Processing device

Abstract

To provide a processing device capable of suppressing a decrease in recovery rate by preventing adhesion and accumulation of a processing object on the body wall surface of a mixing tank.SOLUTION: A processing device 10 performs a process of colliding particulates to be processed with each other. The processing device comprises a vertical mixing tank 20, a rotating shaft 30 inserted through the bottom of the mixing tank, a plurality of stirring blades 40 attached to the rotating shaft, and collision plates 50 disposed above the stirring blades, and the collision plates can rotate along the body wall surface of the mixing tank during processing. The processing device also includes scrapers 60 which are provided on the collision plates and rotate together with the collision plates.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a processing apparatus for performing a process of colliding powder or granular material to be processed. [Background technology]

[0002] The compounding and spheroidization of powder particles is carried out by applying compressive and shearing forces to micron- or nano-order powder particles through collision. By applying compressive and shearing forces to particles through collision, the particles can be pulverized to reduce the aspect ratio and remove corners to make them rounder. It also makes it possible to break down and finely disperse aggregated particles.

[0003] At the same time, the particles can be bonded together by applying compressive and shear forces to them through collision. In particular, when compressive and shear forces are applied to a mixture of large and small particles through collision, the surfaces of the large particles become covered with the small particles and are integrated together. In the following explanation, the large particles are referred to as "mother particles" and the small particles as "child particles."

[0004] Particles before processing or aggregated particles often have spaces between them, low bulk density, and large specific surface area. In contrast, particles integrated by collision tend to have child particles driven into the surface of the mother particle, or child particles are integrated with no gaps between them, resulting in particles with high bulk density and small specific surface area.

[0005] By integrating the mother particle and the child particle, the particle is generally made into a spheroid. When the mother particle and the child particle are different in type, this can be called a particle composite process. It is not rare to carry out the composite process using two or more types of child particles.

[0006] By covering the surface of the mother particle with the child particles, the surface of the composite particle has the properties of the child particles, which is sometimes called a surface modification treatment. When the mother particle is made of a soft material such as resin, the child particles can be fixed in a state where they are completely embedded in the mother particle. On the other hand, when the mother particle is made of a hard material and the child particles are made of a material that is easily deformed, the child particles are integrated with each other, which may be called an encapsulation treatment.

[0007] Patent Document 1 describes a processing device for compounding and spheronizing powder particles. This processing device includes a vertical mixing vessel, a rotating shaft that passes through the bottom of the mixing vessel, multiple stirring blades that are attached to the rotating shaft, and multiple collision plates that are fixed to the mixing vessel.

[0008] The powder and granules are subjected to inertial force by the rotation of the agitator blades, and rise from the corners of the tank bottom along the wall surface, then drop back down to the center of the mixing tank, repeating this circulatory flow. Since multiple collision plates are fixed inside the mixing tank, the flowing powder and granules collide with the collision plates and are subjected to compressive and shearing forces. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] Patent No. 5575139 Summary of the Invention [Problem to be solved by the invention]

[0010] However, in a treatment device using an impact plate, adhesion or deposition may occur on the wall surface of the mixing vessel, which may cause a problem of a decrease in the recovery rate, particularly for highly adhesive materials.

[0011] Therefore, an object of the present invention is to provide a treatment device capable of suppressing a decrease in the recovery rate by preventing adhesion and accumulation of the treatment material on the barrel wall surface of the mixing tank. [Means for solving the problem]

[0012] In order to achieve the above-mentioned object, the processing apparatus of the present invention is a processing apparatus for performing a process in which powder or granular material to be processed is collided, and is characterized in that it comprises a vertical mixing tank, a rotating shaft inserted through the bottom of the mixing tank, a plurality of stirring blades provided on the rotating shaft, and a collision plate disposed above the stirring blades, and the collision plate is capable of rotating along the body wall surface of the mixing tank during processing.

[0013] Here, the configuration may include a scraper formed above the collision plate and rotating together with the collision plate. The rotation of the collision plate may be in one direction, or in one direction and stopped. The rotation of the collision plate may be a reciprocating rotation within a predetermined angle range, or a reciprocating rotation and stop. Effect of the Invention

[0014] In the treatment device of the present invention thus configured, the collision plate is rotated along the body wall surface of the mixing tank during treatment, and the state of the body wall surface adjacent to the collision plate can be changed. That is, the region of the body wall surface where adhesion is likely to occur can be changed to a body wall surface with a cleaning effect by the moving collision plate. Therefore, in the vicinity of the region where the collision plate rotates, the state where adhesion is likely to occur is no longer sustained over the entire circumference of the body wall surface, and adhesion and accumulation can be prevented.

[0015] In addition, a scraper that rotates along the wall surface of the barrel can be added as a component by utilizing the mechanism that rotates the collision plate. This makes it possible to completely remove even the finest deposits not only from the vicinity of the area where the collision plate rotates but also from a wide area of ​​the barrel wall. [Brief description of the drawings]

[0016] [Figure 1]1A and 1B are diagrams illustrating an example of a schematic configuration of a processing apparatus according to an embodiment of the present invention, in which (a) is a schematic vertical cross-sectional view, and (b) is a schematic horizontal cross-sectional view taken along the direction of the arrow AA in (a). [Diagram 2] 1A and 1B are diagrams illustrating an example of a pivoting mechanism for an impact plate, in which (a) is a schematic plan view and (b) is a schematic elevation view. [Diagram 3] 1A is an explanatory diagram showing the positional relationship between the collision plate and the wall surface of the barrel, FIG. 1B is an explanatory diagram showing an enlarged view of the positional relationship between the collision plate and the stirring blades, and FIG. 1C is an explanatory diagram viewed in the direction of the CC arrow in FIG. [Figure 4] 10A and 10B are diagrams for explaining examples of the cross-sectional shape and rotation direction of the scooping surface of a scraper, where (a) and (b) are explanatory diagrams showing the case in one direction, and (c) is an explanatory diagram showing the case in both directions. [Diagram 5] 10A and 10B are diagrams showing another example of a pivot mechanism for an impact plate, in which (a) is a schematic plan view and (b) is a schematic elevation view. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is an explanatory diagram showing a schematic configuration of a processing apparatus 10 according to an embodiment of the present invention, in which FIG. 1(a) is a schematic vertical sectional view and FIG. 1(b) is a schematic horizontal sectional view seen in the direction of the arrow AA.

[0018] The processing apparatus 10 according to the embodiment of the present invention is a powder / granular material processing apparatus capable of performing advanced processing such as particle compounding and spheronization by performing a process of colliding powder / granular material to be processed (a process of applying a compressive force and a shear force between particles). For example, the processing apparatus 10 can perform a particle spheronization process in which child particles are collided with the surface of a mother particle to adhere to it, and a compounding process in which different types of particles are collided with each other to adhere to them.

[0019] The processing apparatus 10 according to the embodiment of the present invention comprises a vertical mixing tank 20, a rotating shaft 30 inserted through the bottom of the mixing tank 20, a plurality of stirring blades 40 attached to the rotating shaft 30, an impingement plate 50 disposed above the stirring blades 40, and a rotating mechanism for rotating the impingement plate 50 along the body wall surface 23 of the mixing tank 20 during processing.

[0020] The mixing vessel 20 is a cylindrical vessel formed around a vertical axis. In general, a cylindrical vessel with a horizontal axis is called a "horizontal type," and a cylindrical vessel with a vertical axis is called a "vertical type."

[0021] Mixing tank 20 is provided with an openable and closable lid 25 at the top to allow for internal maintenance and inspection. Mixing tank 20 can be sealed or opened by a flange 21 of mixing tank 20 and a flange 26 of lid 25. In order to heat or cool the material to be treated, the tank wall of mixing tank 20 may have a jacket structure through which a heat transfer medium circulates, or a coil through which a heat transfer medium circulates may be provided inside mixing tank 20.

[0022] In the processing device 10, batch processing is performed instead of continuous processing. For this purpose, a powder inlet (not shown) is provided in the lid 25, and the powder as the raw material is introduced through this inlet. In addition, the lid 25 is appropriately provided with an inspection hatch, a sight glass, an exhaust port, etc.

[0023] In addition, a discharge port (not shown) is provided in a corner near the bottom of the mixing tank 20, through which the treated powder or granular material is discharged. When discharging the powder or granular material, a discharge valve (not shown) is opened while the agitating blade 40 is rotating slowly, so that the powder or granular material can be reliably discharged.

[0024] Mixing tank 20 is placed on a stand together with an electric motor (not shown), and the power of the electric motor is transmitted to rotating shaft 30 by a transmission device such as a V-belt. It is preferable that the rotation speed of rotating shaft 30 is variable so that it can be freely set.

[0025] The rotating shaft 30 is sealed against the mixing vessel 20 by a gland seal, an air seal, or the like (not shown). When gas is used, it is preferable to provide an exhaust port equipped with a filter on the lid 25 in order to collect fine powder entrained in the exhaust gas from the mixing vessel 20.

[0026] The agitator blades 40 are arranged on the inclined surface of a boss portion 46 which is formed in a substantially conical shape, and the boss portion 46 is attached to the rotating shaft 30 so that the bottom surface of the boss portion 46 rotates close to the bottom of the mixing tank 20.

[0027] The powder and granular material in the tank is subjected to a circumferential inertial force by the rotation of the agitator blade 40, so it rises along the cylindrical body wall surface 23 and falls into the center of the mixing tank 20. The falling powder and granular material are again subjected to an inertial force by the agitator blade 40, so a circulating flow of powder and granular material is formed inside the mixing tank 20.

[0028] The plurality of agitating blades 40 are preferably connected by a ring-shaped upper plate 47. In this case, the powder flows between the agitating blades 40 so as to pass under the ring-shaped upper plate 47, thereby obtaining a stable flow state. The rotation speed of the agitating blade 40 at its outer end is 20 m / s to 150 m / s, preferably 30 m / s to 100 m / s.

[0029] The processing device 10 of this embodiment is equipped with an impact plate 50 located above the agitating blade 40 and rotating along the body wall surface 23 of the mixing tank 20. The rotation mechanism of the impact plate 50 will be described later. By colliding the circulating material to be processed with the impact plate 50, it is possible to perform a process in which particles collide with each other, which applies compressive and shearing forces to the powder or granular material. For the sake of explanation, the rotation direction of the agitating blade 40 is assumed to be counterclockwise.

[0030] The collision plate 50 of the processing device 10 has a rotating shaft 58 rotatably attached to the lid 25 via a bearing housing 59, and is driven by an electric motor 90 to rotate in one direction. An arm member 56 is fixed to the rotating shaft 58, and an adjustment member 57 is provided on the arm member 56. The collision plate 50 is attached to the adjustment member 57 together with a connecting member 55. The connecting member 55 can also be a scraper 60 that removes fine powder adhering to the body wall surface 23, as will be described later.

[0031] 2A and 2B show an example of the configuration of a rotation mechanism of the collision plate 50, with Fig. 2A being a schematic plan view and Fig. 2B being a schematic elevation view. The collision plate 50 and the scraper 60 will be described in detail below.

[0032] The collision plate 50 and scraper 60 preferably rotate close to the body wall surface 23, and the gap between them and the body wall surface 23 can be adjusted by an adjustment member 57. Here, the number of collision plates 50 is two, but the number of collision plates 50 is not limited, and may be one or more, or may be four or more as necessary.

[0033] In the following, a simple case where the collision plate 50 rotates in one direction will be described, but "rotation" includes various complex movements. For example, it may rotate in one direction and then stop repeatedly, or it may change the speed or the time it stops. It may also be a reciprocating movement, or a reciprocating movement with stops or speed changes. It may also be a programmed movement. And the rotation speed can be freely determined.

[0034] In the collision plate 50, the surface against which the circulating flow collides is called the collision surface 51, and the back side is called the back surface 52. Here, the collision surface 51 is shown to be located on a straight line passing through the axis of the rotating shaft 58 and to be angled with respect to the vertical plane. The orientation of this collision surface 51 can be freely determined, and it may be oriented so as to intersect with the straight line passing through the axis of the rotating shaft 58.

[0035] If the collision surface 51 is arranged at a right angle to the circulating flow of the powder, the force applied to the powder will be stronger, but the circulating flow will tend to become disturbed and unstable. If an inclination as described here is provided, the circulating flow will be suppressed slightly downward, resulting in a stable flow. Since the circulating flow flows in the rotation direction of the agitator blade 40, the inclination of the collision surface 51 is set to match this rotation direction.

[0036] Here, a case will be described in which the rotation direction of the collision plate 50 is clockwise, opposite to the rotation direction of the agitation blade 40, but they can also be in the same direction. In Fig. 2(a), the collision plates 50 are viewed from above, so the back surfaces 52 of both are visible. In Fig. 2(b), the collision plate 50 on the right side shows the collision surface 51, and the collision plate 50 on the left side shows the back surface 52.

[0037] In addition, in the scraper 60, the surface that scoops up the deposits is referred to as the scooping surface 61, and the surface behind it is referred to as the back surface 62. The scooping surface 61 has a shape suitable for scooping up or scraping off the deposits. At the same time, the scooping surface 61 is preferably shaped to serve as a guide for the circulating flow that passes through it. In addition, when the scraper 60 reciprocates together with the collision plate 50, the shape is adapted to the reciprocating motion.

[0038] In Fig. 2(a), the scraper 60 is viewed from above, so the scooping surface 61 can be seen in the direction of travel. In Fig. 2(b), the scraper 60 on the right side shows the scooping surface 61, and the scraper 60 on the left side shows the back surface 62.

[0039] Metals such as stainless steel can be used as the material for the collision plate 50 and the scraper 60. It is also possible to use resins with high heat resistance and low friction resistance, such as PEEK (polyether ether ketone).

[0040] Figure 3 is an explanatory diagram of the collision plate 50, where Figure 3(a) shows the positional relationship between the collision plate 50 and the body wall surface 23, Figure 3(b) is a partially enlarged view of Figure 1(a) showing the positional relationship between the collision plate 50 and the stirring blade 40, and Figure 3(c) is an explanatory diagram viewed in the direction of the CC arrow in Figure 3(b).

[0041] In FIG. 3(a), research by the present inventors has revealed that when processing is performed with the rotation of the collision plate 50 stopped, adhesion and accumulation occur near the upper part of the collision plate 50, i.e., near the arm member 56, the adjustment member 57, and the scraper 60.

[0042] In detail, it was found that adhesion and deposition were most likely to occur in the vicinity of the upper part of the collision plate 50, i.e., in the upper part of the body wall 23 of the mixing vessel 20, and that in the upper part of the body wall 23 of the mixing vessel 20, the circulating flow of the powder and granules becomes weak and sluggish, causing adhesion and deposition.

[0043] In addition, on the trunk wall surface 23 other than the above-mentioned region, although there is a cleaning action due to the uniform circulating flow, the circulating flow slows down and the cleaning action becomes weak due to the influence of the collision plate 50 and the scraper 60. Therefore, although adhesion and deposition tend to decrease, they cannot be prevented from occurring.

[0044] The collision plate 50 and scraper 60 rotate in the opposite direction to the agitator blade 40 as shown in FIG. 3(c). That is, because they rotate in the direction against the circulating flow of the powder and granular material, the circulating flow is actively disturbed in the vicinity of the collision plate 50 and scraper 60. In addition to the direct role of the scraper 60 in scooping up the powder, it also has a cleaning effect. That is, when processing is performed while the collision plate 50 is rotating, the above action is repeated in every location. Therefore, rotating the collision plate 50 is effective in preventing adhesion and accumulation of the processed material on the barrel wall surface 23, and it is possible to suppress a decrease in the recovery rate.

[0045] The effectiveness of the treatment in the treatment device 10 is greatly affected not only by the strength of the impact on the collision plate 50 but also by the flow state, but the following effective area can be defined and used to judge the effectiveness of the treatment. Here, the area of ​​the collision surface 51 projected onto a plane passing through the axis of the rotation shaft 58 is defined as the effective area of ​​the collision surface 51. This may be considered to be the area of ​​the collision surface 51 shown in FIG. 3(b).

[0046] When the inner radius of the mixing vessel 20 is R, the collision plate 50 is preferably located within 0.5R above the agitating blade 40 and within 0.5R from the body wall surface 23. In addition, the effective area is 0.05R. 2 -0.20R 2 It is preferable that the ratio is 0.1R 2 -0.15R 2 It is more preferable that:

[0047] 4 illustrates the cross-sectional shape and rotation direction of the scooping surface 61 of the scraper 60. Here, too, the rotation direction of the agitator blade 40 is assumed to be counterclockwise. When the scooping surface 61 rotates toward the circulating flow, the scooping surface 61 not only scoops up the deposits but also guides the circulating flow to stabilize it. When the scooping surface 61 rotates in the same direction as the circulating flow, it does not function as a guide and only scoops up the deposits.

[0048] 4(a) shows a scraper 60a with a flat scooping surface 61a, which moves toward the circulating flow. In this example, the scooping surface 61a is considered to act in the same manner as the collision plate 50 in the portion close to the lower collision plate 50.

[0049] The scraper 60b in FIG. 4(b) has a scooping surface 61b formed as a concave surface, and therefore is considered to have a stronger role as a guide for the circulating flow and a weaker role as a collision plate compared to the scraper 60a in FIG. 4(a).

[0050] The scraper 60c in Fig. 4(c) has two scooping surfaces 61c formed on concave surfaces and can reciprocate. When the scraper 60c rotates clockwise, the scooping surface 61c in the moving direction works in the same way as the scooping surface 61b in Fig. 4(b), but the other scooping surface 61c hardly functions at all. When the scraper 60c rotates counterclockwise, the scooping surface 61c in the moving direction removes deposits, and the other scooping surface 61c functions as a guide for the circulating flow.

[0051] 5 is an explanatory diagram illustrating a drive mechanism for reciprocating the collision plate 50 as a rotation mechanism for the collision plate 50. In this rotation mechanism, a case where an air cylinder 80 is used for driving will be described. Fig. 5(a) is a schematic plan view, and Fig. 5(b) is a schematic elevation view.

[0052] When driven by the reciprocating motion of the air cylinder 80, the angular range of the collision plate 50 is limited to about 90 degrees, but the object of the present invention can be achieved regardless of the number of collision plates 50. This is because it becomes possible to alternate between the vicinity of the upper part of the collision plate 50 and other areas shown in Fig. 3. However, if scrapers 60 are required, four or more scrapers 60 must be provided in order to remove fine powder from the entire circumference.

[0053] A rotating shaft 70 of the rotating mechanism is inserted into a sliding bearing 71 provided in the center of the lid 25 and is formed to be freely rotatable. A driving member 72 equipped with a driving lever 73 is fixed to the rotating shaft 70.

[0054] For example, PTFE (polytetrafluoroethylene) can be used as the material of the plain bearing 71. This allows the outer circumferential surface of the rotating shaft 70 to slide against the inner circumferential surface of the plain bearing 71, and the lower surface of the driving member 72 to slide against the upper surface of the plain bearing 71.

[0055] Since the rod 81 of the air cylinder 80 is connected to the driving member 72, the rotating shaft 70 can be rotated within a certain angular range by reciprocating the rod 81. In other words, the rotating shaft 70 can be repeatedly rotated in a clockwise direction and a counterclockwise direction within this angular range.

[0056] Next, the operation of the processing apparatus 10 of this embodiment will be described. The processing apparatus 10 of this embodiment thus configured can rotate the collision plate 50 along the body wall surface 23 of the mixing tank 20 during processing, thereby changing the state of the body wall surface 23 adjacent to the collision plate 50. That is, the moving collision plate 50 can immediately change the area of ​​the body wall surface 23 where adhesion is likely to occur into a body wall surface 23 with a cleaning effect. Therefore, in the vicinity of the area where the collision plate 50 rotates, the state where adhesion is likely to occur is no longer sustained over the entire circumference of the body wall surface 23, making it possible to prevent adhesion and deposition.

[0057] In addition, by utilizing a rotating mechanism for rotating the collision plate 50, a scraper 60 that rotates along the body wall surface 23 can be added as a component. This makes it possible to completely remove even the finest deposits not only from the vicinity of the area where the collision plate 50 rotates, but also over the wide body wall surface 23.

[0058] Although an embodiment of the present invention has been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment, and design changes that do not deviate from the gist of the present invention are included in the present invention.

[0059] For example, in the above embodiment, the case where an electric motor 90 is used to rotate the collision plate 50 in one direction in the processing device 10 has been described, but this is not limited to this, and the operation of repeatedly rotating in one direction and stopping can also be performed by combining a one-way clutch or the like with an air cylinder. [Explanation of symbols]

[0060] 10: Processing device 20: Mixing tank 23: Body wall 30: Rotation axis 40: Stirring blade 50: Collision plate 60: Scraper

Claims

1. A processing device for performing a process of colliding powder or granular material to be processed, A vertical mixing tank; A rotating shaft is inserted through the bottom of the mixing vessel; A plurality of stirring blades provided on the rotating shaft; An impingement plate disposed above the stirring blade; The treatment apparatus according to claim 1, wherein the collision plate is capable of rotating along a body wall surface of the mixing vessel during treatment.

2. 2. The processing apparatus according to claim 1, further comprising a scraper formed above said collision plate and rotating together with said collision plate.

3. 3. The processing apparatus according to claim 1, wherein the collision plate rotates in one direction, or rotates in one direction and then stops.

4. 3. The processing apparatus according to claim 1, wherein the collision plate rotates back and forth within a predetermined angle range, or rotates back and forth and then stops.

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