JPH0643496B2 - Vertical twin-screw agitator - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a batch type polymerization apparatus, which is suitable for vertical twin-screw agitation suitable for treating a polymer that changes from a liquid phase to a solid phase. It relates to the device.

[Conventional technology]

Fig. 4 shows a conventional stirring tank. The figure shows a double-helical ribbon blade type used to stir a high-viscosity liquid up to several thousand poises. In this case, the higher the viscosity of the liquid, the worse the mixed state unless the entire range of the casting liquid is stirred. Therefore, the double helical type is effective as the stirring blade. However, this stirring blade is used when processing in a liquid phase state, and in the case of a processing liquid that undergoes a phase change from a liquid phase to a solid phase, adhesion of the polymer becomes a problem because of the rotating shaft.
Examples of devices related to this type include, for example, Japanese Utility Model Publication No. 53-50939 and Japanese Utility Model Publication No. 43-29267.

[Problems to be solved by the invention]

In the above-mentioned conventional technology, no consideration is given to the inclination angle θ of the stirring blade, and since the inclination angle θ of the stirring blade is small, the solid-phased processed product is lifted by the rotation of the stirring blade and deposited on the upper part, There was a problem that cavities were generated and sufficient stirring and mixing processing could not be performed.

An object of the present invention is to provide a vertical twin-screw agitator capable of handling a processing liquid (polymer) that undergoes a phase change from a liquid phase to a solid phase and capable of obtaining sufficient mixing in a tank. is there.

[Means for solving problems]

The above object is to provide two rotating ear shafts in a vertically installed cylindrical container, and to attach the spiral twisting blades formed of round bars having mutually different twisting directions to the rotating ear shafts. Are mutually held within the rotation region of the opposite spiral twisted blades and are held at a rotating interval, and the inclination angle θ of the spiral twisted blades is set to 30 ° to 85 °.

[Action]

By setting the inclination angle θ of the spiral twisting blade to an angle that is equal to or greater than the repose angle of the processing liquid during the phase change, the amount of lifting of the processing liquid can be reduced, and the mixing effect, which is the processing purpose during the phase change, can be reduced. Good mixing is achieved due to less lifting of the. Further, since the stirring blade is formed of the rod-shaped member, the treatment liquid does not adhere to the stirring blade.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. In the figure, reference numeral 1 denotes a container body of the processing apparatus, which is a vertically long cylindrical container having a cross section shown in FIG. Generally, body 1
Is covered with a jacket 7, a heating coil or a heater (not shown). The main body 1 is provided with a treatment liquid inlet nozzle 4 and an outlet nozzle 5. Two
Is a rotating ear shaft attached to the container body 1, and the rotating ear shaft 2 is connected to a drive device (not shown). The rotating shaft 2 includes an upper horizontal bar 8, a lower horizontal bar 9, and an intermediate horizontal bar 6.
And a stirring blade formed by the spiral torsion blade 3 is attached. The spiral twisting blades 3 have a predetermined inclination angle (inclination of θ), and each has a different twisting direction, and is twisted in a direction to scrape up the processing liquid in the container body 1 upward. The rotation directions are different from each other and rotate outward from the center. The spiral twisting blades 3 rotate while entering each other's spiral twisting blades 3 and scrape the entire inner wall of the container body 1 to feed the processing liquid upward, thereby causing the liquid to flow vertically. When the solid phase changes, the treatment liquid is mixed due to the action of the intermediate horizontal bar 6. Since these stirring actions are performed by the rod-shaped structure, it is possible to reduce the amount of the processing liquid adhering to the stirring blades, and to lift the treatment liquid to the upper portion of the container body. Therefore, since sufficient mixing can be obtained, a product of stable quality can be obtained. In order to explain the lifting effect when changing the inclination angle, the spiral torsion blade diameter is about 290 mm, the length is about 350 mm,
An agitating blade having a member diameter of 22 mm, a vinyl chloride particle as a simulated liquid, and an agitating blade having different inclination angles θ of the spiral twisting blade 3 were manufactured, and the lifting amount was measured. An example of the experimental results is shown in FIG. With the same amount of extension and the same number of rotations, the result is that the amount of lifting is smaller when the inclination θ of the spiral torsion blade is larger.

The setting of the inclination angle θ of the spiral twisting blade 3 is an important problem in stirring and mixing the processing liquid changing from the liquid phase to the solid phase. That is, while sliding the treatment liquid on the spiral twisting blade 3,
Move it to the top and mix it so that there are no cavities in the bottom,
In order to obtain a circulating flow in the tank, a tilt angle θ larger than the repose angle of the processed material is required. Generally, the angle of repose of the powdery polymer is 30 ° or more, and if the inclination angle θ is larger than that, the treatment liquid slips on the spiral twisting blade 3 and the lift amount to the upper part is suppressed. Further, in the case of 90 °, the treatment liquid cannot be lifted up, and it is necessary to set the optimum inclination angle θ suitable for the polymer in order to move vertically and obtain sufficient mixing. Since the angle of repose differs depending on the type of polymer, the upper limit value of the inclination angle is set to 85 ° in order to set the inclination angle θ according to the selected polymer. As described above, when the inclination angle θ of the spiral twisting blade is set to an optimum value in the range of 30 ° to 85 °, the treatment liquid is circulated in the vertical direction while being lifted by an appropriate amount, the mixing at the time of phase change becomes good, and the treatment liquid is stirred. It also has the effect of preventing adhesion to the wings.

〔The invention's effect〕

According to the present invention, for a polymer that undergoes a phase change from a liquid phase to a solid phase, a good mixing effect can be obtained by scraping the entire surface, and the adhesion to the stirring shaft and the upper part of the stirring tank is eliminated, and the treatment liquid is solid-phased. Since all the things are mixed and there is no adhesion inside the main body, there is an effect that the entire amount can be dispensed and the quality of the product can be stabilized.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a vertical twin-screw agitator according to an embodiment of the present invention, FIG. 2 is a sectional view taken along line II-II of FIG. 1, and FIG. FIG. 4 is a longitudinal sectional view of a conventional liquid and powder processing apparatus, showing a characteristic example of the lifting amount in the case of the above. 1 ... Main body, 2 ... Rotating ear shaft, 3 ...
Spiral twisting blade, 4 ... Treatment liquid inlet nozzle, 5 ... Treatment liquid outlet nozzle, 6 ... Intermediate horizontal bar, 7 ... Jacket, 8
…… Upper horizontal bar, 9 …… Lower horizontal bar

Claims (4)

[Claims] 1. A vertically arranged cylindrical container is provided with two rotating ear shafts, and spiral helix blades having mutually different twist directions are attached to the circuit ear shafts, and the spiral helix blades are opposed to each other. A vertical twin-screw agitator, characterized in that the spiral twisting blade is held at a rotating interval while entering the rotation region of the spiral twisting blade, and the inclination angle θ of the spiral twisting blade is set to 30 ° to 85 °. 2. A vertical twin-screw agitator according to claim 1, wherein the spiral twisting blade is constituted by providing a plurality of intermediate horizontal bars between the spiral twisting blades. 3. A vertical twin-screw agitator according to claim 1 or 2, wherein the helical twisting blade is constituted by a rod-shaped member. 4. The spiral torsion blade according to claim 1, 2 or 3, wherein the spiral torsion blades corresponding to each other when viewed from the axial direction have a phase angle of 90 °. Vertical type twin-screw stirring device.