JP2017166740A - Drying system and activation method of drying system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress deterioration of dust removal efficiency of a bag filer.SOLUTION: A drying system 100 configured to form a fluid bed of a hydrous solid and dry the hydrous solid, includes: a fluid bed furnace (first storage part 212) capable of forming the fluid bed of the hydrous solid; a raw material input part 110 configured to input the hydrous solid to the fluid bed furnace; a gas supply unit (first gas supply unit 220) configured to supply gas from a bottom surface of the fluid bed furnace; a bag filter 260 configured to filter gas discharged from the fluid bed furnace; a connecting pipe 250 connecting the fluid bed furnace and the bag filter 260; and a superheated steam supply unit 280 configured to supply superheated steam to the connection pipe 250.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a drying system that forms a fluidized bed of hydrated solids and dries the hydrated solids, and a startup method of the drying system.

  Coal is a natural resource that can be stably supplied over a long period because it has a recoverable life of about 150 years, which is more than three times that of oil, and because the reserves are not unevenly distributed compared to oil. As expected. Coal is classified into peat, lignite, lignite, sub-bituminous coal, bituminous coal, semi-anthracite, anthracite, in order of increasing carbon content. The water content (water content) is higher than semi-anthracite and anthracite (hereinafter referred to as anthracite).

  Among hydrous solid fuels, lignite is said to occupy half of the world's coal reserves, so effective utilization of lignite is being studied. However, as described above, a hydrated solid fuel such as lignite has a higher moisture content than anthracite and the like, and therefore has a low calorific value per unit weight and a low energy efficiency as a fuel for transportation costs.

  Therefore, a technique has been developed in which a hydrous solid fuel is crushed and charged into a fluidized bed furnace, and a fluidized bed of hydrous solid fuel particles is formed in the fluidized bed furnace and dried (for example, Patent Document 1).

JP 2011-214812 A

However, since the hydrated solid fuel contains a large amount of volatile organic substances, when a gas (for example, air) containing oxygen (O ₂ ) is used as the fluidizing gas when the hydrated solid fuel is dried, the hydrated solid fuel contains water. Solid fuel may burn.

  Therefore, it is conceivable to use water vapor as the fluidizing gas instead of the gas containing oxygen. However, when water vapor is used, it is cooled in the fluidized bed furnace or cooled in the bag filter that filters and removes the gas discharged from the fluidized bed furnace, so that the water vapor is condensed and water ( Liquid) may adhere, and the dust removal efficiency of the bag filter may decrease.

  In view of such a problem, an object of the present invention is to provide a drying system capable of suppressing a decrease in dust removal efficiency of a bag filter and a starting method of the drying system.

  In order to solve the above problems, a drying system according to the present invention is a drying system that forms a fluidized bed of hydrous solids and dries the hydrous solids, and is capable of forming a fluidized bed of the hydrous solids. A bed furnace, a raw material charging section for charging the hydrated solid material into the fluidized bed furnace, a gas supply section for supplying gas from the bottom surface of the fluidized bed furnace, and a bug for filtering the gas discharged from the fluidized bed furnace A connecting pipe connecting the filter, the fluidized bed furnace, and the bag filter, and a superheated steam supply unit that supplies superheated steam to the bag filter through the connecting pipe.

  Further, the connection pipe is provided with a heat exchanger for heating the gas passing through the connection pipe, and the superheated steam supply unit is located downstream from the heating place by the heat exchanger in the connection pipe, and The superheated steam may be supplied to the bag filter through an inlet formed at a position upstream from the connection point with the bag filter.

  The superheated steam supply unit may stop the supply of the superheated steam when a predetermined stop condition is satisfied.

  In addition, a temperature measurement unit that measures the temperature of the gas discharged from the bag filter may be provided, and the stop condition may be that the temperature measured by the temperature measurement unit reaches a predetermined temperature threshold value. Good.

  When the superheated steam supply unit stops the supply of the superheated steam, the gas supply unit may increase the supply amount of the gas by the supply amount of the superheated steam.

  The raw material charging unit may start charging the hydrated solid material into the fluidized bed furnace when the supply of the superheated steam is stopped by the superheated steam supply unit.

  In order to solve the above-mentioned problems, a method for starting a drying system according to the present invention is a method for starting a drying system in which a fluidized bed of water-containing solids is formed in a fluidized bed furnace to dry the water-containing solids. A gas is supplied from the bottom of the bed furnace, superheated steam is added to the gas discharged from the fluidized bed furnace, and at least the gas is supplied to a bag filter that filters the gas.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to suppress the fall of the dust removal efficiency of a bag filter.

It is a figure which shows the schematic of a drying system. It is a flowchart which shows the flow of a process of the starting method of a drying system.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The dimensions, materials, and other specific numerical values shown in the embodiments are merely examples for facilitating the understanding of the invention, and do not limit the present invention unless otherwise specified. In the present specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals, and redundant description is omitted, and elements not directly related to the present invention are not illustrated. To do.

  In the present embodiment, a drying system 100 that dries lignite (hydrated solid fuel) as a hydrated solid and a starting method of the drying system 100 will be described.

(Drying system 100)
FIG. 1 is a schematic diagram of a drying system 100. In FIG. 1, the flow of lignite is indicated by an alternate long and short dash line, the flow of gas such as water vapor and exhaust gas is indicated by a solid line arrow, and the signal flow is indicated by a broken line arrow.

  As shown in FIG. 1, the drying system 100 includes a raw material charging unit 110, a first drying furnace 210, a second drying furnace 310, a cooling unit 410, and a control unit 510.

  In the drying system 100 of this embodiment, undried lignite is introduced into the first drying furnace 210 by the raw material charging unit 110, and free water (water that is relatively easily evaporated) contained in the lignite in the first drying furnace 210. In the second drying furnace 310, the combined water contained in the lignite from which free water has been removed (water that is relatively difficult to evaporate) is vaporized and removed. In the cooling unit 410, the second drying is performed. The lignite dried in the furnace 310 is cooled.

  Hereinafter, specific configurations of the raw material charging unit 110, the first drying furnace 210, the second drying furnace 310, the cooling unit 410, and the control unit 510 will be described.

(Raw material input part 110)
The raw material charging unit 110 includes a hopper 112 and a communication pipe 114. The hopper 112 temporarily stores lignite. The communication pipe 114 is a pipe that connects the hopper 112 and a first storage part 212 of the first drying furnace 210 described later, and the communication pipe 114 is provided with a rotary valve 116. In this embodiment, since the hopper 112 is provided above the 1st accommodating part 212, the brown coal stored in the hopper 112 is carried into the 1st accommodating part 212 with dead weight by controlling opening of the rotary valve 116. Will be thrown in.

(First drying furnace 210)
The first drying furnace 210 includes a first storage part 212 (fluidized bed furnace), a first gas supply part 220 (gas supply part), a first heat transfer part 230, a gas-liquid separation part 240, and a connecting pipe 250. And a bag filter 260, a heat exchanger 270, a superheated steam supply unit 280, and a temperature measuring unit 290. The first storage unit 212 stores the lignite introduced by the raw material input unit 110.

  The first gas supply unit 220 includes a wind box 222 and a blower 224 that feeds a first fluidizing gas (for example, water vapor) into the wind box 222, and the first fluidization is performed from the bottom surface of the first storage unit 212. Supply gas.

  The wind box 222 is provided below the first storage unit 212. When the drying system 100 is operated, the first fluidization is performed from the bottom surface of the first storage unit 212 through the wind box 222 into the first storage unit 212. Gas will be supplied. More specifically, the upper portion of the wind box 222 functions as a bottom surface of the first housing portion 212 and is formed of a dispersion plate 222a that can be ventilated. The dispersion plate 222a is, for example, a plate provided with a plurality of apertures having a diameter smaller than the particle size of lignite (particles having the smallest particle size among lignite particles), or an aperture having a diameter smaller than the particle size of lignite. It is comprised with the board which installed the nozzle provided.

  The blower 224 feeds the first fluidized gas into the wind box 222 at a flow rate determined by the control unit 510 described later, for example, at a flow rate that can stably form a fluidized bed of lignite in the first storage unit 212.

  In the present embodiment, the blower 224, together with a blower 252 to be described later, is water vapor (for example, 103 ° C. water vapor, hereinafter referred to as “free water” generated by heating the lignite in the first housing part 212 and evaporating free water. (Referred to as “water vapor derived from”), and dust removed by a bag filter 260 described later is pressurized (compressed) and sent to the wind box 222 as a first fluidized gas.

  Thus, the first fluidized gas supplied to the first storage unit 212 by the first gas supply unit 220 causes the lignite to flow in the first storage unit 212 to form a fluidized bed, and the first fluidized gas. A part of the free water contained in the lignite is vaporized by bringing the lignite into contact with the lignite. In addition, the 1st fluidization gas supplied to the 1st accommodating part 212 is adjusted to the temperature (for example, 120 degreeC) which evaporates free water efficiently.

  The first heat transfer unit 230 is constituted by, for example, a pipe through which a heat medium flows, and is arranged inside the first storage unit 212. The 1st heat-transfer part 230 heats lignite with the heat | fever which a heat medium has in the distribution | circulation process of a heat medium. In the present embodiment, the steam that is supplied to the heat exchanger 270 by the superheated steam supply unit 280 to be described later and removed by the heat exchanger 270 is supplied to the first heat transfer unit 230. In addition, the water vapor | steam (heat medium) supplied to the 1st heat-transfer part 230 is adjusted to the temperature (for example, 120 degreeC) and flow volume which evaporate the free water of lignite efficiently.

  With the configuration including the first heat transfer unit 230, heat exchange is performed between the heat medium and the first fluidizing gas in the first housing unit 212, and the first fluidizing gas moving upward is further heated. can do. Therefore, drying of lignite (vaporization of free water) with the first fluidizing gas is further promoted.

  In addition, when heat exchange is performed between the heat medium and the first fluidizing gas in the first heat transfer section 230 (the outer surface of the pipe constituting the first heat transfer section 230), a part of the heat medium is transferred to the first heat transfer section 230. It will condense in the heat section 230. Therefore, a gas-liquid separation unit 240 is provided, and the heat medium sent from the first heat transfer unit 230 is gas-liquid separated by the gas-liquid separation unit 240. In this way, the separated condensed heat medium (liquid water) is sent to the outside (for example, a condenser condenser for improving the efficiency of the superheated steam supply unit 280).

  In this way, in the first drying furnace 210, undried lignite is introduced into the first storage unit 212, the lignite is heated by the first gas supply unit 220 and the first heat transfer unit 230, and free water is vaporized from the lignite. To be removed. On the other hand, when the flow of lignite is described, when undried lignite is introduced into the first storage unit 212 by the raw material charging unit 110, the volume of the introduced lignite and the volume of the fluidized bed increase. Then, the lignite from which the free water has been removed overflows (is discharged) from the outlet of the first storage unit 212, and passes through the piping that connects the first storage unit 212 and the second storage unit 312 of the second drying furnace 310. It will be introduced into the second housing part 312.

  In addition, free water (water vapor of about 103 ° C.) vaporized in the first drying furnace 210 is introduced into the bag filter 260 through the connection pipe 250. The bag filter 260 filters (dedusts) the gas (water vapor) discharged from the first drying furnace 210.

  Further, the connection pipe 250 is provided with a heat exchanger 270 that heats the gas passing through the connection pipe 250, and the superheated steam is supplied to the heat exchanger 270 by the superheated steam supply unit 280 configured by a steam turbine. Supplied. With the configuration including the heat exchanger 270, condensation of water vapor discharged from the first drying furnace 210 can be suppressed. Therefore, adhesion of water (liquid) to the bag filter 260 can be suppressed, and the dust removal efficiency of the bag filter 260 can be maintained.

  Thus, the superheated steam supplied to the heat exchanger 270 by the superheated steam supply unit 280 is removed by heating the gas passing through the connection pipe 250 by the heat exchanger 270, and then the first heat transfer unit 230. Will be introduced.

  In addition, the superheated steam supply unit 280 passes through the inlet formed in the connection pipe 250 at a position downstream of the heating position by the heat exchanger 270 and upstream of the connection position with the bag filter 260. Supply superheated steam. A temperature measuring unit 290 that measures the temperature of the gas exhausted from the bag filter 260 is provided on the downstream side of the bag filter 260. The superheated steam supply process by the superheated steam supply unit 280 and the temperature measurement unit 290 will be described in detail later.

  Thus, the gas (water vapor) filtered by the bag filter 260 is sent again to the wind box 222 by the blowers 252 and 224, or is sent to the second heat transfer section 330 of the second drying furnace 310 described later by the blowers 252 and 332. It is supplied or discharged to the outside by the blower 252. The pipes connecting the blower 252 and the blower 332 and the pipe connecting the blower 252 and the atmosphere open end are provided with dampers 254a and 254b, and by adjusting the opening degree of the dampers 254a and 254b. The flow rate of the gas supplied to the wind box 222 and the second heat transfer unit 330 is adjusted.

(Second drying furnace 310)
The second drying furnace 310 includes a second storage unit 312, a second gas supply unit 320, a second heat transfer unit 330, a gas-liquid separation unit 340, and a bag filter 360. The second storage unit 312 stores lignite from which free water has been removed by the first drying furnace 210.

  Similar to the first gas supply unit 220 constituting the first drying furnace 210, the second gas supply unit 320 includes an air box 322 and a blower 324 that feeds the second fluidizing gas into the air box 322. The second fluidizing gas is supplied from the bottom surface of the second housing portion 312.

  The wind box 322 is provided below the second storage unit 312, and when the drying system 100 is operated, the second fluidization is performed from the bottom surface of the second storage unit 312 through the wind box 322 into the second storage unit 312. Gas will be supplied. More specifically, the upper portion of the wind box 322 functions as a bottom surface of the second housing portion 312 and is formed of a dispersion plate 322a that can be ventilated. The dispersion plate 322a is, for example, a plate provided with a plurality of apertures having a diameter smaller than the particle size of lignite (particles having the smallest particle size among lignite particles) or an aperture having a diameter smaller than the particle size of lignite. It is comprised with the board which installed the nozzle provided.

  The blower 324 generates the second fluidized gas (for example, water vapor or air) at the flow rate determined by the control unit 510, for example, the flow rate at which the fluidized bed of lignite can be stably formed in the second storage unit 312. To send.

  Thus, the second fluidized gas supplied to the second storage unit 312 by the second gas supply unit 320 causes the lignite to flow in the second storage unit 312 to form a fluidized bed, and the second fluidized gas. A part of the combined water contained in the lignite is vaporized by bringing the lignite into contact with the lignite. In addition, the 2nd fluidization gas supplied to the 2nd accommodating part 312 is adjusted to the temperature (for example, 115 degreeC) which evaporates combined water efficiently.

  Similarly to the first heat transfer unit 230 that configures the first drying furnace 210, the second heat transfer unit 330 includes, for example, a pipe through which a heat medium flows and is disposed in the second storage unit 312. The second heat transfer unit 330 heats the lignite with the heat of the heat medium in the circulation process of the heat medium. In the present embodiment, the steam derived from free water, which has been dust-removed by the bag filter 260 by the blowers 252 and 332, is pressurized (compressed) (for example, becomes steam at about 200 ° C.), and the second heat transfer as a heat medium. Supplied to the unit 330.

  With the configuration including the second heat transfer unit 330, heat exchange is performed between the heat medium and the second fluidizing gas in the second housing unit 312 to further heat the second fluidizing gas moving upward. can do. Therefore, drying of lignite (vaporization of bound water) with the second fluidizing gas is further promoted.

  In addition, when heat exchange is performed between the heat medium and the second fluidizing gas in the second heat transfer section 330 (the outer surface of the pipe constituting the second heat transfer section 330), a part of the heat medium is transferred to the second heat transfer section 330. It will condense in the heat part 330. Therefore, a gas-liquid separation unit 340 is provided, and the gas-liquid separation unit 340 gas-liquid separates the heat medium sent from the second heat transfer unit 330. In this way, the separated condensed heat medium (liquid water) is sent to the outside.

  As described above, in the second drying furnace 310, the lignite from which free water has been removed in the first drying furnace 210 is introduced into the second storage unit 312, and the lignite is generated by the second gas supply unit 320 and the second heat transfer unit 330. When heated, the bound water is vaporized and removed from the lignite. On the other hand, when the flow of lignite is described, when lignite from which free water has been removed is introduced from the first drying furnace 210 into the second storage unit 312, the volume of the introduced lignite and the volume of the fluidized bed increase. Then, the lignite (fluidized bed) from which the bound water has been removed overflows from the outlet of the second storage unit 312 and is stored in the third storage through a pipe that connects the second storage unit 312 and the third storage unit 412 of the cooling unit 410. The part 412 is introduced.

  Further, the combined water (water vapor of about 115 ° C.) vaporized in the second drying furnace 310 is removed by the bag filter 360 and then exhausted to the outside by the blower 362.

(Cooling unit 410)
The cooling unit 410 includes a third storage unit 412 and a cooling gas supply unit 420. The 3rd accommodating part 412 accommodates the lignite from which combined water was removed by the 2nd drying furnace 310. FIG. Like the first gas supply unit 220 and the second gas supply unit 320, the cooling gas supply unit 420 includes an air box 422 and a blower 424 that feeds cooling gas (for example, air) into the air box 422. The The air box 422 is provided below the third housing part 412, and when operating the drying system 100, cooling gas is supplied into the third housing part 412 from the bottom surface of the third housing part 412 through the air box 422. Will be.

  More specifically, the upper portion of the wind box 422 is formed of a dispersion plate 422a that also functions as a bottom surface of the third housing portion 412 and is air permeable. The dispersion plate 422a is configured by, for example, a plate provided with a plurality of openings having a diameter smaller than the particle size of lignite, or a plate provided with a nozzle provided with an opening having a diameter smaller than the particle size of lignite. .

  By the structure provided with the cooling unit 410, the lignite from which free water and combined water have been removed can be cooled (for example, up to about 50 ° C). The lignite that has been cooled in this way is sent to the lignite utilization facility at the subsequent stage.

  The gas exhausted from the cooling unit 410 is exhausted to the outside after being removed by the bag filter 360.

  As described above, in the drying system 100 according to the present embodiment, the lignite is dried with water vapor in the first drying furnace 210. Here, after the normal operation (rated operation) is reached, since the functional units constituting the first drying furnace 210 including the first storage unit 212 are maintained at an appropriate temperature, water vapor derived from free water condenses. There is nothing. However, the normal operation has not been reached, that is, when the drying system 100 is started, the first gas storage unit 212, the connecting pipe 250, the bag filter 260, and the like are at normal temperature (for example, 25 ° C.), so the first gas The water vapor supplied by the supply unit 220 is cooled by the first storage unit 212, the connection pipe 250, and the bag filter 260, condensed, and mixed into the bag filter 260.

  Therefore, when starting the drying system 100, it is conceivable to supply nitrogen as the first fluidizing gas and switch the first fluidizing gas to water vapor when the first drying furnace 210 reaches an appropriate temperature. However, this configuration has a problem that the cost becomes enormous.

  Therefore, the superheated steam supply unit 280 supplies superheated steam having a large heat capacity to the bag filter 260 through the connection pipe 250 when the drying system 100 is activated. Thereby, the temperature of the connection pipe 250 and the bag filter 260 can be made higher than the condensation temperature of water, and the situation where water vapor is condensed in the connection pipe 250 and the bag filter 260 can be avoided. Accordingly, it is possible to prevent water (liquid) from adhering to the bag filter 260, and it is possible to suppress a decrease in dust removal efficiency of the bag filter 260.

  Hereinafter, the superheated steam supply process to the bag filter 260 through the connection pipe 250 by the superheated steam supply unit 280 at the time of startup will be described in detail.

  The control unit 510 is composed of a semiconductor integrated circuit including a CPU (Central Processing Unit), reads out programs and parameters for operating the CPU itself from the ROM, and cooperates with the RAM as a work area and other electronic circuits. Thus, the amount of superheated steam supplied to the connecting pipe 250 by the superheated steam supply unit 280 is controlled.

  FIG. 2 is a flowchart showing a processing flow of the activation method of the drying system 100. In the initial state, the raw material charging unit 110 has stopped charging the lignite, and no lignite is stored in the first storage unit 212, the second storage unit 312, and the third storage unit 412 (empty). Is).

(Step S110: Gas supply process)
The control unit 510 controls the first gas supply unit 220 (blower 224) to supply water vapor (first fluidization gas) to the wind box 222 from a first fluidization gas supply source (not shown).

(Step S120: Superheated steam supply process)
Control unit 510 adjusts the opening degree of valve 282 provided in a pipe connecting superheated steam supply unit 280 and connecting pipe 250 to supply superheated steam to connecting pipe 250. Then, superheated steam is added to the first fluidizing gas and supplied to the bag filter 260. As a result, the first fluidized gas and superheated steam are filtered by the bag filter 260, and the bag filter 260 is warmed up. Therefore, adhesion of water (liquid) to the bag filter 260 can be suppressed. Control unit 510 also starts supplying superheated steam from superheated steam supply unit 280 to heat exchanger 270.

(Step S130: Stop condition determination step)
Control unit 510 determines whether a predetermined stop condition is satisfied. Specifically, the control unit 510 determines whether the temperature of the gas measured by the temperature measurement unit 290 (the temperature of the gas discharged from the bag filter 260) has reached a predetermined temperature threshold (is equal to or higher than the temperature threshold). )). As a result, when it is determined that the temperature threshold has been reached, the process proceeds to step S140, and when it is determined that the temperature threshold has not been reached, the stop condition determination step is repeated. Here, the temperature threshold is a temperature at which water (liquid) does not adhere to the bag filter 260 even when the supply of superheated steam is stopped (for example, 105 ° C.).

(Step S140: Superheated steam supply stop process)
The control unit 510 closes the valve 282 and stops the supply of superheated steam from the superheated steam supply unit 280 to the connection pipe 250 (bag filter 260). Thereby, unnecessary consumption of superheated steam can be reduced.

(Step S150: Gas supply amount increasing step)
The control unit 510 controls the first gas supply unit 220 (blower 224) to increase the supply amount of the first fluidized gas by the supply amount of the superheated steam supplied in the superheated steam supply process of step S120. Let

  In this way, the start-up process of the drying system 100 is completed, and the raw material charging unit 110 starts to input lignite and starts normal operation (drying of lignite).

  As described above, in the drying system 100 and the activation method of the drying system 100 according to the present embodiment, the superheated steam supply unit 280 supplies superheated steam to the bag filter 260 through the connection pipe 250, so that the connection pipe 250, The situation in which water vapor is condensed in the bag filter 260 can be avoided, and the adhesion of water (liquid) to the bag filter 260 can be prevented. Thereby, the fall of the dust removal efficiency of the bag filter 260 can be suppressed.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to this embodiment. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Is done.

  For example, in the said embodiment, lignite was mentioned as an example and demonstrated as a water-containing solid substance. However, if the drying system 100 is configured to contain water, it can dry hydrous solid fuels such as peat, lignite and subbituminous coal, and other hydrous solids.

  Moreover, in the said embodiment, the superheated steam supply part 280 demonstrated and demonstrated as an example the structure which supplies superheated steam to the bag filter 260 (connection pipe 250) only at the time of starting of the drying system 100. However, the superheated steam supply unit 280 may supply superheated steam to the bag filter 260 (connection pipe 250) even during normal operation. In this case, the heat exchanger 270 may not be provided.

  Moreover, in the said embodiment, the temperature which the temperature measurement part 290 measured as a stop condition at the time of stopping supply of the superheated steam to the bag filter 260 (connection pipe 250) by the superheated steam supply part 280 was defined beforehand. The description has been given by taking the example of reaching the temperature threshold. However, the stop condition may be that a predetermined time elapses. Here, the predetermined time is a time for the bag filter 260 to reach a temperature at which water (liquid) does not adhere to the bag filter 260 even if the supply of superheated steam is stopped. In this case, the temperature measurement unit 290 may not be provided.

  Moreover, in the said embodiment, the structure which performs a starting process in the state in which the brown coal is not accommodated in the 1st accommodating part 212 was mentioned as an example, and was demonstrated. However, the startup process may be performed in a state where lignite is stored in the first storage unit 212 or when the lignite is input by the raw material input unit 110.

  In the above embodiment, when the superheated steam supply unit 280 stops supplying superheated steam, the first gas supply unit 220 increases the supply amount of the first fluidized gas by the amount of superheated steam supplied. Was described as an example. However, the first gas supply unit 220 may not increase the supply amount of the first fluidizing gas even if the supply of superheated steam by the superheated steam supply unit 280 is stopped. In any case, the first fluidizing gas may be supplied in such a supply amount that the lignite fluidized bed is stably formed in the first accommodating portion 212.

  Moreover, in the said embodiment, the superheated steam supply part 280 demonstrated and demonstrated the structure which supplies superheated steam to the connection pipe 250 and the heat exchanger 270 as an example. However, the superheated steam supply unit 280 may supply superheated steam only to the connection pipe 250 (bug filter 260), or may be provided at other locations, for example, the first storage unit 212, the second storage unit 312 and the bag filter 360. The superheated steam may be supplied to the bag filter 360 through a pipe connecting the two. Accordingly, it is possible to prevent water (liquid) from adhering not only to the bag filter 260 but also to the bag filter 360, and it is possible to suppress a decrease in dust removal efficiency of the bag filter 360.

  Moreover, in the said embodiment, the case where the drying system 100 was provided with two drying furnaces (1st drying furnace 210, 2nd drying furnace 310) was mentioned as an example, and was demonstrated. However, the drying system may include only one drying furnace.

  Moreover, the 1st drying furnace 210, the 2nd drying furnace 310, and the cooling part 410 may each be comprised by one accommodating part, and may be comprised including the some accommodating part.

  INDUSTRIAL APPLICATION This invention can be utilized for the starting method of the drying system which forms the fluidized bed of a hydrous solid substance, and dries a hydrous solid substance, and a drying system.

100 Drying System 110 Raw Material Input Unit 212 First Storage Unit (Fluidized Bed Furnace)
220 1st gas supply part (gas supply part)
250 Connection Pipe 260 Bag Filter 270 Heat Exchanger 280 Superheated Steam Supply Unit 290 Temperature Measurement Unit

Claims (7)

A drying system for forming a fluidized bed of hydrous solids to dry the hydrous solids,
A fluidized bed furnace capable of forming a fluidized bed of the hydrous solids;
A raw material charging unit for charging the hydrous solids into the fluidized bed furnace;
A gas supply unit for supplying gas from the bottom of the fluidized bed furnace;
A bag filter for filtering the gas discharged from the fluidized bed furnace;
A connecting pipe connecting the fluidized bed furnace and the bag filter;
A superheated steam supply section for supplying superheated steam to the bag filter through the connection pipe;
A drying system comprising: The connection pipe is provided with a heat exchanger for heating the gas passing through the connection pipe,
The superheated steam supply unit is connected to the bag filter through an inlet formed at a position downstream from a heating location by the heat exchanger and upstream from a connection location with the bag filter in the connection pipe. The drying system according to claim 1, wherein superheated steam is supplied.   The drying system according to claim 1, wherein the superheated steam supply unit stops the supply of the superheated steam when a predetermined stop condition is satisfied. A temperature measuring unit for measuring the temperature of the gas discharged from the bag filter;
The drying system according to claim 3, wherein the stop condition is that the temperature measured by the temperature measurement unit reaches a predetermined temperature threshold value. When supply of the superheated steam is stopped by the superheated steam supply unit,
The drying system according to claim 3 or 4, wherein the gas supply unit increases the supply amount of the gas by the supply amount of the superheated steam.   The said raw material injection | throwing-in part starts the injection | pouring of the said water-containing solid substance to the said fluidized bed furnace, when supply of the said superheated steam is stopped by the said superheated steam supply part. The drying system according to claim 1. A starting method of a drying system for forming a fluidized bed of hydrous solids in a fluidized bed furnace and drying the hydrous solids,
Supplying gas from the bottom of the fluidized bed furnace,
A method for starting a drying system, characterized in that superheated steam is added to the gas discharged from the fluidized bed furnace and supplied to at least a bag filter for filtering the gas.

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