JP2013178028A - Fluid bed drying device, integrated gasification combined cycle facility and drying method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fluid bed drying device capable of appropriately drying wet fuel such as brown coal capable of improving the recovery efficiency of the latent heat of steam.SOLUTION: A fluid bed drying device includes a drying furnace 5, a fluidizing steam supply part 21 for supplying fluidizing steam to the drying furnace 5, heat transfer pipes 33 and 43 for heating brown coal in the drying furnace 5, and a steam compressor 135 which compresses the steam discharged from a lower stream side drying chamber 12b and supplies it to the heat transfer pipes 33 and 43. The drying furnace 5 includes an upper stream side drying chamber 12a and the lower stream side drying chamber 12b. The heat transfer pipes 33 and 43 include the upper stream side heat transfer pipe 33 provided in the upper stream side drying chamber 12a, and the lower stream side heat transfer pipe 43 provided in the lower stream side drying chamber 12b. The steam from the steam compressor 135 flows in the lower stream side heat transfer pipe 43, and then flows to the upper stream side heat transfer pipe 33. The fluidizing steam supply pipe 21 supplies fluidizing steam to the upper stream side drying chamber 12a and the lower stream side drying chamber 12b, and supplies the fluidizing gas which contains more non-condensable gas than the lower stream side drying chamber 12b to the upper stream side drying chamber 12a.

Description

  The present invention relates to a fluidized bed drying apparatus, a gasification combined power generation facility, and a drying method for drying while flowing wet fuel such as lignite.

  Conventionally, a low-grade coal drying method and apparatus for supplying low-grade coal, such as brown coal, from a hopper to a drying vessel, and flowing the low-grade coal supplied in the drying vessel with steam (steam) to dry it is known. (For example, refer to Patent Document 1). In this low-grade coal drying apparatus, the steam discharged from the drying vessel is supplied to the partial condenser to recover the latent heat of the steam.

Japanese Patent Laid-Open No. 61-250096

  By the way, in the fluidized bed drying apparatus which dries while wet fuel, such as lignite, is made to flow with fluidized steam (steam), the steam discharged from the fluidized bed drying apparatus may be recompressed and used. Here, in the fluidized bed drying apparatus, it is difficult to eliminate the mixing of non-condensable gas such as air containing nitrogen. For this reason, non-condensable gas is mixed in the recompressed steam. The recompressed steam is used, for example, for heating the wet fuel, and heat exchange is performed with the wet fuel. In this case, the heat of the recompressed steam is exchanged with the wet fuel, so that the quality of the steam is lowered. When the quality of the steam decreases, the ratio of the liquid-phase steam (ie, condensed water) to the total amount of steam increases, so the low-quality steam increases the ratio of non-condensable gas contained in the gas phase. To do. Thereby, the vapor | steam which became low quality will reduce vapor | steam temperature because the ratio of the non-condensable gas contained in a gaseous phase increases. For this reason, when trying to heat the wet fuel with low-quality steam whose steam temperature has been lowered, it has been difficult to suitably ensure a temperature difference between the steam temperature and the wet fuel.

  Therefore, the present invention provides a fluidized bed drying apparatus and a drying method capable of improving the recovery efficiency of the latent heat of steam by suitably drying the wet fuel using the steam having a low quality. This is the issue.

  The fluidized bed drying apparatus of the present invention includes a drying furnace in which wet fuel is supplied, and fluidization that forms a fluidized bed in the drying furnace by supplying fluidized steam to the drying furnace and causing the wet fuel to flow. A steam supply unit, a heat transfer member that is provided in the drying furnace and heats the supplied wet fuel, and a compressor that compresses the steam discharged from the drying furnace and supplies the compressed steam toward the heat transfer member And the drying furnace has an upstream drying chamber provided on the upstream side in the flow direction of the wet fuel, and a downstream drying chamber provided on the downstream side of the upstream drying chamber, and the heat transfer member is It has an upstream heat transfer member provided in the upstream drying chamber and a downstream heat transfer member provided in the downstream drying chamber, and steam supplied from the compressor circulated through the downstream heat transfer member. After that, it is provided to circulate the upstream heat transfer member, and the compressor is discharged from the downstream drying chamber. The fluidized steam supply unit compresses the gas and supplies the fluidized steam to the upstream drying chamber and the downstream drying chamber, and has a higher content of non-condensable gas than the downstream drying chamber. Is supplied to the upstream drying chamber.

  According to this configuration, while the wet fuel in the upstream drying chamber is fluidized with fluidized steam having a high content of non-condensable gas, low-quality steam with a high proportion of non-condensable gas in the gas phase is generated. It can heat with the circulating upstream heat transfer member. On the other hand, while the wet fuel in the downstream drying chamber is fluidized by fluidized steam, it can be heated by a downstream heat transfer member through which high-quality steam with a small proportion of non-condensable gas in the gas phase flows. it can. For this reason, in the upstream drying chamber, the dew point temperature in the upstream drying chamber can be reduced by using fluidized steam having a high content of non-condensable gas. The wet fuel flowing through can also be dried at low temperatures. As a result, even in the upstream drying chamber, even with low quality steam, the wet fuel can be suitably dried, so that low quality steam can be used effectively and the latent heat of steam can be efficiently recovered. can do.

  In this case, the drying furnace is preferably divided into an upstream drying furnace that forms the upstream drying chamber and a downstream drying furnace that forms the downstream drying chamber.

  According to this configuration, since the drying furnace can be divided into the upstream drying furnace and the downstream drying furnace, the fluidized gas supplied into the upstream drying furnace is mixed into the downstream drying furnace. Can be suppressed.

  In this case, the drying furnace preferably has a partition plate that divides the interior into an upstream drying chamber and a downstream drying chamber.

  According to this configuration, since the drying furnace can be divided into the upstream drying chamber and the downstream drying chamber by the partition plate, the drying furnace can be simplified.

  In this case, a gas-liquid separation device that gas-liquid separates the steam flowing from the downstream heat transfer member and supplies the vapor in the vapor phase to the upstream heat transfer member while discharging the vapor in the liquid phase as condensed water. Further, it is preferable to further provide.

  According to this configuration, the vapor of the vapor phase supplied to the upstream heat transfer member is increased by discharging the vapor of the liquid phase flowing through the downstream heat transfer member as condensed water by the gas-liquid separator. be able to. That is, the gas-liquid separation device can convert a low-quality vapor having a large proportion of non-condensable gas in the gas phase into a high-quality vapor having a large proportion of non-condensable gas in the gas phase. Thereby, since the inflow of the liquid-phase vapor | steam can be suppressed to an upstream heat-transfer member, formation of the liquid film inside an upstream heat-transfer member can be suppressed, and the improvement of a heat transfer rate can be aimed at. it can.

  A gasification combined power generation facility of the present invention includes the above fluidized bed drying apparatus, a gasification furnace that processes the wet fuel after drying supplied from the fluidized bed drying apparatus and converts it into gasification gas, and gasification gas A gas turbine operated as fuel, a steam turbine operated by steam generated by an exhaust heat recovery boiler that introduces turbine exhaust gas from the gas turbine, and a generator connected to the gas turbine and the steam turbine It is characterized by.

  According to this configuration, the recovery efficiency of the latent heat of the steam can be improved in the fluidized bed drying apparatus, so that the latent heat can be effectively used and the power generation efficiency of the generator connected to the steam turbine can be improved.

  The drying method of the present invention is a drying method in which the wet fuel is dried by heating the wet fuel with a heat transfer member provided in the drying furnace while flowing the wet fuel supplied into the drying furnace with fluidized steam. In this method, the drying furnace has an upstream drying chamber provided on the upstream side in the flow direction of the wet fuel, and a downstream drying chamber provided on the downstream side of the upstream drying chamber, and the heat transfer member is A flow having an upstream heat transfer member provided in the upstream drying chamber and a downstream heat transfer member provided in the downstream drying chamber, and supplying fluidized steam to the upstream drying chamber and the downstream drying chamber A vaporized gas supply step, a fluidized gas supply step of supplying fluidized vapor having a higher content of non-condensable gas as a fluidized gas to the upstream drying chamber as compared with the downstream drying chamber, and drying wet fuel A steam discharge process for discharging the generated steam from the downstream drying chamber; A steam compression process for compressing the steam discharged in the air discharge process, a downstream steam supply process for supplying the steam compressed in the steam compression process to the downstream heat transfer member, and a steam that has circulated through the downstream heat transfer member. And an upstream steam supply step for supplying the upstream heat transfer member.

  According to this configuration, while the wet fuel in the upstream drying chamber is fluidized with fluidized steam having a high content of non-condensable gas, low-quality steam with a high proportion of non-condensable gas in the gas phase is generated. It can heat with the circulating upstream heat transfer member. On the other hand, while the wet fuel in the downstream drying chamber is fluidized by fluidized steam, it can be heated by a downstream heat transfer member through which high-quality steam with a small proportion of non-condensable gas in the gas phase flows. it can. For this reason, in the upstream drying chamber, the dew point temperature in the upstream drying chamber can be reduced by using fluidized steam having a high content of non-condensable gas. The wet fuel flowing through can also be dried at low temperatures. As a result, even in the upstream drying chamber, even with low quality steam, the wet fuel can be suitably dried, so that low quality steam can be used effectively and the latent heat of steam can be efficiently recovered. can do.

  According to the fluidized bed drying apparatus, the gasification combined power generation facility and the drying method of the present invention, the wet fuel can be suitably dried by the low quality steam having a large proportion of the non-condensable gas in the gas phase. Low quality steam can be used effectively, and the latent heat of steam can be efficiently recovered.

FIG. 1 is a schematic configuration diagram of a coal gasification combined power generation facility to which a fluidized bed drying apparatus according to a first embodiment is applied. FIG. 2 is a schematic configuration diagram schematically illustrating the fluidized bed drying apparatus according to the first embodiment. FIG. 3 is a graph of an example relating to the quality of recompressed steam in the fluidized bed drying apparatus according to the first embodiment. FIG. 4 is a graph of an example regarding the quality of recompressed steam in the fluidized bed drying apparatus according to the first embodiment. FIG. 5 is a schematic configuration diagram schematically illustrating the fluidized bed drying apparatus according to the second embodiment. FIG. 6 is a schematic configuration diagram schematically illustrating a fluidized bed drying apparatus according to the first modification. FIG. 7 is a schematic configuration diagram schematically illustrating a fluidized bed drying apparatus according to the second modification. FIG. 8 is a schematic configuration diagram schematically showing a fluidized bed drying apparatus according to Modification 3. FIG. 9 is a schematic configuration diagram schematically illustrating a fluidized bed drying apparatus according to Modification 4. FIG. 10 is a schematic configuration diagram schematically illustrating a fluidized bed drying apparatus according to Modification 5. FIG. 11 is a schematic configuration diagram schematically illustrating a fluidized bed drying apparatus according to Modification 6.

  Hereinafter, a fluidized bed drying apparatus, a gasification combined power generation facility, and a drying method according to the present invention will be described with reference to the accompanying drawings. The present invention is not limited to the following examples. In addition, constituent elements in the following embodiments include those that can be easily replaced by those skilled in the art or those that are substantially the same.

  FIG. 1 is a schematic configuration diagram of a coal gasification combined power generation facility to which a fluidized bed drying apparatus according to a first embodiment is applied. An integrated coal gasification combined cycle (IGCC) 100 to which the fluidized bed drying apparatus 1 of Example 1 is applied employs an air combustion system that generates coal gas in a gasification furnace using air as an oxidant. The coal gas refined by the gas purifier is supplied as fuel gas to the gas turbine equipment for power generation. That is, the combined coal gasification combined power generation facility 100 according to the first embodiment is an air combustion type (air blowing) power generation facility. In this case, lignite is used as wet fuel supplied to the gasifier.

  In Example 1, lignite was used as the wet fuel, but low-grade coal including sub-bituminous coal, peat such as sludge, etc. may be applied as long as the moisture content is high. Even charcoal is applicable. In addition, the wet fuel is not limited to coal such as lignite, but may be biomass used as organic resources derived from renewable organisms. For example, thinned wood, waste wood, driftwood, grass, waste, It is also possible to use sludge, tires, and recycled fuel (pellets and chips) made from these raw materials.

  In Example 1, as shown in FIG. 1, the coal gasification combined power generation facility 100 includes a coal supply device 111, a fluidized bed drying device 1, a pulverized coal machine 113, a coal gasification furnace 114, a char recovery device 115, a gas refining device. A device 116, a gas turbine facility 117, a steam turbine facility 118, a generator 119, and a heat recovery steam generator (HRSG) 120 are provided.

  The coal feeder 111 includes a raw coal bunker 121, a coal feeder 122, and a crusher 123. The raw coal bunker 121 can store lignite, and drops a predetermined amount of lignite into the coal feeder 122. The coal feeder 122 transports the brown coal dropped from the raw coal bunker 121 by a conveyor or the like and drops it on the crusher 123. The crusher 123 finely pulverizes the dropped lignite into fine particles.

  As will be described in detail later, the fluidized bed drying apparatus 1 causes the lignite to contain lignite by flowing the lignite supplied from the coal feeder 111 with a fluidizing gas such as water vapor and heating and drying the heat transfer tubes 33 and 43. It removes moisture. The fluidized bed drying apparatus 1 is connected to a cooler 131 for cooling the discharged dried lignite (dry coal). The cooler 131 is connected to a dry charcoal bunker 132 for storing cooled dry charcoal. In addition, a dry coal cyclone 133 and a dry coal electric dust collector 134 are connected to the fluidized bed dryer 1 as a dust collector 139 for separating dry coal particles from exhaust gas discharged to the outside. The dry coal particles separated from the exhaust gas in the dry coal cyclone 133 and the dry coal electrostatic precipitator 134 are stored in the dry coal bunker 132. The exhaust gas from which the dry coal has been separated by the dry coal electrostatic precipitator 134 is compressed by the steam compressor 135 and then supplied to the heat transfer tubes 33 and 43 of the fluidized bed drying device 1 as a heat medium.

  The pulverized coal machine 113 produces pulverized coal by pulverizing lignite (dried coal) dried by the fluidized bed drying apparatus 1 into fine particles. In other words, when the dry coal stored in the dry coal bunker 132 is dropped by the coal feeder 136, the pulverized coal machine 113 converts the dry coal into pulverized coal having a predetermined particle size or less. The pulverized coal after being pulverized by the pulverized coal machine 113 is separated from the conveying gas by the pulverized coal bag filters 137a and 137b and stored in the pulverized coal supply hoppers 138a and 138b.

  The coal gasifier 114 is supplied with pulverized coal processed by the pulverized coal machine 113 and supplied with char (unburned coal) recovered by the char recovery device 115.

  The coal gasification furnace 114 is connected to a compressed air supply line 141 from a gas turbine facility 117 (compressor 161), and can supply compressed air compressed by the gas turbine facility 117. The air separation device 142 separates and generates nitrogen and oxygen from air in the atmosphere. A first nitrogen supply line 143 is connected to the coal gasifier 114, and a pulverized coal supply hopper is connected to the first nitrogen supply line 143. Charging lines 144a and 144b from 138a and 138b are connected. The second nitrogen supply line 145 is also connected to the coal gasifier 114, and the char return line 146 from the char recovery device 115 is connected to the second nitrogen supply line 145. Further, the oxygen supply line 147 is connected to the compressed air supply line 141. In this case, nitrogen is used as a carrier gas for coal and char, and oxygen is used as an oxidant.

  The coal gasification furnace 114 is, for example, a spouted bed type gasification furnace, which combusts and gasifies coal, char, oxidant (oxygen) supplied therein, or water vapor as a gasification agent, A combustible gas (generated gas, coal gas) containing carbon dioxide as a main component is generated, and a gasification reaction takes place using this combustible gas as a gasifying agent. Note that the coal gasification furnace 114 is provided with a foreign matter removing device 148 that removes foreign matter mixed with pulverized coal. In this case, the coal gasification furnace 114 is not limited to the spouted bed gasification furnace, and may be a fluidized bed gasification furnace or a fixed bed gasification furnace. The coal gasification furnace 114 is provided with a gas generation line 149 for combustible gas toward the char recovery device 115, and can discharge combustible gas containing char. In this case, by providing a gas cooler in the gas generation line 149, the combustible gas may be cooled to a predetermined temperature and then supplied to the char recovery device 115.

  The char recovery device 115 includes a dust collector 151 and a supply hopper 152. In this case, the dust collector 151 is constituted by one or a plurality of bag filters or cyclones, and can separate the char contained in the combustible gas generated in the coal gasification furnace 114. The combustible gas from which the char has been separated is sent to the gas purifier 116 through the gas discharge line 153. The supply hopper 152 stores the char 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 connected to the bin. A 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 by removing impurities such as sulfur compounds and nitrogen compounds from the combustible gas from which the char has been separated by the char recovery device 115. The gas purifier 116 purifies the combustible gas to produce fuel gas, and supplies it to the gas turbine equipment 117. In this gas purifier 116, since the combustible gas from which the char is separated still contains sulfur (H ₂ S), the sulfur is finally removed by removing it with the amine absorbent. Is recovered as gypsum and used effectively.

  The gas turbine equipment 117 includes a compressor 161, a combustor 162, and a turbine 163, and the compressor 161 and the turbine 163 are connected by a rotating shaft 164. The combustor 162 has a compressed air supply line 165 connected from the compressor 161, a fuel gas supply line 166 connected from the gas purification device 116, and a combustion gas supply line 167 connected to the turbine 163. Further, the gas turbine equipment 117 is provided with a compressed air supply line 141 extending from the compressor 161 to the coal gasification furnace 114, and a booster 168 is interposed in the compressed air supply line 141. Therefore, in the combustor 162, the compressed air supplied from the compressor 161 and the fuel gas supplied from the gas purifier 116 are mixed and burned, and the rotating shaft 164 is rotated by the generated combustion gas in the turbine 163. By doing so, the generator 119 can be driven.

  The steam turbine equipment 118 has a turbine 169 connected to the rotating shaft 164 in the gas turbine equipment 117, and the generator 119 is connected to the base end portion of the rotating shaft 164. The exhaust heat recovery boiler 120 is provided in the exhaust gas line 170 from the gas turbine equipment 117 (the turbine 163), and generates steam by exchanging heat between air and high-temperature exhaust gas. Therefore, the exhaust heat recovery boiler 120 is provided with a steam supply line 171 and a steam recovery line 172 between the turbine 169 of the steam turbine equipment 118, and a condenser 173 is provided in the steam recovery line 172. Yes. Therefore, in the steam turbine equipment 118, the turbine 169 is driven by the steam supplied from the exhaust heat recovery boiler 120, and the generator 119 can be driven by rotating the rotating shaft 164.

  The exhaust gas from which heat has been recovered by the exhaust heat recovery boiler 120 is removed of harmful substances by the gas purification device 174, and the purified exhaust gas is discharged from the chimney 175 to the atmosphere.

  Here, the action | operation of the coal gasification combined cycle power generation equipment 100 of Example 1 is demonstrated.

  In the combined coal gasification combined power generation facility 100 of the first embodiment, raw coal (brown coal) is stored in the raw coal bunker 121 by the coal feeder 111, and the lignite in the raw coal bunker 121 is crushed by the coal feeder 122. It is dropped to 123, where it is crushed to a predetermined size. The crushed lignite is heated and dried by the fluidized bed drying apparatus 1, cooled by the cooler 131, and stored in the dry coal bunker 132. Further, the exhaust gas discharged from the fluidized bed drying apparatus 1 is separated from the dry coal particles by the dry coal cyclone 133 and the dry coal electrostatic precipitator 134 and compressed by the steam compressor 135, and then transmitted to the fluidized bed drying apparatus 1. It returns to the heat pipes 33 and 43 as a heat medium. On the other hand, dry coal particles separated from the steam are stored in the dry coal bunker 132.

  The dry coal stored in the dry coal bunker 132 is supplied to the pulverized coal machine 113 by the coal feeder 136, where it is pulverized into fine particles to produce pulverized coal, and the pulverized coal bag filters 137a and 137b are used. And stored in pulverized coal supply hoppers 138a and 138b. The pulverized coal stored in the pulverized coal supply hoppers 138 a and 138 b is supplied to the coal gasification furnace 114 through the first nitrogen supply line 143 by nitrogen supplied from the air separation device 142. Further, the char recovered by the char recovery device 115 described later is supplied to the coal gasifier 114 through the second nitrogen supply line 145 by nitrogen supplied from the air separation device 142. Further, compressed air extracted from a gas turbine facility 117 described later is boosted by a booster 168 and then supplied to the coal gasifier 114 through the compressed air supply line 141 together with oxygen supplied from the air separation device 142.

  In the coal gasification furnace 114, the supplied pulverized coal and char are combusted by compressed air (oxygen), and the pulverized coal and char are gasified, so that combustible gas (coal gas) mainly containing carbon dioxide is obtained. Can be generated. This combustible gas is discharged from the coal gasifier 114 through the gas generation line 149 and sent to the char recovery device 115.

  In the char recovery device 115, the combustible gas is first supplied to the dust collector 151, and the dust collector 151 separates the char contained in the combustible gas. The combustible gas from which the char has been separated is sent to the gas purifier 116 through the gas discharge line 153. On the other hand, the fine char separated from the combustible gas is deposited on the supply hopper 152, returned to the coal gasifier 114 through the char return line 146, and recycled.

  The combustible gas from which the char has been separated by the char recovery device 115 is gas purified by removing impurities such as sulfur compounds and nitrogen compounds by the gas purification device 116 to produce fuel gas. In the gas turbine equipment 117, when the compressor 161 generates compressed air and supplies the compressed air to the combustor 162, the combustor 162 is supplied from the compressed air supplied from the compressor 161 and the gas purifier 116. Combustion gas is generated by mixing with fuel gas and combusting, and the turbine 163 is driven by this combustion gas, so that the generator 119 is driven via the rotating shaft 164 to generate power.

  The exhaust gas discharged from the turbine 163 in the gas turbine facility 117 generates steam by exchanging heat with air in the exhaust heat recovery boiler 120, and supplies the generated steam to the steam turbine facility 118. . In the steam turbine equipment 118, the turbine 169 is driven by the steam supplied from the exhaust heat recovery boiler 120, whereby the generator 119 can be driven via the rotating shaft 164 to generate power.

  Thereafter, in the gas purification device 174, harmful substances in the exhaust gas discharged from the exhaust heat recovery boiler 120 are removed, and the purified exhaust gas is released from the chimney 175 to the atmosphere.

  Hereinafter, the fluidized bed drying apparatus 1 in the coal gasification combined power generation facility 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 apparatus 1 of Example 1 heat-drys the lignite input by the coal feeder 111 while flowing it with a fluidizing gas.

  As shown in FIG. 2, the fluidized bed drying apparatus 1 includes a drying furnace 5 in which lignite is supplied. The drying furnace 5 includes an upstream drying furnace 5a and a downstream drying furnace 5b. An upstream gas dispersion plate 6a is provided in the upstream drying furnace 5a, and a downstream gas dispersion plate 6b is provided in the downstream drying furnace 5b. The upstream drying furnace 5a and the downstream drying furnace 5b are formed in a rectangular box shape. The upstream gas dispersion plate 6a includes an upstream air chamber 11a located on the lower side in the vertical direction (lower side in the figure) and an upstream located on the upper side in the vertical direction (upper side in the figure). It is divided into a side drying chamber 12a. Similarly, the downstream gas dispersion plate 6b has a space inside the downstream drying furnace 5b on the downstream wind chamber 11b located on the lower side in the vertical direction (lower side in the drawing) and on the upper side in the vertical direction (upper side in the drawing). It is divided into a downstream drying chamber 12b. A number of through holes are formed in the upstream gas dispersion plate 6a and the downstream gas dispersion plate 6b.

  The fluidized bed drying apparatus 1 includes a fluidized steam supply unit 21 that supplies fluidized steam to the upstream wind chamber 11a and the downstream wind chamber 11b, and a gas that supplies non-condensable gas such as nitrogen to the upstream wind chamber 11a. And a supply unit 25. The fluidized steam supply unit 21 is connected to the upstream wind chamber 11a and the downstream wind chamber 11b and supplies fluidized steam. On the other hand, the gas supply unit 25 is connected to a supply line that connects the fluidized vapor supply unit 21 and the upstream wind chamber 11a, and supplies the non-condensable gas together with the fluidized vapor as the fluidized gas. For this reason, since fluidized gas is introduced into the upstream drying chamber 12a via the upstream wind chamber 11a, the dew point temperature in the upstream drying chamber 12a can be made lower than 100 ° C. Become. On the other hand, since fluidized steam is introduced into the downstream drying chamber 12b via the downstream wind chamber 11b, the dew point temperature in the downstream drying chamber 12b needs to be around 100 ° C. The non-condensable gas supplied from the gas supply unit 25 may be supplied from, for example, an external non-condensable gas supply device or may be supplied with exhaust gas discharged from a gas turbine or a boiler. Good.

  In the upstream drying chamber 12a of the upstream drying furnace 5a, an upstream lignite inlet 31 into which lignite is charged, an upstream dry coal outlet 34 that discharges dry coal obtained by heating and drying lignite, fluidized gas, and A gas discharge port 35 for discharging generated steam generated during drying and an upstream heat transfer tube (upstream heat transfer member) 33 for heating lignite are provided.

  The upstream lignite charging port 31 is formed at the upper part of one end side (the left side in the drawing) of the upstream drying chamber 12a. A coal feeder 111 is connected to the upstream lignite inlet 31, and the lignite supplied from the coal feeder 111 is supplied to the upstream drying chamber 12 a.

  The upstream dry coal discharge port 34 is formed in the lower part on the other end side (the right side in the drawing) of the upstream drying chamber 12a. From the upstream dry coal discharge port 34, the brown coal initially dried in the upstream drying chamber 12a is discharged as dry coal, and the discharged dry coal is supplied toward the downstream drying chamber 12b.

  The gas discharge port 35 is formed in the upper part on the other end side of the upstream drying chamber 12a. The gas discharge port 35 discharges generated steam generated by heating the lignite together with the fluidizing gas supplied to the upstream drying chamber 12a during the initial drying of the lignite. Note that the fluidized gas and generated steam discharged from the gas discharge port 35 are effectively utilized by being supplied to a trace tube or the like that keeps the object to be kept warm.

  The upstream heat transfer tube 33 is configured in a panel shape, and is provided inside the fluidized bed 3 formed by the flow of lignite in the upstream drying chamber 12a. The upstream side heat transfer tube 33 is connected to the outflow side of a downstream side heat transfer tube (downstream side heat transfer member) 43, which will be described later, and steam as a heat medium (for drying, which will be described later) that circulates the downstream side heat transfer tube 43 in the tube. Steam) is supplied.

  In the downstream drying chamber 12b of the downstream drying furnace 5b, a downstream lignite inlet 41 into which the initially dried lignite is charged, a downstream dry coal outlet 44 that discharges the dried coal by heating and drying the lignite, A steam outlet 45 for discharging fluidized steam and generated steam generated during drying, and a downstream heat transfer pipe 43 for heating lignite are provided.

  The downstream lignite inlet 41 is formed at the upper part of one end side (the left side in the figure) of the downstream drying chamber 12b. An upstream dry coal discharge port 34 is connected to the downstream lignite input port 41 via a fuel supply line L1. A rotary feeder 48 is interposed in the fuel supply line L1. The rotary feeder 48 operates to supply the lignite discharged from the upstream dry coal discharge port 34 toward the downstream lignite input port 41. For this reason, the lignite supplied from the rotary feeder 48 is supplied to the downstream drying chamber 12b through the downstream lignite inlet 41.

  The downstream dry coal discharge port 44 is formed in the lower part on the other end side (right side in the drawing) of the downstream drying chamber 12b. From the downstream dry coal discharge port 44, the lignite that has been dried late in the downstream drying chamber 12b is discharged as dry coal, and the discharged dry coal is supplied to the cooler 131 described above.

  The steam outlet 45 is formed in the upper part on the other end side of the downstream drying chamber 12b. The steam discharge port 45 discharges generated steam generated by heating the lignite together with the fluidized steam supplied to the downstream drying chamber 12b during the latter drying of the lignite. The fluidized steam and generated steam discharged from the steam discharge port 45 are supplied to the dust collector 139 and then supplied to the steam compressor 135.

  The downstream heat transfer tube 43 is configured in a panel shape, and is provided inside the fluidized bed 3 formed by the flow of lignite in the downstream drying chamber 12b. The downstream side heat transfer pipe 43 is connected to the outflow side of the steam compressor 135, and the steam compressed by the steam compressor 135 is supplied into the pipe as drying steam.

  For this reason, when the drying steam is supplied from the steam compressor 135, the supplied drying steam flows into the downstream heat transfer tube 43. When the drying steam is supplied into the pipe, the downstream heat transfer pipe 43 uses the latent heat of the drying steam to heat the lignite, thereby removing moisture in the lignite in the fluidized bed 3, The lignite in the downstream drying chamber 12b is dried late. Thereafter, the drying steam that has flowed through the downstream heat transfer tube 43 flows into the upstream heat transfer tube 33. When the drying steam is supplied into the pipe, the upstream heat transfer pipe 33 uses the latent heat of the drying steam to initially dry the lignite in the upstream drying chamber 12a. Thereafter, the drying steam used for the initial drying is discharged to the outside of the upstream drying chamber 12a.

  Further, a gas-liquid separator 51 is provided between the upstream heat transfer tube 33 and the downstream heat transfer tube 43. The gas-liquid separator 51 is provided outside the drying furnace 5 and is connected to the upstream heat transfer tube 33 and the downstream heat transfer tube 43. For this reason, a part on the outflow side of the downstream heat transfer tube 43 and a part on the inflow side of the upstream heat transfer tube 33 connected to the gas-liquid separator 51 are arranged outside the drying furnace 5. Drying steam flows into the gas-liquid separator 51 from the downstream heat transfer tube 43. The gas-liquid separator 51 separates the drying steam flowing in from the downstream heat transfer tube 43 into a liquid phase and a gas phase, and supplies the drying vapor in the gas phase to the upstream heat transfer tube 33 while The dried drying steam is discharged as condensed water.

  The fluidized steam supply unit 21 supplies fluidized steam to the upstream wind chamber 11a and the downstream wind chamber 11b (fluidized steam supply step). The gas supply unit 25 mixes the non-condensable gas with the fluidized steam supplied by the fluidized steam supply unit 21 and supplies the mixed gas to the upstream wind chamber 11a as the fluidized gas (fluidized gas supply step). The lignite supplied to the upstream drying chamber 12a via the upstream lignite inlet 31 is fluidized by the fluidized gas supplied via the upstream gas dispersion plate 6a, so that the upstream drying chamber 12a has a fluidized bed. 3 and a free board portion F is formed above the fluidized bed 3. The fluidized bed 3 formed in the upstream drying chamber 12a has a flowing direction from one end side to the other end side of the upstream drying chamber 12a. The lignite that has become the fluidized bed 3 is heated by the upstream heat transfer tube 33, so that the moisture contained in the lignite becomes generated steam and is discharged from the gas discharge port 35 together with the fluidizing gas. The lignite heated by the upstream heat transfer tube 33 is initially dried by removing moisture. The initially dried lignite is discharged from the upstream dry coal discharge port 34.

  The lignite discharged from the upstream dry coal discharge port 34 is supplied to the downstream drying chamber 12b through the fuel supply line L1 by the operating rotary feeder 48 and the downstream lignite input port 41. The lignite supplied to the downstream drying chamber 12b flows by fluidized steam supplied via the downstream gas dispersion plate 6b, thereby forming the fluidized bed 3 in the downstream drying chamber 12b and the fluidized bed 3 A free board portion F is formed above the. The fluidized bed 3 formed in the downstream drying chamber 12b has a flowing direction from one end side to the other end side of the downstream drying chamber 12b. The lignite that has become the fluidized bed 3 is heated by the downstream heat transfer tube 43 so that the moisture contained in the lignite becomes generated steam and is discharged from the steam outlet 45 together with the fluidized steam (steam discharge process). . The lignite heated by the downstream heat transfer tube 43 is dried later by removing moisture. The late-dried lignite is discharged from the downstream dry coal discharge port 44.

  The discharged steam discharged from the steam discharge port 45 is supplied to the steam compressor 135 after the pulverized coal is collected by the dust collector 139, and is heated by being compressed by the steam compressor 135 (steam Compression process). The compressed steam is supplied to the downstream heat transfer tube 43 as drying steam and flows through the downstream heat transfer tube 43 (downstream steam supply step). Thereafter, the drying steam that has flowed through the downstream heat transfer tube 43 flows into the gas-liquid separator 51. The gas-liquid separator 51 gas-liquid separates the drying vapor into a liquid phase and a gas phase, and discharges the vapor that has become a liquid phase as condensed water, while the drying vapor that has become a gas phase is transmitted upstream. Supply to the heat pipe 33 (upstream steam supply step). Then, the drying steam supplied to the upstream heat transfer tube 33 flows through the upstream heat transfer tube 33 and is then discharged to the outside of the drying furnace 5. Therefore, the heat transfer tubes 33 and 43 circulate the drying steam from the downstream side in the flow direction of the lignite toward the upstream side.

  Next, with reference to FIG. 3 and FIG. 4, the quality of the drying steam flowing through the upstream heat transfer pipe 33 and the downstream heat transfer pipe 43 of the fluidized bed drying apparatus 1 will be described. 3 and 4 are graphs relating to the quality of the drying steam in the fluidized bed drying apparatus according to the first embodiment. In the graphs shown in FIGS. 3 and 4, the horizontal axis represents the quality of the drying steam, and the vertical axis represents the temperature of the drying steam. The quality is the ratio of vapor in the vapor phase to the total amount of vapor, and the lower the quality, the smaller the ratio of vapor in the vapor phase and the higher the ratio of liquid vapor.

  For this reason, since the drying steam compressed by the steam compressor 135 flows through the downstream heat transfer pipe 43 and then flows through the upstream heat transfer pipe 33, the high-quality drying steam flows through the downstream heat transfer pipe 43. On the inflow side, low-quality drying steam becomes the outflow side of the upstream heat transfer tube 33.

  In the graphs of FIGS. 3 and 4, the mixing ratio of the non-condensable gas contained in the atmosphere in the downstream drying furnace 5b is 5 wt%. At this time, the pressure of the atmosphere in the drying furnace 5 is 0.1 MPa. For this reason, the dew point temperature T1 in the downstream drying furnace 5b is around 100 ° C. On the other hand, in the graph of FIG. 3, the mixing rate of the non-condensable gas contained in the atmosphere in the upstream drying furnace 5a is 50 wt%. At this time, the pressure of the atmosphere in the upstream drying furnace 5a is also 0.1 MPa. For this reason, the dew point temperature T2 in the upstream drying furnace 5a is around 86 ° C. Moreover, in the graph of FIG. 4, the mixing rate of the noncondensable gas contained in the atmosphere in the upstream drying furnace 5a is 75 wt%. At this time, the pressure of the atmosphere in the upstream drying furnace 5a is also 0.1 MPa. For this reason, the dew point temperature T2 in the upstream drying furnace 5a is around 72 ° C.

  3 and 4, the steam discharged from the downstream drying furnace 5b is compressed by the steam compressor 135 and supplied to the downstream heat transfer pipe 43, so that the upstream heat transfer pipe 33 and the downstream heat transfer pipe 43 are compressed. The mixing rate of the non-condensable gas contained in the drying steam flowing through the heat pipe 43 is 5 wt%. At this time, the pressures in the upstream heat transfer tube 33 and the downstream heat transfer tube 43 through which the drying steam flows are each 0.49 MPa.

  As shown in FIG. 3 and FIG. 4, in the fluidized bed drying apparatus 1, since the non-condensable gas is mixed in the drying steam, when the quality of the drying steam is reduced, the drying steam is in the gas phase. The proportion of steam is reduced. That is, the ratio of the non-condensable gas in the vapor phase of the drying vapor is increased. For this reason, since it becomes difficult to collect latent heat from the low-quality drying steam, when the quality of the drying steam becomes smaller than 0.2, the temperature T3 of the drying steam rapidly decreases.

  Here, in the downstream drying furnace 5b, since the dew point temperature T1 in the furnace is around 100 ° C., the temperature T3 of the drying steam supplied to the downstream heat transfer tube 43 needs to be 100 ° C. or higher. The temperature difference between the temperature T1 and the temperature T3 of the drying steam (downstream heat transfer tube 43) is a predetermined temperature difference ΔT1. On the other hand, in the upstream drying furnace 5a, since the dew point temperature T2 in the furnace is around 86 ° C. or around 72 ° C., the temperature T3 of the drying steam supplied to the upstream heat transfer tube 33 is applied to the downstream heat transfer tube 43. Even if the temperature is lower than the temperature T3 of the supplied drying steam, the temperature difference between the dew point temperature T2 and the temperature T3 of the drying steam (upstream heat transfer pipe 33) becomes a predetermined temperature difference ΔT2. Thus, since the temperature difference ΔT2 can be secured, the lignite can be preferably initially dried by the upstream heat transfer pipe 33, and since the temperature difference ΔT1 can be secured, the lignite can be suitably fed by the downstream heat transfer pipe 43. Can be dried.

  As described above, according to the configuration of the first embodiment, in the upstream drying chamber 12a, the temperature difference ΔT2 between the dew point temperature T2 and the drying steam temperature T3 can be suitably secured. Thereby, the lignite flowing through the upstream drying chamber 12a can be initially dried with drying steam having a higher proportion of non-condensable gas in the gas phase than the downstream drying chamber 12b. On the other hand, in the downstream drying chamber 12b, a temperature difference ΔT1 between the dew point temperature T1 and the drying steam temperature T3 can be suitably secured. Thereby, the lignite flowing in the downstream drying chamber 12b can be late-dried with the drying steam having a lower proportion of non-condensable gas in the gas phase than the upstream drying chamber 12a. Therefore, by supplying a fluidizing gas containing non-condensable gas into the upstream drying chamber 12a, lignite is suitable even for low-temperature drying steam with a large proportion of non-condensable gas in the gas phase. Therefore, the steam can be used effectively, and the latent heat of the steam can be efficiently recovered.

  In addition, according to the configuration of Example 1, the drying furnace 5 can be divided into the upstream drying furnace 5a and the downstream drying furnace 5b, so that the fluidized gas supplied into the upstream drying furnace 5a is: Mixing in the downstream drying furnace 5b can be suppressed.

  In addition, according to the configuration of the first embodiment, the drying supplied to the upstream heat transfer tube 33 is performed by discharging, as condensed water, the liquid-phase drying steam that has passed through the downstream heat transfer tube 43 by the gas-liquid separator 51. It is possible to increase the proportion of the vapor of the industrial steam. That is, the gas-liquid separator 51 can convert a low-quality vapor having a high proportion of non-condensable gas in the gas phase into a high-quality vapor having a high proportion of non-condensable gas in the gas phase. Thereby, since the inflow of the liquid phase steam (condensed water) can be suppressed in the upstream heat transfer tube 33, the formation of a liquid film inside the upstream heat transfer tube 33 can be suppressed, and the heat transfer coefficient can be improved. Can be achieved. In addition, in Example 1, although the gas-liquid separator 51 was provided, the structure which abbreviate | omitted may be sufficient.

  In Example 1, the brown coal initially dried in the upstream drying chamber 12a was supplied to the downstream drying chamber 12b by the rotary feeder 48, but the present invention is not limited to this configuration. For example, the lignite initially dried in the upstream drying chamber 12a may be supplied to the downstream drying chamber 12b by a screw feeder. That is, a connecting pipe that connects the upstream drying chamber 12a and the downstream drying chamber 12b is provided, a screw feeder is provided in the connecting pipe, and the screw feeder is operated, so that the upstream drying chamber 12a and the downstream drying chamber 12b are operated. It may be configured to supply lignite.

  Next, with reference to FIG. 5, the fluidized bed drying apparatus 200 which concerns on Example 2 is demonstrated. FIG. 5 is a schematic configuration diagram schematically illustrating the fluidized bed drying apparatus according to the second embodiment. In the second embodiment, parts that are different from the first embodiment will be described in order to avoid duplicated descriptions, and parts that have the same configuration as the first embodiment are denoted by the same reference numerals. The fluidized bed drying apparatus 1 according to the first embodiment is configured by dividing the drying furnace 5 into the upstream drying furnace 5a and the downstream drying furnace 5b. However, in the fluidized bed drying apparatus 200 according to the second embodiment, a single unit is used. The drying furnace 5 is divided into an upstream drying chamber 12a and a downstream drying chamber 12b. Hereinafter, the fluidized bed drying apparatus 200 according to the second embodiment will be described.

  As shown in FIG. 5, the fluidized bed drying apparatus 200 has a single drying furnace 5. A gas dispersion plate 6 is provided inside the drying furnace 5. The gas distribution plate 6 includes a wind chamber 11a, 11b located on the lower side (lower side in the drawing) and a drying chamber 12a, 12b located on the upper side (upper side) in the vertical direction. It is divided into and.

  The fluidized bed drying apparatus 200 includes a drying chamber partition member 201 that partitions the drying chambers 12a and 12b, and an air chamber partition member 202 that partitions the air chambers 11a and 11b. The drying chamber partition member 201 divides the drying chambers 12a and 12b into an upstream drying chamber 12a and a downstream drying chamber 12b along the flow direction. The drying chamber partition member 201 is provided with a vertical upper end connected to the upper portion of the drying chamber 12 and a lower end spaced from the gas dispersion plate 6. For this reason, the brown coal initially dried in the upstream drying chamber 12 a is introduced into the downstream drying chamber 12 b through the gap formed by the drying chamber partition member 201. Therefore, in Example 2, the upstream dry coal discharge port 34 of Example 1 is abolished.

  The air chamber partition member 202 divides the air chambers 11a and 11b into an upstream air chamber 11a and a downstream air chamber 11b along the flow direction. The wind chamber partition member 202 has an upper end portion in the vertical direction connected to the upper portions of the wind chambers 11a and 11b, and a lower end portion connected to the lower portions of the wind chambers 11a and 11b.

  The fluidized bed drying apparatus 200 includes a fluidized steam supply unit 21 that supplies fluidized steam to the upstream wind chamber 11a and the downstream wind chamber 11b, and a supply that connects the fluidized steam supply unit 21 and the upstream wind chamber 11a. And a gas supply unit 25 connected to the line. The fluidized steam supply unit 21 and the gas supply unit 25 supply fluidized gas containing fluidized steam and non-condensable gas to the upstream wind chamber 11a and supply the downstream wind chamber 11b to the upstream wind chamber 11b, as in the first embodiment. Supply fluidized steam.

  The fluidized steam supply unit 21 supplies fluidized steam to the upstream wind chamber 11a and the downstream wind chamber 11b (fluidized steam supply step). The gas supply unit 25 mixes the non-condensable gas with the fluidized steam supplied by the fluidized steam supply unit 21 and supplies the mixed gas to the upstream wind chamber 11a as the fluidized gas (fluidized gas supply step). The lignite supplied to the upstream drying chamber 12a via the upstream lignite charging port 31 flows by the fluidized gas supplied via the gas dispersion plate 6, so that the fluidized bed 3 is formed in the upstream drying chamber 12a. At the same time, the free board portion F is formed above the fluidized bed 3. The flow direction of the fluidized bed 3 formed in the upstream drying chamber 12a is the direction from one end side of the drying furnace 5 to the other end side. The lignite that has become the fluidized bed 3 is heated by the upstream heat transfer tube 33, so that the moisture contained in the lignite becomes generated steam and is discharged from the gas discharge port 35 together with the fluidizing gas. The lignite heated by the upstream heat transfer tube 33 is initially dried by removing moisture. The brown coal initially dried in the upstream drying chamber 12a is introduced into the downstream drying chamber 12b through the gap formed by the drying chamber partition member 201.

  The lignite introduced from the upstream drying chamber 12a to the downstream drying chamber 12b flows by fluidized steam supplied through the gas dispersion plate 6, thereby forming the fluidized bed 3 in the downstream drying chamber 12b. The free board portion F is formed above the fluidized bed 3. The flow direction of the fluidized bed 3 formed in the downstream drying chamber 12b is the direction from one end side to the other end side of the drying furnace 5, as in the upstream drying chamber 12a. The lignite that has become the fluidized bed 3 is heated by the downstream heat transfer tube 43 so that the moisture contained in the lignite becomes generated steam and is discharged from the steam outlet 45 together with the fluidized steam (steam discharge process). . The lignite heated by the downstream heat transfer tube 43 is dried later by removing moisture. The late-dried lignite is discharged from the downstream dry coal discharge port 44.

  The discharged steam discharged from the steam discharge port 45 is supplied to the steam compressor 135 after the pulverized coal is collected by the dust collector 139, and is heated by being compressed by the steam compressor 135 (steam Compression process). The compressed steam is supplied to the downstream heat transfer tube 43 as drying steam and flows through the downstream heat transfer tube 43 (downstream steam supply step). Thereafter, the drying steam that has flowed through the downstream heat transfer tube 43 flows into the gas-liquid separator 51. The gas-liquid separator 51 gas-liquid separates the drying vapor into a liquid phase and a gas phase, and discharges the vapor that has become a liquid phase as condensed water, while the drying vapor that has become a gas phase is transmitted upstream. Supply to the heat pipe 33 (upstream steam supply step). Then, the drying steam supplied to the upstream heat transfer tube 33 flows through the upstream heat transfer tube 33 and is then discharged to the outside of the drying furnace 5. Therefore, the heat transfer pipe 33 circulates the drying steam from the downstream side in the flow direction of the lignite toward the upstream side.

  As described above, also in the configuration of the second embodiment, in the upstream drying chamber 12a, the temperature difference ΔT2 between the dew point temperature T2 and the drying steam temperature T3 can be suitably secured. Thereby, the lignite flowing through the upstream drying chamber 12a can be initially dried with drying steam having a higher proportion of non-condensable gas in the gas phase than the downstream drying chamber 12b. On the other hand, in the downstream drying chamber 12b, a temperature difference ΔT1 between the dew point temperature T1 and the drying steam temperature T3 can be suitably secured. Thereby, the lignite flowing in the downstream drying chamber 12b can be late-dried with the drying steam having a lower proportion of non-condensable gas in the gas phase than the upstream drying chamber 12a. Therefore, by supplying a fluidizing gas containing non-condensable gas into the upstream drying chamber 12a, lignite is suitable even for low-temperature drying steam with a large proportion of non-condensable gas in the gas phase. Therefore, the steam can be used effectively, and the latent heat of the steam can be efficiently recovered.

  Moreover, according to the structure of Example 2, since it can comprise with the single drying furnace 5 by using the drying chamber partition member 201, it can make the structure of the fluidized-bed drying apparatus 200 simple. it can.

  In addition, this invention is not limited to the structure of Example 1 and 2 mentioned above, It can also implement as a structure of the modifications 1 thru | or 6 mentioned below. Hereinafter, modifications 1 to 6 will be described. In addition, although the structure of the modifications 1 thru | or 6 is demonstrated applying to Example 1, it is also possible to apply to Example 2. FIG. FIG. 6 is a schematic configuration diagram schematically illustrating a fluidized bed drying apparatus according to the first modification. FIG. 7 is a schematic configuration diagram schematically illustrating a fluidized bed drying apparatus according to the second modification. FIG. 8 is a schematic configuration diagram schematically showing a fluidized bed drying apparatus according to Modification 3. FIG. 9 is a schematic configuration diagram schematically illustrating a fluidized bed drying apparatus according to Modification 4. FIG. 10 is a schematic configuration diagram schematically illustrating a fluidized bed drying apparatus according to Modification 5. FIG. 11 is a schematic configuration diagram schematically illustrating a fluidized bed drying apparatus according to Modification 6.

  As shown in FIG. 2, in the fluidized bed drying apparatus 1 of Example 1, the steam discharged from the steam discharge port 45 formed in the upper part on the other end side of the downstream drying chamber 12 b passes through the dust collector 139. The steam compressed by the compressor 135 is supplied to the downstream heat transfer tube 43 as drying steam. However, as shown in FIG. 6, in the fluidized bed drying apparatus 1 of the first modification, the steam discharged from the downstream drying chamber 12 b is compressed by the compressor 135 via the dust collector 139 and then the downstream heat transfer tube. A part of the drying steam supplied to 43 can be extracted and supplied to the downstream wind box 11b as fluidized steam. By setting it as such a structure, in the fluidized bed drying apparatus 1 of the modification 1, the amount of vapor | steam supplied from the outside can be decreased. Further, as shown in FIG. 7, in the fluidized bed drying apparatus 1 of the second modified example, the downstream air is supplied to the supply line through which the steam discharged from the downstream drying chamber 12 b is supplied to the compressor 135 via the dust collector 139. A supply line for supplying to the chamber 11b is connected. A booster blower 210 may be provided in a supply line that supplies the downstream wind chamber 11b, and steam compressed by the booster blower 210 may be supplied to the downstream wind chamber 11b. With such a configuration, in the fluidized bed drying apparatus 1 of the second modification, the power of the compressor 135 can be reduced.

  As shown in FIG. 8, in the fluidized bed drying apparatus 1 of Modification 3, the steam discharged from the downstream drying chamber 12 b is compressed by the compressor 135 via the dust collector 139 and then the downstream heat transfer tube 43. A part of the drying steam supplied to the air can be extracted and fed into the upstream wind chamber 11a and the downstream wind chamber 11b as fluidized steam. By setting it as such a structure, in the fluidized bed drying apparatus 1 of the modification 3, the amount of vapor | steam supplied from the outside can be decreased. As shown in FIG. 9, in the fluidized bed drying apparatus 1 of the modified example 4, the downstream wind is supplied to the supply line through which the steam discharged from the downstream drying chamber 12 b is supplied to the compressor 135 via the dust collector 139. A supply line to be supplied to the chamber 11b is connected, and a supply line to be supplied to the upstream wind chamber 11a is connected to a supply line to be supplied to the downstream wind chamber 11b. Further, a booster blower 210 may be provided in a supply line that supplies the downstream wind chamber 11b, and steam compressed by the booster blower 210 may be supplied to the downstream wind chamber 11b and the upstream wind chamber 11a. By setting it as such a structure, in the fluidized bed drying apparatus 1 of the modification 4, the motive power of the compressor 135 can be reduced.

  Further, as shown in FIG. 10, in the fluidized bed drying apparatus 1 of the modified example 5, in addition to the configuration of the modified example 1, the gas discharge port 35 formed at the upper part on the other end side of the upstream drying chamber 12a, A circulation line for connecting the supply line for supplying the fluidized steam from the fluidized steam supply unit 21 to the upstream wind chamber 11a is provided, and the booster blower 211 is provided in the circulation line. Then, the fluidized gas and the generated steam with a high proportion of the non-condensable gas in the gas phase discharged from the gas discharge port 35 of the upstream drying chamber 12 a are boosted together with the fluidized steam from the fluidized steam supply unit 21. The air is supplied to the upstream wind chamber 11a by the blower 211. By setting it as such a structure, in the fluidized-bed drying apparatus 1 of the modification 5, it is not necessary to provide the gas supply part 22, and it leads to the simplification of an apparatus and cost reduction. Moreover, as shown in FIG. 11, in the fluidized bed drying apparatus 1 of the modification 6, the structure of the modification 2 and the structure of the modification 5 are combined. That is, in the fluidized bed drying apparatus 1 of the modified example 6, in addition to the configuration of the modified example 5, the steam discharged from the downstream drying chamber 12b is supplied downstream to the compressor 135 via the dust collector 139. A supply line for supplying to the wind chamber 11b is connected. A booster blower 210 may be provided in a supply line that supplies the downstream wind chamber 11b, and steam compressed by the booster blower 210 may be supplied to the downstream wind chamber 11b. With such a configuration, in the fluidized bed drying apparatus 1 of Modification 6, the power of the compressor 135 can be reduced.

DESCRIPTION OF SYMBOLS 1 Fluidized bed drying apparatus 3 Fluidized bed 5 Drying furnace 5a Upstream drying furnace 5b Downstream drying furnace 6a Upstream gas dispersion plate 6b Downstream gas dispersion plate 11a Upstream wind chamber 11b Downstream wind chamber 12a Upstream drying chamber 12b Downstream Side drying chamber 21 Fluidized steam supply unit 25 Gas supply unit 31 Upstream lignite input port 33 Upstream heat transfer pipe 34 Upstream dry coal discharge port 35 Gas discharge port 41 Downstream lignite input port 43 Downstream heat transfer tube 44 Downstream drying Charcoal outlet 45 Steam outlet 48 Rotary feeder 51 Gas-liquid separator 200 Fluidized bed dryer 201 Drying chamber partition member 202 Air chamber partition member F Free board section L1 Fuel supply line

Claims (6)

A drying furnace in which wet fuel is supplied;
Fluidizing steam is supplied to the drying furnace, and the wet fuel is fluidized to form a fluidized steam supply section in the drying furnace;
A heat transfer member provided in the drying furnace for heating the supplied wet fuel;
A compressor that compresses the steam discharged from the drying furnace and supplies the compressed steam toward the heat transfer member,
The drying furnace has an upstream drying chamber provided on the upstream side in the flow direction of the wet fuel, and a downstream drying chamber provided on the downstream side of the upstream drying chamber,
The heat transfer member includes an upstream heat transfer member provided in the upstream drying chamber and a downstream heat transfer member provided in the downstream drying chamber, and steam supplied from the compressor is And after passing through the downstream heat transfer member, provided to flow through the upstream heat transfer member,
The compressor compresses the steam discharged from the downstream drying chamber;
The fluidized steam supply unit supplies the fluidized steam to the upstream drying chamber and the downstream drying chamber, and has a higher content of non-condensable gas than the downstream drying chamber. Is supplied to the upstream drying chamber.   The fluidized bed according to claim 1, wherein the drying furnace is divided into an upstream drying furnace that forms the upstream drying chamber and a downstream drying furnace that forms the downstream drying chamber. Drying equipment.   The fluidized bed drying apparatus according to claim 1, wherein the drying furnace includes a partition plate that divides an interior into the upstream drying chamber and the downstream drying chamber.   A gas-liquid separation device that gas-liquid separates the steam flowing in from the downstream heat transfer member and supplies the vapor in the vapor phase to the upstream heat transfer member, while discharging the liquid vapor as condensed water, The fluidized bed drying apparatus according to any one of claims 1 to 3, further comprising: A fluidized bed drying apparatus according to any one of claims 1 to 4,
A gasification furnace that processes the wet fuel after drying supplied from the fluidized bed drying device and converts it into gasification gas;
A gas turbine operated using the gasified gas as fuel;
A steam turbine operated by steam generated by an exhaust heat recovery boiler that introduces turbine exhaust gas from the gas turbine;
A gasification combined power generation facility comprising the gas turbine and a generator connected to the steam turbine. A drying method of drying the wet fuel by heating the wet fuel with a heat transfer member provided in the dry furnace while flowing the wet fuel supplied into the dry furnace with fluidized steam. ,
The drying furnace has an upstream drying chamber provided on the upstream side in the flow direction of the wet fuel, and a downstream drying chamber provided on the downstream side of the upstream drying chamber,
The heat transfer member has an upstream heat transfer member provided in the upstream drying chamber, and a downstream heat transfer member provided in the downstream drying chamber,
A fluidized steam supply step of supplying the fluidized steam to the upstream drying chamber and the downstream drying chamber;
A fluidized gas supply step of supplying fluidized steam having a higher content of non-condensable gas than the downstream drying chamber to the upstream drying chamber as a fluidized gas;
A steam discharge step for discharging steam generated during drying of the wet fuel from the downstream drying chamber;
A vapor compression step of compressing the vapor discharged in the vapor discharge step;
A downstream steam supply step for supplying the steam compressed in the vapor compression step to the downstream heat transfer member;
A drying method comprising: an upstream steam supply step for supplying steam flowing through the downstream heat transfer member to the upstream heat transfer member.

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