JPS605226A - Particulate material stirring apparatus - Google Patents

Abstract

PURPOSE:To rapidly and uniformly perform the stirring of a particulate material, by attaching disc shaped members to a plurality of rotary shafts, which is provided so as to pierce the side wall of a container in parallel, and to be alternately overlapped with each other while protruding a plurality of flat plate- shaped stiring blades to the outer periphery of each disc-shaped member. CONSTITUTION:Rotary shafts 3a, 3b are attached in parallel so as to pierce the both side walls of a container 1 while disc shaped member 6a, 6b, through which a heating or cooling medium is flowed, are alternately attached to the rotary shafts 3a, 3b to be arranged so as to partially overlap adjacent disc shaped members 6a, 6b. Flat plate shaped stirring blades 5a, 5b each having protruded pieces 7a, 7b at both end parts thereof are attached to the outer peripheries of the disc shaped members 6a, 6b so as to be directed towards the rotary shafts 3a, 3b while approaching the adjacent disc shaped members 6a, 6b at the overlapped part of the disc shaped members 6a, 6b. In addition, the lower part of the container 1 is partially constituted into a cylindrical form along the loci of the leading ends of the stirring blades 5a, 5b and the upper part of the container 1 is formed into a circular arc shape.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a stirring device used for mixing and stirring powder and granular materials, solid-gas reactions, solid-solid reactions, solid decomposition reactions, and the production of granular polymers.

As a device for such purposes, generally.

A high mixing speed between the powder and granules, good contact between the gas or liquid substance and the granules, and a large heat transfer ability (heat transfer area x heat transfer coefficient) of the powder and granules 2 Gas generated Fluidized bed equipment (hereinafter simply referred to as a fluidized bed), which fluidizes powder and granules by blowing in a large amount of gas, is widely used because of the high performance requirements such as high separation speed of steam and powder from powder and granules. has been done.

However, fluidized beds require the injection or circulation of a large amount of gas, which not only requires a large-capacity compressor, its power, and a device to remove fines accompanying the gas, but also requires a large amount of gas for fluidization. It cannot be applied to reactions that dislike blowing.

An apparatus (hereinafter simply referred to as an agitated fluidized bed) that forms a fluidized state substantially similar to that of a fluidized bed by only mechanically stirring the fluidized bed (hereinafter simply referred to as an agitated fluidized bed). 157-157605 and 7301j, rapid dryer, F'0RBERG instantaneous mixer) are known. In an agitated fluidized bed, when a conductive heat exchange member is inserted into the bed, the shape and arrangement of the heat exchange member will significantly affect the flow, so it is important to prevent contact between the heat exchange member and the granular material. to bring it to a favorable state.

In addition, in the case of particles with high adhesion or stickiness, there are restrictions on the shape and arrangement of the heat exchange member in order to forcibly scrape off the powder adhering to the surface of the heat exchange member. Thick.

As a conductive heat exchange member to be inserted into an agitated fluidized bed, thin tubes configured in a loop shape such as a U-shape, a V-shape, or a spiral shape are conventionally known (as disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 1983-1999). 7
As a result of study, the present inventors found that a shape in which a disc-shaped member is connected to two rotating shafts in the shape of a solo bread ball is suitable. Such a hollow disc-shaped heat exchange member through which a heat exchange medium flows.

Conventionally, it is known that stirring devices for powder and granular materials for the purpose of drying etc. are rotated at a relatively low speed (for example, February Shima Kikai rotary desk groove type dryer).

(Earth Machinery Disc Dryer, Hosokawa Micron Torrance Disc, Nara Machinery Paddle Dryer).

However, these stirring devices use paddle-shaped stirring blades provided on the outer periphery of a disk-shaped member for heat exchange to flow the powder and granules, but in both cases, the width of the stirring blade is narrow and the rotational speed is limited. Even if the temperature is increased, it is not possible to obtain the intense fluidity of the powder and granular materials as in an agitated fluidized bed, and as a result, the mixing speed and heat exchange efficiency of the powder and granular materials are severely limited. There is a problem that powder particles tend to adhere.

Generally, when powder or granules adhere to a heat exchange member as mentioned above, the attached powder or granules can be removed by attaching a fixed scraper separately or by bringing biaxially rotating heat exchange members close to each other. However, if the former scraper is installed separately, the scraper will obstruct the flow of the powder, so
The latter structure is preferable, in which the members rotating on two axes are placed close to each other and scrape each other.

A stirring device with a structure that scrapes off deposits from each other in this way,
It is especially used as a reactor for highly viscous substances. So-called self-cleaning type reaction equipment (for example,
No. 514, Special Publication No. 1972-20460, Special Publication No. 1977-3
No. 2185, JP-A No. 50-37888, JP-A No. 47-
24672), but all of these devices are designed to promote surface renewal by forcibly applying shearing force to highly viscous materials. However, it is not suitable as a reactor for powder or granular materials.

The present invention provides a powder stirring device that solves the above problems at once.

According to the present invention, a plurality of rotating shafts are provided in parallel passing through the side wall of the container, and disc-shaped members through which a heating or cooling medium flows are attached alternately to the respective rotating shafts. Adjacent disc-shaped members are arranged with parts of them overlapping each other, and 2 flat stirring blades having protruding pieces on both side ends are attached to the outer periphery of the disc-shaped members, and the protruding pieces are attached to the rotating shaft. The protruding pieces are attached in such a way that the projecting pieces are close to the side walls of adjacent disc-shaped members at the overlapping part of the disc-shaped members, and the lower part of the container is a partial cylinder along the trajectory of the tip of the stirring blade. It is configured.

There is provided a powder stirring device characterized in that the upper part of the container is formed in an arc shape.

The stirring device of the present invention has the following features.

■ By rotating the two-shaft stirring blades at high speed in the direction shown in Figure 2, for example, the powder and granules are swept along both side walls parallel to the axis of rotation of the container, and are moved up to the center of the container. Violent collision/
Flow pattern C that merges and descends is referred to as forced circulation flow. ) to form a stirred fluidized bed exhibiting This agitated fluidized bed has characteristics comparable to conventional fluidized beds, in particular, the heat transfer rate between the powder and the disk-shaped member for heat exchange is high, and the mixing and agitation of the powder and granules is also good. 2 For example, the liquid added as necessary as a reactant can be quickly dispersed, there is little temperature unevenness in the powder, so-called local overheating and dead space can be avoided, the processing capacity is large, and A homogeneous product can be obtained.

■ The heat exchange member is disc-shaped, and the stirring blade and the disc-shaped member are rotated close to each other to scrape off the powder adhering to the disc-shaped member (so-called self-cleaning structure). Since it also consists of a partial cylinder, it can be equipped with a scraper if necessary, covering most of the heat transfer surface.

It has a structure that can forcibly scrape off adhering powder and granules. Therefore, it is possible to process powder and granular materials with large adhesion and viscosity.

■ The flow of powder and granules in forced circulation flow is extremely stable. There is a wide range of possibilities.

Next, the present invention will be explained based on drawings showing one embodiment thereof.

The container 1 is provided with twelve rotating shafts 3a+3b extending in parallel through both side walls of the container 1, to which a jacket 2 for circulating a heating or cooling medium is attached as necessary. The rotating shaft 3a1 lobe b is supported by a bearing 4. The spacing between the rotating shafts 3a and 3b is determined by the stirring blades 5a+, which will be described later.
The locus (rotation circle) of the tip of 5b is the other rotation axis 3a, 3b
It is preferable to be close to . It is also possible to provide two rotating shafts beyond the filter shaft, but since there is no significant difference in stirring performance, two rotating shafts are practically sufficient.

Rotating shaft 3a,'! Disc-shaped members 6a and 6b through which a heating or cooling medium flows are alternately attached to Ib.

The disk-shaped members 6a+6b are arranged in such a way that some of them overlap each other. The insides of the rotating shafts 3a+3b and the disk-shaped members 6a+6b are as follows.

For example, as shown in FIG. 4, it has a structure in which a heating or cooling medium flows. At one end of the rotating shafts 3a and 3b,
The heating or cooling medium is transferred to the rotating shaft 3a.

A rotary joint 17 is attached for supplying and discharging to and from the disk-shaped members 3b and 6a+6b.

The size and number of the disc-shaped members 6a+6b can be appropriately determined by those skilled in the art, taking into consideration the amount of heat to be heated or removed.

There are two protruding pieces 7 on the outermost periphery of the disc-shaped member 6a16b and two protruding pieces 7 on both side ends.
A flat stirring blade 5a'+5b having a diameter of a+7b is attached with the protruding piece 7a+7'b facing the rotating shaft 3a+3+). -Also, the protruding pieces 7a+7b.

They are provided so as to be close to the side walls of the adjacent disc-shaped members 6a and 6b. That is, the protruding piece 7a is connected to the disc-shaped member 6.
b, and the protruding piece 7b is provided close to the side wall of the disc-shaped member 6a. The flat stirring blades 5a+5b1 are normally installed parallel to the rotating shaft 3a, but in order to promote the movement of the powder in the direction of the rotating shafts 3a+3b within the container 1, they may be tilted in the axial direction. It is also possible to use a combination of parallel blades and inclined blades. Stirring blade 5a+
5b and the number of stirring blades 5a, 5b and disk-shaped member 6a,
The relative dimension in the radial direction of 6b is the stirring blade 5a + 5
The surface area of the disk-shaped member 61)+6a scraped by the protruding pieces 7a+7b of b is maximized, and both the stirring blades 5a+5b and the disk-shaped member 6b.

6a is appropriately determined so that contact does not occur due to rotation.

The lower part of the container 1 is formed of a partial cylinder along the locus of the tips of the stirring blades 5a and 5b. It consists of a partial cylinder. The limit for partial cylinders is up to 1/2 cylinder. The gap between the lower part of the container 1 and the tips of the stirring blades 5a+5b is preferably as small as possible, and is generally 10 mm or less.

The upper part of the container 1 is formed into an arc shape. Especially rotation axis 3
It is preferable that the upper part of the container 1 is constituted by a partial cylinder whose diameter is the distance between the container walls on a horizontal line passing through the centers of points a and 3b.

A weir 8 is provided on one side wall of the container 1, and a powder extraction nozzle 9 is provided in communication with the weir 8. Note that the powder extracting device is not limited to what is shown in the figure, and may be placed, for example, at the bottom of the container 1.

An extraction nozzle passing through the jacket 2 can also be provided.

Although the axial length of the container 1 is arbitrary, there are usually 9 stirring blades 5a.
, 5'b is suitably 1 to 7 times, particularly 1.5 to 5 times, the diameter of the rotation circle. Although the container 1 is preferably installed horizontally, it can also be installed at an inclination of no more than 10° from the horizontal for the purpose of promoting movement of the powder in the axial direction.

Next, the method of operating the stirring device of the present invention will be explained by taking formaldehyde polymerization as an example.

Gaseous formaldehyde and known polymerization catalysts are fed into vessel 1 through nozzles 10 and 11, respectively.

If necessary, a comonomer is supplied to the container 1 from a nozzle (not shown).

The rotating shafts 3a, 3b are rotated at a constant speed by a drive device (not shown). Rotating shaft a,'! The direction of rotation of Ib may be arbitrary, but from the point of view of uniformity of stirring, it is preferable to rotate both shafts in opposite directions.
It is particularly preferable to rotate the rotation shaft 3b counterclockwise while rotating the shaft 3b clockwise. The rotational speed of the rotating shafts 3a and 3b is
Stirring blade 5a.

The tip speed of 5b is preferably 1 to 5 m/sec.).

The amount of formaldehyde polymer in the container 1 may be any amount as long as a sufficient stirring effect can be obtained.

While the stirring blades 5a+5b are stopped, the stirring blade 5a.

It is preferable that the amount is less than or equal to the position near the highest point drawn by 5b.

In the container 1, the formaldehyde polymer is stirred by the stirring blades 5a,
5b to form a forced circulation flow.

Polymerization reaction heat is supplied to the jacket 2 through the nozzle 12 and is discharged through the nozzle 13 as a cooling medium.

The cooling medium is supplied from the nozzle 14 to the disc-shaped members 6a and 6b via the rotary shaft filter a+3b, and is removed by the cooling medium discharged from the nozzle 15. In the present invention, the bomaldehyde polymer violently collides with the entire disc-shaped member 6a + 6b, and the heat transfer surface itself rotates, so that the sliding force of the powder increases, and moreover, the heat transfer surface is uniformly fluidized. come into contact with.

For this reason, there is less formaldehyde polymer adhesion to the heat transfer surface, the heat transfer surface can be easily updated, and the heat transfer coefficient can be increased by disturbing the interface, making it possible to effectively remove polymerization heat. be.

The produced polymer is extracted through the nozzle 9.

Unreacted gas is discharged through the nozzle 16.

Although the case where the stirring apparatus of the present invention is used as a polymerization reactor has been described above, the stirring apparatus of the present invention can also be used for thermal decomposition reactions of powdery solid substances. In this case, since the particulate solid material forms an agitated fluidized bed, the gaseous material produced by the thermal decomposition reaction is easily moved.

This movement can be avoided from controlling the reaction rate. In addition, this device has a large amount of heat transfer per unit volume (heat transfer area x heat transfer coefficient 5), and it is easy to supply the amount of heat necessary for the thermal decomposition reaction, and also has good stirring and mixing.
The amount of reaction per unit volume of the device is high, and the reaction within the device can be made uniform.

Furthermore, the stirring device of the present invention can be used for grains, agricultural chemicals, cement, etc.
Mixing of synthetic resins, etc. and various additive substances.

Drying of pulverized coal, crystalline ammonium sulfate, various synthetic resins, etc.

It can be used for gas phase polymerization of oleoin.

In addition to this, there are also mixers for uniformly mixing two or more types of powder or granular materials, reactions between gaseous substances and powdered solid materials, reactions between different types of powdered solid materials, and decomposition reactions of powdered or granular solid materials. , it can be used as a reactor in the production of powdery polymers.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a cross section parallel to the rotation axis of the stirring device of the present invention, FIG. 2 is a schematic diagram corresponding to the A-A cross section of FIG. 1, and FIG. . FIG. 2 is a schematic partial plan view showing an example of the phase-specific positional relationship between the stirring blade and the rotating shaft, and the shape of the stirring blade. FIG. 4 is a sectional view showing an example of the structure of the disc-shaped member. 1... Container, 3a, 3b... Rotating shaft, 5a. 5b... Stirring blade + 6a, 6b... Disc shaped member. 7a, 7b...Protruding pieces. Patent applicant: Ube Industries, Ltd. Figure 2 left α

Claims (1)

[Claims] A plurality of rotating shafts are provided in parallel through the side wall of the container, and disc-shaped members through which a heating or cooling medium flows are attached alternately to each rotating shaft, and adjacent disc-shaped members Two plate-shaped agitating blades are arranged with their parts overlapping each other, and have projecting pieces on the outer periphery of the two disc-shaped members. At the overlapping part, the protruding pieces are attached so as to be close to the side walls of the adjacent disc-shaped members, and the lower part of the container is composed of a partial cylinder that extends along the trajectory of the tip of the stirring blade, and the upper part of the two containers is A stirring device for powder and granular material, characterized in that the is formed in an arc shape.