JPH0975698A - Method and apparatus for high seed agitation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an agitated material which has a small particle size and good quality in an apparatus in which two kinds of liquid, liquid and powder, and others are mixed and agitated. SOLUTION: A blade 6 which extends close to the inner surface of a container 2 and rotates at a high speed is installed in the container 2, and the inflow pipe 10 and outflow pipe of treatment liquid L are connected. When the liquid L is introduced from the pipe 10 little by little in comparison with the volume of the container 2 into the container 2 and the blade 6 is rotated at a high speed, the liquid L is rotated to make a hollow thin film by centrifugal force and agitated at a high speed at the outer end of the blade 6 to flow out from the pipe 16 beyond a baffle board 18. When badge treatment is conducted, the pipe 16 is closed, and the liquid L is discharged from a lower discharge pipe 17 after agitation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stirring method and a stirring device for treating a mixture of a liquid and a liquid or a mixture of a liquid and a powder as a treatment liquid to highly finely disperse and emulsify the treatment liquid.

[0002]

2. Description of the Related Art A conventional stirring device is provided with a stirring tool, namely, a blade, which rotates at its central portion in a stirring container, and the processing liquid is stirred and finely divided by the blade. FIG.
10 (a) and 10 (b) show an example of a conventional technique. In FIG. 10 (a), a small-diameter blade c is provided on a shaft b extending into the container a, and the shaft b is rotated to pass the treatment liquid d. Stirring is to stir and disperse the treatment liquid d by the blades c and to cause upward and downward circulation in the direction of arrow e to stir, and to prevent the treatment liquid d from idling. A rib-shaped stator f is provided on the inner surface of the. In this device, the diameter D ₁ of the blade c is considerably smaller than the inner diameter D of the container a and is generally one fifth or less of D. In the figure, a ₁ is a jacket for circulating a heat medium for heating or cooling.

[0003] In FIG. 10 (b), the inclined shaped blade c ₁ is used as a blade, a stator f surrounding the vane c ₁ is held by the fixture g. This device is Japanese Patent Publication No. 6-7913.
The shaft b is rotated at a high speed so that the blade b
Is driven at a peripheral speed of about 15 m / sec to positively generate cavitation on the back surface of the blade b in addition to the shearing action to promote atomization.
Circulates as indicated by arrow e ₁ .

The above-mentioned conventional technique has the following drawbacks.

Treatment liquid d which is affected by the blades c and c _1.
Is limited to the vicinity of the blade c, c _1, arrows e, blade c by circulation of e _1, although the action of c ₁ is equalized, the circulation number to process the entire treatment liquid d The processing time is long.

When the treatment liquid d is rotated together with the blade, the stirring action is reduced, so that it is necessary to provide the stators f and f ₁ as shown in FIGS.

When the blades c and c ₁ are rotated at high speed in order to give high energy to the treatment liquid d, a slip phenomenon accompanied by cavitation occurs at a certain number of rotations, especially when a high viscosity treatment liquid is stirred. In addition, the stirring action is extremely reduced due to the slip phenomenon.

At the time of work, a heat medium is circulated in the jacket a ₁ and the treatment liquid is often stirred or filled and discharged while being heated or cooled. The temperature distribution becomes uneven and it is difficult to stir the blades c and c _{1 at} a uniform temperature.

In order to improve this condition, an auxiliary device such as an agitator or a scraper is used to generate the whole flow, but not only the mechanism becomes complicated, but it is difficult to obtain a sufficient result.

Stirring for higher-order micronization, dispersion, and emulsification is difficult to solve depending on the shape of the blade and the addition of the above-mentioned auxiliary equipment. On the contrary, the amount attached to each part increases and the yield decreases. Also, if the positions of the blades c and c ₁ are too close to the bottom, the circulation of the entire processing solution will deteriorate, so the position is set to an appropriate height, but if this is done, the minimum processing amount cannot be reduced and profitability is improved. Becomes worse. In addition, if an agitator or scraper is added, the structure becomes complicated and the washability also deteriorates.

[0011]

SUMMARY OF THE INVENTION The present invention provides the following
The task is to solve the difficulties of.

[0012]

A method for solving the above-mentioned problems is, as described in claim 1, that a treatment liquid is contained in a container, and a stirring tool is rotated in the treatment liquid to obtain the treatment liquid. In the stirring method for stirring, a stirring tool having an end reaching near the inner peripheral surface of the container is rotated at high speed in the processing liquid, and the processing liquid is rotated by the rotation of the stirring tool to centrifuge the processing liquid. It is characterized in that it is agitated at the end of the agitator while being pressed against the inner surface and rotated in the form of a hollow thin film.

According to this means, the treatment liquid is rotated at a high speed by receiving the energy of the agitator, and is pressed by the centrifugal force to the inner surface of the container to form a hollow thin film and is rotated. It is slower than the rotation speed of the tool. For this reason, the treatment liquid on the rotating surface of the stirring tool is always subjected to the stirring effect by the end of the stirring tool and also the stirring operation accompanying the rotation of the flow occurs to be finely divided.

An apparatus for implementing the above means is
As described in claim 2, in a stirring device having a container having a circular cross section and capable of containing a processing liquid, a rotating shaft provided at the center of the container, and a stirring tool attached to the rotating shaft, It is characterized in that it is provided with a stirring tool having a radius reaching the vicinity of the peripheral surface and a drive source for driving the stirring tool at a high speed at a peripheral speed of 20 m / sec or more.

According to this means, since the end of the agitator reaches the vicinity of the inner surface of the container, a small amount of the processing liquid is supplied into the container to rotate the agitator at a high speed. If
The treatment liquid becomes a hollow thin film along the inner surface of the container and is agitated due to a speed difference between the treatment liquid and the agitator, and is agitated by the rotation of the flow to be finely divided.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, 1 is a high-speed stirring apparatus of the present invention, 2 is a container, 3 is a lid of the container 2, and a bearing 4 is fixed to the lid 3 to support a drive shaft 5. The lower end of the shaft 5 blades 6 as mixing tool is fixed, the outer end of the vane 6 and protrusion ₆₁ for improving the stirring action is attached toward the vertical direction, the outside of the blade A slight gap S is provided between the end and the inner surface of the container 2. A motor 7 is fixed to a stationary part (not shown), and a motor shaft 7 ₁ is connected to the shaft 5.

An inflow pipe 10 from a tank 9 for processing liquid is connected to the bottom 8 of the container 2 via a pump 10 ₁ and a valve 10 _2, and another tank is connected to the valve 10 ₃ . On the lid 3, the additive tanks 11 and 12 are connected to the valves 13 ₁ ,
A vacuum pipe 15 penetrating through pipes 13 and 14 extending through 14 ₁ and communicating with a vacuum source via a valve 15 _1.
Penetrates and can be stirred even in vacuum. An outflow pipe 16 for the processed liquid is connected to an upper side surface of the container 2, and a lower discharge pipe 17 is connected to a lower side surface thereof. 1
6 ₁ and 17 ₁ are valves. The outflow pipe 16 is used for the outflow of the processing liquid during the continuous processing, and the lower discharge pipe 17 is used for the outflow of the processing liquid during the badge processing or the discharge of the cleaning liquid after cleaning.

Although the inner surface of the container 2 is a cylindrical surface, the outflow pipe 1
At a position below 6 is provided a flange-shaped flow blocking ring 18 which projects inward of the container 2. Further, jackets 19 and 20 are provided on the outer surface of the container 2 so that a heat medium for heating or cooling flows. Reference numeral 21 denotes a particle size measuring device for the processing liquid, which is provided in the outflow pipe 16, and the state of miniaturization can be observed.

When the processing liquid L is put in the container 2 up to the vicinity of the blade 6 and the motor 7 is energized to rotate the blade 6 at a high speed, the processing liquid L is hit by the blade and receives the energy of the blade to rotate. Then, it is pressed against the inner surface of the container 2 by the centrifugal force to increase the pressure, and becomes a hollow thin film and rotates. The rotation of the treatment liquid L occurs not only in the portion in contact with the blade 6, but also in the portion separated from the blade 6 as the treatment liquid L rotated by the blade 6 moves, and air exists in the container 2. At this time, the rotation is transmitted to the treatment liquid L via the rotation of the air, and the treatment liquid L is rotated.

The rotation speed of the blade 6 is higher than the rotation speed of the processing liquid, and the gap S between the container 2 and the blade 6 is small.
The treatment liquid L existing in the vicinity of the end of is completely stirred by the blades 6 and highly highly refined, dispersed, mixed and emulsified. The processing liquid inside and outside the rotating surface of the blade 6 is also subjected to the mixing action due to the speed difference during the rotational movement due to the inertia of the processing liquid itself, the generation of a vortex, and the like.

The treatment liquid L in the form of a hollow body is used for the flow blocking ring 1.
Although the stirring is performed while the rising is restricted by 8, the stirring is surely performed by the tip portion of the blade 6 while rising along the inner surface of the container 2, so that the stirring is sufficiently performed in a short time. After passing through the flow blocking ring 18, the rotation and pressure are maintained, and the pressure causes the outflow pipe 16 to flow out.

In this operation, the rising speed of the processing liquid L rising along the inner surface of the container 2 is proportional to the inflow speed from the inflow pipe 10, and the liquid amount passing over the flow blocking ring 18 becomes the inflow liquid amount. equal. Therefore, the inflow speed can be controlled by the pump 10 ₁ or the valve 10 ₂ to adjust the rising speed or the residence time, and the stirring energy input from the blades 6 to the processing liquid L can be adjusted by this. It can be easily agitated.

FIG. 2 shows data on the stirring action by the conventional apparatus and the apparatus of the present invention. The vertical axis represents the average particle size (μm) of the processing liquid, and the horizontal axis represents the processing time (minutes). Water: paraffin was mixed at a ratio of 4: 1 and 1% or less of an interfacial lubricant was added thereto. In the figure, the A group is based on a conventional apparatus having a different type, and the B group and the C group are based on the apparatus of the present invention, but the B group is operated at substantially the same peripheral speed as the A group. Line A ₁ ~
In the device showing the data of C ₄ , the blade shape, the amount of processing liquid, etc. are slightly different, but the inner diameter of the container is 156 mm for each of A, B, and C groups, and the blade diameter is 38 mm for the A group. Which is 152 mm in the B and C groups. Therefore, the gap S between the inner surface of the container 2 and the end of the blade 6 in the B and C groups is 2 mm.

The speed fill in each line A ₁ -C ₄ represents the peripheral velocity of the blade, at a peripheral speed of A ₁ 13.1m / sec, in A ₂ 1
It is 4.9 m / sec. Group B shows data obtained while substantially matching the conventional apparatus and the peripheral speed of the blade with the blade of the same structure as the group C, the peripheral speed of the blades B ₁ of 1
3.35 m / sec, B ₂ , B ₃ , and B ₄ are 14.7 m / sec. These peripheral velocities are approximately maximum values in the conventional device.

On the other hand, in the apparatus of the present invention, the peripheral speed can be increased as much as possible because the hollow thin film liquid is agitated, and in the C group, C ₁ is 27.45 m / s.
ec, C ₂ is 28.6 m / sec, C ₃ is 37.9 m / sec, C
₄ is 42.6 m / sec. The mixed state of A _{1 to} C ₄ at the time of departure is the same.

Then, in order to describe in detail the degree of atomization of the paraffin particles and the required time, in the group A, 11-12.
It takes 15 minutes to reach 5 μm, and 7-1 for Group B
It takes 6 minutes to reach 2 μm and 15 minutes to reach 5 μm.

On the other hand, in the C group, C 3 is 3 minutes, C ₁ is 3 minutes, C ₂ is 1.7 minutes, C ₃ is 0.5 minutes, and C ₄ is 0.2 minutes. It becomes 5 μm. Also, C ₃ is 1.
2 minutes for 7 μm, 1 for C ₄ 1.5 μm
It only takes minutes.

As described above, in comparison with the A group by the conventional device and the B group driven at the same peripheral speed as this, C
The degree and time of atomization of the group is remarkably excellent,
The reason is understood to be the result of agitating the entire hollow thin film-shaped treatment liquid L at the outer end portion of the high-speed blade at high speed, and according to the experiment, this effect was obtained when the peripheral speed of the blade was around 20 m / sec. Occurs and the effect is remarkable at 30 m / sec or more. Since the treatment liquid L is in the form of a thin film during this stirring,
The heating or cooling from the jackets 19, 20 provides a fast and uniform heat transfer.

Although it takes less time to atomize the group C, the working radius or the peripheral speed of the impeller is larger than that of the groups A and B, so that a motor that rotates at high torque and high rotation speed is required, and the input amount Must also be large. Further, as is clear from the lines C _{1 to} C _{4 in the} group C, the larger the peripheral velocity is, the smaller the particle diameter is. Therefore, by changing the peripheral velocity, the particles having a desired particle diameter can be obtained.

The particle size distribution in the processing liquid changes depending on the gap S between the inner surface of the container 2 and the blade 6. FIG. 4 shows the change in particle size distribution when the gap S is changed. The middle one is the curve b. The larger one has the distribution shown by curve C. Therefore, by adjusting the peripheral speed of the blades 6 and the clearance S, it is possible to obtain an arbitrary particle size and particle size distribution, and it is possible to easily perform high-level atomization and uniform particle size processing.

Although the container 2 in the above embodiment has a simple cylindrical shape, a multi-stage cylinder 22 is formed as shown in FIG. 3, and the position of the blade 6 is adjusted according to the desired particle size distribution or the viscosity of the processing liquid. May be changed.

Further, a large number of protrusions 23 are provided on the inner surface of the container at positions outside the blades 6 to generate resistance to the flow in the circumferential direction and the axial direction, thereby increasing the number of stirring substantially by the blades. You can also In group C, if the inner diameter of the container 2 and the outer diameter of the blades 6 are larger than the above numerical values, the same action occurs if the gap S is small.

Although the inner surface of the container 2 is a cylindrical surface, the retention time of the processing liquid can be changed by making the inner surface a tapered surface as shown in FIGS. FIG.
The container 2 is provided with a large-diameter tapered surface 25 on the upper portion, and the container 2 in FIG. 6 is provided with a small-diameter tapered surface 26 on the upper portion.

In FIG. 5, the processing liquid that flows in from the inflow pipe 10 and is rotated by the blades 6 easily flows toward the large diameter side by the centrifugal force, and therefore flows rapidly in the direction of the arrow 27. Therefore, the staying time in the container 2 is short and the degree of stirring is low. On the other hand, in the container 2 of FIG. 6, the blades 6 are urged to flow toward the large diameter side of the tapered surface 26, but because they are blocked by the bottom surface, they are reversed as shown by arrow 28 and then flow out in the direction of arrow 29. . The reversal of the flow at this time is not limited to once, and the stirring is performed by the blade while repeating the reversal, so that the stirring degree becomes extremely high.

Instead of the blades 6, the stirring members shown in FIGS. 7 and 8 can be used. FIG. 7 shows a gear type blade 30.
The blade 30 is provided with a disk 30 ₂ , a ring portion 30 ₃ , and a large number of teeth 30 ₄ centering on a boss 30 ₁ , and several holes 30 ₅ are provided in the disk 30 ₂ .

Since the gear type blade 31 has a structure substantially the same as that of the transmission gear and is made by a machine tool, it can be made with extremely high precision and in good balance, and even if the gap S with the inner surface of the container is made small, There is no risk of contact with the inner surface or vibration. Furthermore, since a large number of teeth 30 ₄ can be provided, it is possible to provide a high stirring property.

FIG. 8 shows the brush type blade 31, and the blade 3
In No. ₁ , a large number of wires 31 ₂ are radially and axially fixed to the boss 31 ₁ in multiple layers. Since a large number of wires 31 ₁ pass through the treatment liquid for each rotation, the blade 31 has a large shearing action and stirring action on the treatment liquid.

The apparatus shown in FIG. 9 is a multi-stage apparatus for further improving the performance of the apparatus shown in FIGS. The inside of the container 2 is divided into three stirring chambers 34 ₁ , 3 by two partition walls 33.
It is divided into 4 ₂ and 34 ₃ , and the respective stirring chambers are communicated with each other by the central holes 33 ₁ and 33 ₂ of the partition wall 33. Two gear type blades 30 are fixed to the drive shaft 5 for each of the stirring chambers 34 _{1 to} 34 ₃ .

The processing liquid supplied from the inflow pipe 10 enters the stirring chamber 34 ₁ and is stirred by receiving the rotational force from the teeth 30 ₄ of the gear type blade 30, and then as indicated by a continuous arrow 35. Center hole 33 ₁ , stirring chamber 34 ₂ , center hole 33 ₂ , stirring chamber 3
After passing through 4 ₃ and being stirred by the gear type blade 30, it is taken out from the outflow pipe 16.

During this time, the treatment liquid is sufficiently mixed by being hit by the teeth 30 ₄ while being pressed against the inner surface of the container 2 by centrifugal force or subjected to a shearing action or the like.

In each of the above-mentioned embodiments, as the agitator attached to the drive shaft 5, the blade 6 and the gear type blade 3 are used.
It is needless to say that either 0 or the brush type blade 31 can be selected and used, and various stirring tools having the same effect as these can be used.

Further, in each of the above-described embodiments, the drive shaft 5 is shown as a vertical type which is oriented in the vertical direction, but a horizontal type can be operated without trouble.

[0043]

As is apparent from the above description, according to the invention of claim 1, the particle size of fine particles can be reduced to a fraction or less as compared with the prior art, and the processing time can be several times. Since it can be reduced to one-tenth or less, an excellent effect that cannot be foreseen from the prior art is produced, and there is an advantage that a good quality agitated product can be efficiently obtained.

Further, since the treatment liquid is held in a thin film on the inner surface of the container, there is an advantage that the heat transfer can be performed quickly and uniformly when heating or cooling from the outer surface of the container.

Next, according to the invention of claim 2, since no moving parts other than the stirring tool and the shaft are used in the container, the operation of claim 1 can be performed with an extremely simple structure. In addition, the part where the processing liquid adheres after the work is
Since there is nothing other than a container, a stirrer, and a shaft, there is an advantage that the amount of waste in cleaning is small, the yield of materials is good, and cleaning work is easy.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of an embodiment of the present invention.

FIG. 2 is a diagram showing the relationship between stirring time and particle size.

FIG. 3 is a partial view showing another example of the container.

FIG. 4 is a diagram showing a relationship between a space between a container and a blade and a particle size distribution.

FIG. 5 is a schematic diagram of an embodiment of a tapered container.

FIG. 6 is a schematic representation of another embodiment of a tapered container.

FIG. 7 is a front view of a gear type blade.

FIG. 8 is a front view of a brush type blade.

FIG. 9 is a vertical cross-sectional view of a multistage embodiment.

FIG. 10 is a vertical sectional view of a conventional device.

[Explanation of symbols]

 2 Container 3 Lid 5 Shaft 6 Blade L Processing Liquid S Gap 30 Gear Type Blade 31 Brush Type Blade 33 Partition Wall

Claims (2)

[Claims] 1. A stirring method in which a treatment liquid is contained in a container and a stirring tool is rotated in the treatment liquid to stir the treatment liquid,
An agitator having an end reaching near the inner peripheral surface of the container is rotated at high speed in the treatment liquid, and the treatment liquid is rotated by the rotation of the agitator so that the treatment liquid is pressed against the inner surface of the container by a centrifugal force and is hollow. 2. A high-speed stirring method characterized by stirring at the end of the stirring tool while rotating in a thin film form. 2. A stirrer having a container having a circular cross section and capable of containing a treatment liquid, a rotary shaft provided at the center of the container, and a stirrer attached to the rotary shaft, in the vicinity of the inner peripheral surface of the container. A stirrer with a radius of up to 2 and a peripheral speed of 2
A high-speed stirring device comprising a drive source that drives at a high speed of 0 m / sec or more.