WO2012141217A1 - Fluidized bed drying apparatus - Google Patents

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

Fluidized bed dryer

The present invention relates to a fluidized bed drying apparatus that dries while flowing wet fuel such as lignite.

Conventionally, as such a fluidized bed drying apparatus, a drying furnace (main body), a partition plate that divides the inside of the drying furnace into a supply chamber and a drying classification chamber, a supply chamber, a drying classification chamber, and a lower part via a gas dispersion plate There are known chamber chambers (wind boxes) provided (see, for example, Patent Document 1). In this fluidized bed drying apparatus, by adjusting the flow rate of the fluidizing gas supplied to the supply chamber and the drying classification chamber, agglomeration of wet fuel supplied to the drying furnace is suppressed, and the flow in the drying furnace is controlled. Going stable.

JP 2008-128524 A

By the way, the fluidized gas used in the fluidized bed drying apparatus is heated to dry the wet fuel. At this time, in order to efficiently recover the latent heat of the fluidized gas (exhaust gas) discharged after drying. In some cases, a condensable gas such as steam is used as the fluidizing gas. When steam is used as the fluidizing gas, the wet fuel can be suitably dried by adjusting the flow rate of the fluidizing gas as in a conventional fluidized bed drying apparatus. However, fluidized gas such as steam needs to have a higher temperature than non-condensable gas in order to suppress condensation in the piping and drying furnace. For this reason, it has been difficult to achieve further stable operation and efficiency of the fluidized bed drying apparatus using only condensable gas.

Accordingly, an object of the present invention is to provide a fluidized bed drying apparatus capable of improving the efficiency of drying wet fuel, suppressing the poor flow of wet fuel, and suitably drying the wet fuel. .

The fluidized bed drying apparatus of the present invention is a fluidized bed drying apparatus capable of drying a wet fuel while forming a fluidized bed by flowing the wet fuel with a fluidized gas. The chamber chamber is divided into a chamber chamber into which fluidized gas flows and a drying chamber to which wet fuel is supplied, and a gas ejection section for allowing the fluidized gas to flow into the drying chamber from the chamber chamber. A plurality of first fluidized gases having a low vapor concentration flows into a chamber chamber provided in the flow direction and located upstream of the flow direction, and the first chamber gas located downstream of the flow direction contains the first fluidization gas. The second fluidizing gas having a higher vapor concentration flows in compared with the fluidizing gas.

According to this configuration, the wet fuel on the upstream side in the flow direction in the early stage of drying can be dried using the first fluidized gas having a low vapor concentration, and the downstream side in the flow direction in the later stage of drying. The wet fuel can be dried using a second fluidized gas having a high vapor concentration. As a result, since the vapor concentration of the first fluidizing gas is low, the wet fuel can be suitably dried while the temperature of the first fluidizing gas is lowered as compared with the second fluidizing gas. The efficiency of fuel drying can be increased, and the wet fuel can be suitably dried. In addition, as a gas ejection part, what formed many through-holes in the board (gas dispersion | distribution board), or what formed many gas nozzles in the board is applicable.

In this case, the heat medium provided in the drying chamber and flowing inside the heat transfer tube flows from the downstream side to the upstream side in the flow direction, the gas discharge port for discharging the exhaust gas generated in the drying chamber, the gas exhaust A first heat medium supply line connecting the outlet and the inflow side of the heat transfer tube, a compressor interposed in the first heat medium supply line, compressing the exhaust gas, and supplying the heat transfer tube as a heat medium; Is preferably further provided.

According to this configuration, the exhaust gas discharged from the drying chamber through the gas discharge port can be used as a heat medium for the heat transfer tube. Can be further improved.

In this case, the first fluidizing gas supply line connecting the outflow side of the heat transfer tube and the chamber chamber located upstream in the flow direction, the first heat medium supply line, and the chamber located downstream in the flow direction It is preferable to further include a second fluidizing gas supply line connecting the chambers.

According to this configuration, since the heat medium of the heat transfer tube can be used as the first fluidizing gas, the efficiency of drying the wet fuel can be further increased by the amount that the heat medium can be effectively used. Further, since the exhaust gas flowing through the first heat medium supply line can be used as the second fluidizing gas, the efficiency of drying the wet fuel can be further improved by the amount that the latent heat of the exhaust gas can be effectively used.

In this case, it is preferable to further include a first gas-liquid separator interposed in the first fluidizing gas supply line and capable of separating the condensate contained in the heat medium discharged from the heat transfer tube.

According to this configuration, the first gas-liquid separator separates the condensate contained in the heat medium discharged from the heat transfer tube, and uses the heat medium from which the condensate is separated as the first fluidizing gas. Can do. Thereby, since the 1st fluidization gas after condensate separation becomes a thing with low vapor concentration, it can be conveniently used as the 1st fluidization gas.

In this case, it is preferable that a first partition member for dividing the drying chamber into a plurality of chambers is further provided according to the plurality of chamber chambers, and the heat transfer tubes are respectively provided according to the plurality of drying chambers.

According to this configuration, after the wet fuel is dried in the drying chamber into which the first fluidizing gas flows, the wet fuel can be dried in the drying chamber into which the second fluidizing gas flows. For this reason, it is possible to suppress the wet fuel on the upstream side in the flow direction from moving to the downstream side in the flow direction in an undried state, and the wet fuel can be suitably dried.

In this case, a temperature detection sensor provided in a plurality of drying chambers, a flow rate adjustment valve capable of adjusting the flow rate of the second fluidizing gas, and a control device that controls the flow rate adjustment valve based on the temperature detected by the temperature detection sensor And the control device controls the flow rate adjustment valve so that the temperature of the drying chamber located downstream in the flow direction is higher than that of the drying chamber located upstream in the flow direction. Is preferred.

According to this configuration, by controlling the flow rate adjustment valve based on the temperature detected by the temperature detection sensor, the drying chamber located downstream in the flow direction compared to the drying chamber located upstream in the flow direction. The temperature can be increased. Thereby, since the latent heat of exhaust gas can be appropriately distributed as each fluidization gas, the latent heat of exhaust gas can be used efficiently.

In this case, the plurality of heat transfer tubes provided in the plurality of chambers are connected so that the heat medium flows from the heat transfer tube located on the downstream side in the flow direction to the heat transfer tube located on the upstream side in the flow direction. Preferably it is.

According to this configuration, the temperature of the heat transfer tube can be increased from the upstream side to the downstream side in the flow direction. Thereby, the wet fuel can be suitably dried without condensing the vapor contained in the first fluidizing gas and the second fluidizing gas.

In this case, the second gas-liquid separation is provided at the connection portion between the heat transfer tube located on the downstream side in the flow direction and the heat transfer tube located on the upstream side in the flow direction, and can separate the condensate contained in the heat medium. A heater capable of heating the first fluidizing gas, a second heating medium supply line for feeding the condensate separated by the second gas-liquid separator to the heater as a heating medium of the heater, Is preferably further provided.

According to this configuration, as the heating medium for the heater that heats the first fluidizing gas, the condensate in the heating medium separated by the second gas-liquid separator at the connection portion of the heat transfer tube can be used. Since the condensate can be effectively used, it is possible to further improve the efficiency of drying the wet fuel.

In this case, an extraction line for extracting the exhaust gas from the first heat medium supply line is further provided, and the first heat medium supply line connects the gas discharge port to the inflow side of the heat transfer pipe located downstream, The line connects the first heat medium supply line and the inflow side of the heat transfer pipe located on the upstream side, and the compressor is downstream of the connection portion where the first heat medium supply line and the extraction line are connected. It is preferable that it is interposed in the 1st heating-medium supply line located in.

According to this configuration, since the exhaust gas flowing through the first heat medium supply line is extracted through the extraction line, the flow rate of the exhaust gas supplied to the compressor can be reduced. It can be reduced and driving efficiency can be improved.

In this case, the apparatus further includes a second partition member that is provided in the drying furnace and that divides the free board portion positioned above the fluidized bed formed in the plurality of drying chambers into a plurality according to the plurality of drying chambers. Is preferred.

According to this configuration, the exhaust gas discharged from the drying chamber located upstream in the flow direction and the exhaust gas discharged from the drying chamber located downstream in the flow direction are mixed, whereby the exhaust gas is Condensation can be suppressed.

According to the fluidized bed drying apparatus of the present invention, the wet fuel on the upstream side in the flow direction is dried using the first fluidized gas having a low vapor concentration, and the wet fuel on the downstream side in the flow direction is high in the vapor concentration. By drying using the second fluidizing gas, the temperature of the first fluidizing gas can be lowered and the wet fuel can be suitably dried. Therefore, the efficiency of drying the wet fuel can be improved, and the wet The fuel can be suitably dried.

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 schematic configuration diagram schematically illustrating the fluidized bed drying apparatus according to the second embodiment. FIG. 4 is a schematic configuration diagram schematically illustrating the fluidized bed drying apparatus according to the third embodiment. FIG. 5 is a graph showing an enthalpy temperature curve of a heating medium flowing through a heat transfer tube and an enthalpy temperature curve of lignite during drying in a fluidized bed drying apparatus according to Example 3. FIG. 6 is a schematic configuration diagram schematically illustrating the fluidized bed drying apparatus according to the fourth embodiment. FIG. 7 is a graph showing an enthalpy temperature curve of a heat medium flowing through a heat transfer tube and an enthalpy temperature curve of lignite during drying in a fluidized bed drying apparatus according to Example 4.

Hereinafter, a fluidized bed drying apparatus 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 combined coal gasification combined power generation facility to which a fluidized bed drying apparatus according to Example 1 is applied. The coal gasification combined power generation facility (IGCC: Integrated Coal Gasification Combined Cycle) 100 to which the fluidized bed drying apparatus 1 of Example 1 is applied adopts an air combustion system that generates coal gas in a gasification furnace using air as an oxidizing agent. 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 a wet raw material supplied to the gasifier.

In Example 1, lignite was applied as a wet raw material, but low-grade coal including subbituminous coal or the like, peat such as sludge, etc. may be applied as long as the moisture content is high. Even charcoal is applicable. In addition, the wet raw material 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) reduced in weight.

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 included.

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.

Although the details will be described later, the fluidized bed drying device 1 removes moisture contained in the lignite by causing the lignite charged from the coal feeder 111 to flow with the fluidizing gas and heating and drying with the heat transfer tube 33. It is. 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 is separated by the dry coal electrostatic precipitator 134 is compressed by a steam compressor (compressor) 135 and then supplied to the heat transfer tube 33 of the fluidized bed drying apparatus 1 as a heat medium.

The pulverized coal machine 113 produces pulverized coal by pulverizing lignite (dry 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 gasification furnace 114 is supplied with the pulverized coal processed by the pulverized coal machine 113 and the 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 that combusts and gasifies coal, char, air (oxygen) supplied therein or water vapor as a gasifying agent, and produces carbon dioxide. A combustible gas (product gas, coal gas) containing carbon as a main component is generated, and a gasification reaction takes place using this combustible gas as a gasifying agent. 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 collection device 115 includes a dust collecting device 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 facility 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.

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

Here, the operation of the coal gasification combined cycle facility 100 of the first embodiment will be described.

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 is returned to the heat tube 33 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 subjected to gas purification by removing impurities such as sulfur compounds and nitrogen compounds in 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 discharged 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.

The fluidized bed drying apparatus 1 includes a drying furnace 5 in which lignite is supplied, and a gas dispersion plate (gas ejection part) 6 provided inside the drying furnace 5. The drying furnace 5 is formed in a rectangular box shape. The gas dispersion plate 6 includes a chamber chamber 11 (wind chamber) located on the lower side in the vertical direction (lower side in the drawing) and a drying chamber 12 located on the upper side in the vertical direction (upper side in the drawing). It is divided into. A number of through holes are formed in the gas dispersion plate 6, fluidizing gas such as steam and nitrogen is introduced into the chamber chamber 11, and lignite is supplied to the drying chamber 12. A gas exhaust port 13 for exhausting exhaust gas generated inside is provided at the top of the drying chamber 12. In the first embodiment, the gas dispersion plate 6 is used. However, the present invention is not limited to this configuration, and a configuration in which a number of gas nozzles are formed on the plate is also applicable.

Accordingly, the lignite supplied to the drying chamber 12 flows by the fluidized gas flowing from the chamber chamber 11 through the gas dispersion plate 6, thereby forming the fluidized bed 3 in the drying chamber 12. A free board portion F is formed above. And the brown coal which forms the fluidized bed 3 flows along the flow direction which goes from the edge part of one side (illustration left side) of the drying furnace 5 to the edge part of the other (right side illustration). The fluidized gas that has flowed into the drying chamber 12 becomes exhaust gas together with the steam generated during the drying of the lignite and is discharged from the gas outlet 13. The gas discharge port 13 is connected to a dust collector 139 including the dry coal cyclone 133 and the dry coal electric dust collector 134 described above.

The fluidized bed drying apparatus 1 includes a chamber partition plate 14 that partitions the chamber chamber 11, a lower partition plate (first partition member) 15 that partitions the fluidized bed 3 of the drying chamber 12, and a free board portion F of the drying chamber 12. An upper partition plate (second partition member) 16 is provided.

The chamber partition plate 14 divides the chamber chamber 11 into a plurality along the flow direction. Specifically, the chamber partition plate 14 is divided into a first chamber chamber 18 located on the upstream side in the flow direction and a second chamber chamber 19 located on the downstream side of the first chamber chamber 18. The first fluidizing gas flows into the first chamber chamber 18 and the second fluidizing gas flows into the second chamber chamber 19. The first fluidizing gas and the second fluidizing gas are a mixture of a condensable gas and a non-condensable gas. As the condensable gas, for example, a vapor is used as a non-condensable gas. Is, for example, air or nitrogen.

The first fluidizing gas flowing into the first chamber chamber 18 has a low vapor concentration, and the second fluidizing gas flowing into the second chamber chamber 19 has a high vapor concentration. That is, the first fluidizing gas has a lower vapor concentration than the second fluidizing gas. In other words, the second fluidizing gas has a vapor concentration that is lower than the first fluidizing gas. Is high. Further, the temperature of the first fluidizing gas is lower than that of the second fluidizing gas.

The lower partition plate 15 has a lower end connected to the gas dispersion plate 6 which is the bottom of the drying chamber 12, and an upper end located above the fluidized bed 3 formed in the drying chamber 12. The upper partition plate 16 is made of a heat insulating material or the like, the lower end portion thereof is located above the upper end portion of the lower partition plate 15, and the upper end portion thereof is located in the vicinity of the gas discharge port 13.

The drying chamber 12 is divided into a first drying chamber 21 and a second drying chamber 22 by a lower partition plate 15 and an upper partition plate 16. For this reason, lignite that forms the fluidized bed 3 of the first drying chamber 21 overflows the lower partition plate 15 and flows into the second drying chamber 22. The exhaust gas generated in the first drying chamber 21 is directed to the free board portion F of the first drying chamber 21, and the exhaust gas generated in the second drying chamber 22 is transferred to the free board portion F of the second drying chamber 22. Head. For this reason, the upper partition plate 16 suppresses mixing of the exhaust gas in the free board part F of the first drying chamber 21 and the exhaust gas in the free board part F of the second drying chamber 22.

The first drying chamber 21 is connected to a lignite supply port 31 for supplying lignite, the second drying chamber 22 is connected to a lignite discharge port 41, and the first drying chamber 21 and the second drying chamber 22 are connected to each other. Heat transfer tubes 33 for heating the brown coal are provided.

The lignite supply port 31 is connected to the first drying chamber 21 on the upstream side in the flow direction of the lignite, and serves as a supply port for supplying the lignite before drying to the first drying chamber 21. The crusher 123 described above is connected to the lignite supply port 31, and the pulverized lignite is supplied to the first drying chamber 21.

The lignite discharge port 41 is connected to the second drying chamber 22 on the downstream side in the flow direction of the lignite, and serves as a discharge port for discharging the dried lignite from the second drying chamber 22. The cooler 131 is connected to the lignite discharge port 41, and the dried lignite is discharged as dry coal.

The heat transfer tube 33 has a heat medium flowing therein, and the heat medium is configured to flow from the downstream side toward the upstream side in the flow direction. The heat transfer tube 33 has an upstream heat transfer tube 33 a provided inside the fluidized bed 3 of the first drying chamber 21 and a downstream heat transfer tube 33 b provided inside the fluidized bed 3 of the second drying chamber 22. is doing.

The inflow side of the downstream heat transfer tube 33b is connected to the gas discharge port 13 via the first heat medium supply line 51, and the outflow side is connected to the inflow side of the upstream heat transfer tube 33a. The first heat medium supply line 51 supplies exhaust gas from the gas discharge port 13 toward the downstream heat transfer pipe 33b as a heat medium. The first heat medium supply line 51 is provided with the dust collector 139, and the steam compressor 135 is provided downstream of the dust collector 139. Therefore, the exhaust gas discharged from the gas discharge port 13 is separated by dry dust particles by the dust collector 139, and the exhaust gas from which the dry coal is separated is compressed by the steam compressor 135. The compressed exhaust gas rises in temperature, becomes a heat medium, and flows into the downstream heat transfer tube 33b. Thereby, when the heat medium flows in, the downstream heat transfer pipe 33b heats the lignite forming the fluidized bed 3 in the second drying chamber 22, and evaporates moisture contained in the lignite.

The second fluidized gas supply line 52 is connected to the first heat medium supply line 51. The second fluidizing gas supply line 52 has one end connected to the first heat medium supply line 51 and the other end connected to the second chamber chamber 19. The second fluidizing gas supply line 52 supplies the exhaust gas compressed by the vapor compressor 135 to the second chamber 19 as the second fluidizing gas. A first flow rate adjusting valve 53 is interposed in the second fluidizing gas supply line 52, and the first flow rate adjusting valve 53 adjusts the flow rate of the second fluidizing gas flowing into the second chamber chamber 19. is doing.

The upstream heat transfer tube 33a has an inflow side connected to the downstream heat transfer tube 33b and an outflow side connected to a first fluidized gas supply line 55 described later. Thereby, when the heat medium supplied from the downstream heat transfer tube 33b flows into the upstream heat transfer tube 33a, the upstream heat transfer tube 33a heats the lignite that forms the fluidized bed 3 in the first drying chamber 21, The contained water is evaporated. At this time, since the heat medium flowing through the downstream heat transfer tube 33b is heat-exchanged in the second drying chamber 22, the temperature of the heat medium flowing through the upstream heat transfer tube 33a is the temperature of the heat medium flowing through the downstream heat transfer tube 33b. Lower than temperature.

Here, a second gas-liquid separator 56 is interposed at a connection portion between the upstream heat transfer tube 33a and the downstream heat transfer tube 33b. The 2nd gas-liquid separator 56 isolate | separates the condensed water (condensate) contained in the heat medium discharged | emitted from the downstream heat exchanger tube 33b. The second gas-liquid separator 56 supplies the condensed water separated from the heat medium to the second heat medium supply line 61 in which the second flow rate adjustment valve 54 is interposed. On the other hand, the second gas-liquid separator 56 supplies the heat medium from which the condensed water has been separated to the upstream heat transfer tube 33a.

The above-described first fluidizing gas supply line 55 has one end connected to the upstream heat transfer tube 33 a and the other end connected to the first chamber 18. For this reason, the 1st fluidization gas supply line 55 is supplying the heat medium which goes to the 2nd chamber chamber 19 from the upstream heat exchanger tube 33a as 1st fluidization gas. A first gas / liquid separator 57 is interposed in the first fluidizing gas supply line 55, and a heater 58 is interposed downstream of the first gas / liquid separator 57.

The first gas-liquid separator 57 separates condensed water (condensate) contained in the heat medium discharged from the upstream heat transfer tube 33a. The first gas-liquid separator 57 discharges the condensed water separated from the heat medium from a condensed water discharge line 60 provided with a pressure reducing valve 59. On the other hand, the first gas-liquid separator 57 supplies the heat medium from which the condensed water has been separated to the first chamber 18 via the first fluidized gas supply line 55.

The heater 58 is heating the 1st fluidization gas which passed the 1st gas-liquid separator 57, and the condensation isolate | separated from the 2nd gas-liquid separator 56 as a heat medium which heats the 1st fluidization gas. Water is used. Thereby, the heater 58 heats the first fluidizing gas by exchanging heat between the first fluidizing gas flowing in and the condensed water separated from the second gas-liquid separator 56. .

Thereby, the heat medium discharged from the upstream heat transfer pipe 33 a flows into the first gas-liquid separator 57 through the first fluidizing gas supply line 55. The heat medium flowing into the first gas-liquid separator 57 flows into the heater 58 as the first fluidized gas after the condensed water is separated. The first fluidizing gas that has flowed into the heater 58 is heated and then flows into the first chamber chamber 18. Therefore, the first fluidizing gas flowing into the first chamber 18 is compared with the second fluidizing gas by the amount of condensed water separated by the first gas-liquid separator 57 and the second gas-liquid separator 56. As a result, the vapor concentration is low.

Then, the flow of the exhaust gas in the fluidized bed drying apparatus 1 of Example 1 and the flow of the heat medium in the heat transfer tube 33 will be described. The first fluidized gas that has flowed into the first drying chamber 21 becomes exhaust gas together with the steam generated in the first drying chamber 21 and travels toward the gas outlet 13. The second fluidized gas that has flowed into the second drying chamber 22 becomes exhaust gas together with the vapor generated in the second drying chamber 22 and travels toward the gas discharge port 13.

The exhaust gas flowing in from the gas discharge port 13 passes through the first heat medium supply line 51 and passes through the dust collector 139 and the vapor compressor 135. Part of the exhaust gas that has passed through the steam compressor 135 becomes a heat medium, and flows into the downstream heat transfer pipe 33b through the first heat medium supply line 51. On the other hand, part of the exhaust gas that has passed through the vapor compressor 135 becomes the second fluidizing gas and flows into the second chamber 19 through the second fluidizing gas supply line 52. The second fluidizing gas that has flowed into the second chamber 19 is supplied to the second drying chamber 22 and is then discharged again from the gas outlet 13 as exhaust gas.

The heat medium that has flowed into the downstream heat transfer pipe 33 b is heat-exchanged with the brown coal in the second drying chamber 22, and then flows into the second gas-liquid separator 56. The heat medium flowing into the second gas-liquid separator 56 separates condensed water contained in the heat medium, and the separated condensed water flows into the heater 58 through the second heat medium supply line 61. Thus, the heat medium from which the condensed water has been separated flows into the upstream heat transfer tube 33a. The heat medium that has flowed into the upstream heat transfer pipe 33 a is heat-exchanged with the lignite in the first drying chamber 21, and then flows into the first fluidized gas supply line 55.

The heat medium flowing into the first fluidizing gas supply line 55 flows into the first gas-liquid separator 57. The heat medium flowing into the first gas-liquid separator 57 separates condensed water contained in the heat medium, and the condensed water separated is discharged through the condensed water discharge line 60, while the condensed water is The separated heat medium flows into the heater 58 as the first fluidizing gas. The heater 58 heats the first fluidized gas with the condensed water that has flowed through the second heat medium supply line 61. The heated first fluidizing gas flows into the first chamber chamber 18. The first fluidizing gas that has flowed into the first chamber 18 is supplied to the first drying chamber 21 and is then discharged again from the gas outlet 13 as exhaust gas.

As described above, according to the configuration of the first embodiment, the lignite in the first drying chamber 21 can be initially dried using the first fluidizing gas having a low vapor concentration, and in the second drying chamber 22. The lignite can be dried later using a second fluidizing gas with a high vapor concentration. Thereby, since the vapor | steam density | concentration of 1st fluidization gas is low, compared with 2nd fluidization gas, the efficiency of drying of lignite can be aimed at by making temperature of 1st fluidization gas low. Further, since the drying of the lignite can be promoted by the amount of the vapor concentration of the first fluidizing gas lower than that of the second fluidizing gas, the first fluidizing gas is compared with the second fluidizing gas. Even if the temperature of this is low, drying of lignite can be performed suitably.

Moreover, according to the structure of Example 1, since the exhaust gas discharged | emitted via the gas exhaust port 13 from the drying chamber 12 can be used as a heat medium of the heat exchanger tube 33, the latent heat of exhaust gas can be used effectively. The efficiency of drying lignite can be further improved.

Moreover, according to the structure of Example 1, since the heat medium discharged | emitted from the upstream heat exchanger tube 33a can be used as 1st fluidization gas, the part which can utilize a heat medium effectively, and efficiency of drying of lignite Can be further planned. Moreover, since the exhaust gas which flows through the 1st heat-medium supply line 51 can be used as 2nd fluidization gas, since the latent heat of exhaust gas can be used effectively, the efficiency improvement of lignite can be further achieved.

Moreover, according to the structure of Example 1, the 1st gas-liquid separator 57 isolate | separates the condensed water contained in the heat medium discharged | emitted from the upstream heat exchanger tube 33a, The heat medium from which the condensed water was isolate | separated The first fluidizing gas can be used. Thereby, since the 1st fluidization gas after condensed water separation becomes a thing with low vapor concentration, it can be conveniently used as the 1st fluidization gas.

Further, according to the configuration of the first embodiment, the first drying chamber 21 can be provided with the upstream heat transfer tube 33a, and the second drying chamber 22 can be provided with the downstream heat transfer tube 33b. For this reason, in the 1st drying chamber 21 into which the 1st fluidization gas flows in, after drying lignite with the 1st fluidization gas and the upstream heat exchanger tube 33a, the 2nd drying chamber 22 into which the 2nd fluidization gas flows in. The lignite can be dried by the second fluidizing gas and the downstream heat transfer tube 33b. Thereby, it can suppress that the lignite supplied from the lignite supply port 31 flows along a flow direction, and can be discharged | emitted from the lignite discharge port 41 in an undried state, and can dry lignite suitably. It becomes.

Moreover, according to the structure of Example 1, it can connect so that a heat medium may flow toward the upstream heat-transfer tube 33a from the downstream heat-transfer tube 33b. Therefore, the temperature of the downstream heat transfer pipe 33b provided in the second drying chamber 22 into which the second fluidizing gas flows is set to the temperature of the upstream heat transfer pipe provided in the first drying chamber 21 into which the first fluidizing gas flows. It can be made higher than the temperature of 33a. Thereby, lignite can be dried suitably, without condensing the vapor | steam contained in 1st fluidization gas and 2nd fluidization gas.

Moreover, according to the structure of Example 1, since the condensed water in the heat medium isolate | separated by the 2nd gas-liquid separator 56 can be used as a heat medium of the heater 58 which heats 1st fluidization gas. Further, the efficiency of drying lignite can be further increased by the amount that condensate water can be effectively used.

Further, according to the configuration of the first embodiment, the free board portion F can be divided by the upper partition plate 16 according to the first drying chamber 21 and the second drying chamber 22. For this reason, the condensation by the exhaust gas generated in the first drying chamber 21 and the exhaust gas generated in the second drying chamber 22 can be suppressed.

In the first embodiment, the upper partition plate 16 is provided in the free board portion F. However, the present invention is not limited to this configuration, and the upper partition plate 16 may be eliminated.

In addition, the lower partition plate 15 has its lower end connected to the gas dispersion plate 6, but this is not restrictive, and a gap may be provided between the lower partition plate 15 and the lower end. In this case, the gap may be used as a circulation port that connects the first drying chamber 21 and the second drying chamber 22, and the lignite may flow from the first drying chamber 21 to the second drying chamber 22 through the circulation port.

Moreover, although the lignite collected in the dust collector 139 is supplied to the dry coal bunker 132, the present invention is not limited to this configuration, and the lignite may be returned to the fluidized bed dryer 1.

Next, the fluidized bed drying apparatus 200 according to the second embodiment will be described with reference to FIG. FIG. 3 is a schematic configuration diagram schematically illustrating the fluidized bed drying apparatus according to the second embodiment. In the second embodiment, different parts will be described to avoid redundant description. In the fluidized bed drying apparatus 1 according to the first embodiment, the exhaust gas discharged from the gas discharge port 13 is compressed by the vapor compressor 135, but in the fluidized bed drying apparatus 200 according to the second embodiment, the gas discharged from the gas discharge port 13. A part of the discharged exhaust gas is compressed by the vapor compressor 135. Hereinafter, the fluidized bed drying apparatus 200 according to the second embodiment will be described.

In the fluidized bed drying apparatus 200 according to the second embodiment, the heat transfer tube 33 is provided inside the fluidized bed 3 of the upstream drying tube 33 a provided in the fluidized bed 3 of the first drying chamber 21 and the fluidized bed 3 of the second drying chamber 22. And a downstream heat transfer tube 33b.

The inflow side of the downstream heat transfer pipe 33 b is connected to the gas discharge port 13 via the first heat medium supply line 51, and the outflow side thereof is connected to the second gas-liquid separator 56. The first heat medium supply line 51 is provided with the dust collector 139, and the steam compressor 135 is provided downstream of the dust collector 139.

The second gas-liquid separator 56 separates condensed water (condensate) contained in the heat medium discharged from the downstream heat transfer tube 33b. The second gas-liquid separator 56 supplies the condensed water separated from the heat medium to the second heat medium supply line 61 in which the second flow rate adjustment valve 54 is interposed. The condensed water supplied to the second heat medium supply line 61 is supplied to the heater 58. On the other hand, the second gas-liquid separator 56 supplies the heat medium from which the condensed water has been separated to the first fluidizing gas merging line 208. The first fluidizing gas merging line 208 has one end connected to the second gas-liquid separator 56 and the other end connected to the first fluidizing gas supply line 55. For this reason, the 1st fluidization gas merge line 208 supplies the 1st fluidization gas supply line 55 with the heat medium after the condensed water separation discharged | emitted from the 2nd gas-liquid separator 56 as 1st fluidization gas. .

In addition, an extraction line 203 is connected to the first heat medium supply line 51 between the dust collector 139 and the steam compressor 135. One end of the extraction line 203 is connected to the first heat medium supply line 51, and the other end is connected to the inflow side of the upstream heat transfer tube 33a. A first blower 205 is interposed in the extraction line 203 and supplies the extracted exhaust gas toward the upstream heat transfer tube 33a. A second fluidizing gas supply line 52 is connected to the bleed line 203 on the downstream side of the first blower 205. The second fluidizing gas supply line 52 has one end connected to the extraction line 203 and the other end connected to the second chamber chamber 19. The second fluidizing gas supply line 52 supplies the exhaust gas supplied by the first blower 205 to the second chamber 19 as the second fluidizing gas.

The upstream heat transfer tube 33 a has an inflow side connected to the extraction line 203 and an outflow side connected to the first fluidizing gas supply line 55. A first gas-liquid separator 57 is interposed in the first fluidizing gas supply line 55, a heater 58 is interposed downstream of the first gas-liquid separator 57, and downstream of the heater 58. A second blower 206 is interposed.

Subsequently, the exhaust gas in the fluidized bed drying apparatus 200 of Example 2 and the flow of the heat medium in the heat transfer pipe 33 will be described. When the exhaust gas generated in the first drying chamber 21 and the second drying chamber 22 flows into the first heat medium supply line 51 through the gas discharge port 13, the exhaust gas passes through the first heat medium supply line 51, Passes through a dust collector 139. Part of the exhaust gas that has passed through the dust collector 139 flows into the extraction line 203, while the other part flows into the steam compressor 135.

The exhaust gas that has passed through the vapor compressor 135 becomes a heat medium and flows into the downstream heat transfer pipe 33b through the first heat medium supply line 51. The heat medium that has flowed into the downstream heat transfer pipe 33 b is heat-exchanged with the brown coal in the second drying chamber 22, and then flows into the second gas-liquid separator 56. The heat medium flowing into the second gas-liquid separator 56 separates condensed water contained in the heat medium, and the separated condensed water flows into the heater 58 through the second heat medium supply line 61. Thus, the heat medium from which the condensed water has been separated flows into the first fluidizing gas merging line 208.

On the other hand, the exhaust gas flowing into the extraction line 203 passes through the first blower 205. A part of the exhaust gas that has passed through the first blower 205 becomes the second fluidizing gas, and flows into the second chamber 19 through the second fluidizing gas supply line 52. The second fluidizing gas that has flowed into the second chamber 19 is supplied to the second drying chamber 22 and is then discharged again from the gas outlet 13 as exhaust gas. In addition, the exhaust gas that has passed through the first blower 205 flows into the upstream heat transfer tube 33a with the other part as a heat medium. The heat medium that has flowed into the upstream heat transfer pipe 33 a is heat-exchanged with the lignite in the first drying chamber 21, and then flows into the first fluidized gas supply line 55.

The heat medium flowing into the first fluidizing gas supply line 55 flows into the first gas-liquid separator 57. The heat medium flowing into the first gas-liquid separator 57 separates condensed water contained in the heat medium, and the condensed water separated is discharged through the condensed water discharge line 60, while the condensed water is The separated heat medium flows into the heater 58 as the first fluidizing gas. The heater 58 heats the first fluidized gas with the condensed water that has flowed through the second heat medium supply line 61. The heated first fluidizing gas passes through the second blower 206, merges with the first fluidizing gas flowing in from the first fluidizing gas merge line 208, and then flows into the first chamber 18. The first fluidizing gas that has flowed into the first chamber 18 is supplied to the first drying chamber 21 and is then discharged again from the gas outlet 13 as exhaust gas.

As described above, also in the configuration of the second embodiment, the lignite in the first drying chamber 21 can be initially dried using the first fluidized gas having a low vapor concentration, and the lignite in the second drying chamber 22 can be obtained. Can be dried later using a second fluidized gas having a high vapor concentration.

Further, according to the configuration of the second embodiment, the flow rate of the exhaust gas supplied to the steam compressor 135 is reduced by the amount of the exhaust gas flowing through the first heat medium supply line 51 being extracted through the extraction line 203. Therefore, the power of the steam compressor 135 can be reduced and the operation efficiency can be improved.

Next, with reference to FIG. 4 and FIG. 5, the fluidized bed drying apparatus 210 according to Example 3 will be described. FIG. 4 is a schematic configuration diagram schematically showing a fluidized bed drying apparatus according to Example 3, and FIG. 5 is an enthalpy temperature curve of a heat medium flowing through a heat transfer tube in the fluidized bed drying apparatus according to Example 3. And a graph showing an enthalpy temperature curve of lignite during drying. In the third embodiment, different parts will be described in order to avoid redundant description. In the fluidized bed drying apparatus 200 according to the third embodiment, by adjusting the flow rate of the fluidizing gas that flows into the chamber chamber 11, the fluidized bed drying device 200 is arranged on the downstream side in the flow direction as compared with the drying chamber located on the upstream side in the flow direction. The temperature of the drying chamber located is comprised so that it may become high. Hereinafter, the fluidized bed drying apparatus 210 according to the third embodiment will be described.

The fluidized bed drying apparatus 210 of Example 3 is configured by increasing the number of chamber chambers 11 and drying chambers 12 in the fluidized bed drying apparatus 1 of Example 1. In other words, the fluidized bed drying apparatus 210 has a plurality of chamber partition plates 14 and a plurality of lower partition plates 15. In Example 3, the upper partition plate 16 is omitted.

The plurality of chamber partition plates 14 divide the chamber chamber 11 into a first chamber chamber 18, a second chamber chamber 19, and a third chamber chamber 212 in order from the upstream side in the flow direction. At this time, the first fluidizing gas is supplied to the first chamber chamber 18 from the first fluidizing gas supply line 55, and the second fluidizing gas is supplied to the second chamber chamber 19 from the second fluidizing gas supply line 52. Gas is supplied. A third fluidizing gas supply line 215 is connected to the third chamber chamber 212, and one end of the third fluidizing gas supply line 215 is connected to the first heat medium supply line 51. The other end is connected to the third chamber 212. The third fluidizing gas supply line 215 is provided with a third flow rate adjusting valve 216 to adjust the flow rate of the third fluidizing gas flowing into the third chamber chamber 212.

Further, the plurality of lower partition plates 15 divide the drying chamber 12 into a first drying chamber 21, a second drying chamber 22, and a third drying chamber 213 in order from the upstream side in the flow direction. The first drying chamber 21 is provided with a first temperature sensor 221 inside the fluidized bed 3, the second drying chamber 22 is provided with a second temperature sensor 222 inside the fluidized bed 3, and the third drying chamber In 213, a third temperature sensor 223 is provided inside the fluidized bed 3. In the third embodiment, the temperature sensors 221, 222, and 223 are provided in the fluidized bed 3.

The heat transfer tube 33 includes a first heat transfer tube (upstream heat transfer tube) 33 a provided in the fluidized bed 3 of the first drying chamber 21 and a second heat exchanger 33 provided in the fluidized bed 3 of the second drying chamber 22. It has a heat transfer tube (downstream heat transfer tube) 33b and a third heat transfer tube 33c provided inside the fluidized bed 3 of the third drying chamber 213. And the 1st heat exchanger tube 33a, the 2nd heat exchanger tube 33b, and the 3rd heat exchanger tube 33c are connected so that the heat carrier which distribute | circulates the inside of the heat exchanger tube 33 may flow toward the upstream from the downstream of a flow direction. .

At this time, a second gas-liquid separator 56a is provided at a connection portion between the first heat transfer tube 33a and the second heat transfer tube 33b, and a connection portion between the second heat transfer tube 33b and the third heat transfer tube 33 is provided at the second portion. A gas-liquid separator 56b is provided. The condensed water separated by the second gas-liquid separators 56 a and 56 b is supplied to the second heat medium supply line 61.

Here, the first temperature sensor 221, the second temperature sensor 222, and the third temperature sensor 223 are connected to the control device 220 provided in the fluidized bed drying device 210, and the first flow rate adjusting valve 53 and the third temperature sensor 223 are connected. A flow rate adjustment valve 216 is connected. The control device 220 controls the first flow rate adjusting valve 53 and the third flow rate adjusting valve 216 based on the detected temperatures of the temperature sensors 221, 222, and 223, so that the first fluidizing gas and the second fluidizing gas are used. The flow rate of the third fluidizing gas is adjusted, and the temperatures of the drying chambers 22 and 213 located on the downstream side in the flow direction are higher than those of the drying chambers 21 and 22 located on the upstream side in the flow direction. So that it is controlled.

Specifically, when the temperature of the second drying chamber 22 becomes higher than the temperature of the first drying chamber 21, the control device 220 controls the first flow rate adjustment valve 53 to the valve closing side, thereby (2) The flow rate of the second fluidizing gas flowing into the drying chamber 22 is decreased. Similarly, when the temperature of the third drying chamber 213 becomes higher than the temperature of the second drying chamber 22, the third flow rate adjusting valve 216 is controlled to close to flow into the third drying chamber 213. The flow rate of the third fluidizing gas is decreased. The control device 220 is also connected to the second flow rate adjustment valve 54 and the pressure reducing valve 59 and is controlled as appropriate.

Next, the enthalpy temperature curve of the heat medium flowing through the heat transfer tube 33 and the enthalpy temperature curve of lignite during drying in the fluidized bed drying apparatus 210 according to Example 3 will be described with reference to FIG. In the graph shown in FIG. 5, L1 represents the enthalpy temperature curve of the heat medium flowing through the heat transfer tube 33, and L2 represents the enthalpy temperature curve of the lignite before drying. In FIG. 5, the left side in the figure is the upstream side in the flow direction, and the right side in the figure is the downstream side in the flow direction. For this reason, the range from the uppermost stream to the upstream step of the temperature curve L2 represents the range of the first drying chamber 21, and the range from the upstream step to the downstream step of the temperature curve L2 is the second drying chamber. 22 represents the range of the third drying chamber 213 from the step on the downstream side of the temperature curve L2 to the bent portion of the temperature curve L1. As shown in FIG. 5, since the temperature curve L1 can obtain a temperature difference with the temperature curve L2, it is confirmed that the lignite is suitably dried.

As described above, also in the configuration of Example 3, the lignite in the first drying chamber 21 can be initially dried using the first fluidized gas having a low vapor concentration, and the lignite in the second drying chamber 22 can be used. Can be dried later using a second fluidized gas having a high vapor concentration.

Further, according to the configuration of the third embodiment, the first flow rate adjusting valve 53 and the third flow rate adjusting valve 216 are controlled based on the detected temperatures of the temperature sensors 221, 222, and 223, so that the upstream side in the flow direction. As compared with the drying chambers 21 and 22 positioned at the same position, the temperature of the drying chambers 22 and 213 positioned on the downstream side in the flow direction can be increased. Thereby, since the latent heat of exhaust gas can be appropriately distributed as each fluidization gas, the latent heat of exhaust gas can be used efficiently.

Next, a fluidized bed drying apparatus 230 according to Example 4 will be described with reference to FIGS. 6 is a schematic configuration diagram schematically illustrating a fluidized bed drying apparatus according to Example 4, and FIG. 7 is an enthalpy temperature curve of a heat medium flowing through a heat transfer tube in the fluidized bed drying apparatus according to Example 4. And a graph showing an enthalpy temperature curve of lignite during drying. In the fourth embodiment, different parts will be described in order to avoid redundant description. In the fluidized bed drying apparatus 230 according to the fourth embodiment, the drying chamber 12 is not divided into a plurality of drying chambers. With this configuration, the drying chamber 12 is provided with a single heat transfer tube 33. Yes.

That is, the fluidized bed drying apparatus 230 of Example 4 has a configuration in which the lower partition plate 15 and the upper partition plate 16 are eliminated. Note that the heat transfer tube 33 provided in the drying chamber 12 is configured such that the heat medium flowing inside flows from the downstream side to the upstream side in the flow direction. The shape of the heat transfer tube 33 may be linear or bellows and is not particularly limited.

Next, the enthalpy temperature curve of the heat medium flowing through the heat transfer tube 33 and the enthalpy temperature curve of lignite during drying in the fluidized bed drying apparatus 230 according to Example 4 will be described with reference to FIG. In the graph shown in FIG. 7, L1 represents the enthalpy temperature curve of the heat medium flowing through the heat transfer tube 33, and L2 represents the enthalpy temperature curve of the brown coal before drying. In FIG. 7, the left side in the figure is the upstream side in the flow direction, and the right side in the figure is the downstream side in the flow direction. As shown in FIG. 7, since the temperature curve L1 can stably obtain a certain temperature difference from the temperature curve L2 from the upstream side to the downstream side in the flow direction, the lignite is suitably dried. To be confirmed.

As described above, also in the configuration of Example 4, the lignite on the upstream side in the flow direction of the drying chamber 12 can be initially dried using the first fluidized gas having a low vapor concentration. The lignite at the downstream side in the flow direction can be dried later using a second fluidized gas having a high vapor concentration. At this time, since the structure of the fluidized bed drying apparatus 230 can be simplified, the apparatus cost can be reduced.

DESCRIPTION OF SYMBOLS 1 Fluidized bed drying apparatus 3 Fluidized bed 5 Drying furnace 6 Gas dispersion | distribution plate 11 Chamber chamber 12 Drying chamber 13 Gas exhaust port 14 Chamber partition plate 15 Lower partition plate 16 Upper partition plate 18 1st chamber chamber 19 2nd chamber chamber 21 1st Drying chamber 22 Second drying chamber 31 Supply port 33 Heat transfer tube 41 Discharge port 51 First heat medium supply line 52 Second fluidization gas supply line 53 First flow rate adjustment valve 54 Second flow rate adjustment valve 55 First fluidization gas supply Line 56 Second gas-liquid separator 57 First gas-liquid separator 58 Heater 59 Pressure reducing valve 60 Condensate discharge line 61 Second heat medium supply line 200 Fluidized bed drying apparatus (Example 2)
203 Extraction line 205 1st blower 206 2nd blower 208 1st fluidization gas confluence line 210 Fluidized bed drying apparatus (Example 3)
212 Third chamber chamber 213 Third drying chamber 215 Third fluidizing gas supply line 216 Third flow regulating valve 220 Controller 221 First temperature sensor 222 Second temperature sensor 223 Third temperature sensor 230 Fluidized bed drying apparatus (Example) 4)
F Free board club

Claims (10)

In the fluidized bed drying apparatus capable of drying the wet fuel while forming the fluidized bed by flowing the wet fuel with the fluidized gas.
A drying furnace;
A gas jetting unit that divides the inside of the drying furnace into a chamber chamber into which the fluidized gas flows and a drying chamber to which the wet fuel is supplied, and allows the fluidized gas to flow into the drying chamber from the chamber chamber And comprising
A plurality of the chamber chambers are provided along the flow direction of the wet fuel,
The first fluidized gas having a low vapor concentration flows into the chamber chamber located on the upstream side in the flow direction,
The fluidized bed drying apparatus, wherein a second fluidized gas having a higher vapor concentration flows into the chamber chamber located downstream in the flow direction than the first fluidized gas. A heat transfer pipe that is provided in the drying chamber and flows in the flow direction from the downstream side to the upstream side in the flow direction; and
A gas discharge port for discharging exhaust gas generated in the drying chamber;
A first heat medium supply line connecting the gas discharge port and the inflow side of the heat transfer tube;
2. The compressor according to claim 1, further comprising a compressor interposed in the first heat medium supply line and capable of compressing the exhaust gas and supplying the compressed heat gas as the heat medium of the heat transfer tube. Fluidized bed dryer. A first fluidizing gas supply line connecting the outflow side of the heat transfer tube and the chamber chamber located upstream in the flow direction;
The flow according to claim 2, further comprising a second fluidizing gas supply line that connects the first heat medium supply line and the chamber chamber located downstream in the flow direction. Layer dryer. The apparatus further comprises a first gas-liquid separator interposed in the first fluidizing gas supply line and capable of separating condensate contained in the heat medium discharged from the heat transfer tube. 4. The fluidized bed drying apparatus according to 3. A first partition member for dividing the drying chamber into a plurality of chambers according to the plurality of chamber chambers;
The fluidized bed drying apparatus according to any one of claims 2 to 4, wherein the heat transfer tubes are respectively provided according to the plurality of drying chambers. Temperature detection sensors provided in the plurality of drying chambers;
A flow rate adjustment valve capable of adjusting a flow rate of the second fluidizing gas;
A control device that controls the flow rate adjustment valve based on the temperature detected by the temperature detection sensor; and
The control device controls the flow rate adjustment valve so that the temperature of the drying chamber located downstream in the flow direction is higher than that of the drying chamber located upstream in the flow direction. The fluidized bed drying apparatus according to claim 5. In the plurality of heat transfer tubes provided in the plurality of chamber chambers, the heat medium flows from the heat transfer tube located on the downstream side in the flow direction toward the heat transfer tube located on the upstream side in the flow direction. The fluidized bed drying apparatus according to claim 5 or 6, wherein the fluidized bed drying apparatus is connected to the fluidized bed. A second air that is provided at a connection portion between the heat transfer tube located on the downstream side in the flow direction and the heat transfer tube located on the upstream side in the flow direction and capable of separating the condensate contained in the heat medium. A liquid separator;
A heater capable of heating the first fluidizing gas;
8. A second heat medium supply line for feeding the condensate separated by the second gas-liquid separator into the heater as a heat medium for the heater, further comprising: The fluidized bed drying apparatus described in 1. Further comprising an extraction line for extracting the exhaust gas from the first heat medium supply line,
The first heat medium supply line connects the gas discharge port and the inflow side of the heat transfer tube located on the downstream side,
The extraction line connects the first heat medium supply line and the inflow side of the heat transfer pipe located on the upstream side,
The compressor is provided in the first heat medium supply line located downstream of a connection portion where the first heat medium supply line and the extraction line are connected. The fluidized bed drying apparatus according to 5 or 6. A second partition member that is provided in the drying furnace and that divides a free board portion positioned above the fluidized bed formed in the plurality of drying chambers into a plurality of according to the plurality of drying chambers is further provided. The fluidized bed drying apparatus according to any one of claims 5 to 9, wherein

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