JPS6146387Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an apparatus in which perforated plates are arranged in multiple stages and powder and granular material is continuously dried while falling from the upper perforated plate to the lower perforated plate one after another.

A large number of radial baffles are provided on the disk, and the disk is rotated in a horizontal plane (called gyroscopic motion).
There is an apparatus for supplying raw materials onto a disk and moving it in a circular direction, and a granulating apparatus as an example thereof is known as JP-A No. 28779 of 1977. This Batsuful has a mountain-shaped (triangular) cross section, and the slope of one side of the mountain is different from the slope of the other side. For example, the slope in the direction of rotation of the gyroscope is 30 degrees, and the other side is 60 degrees. There is.

The powder and granules supplied onto the disk move in a circular motion on the disk according to the circular motion of the disk, and due to the inertia at that time, it climbs up a slope with a small inclination and climbs up a slope with a large slope. As a result, the powder and granules end up moving in a circular direction on the disc while passing over the buttful. As a result, granulation is performed without the powder particles sticking to the disk.

A drying device utilizing the movement of powder particles in the above-mentioned granulator is disclosed in Japanese Patent Application No. 54-123522 (Patent Publication No. 56-123522).
This has been proposed by the present applicant as a prior art device under the name of US Pat. No. 46972.

In this method, annular perforated plates are arranged in multiple stages within a rotating cylindrical case, and the material to be dried is dried while being moved from the top stage to the bottom stage. In this device, material is dropped sequentially from the upper stage to the next stage, and for this purpose, radial rectangular drop openings are formed in each perforated plate except the lowest stage, and the lower surface of the perforated plate is near the perforated plate of the next stage. There is a drop tube that hangs down to the top. Therefore, the drop openings in the next stage and below are provided in a staggered manner from the drop openings in the upper stage.

Drying gas is supplied below the bottom perforated plate,
The material flows upward sequentially from there and passes through each perforated plate, drying the material moving on each perforated plate.

The aforementioned falling opening extends radially from an inner position close to the central annular opening between the two buttfuls to near the outer periphery, and has a rectangular shape.
The inner width is smaller than the outer width, forming a part of a fan.

The material supplied to the top stage moves in a circular direction on the perforated plate, and when it reaches the drop opening, it descends inside the drop tube and falls onto the perforated plate in the lower stage, where it moves in the circular direction and is sequentially While falling, it is dried while reaching the perforated plate at the lowest stage, and then taken out to the outside.

By the way, when we examined the product after drying, it was found that the degree of dryness of large particles and small particles was different, with the degree of dryness of large particles being lower, and that the degree of dryness of the product tended to be uneven.

When we observed the movement of the material while conducting experiments, we found that when the material moves in a circular direction on the perforated plate while passing over the buttful due to the gyroscope movement, large particles tend to cross over the butthole while facing toward the center. In the end, we discovered that the large particles were moving in a circular direction near the center. Therefore, on the perforated plate, the distance from the drop position to the drop opening is shorter for large particles than for small particles, and the residence time of large particles is correspondingly shorter.

Although large particles themselves require time to dry, their residence time is shorter than that of small particles, so the difference in dryness between large particles and small particles becomes large.

Therefore, in order to eliminate undried large particles in the product, there was no choice but to select a drying time that would allow the large particles to be sufficiently dried. As a result, the drying time becomes longer and the amount of heat required for drying increases, which is uneconomical. In addition, small particles become overdried,
In some cases, quality was compromised.

The present invention improves the above-mentioned drawbacks by making the residence time of large particles on the perforated plate longer than that of small particles so that the dryness of the product becomes uniform without causing a large difference. It is.

Therefore, in the present invention, in the drying device like the previous one, the drop opening formed in the perforated plate is rectangular, with its long sides extending in the radial direction, and the inside of the opening is It is further away from the center circular hole of the hole plate. As a result, the perforated plate portion remains as it is between the central circular hole and the inside of the drop opening, serving as a material transfer portion.

Furthermore, in order to prevent large particles of material approaching the drop opening that pass through the inside of the drop opening from falling into the drop opening, a perforated plate with one end located inside the drop opening and a partition wall concentrically extending in an arc shape from the drop opening is used. is placed above.

Therefore, while the material supplied onto the perforated plate moves in a circular direction and reaches the falling opening, large particles are separated near the center and small particles are separated to the outside.
Most of the small particles fall from the drop opening, and most of the large particles move on the perforated plate part inside the fall opening and try to continue their second round of movement. A new material is supplied on top of that, and as a result of mixing there, the large particles of the new material, which have a higher specific gravity than the large particles that have already been dried and become lighter, move in a circular direction while moving toward the center, and Most of the large particles will move on the outside and fall from the drop opening to the next stage, resulting in longer residence times and correspondingly longer drying times.

In addition, if the material, which is divided into large particles near the center and small particles at the outer periphery, reaches the tip of the arc-shaped partition before reaching the falling opening, it will be divided into two parts, inside and outside.
The one closest to the center continues to move past the inside of the drop opening, while the one on the outside reaches the drop opening and falls to the next stage.

Embodiments of the present invention will be described with reference to the drawings.

In the drawing, 1 is a cylindrical case, and inside thereof, five annular perforated plates 2, 3, 4, 5, and 6 are arranged at equal intervals in multiple stages. It is attached to the periphery. A material supply port 7 and a hot air discharge port 8 are provided on the top wall of the cylindrical case 1 near the outer periphery. An opening is provided in the center of the top wall, and the opening and the annular perforated plates 2, 3, 4, 5,
Hot air supply pipe 9 inserted through the center opening of 6 and fixed.
The lower end of the cylindrical case 1 is located below the bottom perforated plate 6.
It opens toward the bottom wall. A material discharge port 10 is provided on the peripheral wall of the cylindrical case 1, which is located above the upper surface of the lowest perforated plate 6, and a material discharge pipe 11 is connected to the material discharge port 10.

Although not shown on the bottom surface of the cylindrical case 1,
A gyroscope drive device is provided, which is the same as that in the granulating device of JP-A No. 54-28779, in which the bottom wall of the case 1 is rotatably supported by a plurality of vertical eccentric shafts. A plurality of interlocking gears are fixed to the lower end of the shaft, and due to the interlocking of the gears, the cylindrical case 1 revolves around a constant radius in a horizontal plane without rotating itself.

As shown in FIG. 2, the uppermost perforated plate 2 has an annular shape in which a large number of small holes (not shown) are formed, and a circular opening is formed in the center. On the perforated plate 2, a large number of buttfuls 12 are provided at equal intervals extending radially from the central circular opening to the outer periphery, and this has a triangular cross section, with two hypotenuses protruding in a chevron shape. The inclination to the disk is a small angle of about 30°, and the other hypotenuse is a large angle of about 60°. (In the figure, the width of the wide Batsuful 12 has a smaller inclination, and the narrower width has a larger inclination.) Therefore, due to the gyroscope movement, the powder and granules move in the direction of the arrow.

A drop opening 13 is provided at one location on the perforated plate 2, and this is in the shape of a part of a fan formed in the flat plate part between the buttholes 12, and its outer periphery is near the outer periphery of the perforated plate 2. The inner circumference is a perforated plate 2.
The central circle is away from the aperture. Therefore, a flat plate portion is left between the inner periphery of the drop opening 13 and the circular opening, and the length of this flat plate portion in the radial direction is approximately 1/1/2 of the radius of the perforated plate 2 in the illustrated example. 4, but its size is determined by the amount of large particles in the powder. One side of the drop opening 13 is in contact with the buttful 12, and a weir plate 14 is provided in contact with the other side (front in the moving direction of the powder and granular material).

The arcuate partition wall 18 has one end located on the inner periphery of the drop opening 16 on the perforated plate 2, and the other end extends rearward as part of a concentric circle with respect to the traveling direction of the powder and granular material. The length of the arc is such that it spans four Batsuful 12s, and the Batsuful 12 is on the lower side.
A notch corresponding to the perforated plate 2 is formed, and the entire lower side is covered with the perforated plate 2.
fixed on top. The upper end of a drop tube 15 is welded to the lower surface of the drop opening 13, as shown in FIG. The cross section of the drop tube 15 is the same as the drop opening 13, and the drop tube 15 hangs downward, and its lower end has a certain distance from the top surface of the perforated plate 3 in the next stage in FIG. ing. This gap is such that it is always blocked by powder and granules during the drying operation, and as a result, hot air is prevented from blowing through. Therefore, the size of the above-mentioned interval is selected depending on the fluidity of the powder and the rotational speed of the gyroscope motion.

Perforated plates 3, 4, 5 below the second stage in Fig. 1
differs only in the position of the drop opening.

As shown in FIG.
Similarly, a buttful 12 is provided on the perforated disc. The falling opening 16 is located at the rear of the falling opening 13 of the perforated plate 2 of the first stage in the moving direction of the powder and granular material. Similarly to the perforated plate 2, the weir plate 14
is provided on one side of the drop opening 16, and the buttful next to the weir plate 14 is a large buttful 17 which is higher than the other buttfuls 12 and whose top extends above the lower end of the drop tube 15. Also, a partition wall 18 is provided like the first stage perforated plate 2. The hanging direction of the falling tube 15 of the perforated plate 2 is between the weir plate 14 of the perforated plate 3 of the second stage and the large baffle 17. Similar to the perforated plate 2, a drop tube 15 is fixedly suspended from the lower surface of the drop opening 16 of the perforated plate 3.

The third and fourth stage perforated plates 4 and 5 are similar to the perforated plate 3, and the positions of the drop opening 16 and the large baffle 17 are shifted rearward in the flow direction of the powder and granular material.

The lowermost perforated plate 6 does not have the drop opening and drop tube of the upper perforated plate, and has a full 12
is provided, and has a large baffle 17 and a weir plate 14 corresponding to the falling tube 15 of the upper perforated plate 5, but the weir plate 14 serves as a discharge guide plate for powder and granules, and its outer end is used as a material discharge guide plate. It is in contact with one side of the discharge port 10.

To carry out the drying work, the cylindrical case 1 is driven by a gyroscope drive device, the powder to be dried is continuously supplied from the material supply port 7, and the upper end of the hot air supply pipe 9 is connected to a hot air source through a flexible pipe. Hot air is supplied into the cylindrical case 1 while communicating with the cylindrical case 1.

After the hot air blows out from the bottom surface of the lowest perforated plate 6, it turns around and ascends from the small holes in the perforated plate 6 sequentially through the small holes in the perforated plates 5, 4, 3, and 2 above it, The hot air is discharged from the hot air outlet 8 to the outside. The supplied powder falls onto the top perforated plate 2, and the hot air rising from below prevents the fine powder from falling from the small holes.In this state, the perforated plate 2 By rotating, it moves in a circular direction (indicated by an arrow) while repeating over the small slope of the buttful 12 and falling down the large slope, during which time it is dried by the passage of hot air from below. During this time, most of the large particles in the powder gather near the center of the perforated plate 2, and when they reach the end of the arc partition wall 18, they are divided into two, large particles on the inside and other particles on the outside. It continues to move along the inside and outside of the bulkhead. Partition wall 18
As a result of movement, the powder on the outside reaches the drop opening 13 as shown by the arrow, and then falls from the drop tube 15 onto the perforated plate 3 at the next stage. At this time, the powder particles trying to pass through the falling opening 13 collide with the weir plate 14.

On the other hand, the large particles inside the partition wall 18 continue to move in a circular direction, pass through the inside of the drop opening 13, make one revolution, and merge with the continuously supplied powder and granules. While they merge and move in a circular direction, the large particles that have already rotated once are mixed with the newly supplied powder, and the large particles that have already been dried and become lighter are pushed outward by the new large particles. , and reaches the drop opening 13 through the outside of the partition wall 18 during the second rotation. Therefore, most of the large particles make two turns on the first stage perforated plate 2, and some make three or more turns, resulting in a longer residence time.

The powder and granular material falling from the falling tube 15 passes through the perforated plate 3 of the next stage.
The material falls between the weir plate 14 and the large buttful 17, accumulates between them, seals the space between the lower end of the drop tube 15 and the perforated plate 3 (material seal), and maintains that state. The lower layer of the deposited powder and granules sequentially move in a circular direction over the small inclined surface of the large buffle 17. The powder and granules then move in a circular direction passing over a large number of baffles 12 one after another, and during this time the same process as on the perforated plate 2 of the first stage is repeated, and the powder that has reached the falling opening 16 of the perforated plate 3 The particles fall from the falling tube 15 to the perforated plate 4 at the next stage, and are kept in a piled and blocked state at the falling point. Thereafter, the perforated plates 4 and 5 are moved in a circular direction and dropped while repeating the same condition.
On the perforated plate 6 at the lowest stage, the lower layer of the deposited powder moves sequentially in a circular direction, and at the end thereof is guided to the material discharge port 10 by the weir plate 14, and is guided to the material discharge pipe 11.
After that, it is discharged while maintaining airtightness using a rotary valve etc.

As a result of the above, the residence time of large particles becomes longer until they are discharged, and the larger particles are dried accordingly.

On the other hand, as mentioned above, hot air is supplied from the lower end of the hot air supply pipe 9, but as mentioned above, each of the perforated plates 2, 3,
4, 5, and 6 are covered with a powder layer moving in a circular direction, and the space between each perforated plate is blocked by material accumulation at the lower end of the drop tube, so hot air does not blow through and reaches the lower perforated plate. It passes through the small holes of 6 and rises while contacting the powder and granules, and then passes through the perforated plates 5, 4, 3, 2.
The hot air rises in this order from below to above while coming into contact with the powder and granules, and is finally discharged to the outside from the hot air outlet 8.

As described above, according to the present invention, there is a perforated plate section inward from the inside of the falling opening in the drying device as described above, and large particles are reduced to small particles by moving over the plate twice or more. Since the residence time is longer than that of particles, the dryness of large particles increases accordingly, and due to the drying time required to dry small particles, the dryness of large particles and small particles become similar, and the dryness of the product increases. It becomes almost uniform.

In addition, an arc-shaped partition wall extends from one end of the falling opening, and the material is separated into large particles and small particles inside and outside, and the large particles move for the second time, so almost the entire large particle goes around twice. The movement of the eyes is ensured, and the occurrence of insufficiently dried large particles is extremely small.

As a result of the above, a substantially uniform product can be sufficiently obtained with the time and heat required for drying small particles.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention.
The figure is a diagrammatic cross-section with some parts omitted, FIG. 2 is a plan view of the uppermost perforated plate, and FIG. 3 is a partial side (cross-sectional) view. 1 is a cylindrical casing, 2, 3, 4, 5, 6 are perforated plates, 7 is a material supply port, 8 is a hot air discharge port, 9 is a hot air supply pipe, 10 is a material discharge port, 11 is a material discharge pipe, 12 is Batsuful, 13 and 16 are falling openings, 1
4 is a weir plate, 15 is a drop tube, 17 is a large baffle, and 18 is an arcuate bulkhead.

Claims (1)

[Scope of utility model registration request] Perforated plates with a large number of buttfuls extending radially from a central circular hole are arranged in multiple stages within a cylindrical casing equipped with a revolution drive device. In a continuous drying device with a drop cylinder hanging downward, the drop opening is rectangular and extends in the radial direction, and the inside of the opening is away from the central circular hole of the perforated plate, and the part inward from the inside becomes the perforated plate part. , a continuous drying device using a multi-stage perforated plate, in which one end is located inside the drop opening, and a partition wall extending in a concentric arc shape from the perforated plate is provided on the perforated plate.