JP4918226B2 - Media agitation type wet crusher - Google Patents

Description

  The present invention relates to a media agitation type wet pulverizer, and more particularly to a media agitation type wet pulverizer that continuously performs pulverization and dispersion treatment.

  The media agitation type wet pulverizer that pulverizes and disperses the processed product by putting the processed product to be pulverized into the pulverization tank together with the pulverizing media, and stirring the processed product and the pulverized media together. It is often used in the field of fine pulverization, such as dispersion of ceramics, pulverization and dispersion of ceramics and new materials and electronic materials, pulverization and dispersion of metals and inorganic substances, pulverization and dispersion of toners, and pulverization and dispersion of pharmaceuticals.

A media agitation type wet pulverizer includes a pulverization tank, an agitation member, a separator, and the like, and various forms have been proposed depending on the shape and combination thereof (for example, refer to Patent Document 1).
Patent Document 1 discloses a horizontal cylindrical crushing tank, a cylindrical stirring member that is coaxially rotated with the crushing tank and closed at one end, and a cylindrical separator that is located in the cylinder on the other end side of the stirring member Has been proposed.

  Recently, in each field, there is an increasing need to set the particle size of the processed material to the nm (nanometer) order. In the media agitation type wet pulverizer, it is known that the particle size of the pulverized product is proportional to the diameter of the pulverized media. In order to reduce the particle size of the processed product to the order of nm, the media diameter is 0.1 mm or less. It is empirically known that it is necessary to.

  When the media diameter is reduced in this manner, pulverization becomes difficult and separation of the pulverized material and pulverized media becomes difficult. When separating using a sieving separator as shown in Patent Document 1, the gap of the sieving needs to be 1/3 or less of the diameter of the grinding media, and the media diameter is 0.1 mm. In that case, a separator having a mesh gap of 0.03 mm is required.

However, if the gap is 0.03 mm or less with a sieve separator, there are the following problems, and in particular, there is a big problem that stable continuous operation is not possible.
(1) Since production is difficult, it becomes very expensive.
(2) It becomes a very large separator in order to ensure the passage area of the processed material.
(3) Since the gap is remarkably narrow, it is easy to bite and clog.
(4) Since crushed media accumulate in the gap, (2) and (3) are further promoted.

Further, a media agitation type wet pulverizer using a centrifugal separator instead of a sieve separator has been proposed (see, for example, Patent Document 2).
Patent Document 2 proposes a media stirring wet pulverizer in which two classification rotors are attached to a stirring shaft for pulverization so as to have a concentric double structure. The classification rotor has a plurality of slits formed on the same circumference, and the space inside the slit communicates with a discharge port near the stirring shaft. Therefore, the pulverized small particles pass through the slit and reach the discharge port, but the pulverized media and unpulverized large particles receive the centrifugal force due to the rotation of the slit and cannot pass through the slit. can do.

Centrifugal separators are excellent in that they can be stably operated continuously without worrying about clogging unlike the sieve separator. However, the disadvantage is that the classification performance cannot be increased. Although the classification rotor described in Patent Document 2 can separate 0.1 mm grinding media (zirconia beads), this is limited to a case where the processing amount is extremely small, and a large amount of processing and high classification are performed. Realizing performance at the same time is difficult.
JP 7-299375 A JP-A-11-128760

  An object of the present invention is to improve the performance of a continuous media agitation type wet pulverizer, and by devising the structure and arrangement of the pulverization tank, pulverization rotor, centrifugal separator and the like, a large-capacity treatment is achieved. Another object is to provide a media agitation type wet pulverizer that simultaneously achieves high classification performance.

In order to solve the above-described problems, the media agitation type wet pulverizer according to claim 1 of the present invention is formed such that a pulverization chamber having an annular cross section and a separation chamber having a circular cross section are adjacent to each other on the same axis. A crushing tank, a hollow rotating shaft coaxially and rotatably provided in the separation chamber, an open one end side located in the crushing chamber, and a closed other end side located in the separation chamber. a cylindrical grinding rotor fixed to the rotary shaft, a medium agitation type wet pulverizer and a centrifugal separator that is fixed to the rotary shaft in the grinding rotor, and out the pulverizing tank of the crushing tank the includes a supply port communicating, prior Symbol milling rotor, the portion located on the separation chamber comprises a plurality of openings for communicating the inside and outside of a plurality of blades and said grinding rotor that generates centrifugal force by rotation, the centrifugal The separator can be And a centrifugal force is generated by rotation and the processed material is circulated from the outer peripheral portion toward the shaft core, and a space is formed inside the blade, and the rotation shaft A means is adopted in which the hollow portion communicates with the space portion to form a discharge port .

  Further, the media agitation type wet pulverizer according to claim 2 of the present invention is the media agitation type wet pulverizer according to claim 1, wherein the blade of the pulverization rotor is placed in the pulverization chamber more than the blade of the centrifugal separator. The means provided in the close position is adopted.

  Furthermore, the media agitation type wet pulverizer according to claim 3 of the present invention is the media agitation type wet pulverizer according to claim 1 or 2, wherein the pulverization rotor is disposed at an outer peripheral portion of a portion located in the pulverization chamber. A means having a plurality of protrusions is employed.

The media agitation type wet grinding machine according to claim 4 of the present invention, in the media-agitation type wet pulverizer according to any one of claims 1 to 3, wherein the supply port is provided in the separation chamber Adopting means.

Furthermore, media-agitation type wet grinding machine according to claim 5 of the present invention, in the media-agitation type wet pulverizer according to any one of claims 1 to 4, wherein the crushing tank, jacket cooling on the outside The means equipped with is adopted.

  In the present invention, the processed material circulates inside and outside the grinding rotor in the grinding tank, and the large particles separated by the centrifugal separator return to the grinding chamber. As a result, the classification performance of the centrifugal separator is dramatically improved, and a large capacity treatment and a high classification performance can be realized at the same time.

Hereinafter, embodiments of the present invention shown in the drawings will be described.
FIG. 1 and FIG. 2 show an embodiment of a media agitation type wet pulverizer according to the present invention. FIG. 1 is a schematic sectional view of the media agitation type wet pulverizer, and FIG. -A schematic cross-sectional view taken along line A. The media agitation type wet pulverizer 1 includes a pulverization tank 2, a rotating shaft 3, a pulverization rotor 4, a centrifugal separator 5, and the like.

  In the pulverization tank 2, a pulverization chamber 81 having an annular cross section and a separation chamber 82 having a circular cross section are formed adjacent to each other on the same axis. In the figure, one end of a double cylinder composed of an inner cylinder 21 and an outer cylinder 22 on the same axis is closed by an end plate 23, and the other end of the inner cylinder 21 is closed by an end plate 24 in the outer cylinder 22. Has been. Further, a lid member 26 is attached to the other end of the outer cylinder 22 via a flange 25, and the other end portion of the outer cylinder 22 is substantially closed. Thus, the crushing chamber 81 having an annular cross section is formed in the double cylinder portion, and the separation chamber 82 having a circular cross section is formed only in the outer cylinder 22 portion.

  Thus, in the media agitation type wet pulverizer of the present invention, the pulverization tank 2 is clearly divided into the pulverization chamber 81 and the separation chamber 82. Further, the pulverization tank 2 is provided with a supply port 27 for processed material. The attachment position of the supply port 27 is preferably provided in the separation chamber 82, and particularly preferably provided in the lid member 26 as shown in the figure.

  The lid member 26 is formed in a substantially cylindrical shape having a hollow inside, and a hollow rotary shaft 3 is rotatably provided at the axial center of the hollow portion. A shaft seal 33 is interposed between the outer peripheral surface of the rotating shaft 3 and the inner peripheral surface of the lid member 26 so that the crushing tank 2 can be sealed.

  The rotating shaft 3 is provided so as to be coaxial with the crushing chamber 81 and the separation chamber 82, and one end thereof is located in the separation chamber 82, and a crushing rotor 4 and a centrifugal separator 5 described later are attached thereto. The other end of the rotating shaft 3 is located outside the crushing tank 2 and a drive device is attached (not shown).

  The crushing rotor 4 is fixed to the rotary shaft 3 with one end side opened in the crushing chamber 81 and the other end side closed in the separation chamber 82. That is, the crushing rotor 4 is composed of a cylindrical rotor body 41 and a holding member 42, one open end side of the crushing rotor 4 is located in the crushing chamber 81, and the other end side closed by the holding member 42 is a separation chamber. The holding member 42 is fixed to the rotating shaft 3.

  One end of the rotor body 41 is located in the vicinity of the end plate 23 of the crushing chamber 81 so that the entire crushing chamber 81 can be agitated. Further, in the separation chamber 82, a distance is provided between the holding member 42 and the end plate 24 of the crushing tank 2, and a space for attaching a centrifugal separator 5 described later is formed.

  The inside of the crushing chamber 81 having an annular cross section is divided into two zones, the inside and outside, by the cylindrical rotor body 41 and is efficiently stirred. That is, the processed material flowing into the pulverization tank 2 from the supply port 27 flows so as to flow from the separation chamber 82 to the pulverization chamber 81 outside the rotor body 41, and from the pulverization chamber 81 to the separation chamber 82 inside the rotor body 41. It will flow like a spill.

  In order to enhance the pulverization performance in the pulverization chamber 81, the pulverization rotor 4 is preferably provided with a protrusion 43 for stirring on the rotor body 41 located in the pulverization chamber 81. You may provide the location which attaches the protrusion 43 in the inner peripheral part or outer peripheral part of the rotor main body 41, or both an inner peripheral part and an outer peripheral part. Further, a protrusion can be provided on the peripheral wall surface of the grinding chamber 81 (the outer peripheral surface of the inner cylinder 21 or the inner peripheral surface of the outer cylinder 22) facing the protrusion 43 attached to the rotor body 41 (not shown). By providing these protrusions, the pulverization media can be efficiently stirred even when the viscosity increases due to fine pulverization.

  The pulverization rotor 4 of the media agitation type wet pulverizer of the present invention is characterized in that the rotor body 41 located in the separation chamber 82 includes a plurality of blades 44 and a plurality of openings 45 that generate centrifugal force by rotation. Yes. The plurality of blades 44 and the openings 45 generate a centrifugal force to cause the processed material to flow from the inside to the outside of the rotor body 41. It is also effective to increase the separation efficiency by increasing the centrifugal force with a taper that increases the inner diameter of the rotor body 41 toward the holding member 42 side.

  Then, the processed material that flows out from the crushing chamber 81 to the separation chamber 82 inside the rotor main body 41 receives the centrifugal force of the blade 44 and flows from the opening 45 toward the outside of the rotor main body 41. It will circulate between the inside and the outside. As a result, the large particles separated in the separation chamber 82 are returned to the pulverization chamber 81 and pulverized again, so that the classification efficiency is improved.

  The centrifugal separator 5 generates centrifugal force by rotation, and can circulate a processed material from the outer peripheral portion toward the shaft core, and can classify solid particles by centrifugal force. As shown in the figure, a plurality of blades 51 are arranged on a rotating disk 52 at regular intervals. The bolt 53 is fixed to the rotary shaft 3 together with the grinding rotor 4.

  Since the blade 51 of the centrifugal separator 5 is located slightly away from the outer surface of the rotating shaft 3, a space portion 54 is formed inside the blade. The hollow portion 31 of the rotary shaft 3 communicates with the space portion 54 of the centrifugal separator 5 through the opening 32 to form the discharge port 34.

  The blade 44 of the crushing rotor 4 and the blade 51 of the centrifugal separator 5 are set at substantially the same position in the axial direction. This is because large particles separated by the centrifugal separator 5 can be quickly returned to the crushing chamber 81. It is particularly effective to provide the blade 44 at a position slightly closer to the crushing chamber 81 than the blade 51. This is because large particles can be separated in advance by the blade 44 before the processed material enters the centrifugal separator 5.

  Members that are in direct contact with the processed material such as the pulverization tank 2, the pulverization rotor 4, and the centrifugal separator 5 are preferably made of a wear-resistant material, and ceramics such as alumina, alumina zirconia, and silicon carbide are used. Thereby, it can prevent that an impurity mixes in a product.

  The media agitation type wet pulverizer of the present invention can perform a powerful agitation operation in a relatively narrow pulverization chamber 81. Therefore, it is preferable to forcibly cool the crushing chamber 81, and it is preferable to provide a cooling jacket 6 outside the crushing tank 2 as shown in the figure. The cooling jacket 6 covers the entire pulverization chamber 81 and is provided with a water supply port 61 and a drain port 62 so as not to drift. The jacket 6 makes it possible to control the temperature of the processed material, and can also be used for heating at the beginning of the processing.

A test for crushing titanium oxide (average particle size 2.4 μm) under the working conditions shown in Table 1 was performed using the media stirring type wet crusher of the present invention, and the crushing performance was confirmed.
The prepared slurry is put into the holding tank, introduced into the supply port of the crusher with a metering pump, a circulation system is formed to return the slurry discharged from the discharge port of the crusher to the holding tank again, and the crushing rotor is started in this state And tested.

  After starting the grinding rotor, samples were taken from the holding tank every predetermined time. The particle diameter was measured by a laser diffraction and light scattering method using a microtrack MKIIDRA manufactured by Nikkiso Co., Ltd.

  A zirconia ball having a particle diameter of 0.03 mm was used as a grinding medium, and this was filled to 53.7% with respect to the volume of the grinding chamber, and a grinding treatment test was performed with the number of revolutions of the grinding rotor being 1600 rpm. As a result, the average particle diameter of the treated product was 49.1 nm in 90 minutes from the start of operation, and there was no mixing of the grinding media.

  A zirconia ball having a particle diameter of 0.05 mm was used as a grinding medium, and this was filled with 29.3% with respect to the volume of the grinding chamber, and a grinding treatment test was performed at a rotational speed of the grinding rotor of 2640 rpm. As a result, the average particle diameter of the treated product was 64.3 nm in 90 minutes from the start of operation, and there was no mixing of the grinding media.

  A zirconia ball having a particle diameter of 0.10 mm was used as a grinding medium, and this was filled with 29.3% of the volume of the grinding chamber. As a result, the average particle diameter of the treated product was 52.4 nm in 90 minutes from the start of operation, and there was no mixing of the grinding media.

It is a schematic sectional drawing which shows an example of implementation of the media stirring type wet crusher of this invention. It is the schematic sectional drawing seen along the AA line shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Media stirring type wet crusher 2 Crushing tank 3 Rotating shaft 4 Crushing rotor 5 Centrifugal separator 6 Jacket 7 Crushing media 21 Inner cylinder 22 Outer cylinder 23 End plate 24 End plate 25 Flange 26 Cover member 27 Supply port 31 Hollow part 32 Opening 33 Shaft seal 34 Discharge port 41 Rotor body 42 Holding member 43 Projection 44 Blade 45 Open 46 Key 51 Blade 52 Rotating disk 53 Bolt 54 Space portion 61 Water supply port 62 Drain port 81 Crushing chamber 82 Separation chamber

Claims (5)

A crushing tank in which a crushing chamber having an annular cross section and a separation chamber having a circular cross section are formed adjacent to each other coaxially;
A hollow rotating shaft provided coaxially and rotatably in the separation chamber;
A cylindrical crushing rotor whose one end opened is positioned in the crushing chamber and whose other end capped is positioned in the separation chamber and fixed to the rotating shaft;
A media-agitation type wet pulverizer and a centrifugal separator that is fixed to the rotary shaft in the grinding rotor,
The pulverization tank includes a supply port for communicating the inside and outside of the pulverization tank ;
Before SL milling rotor, the portion located on the separation chamber comprises a plurality of openings for communicating the inside and outside of a plurality of blades and said grinding rotor that generates centrifugal force by rotation,
The centrifugal separator is provided with a plurality of blades, generates centrifugal force by rotation, and distributes a processed material from the outer peripheral portion toward the shaft core, and a space portion is formed inside the blade. And
A media stirring type wet pulverizer , wherein a hollow portion of the rotating shaft communicates with the space portion to form a discharge port .   The media stirring type wet pulverizer according to claim 1, wherein the blade of the pulverization rotor is provided at a position closer to the pulverization chamber than the blade of the centrifugal separator.   The media stirring type wet pulverizer according to claim 1 or 2, wherein the pulverization rotor includes a plurality of protrusions on an outer peripheral portion of a portion located in the pulverization chamber. It said supply port, media-agitation type wet pulverizer according to any one of claims 1 to 3, characterized in that provided in the separation chamber. The grinding tank, media-agitation type wet pulverizer according to any one of claims 1 to 4, characterized in that it comprises a cooling jacket on the outside thereof.

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