JPH09201571A - Fluidized bed classifier - Google Patents

Abstract

PROBLEM TO BE SOLVED: To classify efficiently while a fluidized bed being formed stably. SOLUTION: The cross-sectional area of the upper space in a container 4 in which a fluidized bed 9 is formed can be adjusted by swinging and displacing a movable plate 16. The fluidized bed 9 is formed stably by air supplied from a blower 5 to a wind box 2, and classification can be done efficiently by changing the cross-sectional area of a free board part. Coarse powder of large particle size is discharged from the fluidized bed 9 through a coarse powder discharge opening 12, and fine powder of small particle size is discharged from a fine powder outlet 10 to be recovered by a dust collector 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluidized bed classifier for separating powdery and granular materials such as fine aggregate, rubble and coal in accordance with the particle size by using a fluidized bed, and more particularly, to a method of drying the processed material. The present invention relates to a fluidized bed classifier capable of classifying.

[0002]

2. Description of the Related Art The prior art of a fluidized bed classifier is disclosed, for example, in Japanese Patent Laid-Open No. 6-343927. Conventional classification processing is performed using a sieve and wind power. The size of the sieve is determined by the size of the mesh,
Those with fine eyes are easily clogged. For this reason, it is practically suitable for classification of particle diameters of 1 mm or more. The use of wind power is represented by a cyclone that is rotated and separated by centrifugal force, and is practically suitable for classification of particles having a particle size of 100 μm or less. JP-A-6-3439
Fluid bed classifier as disclosed in No. 27 is 100 μm
It is also applicable to the classification of particles in the range of １1 mm. In order to improve the classification efficiency, not only adjust the flow rate of the gas to be blown to form the fluidized bed, but also narrow the cross-sectional area of the fluidized bed formation part from the space above it, and determine the particle size to be classified The flow velocity of the gas for forming the fluidized bed is increased more than the superficial velocity of the free board portion, and the fluidized bed can be formed for particles having a wide range of particle diameters.

[0003]

The powdery and granular material such as fine aggregate, rubble, and coal is formed through a mechanical pulverization process, and is sprayed with water to prevent the powder from spreading as dust during the pulverization. Is often done. In the post-treatment of rubble, for example, waste materials from houses damaged by an earthquake or the like, water is applied so that dust is not generated in the process of turning incombustible materials into fine aggregate after burning inflammable materials. These powdery processed products need to be dried before classification. Further, it is preferable that the coal to be charged into the coke oven for iron making is classified together with the drying to adjust the particle size. If the classification of the powdery and granular material is performed using a fluidized bed classifier and fluidization is performed using a high-temperature gas, the classification can be performed while drying in a fluidized bed.

[0004] However, in order to dry a processed product, a predetermined amount of hot air and a drying time are required for drying, and it is not preferable to change the cross-sectional area of the fluidized bed. Further, there is a possibility that the granular material accumulates on the upper part of the mechanism for changing the cross-sectional area of the fluidized bed, and smooth movement is impaired or stopped.

[0005] An object of the present invention is to provide a fluidized bed classifier capable of classifying powdery and granular processed products more efficiently. It is a further object of the present invention to provide a fluidized bed classifier capable of efficiently performing drying together with classification.

[0006]

The present invention utilizes a fluidized bed formed above a dispersion plate by fluidizing a powdery or granular material to be processed through a charging port with a gas blown from below the dispersion plate. In the fluidized bed classifier that classifies the processed material according to the particle size of the processed material and discharges the processed material of a predetermined particle size from the discharge port, the cross sectional area varying means capable of changing the cross sectional area of the freeboard portion above the fluidized bed. The fluidized bed classifier is characterized by including. According to the present invention, since it is possible to change the cross-sectional area of the freeboard portion above the fluidized bed by the cross-sectional area varying means, the conditions for forming the fluidized bed are not changed, and the gas in the freeboard portion is not changed. The classification particle diameter can be made variable by changing the flow rate, and efficient classification can be performed.

Further, the present invention is characterized in that a heating means for heating the gas for forming the fluidized bed and drying the processed product is provided. According to the present invention, the gas that forms the fluidized bed is heated by the heating means, and the processed product can be dried. Therefore, the processed product is dried in the fluidized bed, and the powder dried using the fluidized bed is dried. Grain classification can be performed efficiently.

In the present invention, the inside of the vessel in which the fluidized bed is formed is divided into a plurality of chambers by a partition plate. According to the present invention, since the inside of the container in which the fluidized bed is formed is divided into a plurality of chambers, classification is performed by changing the classification particle size for each chamber, and sufficient drying is performed by increasing the thermal efficiency in the fluidized bed. Can be performed.

The present invention is also characterized by including distribution adjusting means for adjusting the flow distribution of the gas blown into the plurality of chambers and forming the respective fluidized beds. According to the present invention, it is possible to form a plurality of chambers and adjust the flow rate distribution of the gas blown into each chamber to form a fluidized bed. Therefore, efficient classification and drying can be performed.

In the present invention, the cross-sectional area varying means has a movable portion on at least a part of the partition plate. According to the present invention, since at least a part of the partition plate has a movable part, the ratio of the relative cross-sectional areas of the plurality of chambers is changed by moving the movable part, and the flow velocity of the gas in the freeboard part is changed. It can be changed to adjust the classified particle size.

Further, in the present invention, the cross-sectional area varying means has a movable wall inside at least a part of a side wall surface forming a chamber in a container in which a fluidized bed is formed. According to the present invention, since the movable wall is provided inside at least a part of the side wall surface forming the chamber in the container in which the fluidized bed is formed, the movable wall is moved and the cross-sectional area of the freeboard portion above the fluidized bed is reduced. The flow velocity can be changed by decreasing the cross-sectional area to increase the flow velocity or increasing the cross-sectional area to decrease the flow velocity.

According to the present invention, the movable wall has a substantially rectangular shape and is swingably displaceable with the lower side as an axis. According to the present invention, the movable wall provided inside at least a part of the side wall forming the chamber in the container in which the fluidized bed is formed has a substantially rectangular shape, and can be oscillated and displaced about the lower side as an axis. Is. Since the lower side near the fluidized bed is the swing axis, even if the cross-sectional area of the freeboard part is changed by the movement of the movable wall, the cross-sectional area of the part near the fluidized bed hardly changes and the formation of the fluidized bed is stabilized. It can be carried out.

Further, the present invention is characterized in that there is provided a discharge means for discharging the processed material deposited in the space between the movable wall and the outer side wall surface. According to the present invention, in the space between the movable wall and the side wall surface in which the movable wall is provided, in the course of the fluidization treatment for a long period of time, it is avoided that a part of the processed material enters and accumulates. I can't. Since the deposited material can be discharged by the discharging means, the movable wall can be reliably moved for a long period of time.

The container in which the fluidized bed is formed according to the present invention is provided with an inlet for introducing the processed material on one side surface, and an outlet for discharging the classified processed material on the side surface opposite to the one side surface. Is provided, and the movable wall is provided on at least a part of the remaining side surface. According to the present invention, since the movable wall is provided inside the one side surface provided with the inlet and the side surface different from the other side provided with the discharge port, it is possible to perform uniform flow velocity adjustment as a whole. .

Further, in the container in which the fluidized bed is formed in the present invention, an inlet for introducing the processed material is provided on one side surface, and an outlet for discharging the classified processed material on the side surface opposite to the one side surface. And the movable wall are provided. According to the present invention, since the movable wall is provided inside the wall surface on the discharge port side, it is possible to perform efficient classification mainly on the powder / granular material in the fluidized bed portion immediately before being discharged.

Further, the present invention is characterized by comprising a large-volume discharging means provided at the bottom of the dispersion plate near the charging port. According to the present invention, even if large lumps having a particle size large enough to form a fluidized bed in the processed material are mixed, since the large lumps discharging means is provided at the bottom of the dispersion plate near the inlet. In addition, it is possible to prevent the large lump from spreading on the dispersion plate and hindering fluidization.

[0017]

FIG. 1 shows a schematic configuration of a fluidized bed classifier 1 according to a first embodiment of the present invention. FIG.
1A shows a front sectional view, and FIG. 1B shows a side sectional view. An air box 2 is provided below the fluidized bed classifier 1, and a dispersion plate 3 is provided above it. A container 4 is arranged above the dispersion plate 3. The flow rate of the air supplied from the blower 5 is adjusted by the air volume adjustment damper 6, and the air is pushed into the wind box 2 from the air outlet 7. The air pushed into the wind box 2 is blown upward from a large number of air channels formed in the dispersion plate 3 and blown into a single chamber 4 a in the container 4. The processed material to be classified is charged into the chamber 4a from the raw material charging port 8. The processed material is fluidized by air blown from below the dispersion plate 3, and a fluidized bed 9 is formed in a space above the dispersion plate 3.

The treated material is fluidized when the air flow rate is higher than the fluidization start speed determined according to the particle size and specific gravity. When the terminal velocity, which is predetermined according to the particle size or specific gravity of the particles, becomes larger than the flow velocity of the gas in the fluidized bed, the particles cannot stay in the fluidized bed 9 but jump out of the fluidized bed 9. Generally, large and heavy particles have a high terminal velocity, and small and light particles have a low terminal velocity. Therefore, the particles can be classified into particles remaining in the fluidized bed and particles jumping out of the fluidized bed. The fine powder that has flowed out of the fluidized bed 9 is in the fine powder outlet 1
The gas is discharged together with the gas from 0 and collected by a dust collecting device 11 such as a cyclone. The coarse powder discharged from the fluidized bed 9 can be discharged from the coarse powder discharge port 12. The coarse powder discharge port 12 is provided with a sealing means for keeping the inside of the fluidized bed classifier 1 airtight, but is not shown.

The horizontal cross-sectional shape of the container 4 is substantially rectangular, and the input surface 13 where the raw material input port 8 is provided and the discharge surface 14 where the coarse powder discharge port 12 is provided opposite the input surface 13.
Is almost vertical. The side wall surfaces 15 are inclined outward so that the cross-sectional area increases as going upward. A movable plate 16 serving as a cross-sectional area varying means is arranged inside the side wall surface 15. The movable plate 16 is generally rectangular, and a swing shaft 17 is provided for its variable. The movable plate 16 is swingably displaceable about a swing shaft 17, and a seal member 18 is provided on an upper side.

A space is formed between the movable plate 16 and the side wall surface 15. Movable plate 16 and loading surface 13 and discharging surface 1
4 or a gap between the sealing member 18 on the upper part of the movable plate 16 and the ceiling of the container 4, a part of the processing object scattered from the fluidized bed 9 is moved to the vicinity of the swing shaft 17. Deposit little by little. In order to discharge sediment as necessary,
A deposit discharge chute 19 is provided. by this,
The processed material that accumulates when performing the classification process over a long period of time,
It can be reliably discharged to the outside of the container 4.

FIG. 2 shows the structure of the seal between the upper side of the movable plate 16 and the ceiling of the container 4. As shown in FIG.
When the ceiling plate 20a of the container 4 is flat, the distance between the upper side of the movable plate 16 and the ceiling plate 20a changes with the swinging displacement of the movable plate 16, so that a flexible rubber plate or the like is used. It is preferable to dispose the member 18 at the tip of the movable plate 16 to prevent the processing object from leaking from the gap between the movable plate 16 and the ceiling plate 20a. 2B, the ceiling plate 20b of the container 4 has an arc shape, and the upper side of the movable plate 16 and the ceiling plate 2 are
A configuration is shown in which the distance between the movable plate 16 and the movable plate 16 does not change even when the movable plate 16 is displaced by swinging, and the gap is made as small as possible to prevent the leakage of the processing object. Even if the seal member 18 as shown in FIG. 2A is provided, the gap cannot be completely sealed, and even if a slight leak occurs, the movable plate 16 cannot be used for a long period of time.
It is unavoidable that they accumulate in the space between the side walls 15. However, by performing sealing, leakage can be reduced and classification efficiency can be improved.

FIG. 3 shows a schematic configuration of a fluidized bed classifier 21 according to a second embodiment of the present invention. In the present embodiment, parts corresponding to the embodiment of FIG.
Description is omitted. A single chamber 22a is formed in the vessel 22 of the fluidized bed classifier 21, and its discharge surface 23 has an inclined surface 24 on the upper side, and a vertical surface corresponding to the portion where the fluidized bed 9 is formed. 25. The movable plate 16 is provided inside such a discharge surface 23, and the swing axis is provided near the boundary between the inclined surface 24 and the vertical surface 25. Since the cross-sectional area of the freeboard portion is changed by the movable plate 16 above the discharge port 12, the particle size of the coarse powder discharged from the coarse powder discharge port 12 can be efficiently adjusted.

FIG. 4 shows a schematic configuration of a fluidized bed classifier 31 according to a third embodiment of the present invention. In this embodiment,
1 and 3 are denoted by the same reference numerals and description thereof is omitted. The fluidized bed classifier 31 includes the wind box 32 and the dispersion plate 33 together with the wind box 2 and the dispersion plate 3.
And the interior of the container 34 is divided into two chambers 34a and 34b by a movable partition plate 35. The movable partition plate 35 is substantially rectangular, and a swing shaft 36 is provided on a lower side thereof. By swingingly displacing the movable partition plate 35, the ratio of the sectional area of the two chambers 34a and 34b divided in the container 34 can be changed.

Gas is supplied to each of the chambers 34a and 34b from the air outlet 7 of the wind box 2 and the air outlet 37 of the wind box 32, respectively. A sealing member 38 is provided on the upper side of the movable partition plate 35, and seals the ceiling of the container 34. Above the dispersion plate 3 and the dispersion plate 33, the wind box 2 and the wind box 32
Fluidized bed 9 and fluidized bed 39
Are respectively formed. The fluidized bed 9 fluidizes the raw material supplied from the raw material input port 8, and a flow port 35b below a fixed partition 35a provided below the movable partition 35.
Then, a part of the fluidized bed 9 moves to the fluidized bed 39 side, and coarse powder is discharged from the coarse powder discharge port 12. On the ceiling of the container 34,
A fine powder outlet 10 and a fine powder outlet 40 are provided for each of the chambers 34a and 34b, respectively.
Fine powder scattered from 9 is discharged respectively.

FIGS. 5 and 6 show a schematic configuration of a fluidized bed classifier 41 according to a fourth embodiment of the present invention. FIG.
Shows a side sectional view, and FIG. 6 shows a front sectional view. In the present embodiment, portions corresponding to the first to third embodiments are denoted by the same reference numerals, and description thereof is omitted. In the fluidized bed classifier 41, the container 42 is divided into two chambers 42a and 42b, and the inclined side wall surface 15 is provided in one chamber 42b. A movable wall 16 is provided inside the inclined side wall surface 15 so that the cross-sectional area of the freeboard portion can be changed. An opening 44 is provided in the lower part of the middle partition plate 43 that partitions the inside of the container 42, and a part of the fluidized bed 9 on the side where the raw material inlet 8 is provided is fluidized bed 39 on the side where the coarse powder outlet 12 is provided.
Can be transferred to.

Hot air from a hot air generator 45 is supplied to the wind box 2 and the wind box 32. The supplied hot air is distributed and adjusted by the air volume adjustment damper 6 and the air volume adjustment damper 46, and is supplied to the wind box 2 and the wind box 32 at, for example, 50:50 to 75:25. On the wind box 2 side, drying of the raw material supplied from the raw material charging port 8 is mainly performed, and on the fluidized bed 39 side, classification of the dried raw material is mainly performed. In order to perform classification efficiently, the cross-sectional area of the free board portion is changed.

When a large lump is mixed in the raw material supplied from the raw material charging port 8, the large lump is discharged from a large lump discharge chute 50 provided near the bottom plate of the dispersion plate 3. Classification air ports 51 and 52 are arranged in the large chute discharge chute 50 at intervals in the longitudinal direction, and air is blown near the position of the dispersion plate 3 so as to be at or above the coarse particle fluidization start speed. The large lumps that have once entered the large lumps discharge chute 50 are configured such that the flow velocity decreases inside the chute, so that the large lumps do not flow out again into the fluidized bed 9 and can be reliably collected. Hot air generator 45
The large lump discharge chute 50 can be similarly used in the first to third embodiments. In addition, although air is used for fluidization, other gases such as a reactive gas and an inert gas that promote or suppress a chemical reaction can be used as needed.

[0028]

As described above, according to the present invention, the freeboard cross-sectional area can be changed by the cross-sectional area changing means, so that even in the range where the air volume cannot be adjusted to control the particle size, the freeboard can be efficiently used. The classified particle size or the classification rate can be adjusted.

Further, according to the present invention, since the gas to be fluidized can be heated by the heating means, drying can be performed while fluidizing the processed product. When drying the processed material, the degree of drying is controlled by the temperature of hot air, and the amount of hot air is not changed even if the input amount of the processed material or the inlet moisture changes, and the particle size is controlled by adjusting the cross-sectional area of the free board. It can be carried out.

According to the present invention, since a plurality of chambers are formed in the container, fluidization is promoted in a chamber provided with an inlet, and classification is promoted in a chamber provided with an outlet. Conditions can be set and efficient classification can be performed. In particular, when the processed material contains moisture and needs to be dried, in the room provided with the charging port, conditions can be set so as to emphasize fluidization rather than classification, and efficient drying can be performed.

Further, according to the present invention, since it is possible to adjust the air flow distributions of a plurality of chambers, it is possible to perform efficient classification by dividing the conditions suitable for fluidization and the conditions suitable for classification for each chamber. You can

Further, according to the present invention, since at least a part of the partition plate divided into a plurality of chambers has a movable portion, the movable portion can be moved to easily change the ratio of the cross-sectional area between the chambers. it can.

Further, according to the present invention, since the movable wall is provided inside at least a part of the side wall surface forming the chamber of the container in which the fluidized bed is formed, the movable wall is moved to reduce the cross-sectional area of the freeboard portion. It can be changed easily.

Further, according to the present invention, since the movable wall has a substantially rectangular shape and is capable of swinging displacement about the lower side as an axis, the cross-sectional area near the portion where the fluidized bed is formed is stable and stable. A fluidized bed can be maintained.

Further, according to the present invention, the processed material deposited in the space between the movable wall and the outer side wall can be carried out by the discharging means, so that the change in the smooth sectional area can be stably performed for a long period of time. It can be carried out.

Further, according to the present invention, the cross-sectional area of the freeboard portion above the fluidized bed can be uniformly changed, and stable fluidized bed formation and classification can be performed.

Further, according to the present invention, since the cross-sectional area of the freeboard portion above the fluidized bed is changed on the side surface where the discharge port is provided, it is possible to improve the classification efficiency of the discharged processed material.

Further, according to the present invention, since the large lumps mixed with the processed material can be discharged by the large lumps discharging means, the processed material mixed with the large lumps which cannot be fluidized can be stably classified. Can be done.

[Brief description of drawings]

FIG. 1 is a front sectional view and a side sectional view showing a schematic configuration of a first embodiment of the present invention.

FIG. 2 is a partial cross-sectional view showing a sealing structure between a ceiling portion of a container 4 and a movable plate 16 in FIG.

FIG. 3 is a side sectional view showing a schematic configuration of a second embodiment of the present invention.

FIG. 4 is a side sectional view showing a schematic configuration of a third embodiment of the present invention.

FIG. 5 is a side sectional view showing a schematic configuration of a fourth embodiment of the present invention.

FIG. 6 is a front sectional view of a fourth embodiment of the present invention.

[Explanation of symbols]

 1,21,31,41 Fluidized bed classifier 2,32 Wind box 3,33 Dispersion plate 4,22,34,42 Container 5 Blower 6,46 Air flow control damper 8 Raw material inlet 9,39 Fluidized bed 10,40 Fine powder Discharge port 11 Dust collector 12 Coarse powder discharge port 13 Input surface 14 Discharge surface 15 Side wall surface 16 Movable plate 17, 36 Swing shaft 18, 38 Seal member 19 Sediment discharge chute 20a, 20b Ceiling plate 35 Movable partition plate 43 Middle divider 50 Large chute discharge chute

Claims (11)

[Claims] 1. A powder-granular processed material charged from an input port is fluidized by a gas blown from below the dispersion plate, and a fluidized bed formed above the dispersion plate is used to adjust the particle size according to the particle size of the processed material. A fluidized bed classifier that classifies and discharges a processed material having a predetermined particle size from an outlet, characterized by including a cross-sectional area varying means capable of changing the cross-sectional area of the freeboard portion above the fluidized bed. Layer classifier. 2. The fluidized bed classifier according to claim 1, further comprising heating means for heating the gas forming the fluidized bed to dry the processed material. 3. The container in which the fluidized bed is formed is divided into a plurality of chambers by a partition plate.
Or a fluidized bed classifier according to 2. 4. The fluidized bed classifier according to claim 3, further comprising distribution adjusting means for adjusting a flow rate distribution of the gas blown into the plurality of chambers to respectively form a fluidized bed. 5. The fluidized bed classifier according to claim 3, wherein the cross-sectional area varying means has a movable portion on at least a part of the partition plate. 6. The cross-sectional area varying means has a movable wall inside at least a part of a side wall surface forming a chamber in a container in which a fluidized bed is formed. The fluidized bed classifier according to claim 2. 7. The movable wall has a substantially rectangular shape,
The fluidized bed classifier according to claim 6, wherein the fluidized bed classifier is capable of swinging displacement about the lower side. 8. The fluidized bed classifier according to claim 6, further comprising a discharging unit configured to discharge the processed material accumulated in the space between the movable wall and the side wall surface outside the movable wall. 9. The container in which the fluidized bed is formed is provided with an input port for inputting a processed product on one side surface, and an exhaust port for discharging the classified processed product is provided on a side surface opposite to the one side surface. 9. The fluidized bed classifier according to claim 6, wherein the movable wall is provided on at least a part of the remaining side surface. 10. The container in which the fluidized bed is formed is provided with a charging port for charging a processed product on one side surface, and a discharging port for discharging the classified processed product on a side surface opposite to the one side surface. A movable wall is provided, and the movable wall is provided.
The fluidized bed classifier according to any one of 8 above. 11. A mass discharging means provided at the bottom of the dispersion plate near the charging port.
The fluidized bed classifier according to any one of 10.