine 163 are connected to each other by a rotating shaft 164. The combustor 162 is connected to a compressed air supply line 165 from the 20 compressor 161, and is connected to a fuel gas supply line 166 from the gas purifier 116, and a fuel gas supply line 167 is connected to the turbine 163. In addition, the gas turbine facility 117 is provided with the compressed air supply line 141 extending from the compressor 161 to the 25 coal gasifier 114, and a booster 168 is provided on the compressed air supply line 141. Thus, it is possible to mix and combust compressed air supplied from the compressor 161 and fuel gas supplied from the gas purifier 116 in the combustor 162, and to drive the generator 119 by rotating 30 the rotating shaft 164 by generated combustible gas in the turbine 163. [0041] The steam turbine facility 118 includes a turbine 169 connected to the rotating shaft 164 in the gas turbine Docket No. PMHA-13014-AU 14 facility 117, and the generator 119 is connected to a proximal end of the rotating shaft 164. The HRSG 120 is provided on a flue gas line 170 extending from the gas turbine facility 117 (turbine 163), and generates steam by 5 exchanging heat between air and high-temperature flue gas. For this reason, the HRSG 120 is provided with a steam supply line 171 between the HRSG 120 and the turbine 169 of the steam turbine facility 118. Further, a steam recovery line 172 is provided, and a condenser 173 is provided on 10 the steam recovery line 172. Thus, in the steam turbine facility 118, the turbine 169 is driven by steam supplied from the HRSG 120, and the generator 119 may be driven by rotating the rotating shaft 164. [0042] Then, a harmful substance is removed from flue 15 gas, of which heat is recovered in the HRSG 120, by a gas purification unit 174, and the cleaned flue gas is released into the atmosphere from a stack 175. [0043] Herein, an operation of the IGCC 100 of the first embodiment will be described. 20 [0044] In the IGCC 100 of the first embodiment, raw coal (brown coal) is stored in the raw coal bunker 121 by the coaling equipment 111, and the brown coal of the raw coal bunker 121 is dropped into the crusher 123 by the coal feeder 122, and is crushed in a predetermined size therein. 25 Then, the crushed brown coal is heated and dried by the fluidized bed drying apparatus 1, and then is cooled down by the cooler 131, and is stored in the dried coal bunker 132. In addition, particles of dried coal are separated from exhaust gas, which is discharged from the fluidized 30 bed drying apparatus 1, by the dried coal cyclone 133 and the dried coal electrical dust collector 134, and the exhaust gas is compressed in the steam compressor 135, and then is returned as a heating medium to the heat transfer Docket No. PMHA-13014-AU 15 tube 33 of the fluidized bed drying apparatus 1. On the other hand, particles of dried coal separated from steam are stored in the dried coal bunker 132. [0045] The dried coal stored in the dried coal bunker 5 132 is introduced into the coal pulverizer 113 by the coal feeder 136, and is pulverized in a shape of minute particles to manufacture pulverized coal in the coal pulverizer 113. The manufactured pulverized coal is stored in the pulverized coal supply hoppers 138a and 138b through 10 the pulverized coal bag filters 137a and 137b. The pulverized coal stored in the pulverized coal supply hoppers 138a and 138b is supplied to the coal gasifier 114 through the first nitrogen supply line 143 by nitrogen supplied from the air separation plant 142. In addition, 15 char recovered in the char recovery device 115 described below is supplied to the coal gasifier 114 through the second nitrogen supply line 145 by nitrogen supplied from the air separation plant 142. Further, a pressure of compressed air bled from the gas turbine facility 117 20 described below is increased in the booster 168, and then the compressed air is supplied to the coal gasifier 114 through the compressed air supply line 141 together with oxygen supplied from the air separation plant 142. [0046] When pulverized coal and char supplied are 25 combusted by compressed air (oxygen), and the pulverized coal and the char are gasified in the coal gasifier 114, it is possible to generate combustible gas (coal gas) mainly containing carbon dioxide. Then, the combustible gas is discharged from the coal gasifier 114 through the gas 30 production line 149, and is sent to the char recovery device 115. [0047] In the char recovery device 115, the combustible gas is first supplied to the dust collector 151, and the Docket No. PMHA-13014-AU 16 dust collector 151 separates char contained in the combustible gas. Then, the combustible gas from which char is separated is sent to the gas purifier 116 through the gas discharge line 153. On the other hand, the finer 5 grained char separated from the combustible gas is deposited in the supply hopper 152, and is returned to the coal gasifier 114 through the char return line 146 so as to be recycled. [0048] Combustible gas, from which char is separated by 10 the char recovery device 115, is purified by removing impurities such as sulfur compound and nitrogen compound in the gas purifier 116, and fuel gas is manufactured. In the gas turbine facility 117, in response to the compressor 161 generating compressed air and supplying the compressed air 15 to the combustor 162, the combustor 162 mixes and combusts the compressed air supplied from the compressor 161 and fuel gas supplied from the gas purifier 116, thereby generating combustion gas. When the turbine 163 is driven by the combustion gas, the generator 119 is driven through 20 the rotating shaft 164, and electricity may be generated. [0049] Steam is generated when heat is exchanged in the HRSG 120 between air and fuel gas discharged from the turbine 163 of the gas turbine facility 117, and the generated steam is supplied to the steam turbine facility 25 118. In the steam turbine facility 118, when the turbine 169 is driven by steam supplied from the HRSG 120, the generator 119 may be driven through the rotating shaft 164, thereby generating electricity. [0050] Thereafter, in the gas purification unit 174, a 30 harmful substance of exhaust gas discharged from the HRSG 120 is removed, and purified flue gas is released to the atmosphere from the stack 175. [0051] Hereinafter, the fluidized bed drying apparatus 1 Docket No. PMHA-13014-AU 17 in the IGCC 100 described above will be described in detail. FIG. 2 is a schematic configuration diagram schematically illustrating the fluidized bed drying apparatus according to the first embodiment. The fluidized bed drying 5 apparatus 1 of the first embodiment heats and dries brown coal put by the coaling equipment 111 while causing the brown coal to flow by fluidization gas. [0052] The fluidized bed drying apparatus 1 includes a drying furnace 5 supplied with brown coal therein, and a 10 gas dispersion board (gas blowing unit) 6 provided on the inside of the drying furnace 5. The drying furnace 5 is formed in a shape of a box of a parallelepiped. The gas dispersion board 6 divides a space in the drying furnace 5 into a chamber room 11 (wind room) positioned on a lower 15 side in a vertical direction (lower side of the drawing), and a drying room 12 positioned on an upper side in the vertical direction (upper side of the drawing). Multiple through-holes are formed in the gas dispersion board 6, fluidization gas such as steam and nitrogen is introduced 20 into the chamber room 11, and brown coal is supplied to the drying room 12. An upper portion of the drying room 12 is provided with a gas outlet 13 that discharges exhaust gas generated on the inside. The gas dispersion board 6 is used in the first embodiment. However, the invention is 25 not limited to this configuration, and a board including multiple gas nozzles may be applied. [0053] Thus, when brown coal supplied to the drying room 12 flows by fluidization gas flowing in through the gas dispersion board 6 from the chamber room 11, a fluidized 30 bed 3 is formed on the inside of the drying room 12, and a freeboard F is formed on an upper portion of the fluidized bed 3. Then, brown coal forming the fluidized bed 3 flows along a flow direction from an end portion (left side of Docket No. PMHA-13014-AU 18 the drawing) toward the other end portion (right side of the drawing) of the drying furnace 5. The fluidization gas flowing into the drying room 12 changes to exhaust gas, and is discharged from the gas outlet 13 together with steam 5 generated when brown coal is dried. The gas outlet 13 is connected to the dust collector 139 including the dried coal cyclone 133 and the dried coal electrical dust collector 134 described above. [0054] The fluidized bed drying apparatus 1 includes a 10 chamber partition plate 14 that divides the chamber room 11, a lower partition plate (first partition member) 15 that divides the fluidized bed 3 of the drying room 12, and an upper partition plate (second partition member) 16 that divides the freeboard F of the drying room 12. 15 [0055] The chamber partition plate 14 divides the chamber room 11 into a plurality of rooms along a flow direction. Specifically, the chamber partition plate 14 divides the chamber room 11 into a first chamber room 18 positioned on an upstream side of the flow direction, and a 20 second chamber room 19 positioned on a downstream side of the first chamber room 18. The first fluidization gas flows into the first chamber room 18, and the second fluidization gas flows into the second chamber room 19. The first fluidization gas and the second fluidization gas 25 are generated by mixing condensable gas with non condensable gas. Examples of condensable gas include steam, and examples of non-condensable gas include air and nitrogen. [0056] The first fluidization gas flowing into the first 30 chamber room 18 has a low vapor concentration, and the second fluidization gas flowing into the second chamber room 19 has a high vapor concentration. That is, the first fluidization gas has a lower vapor concentration when Docket No. PMHA-13014-AU 19 compared to the second fluidization gas. In other words, the second fluidization gas has a higher vapor concentration when compared to the first fluidization gas. In addition, a temperature of the first fluidization gas is 5 lower than that of the second fluidization gas. [0057] A lower end portion of the lower partition plate 15 is connected to the gas dispersion board 6 corresponding to a bottom of the drying room 12, and an upper end portion thereof is positioned on an upper side of the fluidized bed 10 3 formed in the drying room 12. The upper partition plate 16 is made of an adiabatic material and the like. A lower end portion thereof is positioned on an upper side of the upper end portion of the lower partition plate 15, and an upper end portion thereof is positioned near the gas outlet 15 13. [0058] The drying room 12 is divided into a first drying room 21 and a second drying room 22 by the lower partition plate 15 and the upper partition plate 16. For this reason, brown coal forming the fluidized bed 3 of the first drying 20 room 21 flows into the second drying room 22 when the lower partition plate 15 overflows. In addition, exhaust gas generated in the first drying room 21 moves toward a freeboard F of the first drying room 21, and exhaust gas generated in the second drying room 22 moves toward a 25 freeboard F of the second drying room 22. For this reason, the upper partition plate 16 inhibits the exhaust gas in the freeboard F of the first drying room 21 and the exhaust gas in the freeboard F of the second drying room 22 from mixing together. 30 [0059] A brown coal supply port 31 supplying brown coal is connected to the first drying room 21, a brown coal discharge port 41 is connected to the second drying room 22, and the heat transfer tube 33 heating brown coal is Docket No. PMHA-13014-AU 20 provided in the first drying room 21 and the second drying room 22, respectively. [0060] The brown coal supply port 31 is connected to the first drying room 21 on an upstream side of a flow 5 direction of brown coal, and serves as a feed opening used to supply brown coal before drying to the first drying room 21. The crusher 123 described above is connected to the brown coal supply port 31, and fine-particled brown coal is supplied to the first drying room 21. 10 [0061] The brown coal discharge port 41 is connected to the second drying room 22 on a downstream side of a flow direction of brown coal, and serves as an outlet used to discharge brown coal after drying from the second drying room 22. The cooler 131 described above is connected to 15 the brown coal discharge port 41, and dried brown coal is discharged as dried coal. [0062] A heating medium circulates on the inside of the heat transfer tube 33, and the heating medium flows from a downstream side toward an upstream side of a flow direction. 20 The heat transfer tube 33 includes an upstream side heat transfer tube 33a provided on the inside of the fluidized bed 3 of the first drying room 21, and a downstream side heat transfer tube 33b provided on the inside of the fluidized bed 3 of the second drying room 22. 25 [0063] An inflow side of the downstream side heat transfer tube 33b is connected to the gas outlet 13 through a first heating medium supply line 51, and an outflow side thereof is connected to an inflow side of the upstream side heat transfer tube 33a. The first heating medium supply 30 line 51 supplies exhaust gas moving from the gas outlet 13 toward the downstream side heat transfer tube 33b as a heating medium. The dust collector 139 described above is provided on the first heating medium supply line 51, and Docket No. PMHA-13014-AU 21 the steam compressor 135 described above is provided on a downstream side of the dust collector 139. As such, particles of dried coal are separated from exhaust gas, which is discharged from the gas outlet 13, by the dust 5 collector 139, and the exhaust gas from which dried coal is separated is compressed by the steam compressor 135. The compressed exhaust gas has an increased temperature, and changes to a heating medium to flow into the downstream side heat transfer tube 33b. In this way, in response to 10 the heating medium flowing into the downstream side heat transfer tube 33b heats brown coal forming the fluidized bed 3 in the second drying room 22, and evaporates moisture contained in the brown coal. [0064] A second fluidization gas supply line 52 is 15 connected to the first heating medium supply line 51. An end portion of the second fluidization gas supply line 52 is connected to the first heating medium supply line 51, and the other end portion thereof is connected to the second chamber room 19. The second fluidization gas supply 20 line 52 supplies exhaust gas compressed by the steam compressor 135 to the second chamber room 19 as the second fluidization gas. A first flow rate adjusting valve 53 is provided on the second fluidization gas supply line 52, and the first flow rate adjusting valve 53 adjusts a flow rate 25 of the second fluidization gas flowing into the second chamber room 19. [0065] The inflow side of the upstream side heat transfer tube 33a is connected to the downstream side heat transfer tube 33b, and the outflow side thereof is 30 connected to a first fluidization gas supply line 55 described below. In this way, when a heating medium supplied from the downstream side heat transfer tube 33b flows into the upstream side heat transfer tube 33a, the Docket No. PMHA-13014-AU 22 upstream side heat transfer tube 33a heats brown coal forming the fluidized bed 3 in the first drying room 21, and evaporates moisture contained in the brown coal. In this instance, since a heating medium flowing through the 5 downstream side heat transfer tube 33b exchanges heat in the second drying room 22, a temperature of a heating medium flowing through the upstream side heat transfer tube 33a is lower than a temperature of a heating medium flowing through the downstream side heat transfer tube 33b. 10 [0066] Herein, a second gas-liquid separator 56 is provided in a connecting part of the upstream side heat transfer tube 33a and the downstream side heat transfer tube 33b. The second gas-liquid separator 56 separates condensate water (condensate) contained in a heating medium 15 discharged from the downstream side heat transfer tube 33b. The second gas-liquid separator 56 supplies condensate water separated from a heating medium to a second heating medium supply line 61 provided with a second flow rate adjusting valve 54. On the other hand, the second gas 20 liquid separator 56 supplies a heating medium, from which condensate water is separated, to the upstream side heat transfer tube 33a. [0067] An end portion of the first fluidization gas supply line 55 described above is connected to the upstream 25 side heat transfer tube 33a, and the other end portion thereof is connected to the first chamber room 18. For this reason, the first fluidization gas supply line 55 supplies a heating medium moving from the upstream side heat transfer tube 33a toward the second chamber room 19 as 30 the first fluidization gas. The first fluidization gas supply line 55 is provided with a first gas-liquid separator 57, and a downstream side of the first gas-liquid separator 57 is provided with a heater 58.

Docket No. PMHA-13014-AU 23 [0068] The first gas-liquid separator 57 separates condensate water (condensate) contained in a heating medium discharged from the upstream side heat transfer tube 33a. The first gas-liquid separator 57 discharges condensate 5 water separated from a heating medium from a condensate water discharge line 60 provided with a pressure reducing valve 59. On the other hand, the first gas-liquid separator 57 supplies a heating medium, from which condensate water is separated, to the first chamber room 18 10 through the first fluidization gas supply line 55. [0069] The heater 58 heats the first fluidization gas passing through the first gas-liquid separator 57, and uses condensate water separated from the second gas-liquid separator 56 as a heating medium that heats the first 15 fluidization gas. In this way, the heater 58 heats the first fluidization gas by exchanging heat between the first fluidization gas that flows in and condensate water separated from the second gas-liquid separator 56. [0070] In this way, a heating medium discharged from the 20 upstream side heat transfer tube 33a flows into the first gas-liquid separator 57 through the first fluidization gas supply line 55. A heating medium flowing into the first gas-liquid separator 57 flows into the heater 58 as the first fluidization gas after condensate water is separated. 25 The first fluidization gas flowing into the heater 58 is heated, and then flows into the first chamber room 18. For this reason, the first fluidization gas flowing into the first chamber room 18 has a low vapor concentration when compared to the second fluidization gas as much as 30 condensate water separated in the first gas-liquid separator 57 and the second gas-liquid separator 56. [0071] Next, a flow of a heating medium of the heat transfer tube 33 and exhaust gas in the fluidized bed Docket No. PMHA-13014-AU 24 drying apparatus 1 of the first embodiment will be described. The first fluidization gas flowing into the first drying room 21 changes to exhaust gas together with steam generated in the first drying room 21, and moves 5 toward the gas outlet 13. In addition, the second fluidization gas flowing into the second drying room 22 changes to exhaust gas together with steam generated in the second drying room 22, and moves toward the gas outlet 13. [0072] Exhaust gas flowing in from the gas outlet 13 10 passes through the dust collector 139 and the steam compressor 135 by way of the first heating medium supply line 51. A portion of exhaust gas passing through the steam compressor 135 changes to a heating medium, and flows into the downstream side heat transfer tube 33b by way of 15 the first heating medium supply line 51. On the other hand, a portion of exhaust gas passing through the steam compressor 135 changes to the second fluidization gas, and flows into the second chamber room 19 by way of the second fluidization gas supply line 52. The second fluidization 20 gas flowing into the second chamber room 19 is supplied to the second drying room 22, and then changes to exhaust gas again, and is discharged from the gas outlet 13. [0073] A heating medium flowing into the downstream side heat transfer tube 33b flows into the second gas-liquid 25 separator 56 after heat is exchanged between the heating medium and brown coal in the second drying room 22. Condensate water contained in a heating medium flowing into the second gas-liquid separator 56 is separated from the heating medium. The separated condensate water flows into 30 the heater 58 by way of the second heating medium supply line 61, and the heating medium, from which the condensate water is separated, flows into the upstream side heat transfer tube 33a. The heating medium flowing into the Docket No. PMHA-13014-AU 25 upstream side heat transfer tube 33a flows into the first fluidization gas supply line 55 after heat is exchanged between the heating medium and brown coal in the first drying room 21. 5 [0074] The heating medium flowing into the first fluidization gas supply line 55 flows into the first gas liquid separator 57. Condensate water contained in a heating medium flowing into the first gas-liquid separator 57 is separated from the heating medium. The separated 10 condensate water is discharged by way of the condensate water discharge line 60, and the heating medium, from which the condensate water is separated, flows into the heater 58 as the first fluidization gas. The heater 58 heats the first fluidization gas by condensate water flowing in 15 through the second heating medium supply line 61. The first fluidization gas heated flows into the first chamber room 18. The first fluidization gas flowing into the first chamber room 18 is supplied to the first drying room 21, and then changes to exhaust gas again, and is discharged 20 from the gas outlet 13. [0075] As described in the foregoing, according to a configuration of the first embodiment, it is possible to dry brown coal in the first drying room 21 using the first fluidization gas having a low vapor concentration at an 25 initial stage, and dry brown coal in the second drying room 22 using the second fluidization gas having a high vapor concentration at a late stage. In this way, brown coal can be dried efficiently by decreasing a temperature of the first fluidization gas when compared to the second 30 fluidization gas as much as a low vapor concentration of the first fluidization gas. In addition, since drying of brown coal may be promoted as much as a low vapor concentration of the first fluidization gas when compared Docket No. PMHA-13014-AU 26 to the second fluidization gas, it is possible to suitably dry brown coal even when a temperature of the first fluidization gas is lower than that of the second fluidization gas. 5 [0076] In addition, according to a configuration of the first embodiment, since exhaust gas discharged from the drying room 12 through the gas outlet 13 may be used as a heating medium of the heat transfer tube 33, brown coal can be further dried efficiently as much as latent heat of the 10 exhaust gas that may be effectively used. [0077] In addition, according to a configuration of the first embodiment, since a heating medium discharged from the upstream side heat transfer tube 33a may be used as the first fluidization gas, brown coal can be further dried 15 efficiently as much as a heating medium that may be effectively used. In addition, since exhaust gas flowing through the first heating medium supply line 51 may be used as the second fluidization gas, brown coal can be further dried efficiently as much as latent heat of the exhaust gas 20 that may be effectively used. [0078] In addition, according to a configuration of the first embodiment, it is possible to separate condensate water contained in a heating medium discharged from the upstream side heat transfer tube 33a by the first gas 25 liquid separator 57, and use the heating medium, from which the condensate water is separated, as the first fluidization gas. In this way, the first fluidization gas after the separation of the condensate water has a low vapor concentration, and thus may be suitably used as the 30 first fluidization gas. [0079] In addition, according to a configuration of the first embodiment, it is possible to provide the upstream side heat transfer tube 33a in the first drying room 21, Docket No. PMHA-13014-AU 27 and provide the downstream side heat transfer tube 33b in the second drying room 22. For this reason, it is possible to dry brown coal by the first fluidization gas and the upstream side heat transfer tube 33a in the first drying 5 room 21 into which the first fluidization gas flows, and then dry brown coal by the second fluidization gas and the downstream side heat transfer tube 33b in the second drying room 22 into which the second fluidization gas flows. In this way, when brown coal supplied from the brown coal 10 supply port 31 flows along a flow direction, it is possible to inhibit the brown coal from being discharged from the brown coal discharge port 41 in a non-dry state, and suitably dry the brown coal. [0080] In addition, according to a configuration of the 15 first embodiment, it is possible to make a connection so that a heating medium flows from the downstream side heat transfer tube 33b toward the upstream side heat transfer tube 33a. For this reason, a temperature of the downstream side heat transfer tube 33b provided in the second drying 20 room 22 into which the second fluidization gas flows may be higher than a temperature of the upstream side heat transfer tube 33a provided in the first drying room 21 into which the first fluidization gas flows. In this way, it is possible to suitably dry brown coal without condensing 25 steam contained in the first fluidization gas and the second fluidization gas. [0081] In addition, according to a configuration of the first embodiment, since condensate water in a heating medium separated by the second gas-liquid separator 56 may 30 be used as a heating medium of the heater 58 that heats the first fluidization gas, brown coal can be further dried efficiently as much as condensate water that may be effectively used.

Docket No. PMHA-13014-AU 28 [0082] In addition, according to a configuration of the first embodiment, it is possible to divide the freeboard F by the upper partition plate 16 depending on the first drying room 21 and the second drying room 22. For this 5 reason, it is possible to suppress a condensation due to a mixture of exhaust gas generated in the first drying room 21 and exhaust gas generated in the second drying room 22. [0083] In the first embodiment, the upper partition plate 16 is provided on the freeboard F. However, the 10 invention is not limited to this configuration, and the upper partition plate 16 may be removed. [0084] In addition, the lower partition plate 15 connects the lower end portion to the gas dispersion board 6. However, the invention is not limited to this 15 configuration, and a void may be provided between the lower end portion and the gas dispersion board 6. In this case, the void may serve as a circulation opening that allows the first drying room 21 to communicate with the second drying room 22, and brown coal may be caused to flow from the 20 first drying room 21 to the second drying room 22 through the circulation opening. [0085] In addition, brown coal collected in the dust collector 139 is supplied to the dried coal bunker 132. However, the invention is not limited to this configuration, 25 and the brown coal may be returned to the fluidized bed drying apparatus 1. Second Embodiment [0086] Next, a fluidized bed drying apparatus 200 according to a second embodiment will be described with 30 reference to FIG. 3. FIG. 3 is a schematic configuration diagram schematically illustrating a fluidized bed drying apparatus according to the second embodiment. In the second embodiment, different portions will be described to Docket No. PMHA-13014-AU 29 avoid repeated description. In the fluidized bed drying apparatus 1 according to the first embodiment, exhaust gas discharged from the gas outlet 13 is compressed by the steam compressor 135. However, in the fluidized bed drying 5 apparatus 200 according to the second embodiment, a portion of exhaust gas discharged from a gas outlet 13 is compressed by a steam compressor 135. Hereinafter, the fluidized bed drying apparatus 200 according to the second embodiment will be described. 10 [0087] In the fluidized bed drying apparatus 200 of the second embodiment, a heat transfer tube 33 includes an upstream side heat transfer tube 33a provided on the inside of a fluidized bed 3 of a first drying room 21 and a downstream side heat transfer tube 33b provided on the 15 inside of the fluidized bed 3 of a second drying room 22. [0088] An inflow side of the downstream side heat transfer tube 33b is connected to the gas outlet 13 through a first heating medium supply line 51, and an outflow side thereof is connected to a second gas-liquid separator 56. 20 The first heating medium supply line 51 is provided with a dust collector 139 described above, and a downstream side of the dust collector 139 is provided with the steam compressor 135 described above. [0089] The second gas-liquid separator 56 separates 25 condensate water (condensate) contained in a heating medium which is discharged from the downstream side heat transfer tube 33b. The second gas-liquid separator 56 supplies the condensate water separated from the heating medium to a second heating medium supply line 61 provided with a second 30 flow rate adjusting valve 54. The condensate water supplied to the second heating medium supply line 61 is supplied to a heater 58. On the other hand, the second gas-liquid separator 56 supplies the heating medium, from Docket No. PMHA-13014-AU 30 which the condensate water is separated, to a first fluidization gas junction line 208. One end portion of the first fluidization gas junction line 208 is connected to the second gas-liquid separator 56, and the other end 5 portion thereof is connected to a first fluidization gas supply line 55. For this reason, the first fluidization gas junction line 208 supplies a heating medium, from which condensate water is separated, discharged from the second gas-liquid separator 56 to the first fluidization gas 10 supply line 55 as a first fluidization gas. [0090] An air bleed line 203 is connected to the first heating medium supply line 51 between the dust collector 139 and the steam compressor 135. One end portion of the air bleed line 203 is connected to the first heating medium 15 supply line 51, and the other end portion thereof is connected to an inflow side of the upstream side heat transfer tube 33a. The air bleed line 203 is provided with a first blower 205 which supplies bled exhaust gas toward the upstream side heat transfer tube 33a. In addition, a 20 second fluidization gas supply line 52 is connected to the air bleed line 203 on a downstream side of the first blower 205. One end portion of the second fluidization gas supply line 52 is connected to the air bleed line 203, and the other end portion thereof is connected to a second chamber 25 room 19. The second fluidization gas supply line 52 supplies exhaust gas, which is supplied by the first blower 205, to the second chamber room 19 as a second fluidization gas. [0091] An inflow side of the upstream side heat transfer 30 tube 33a is connected to the air bleed line 203, and an outflow side thereof is connected to the first fluidization gas supply line 55. The first fluidization gas supply line 55 is provided with a first gas-liquid separator 57, a Docket No. PMHA-13014-AU 31 downstream side of the first gas-liquid separator 57 is provided with the heater 58, and a downstream side of the heater 58 is provided with a second blower 206. [0092] Next, a flow of a heating medium of the heat 5 transfer tube 33 and exhaust gas in the fluidized bed drying apparatus 200 of the second embodiment will be described. When exhaust gas generated in the first drying room 21 and the second drying room 22 flows into the first heating medium supply line 51 through the gas outlet 13, 10 the exhaust gas passes through the dust collector 139 by way of the first heating medium supply line 51. A portion of the exhaust gas passing through the dust collector 139 flows into the air bleed line 203, and the other portion thereof flows into the steam compressor 135. 15 [0093] Exhaust gas passing through the steam compressor 135 changes to a heating medium, and flows into the downstream side heat transfer tube 33b by way of the first heating medium supply line 51. The heating medium flowing into the downstream side heat transfer tube 33b flows into 20 the second gas-liquid separator 56 after heat is exchanged between the heating medium and brown coal in the second drying room 22. Condensate water contained in a heating medium flowing into the second gas-liquid separator 56 is separated from the heating medium. The separated 25 condensate water flows into the heater 58 by way of the second heating medium supply line 61, and the heating medium, from which condensate water is separated, flows into the first fluidization gas junction line 208. [0094] On the other hand, exhaust gas flowing into the 30 air bleed line 203 passes through the first blower 205. A portion of the exhaust gas passing through the first blower 205 changes to the second fluidization gas, and flows into the second chamber room 19 by way of the second Docket No. PMHA-13014-AU 32 fluidization gas supply line 52. The second fluidization gas flowing into the second chamber room 19 is supplied to the second drying room 22, and then changes to exhaust gas again, and is discharged from the gas outlet 13. In 5 addition, the other portion of the exhaust gas passing through the first blower 205 changes to a heating medium, and flows into the upstream side heat transfer tube 33a. The heating medium flowing into the upstream side heat transfer tube 33a flows into the first fluidization gas 10 supply line 55 after heat is exchanged between the heating medium and brown coal in the first drying room 21. [0095] The heating medium, flowing into the first fluidization gas supply line 55, flows into the first gas liquid separator 57. Condensate water contained in the 15 heating medium flowing into the first gas-liquid separator 57 is separated from the heating medium. The separated condensate water is discharged through a condensate water discharge line 60, and the heating medium, from which condensate water is separated, flows into the heater 58 as 20 the first fluidization gas. The heater 58 heats the first fluidization gas by condensate water flowing in through the second heating medium supply line 61. The first fluidization gas heated passes through the second blower 206, joins the first fluidization gas flowing in from the 25 first fluidization gas junction line 208, and then flows into the first chamber room 18. The first fluidization gas flowing into the first chamber room 18 is supplied to the first drying room 21, and then changes to exhaust gas again, and is discharged from the gas outlet 13. 30 [0096] As described in the foregoing, in the configuration of the second embodiment, it is possible to dry brown coal in the first drying room 21 using the first fluidization gas having a low vapor concentration at an 33 initial stage, and dry brown coal in the second drying room 22 using the second fluidization gas having a high vapor concentration at a late stage. [0097] In addition, according to the configuration of 5 the second embodiment, since a flow rate of exhaust gas supplied to the steam compressor 135 may be reduced as much as exhaust gas, which flows through the first heating medium supply line 51, bled through the air bleed line 203, it is possible to reduce power of the steam compressor 135, 10 and enhance operating efficiency. Third Embodiment [0098] Next, a fluidized bed drying apparatus 210 according to a third embodiment will be described with reference to FIGS. 4 and 5. FIG. 4 is a schematic 15 configuration diagram schematically illustrating a fluidized bed drying apparatus according to the third embodiment, and FIG. 5 is a graph illustrating an enthalpy temperature curve of a heating medium flowing through a heat transfer tube, and an enthalpy-temperature curve of 20 brown coal that is being dried in the fluidized bed drying apparatus according to the third embodiment. In the third embodiment, different portions will be described to avoid repeated description. In the fluidized bed drying apparatus 210 according to the third embodiment, a 25 temperature of a drying room positioned on a downstream side of a flow direction is high when compared to a drying room positioned on an upstream side of the flow direction by adjusting a flow rate of fluidization gas flowing into a chamber room 11. Hereinafter, the fluidized bed drying 30 apparatus 210 according to the third embodiment will be described. [0099] The fluidized bed drying apparatus 210 according to the third embodiment is configured by increasing the Docket No. PMHA-13014-AU 34 number of chamber rooms 11 and drying rooms 12 in the fluidized bed drying apparatus 1 of the first embodiment. That is, the fluidized bed drying apparatus 210 includes a plurality of chamber partition plates 14, and a plurality 5 of lower partition plates 15. In the third embodiment, the upper partition plate 16 is not provided. [0100] The plurality of chamber partition plates 14 divide the chamber room 11 into a first chamber room 18, a second chamber room 19, and a third chamber room 212 in 10 order from an upstream side of a flow direction. In this instance, a first fluidization gas is supplied to the first chamber room 18 from a first fluidization gas supply line 55, and a second fluidization gas is supplied to the second chamber room 19 from a second fluidization gas supply line 15 52. In addition, a third fluidization gas supply line 215 is connected to the third chamber room 212. An end portion of the third fluidization gas supply line 215 is connected to a first heating medium supply line 51, and the other end portion thereof is connected to the third chamber room 212. 20 The third fluidization gas supply line 215 is provided with a third flow rate adjusting valve 216 which adjusts a flow rate of a third fluidization gas flowing into the third chamber room 212. [0101] In addition, the plurality of lower partition 25 plates 15 divides the drying room 12 into a first drying room 21, a second drying room 22, and a third drying room 213 in order from an upstream side of a flow direction. The first drying room 21 is provided with a first temperature sensor 221 on the inside of a fluidized bed 3, 30 the second drying room 22 is provided with a second temperature sensor 222 on the inside of the fluidized bed 3, and the third drying room 213 is provided with a third temperature sensor 223 on the inside of the fluidized bed 3.

35 In the third embodiment, each of the temperature sensors 221, 222, and 223 is provided on the inside of a fluidized bed 3. However, the invention is not limited thereto, and each of the temperature sensors may be provided on a 5 freeboard F. [0102] A heat transfer tube 33 includes a first heat transfer tube (upstream side heat transfer tube) 33a provided on the inside of the fluidized bed 3 of the first drying room 21, a second heat transfer tube (downstream 10 side heat transfer tube) 33b provided on the inside of the fluidized bed 3 of the second drying room 22, and a third heat transfer tube 33c provided on the inside of the fluidized bed 3 of the third drying room 213. The first heat transfer tube 33a, the second heat transfer tube 33b, 15 and the third heat transfer tube 33c are connected to one another so that a heating medium circulating through the inside of the heat transfer tube 33 flows from the downstream side toward the upstream side of the flow direction. 20 [0103] In this instance, a connecting part of the first heat transfer tube 33a and the second heat transfer tube 33b is provided with a second gas-liquid separator 56a, and a connecting part of the second heat transfer tube 33b and the third heat transfer tube 33c is provided with a second 25 gas-liquid separator 56b. In addition, condensate water separated in the second gas-liquid separators 56a and 56b is supplied to a second heating medium supply line 61. [0104] Herein a control device 220 provided in the fluidized bed drying apparatus 210 is connected to the 30 first temperature sensor 221, the second temperature sensor 222, and the third temperature sensor 223, and is connected to a first flow rate adjusting valve 53 and the third flow rate adjusting valve 216. The control device 220 adjusts a Docket No. PMHA-13014-AU 36 flow rate of the first fluidization gas, the second fluidization gas, and the third fluidization gas by controlling the first flow rate adjusting valve 53 and the third flow rate adjusting valve 216 based on a detected 5 temperature of each of the temperature sensors 221, 222, and 223, and performs a control such that a temperature of the respective drying rooms 22 and 213 positioned on a downstream side of a flow direction is higher than a temperature of the respective drying rooms 21 and 22 10 positioned on an upstream side of the flow direction. [0105] Specifically, when a temperature of the second drying room 22 is higher than a temperature of the first drying room 21, the control device 220 decreases a flow rate of the second fluidization gas flowing into the second 15 drying room 22 by controlling the first flow rate adjusting valve 53 so that the valve is closed. Similarly, when a temperature of the third drying room 213 is higher than a temperature of the second drying room 22, a flow rate of the third fluidization gas flowing into the third drying 20 room 213 is decreased by controlling the third flow rate adjusting valve 216 so that the valve is closed. The control device 220 is connected to a second flow rate adjusting valve 54 and a pressure reducing valve 59 which are appropriately controlled. 25 [0106] Next, an enthalpy-temperature curve of a heating medium flowing through the heat transfer tube 33, and an enthalpy-temperature curve of brown coal that is being dried in the fluidized bed drying apparatus 210 according to the third embodiment will be described with reference to 30 FIG. 5. In the graph illustrated in FIG. 5, Li depicts the enthalpy-temperature curve of a heating medium flowing through the heat transfer tube 33, and L2 depicts the enthalpy-temperature curve of brown coal before being dried.

Docket No. PMHA-13014-AU 37 In FIG. 5, a left side of the drawing corresponds to an upstream side of a flow direction, and a right side of the drawing corresponds to a downstream side of the flow direction. For this reason, a range from an uppermost 5 stream to a step portion of an upstream side of the temperature curve L2 illustrates a range of the first drying room 21, a range from the step portion of an upstream side to a step portion of a downstream side of the temperature curve L2 illustrates a range of the second 10 drying room 22, and a range from the step portion of a downstream side of the temperature curve L2 to a bent portion of the temperature curve Li illustrates a range of the third drying room 213. As illustrated in FIG. 5, it is verified that brown coal is suitably dried since a 15 temperature difference is obtained between the temperature curve Li and the temperature curve L2. [0107] As described in the foregoing, in the third embodiment, it is possible to dry brown coal in the first drying room 21 using the first fluidization gas having a 20 low vapor concentration at an initial stage, and dry brown coal in the second drying room 22 using the second fluidization gas having a high vapor concentration at a late stage. [0108] In addition, according to a configuration of the 25 third embodiment, it is possible to increase a temperature of the respective drying rooms 22 and 213 positioned on a downstream side of a flow direction when compared to the respective drying rooms 21 and 22 positioned on an upstream side of the flow direction by controlling the first flow 30 rate adjusting valve 53 and the third flow rate adjusting valve 216 based on a detected temperature of the respective temperature sensors 221, 222, and 223. In this way, since latent heat of exhaust gas may be appropriately distributed Docket No. PMHA-13014-AU 38 as each fluidization gas, it is possible to efficiently use the latent heat of exhaust gas. Fourth Embodiment [0109] Next, a fluidized bed drying apparatus 230 5 according to a fourth embodiment will be described with reference to FIGS. 6 and 7. FIG. 6 is a schematic configuration diagram schematically illustrating a fluidized bed drying apparatus according to the fourth embodiment, and FIG. 7 is a graph illustrating an enthalpy 10 temperature curve of a heating medium flowing through a heat transfer tube, and an enthalpy-temperature curve of brown coal that is being dried in the fluidized bed drying apparatus according to the fourth embodiment. In the fourth embodiment, different portions will be described to 15 avoid repeated description. The fluidized bed drying apparatus 230 according to the fourth embodiment had a configuration in which a drying room 12 is not divided into a plurality of drying rooms, and a heat transfer tube 33 corresponding to a single body is provided in the drying 20 room 12 according to the configuration. [0110] That is, the fluidized bed drying apparatus 230 according to the fourth embodiment has a configuration in which the lower partition plate 15 and the upper partition plate 16 are removed. The heat transfer tube 33 provided 25 in the drying room 12 has a configuration in which a heating medium circulating through the inside flows from a downstream side toward an upstream side of a flow direction. A shape of the heat transfer tube 33 may be a linear shape or a shape of bellows, and is not particularly limited. 30 [0111] Next, an enthalpy-temperature curve of a heating medium flowing through the heat transfer tube 33, and an enthalpy-temperature curve of brown coal that is being dried in the fluidized bed drying apparatus 230 according Docket No. PMHA-13014-AU 39 to the fourth embodiment will be described with reference to FIG. 7. In the graph illustrated in FIG. 7, Li depicts the enthalpy-temperature curve of a heating medium flowing through the heat transfer tube 33, and L2 depicts the 5 enthalpy-temperature curve of brown coal before being dried. In FIG. 7, a left side of the drawing corresponds to an upstream side of a flow direction, and a right side of the drawing corresponds to a downstream side of the flow direction. As illustrated in FIG. 7, it is verified that 10 brown coal is suitably dried since the temperature curve Li may stably obtain a given temperature difference between the temperature curve Li and the temperature curve L2 in a range from an upstream side to a downstream side of a flow direction. 15 [0112] As described in the foregoing, according to a configuration of the fourth embodiment, it is possible to dry brown coal on an upstream side of a flow direction of the drying room 12 using a first fluidization gas having a low vapor concentration at an initial stage, and dry brown 20 coal on a downstream side of the flow direction of the drying room 12 using a second fluidization gas having a high vapor concentration at a late stage. In this instance, since a configuration of the fluidized bed drying apparatus 230 may be simple, it is possible to reduce a device cost. 25 Reference Signs List [0113] 1 FLUIDIZED BED DRYING APPARATUS 3 FLUIDIZED BED 5 DRYING FURNACE 6 GAS DISPERSION BOARD 30 11 CHAMBER ROOM 12 DRYING ROOM 13 GAS OUTLET 14 CHAMBER PARTITION PLATE Docket No. PMHA-13014-AU 40 15 LOWER PARTITION PLATE 16 UPPER PARTITION PLATE 18 FIRST CHAMBER ROOM 19 SECOND CHAMBER ROOM 5 21 FIRST DRYING ROOM 22 SECOND DRYING ROOM 31 SUPPLY PORT 33 HEAT TRANSFER TUBE 41 DISCHARGE PORT 10 51 FIRST HEATING MEDIUM SUPPLY LINE 52 SECOND FLUIDIZATION GAS SUPPLY LINE 53 FIRST FLOW RATE ADJUSTING VALVE 54 SECOND FLOW RATE ADJUSTING VALVE 55 FIRST FLUIDIZATION GAS SUPPLY LINE 15 56 SECOND GAS-LIQUID SEPARATOR 57 FIRST GAS-LIQUID SEPARATOR 58 HEATER 59 PRESSURE REDUCING VALVE 60 CONDENSATE WATER DISCHARGE LINE 20 61 SECOND HEATING MEDIUM SUPPLY LINE 200 FLUIDIZED BED DRYING APPARATUS (EXAMPLE 2) 203 AIR BLEED LINE 205 FIRST BLOWER 206 SECOND BLOWER 25 208 FIRST FLUIDIZATION GAS JUNCTION LINE 210 FLUIDIZED BED DRYING APPARATUS (EXAMPLE 3) 212 THIRD CHAMBER ROOM 213 THIRD DRYING ROOM 215 THIRD FLUIDIZATION GAS SUPPLY LINE 30 216 THIRD FLOW RATE ADJUSTING VALVE 220 CONTROL DEVICE 221 FIRST TEMPERATURE SENSOR 222 SECOND TEMPERATURE SENSOR Docket No. PMHA-13014-AU 41 223 THIRD TEMPERATURE SENSOR 230 FLUIDIZED BED DRYING APPARATUS (EXAMPLE 4) F FREEBOARD

Claims

1. A fluidized bed drying apparatus for drying a wet fuel while a fluidized bed is formed by causing the wet fuel to flow using fluidization gas, comprising: 5 a drying furnace; and a gas blowing unit for dividing an inside of the drying furnace into a chamber room into which the fluidization gas flows and a drying room into which the wet fuel is supplied, and for causing the fluidization gas to 10 flow from the chamber room into the drying room, wherein a plurality of chamber rooms are disposed along a flow direction of the wet fuel, a first fluidization gas having a low vapor concentration flows into the chamber room positioned on an 15 upstream side of the flow direction, and a second fluidization gas having a relatively high vapor concentration compared to the first fluidization gas flows into the chamber room positioned on a downstream side of the flow direction. 20

2. The fluidized bed drying apparatus according to claim 1, further comprising: a heat transfer tube provided in the drying room, for flowing a heating medium circulating through the inside 25 from a downstream side toward an upstream side of the flow direction; a gas outlet for discharging exhaust gas generated in the drying room; a first heating medium supply line connecting the gas 30 outlet to an inflow side of the heat transfer tube; and a compressor provided on the first heating medium supply line, for compressing the exhaust gas so as to supply the exhaust gas as the heating medium of the heat 43 transfer tube.

3. The fluidized bed drying apparatus according to claim 2, further comprising: 5 a first fluidization gas supply line connecting an outflow side of the heat transfer tube to the chamber room positioned on the upstream side of the flow direction; and a second fluidization gas supply line connecting the first heating medium supply line to the chamber room 10 positioned on the downstream side of the flow direction.

4. The fluidized bed drying apparatus according to claim 3, further comprising a first gas-liquid separator provided on the first 15 fluidization gas supply line, for separating condensate contained in the heating medium discharged from the heat transfer tube.

5. The fluidized bed drying apparatus according to any 20 one of claims 2 to 4, further comprising a first partition member for dividing the drying room into a plurality of drying rooms corresponding to the plurality of chamber rooms, wherein the heat transfer tube is provided in each of 25 the plurality of drying rooms.

6. The fluidized bed drying apparatus according to claim 5, further comprising; a temperature detection sensor provided in the 30 plurality of drying rooms; a flow rate adjusting valve for adjusting a flow rate of the second fluidization gas; and a control device for controlling the flow rate 44 adjusting valve based on a detected temperature of the temperature detection sensor, wherein the control device is configured to control the flow rate adjusting valve so that a temperature of the 5 drying room positioned on a downstream side of the flow direction is high when compared to the drying room positioned on an upstream side of the flow direction.

7. The fluidized bed drying apparatus according to claim 10 5 or 6, wherein the plurality of heat transfer tubes provided in the plurality of chamber rooms are connected to one another so that the heating medium flows from the heat transfer tube positioned on a downstream side of the flow 15 direction toward the heat transfer tube positioned on an upstream side of the flow direction.

8. The fluidized bed drying apparatus according to claim 7, further comprising: 20 a second gas-liquid separator provided in a connecting part of the heat transfer tube positioned on a downstream side of the flow direction and the heat transfer tube positioned on an upstream side of the flow direction, the second gas-liquid separator being adapted to separate 25 condensate contained in the heating medium; a heater for heating the first fluidization gas; and a second heating medium supply line for introducing the condensate separated in the second gas-liquid separator into the heater as a heating medium of the heater. 30

9. The fluidized bed drying apparatus according to claim 5 or 6, further comprising an air bleed line for bleeding the exhaust gas from 45 the first heating medium supply line, wherein the first heating medium supply line connects the gas outlet to an inflow side of the heat transfer tube positioned on the downstream side, 5 the air bleed line connects the first heating medium supply line to an inflow side of the heat transfer tube positioned on the upstream side, and the compressor is provided on the first heating medium supply line positioned on a downstream side of a connecting 10 part where the first heating medium supply line is connected to the air bleed line.

10. The fluidized bed drying apparatus according to any one of claims 5 to 9, further comprising 15 a second partition member provided in the drying furnace, for dividing a freeboard positioned on an upper portion of the fluidized bed formed in the plurality of drying rooms into a plurality of freeboards corresponding to the plurality of drying rooms.