JPS5933414B2 - Granulator - Google Patents

Description

[Detailed description of the invention] The present invention relates to a particle granulation device.

More specifically, a liquid such as a solution suspension or a molten liquid (hereinafter simply referred to as "liquid") is sprayed into granules flowing with gas to obtain granules or m& granules (hereinafter simply referred to as "liquid"). This relates to a device called a granulator.

Currently, methods for obtaining granules using fluidized beds and spouted beds are known.

However, in methods that use a fluidized bed, the wind speed in the bed is generally slow, so particles tend to adhere to each other and form agglomerates, and the fluidization state is often forced to stop due to agglomerates. is not an appropriate method.

Also known are methods using a spouted bed, as disclosed in Japanese Patent Publication No. 38-13896 and U.S. Pat. Nos. 2,786,280 and 3,231,413.

However, in these methods, when large particles are generated, there is no way to remove them, and the jet orifice is often closed, which is considered to be an illegal drawback.

Although the apparatus of the present invention and the method using the same utilize a spouted bed, they do not have the above-mentioned drawbacks and can continuously obtain uniform particles of a desired size in a stable state. be.

Hereinafter, explanation will be given using the apparatus of the present invention.

Figures 1 to 5 show five embodiments of a main body 1 capable of performing a granulation operation (however, the upper part is omitted in Figures 2 to 5).

) Figure 6 shows a flow sheet for the wooden core device.

In FIG. 1, a main body 1 is an airtight container in which a vertical cylindrical peripheral wall 2 is joined to an inclined bottom plate 3 and a top plate 4, and a gas exhaust port 5 and a bottom plate 3 are provided at the top or top of the peripheral wall 2. A powder discharge port 6 is provided at the bottom of the chamber.

A cylindrical gas ejection pipe 7 is vertically fixed to the bottom plate 3 with its central axis almost coinciding with the peripheral wall 2 and slightly protrudes from the bottom plate 3, and a conical body 8 is joined to the top end of the ejection pipe 7 so as to open upward. has been done.

The diameter of the upper end of the conical body 8 is usually smaller than the inner wall of the peripheral wall 2 so that the flowing powder can uniformly overflow from the upper peripheral part, but as shown in FIG. The cone body 8 may have a large diameter and be joined to the inner surface of the peripheral wall 2, and a plurality of holes or horizontal slits may be opened in horizontal and symmetrical positions in the cone body 8. Alternatively, as shown in FIG. 8A
can also be installed.

A gas outlet 9 is provided at the lowest end of the gas ejection pipe 7, a gas population 10 is provided at the bottom, and a liquid inlet pipe is provided at the top such that a liquid spray nozzle 11A sprays upward at the bottom of the cone 8. 11 is installed.

To supply powder and granules to the granulator 1, normally a powder supply pipe 12 is provided so that the powder can be fed toward a gas jet port as shown in FIG. It can also be mounted above the gas population 10 of 7.

Note that it is better to provide a conical shaft plate 13 to prevent the powder and granules spouted up within the peripheral wall 2 from falling along the inner surface of the peripheral wall 2 to the bottom 3. In the case where the body 8 is opened, the shaft plate 13 can be omitted.

Figures 4 and 5 show a granulator with multiple nozzles.

In the granulator shown in FIG. 4, the liquid feed pipe 11 can vertically communicate with a plurality of branch pipes 11C to a ring-shaped header pipe 11B as shown in FIG. The same number of nozzles IIA are attached to the tip of the branch pipe 11C, and in FIG. 5 and FIG. tube 11
As shown in FIG. 5A, the branch pipes 11C are fixed on a straight line at approximately equal intervals, and the nozzle 11A is attached to the tip of the branch pipe 11C.

The gas ejection pipe 7A has a rectangular horizontal cross section or an oval shape with semicircles connected to opposite sides of the rectangle, and the tip thereof is a pyramid or a cone with an oval horizontal cross section and a flat plate joined together. 8B is fixed to open upward.

The peripheral wall 2 and the shaft plate 13A also have a rectangular or oval horizontal cross section.

Although the structure of the five embodiments of main body 1 has been shown above,
The one in Figure 1 shows the most standard structure, the one in Figure 2 has a large amount of retention in the spouted bed and is used when this is desired to be adjusted, and the one in Figure 3 shows the structure in Figure 1. It is used when you want to increase the retention amount a little more than the normal amount.

4, 5, and 5A are used when the production volume is large, and the one shown in FIG. 4 has the advantage that it is easier to manufacture and maintain, and it is easier to manufacture large-capacity products.

A granulation method using the granulator main body 1 of the present invention will be explained with reference to the flow sheet of FIG. 6, which is an example.

First, the rotary valves 21, 22, and 23 are operated, and the blower 24 is operated to introduce air A into the main body 1 from the gas population 10, and discharge it through the dust collector 25 and scrubber 26.

In this case, cold air is sent when the liquid to be sprayed is a melt, and hot air is sent when the liquid is a solution or suspension.

After that, a vibrating sieve 27 having two sieve meshes, a distributor 28,
Crusher 29, conveyor 30, cooler 31, conveyor 3
2 is moved to supply the powder to the main body 1 to form a spouted bed.

In this embodiment, a cooler 31 is provided, but this is necessary to spray a molten liquid such as urea to maintain a constant temperature in the spouted bed or to increase production, and is generally unnecessary. be.

Although not shown in this flow sheet, in the case of dry granulation which requires hot air, a gas heater is added in front of the gas inlet 10.

Now, gradually increase the amount of powder supplied to main body 1,
Powder begins to overflow from the cone 8, and when the ratio of the supply amount to the liquid feeding amount (circulation ratio) reaches a predetermined value, the liquid is fed.

When the amount of powder that is circulated and supplied is small compared to the amount of liquid sent, the amount of liquid that adheres to the powder surface is large, and when the liquid is a solution or suspension, drying is not done sufficiently, and the liquid If it is a molten liquid, it will not be sufficiently cooled and solidified.

Conversely, when the amount of circulation is large, the amount of adhesion is small, so drying or cooling is done quickly, the surface of the particles is not smooth, and the equipment and power required for circulation are all large, which is uneconomical. .

Therefore, there is an appropriate circulation ratio, which is 1 to 5
Operates with twice the circulation volume.

The powder and granules discharged from the rotary valve provided at the powder discharge port 6 are separated into three types by a vibrating sieve 27: those within the desired particle size range, larger particles, and smaller particles. A certain amount of particles within the particle size range is extracted as product P using the cushion tank 28, and the remaining part is returned to the system via the conveyor 30 in order to stabilize the particle size distribution and circulation amount within the system. The particles larger than the particle size are put into the crusher 29 and crushed to have an appropriate particle size distribution in order to become cores for granulation. They are also put into the conveyor 30 and circulated together with the small diameter particles.

As mentioned above, the cooler 31 is necessary to increase the performance when spraying the melt, and cools the temperature of the powder and granular material supplied to the main body 1 to a predetermined temperature in order to keep the temperature in the spouted bed constant. However, it is also used when dry granulation is performed by solution spraying and it needs to be cooled, and if it is better to quickly cool it down after granulation, it is installed at the main body's powder waste outlet. It is more appropriate to provide it immediately after the outlet 6.

Therefore, the type of cooler 31 is selected depending on the cooling temperature of the granules, the amount of the granules, and the type and temperature of the cooling fluid. , rotating cylindrical and channel coolers are suitable.

The powder and granules leaving the cooler 31 are conveyed to the main body 1 by a conveyor 32.
The powder is fed into the spouted bed through the powder supply port 12.

Now, in the conical body 8 in the main body 1, the powder is fluidized by the air ejected from the ejection pipe 7, and at the same time, the liquid sprayed from the center of the ejection pipe 7 adheres to the surface of the powder and is dried or solidified by cooling. As the surface temperature measurement progresses and the grains grow, the cone 8
The particles uniformly overflow and are discharged from the upper layer of the cone 8, and if the particles become thick within the cone body 8 and cannot be supported by the jet force of the gas, they pass through the jet pipe 7 and are taken out from the discharge port 9.

The fluid taken out from the discharge port 9 is put into the vibrating sieve 27 and collected by the dust collector 25, and the powder discharged from the low-resolution valve 23 is returned to the main body 1.

As mentioned above, the granules discharged from the main body 1 are passed through the vibrating sieve 27.
, the cushion tank 28, and the crusher 29 and the flow, the granules taken out as products are in the desired particle size range, and the granules that are circulated and returned to the main body 1 have the number of nuclei and particle size distribution. is controlled, the granulation operation in the main body 1 is carried out smoothly and smoothly, creating the basis for obtaining good granules.

In addition, the structure of the main body 1 allows the flow and perfusion of particles to be uniform due to the structure of the cone 8 and the ejection tube 7 as described above, so that the growth of particles is limited to particles in a specific part of the container. Since the process is carried out uniformly and the amount of powder and granules supplied to the cone 8 is adjusted such as the particle size distribution, the surface of the product particles is smooth and glossy, and the shape is close to the desired shape. The granulation process is stable and can be carried out continuously.

[Brief explanation of the drawing]

1 to 5 are explanatory diagrams of five embodiments of the granulator of the present invention, and FIG. 6 is a flow sheet of the granulation method using the granulator of the present invention. 1... Granulator main body, 2... Peripheral wall, 3.
...Bottom plate, 4...Top plate, 5...
Gas discharge port, 6... Powder discharge port, 1...
・・Gas ejection pipe, 8・・・・Cone, 9・・・・
・ Soul-like body outlet, 10... Gas inlet, 11...
...Liquid feed pipe, 12...Powder supply port, 1
3...Shaft plate, 21, 22, 23...Rotary valve, 24...Blower, 25...
... Dust collector, 26 ... Scrubber, 27.
... Vibration sieve, 28 ... Distributor, 29 ...
...Crusher, 30/32...Conveyor, 3
1... Cooler.

Claims (1)

[Scope of Claims] 1. A container in which an inclined bottom plate is joined to a vertical cylindrical peripheral wall having a top plate, and a gas exhaust port is provided at the top and a powder discharge port is provided at the bottom end. An ejection pipe is fixed vertically with a slightly protruding part, a cone whose maximum diameter is smaller than the inner diameter of the peripheral wall is joined to the upper end of the ejection pipe in an upwardly open shape, and a lump discharge port is connected to the lower end of the ejection pipe. A gas inlet is installed slightly above the discharge port, and a liquid feeding pipe having a nozzle whose tip sprays liquid upward at the lower part of the cone is installed above the jet pipe, and the gas is jetted from the peripheral wall or A granulator with a structure in which a powder supply pipe is provided almost in the center of the pipe. 2. The granulator according to claim 1, wherein the cone has a maximum diameter of a dog, is joined to the inner surface of the peripheral wall, and has a plurality of holes or horizontal slits opened in the same horizontal and symmetrical position. 3. The granulator according to claim 1, wherein a band-shaped ring is fixed to the upper end of the conical body. 4. Claim 1, wherein the liquid feed pipe has a structure in which a plurality of branch pipes are fixed to a ring-shaped header pipe so as to be vertically connected to each other, and a liquid spray nozzle is added to the tip of the branch pipes. Granulator as described. 5. The liquid feed pipe has a structure in which a straight header pipe is installed, and a plurality of branch pipes each having a liquid spray nozzle at the tip are installed at approximately equal intervals, and the horizontal cross section of the gas ejection pipe is rectangular;
The granulator according to claim 1, wherein a pyramid is fixed to the tip of the granulator so as to open upward, and the horizontal cross section of the peripheral wall and the shaft plate is rectangular. 6 The horizontal cross section of the gas ejection pipe is oval, a cone made by joining a cone and a flat plate with an oval horizontal cross section is fixed to the tip of this cone with an upward opening, and the horizontal cross section of the peripheral wall and shaft plate is oval. A granulator as claimed in claim 5.