JPH09220460A - Cooling and granulating method and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce granulated powder in spherical particles and having fine powder only on the surface by adopting a rotary disc system or a nozzle system as an atomizing means for a raw material to introduce a warm wind to the peripheral part of the rotary disc or the nozzle and exhausting it from the upper part of equipment or the side part of equipment. SOLUTION: In the upper part of a cooling and granulating chamber 10, an atomizing means 11 of rotary disc type for a raw material A is installed. When the raw material A is atomized in the radial direction by the atomizing means 11, a warm wind C is introduced from the peripheral part of the atomizing means 11 by a warm wind introducing means 12 to heighten the temperature of the peripheral part of the atomizing means 11. Then, the temperature of the peripheral part of the atomizing means 11 is heightened to restrain the gelation velocity of the atomized liquid, allowing spherical liquid droplets to be formed. The spherical liquid droplets come into contact with fine particles 2 and fine particles 14 to form granulated powder in spherical particles only whose surface is dusted with fine powder.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a material containing ingredients such as foods, feeds and pharmaceuticals, which is gelled by cooling, is sprayed as a liquid material by heating, and is cooled by cold air to accelerate gelation. The present invention relates to a cooling granulation method and apparatus capable of sprinkling (adhering) predetermined fine powder on the surface of gel-like fine particles to prevent the fine particles from adhering to the wall surface of the apparatus and obtaining granules that are easy to handle.

[0002]

2. Description of the Related Art Conventionally, a cooling granulating apparatus as shown in FIG. 8 has been known. In this apparatus, a stock solution A which is made into a liquid by heating a substance which is gelated by cooling is atomized by a spray disc 1, and the spray liquid is cooled by a cold air B introduced from the lower part of the apparatus to form gel fine particles. (Granule),
The gel-like fine particles and the fine powder 2 such as starch and silica fluidized by the cold air B in the lower part of the apparatus are brought into contact with each other to produce a granular product in which the fine powder is attached to the gel-like fine particles (Japanese Patent Publication No. 45-10958). Publication, Japanese Patent Publication No. 4-2868
No. 4 and Special Table Sho 64-500197, etc.).

However, in the apparatus shown in FIG. 8, when a substance that gels by cooling is heated and atomized into a liquid substance, an air flow is generated by the flow of spray droplets and the surrounding cooling air is involved. The sprayed portion of the spraying disc 1 and the sprayed liquid are cooled, the liquid viscosity increases, and it becomes difficult to atomize the sprayed particles. In addition, irregular shaped objects such as fibrous materials as shown in FIG. 9 sometimes occur. Also, when the stock solution is heated to a high temperature,
Since the granules come into contact with the fine powder while the gelation of the granules is insufficient, as shown in FIG.
There is a problem that the fine powder 2 also enters the inside, and the amount of fine powder in the produced granules is increased to lower the content of the main component.

In order to solve the above-mentioned problems, if the amount of fine powder supplied into the apparatus is reduced, a sticky state remains on the surface of the granules, causing a problem that unsolidified matter adheres to the wall surface of the apparatus. In particular, in the spraying method using a rotating disk as the spray atomizing means, since the stock solution is atomized and atomized by using centrifugal force, droplets are scattered in the radial direction from the rotating disk and pass through a thin portion of fine powder. . Therefore, as shown in FIG.
A large amount of adhering products in the form of strips on the device wall around the rotating disk 3
There has occurred.

As described above, in the spraying method using the rotating disk, there is little chance that the liquid droplets come into contact with the fine powder, and it is difficult to evenly apply the fine powder to the entire surface of the granule. There is a problem in that a device having a large diameter is required to avoid the adhesion.

Further, in the conventional cooling granulating apparatus as shown in FIG. 8, since the cooling air and the flowing air are both used, the cooling and gelling of the sprayed droplets and the flow of the fine powder are performed. There is a problem that the optimum amount of air and the range of the air temperature are small, and it is difficult to select the range. Further, in the conventional apparatus shown in FIG. 8, a large amount of the fine powder 2 is accumulated in the fluidized bed provided at the lower portion of the apparatus, so that the fine powder 2 is fluidized by a large amount of the cold air B. An excessive amount of fine powder is required with respect to the amount used, which causes a problem that equipment such as a blower, an exhaust fan, and a refrigerator becomes large.

[0007]

Therefore, the present invention has been made in view of the above-mentioned conventional problems, and it is possible to produce granules having a spherical shape and having fine powder adhered only on the surface thereof. An object of the present invention is to provide a cooling granulation method and apparatus in which the control range of the amount and temperature of the cooling granulation gas is large and easy.

[0008]

That is, according to the present invention, a stock solution which is liquefied by heating a substance that gels by cooling is atomized into fine particles, and fine powder finer than fine particles is sprayed in the lower part of the apparatus. A fluidized bed is formed, and the spray liquid is cooled from the lower part of the apparatus by cold air introduced into the fluidized bed to form fine gel particles, and the fine gel particles come into contact with the fine powder in the fluidized bed to form fine gel particles. A cooling granulation method for producing a granular product in which fine powder is adhered to, while adopting a rotating disk method or a nozzle method as a spray atomizing means for the stock solution, and applying hot air to the peripheral portion of the rotating disk or nozzle. Provided is a cooling granulation method, which comprises introducing and evacuating from an upper part or a side part of the device.

According to the present invention, the cooling granulation chamber, the atomizing atomizing means of the rotary disc type or the nozzle type installed on the upper part of the cooling granulating chamber, and the peripheral portion of the atomizing atomizing means are heated. A warm air introduction means for introducing air, and a fluidized bed formed in the lower part of the cooling granulation chamber, which fluidizes the fine powder with cold air,
There is provided a cooling granulating device, comprising:

In the present invention, it is preferable that the hot air introduced into the peripheral portion of the spray atomizing means has a temperature equal to or higher than the gelling temperature of the stock solution, from the viewpoint of suitable cooling and gelling of the spray solution. In addition to the cold air for fluidizing the fluidized bed, introducing cold air for cooling the spray liquid from the lower part of the device increases the control range of the cool air amount and the cool air temperature that optimize the cooling gelation of the spray liquid. Therefore, it is preferable because control can be easily performed. Further, it is preferable to introduce fine powder into the device from the outside so that the fine powder concentration on the wall surface of the device becomes high. Further, in this case, the device can be downsized.

Further, by increasing the fluidizing air velocity of the fluidized bed formed in the lower part of the cooling granulation chamber, the fine powder in the fluidized bed is blown away, and a coarse classification means for leaving granules having a larger particle size than the fine powder, and a coarse classification. It is preferable that the granules are roughly classified and dried in the same apparatus by providing a drying means for drying the remaining granules roughly classified by the means with hot air. In addition, exhaust from the top or side of the device,
It can also be circulated and used by a circulation means.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, a rotating disk system or a nozzle system is adopted as a spray atomizing means for a stock solution, hot air is introduced into the peripheral part of the rotating disk or nozzle, and the upper part of the device or the side part of the device. Exhausted from. Therefore, as the temperature distribution in the apparatus, as shown in FIG. 2, the temperature of the spray atomization portion becomes high and the gelation rate of the stock solution is suppressed, so that spherical droplets are formed by surface tension, The spherical droplets come into contact with cold air and fine powder to generate a spherical granular product in which the fine powder adheres only to the surface as shown in FIG.

FIG. 1 is an explanatory view showing an example of a cooling granulation apparatus according to the present invention, 10 is a cooling granulation chamber, and an upper part of the cooling granulation chamber 10 is a stock solution A of a rotating disk system. A spray atomization means 11 is installed. A warm air introducing means 12 for introducing a warm air C is provided in the peripheral portion of the atomizing and atomizing means 11, and in the lower part of the cooling granulating chamber 10, the fine powder 2 is fluidized on the perforated plate 21 by the cold air B. A fluidized bed 13 is formed.

On the side of the cooling granulation chamber 10, a fine powder 14 different from the fine powder 2 fluidized in the fluidized bed 13 is provided.
There is provided a fine powder introducing means 15 for introducing the fine powder. Further, an exhaust port 16 is provided at the top of the cooling granulation chamber 10, the exhaust air accompanied with a small amount of fine powder is discharged, and solid particles are separated by a cyclone 17, and the fine powder is on the side of the cooling granulation chamber 10. The gas is reintroduced from the section 18, while the gas is discharged to the outside air through the bag filter 19 and the exhaust blower 20.

When the stock solution A is sprayed in the radial direction by the spray atomizing means 11, warm air C is introduced from the peripheral part of the spray atomizing means 11 by the hot air introducing means 12, and the peripheral part of the spray atomizing means 11 is introduced. Raise the temperature of. Then, as shown in FIG. 2, the temperature of the peripheral portion of the spray atomizing means 11 rises and the gelation rate of the spray liquid is suppressed, whereby spherical droplets are formed, and the spherical droplets are formed. In contact with the cold air B and the fine powder 2 and the fine powder 14, a spherical granular material in which the fine powder is sprinkled only on the surface is generated.

The spherical granules produced are then coarsely classified and dried. Coarse classification is a granular material (particle size 100-
500 μm) and fine powder of the fluidized bed 13 (particle size 10 to 50)
difference in terminal sedimentation velocity (due to differences in particle size)
By increasing the fluidizing air velocity of the cold air blown into the fluidized bed 13, fine powder is blown away, and coarse classification is performed in which only granular material having a particle size larger than that of the fine powder is left in the bed. After the coarse classification, hot air is introduced in place of the cold fluidizing air of the fluidized bed 13 to dry the granular material. Next, this is passed through a classifying means 26 such as a sieve to obtain a product.

In the present invention, as shown in FIG. 2, both the warm air C and the cold air B are introduced in a swirling flow, and the spray atomization means 1 is used.
The temperature distribution in the apparatus (cooling granulation chamber) 10 is set such that the temperature of the peripheral portion of 1 is high and the temperatures of the peripheral portion and the lower portion (bottom portion) thereof are low. Further, in the present invention,
The fine powder 14 is introduced into the cooling granulation chamber 10 from the outside so that the fine powder has a high concentration in the wall surface portion of the apparatus (cooling granulation chamber) 10, and the peripheral portion of the spray atomization means 11 of the stock solution A is the fine powder 2 , 14 became a dilute atmosphere, and the sprayed droplets were brought into contact with the fine powders 2, 14 in a state where gelation proceeded to some extent. For this reason, the fine particles can be attached to the surface of the gel-like fine particles (granules) almost in one layer without the droplets adhering to the wall surface of the apparatus, and the content rate of the main component of the obtained granular product can be increased. In addition, the consumption of fine powder can be reduced.

As a method of supplying the fine powder 14, as shown in FIG. 4, a powder nozzle 22 having an empty cone spray pattern.
5, or a method of supplying in a tangential direction from the conical portion 23 or the straight body portion 24 of the cooling granulation chamber 10 as shown in FIG. 5 is preferable.

In the cooling granulating apparatus of the present invention, as a structure of the fluidized bed 13 formed in the lower part, as shown in FIG. 6, the sub-cooled air F is introduced from the lower part of the perforated plate 21 to fluidize the fine powder 2 and fluidized bed. 13 is formed, a supply pipe 25 for the main cold air E is provided through the perforated plate 21, and a umbrella member 27 is provided above the cold air blowout portion of the supply pipe 25, or, as shown in FIG. 7, A structure in which a swirl slit 28 is installed above the fluidized bed 13 to generate a swirl flow is desirable. As shown in FIGS. 6 to 7, if the fluidized bed portion is formed smaller than the conventional one, and the cold air blowing speed is set to be the minimum fluidizing air speed or more, preferably 10 times or more, and the cold air blowing portion has a structure that causes a swirling flow, fine powder is generated. The concentration becomes high on the wall surface of the cooling granulation chamber 10, which is preferable.

Examples of the substance which gels upon cooling used in the present invention include proteins such as gelatin and casein,
Polymeric compounds such as gum arabic, cellulose compounds, dextrins, polysaccharides, polyvinyl alcohol (PVA), hydroxypropyl cellulose (HPC) and the like can be mentioned. Examples of the substance dispersed in the gelling substance include water-soluble vitamins such as vitamin C, vitamin B1 and vitamin B6, fat-soluble vitamins such as vitamin A, vitamin D and vitamin E, essential oils, foods, feeds, Pharmaceuticals, agricultural chemicals, pigments, etc. can be mentioned.

Examples of the fine powder adhering to the surface of the gelled fine particles include silica, sodium silicate, calcium silicate, carbon, talc, alumina and starch. The amount adhered to the surface of the gel particles is the minimum amount, and it is desirable that the gel particles further adhere to the surface of the gel particles as much as possible. For that purpose, dispersibility of fine powder, good fluidity, and fine particle size, for example, 1/10 of gel-like particles
The following particle sizes are desirable.

In the present invention, cold air used for fluidizing the fine powder, cooling the spray liquid, or hot air introduced into the peripheral portion of the spray atomizing means may be air, nitrogen gas, carbon dioxide gas, argon gas, or helium. Gas or the like can be used. In addition, the exhaust from the device (cooling granulation chamber) is shown in FIG.
As shown in FIG. 5, it can be circulated and used as cold air or hot air through the cyclone 17, the bag filter 19, the exhaust blower 20, the refrigerator 29, the heater 30, and the like.

The temperature of the cold air or the warm air is determined in relation to the gelling temperature of the stock solution, but the temperature of the hot air is preferably a temperature above the gelling temperature of the stock solution, for example, the gelling temperature of the stock solution. In the case of 40 ° C, the warm air temperature is preferably 40 to 110 ° C, more preferably 40 to 90 ° C. The cold air temperature is preferably -5 to 30 ° C, more preferably 5 to 20 ° C.

[0024]

The present invention will be described in more detail based on the following examples, but the invention is not intended to be limited to these examples.

Example 1 57 parts by weight of gelatin was added to 259 parts by weight of water while stirring and swelled for 1 hour. 52 parts by weight of vitamin A acetate (2.8 × 10 ⁶ international units / g) which had been melted at 65 ° C. in advance, 10 parts by weight of ethoxyquin and 17 parts by weight of glycerin were mixed and emulsified at 60 to 65 ° C. Hot air was introduced at 60 ° C. into the peripheral portion of the rotating disk selected as the atomizing means for atomization, and the rotation speed was adjusted to 5000 rpm. From the bottom of the cooling granulation chamber,
Cold exhaust from a device for circulation and reuse was put in, and the temperature in the cooling granulation chamber was adjusted to 10 to 15 ° C.

In the above, the above emulsion was sprayed on a rotating disk. During the spraying, at the same time, corn starch was introduced tangentially from the conical portion of the cooling granulation chamber so that the starch concentration on the inner wall of the cooling granulation chamber became thick. After spraying a predetermined amount of emulsion and increasing the amount of cold air from the lower part of the cooling granulation chamber, the obtained granules and fine powder are roughly classified, and then hot air heated to 80 to 90 ° C by a heater from cold air. And was dried. A small amount of the dried fine powder and granules was taken out from the apparatus, and the fine powder and granules were precisely classified by a sieve.
The obtained granules were free-flowing spherical granules having an average particle diameter of 237 μm and had a vitamin A content of 793,000 international units / g.

EXAMPLE 2 75 parts by weight of gelatin was added to 360 parts by weight of water with stirring to swell for 1 hour, 67 parts by weight of dextrin was further added, and vitamin A acetate 52 was melted at 65 ° C. in advance. Parts by weight (2.8 × 10 ⁶ international units / g) and 2 parts by weight of dl-α-tocophenol were mixed and emulsified at 60 to 65 ° C. Granules were obtained from this emulsion by the same procedure as in Example 1. The obtained granules were free-flowing spherical granules having an average particle diameter of 240 μm and had a vitamin A content of 530000 international units / g.

(Comparative Example 1) The temperature in the cooling granulation chamber was adjusted to 10 to 15 ° C without introducing hot air into the peripheral portion of the rotating disk, and then an emulsion having the same composition as in Example 1 was used. When spraying was carried out with the rotation speed of the rotating disk set at 5000 rpm, a fibrous amorphous product was generated and spraying was impossible.

(Example 3) 8 parts by weight of 450 parts by weight of soybean hydrogenated oil
Melt at 0 ° C., mix with 50 parts by weight of a lipophilic surfactant, and further mix 550 parts by weight of L-ascorbic acid,
It was emulsified at 80 ° C. Oil-and-fat coated particles were obtained from this emulsion by a known spray granulation method. Next, 25 parts by weight of gelatin was added to 475 parts by weight of water with stirring and dissolved at 50 ° C. Further, 100 parts by weight of the above oil-and-fat coated particles were dispersed in a gelatin solution. Water-soluble vitamin granules were obtained from this dispersion by the same procedure as in Example 1. The obtained granules were free-flowing spherical granules having an average particle diameter of 280 μm, and the L-ascorbic acid content was 20%.

Example 4 8 parts by weight of 450 parts by weight of soybean hydrogenated oil
Melt at 0 ° C, mix with 50 parts by weight of lipophilic surfactant and 550 parts by weight of thiamine nitrate and mix at 80 ° C.
And emulsified. Oil-and-fat coated particles were obtained from this emulsion by a known spray granulation method. Next, 25 parts by weight of gelatin was added to 475 parts by weight of water with stirring and dissolved at 50 ° C. Further, 100 parts by weight of the above particles were dispersed in a gelatin solution. Water-soluble vitamin granules were obtained from this dispersion by the same procedure as in Example 1. The obtained granules are free-flowing spherical granules having an average particle size of 270 μm and a thiamine nitrate content of 30%.
Met.

(Example 5) 8 parts by weight of 450 parts by weight of soybean hydrogenated oil
Melt at 0 ° C., mix with 50 parts by weight of lipophilic surfactant and 550 parts by weight of pyridoxine hydrochloride,
Emulsified at 0 ° C. Oil-and-fat coated particles were obtained from this emulsion by a known spray granulation method. Next, 25 parts by weight of gelatin was added to 475 parts by weight of water with stirring and dissolved at 50 ° C. Further, 100 parts by weight of the above particles were dispersed in a gelatin solution. Water-soluble vitamin granules were obtained from this dispersion by the same procedure as in Example 1. The obtained granules have an average particle size of 270μ.
m free-flowing spherical granules with a pyridoxine hydrochloride content of 30%.

Comparative Example 2 450 parts by weight of soybean hydrogenated oil was added to 8 parts.
Melt at 0 ° C., mix with 50 parts by weight of a lipophilic surfactant, and further mix 550 parts by weight of L-ascorbic acid,
It was emulsified at 80 ° C. Oil-and-fat coated particles were obtained from this emulsion by a known spray granulation method.

Comparative Example 3 450 parts by weight of hydrogenated soybean oil was added to 8 parts.
Melt at 0 ° C, mix with 50 parts by weight of lipophilic surfactant and 550 parts by weight of thiamine nitrate and mix at 80 ° C.
And emulsified. Oil-and-fat coated particles were obtained from this emulsion by a known spray granulation method.

Comparative Example 4 450 parts by weight of soybean hydrogenated oil was added to 8 parts.
Melt at 0 ° C., mix with 50 parts by weight of lipophilic surfactant and 550 parts by weight of pyridoxine hydrochloride,
Emulsified at 0 ° C. Oil-and-fat coated particles were obtained from this emulsion by a known spray granulation method.

Test Example 1 A compression test was carried out on the water-soluble vitamin granules obtained in Examples 3 to 5 and the oil-and-fat coated particles obtained in Comparative Examples 2 to 4. In the test, about 30 g of water-soluble vitamin granules or oil-coated particles were weighed into an autograph (Shimadzu Autograph AG-5000 type), and 1.
It was carried out by a method of applying a load of 7 kg / cm ² and maintaining it for 5 minutes. Table 1 shows the results.

[0036]

[Table 1]

Test Example 2 Sensory tests were conducted on the water-soluble vitamin granules obtained in Examples 4-5. In the test, 50 mg of the granules obtained in the examples (thiamin nitrate and pyridoxine hydrochloride content were 30%), and 15 mg of thiamine nitrate (Japanese Pharmacopoeia) and pyridoxine hydrochloride (Japanese Pharmacopoeia) selected as controls were taken in the mouth. After containing for 10 seconds, it was taken with 100 ml of water, and the degree of bitterness (thiamine nitrate) and astringency (pyridoxine hydrochloride) at this time was expressed as ± to ++. The results are shown in Table 2.
Shown in

[0038]

[Table 2]

[0039]

As described above, according to the present invention,
Regardless of whether the device is large or small, it is possible to manufacture granules with spherical shape and fine powder only on the surface with less loss, and control range of cooling granulation gas amount and temperature. Is large, and therefore the control is easy.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an example of a cooling granulating apparatus according to the present invention.

FIG. 2 is a schematic diagram showing the temperature distribution inside the cooling granulating apparatus according to the present invention.

FIG. 3 is a cross-sectional view showing an example of a granular product manufactured according to the present invention.

FIG. 4 is an explanatory diagram showing an example of a method of supplying fine powder from the outside.

FIG. 5 is an explanatory diagram showing another example of a method of supplying fine powder from the outside.

FIG. 6 is a cross-sectional explanatory view showing an example of a fluidized bed formed in the lower part of the device of the present invention.

FIG. 7 is a cross-sectional explanatory view showing another example of the fluidized bed formed in the lower portion of the device of the present invention.

FIG. 8 is a cross-sectional explanatory view showing an example of a conventional cooling granulating apparatus.

FIG. 9 is a cross-sectional view showing an example of a granular product manufactured by a conventional device.

FIG. 10 is a cross-sectional view showing another example of a granular product manufactured by a conventional device.

[Description of sign]

2 ... Fine powder, 10 ... Cooling granulation chamber, 11 ... Rotating disc type spray atomizing means, 12 ... Warm air introducing means, 13 ... Fluidized bed, 1
4 ... Fine powder, 15 ... Fine powder introducing means, 16 ... Exhaust port, 17 ...
Cyclone, 18 ... Side part of cooling granulation chamber, 19 ... Bag filter, 20 ... Exhaust blower, 21 ... Perforated plate.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI Technical display location // A23L 1/06 A23L 1/06 (72) Inventor Mitsunori Tanabe 2 Takatsuki South, Tadaoka-cho, Senboku-gun, Osaka Prefecture No. 7-19 (72) Inventor Takashi Ito 3847 Ikebe-cho, Tsuzuki-ku, Yokohama-shi, Kanagawa Okawara Kakoki Co., Ltd. (72) Minoru Koganei 3847 Ikebe-cho, Tsuzuki-ku, Yokohama, Kanagawa (72) Inventor Tetsuo Yokoyama 3847 Ikebe-cho, Tsuzuki-ku, Yokohama-shi, Kanagawa Okawara Kakoki Co., Ltd.

Claims (9)

[Claims] 1. A liquid material which is made into a liquid by heating a substance which gels by cooling is atomized into fine particles, and a fluidized bed made of fine powder finer than the atomized fine particles is formed in the lower portion of the apparatus, and the fluidized layer is formed from the lower portion of the apparatus. The spray liquid is cooled by the cold air introduced through the layer to form gel fine particles, and the gel fine particles come into contact with the fine powder in the fluidized bed to produce a granular product in which the fine powder is attached to the gel fine particles. A granulation method, which employs a rotating disk system or a nozzle system as the spray atomizing means of the stock solution, introduces hot air into the peripheral part of the rotating disk or the nozzle, and from the device upper part or the device side part. A cooling granulation method characterized by exhausting. 2. The cooling granulation method according to claim 1, wherein the hot air introduced into the peripheral portion of the spray atomization means has a temperature equal to or higher than the gelation temperature of the stock solution. 3. In addition to the cold air for fluidizing the fluidized bed, cold air for cooling the spray liquid is further introduced from the lower part of the apparatus.
Or the cooling granulation method described in 2. 4. The fine powder is introduced into the device from the outside so that the fine powder concentration on the wall surface of the device is high.
The cooling granulation method according to any one of 3 above. 5. A cooling granulation chamber, a spray atomizing means installed in the upper part of the cooling granulation chamber, a hot air introducing means for introducing hot air to the peripheral portion of the spray atomizing means, and the cooling. A cooling granulation apparatus, comprising: a fluidized bed formed in the lower part of the granulation chamber, the fluidized bed fluidizing fine powder with cold air. 6. The cooling granulation apparatus according to claim 5, further comprising a cold air introduction unit provided in the lower part of the cooling granulation chamber, in addition to the cold air for fluidizing the fine powder. 7. The cooling granulation according to claim 5, further comprising a fine powder introducing means for introducing the fine powder into the cooling granulation chamber from the outside so that the fine powder concentration in the wall surface of the cooling granulation chamber becomes high. apparatus. 8. A coarse classification means for blowing away fine powder of the fluidized bed by increasing the fluidizing air velocity of the fluidized bed formed in the lower part of the cooling granulation chamber to leave fine particles having a larger particle size than the fine powder. The cooling granulating apparatus according to any one of claims 5 to 7, further comprising a drying unit that dries the fine particles remaining after being roughly classified by the coarse classifying unit with hot air. 9. The cooling granulating apparatus according to claim 5, further comprising a circulation means for circulating and using exhaust gas from the upper portion or the side portion of the apparatus.