JPH0616826B2 - Granulation coating equipment - Google Patents

Description

TECHNICAL FIELD The present invention relates to a granulation coating apparatus for coating a liquid agent on a powder surface.

Prior art U.S. Pat.No. 4,027,624 discloses that solid particles to be granulated are stored in a packed bed, and heated air is sent from the bottom of the packed bed to reduce the resistance of the fixed particles as a fluidized bed to form a particle group. The particles are blown up, and the coating liquid is sprayed with compressed air in a spray form on the blown-up particle group to coat the particles, and at that time, the solid particles scattered by the spraying pressure are aired without flowing out to the outside by a filter. A technique is disclosed in which only the only one is discharged. The granulating coating device of this kind is also initially provided on the ceiling of a cylindrical container with a sieve-shaped container whose bottom is covered with a wire mesh, and the container is filled with a required amount of the coating liquid. The solid particles are naturally dropped through the wire mesh, while the solid particles stored in the cylindrical container are rotated in the vicinity of the bottom of the cylinder with a stirring blade that rotates about an axis perpendicular to the bottom as a central axis, and at the bottom of the stirring blade. The powder was flow-shear mixed with a fixed pin fixed with a gap to convectively mix.

Problems to be solved U.S. Pat.No. 4,027,624 has a technique in which solid particles have a certain temperature and also serves to dry the solid particles, and hot powder is stored in the packed bed. Since the coating liquid is sprayed with compressed air onto the particles that have formed a fluidized bed by spraying, the particles of solid particles scatter in the container, and a filter group is arranged in the upper layer, and this filter group is used. Even if air is sucked in and exhausted,
The coating film for the particles is not always uniform, and the solid particles are aggregated to widen the size of the particles, that is, the particle size distribution, and the solid particles are effectively coated because of the scattering of the powder. The proportion of solid particles to be coated is reduced accordingly, and when the ratio of the solid particles to be completely coated and the coating liquid is 100%, it reaches 103% or more, and the yield ratio is low. In the case of an expensive coating liquid, there is a drawback that the cost increases correspondingly and a large loss is generated in terms of profit. Also, in the latter example, the dropping amount of the coating liquid is affected by the viscosity of the liquid and uniform dripping becomes impossible.Furthermore, when the amount of liquid in the sieve container decreases, the reduced pressure on the wire mesh decreases and the viscosity increases. It becomes impossible to flow down against, and the droplets condense into large particles and fall into the fixed powder, so that large variations in the coating particles occur, and good quality granulated coating cannot be performed. Furthermore,
In the conventional apparatus, as a result, the efficiency of the granulation coating is poor, so that the granulation time becomes long, not only the quality but also the production time becomes long, and the granulation cost is insufficient in both quality and man-hours. there were.

Means for solving the problem The above-mentioned conventional granulating coating apparatus uses a fluidized bed,
Although it utilizes natural dropping, focusing on the fact that the mixing condition of the coating liquid is a problem in the present invention, a plurality of filament-like continuous particles in which the coating liquid is continuous with the solid particles are mixed around the blade upper part. By individually arranging and spraying at a substantially uniform ratio with respect to the solid powder, it is possible to perform granulation coating as soon as possible, with uniform and good yield.

Example FIG. 1 is a diagram showing a schematic view of a granulation coating apparatus according to the present invention, in which 1 is a cylindrical container, 2 is a stirring blade, 3 is a fixed fin, 4 is a solid particle (powder), 5 is a motor, 6 is a stirring shaft, 7 is a cylindrical container stand, 8 is a cylindrical stand, 9 is a floor,
10 is a spray nozzle, 11 is a coating liquid storage tank, 12 is a pump, 13 is a flow meter, 14 is a meter, 15
Is a three-way valve, 16 is an exhaust device, 17 is a flange, 18
Is a coating liquid supply pipe, and 19 is a granulation coating discharge port. Solid particles, that is, powder 4 is charged into the cylindrical container 1, and the stirring blade 2 has the stirring blade shaft 6 of the motor 5 at the bottom thereof.
, And the mixture is shear mixed with the fixed fins 3 arranged at the bottom of the cylindrical container 1 to perform convective mixing by itself. That is, the solid particles 4 are mixed in the direction of A in the figure. The spray nozzles 10 are uniformly arranged on the ceiling of the cylindrical container 1, the coating liquid stored in the coating storage tank 11 is pumped by the pump 12, and the coating liquid is sprayed from the spray nozzle 10 onto the fixed particles 4. It

FIG. 2 is a view showing an example of the spray nozzle 10,
The spray nozzle 10 has a supply inlet 102 into which a coating liquid is supplied, and a surface facing the supply inlet 102 has a spherical surface 10.
4 has a container, and the spherical surface has an ejection port 103 which is perpendicular to the spherical surface 104 and spreads toward the inside of the container.
The ejection ports 103 are arranged concentrically with respect to the spherical surface 104. The coating liquid forms a continuous thread-like flow 101 due to the shape of the ejection port and is sprayed on the powder. In addition,
The coating liquid is measured by the flow meter 13 and the meter 14
Is supplied through a three-way valve 15 which is controlled to be opened and closed by the quantitative meter 14 is set to a fixed flow rate with respect to the solid particles 4, and the flow rate signal from the flow meter 13 is counted,
When the count value reaches the set value, the three-way valve 15 is closed and the supply of the coating liquid is stopped. However, after the valve is closed, the coating liquid remaining in the pipe 18 causes dripping, which becomes large particles in the solid particles and falls, causing non-uniform mixing and causing defective coating. Therefore, in order to prevent this, the three-way valve is used. 15 is switched to send compressed air under pressure, and piping 1
The coating liquid remaining in 8 is dropped. Further, some of the fixed particles that are scattered are removed by the exhaust device 16 from the flange 17
Is discharged through.

Effect According to the present invention described above, a granulation coating having a uniform and narrow fineness distribution can be obtained, and the granulation time, which conventionally required 90 minutes, can be reduced to 15 minutes.

[Brief description of drawings]

FIG. 1 is a configuration diagram for explaining an embodiment of a granulation coating device according to the present invention, and FIG. 2 is a diagram showing an example of a spray nozzle. 1 ... Cylindrical container, 2 ... Stirring blade, 3 ... Fixed fin, 4 ... Solid particles (powder), 5 ... Motor, 6 ... Stirring blade axis, 7 ... Cylindrical container stand, 8 ... Cylindrical stand, 9 ……
Floor, 10 ... Spray nozzle, 11 ... Coating liquid storage tank, 12 ... Pump, 13 ... Flowmeter, 14 ...
Quantitative meter, 15 ... 3-way valve, 16 ... Exhaust device, 17
...... Flange, 18 …… Coating liquid supply pipe, 19 ……
Granulation coating outlet, 101 ... Coating liquid, 10
2 ... inlet, 103 ... jet, 104 ... spherical surface.

Claims (3)

[Claims] 1. A predetermined amount of powder is stored in a cylindrical container, a granulation coating liquid is sprayed at a constant ratio to the powder, and the stirring fins and fixed fins rotating in the cylinder are used. In a granulation coating apparatus for performing flow shear mixing of powder and convective mixing to granulate and coat powder, the coating liquid is made into continuous filamentous water from a plurality of nozzles arranged on the ceiling of the cylindrical container to form powder. A granulating coating device characterized by being sprayed on. 2. The nozzle granulation coating liquid comprises a feed inlet and a container whose surface facing the feed inlet is a spherical surface, and the spherical surface extends inward perpendicularly to the spherical surface. The granulating and coating apparatus according to claim (1), wherein the granulating and coating device has an ejection port, and the ejection ports are concentrically arranged and perforated with respect to the spherical surface. 3. The granulation coating liquid is integrated by a flow rate signal, and is integrated by a quantitative integrator that closes a valve at a predetermined amount to supply the liquid to the nozzle. The liquid supply closing signal at a predetermined amount is used to supply the nozzle. The granulation coating apparatus according to claim (1) or (2), characterized in that air is pressure-fed to the container to prevent dripping into the cylindrical container.