JPH0256935B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a granulation and coating device for powder and granules.

Generally, granulation of powders and granules used for medicines such as tablets, fine granules, granules, capsules, foods such as thiokolate, powder metallurgy, catalysts, ferrites, ceramics, detergents, cosmetics, dyes, pigments, etc. Several types of mechanical equipment are used for coating as well. Some of them include, for example, pan- or drum-type rolling granulation/coating machines, agitation granulation machines with stirring blades, and furthermore, systems that fluidize and disperse powder and granules with air, and then apply a binding liquid or coating liquid. Spray to agglomerate or coat powder. There are so-called fluid granulation/coating machines.

By the way, for example, in granulation and coating in fields centered on pharmaceuticals and foods, it is necessary to produce particles with uniform particle size distribution, particles with good sphericity, fine powder,
It is required to produce grains with few aggregates or heavy grains, and there is also a requirement for a coating operation with no uneven coating, less destruction of grains, and less generation of adhering aggregates.

In response to these demands, conventional rolling granulation/coating machines use a cascade flow using gravity, so they do not apply strong local force to the grains, but due to poor mixing properties, granulation In this method, only non-uniform grains with a wide particle size distribution can be obtained, and in coating, agglomerates are likely to occur.

On the other hand, in a stirring granulator, particle destruction and granulation proceed at the same time due to stirring caused by local forces, so granulation tends to result in a broader particle size distribution, while coating tends to result in incomplete coatings. There are drawbacks.

In addition, although the fluidized granulation/coating machine has a mixing and dispersing action for powder and granules, it does not have a rolling action, so it has the disadvantage that it is difficult to produce heavy grains.

SUMMARY OF THE INVENTION An object of the present invention is to provide an apparatus capable of eliminating the drawbacks of the prior art and performing granulation and coating with good uniformity.

To achieve this object, the present invention provides a container having a substantially circular horizontal cross section with a substantially circular radius extending continuously from the axis of rotation to the outer periphery at one or more points on the axis of rotation provided at the center of a container having a substantially circular horizontal cross section. A rotary plate having a notch in the direction is provided along the bottom of the container, the area of the rotary plate covers almost the entire bottom surface of the container, and the front edge of the notch of the rotary plate in the rotation direction of the rotary plate is provided. is formed so as to be close to the bottom surface of the container, and gas introducing means is provided in the bottom region of the container for introducing gas into the container to cause the powder and granular material in the container to flow.

That is, granulation and coating essentially involve applying as uniform a shear to the powder bed as possible to give the particles a uniform mixing action without stagnation areas and a moderate rolling action. is necessary. In order to satisfy these conditions, instead of the stirring blades of the stirring granulator, a flat or dish-shaped rotary plate is installed along the bottom of the container to provide appropriate rolling motion to the powder layer. horizontally. In order to apply the centrifugal force necessary to generate a sufficient spiral flow effect on the powder layer, the rotating plate should have a size that covers at least 1/2 or more of the bottom surface of the container. Furthermore, in order to minimize the amount of powder that enters between the rotating plate and the bottom of the container, the rotating plate is preferably arranged along the bottom of the container so as to be as close as possible to the bottom of the container. Furthermore, in order to lift the powder particles that have entered the lower part of the rotary plate onto the rotary plate, it is preferable to cut out one or more parts of the rotary plate in the radial direction, and the front edge of the rotary plate in the rotational direction at the notch is Preferably it is closer to the bottom surface. With such a structure, as the rotary plate rotates, the powder and granular material under the rotary plate can be scooped up onto the rotary plate. In addition, by providing an air nozzle on the underside of the rotary plate to supply air between the rotary plate and the bottom of the container, the powder and granules under the rotary plate are blown up, and the front edge of the rotary plate in the rotation direction at the notch part is This makes it easier to scoop up the powder and granules under the rotary plate. As a result, there is no stagnation area for powder and granular material under the rotary plate at the bottom of the container. Furthermore, the bottom wall and/or side wall of the container is also provided with air nozzles,
Due to the centrifugal force generated by the rotation of the rotary plate, the powder particles that have reached the side wall of the container are floated along the container side wall while being flowed and dispersed by air, thereby promoting the swirling circulation mixing action of the powder particles.

In this way, the present inventors have improved the poor mixability associated with rolling granulation coating, prevented grain breakage due to localized excessive shearing forces seen in agitated granulators, and・Succeeded in giving particles a rolling action that is not available in coaching machines.

Furthermore, the granulation and coating device of the present invention has been gaining importance in the pharmaceutical and food industries in recent years, in addition to its inherent advantages in granulation and coating functions.
It has characteristics that cannot be overlooked from the standpoint of GMP (Good Manufacturing Practice).

That is, as devices that are seemingly similar to the present invention, there is a device in which a rotating disk is provided at the bottom of the fluidized bed to add rolling action to a fluidized bed granulation coating machine, and a device in which a rotating disk is provided on the fluidized bed air distribution plate. There is a device equipped with a plate, but in the former, powder and granules fall under the rotating disk,
The powder or granules may contaminate batches that are subsequently processed, reducing quality or making it difficult to clean thoroughly after a series of operations. On the other hand, in the latter case, in addition to this, there is a problem in that powder particles also enter between the rotating disk and the air dispersion plate. Therefore, both of the above conventional devices
This is problematic in terms of GMP.

On the other hand, unlike the conventional fluidized bed type device, the device of the present invention does not have an air dispersion plate or a gap where the granules can easily fall, so the granules are completely retained in the container and the powder is After discharging the granules from the container, complete cleaning is possible by simply lifting the rotary plate slightly during cleaning. Therefore, the apparatus of the present invention not only has excellent granulation and coating functions, but also is very good in terms of GMP.

In addition, as another conventional technique, a method has been proposed in which a rotating disk is provided along the bottom wall of the granulation tank, and particles are granulated by rolling and flowing on the rotating disk. However, with this conventional method, there is a problem in that powder and granules enter between the bottom wall surface of the granulation tank and the rotating disk, forming a stagnation zone.
This does not mean that there are no problems in terms of GMP.

In contrast, the device of the present invention has a radial notch formed in the rotary plate and introduces air between the bottom of the container and the rotary plate.
It is possible to prevent the powder from accumulating between the bottom of the container and the rotary plate, and it is very good not only in terms of granulation effect but also in terms of GMP.

Hereinafter, the present invention will be explained in detail according to embodiments shown in the drawings.

FIG. 1 is a schematic cross-sectional view showing one embodiment of the granulation and coating apparatus according to the present invention.

In this example, a container 1 for performing granulation and coating has a circular horizontal cross section, and a cover 2 is provided on the top, and the cover 2 has a powder supply pipe for supplying a fixed amount of raw material powder. 3. An exhaust pipe 4 for evacuating the inside of the container 1, a vacuum suction pipe 5 for bringing the inside of the container 1 into a desired vacuum state, and a spray nozzle 6 for supplying liquid for granulation and coating are provided.

On the other hand, at the center of the bottom of the container 1, a rotating shaft 7 that is rotatably driven by a drive source (not shown) is vertically protruded. A disc-shaped rotating plate 8 horizontally arranged along the bottom wall surface of the container 1 is fixed to the upper end of the rotating shaft 7 with bolts 9.
A truncated conical portion 8a at the center of the container 1 protrudes into the container 1,
Its outer peripheral side forms a flat plate portion 8b along the bottom surface of the container.

The rotary plate 8 rotates the powder 1 charged into the container 1.
0 is placed on the flat plate portion 8b of the rotary plate 8 and rotated, thereby imparting an appropriate rolling action to the granular material 10. In order to apply the centrifugal force necessary to generate a sufficient spiral flow action on the powder and granular material 10, this rotary plate 8 should cover more than 1/2 of the bottom surface of the container 1, preferably almost the entire surface. It is preferable to have an area.

It is desirable that the lower surface of the rotary plate 8 be as close to the bottom surface of the container 1 as possible to prevent the powder and granular material 10 from entering and accumulating between both surfaces as much as possible. The powder and granules that enter between the lower surface and the bottom surface of the container 1 are removed from the flat plate portion 8 of the rotary plate 8.
A notch 11 in the radial direction is formed at one location in the flat plate portion 8b of the rotary plate 8 in order to prevent the formation of a stagnation area of powder and granules below the rotary plate 8 by scooping the powder onto the rotary plate 8. This notch 11 is formed in a shape that becomes slightly wider as it goes from the inner side to the outer side in the radial direction when viewed in plan, and its cross-sectional shape is such that the front edge 11a in the rotational direction of the rotary plate 8 extends from the upper side to the lower side. The rotating plate 8 is cut diagonally toward the leading edge.
It is constructed so that the powder and granular material below can be easily scooped up onto the rotary plate 8.

In addition, in this embodiment, the powder and granules that have entered between the lower surface of the rotary plate 8 and the bottom surface of the container 1 are removed from the container 1.
Air is blown outwardly between the lower surface of the rotary plate 8 and the bottom surface of the container 1 through the rotary shaft 7 in order to blow it up in the circumferential direction and easily scoop it up onto the rotary plate 8 at the notch 11. A supply path 12 is provided. The air jet nozzle opening of this air supply path 12 may be formed in the radial direction of the rotating shaft 7, but if it is formed in the tangential direction of the rotating shaft 7, a better effect of blowing up and removing powder particles can be obtained, and the nozzle opening The number of objects is not limited to one. Further, the rotating shaft 7
A bearing 13 is provided around the top of the container at a position below the bottom wall of the container.

Furthermore, powder that has reached the side wall of the container 1 due to the centrifugal force caused by the rotation of the rotary plate 8 is located at the lower part of the side wall of the container 1 of this embodiment, that is, at a position corresponding to a position slightly above the flat plate portion 8b of the rotary plate 8. An air nozzle 14 is provided to float the granules 10 along the side wall while being fluidized and dispersed by the force of the air, and to promote the swirling circulation mixing action of the granules 10. The air nozzle 14 may be opened to introduce air in the radial direction of the container 1, but in order to better circulate and mix the powder and granular material 10, the air nozzle 14 may be opened in a tangential direction to the container 1. It is preferable to open the opening. The number of air nozzles 14 is not limited to one at all, and a plurality of air nozzles 14 may be provided, or may be provided on the bottom wall of the container 1.

Inside the side wall of the container 1 of this embodiment, a powder 1
A baffle plate 75 is provided to assist the mixing action of 0. However, this baffle plate 15 may be omitted. Further, a product discharge section 16 for taking out the granulated or coated product to the outside of the container 1 is formed at the lower side wall of the container 1, and is opened and closed by a valve 17. Furthermore, in this embodiment, the humidity, temperature, etc. in the powder 10 to be granulated or coated are sensed, and the amount of liquid supplied from the spray nozzle 6, the amount of hot air supplied from a hot air supply source (not shown), etc. A sensor 18 serves to control the container 1.
is installed inside.

Next, the operation of this embodiment will be explained.

First, a required amount of powder raw material for granulation and coating is introduced into the container 1 through the powder supply pipe 3 from a hopper (not shown). On the other hand, when the rotary shaft 7 and the rotary plate 8 are rotated by a drive source (not shown), the powder raw material in the container 1 is subjected to centrifugal force on the flat plate portion 8b of the rotary plate 8, as shown as powder 10 in FIG. As the rotating plate 8 rotates, the granular material 10 receives a uniform mixing action and a rolling action as the rotating plate 8 rotates.

On the other hand, since the lower surface of the rotary plate 8 and the bottom surface of the container 1 are close to each other and the flat plate part 8b of the rotary plate 8 is formed with a radial notch 11, powder particles that have entered the lower side of the rotary plate 8 The particles are scooped up onto the rotary plate 8 from the notch 11, and the accumulation of powder and granular materials below the rotary plate 8 is prevented.

In addition, since air is ejected between the lower surface of the rotating plate 8 and the bottom surface of the container 1 through the air supply path 12 provided on the rotating shaft 7, the powder and granules on the bottom surface of the container are blown up by this air. This makes it easier to scoop up the powder onto the rotary plate 8 through the notch 11, and the accumulation of powder and granules below the rotary plate 8 is more reliably prevented.

Furthermore, in this embodiment, since the air nozzle 14 is provided at the lower part of the side wall of the container 1, the powder 10 that has reached the container side wall due to the centrifugal force caused by the rotation of the rotary plate 8 is blown by air from the air nozzle 14. The particles are floated up while being fluidized and dispersed along the side wall of the container, and the swirling circulation mixing action of the powder and granules 10 is promoted.

Therefore, according to this example, the powder to be granulated and coated is subjected to not only a uniform fluid mixing action but also a moderate rolling action and further a spiral circulation mixing action. Because you will be coached,
It is possible to obtain powder with uniform particle size, and it is possible to make heavy particles without agglomerates, and it prevents powder destruction due to local excessive shearing force in conventional stirring granulators. It is also possible to prevent particles from accumulating.

Furthermore, since the granulation and coating apparatus of this embodiment does not have an air dispersion plate, the powder 10 is completely retained in the container 1, and when the container is cleaned after the powder 10 is discharged from the container 1. , complete cleaning can be carried out by simply lifting the rotary plate 8 slightly from the rotary shaft 7, which is extremely excellent from a GMP standpoint.

FIG. 4 is a partial sectional view showing another embodiment of the cutout portion of the rotating plate according to the present invention. In this embodiment, the notch 11 of the flat plate part 8b of the rotary plate 8 is such that the front edge 11b in the rotation direction of the rotary plate 8 is bent toward the bottom wall of the container 1, that is, downward, and its tip is very close to the bottom of the container. are doing. Therefore, in this case, as the rotating plate 8 rotates, the powder and granules on the bottom of the container are more easily and reliably scooped up by the curved front edge 11b in the rotational direction, and the powder and granules on the bottom surface of the container are scooped up more easily and reliably by the curved front edge 11b in the rotational direction,
It is returned to the top of b.

FIGS. 5 and 6 are plan views showing other embodiments of the rotating plate according to the present invention. That is, the fifth
In the illustrated embodiment, the notches 11 of the flat plate portion 8b of the rotating plate 8 are formed at two locations 180 degrees apart in the diametrical direction. In addition, in the embodiment shown in FIG.
A total of three are formed at 120 degrees from each other.
Note that the notch 11 is not limited to this,
For example, four or more cutouts 11 can be formed, and when a plurality of cutouts 11 are formed, the effect of scooping up the powder or granular material becomes greater than when only one cutout section 11 is formed.

FIG. 7 is a sectional view showing another embodiment of the granulation and coating apparatus according to the present invention. In this embodiment, the side wall portion of the container 1a is formed into a curved shape, and the diameter becomes smaller toward the upper end. In the case of such a container 1a, there is an advantage that the circulation mixing effect of the powder and granular material in the container becomes better. Furthermore, in this embodiment, the buttful plate that can be provided inside the side wall of the container is omitted;
A full board may also be provided.

FIG. 8 is a sectional view showing still another embodiment of the present invention. In this embodiment, in addition to the side wall portion of the container 1a, the bottom wall portion is also curved, and the flat plate portion of the rotary plate 8 is also formed as a dish-shaped curved plate portion 8c that curves along the curved bottom wall portion. ing. In this embodiment as well, good rolling action and circulation mixing action can be obtained.

Note that the present invention is not limited to the above embodiments, and various other modifications are possible.

As explained above, according to the present invention, granules with uniform particle size can be granulated and coated without causing grain breakage due to locally excessive shearing force, and without generating aggregates. It is possible to produce heavy grains, prevent granules from accumulating between the bottom of the container and the rotary plate, and achieve excellent effects in terms of GMP. In particular, in the present invention, the notch in the rotary plate extends continuously from the rotating shaft to the outer peripheral edge, and the front edge of the notch in the rotational direction of the rotary plate is formed close to the bottom surface of the container. Together with the action of air introduced between the rotary plate and the bottom of the container, the powder and granules that have fallen below the rotary plate are reliably scooped up from above the bottom of the container onto the rotary plate.

Further, in the present invention, since the area of the rotating plate covers almost the entire bottom surface of the container, a uniform and high-quality granulated coating product can be obtained by the centrifugal rolling flow action of the powder particles on the rotating plate.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing an embodiment of the granulation and coating apparatus according to the present invention, Fig. 2 is a half plan view of a rotating plate, Fig. 3 is a sectional view taken along the line - - of Fig. 2, and Fig. 4 is a rotating plate. FIGS. 5 and 6 are plan views showing other embodiments of the rotary plate, and FIG. 7 is a partial sectional view showing other embodiments of the cutout portion of the plate, and FIG. FIG. 8 is a sectional view showing still another embodiment of the apparatus of the present invention. 1, 1a... Container, 2... Cover, 3... Powder supply pipe, 6... Spray nozzle, 7... Rotating shaft,
8... Rotating plate, 8a... truncated conical part, 8b... flat plate part, 8c... curved plate part, 10... granular material, 11
...Notch portion, 11a, 11b...Rotational direction front edge portion, 12...Air supply path, 14...Air nozzle,
16...shoot, 17...valve.

Claims (1)

[Claims] 1. A rotating plate having a substantially radial notch extending continuously from the rotating shaft to the outer peripheral edge at one or more locations on the rotating shaft provided at the center of a container having a substantially circular horizontal cross section, The rotary plate is provided along the bottom surface of the container, the area of the rotary plate covers almost the entire bottom surface of the container, and the front edge of the notch of the rotary plate in the rotating direction of the rotary plate is formed close to the bottom surface of the container, The granulation and coating apparatus further comprises a gas introduction means provided in the bottom region of the container for introducing gas into the container for causing the powder and granules in the container to flow.