JPH07102313B2 - Fluidized bed granulation method and apparatus - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a fluidized bed granulation technique, and more particularly to a gas to be introduced into a processing container and a tumbling flow action by a rotor rotating in the processing container to be treated. The present invention relates to a technology for granulating a product.

[Conventional technology]

As the fluidized bed granulator, for example, as shown in FIG. 2, an intake filter 1, a steam heater 2, a wind chamber 3, a pushing device 4, a carriage 5, a wire net 6, a raw material container 7, a spray chamber 8, and a spray nozzle 9. A bag filter 10, a scrubbing device 11, a scrubbing cylinder 12, a ventilation stop damper 13 (exhaust damper), and a ventilation stop cylinder 14 can be considered. However, in this apparatus, since the powder and granules in the raw material container 7 have a fluidizing action only by the gas from the air chamber 3, it is difficult to obtain a heavy granule.

Therefore, in order to eliminate such a problem, conventionally, a method of rotating a fluidized bed to obtain a heavy and spherical granulated product is widely known and is also used as an apparatus. However, in these devices, when the damper is fully closed and ventilation is temporarily interrupted in order to facilitate dust removal during dust removal from the bag filter, between the inner wall of the raw material container and the outer periphery of the rotor. In order to prevent the raw material from falling into the lower part of the rotor from the annular gap formed in, the annular gap can be closed by, for example, providing a seal on the outer periphery of the rotor or providing a vertically movable seal ring below the gap. It is configured.

[Problems to be solved by the invention]

However, in this structure, since the raw material container or the seal ring is in contact with the rotor or the seal, it is necessary to temporarily stop the rotation of the rotor. For this reason, the effect of rolling operation by the rotor is halved.

In addition, in order to prevent the raw material from falling below the rotor from the gap, separate the pulse jet sweeping device or bag filter that does not require temporary interruption of ventilation even when dusting off, and separate them in two chambers. A device equipped with a mechanism for performing is also conceivable. Since this method always ventilates, it is not necessary to completely close the gap. Therefore, although the rotation of the rotor is not interrupted, the raw material on the rotor is always in a fluid state, which makes it difficult to receive the rolling operation of the rotor.

Therefore, in the case of expecting a large amount of rolling motion by the rotor, there is also a method in which the rotor is not provided with a ventilation wire mesh and the rotor is used as a blind so that only the gap is ventilated and the raw material does not flow but only rolls on the rotor. It is conceivable that the amount of hot air is small and the drying speed is slow, so it takes a long time to spray a predetermined amount of binder, a nodule occurs due to excessive raw material water in the middle, and a separate dryer is required for finish drying. The inventor has found that there are drawbacks.

In view of the above-mentioned problems, an object of the present invention is to provide a fluidized bed granulation technique capable of obtaining a heavy and spherical granulated product.

Another object of the present invention is to provide a fluidized bed granulation technique capable of shortening the granulation time.

Still another object of the present invention is to provide a fluidized bed granulating apparatus capable of obtaining a heavy and spherical granulated material by simply replacing a part of an existing fluidized bed granulating apparatus. .

[Means for solving problems]

In order to solve the above-mentioned problems, the fluidized granulation method of the present invention, while continuing the rotation of the rotor, the spray supply is stopped, and the exhaust damper is fully closed to stop the ventilation of the bag filter. After the cleaning operation of No. 1 is performed, the exhaust damper is fully opened to restart ventilation, and the supply of the spray is restarted.

Further, the fluidized bed granulating apparatus of the present invention includes a raw material container that is attachable to and detachable from a lower portion of a processing container, a rotor that rotates within the raw material container, a rotor driving unit that rotationally drives the rotor, and the raw material container. Gas introducing means for introducing gas into the raw material container through an annular gap between the inner wall surface and the outer peripheral surface of the rotor, a breathable leak preventer provided below the annular gap, and the ventilation. And a labyrinth means for partitioning a space between the sex leak prevention means and the rotor, and a product takeout means for taking out the product in the raw material container to the outside.

[Action]

According to the method of the present invention described above, operations such as removing the deposits on the filter can be performed in a short time, the entire granulation time can be shortened, and moreover, by continuing the rotation of the rotor It is possible to obtain a spherical granulated product.

Further, according to the apparatus of the present invention described above, a heavy and spherical granulated material can be obtained by merely replacing the existing fluidized bed granulating apparatus with a part thereof.

〔Example〕

FIG. 1 is an enlarged partial sectional view of a main part of a fluidized bed granulator according to the present invention.

The fluidized bed granulating apparatus of this embodiment has a structure that is interchangeable with the lower part A from the raw material container 7 in the apparatus shown in FIG. 2, for example. Therefore, the portion B above the raw material container 7 in the apparatus shown in FIG. 2, that is, the main body of the fluidized bed granulating apparatus and the like can be used in common in the apparatus of this embodiment, and therefore, in this embodiment, common reference numerals are used for them. , And detailed description of each is omitted.

As shown in FIG. 1, the raw material container 7 of this embodiment has a conical lower part and a cylindrical upper part. The raw material container 7 has a granular raw material in which it is centrifugally tumbled to flow. A rotor 21 for granulating is provided. A rotor is provided on the side surface of the raw material container 7.
A discharge port 36 is provided at the height at which 21 is installed. The raw material container 7, together with the rotor 21 and the like, can be attached to and detached from the lower portion of the spray chamber 8 that constitutes the main body of the fluidized bed granulator. At the lower part of the raw material container 7, there is a speed reducer chamber 31 supported by ribs 33 from the peripheral wall, and a worm speed reducer 32 is installed therein. The rotor 21 and the center cone 35 are attached to a vertical output shaft of the speed reducer 32 via a boss 34.

A ventilation wire mesh 22 is provided in a ring shape on a part of the rotor 21. A gap between the inner wall of the raw material container 7 and the outer circumference of the rotor 21
At the lower part of 41, for example, a rotor lower ring 24 having a circumferential ventilation opening formed in a part thereof and a lower wire net 25 (air permeable leak-preventing means) for preventing raw material falling below are provided. 25 forms a labyrinth structure with the labyrinth member 23 that partitions the space between the rotor 21 and the rotor 21. That is, a standing wall portion 24a bent so as to extend upward is formed at the inner peripheral end of the rotor lower ring 24, and the labyrinth member 23 has a lower surface of the rotor 21 so as to form a labyrinth structure with the standing wall portion 24a. It is extended downwards in a ring shape.

The rotor 21 is rotationally driven by an electric motor 26. The rotor driving force of the electric motor 26 is transmitted from the output shaft 26a of the electric motor 26 to the speed reducer 32 via the universal joint 27, the spline joint 28, the universal joint 27a, the transmission shaft 29, and the universal joint 30. Spring S
Is attached to prevent the universal joint 27a and the insertion portion of the transmission shaft 29 from coming off. 28a is a bearing that rotatably supports the transmission shaft 29.

Next, the fluidized bed granulation method according to this embodiment will be described.

First of all, when the raw material is charged, the joint portion of the universal joint 27a and the transmission shaft 29 is removed, the push-up device 4 is lowered as usual, and the raw material container 7 is placed on the carriage 5 and removed from the main body. In this state, since the upper part of the raw material container 7 is open, the raw material is charged from the upper part of the raw material container 7. The raw material container 7 in which the raw material is charged is moved to a predetermined position of the main body by the trolley 5, and is set on the main body by raising the lifting device 4, and the universal joint 27a and the transmission shaft 29 are connected. During this time, the raw material falls through the gap 41 onto the lower wire net 25, but since it has the labyrinth member 23, it does not fall from this. When the ventilation is started after the setting of the raw material container 7 is completed, the raw material on the lower wire net 25 is blown up onto the rotor 21 through the gap 41 by the hot air.

After that, the rotation of the rotor 21 is started, and otherwise the same operation is performed. During operation, in order to easily remove the dust adhering to the bag filter 10, the damper 13 is normally closed for about 5 seconds every 60 to 120 seconds to ventilate the air, in other words, the raw material container 7
The raw material on the rotor 21 stops flowing in order to stop the discharge of gas from the container and the supply of gas to the raw material container 7, but the rotor 21 continues to rotate, so that the raw material is largely subjected to rolling operation from the rotor 21. . At this time, a part of the raw material falls from the gap 41 onto the lower wire net 25, but when the ventilation is restarted, the rotor is restarted.
21 is blown up.

These operations are repeated for a certain period of time, after finishing drying, the outlet
Open 36 and discharge the raw material. Since air is ventilated even when discharged, almost all of the granulated material that has been dropped on the lower wire net 25 is discharged.

According to the present example, the bulk specific gravity of the granules consisting of particles in the range of 32 to 80 mesh is about 20% of the granules by the conventional fluidized bed granulator under the same conditions, and the bag filter two chambers having the rotor. Approximately 10 of continuous ventilation system in a separate fluidized bed granulator
It has been confirmed to increase by%.

In addition, according to the present example, as compared to the conventional method, even if the water content of the raw material during the granulation step is increased, the generation of nodule is less, so by increasing the water content in the operable range It is possible to obtain spherical particles.
At the same time, by controlling the rotation speed of the rotor 21, the ventilation interruption interval, and the ventilation interruption time, it is possible to obtain a granulated product of any desired degree of heavyness.

According to the experiments conducted by the present inventor, although the granulation of the granulated product during finishing drying is greater than that of the other methods, it is also confirmed that it can be prevented by lowering the rotation of the rotor 21 during finishing drying.

On the other hand, according to the present embodiment, it is clear that the durability of the device is good as compared with the method of repeating the stop and start of the rotor 21 in a short time, and the step at the time of dust removal of the bag filter 10 is the conventional method. Spray stop-rotor 21 stop-descent-damper 13 fully closed-discharging-damper 13 fully open-rotor 21 ascend-start-spray start, in this embodiment, spray stop-damper 13 fully closed-discharging-damper
13 Fully open-Begin spraying, shortening spray stop time, leading to shortening of total granulation time.

Further, in this embodiment, the discharge port 36 is communicated with the sealed container 37, and the inside of the sealed container 37 is set to the same negative pressure as the inside of the raw material container 7.
Due to the rotation, the combined with the ventilation from below the raw material container 7, it is possible to take out extremely easily and surely.

The present invention is not limited to the above embodiment,
For example, it can be widely applied to the case of removing the deposit on the bag filter by the pulse jet.

〔The invention's effect〕

(1). A fluidized bed granulation method in which a gas is supplied from a lower portion of a raw material container into a raw material container, and an object to be processed is tumbled and fluidized on a rotor rotating in the raw material container to perform granulation. While continuing the rotation of the, while the spray supply is stopped, and the exhaust damper is fully closed to stop ventilation, the bag filter is wiped off, and then the exhaust damper is fully opened to ventilate the air. By restarting and restarting the supply of the spray, the rotor is continuously rotating even when an operation such as removing the adhering material from the filter is performed. It is continuously tumbled and flowed above, and a heavy and spherical granulated product can be obtained by the rolling motion of the rotor.

(2). According to the above (1), the spray stop time can be shortened, and the operation of removing the deposits on the filter can be performed in a short time, and the entire granulation time can be shortened.

(3). A main body of a fluidized bed granulating apparatus having a spraying means and an exhaust damper, a raw material container which is attachable to and detachable from a lower portion of the main body, a rotor which rotates in the raw material container, and a rotor driving means which rotationally drives the rotor, Gas introducing means for introducing gas into the raw material container through an annular gap between the inner wall surface of the raw material container and the outer peripheral surface of the rotor, and a gas permeable leak preventing means provided below the annular gap. When,
The labyrinth means for partitioning the space between the breathable leak-proof means and the rotor, and the product take-out means for taking out the product in the raw material container to the outside, thereby the raw material container and the rotor of the existing fluidized granulator. A heavy and spherical granulated product can be obtained simply by exchanging etc.

[Brief description of drawings]

FIG. 1 is an enlarged cross-sectional view of a main part of a fluidized bed granulator which is an embodiment of the present invention, and FIG. 2 is a schematic explanatory view of a conventional fluidized bed granulator. 1 ... Intake filter, 2 ... Steam heater, 3 ... Wind chamber, 4 ... Pushing up device, 5 ... Truck, 6 ... Wire mesh, 7 ... Raw material container, 8 ... Spraying chamber, 9 ... Spray Nozzle, 10 …… Bag filter, 11 …… Shaping device, 12 …… Shaping cylinder, 13 …… Ventilation stop damper, 14 …… Ventilation stopping cylinder, 21 …… Rotor, 22 …… Ventilation wire mesh, 23 …… Labyrinth member, 24 …… Rotor lower ring, 24a …… Standing wall, 25 …… Lower wire mesh, 26 …… Electric motor, 26a …… Output shaft, 27 …… Universal joint, 27a …… Universal joint, 28… … Spline joint, 28a …… Bearing, 29 …… Transmission shaft, 30 …… Universal joint, 31 …… Reducer room, 32 …… Reducer, 33 …… Rib, 34 …… Boss, 35 …… Center cone, 36 …… outlet, 37 …… sealed container, 41 …… gap.

Claims (4)

[Claims] 1. A fluidized bed granulation method in which a gas is supplied into the raw material container from the lower part of the raw material container, and an object to be treated is tumbled and fluidized on a rotor rotating in the raw material container for granulation. Therefore, while continuing the rotation of the rotor, after stopping the supply of spray, and after performing a blow-off operation of the bag filter in a state where the exhaust damper is fully closed and ventilation is stopped,
A fluidized bed granulation method, characterized in that the exhaust damper is fully opened to resume ventilation, and supply of the spray is resumed. 2. A main body of a fluidized bed granulating apparatus having a spraying means and an exhaust damper, a raw material container which can be attached to and detached from a lower portion of the main body, a rotor which rotates in the raw material container, and a rotational drive of the rotor. A rotor driving means, and gas introducing means for introducing gas into the raw material container through an annular gap between the inner wall surface of the raw material container and the outer peripheral surface of the rotor,
Breathable leakproof means provided below the annular gap, labyrinth means for partitioning the space between the breathable leakproof means and the rotor, and product takeout means for taking out the product in the raw material container to the outside. And a fluidized bed granulator. 3. The fluidized bed granulator according to claim 2, wherein the rotor is attachable to and detachable from the main body of the fluidized bed granulator together with the raw material container. 4. The fluidized bed structure according to claim 2, wherein the product take-out means is communicated with a sealed take-out container that is kept under substantially the same negative pressure as the processing chamber of the main body. Grain equipment.