JP5058567B2 - Fluidized drying method and fluidized bed drying apparatus - Google Patents

Description

  More particularly, the present invention relates to a fluid drying method and apparatus for moisture-containing coal for pretreatment of coke.

  The method using a fluidized bed drying device as a method for drying or classifying moisture-containing raw materials (substances to be dried) is easy to achieve uniform drying, the drying time can be shortened, and drying At the same time, it is widely used because it can be classified.

  However, it is often difficult to stabilize the fluidization state in this method, and in particular when the water to be dried has a high moisture content or the adherence of the material to be dried is high, the material to be dried is supplied from the supply port. Immediately after charging, there is a problem that the fluidized state deteriorates due to the phenomenon that the inner wall of the apparatus or the objects to be dried adhere and agglomerate.

  In order to solve the above problem, for example, Patent Document 1 discloses a method of controlling the flow rate / temperature of the fluidized bed blowing gas to control the fluidized state / classifying property, and further, in the vicinity immediately below the raw material inlet. It is described that a large mass discharging device is installed below the fluidized bed and discharged out of the system to obtain a stable fluidization.

  Patent Document 2 describes a method for improving the flow state by equalizing the pressure loss of a plurality of fluidized bed chambers in a circulating fluidized bed boiler or the like.

  Further, Patent Document 3 discloses a method of installing a stirring means below the vicinity of the supply port in order to prevent the flow from being hindered by drying of a processed product having a high water content.

  Further, in Patent Document 4, when coarse powder is discharged intermittently, the difference between the gas pressure immediately above the dispersion plate and the gas pressure of the free board is controlled to be a predetermined value to stabilize the flow state. It is disclosed to obtain

JP 2000-197854 A JP-A-8-35610 JP 2003-130545 A JP-A-6-343927

  Especially when drying and classifying particles with high moisture content or high adhesion due to moisture content using a fluidized bed drying device, drying is hardly progressing near the feed part of the raw material. Fluidization defects are likely to occur due to aggregation and adhesion to the apparatus.

  Therefore, if it is mild, there will be problems such as increased dispersion in drying / classification and dropping of raw materials under the dispersion plate. Then, due to clogging of the dispersion plate, etc., there arises a problem that fluidization becomes difficult and processing cannot be performed.

  As a method of drying a material having a large amount of water and adhesiveness using a fluidized bed, Patent Document 3 discloses that a stirrer is provided to crush and disperse the material. In addition to the increase in the flow rate, the flow at the stirrer is non-uniform and the flow of processed material from the supply unit to the discharge unit is non-uniform, resulting in large variations in residence time and large variations in dryness. There was a problem.

  Further, in Patent Document 1, it is disclosed that a large mass discharging device is installed in the vicinity of the supply unit to remove the large mass, but the purpose is to discharge the large mass contained in the raw material and perform stable fluidization. Therefore, there is no disclosure of a method for preventing a raw material rich in moisture from agglomerating.

  Further, Patent Document 2 discloses that the fluidized bed layer thickness of each chamber is made equal to make the pressure loss of a plurality of fluid chambers equal to improve the flow state, and Patent Document 4 discloses coarse powder. In the case of intermittent discharge, it is disclosed that the difference between the gas pressure immediately above the dispersion plate and the gas pressure of the free board is controlled to be a predetermined value to obtain a stable flow state, No measures have been taken to prevent agglomeration or improve the flow at a specific part in the vicinity of the supply unit.

  For this reason, there is a problem that due to poor fluidization in the vicinity of the supply section, the flow state of the entire fluidized bed becomes poor, the target drying / classification performance cannot be exhibited, and in some cases, the operation is stopped.

  In addition, in the case of a fluidized bed drying apparatus that has a classification function in addition to drying, it is necessary to set the flow rate of the free board part (classification part) according to the classification particle size, so that the upper limit of the fluidization gas input flow rate is Therefore, there is a limit to the stabilization of the fluid state by increasing the flow rate of fluidized gas.

  In view of the above problems, the present invention uses a fluidized bed drying apparatus to agglomerate raw material particles using a fluidized bed drying apparatus, or a raw material having a high water content (a material to be dried) or a water-containing adhesive material. It is an object of the present invention to provide a fluidized drying method and a fluidized bed drying device that can stably dry and classify while suppressing the occurrence of adhesion to the device.

As a result of intensive studies, the inventors divided the fluidized bed near the raw material supply port and the subsequent fluidized bed chambers, and controlled the thickness of the fluidized bed near the raw material supply port separately from the thickness of the subsequent fluidized bed. Thus, in particular, it has been found that the above problem can be solved by controlling the thickness of the fluidized bed in the vicinity of the raw material supply port to be smaller than the thickness of the subsequent fluidized bed, and has led to the present invention.
Its characteristics are as follows.

(1) A supply chamber having a raw material supply port and a dry classification chamber having a processed product discharge port are provided, and a raw material containing moisture is supplied to the supply chamber from the raw material supply port, and the fluid flows through a dispersion plate in each chamber. A continuous fluidized bed drying apparatus that discharges the coarsely processed material from the discharge port of the drying classification chamber after flowing the fluidized material with a chemical gas to dry and classify it into fine powder and coarse particles was used. In the fluidized drying method, the supply chamber and the drying classification chamber are separated by a partition plate installed from the ceiling of the fluidized bed drying device to above the dispersion plate, and the fluid to be fed into the supply chamber By adjusting the supply pressure of the forming gas, the pressure loss in the fluidized bed portion in the supply chamber is controlled to be smaller than the pressure loss in the fluidized bed portion in the subsequent drying classification chamber, whereby the flow of the supply chamber The layer thickness of the layer Controls thinner than the layer thickness of the flow layer of Grade chamber, fluidized drying method wherein the supply chamber, and wherein the suppressing agglomeration of attachment and the fluids into the supply chamber of the object to be fluids .
( 2 ) The fluidized drying method according to (1 ) , wherein the height of the dispersion plate in the supply chamber is higher than the height of the dispersion plate in the drying classification chamber.
( 3 ) The fluidized drying method according to (1) or (2) , wherein the fluidized material is coal for coke pretreatment.
( 4 ) The fluidizing gas pipe to be introduced into the supply chamber is provided with a pressure regulating valve and a flow regulating valve upstream thereof, and the flow rate and pressure of the fluidizing gas to be introduced are controlled by both regulating valves. The fluidized drying method according to any one of (1) to (3), wherein the fluidized drying method is adjusted.

(5) A supply chamber having a raw material supply port and a supply chamber wind box connected to the lower side via a dispersion plate, a drying classification chamber having a processed product discharge port, and a drying connected to the lower side via a distribution plate A fluidizing gas supply pipe for the supply chamber that has a classification chamber air box, a pressure adjustment valve, and a flow rate adjustment valve upstream thereof and is connected to the supply chamber air box, and is connected to the dry classification chamber air box The fluidizing gas supply pipe for the drying classification chamber, the pressure detection device for detecting the pressures of the supply chamber and the supply chamber wind box, and the differential pressure between the supply chamber and the supply chamber wind box , A pressure control valve, or a feedback control device that controls the pressure control valve and a flow rate control valve upstream of the pressure control valve so as to have a predetermined value smaller than a differential pressure between the dry classification chamber and the dry classification chamber wind box. The supply chamber and the drying classification chamber are the fluidized bed drying device. Fluidized bed drying apparatus characterized by being separated by the installed partition plate from the ceiling to above the dispersion plate.
(6) The fluidized bed drying apparatus according to (5), wherein the position of the dispersion plate below the supply chamber is set higher than the position of the dispersion plate below the drying classification chamber.

  According to the present invention, the fluidized bed in the vicinity of the raw material supply port is separated from the fluidized bed chamber thereafter, and the thickness of the fluidized bed in the vicinity of the raw material supply port is controlled separately from the thickness of the subsequent fluidized bed. A raw material that is abundant or adherent due to the inclusion of moisture can be stably dried using a fluidized bed dryer while suppressing the occurrence of adhesion and agglomeration. Furthermore, by controlling the thickness of the fluidized bed in the vicinity of the raw material supply port to be thinner than the thickness of the subsequent fluidized bed, it is possible to stably dry while suppressing the occurrence of adhesion and agglomeration.

  In the present invention, a supply chamber is provided in the vicinity of the raw material inlet of a fluidized bed dryer to which a raw material having a high moisture content (substance to be dried) is charged, and is separated from the subsequent drying classification chamber, and the flow of the supply chamber By controlling the layer thickness separately from the fluidized bed thickness of the drying classification chamber, the fluidized state in the vicinity of the raw material inlet can be improved. In particular, by making the fluidized bed thickness of the supply chamber thinner than the fluidized bed thickness of the drying classification chamber, the moisture content is still high and the material to be dried is prone to agglomeration and adhesion in the apparatus immediately after charging. However, the fluidized state is good, and agglomeration and adhesion in the apparatus can be suppressed and prevented.

  In addition, since the fluidized bed thickness used for the comparison between the supply chamber and the drying classification chamber in the present invention is a fluidized bed thickness that compares the two chambers relatively, the fluidized bed thickness during fluidization or the fluidized bed Either the thickness of the stationary fluidized bed at the time of stopping can be used, and when the fluidized bed thickness at the time of fluidization in the supply chamber is thicker than that in the drying classification chamber, the thickness of the stationary fluidized bed is similarly increased. If it is a static fluidized bed thickness, visual confirmation is also possible.

  In order to make the fluidized bed thickness of the supply chamber thinner than the fluidized bed thickness of the drying classification chamber, the pressure loss in the fluidized bed section (also referred to as fluidization section) in the supply chamber is reduced to the fluidized bed in the subsequent drying classification chamber. This can be achieved by controlling so as to be smaller than the pressure loss at the portion.

An embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram showing an example of a fluidized bed drying apparatus according to the present invention. In the present embodiment, the drying process is performed, and the dried raw material (substance to be dried) is also classified into fine powder and coarse particles.

  The fluidized bed body 10 is divided by a partition plate 11 into a supply chamber 19 having a raw material supply port 16 and a dry classification chamber 20 having a processed product discharge port 17. In the lower part of the supply chamber 19 and the drying classification chamber 20, air boxes 14a and 14b are installed via dispersion plates 12a and 12b, respectively. The wind box 14a and the wind box 14b are completely partitioned.

  The partition plate 11 is installed from the ceiling of the fluidized bed main body 10 to above the dispersion plate 12a. The gap between the lower portion of the partition plate 11 and the dispersion plate 12a is dried by the material to be dried from the supply chamber 19 on the dispersion plate. A space is kept so as not to prevent movement to the classification room 20. For example, it can be determined in consideration of the fluidized bed thickness to be set, such as 1/2 of the fluidized bed static layer thickness. However, the partition plate 11 is preferably movable in order to check the actual flow state and optimize it. For example, a part of the movable plate provided with the lower long hole is overlapped with the upper fixed plate. The gap can be made variable by bolting or the like.

  Although the drying classification chamber 20 is one room in the figure, it may be a multi-stage multiple room, for example, when classification is performed in multiple stages.

  A fluidizing gas supply pipe 25a having a pressure regulating valve 26a and a flow rate regulating valve 27a on the upstream side thereof is connected to the wind box 14a, and a fluidizing gas supply pipe 25b having a flow regulating valve 27b is connected to the wind box 14b. The fluidized gas 40 that is connected and generated in the hot air generating furnace 32 is supplied to the fluidized bed. In the hot air generating furnace 32, air or the like is supplied from the fluidizing gas supply blower 33, and the temperature adjustment device 34 performs TIC control so that the temperature of the temperature detection device 35 becomes a predetermined temperature.

  The position of the dispersion plate can be the same in the dispersion plate 12a in the lower part of the supply chamber and the dispersion plate 12b in the lower part of the drying classification chamber, but the position of the dispersion plate 12a is arranged higher than the position of the dispersion plate 12b. Then, since it is easy to make the fluidized bed thickness 13a of a supply chamber thin, it is preferable. More preferably, the dispersion plate is arranged so that the static fluidized bed layer thickness 13a of the supply chamber is ½ to ３ of the static fluidized bed layer thickness 13b of the drying classification chamber.

  Free board portions (classifying portions) 15a and 15b having a cross-sectional area larger than that of the fluidized bed portion are provided at the upper portions of the supply chamber 19 and the drying classification chamber 20, respectively.

  Discharge pipes 21a and 21b for discharging the fluidized gas exhaust gas from the supply chamber 19 and the dry classification chamber 20 and fine powder accompanying the exhaust gas are connected to the free board sections. In the middle of the respective discharge pipes 21a and 21b, fine powder separators 22a and 22b such as a cyclone for separating the fine powder accompanied with the exhaust gas are installed. The exhaust gas after the fine powder is recovered is discharged out of the system by the exhaust gas blower 24.

  Pressure detectors 30a and 29a such as a pressure gauge for detecting fluidizing gas pressure are installed above the wind box 14a and the supply chamber 19 below the supply chamber, respectively. Pressure detectors 30b and 29b such as pressure gauges are also installed above the wind box 14b and the drying classification chamber 20 below the drying classification chamber. Since these pressure detection devices are for measuring the pressure loss of the fluidized bed, the pressure detection device 29a above the supply chamber 19 and the pressure detection device 29b above the drying classification chamber 20 are to be dried. It is preferable to install it above the fluidized bed portion of the product. You may install in free board part 15a, 15b.

  The pressure detection devices 30a and 29a and the pressure detection devices 30b and 29b are each replaced with a differential pressure gauge (not shown), and measure the pressure loss of each fluidized bed portion in the supply chamber 19 and the drying classification chamber 20, respectively. Is also possible.

  A feedback control device 31 is arranged outside the fluidized bed main body 10 and takes in pressure data detected by the pressure detection devices 30a and 29a or measurement data of a differential pressure gauge, and a pressure difference between the pressure detection devices 30a and 29a. That is, feedback control is performed by adjusting the pressure adjustment valve 26a, or the pressure adjustment valve 26a and the flow rate adjustment valve 27a so that the pressure loss in the fluidized bed portion becomes a preset value. In addition, without providing a feedback control mechanism, based on the pressure data detected by the pressure detection devices 30a and 29a or the measurement data of the differential pressure gauge, the pressure loss of the fluidized bed portion becomes a preset value by the operator. As described above, it is possible to manually control the pressure regulating valve 26a and the like, but it is preferable to perform automatic control by feedback control or the like.

  The raw material containing moisture that can be applied to the present invention (substance to be dried) is not limited as long as it is a granular material having a fluidizable particle size. For example, the moisture used as a raw material for coke for coke pretreatment About 10% or more of coal can be used.

  The raw material is continuously supplied from the raw material supply port 16, falls onto the upper part of the fluidized bed in the supply chamber 19, is immediately mixed into the fluidized bed, and the particle surface is dried by the fluidized gas 40 which is hot air.

  In the raw material, fine powder having a small particle diameter is partly accompanied by the exhaust gas of the fluidizing gas 40 from the supply chamber, discharged through the discharge pipe 21a, and collected by the fine powder separator 22a. At this time, particles having a terminal velocity smaller than the gas flow velocity (relatively small particle size) with respect to the gas flow rate of the free board portion 15a above the supply chamber 19 are discharged along with the exhaust gas, and the terminal velocity is the gas flow rate. Particles larger than the flow rate (relatively large particle size) remain in the supply chamber 19 without being discharged.

  The coarse particles and a part of the fine powder move from the supply chamber 19 toward the drying classification chamber 20 while being fluidized, and are further dried in the drying classification chamber 20 to dry not only the particle surface but also the inside of the particles. Also in the dry classification chamber 20, depending on the particle size, the freeboard portion is accompanied by the exhaust gas of the fluidized gas 40 and discharged through the discharge pipe 21b and is collected by the fine powder separator 22b.

  The dried coarse particles are discharged from the processed material discharge port 17. When the discharge port 17 is installed at a position lower than the static fluidized bed thickness, a weir 18 is provided on the outlet side of the drying classification chamber 20 as shown in the figure to maintain the fluidized bed thickness of the drying / classification chamber. Is preferred.

  It is desirable to provide a rotary valve or a screw feeder or the like that can maintain confidentiality in the fluidized bed and control the passage amount downstream of the processed material discharge port 17. For the same reason, it is desirable to provide a rotary valve or a screw feeder upstream of the raw material supply port 16.

  The cross-sectional area of the free board parts 15a and 15b on the fluidized bed is larger than the cross-sectional area of the fluidized bed part, and the upper part is enlarged so that the gas flow rate of the free board parts 15a and 15b is suitable for the target classification particle size. Speed.

  The free board portions 15a and 15b are preferably set to a value close to atmospheric pressure in order to suppress gas ejection and suction from the raw material supply port 16 and the processed product discharge port 17. As pressure control means therefor, pressure detection devices 29a and 29b provided in the free board portions 15a and 15b, respectively (in this embodiment, the pressure detection device that detects the gas pressure in the fluidized bed portion) and pressure adjustment For example, the pressure may be controlled separately in the supply chamber 19 and the drying classification chamber 20 by the valves 23a and 23b.

  FIG. 2 shows the relationship between the pressure loss in the fluidized bed portion (the difference between the pressures detected by the pressure detection devices 30 a and 29 a) and the fluidized bed stationary layer thickness in the supply chamber 19. The parameter is the gas flow rate (Bm / s) in the fluidized bed portion of the supply chamber. It can be seen that the stationary layer thickness is proportional to the pressure loss in the fluidized bed portion. Since the pressure in the pressure detection device 29a can be adjusted to be almost atmospheric pressure, it can be seen that the static layer thickness is actually proportional to the pressure in the wind box 12a. That is, the fluidized bed static layer thickness can be controlled by adjusting the wind box pressure.

  The relationship in FIG. 2 is the same in the dry classification chamber. The pressure loss of the fluidized bed portion in the dry classification chamber 20 (the difference in pressure detected by the pressure detection devices 30b and 29b) and the fluidized bed portion of the supply chamber 19 are the same. By comparing the pressure loss and controlling the pressure loss in the fluidized bed portion of the supply chamber 19 to be small, the fluidization state of the supply chamber in the vicinity of the raw material inlet can be improved, and agglomeration and Adhesion to the inside of the apparatus can be prevented.

  In addition, the flow rate of the fluidizing gas 40 is such that the superficial velocity of the fluidized bed portions of the supply chamber 19 and the drying classification chamber 20 is maintained above the minimum fluidization velocity of the target particles to maintain a good fluidization state, and The flow rates of the free board portions 15a and 15b are controlled so as to be within a range in which a predetermined value (the end velocity of the particle classification point) is obtained. The flow rate control of the supply chamber 19 is controlled by the feedback control device 31 so that the fluidized gas flow rate detected by the flow rate detection device 28a becomes a predetermined value, and the flow rate control of the drying classification chamber 20 is detected by the flow rate detection device 28b. FIC control is performed by the flow rate adjusting valve 27b so that the flow rate of the fluidized gas becomes a predetermined value.

  Here, since the fluidization state of the dry classification chamber 20 is stable, once the flow rate and pressure in the fluidized bed portion of the dry classification chamber 20 are set by the flow rate adjustment valve 27b and the pressure adjustment valve 23b, further Since there is little necessity for control, the flow rate and pressure in the fluidized bed portion of the supply chamber 19 are adjusted by the flow rate regulating valve 27a and the pressure regulating valves 26a and 23a, and the fluidized bed thickness of the feeding portion is adjusted in the dry classification unit. What is necessary is just to make it smaller than the fluidized bed thickness. Since the pressure in the upper portion of the supply chamber can be controlled by 23a, in practice, the fluidized bed thickness may be controlled by the flow rate adjusting valve 27a and the pressure adjusting valve 26a. Furthermore, when the flow rate is stable, the fluidized bed thickness can be controlled only by the pressure regulating valve 26a.

  Among these controls, the flow rate adjustment valve 27a and the pressure adjustment valve 26a are controlled by the feedback control device 31, and the other valves may be controlled by independent PICs and FICs of the respective valves.

Using the apparatus shown in FIG. 1, a test was performed in which coal having a moisture content of 12% (moisture mass / coal mass−wet × 100) was dried and classified. The thickness of the stationary fluidized bed was 100 mm in the supply chamber 19 and 300 mm in the dry classification chamber 20, and the particle size at the classification point was 0.5 mm.
Coal having a particle size distribution of 0.1 mm to 4.5 mm was used.

  The main body of the fluidized bed drying classification apparatus is an apparatus having a dimensional ratio of 1: 3 in the longitudinal direction (lateral direction in the drawing) of the supply chamber 19 and the drying classification chamber 20 (cross-sectional area of the free board portions 15a and 15b) / (flowing). The cross-sectional area of the layer portions 13a and 13b) is an apparatus in which both the supply chamber 19 and the drying classification chamber 20 are 2.4 times.

  The flow rate of the fluidized gas 40 is equal to or higher than the minimum fluidization speed (4.0 m / s) at which the flow velocity in the fluidized bed is the maximum particle size (4.5 mm), and the particle size at the classification point (0.5 mm) in the free board portion In the fluidized bed portion of the supply chamber 19 and the drying classification chamber 20, both were controlled to be 4.0 Bm / s.

The fluidizing gas 40 was set to 300 ° C. at the inlet temperature of the wind boxes 14a and 14b.
The height of the dispersion plate 12a below the supply chamber 19 was set to be 200 mm higher than the dispersion plate 12b below the drying classification chamber 20.
The gap between the partition plate 11 and the dispersion plate 12a was 50 mm.

The pressure in the upper part of the fluidized bed (in the example, the pressure in the free board part) is slightly positive with respect to atmospheric pressure to suppress air suction from the raw material supply port and coarse powder outlet and hot air blowing from the fluidized bed. The pressure was controlled to 5 mmH ₂ O.

Under the above test conditions, when raw coal was continuously charged and tested, the pressure from the pressure detector 30a of the wind box 14a at the lower part of the supply chamber was controlled to 135 mmH ₂ O (pressure loss 130 mmH ₂ O in the fluidized bed portion). By controlling the pressure from the pressure detection device 30b of the wind box 14b in the lower part of the drying classification chamber to 275 mmH ₂ O (pressure loss of the fluidized bed portion 270 mmH ₂ O), the thickness of the stationary fluidized bed of the supply chamber 19 can be set as intended. 100 mm, the thickness of the fluidized bed in the drying classification chamber 20 could be 300 mm.

At that time, the flow state of the supply chamber 19 is good, and the fine powder collected by the fine powder classifiers 22a and 22b made of cyclone is approximately 95% with a ratio of 0.5 mm or less, and the processed product discharge port. The processed product discharged from No. 17 was not agglomerated, the moisture content was 2%, and both drying and classification could be processed without problems.
After completion of the test, the fluidized bed drying apparatus main body 10 was opened and the inside of the apparatus was visually observed. Almost no coal was found inside the apparatus.

As a comparative example, except that the dispersion plates 12a and 12b have the same height, and the gas pressure in the wind boxes 14a and 14b (the detection pressure of the pressure detection devices 30a and 30b) is both controlled to 290 mmH ₂ O. When the test was performed under the same conditions as in the example, the flow state of the supply chamber 19 was not stable, and the agglomerated material was mixed in the processed material discharged from the processed material discharge port 17. The pressure in the air box 14a can no longer be controlled. When the apparatus main body 10 was opened and inspected after the test, the agglomerated material to be dried was deposited on the dispersion plate 12a in the supply chamber 19, and dropped to the wind box 14a below the dispersion plate 12a. The dispersion plate 12a was also partially clogged. The same phenomenon occurred in the dry classification chamber 20 although it was small.

It is the figure which showed one Embodiment of this invention. It is the figure which showed the relationship between the pressure loss of a fluidized bed part, and the fluidized bed stationary layer thickness.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Main body 11 Partition plate 12a, 12b Dispersion plate 13a, 13b Fluidized bed part 14a, 14b Air box 15a, 15b Free board 16 Raw material supply port 17 Processed material discharge port 18 Weir 19 Supply chamber 20 Drying / classification chamber 21a, 21b Exhaust gas Fine powder discharge pipes 22a, 22b Fine powder classifiers 23a, 23b Pressure adjusting valve 24 Exhaust gas blowers 25a, 25b Fluidized gas supply pipe 26a Pressure adjusting valves 27a, 27b Flow adjusting valves 28a, 28b Flow rate detecting devices 29a, 29b Pressure detecting devices 30a, 30 b Wind box pressure detection device 31 Feedback control device 32 Hot air generator 33 Fluidized gas supply blower 34 Fluidized gas temperature control device 35 Temperature detection device 40 Fluidized gas

Claims (6)

A supply chamber having a raw material supply port and a dry classification chamber having a processed product discharge port are provided, a raw material containing moisture is supplied to the supply chamber from the raw material supply port, and fluidized gas is passed through a dispersion plate in each chamber. A fluidized drying method using a continuous fluidized bed drying apparatus that discharges the coarsely processed material from an outlet of the dry classification chamber after flowing the material to be dried and classifying it into fine powder and coarse particles Because
The supply chamber and the drying classification chamber are separated by a partition plate installed from the ceiling of the fluidized bed drying device to above the dispersion plate,
By controlling the supply pressure of the fluidizing gas introduced into the supply chamber, the pressure loss in the fluidized bed portion in the supply chamber is controlled to be smaller than the pressure loss in the fluidized bed portion in the subsequent drying classification chamber. And controlling the layer thickness of the fluidized bed in the supply chamber to be smaller than the layer thickness of the fluidized bed in the drying classification chamber ,
A fluidized drying method characterized by suppressing adhesion of a material to be supplied to the supply chamber and agglomeration of the material to be fluidized in the supply chamber . Fluidized drying method according to claim 1, characterized in that the height of the supply chamber of the dispersion plate, arranged higher than the height of the dispersion plate of the dry classification chamber. The fluidized drying method according to claim 1 or 2 , wherein the material to be fluidized is coal for coke pretreatment. The fluidizing gas piping to be introduced into the supply chamber has a pressure regulating valve and a flow regulating valve upstream thereof, and the flow rate and pressure of the fluidizing gas to be introduced are regulated by both regulating valves. The fluidized drying method according to any one of claims 1 to 3 . A supply chamber having a raw material supply port and a supply chamber wind box connected to the lower side via a dispersion plate, a drying classification chamber having a discharge port, and a drying classification chamber wind box connected to the lower side via a dispersion plate A fluidizing gas supply pipe for the supply chamber that has a pressure adjustment valve and a flow rate adjustment valve upstream thereof and is connected to the supply chamber air box; and the drying classification chamber connected to the drying classification chamber air box Fluidizing gas supply piping, a pressure detecting device for detecting the pressure of the supply chamber and the supply chamber wind box, and a differential pressure between the supply chamber and the supply chamber wind box, the drying classification chamber and the pressure chamber A pressure control valve that controls the pressure control valve or the pressure control valve and a flow rate control valve upstream of the pressure control valve so as to have a predetermined value that is smaller than the differential pressure with the dry classification chamber wind box ; The drying classification chamber is from the ceiling of the fluidized bed drying device. Fluidized bed drying apparatus characterized by being separated by a partition plate disposed to above the serial distribution plate. 6. The fluidized bed drying apparatus according to claim 5 , wherein the position of the dispersion plate below the supply chamber is set higher than the position of the dispersion plate below the drying classification chamber.

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