JP2000354751A - High speed stirring method and high speed stirring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the boiling of a liquid due to heat friction at the time of stirring when the liquid is treated by using a high speed stirrer suitable for micronizing the liquid. SOLUTION: A circulating passage 12 is formed between a discharge port 11a of the high speed stirrer 1 for stirring raw materials supplied from raw material vessels 6, 7 and one side of a raw material supply port 2b through a switching valve 17, a cushion tank 13 having a larger capacity than that of a stirring tank 2, and a cooler 15 are provided in series in the circulating passage 12 when the liquid to be treated is stirred in the tank 2, the liquid is allowed to flow into the passage 12 and cooled just before its boiling caused by the frictional heat, then returned again to the tank 2 and stirred. This process is repeated to accumulate the stirring time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-speed stirring technology for emulsifying a liquid in a solvent into fine particles having a diameter of about 1 to 3 .mu.m or less than a micron in a short time, and is used for manufacturing pharmaceuticals, cosmetics and the like.

[0002]

2. Description of the Related Art An example of the above high-speed stirring apparatus is described in Japanese Patent Application Laid-Open No. 9-75698 filed by the present applicant. In this conventional apparatus, the stirring body is driven at a peripheral speed of 25 m /
When the stirring body is rotated at such a high speed, the raw material contained in the liquid to be treated is atomized in a very short time, but the liquid to be treated is
The temperature rises due to frictional heat generated by friction with the stirrer, which makes it easier to boil. If boiling occurs, stirring becomes impossible. Therefore, a water chamber is provided around the stirring tank and cooling water is circulated for cooling. However, in order to make the particles in the liquid to be treated finer,
If the peripheral speed of the stirrer is made higher, for example, 50 m / sec or more in order to shorten the stirring time, the cooling power from the water chamber is insufficient, so that the boiling cannot be suppressed.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a stirring means which does not cause boiling even if the peripheral speed of the stirring body is extremely increased.

[0004]

According to the present invention, there is provided an electronic apparatus comprising:
And 2 are solved. Among these, the means of claim 1 is to provide a stirrer having a diameter slightly smaller than the inner diameter of the stirrer in a cylindrical stirrer, to supply a small amount of the liquid to be stirred into the stirrer, and to rotate the stirrer at a high speed. In the high-speed stirring method in which the liquid to be treated is stirred while being raised in a thin film cylindrical shape, a circulation passage in which a liquid feed pump and a cooler are connected in series between a discharge port and a supply port of the liquid to be treated in the stirring tank. Is established,
A high-speed stirring method characterized in that the liquid to be treated is transferred to a circulation passage and cooled immediately before the liquid to be treated boils due to frictional heat generated by stirring, and the circulation of returning the cooled liquid to the stirring tank is repeated. It is.

According to this means, the liquid to be treated is controlled so as to flow for a required time in the stirring tank by adjusting the amount of liquid to be sent, and is stirred for a very short time until just before boiling. And the mixture is forcibly cooled by a cooler. After cooling, the mixture is returned to the stirring tank and stirred. By repeating this action, stirring with atomization without boiling is performed.

A second aspect of the present invention is that a stirrer having a diameter slightly smaller than the inner diameter of the stirrer is provided concentrically in a cylindrical stirrer, and a small amount of the liquid to be treated is supplied to the stirrer to form the stirrer. In a high-speed stirring device that rotates at a high speed and stirs the liquid to be treated while rising it into a thin film cylinder, a cushion tank, a liquid feed pump, and a cooler are provided between a discharge port and a supply port of the liquid to be treated in the stirring tank. A high-speed stirring apparatus characterized in that a circulation path is provided in series, and a valve for taking out a liquid to be treated is provided in the circulation path.

According to this means, the liquid to be treated is stirred for a very short time until immediately before boiling, then discharged from the stirring tank to the circulation passage, gradually cooled while accumulating in the cushion tank, and further forcibly cooled by the cooler. After cooling, the mixture is returned to the stirring tank and stirred. By repeating this action, stirring with atomization without boiling is performed.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, reference numeral 1 denotes a high-speed stirrer provided with a cylindrical stirring tank 2 and a stirrer 3. The stirrer 3 has, for example, the structure shown in FIG. 2 and is driven at a high speed by a motor 4 and a drive shaft 5. . Supply ports 2a, 2b at the bottom of the stirring tank 2
, Raw material tanks 6,7 are connected by supply pipes 8,9,
Liquid feed pumps 8a and 9a are interposed in the supply pipes 8 and 9, respectively. A ring plate-shaped dam plate 10 and an upper chamber 11 are stacked on the upper part of the stirring tank 2 and discharged into the upper chamber 11. An outlet 11a is provided.

[0009] Between the discharge port 11a and the supply port 2b,
A circulation passage 12 for the liquid to be treated is provided. The circulation passage 12 is provided with a cushion tank 13, a liquid feed pump 14, a cooler 15, a three-way valve type take-off valve 16 and a switching valve 17, and these are provided. Each element is provided with a passage 12a, 12b, 1
2c, connected by a supply pipe 9, and a take-out valve 16 provided on the downstream side is connected to a product container 18. The volume of the cushion tank 13 is set to be several times the amount of the liquid to be treated that becomes a thin-film cylindrical shape in the stirring tank 2.

The cooler 15 is of a type in which, for example, a coil-shaped inner tube 15a through which a liquid to be treated passes is sealed in a case 15b and a cooling medium flows through the case 15b. 19, the passages 19a, 19
circulate through b. Further, thermometers 20, 21, 22 are provided for measuring the temperature of the liquid to be treated in each part,
A flow meter 23 for measuring the circulation flow rate is also provided. Cooler 1
5 can be made different depending on the physical properties of the liquid to be treated.
A passage for the liquid to be treated may be used on the 5b side, and other different types can be used.

FIG. 2 is a detailed view showing an example of the high-speed stirrer 1. The stirring tank 1 is surrounded by a water-cooling chamber 25 and water pipes 25 a, 2.
It is cooled by the cooling water passing through 5b. Stirring body 3
Corresponds to Japanese Patent Application No. 10-165035 previously filed by the present applicant.
No. 26a has the same configuration as that described in
Has a cylindrical portion 26, an arm 27, and a boss 28,
The boss 28 is connected to the drive shaft 5. The dam plate 10 and the upper chamber 11 are attached to the upper part of the stirring chamber 2, and a discharge port 11a is provided continuously. A water cooling chamber 29 is also provided in the upper chamber 11, and cooling water flows through the water pipes 29a and 29b. The size of the stirrer can be arbitrarily set, but for small-quantity production, a stirrer with an inner diameter of 80 mm and an outer diameter of the stirrer 3 of 76 mm is used, for example. The stirrer 3 is not limited to the above-described one, and may be of any type such as a wire type in which a large number of wires are radially provided, or a gear type in which irregularities are provided on the outer peripheral surface. Speed has the greatest effect on atomization.

In this stirring apparatus 1, when the stirring body 3 is driven at a peripheral speed of 40 to 50 m / sec or higher while supplying water and raw materials mixed with an emulsifier as supply liquids from the supply pipes 8 and 9, The liquid to be treated L is rotated by receiving the rotational force from the stirring body 3, is pressed against the inner surface of the stirring tank 2 by centrifugal force, rises, and passes through the small hole 26 a from the inner peripheral side to the outer peripheral side of the cylindrical portion 26. The flow and the position of the inner peripheral surface of the liquid to be treated are regulated by the inner peripheral surface of the weir plate 10, and the entire liquid becomes a thin film cylindrical shape. Due to this movement, the liquid to be treated L rubs against the inner peripheral surface of the stirring tank 2 and the inner and outer peripheral surfaces of the stirring body 3 and also rubs against the inner surface of the small hole 26a. The temperature rises to about the boiling point of water. In the stirring tank 2, the amount of the liquid to be treated, which is regulated in a cylindrical shape by the weir plate 10, is 250 ml. As the supply of the liquid to be processed is continued, the heated portion enters the upper chamber 11 over the weir plate 10 and continues to rotate along its inner surface by inertia to form a cylindrical shape, which is discharged from the discharge port 11a. The discharged liquid to be processed enters the circulation path 12 in FIG. 1 and is temporarily accumulated in the cushion tank 13 and naturally cooled. When the liquid to be treated is substantially filled in the cushion tank 13, the liquid feed pumps 8a,
When the supply of the raw material is stopped by stopping 9a and the switching valve 17 is switched to the circulation path 12 to operate the liquid feed pump 14, the liquid to be treated in the cushion tank 13 is sent to the cooler 15, where it is sent. Forcibly cooled to a temperature of, for example, 10 ° C.
Further, it passes through the passage 12c and the supply pipe 9, returns to the stirring tank 2, and receives the stirring action again. In other words, the liquid to be treated is repeatedly subjected to high-speed stirring for a short time and cooling for a longer time. If the total stirring time is 2 to 5 minutes, the raw material becomes fine particles having a particle diameter of about 1 μm. Therefore, if the cumulative time for obtaining the desired particle diameter is determined by an experiment, the liquid to be treated may be circulated through the circulation path 12 until the cumulative time is reached.

The time required for 250 ml of the liquid to be treated in the stirring tank 2 to reach the temperature immediately before boiling and discharged is 10 seconds, the capacity of the cushion tank 13 is 1000 ml, the inner pipe 15a of the cooler 15 and other parts are provided. 250 ml of passage volume
In this case, the total volume of the circulation portion is 1500 ml, which is six times the volume of the stirring tank 2.
Circulates once every 0 seconds or 1 minute.

If the total time for stirring is 3 minutes, that is, 180 seconds, stirring for 10 seconds is 1
Since it is necessary to carry out eight times, and one circulation requires one minute as described above, stirring and cooling may be performed alternately and continuously for 18 minutes. Of liquid can be processed, which is about three times as much as 4.5 liters of liquid per hour. When the cooling capacity is low, the stirring is interrupted to lower the liquid temperature while the cooling from the water cooling chamber 25 and the natural cooling in the cushion tank 13 are performed, and then the stirring is performed. What should I do?

The above operation may be performed by automatically controlling the motor 4, the liquid feed pump 14, and the cooling device 19 based on the detection values of the thermometers 20, 21, 22. After a predetermined stirring time has elapsed, the liquid to be treated is taken out from the valve 16 and transferred to the product container 18, and the process returns to the initial operation of supplying the raw materials from the raw material containers 6, 7.

[0016] Having described the example of continuously stirring the liquid to be treated, instead of the passage 12a, the lower passage 12a ₁ which communicates the lower the cushion tank 13 of the stirring tank 2 is provided,
The liquid to be treated and stirred with 1 batch fed into the stirring tank 2, may be a batch operation so as to move from the lower passage 12a ₁ to cushion tank 13 each time the stirring once ends.

The cushion tank 13 can be omitted if the volumes of the passages 12a, 12b, 12c, the inner pipe 15a and the like are increased.

[0018]

As is clear from the above description, according to the first aspect of the present invention, a high-speed stirring method suitable for atomizing liquid is used for stirring the liquid to be treated, and the heat generated by the high-speed stirring method is used. Since cooling is performed while circulating through a circulation passage having a cooler, stirring can be performed continuously, and there is an effect that a large amount of stirring can be performed by a small-capacity stirring means.

According to a second aspect of the present invention, there is provided an apparatus suitable for carrying out the stirring method of the first aspect, wherein a large-capacity cushion is provided on the inlet side of the circulation passage, so that the agitation can be performed continuously. The amount of liquid can be increased, and there is an effect that a large amount of liquid can be processed with a small capacity stirrer.

[Brief description of the drawings]

FIG. 1 is a system flow diagram according to an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of a high-speed stirrer used for carrying out the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 High-speed stirrer 2 Stirring tank 3 Stirrer 6,7 Raw material tank 10 Weir plate 12 Circulation passage 13 Cushion tank 15 Cooler 16 Take-out valve 18 Product container

Claims (2)

[Claims] An agitator having a diameter slightly smaller than the inner diameter of the agitator is provided concentrically in a cylindrical agitator, a small amount of the liquid to be treated is supplied to the agitator, and the agitator is rotated at a high speed. In the high-speed stirring method of stirring the processing liquid while rising in a thin film cylindrical shape, between the discharge port and the supply port of the liquid to be processed in the stirring tank,
A circulation path in which a liquid feed pump and a cooler are arranged in series is provided, and the liquid to be treated is transferred to the circulation path and cooled immediately before the liquid to be boiled by frictional heat generated by stirring, and the cooled liquid to be treated is again stirred in the stirring tank. A high-speed stirring method characterized by repeating the circulation returning to the atmosphere. 2. A stirrer having a diameter slightly smaller than the inner diameter of the stirring tank is provided concentrically in a cylindrical stirring tank, a small amount of the liquid to be treated is supplied to the stirring tank, and the stirring body is rotated at a high speed. In a high-speed stirring device that stirs the processing liquid while rising it into a thin film cylindrical shape, between the discharge port and the supply port of the liquid to be processed in the stirring tank,
A high-speed stirring device comprising: a circulation passage in which a cushion tank, a liquid feed pump, and a cooler are arranged in series, and a discharge valve for a liquid to be treated is provided in the circulation passage.