Crystallization apparatus, crystallization system, and crystallization method

Abstract

A crystallization device (4) comprises: a stirring blade (W) which is provided with a plurality of radially penetrating holes (h) and which is rotatable around a rotary shaft (3); a bottomed cylindrical reaction tank (1) capable of concentrically accommodating the stirring blade (W) therein; a first liquid supply part (5a) which is provided to the reaction tank (1) and which is capable of supplying a first reaction liquid (L1) into the reaction tank (1); and a second liquid supply part (5b) which is provided to the stirring blade (W) and which is capable of supplying a second reaction liquid (L2).

Description

Technical Field

[0001] The present invention relates to a crystallization apparatus, a crystallization system, and a crystallization method. This application claims priority based on Japanese Patent Application No. 2021-052574 filed in Japan on March 26, 2021, and incorporates the content herein.

Background Art

[0002] As crystallization apparatuses for mixing a plurality of raw material solutions and obtaining particles derived from the raw materials in the raw material solutions, the crystallization apparatuses described in Patent Documents 1 to 4 are known.

[0003] In the crystallization apparatus as described above, stirring is promoted by rotating a stirring blade provided in a mixture of a plurality of raw material solutions and applying a shearing force to the mixture. In order to produce finer particles with more uniform particle diameters and higher quality, it is important to efficiently transmit the shearing force generated by rotating the stirring blade at high speed to the reaction field, which is a field where a reaction occurs in which the plurality of raw material solutions come into contact with each other and particles are generated, to promote the reaction. In order to achieve efficient transmission of the shearing force, attempts have been made to minimize the clearance between the stirring blade, which is a rotor, and the reaction tank, the reaction liquid supply nozzle, etc., which are stators.

[0004] However, as the rotation speed of the stirring blade increases, it becomes more difficult and challenging from the perspective of manufacturing accuracy to minimize the clearance between the stirring blade and the reaction tank or between the stirring blade and the reaction liquid supply nozzle when manufacturing an apparatus on an industrial scale.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Patent Document 3

[0006] The present invention is made against this background and aims to provide a crystallization apparatus, crystallization system, and crystallization method that can minimize the clearance between the stirring blade and the reaction liquid supply nozzle without requiring high manufacturing precision, and that can set the reaction start point to a range within a very short distance, for example, 2 mm, from the inner and outer circumference of the stirring blade where the shear force is highest. [Means for solving the problem]

[0007] To solve the above problems and achieve these objectives, the present invention proposes the following means. A first aspect of the present invention is a crystallization apparatus comprising: a stirring blade having a plurality of radially penetrating holes and rotatable about a central axis; a bottomed cylindrical reaction vessel capable of concentrically housing the stirring blade; a first liquid supply unit provided in the reaction vessel and capable of supplying a first reaction liquid to the inside of the reaction vessel; and a second liquid supply unit provided on the stirring blade and capable of supplying a second reaction liquid to the inside of the reaction vessel.

[0008] According to the first aspect of the present invention, since the second reaction liquid is supplied from a second liquid supply section provided on the stirring blade, it is not necessary to require the high manufacturing precision required when the reaction liquid supply nozzle and the stirring blade are provided separately, and the second reaction liquid can be supplied to a range of close proximity, for example, within 2 mm, from the inner and outer circumference of the stirring blade where the shear force is highest. Furthermore, since the stirring blade has multiple holes that penetrate radially, the mixture of the first and second reaction liquids reacts as it moves towards the outer circumference of the stirring blade by passing through the holes toward the radially outward direction of the stirring blade due to the influence of centrifugal force, thereby further promoting the stirring of the mixture within a range of close proximity, for example, within 2 mm, from the inner and outer circumference of the stirring blade where the shear force is highest.

[0009] A second aspect of the present invention, in the first aspect, comprises a cylindrical portion, a disc-shaped portion whose outer edge is fixed to the inner circumferential surface of the cylindrical portion, and a rotating shaft extending upward along the central axis from the center of the disc portion in a plan view, wherein the second reaction liquid can flow through the interior of the disc portion and the rotating shaft, and the second liquid supply portion is provided on the outer edge of the disc portion.

[0010] According to a second aspect of the present invention, since a second liquid supply section is provided on the outer edge of the disc section, the second reaction solution can be supplied to a range of close proximity, for example, within 2 mm, from the inner and outer circumference of the stirring blade where the shear force is highest.

[0011] A third aspect of the present invention is characterized in that, in the second aspect, the second liquid supply section is open downward.

[0012] According to a third aspect of the present invention, since the second liquid supply section is open downward, the second reaction solution can be supplied to a very close range, for example, within 2 mm, from the inner and outer circumference of the stirring blade where the shear force is highest.

[0013] A fourth aspect of the present invention is characterized in that, in the second aspect, the second liquid supply portion opens radially outward and penetrates the cylindrical portion.

[0014] According to a fourth aspect of the present invention, since the second liquid supply section opens radially outward and penetrates the cylindrical section, the second reaction liquid can be supplied to a range of close proximity, for example, within 2 mm, from the inner and outer circumference of the stirring blade where the shear force is highest.

[0015] A fifth aspect of the present invention is characterized in that, in the third or fourth aspect, a plurality of holes penetrating in the radial direction are closed in the cylindrical portion above the disc portion, and a disc-shaped second disc portion is provided at the upper end of the cylindrical portion, the outer edge of which is fixed to the inner circumferential surface of the cylindrical portion.

[0016] According to the fifth aspect of the present invention, the second reaction liquid supplied from the second liquid supply unit can be supplied to a range within a closest distance, for example, within 2 mm, from the inner and outer circumferences of the stirring blade where the shearing force is the highest, and since the resistance force when the stirring blade rotates can be reduced, the power for rotating the stirring blade can be reduced.

[0017] The sixth aspect of the present invention is characterized in that, in the third aspect, the disk portion is provided at the upper end portion of the cylindrical portion.

[0018] According to the sixth aspect of the present invention, since the disk portion is provided at the upper end portion of the cylindrical portion, the second reaction liquid supplied from the second liquid supply unit can be supplied to a range within a closest distance, for example, within 2 mm, from the inner and outer circumferences of the stirring blade where the shearing force is the highest, and since the stirring blade is not provided above the disk portion, a stirring blade having a lightweight and simple structure can be obtained.

[0019] The seventh aspect of the present invention is characterized in that, in any one of the first to sixth aspects, the peripheral speed of the stirring blade is 5 m / s or more and 50 m / s or less.

[0020] According to the seventh aspect of the present invention, since the peripheral speed of the stirring blade is 5 m / s or more and 50 m / s or less, sufficient shearing force can be applied to the mixed liquid of the first reaction liquid and the second reaction liquid.

[0021] The eighth aspect of the present invention is characterized in that, in any one of the second to seventh aspects, when the clearance between the outer peripheral surface of the cylindrical portion and the inner peripheral surface of the reaction tank is L3 and the height of the cylindrical portion is H, H / L3 is 10 or more.

[0022] According to the eighth aspect of the present invention, since the clearance between the outer peripheral surface of the stirring blade and the inner peripheral surface of the reaction tank is set within a range where the manufacturing difficulty does not become excessively high with respect to the size of the stirring blade, when manufacturing an industrial-scale apparatus, a range within a closest distance (for example, within 2 mm) from the inner and outer circumferences of the stirring blade where the shearing force is the highest can be set as the reaction start point where the reaction between the first reaction liquid and the second reaction liquid starts.

[0023] According to a ninth aspect of the present invention, in any one of the first to eighth aspects, a plurality of the second liquid supply portions are provided.

[0024] According to the ninth aspect of the present invention, since a plurality of the second liquid supply portions are provided, the mixing of the second reaction liquid with the first reaction liquid can be performed more quickly than in the case where only one second liquid supply portion is provided.

[0025] According to a tenth aspect of the present invention, in the first aspect, the stirring blade includes a columnar cylindrical portion, a disk-shaped base portion provided concentrically with the cylindrical portion at an upper end portion of the cylindrical portion, a rotating shaft extending upward along the central axis from the center in a plan view of the disk-shaped base portion, and a cylindrical porous plate provided concentrically with the cylindrical portion on an outer side in a radial direction of the cylindrical portion. The porous plate extends downward from an outer edge of the disk-shaped base portion, the second reaction liquid can flow through an inside of the rotating shaft, the disk-shaped base portion, and the cylindrical portion, and a plurality of the second liquid supply portions are provided at intervals in a vertical direction on an outer peripheral surface of the cylindrical portion.

[0026] According to the tenth aspect of the present invention, the second reaction liquid can be supplied to a range closest to the inner and outer circumferences of the stirring blade where the shearing force is the highest, for example, within 2 mm, and since a plurality of the second liquid supply portions are provided at intervals in the vertical direction, the first reaction liquid and the second reaction liquid can be mixed more uniformly, and the influence of the shearing force can be applied to more locations, so that uniform and fine particles can be produced.

[0027] According to an eleventh aspect of the present invention, in the first aspect, the stirring blade includes a columnar cylindrical portion, a rotating shaft extending upward along the central axis from the center in a plan view of the cylindrical portion, and a cylindrical porous plate provided concentrically with the cylindrical portion on an outer side in a radial direction of the cylindrical portion. The porous plate is fixed to a connecting rod extending radially outward from an outer peripheral surface of the cylindrical portion, the second reaction liquid can flow through an inside of the rotating shaft and the cylindrical portion, and a plurality of the second liquid supply portions are provided at intervals in a vertical direction on an outer peripheral surface of the cylindrical portion.

[0028] According to the eleventh aspect of the present invention, the second reaction solution can be supplied to a range of close proximity, for example, within 2 mm, from the inner and outer circumference of the stirring blade where the shear force is highest, and since multiple second liquid supply sections are provided spaced apart in the vertical direction, the first reaction solution and the second reaction solution can be mixed more uniformly, and the effect of the shear force can be applied to more locations, thereby enabling the production of uniform and fine particles.

[0029] A twelfth aspect of the present invention is characterized in that, in the tenth or eleventh aspect, extension pipes are provided that extend radially outward from the plurality of second liquid supply sections.

[0030] According to a twelfth aspect of the present invention, the second reaction solution can be supplied to a range of close proximity, for example, within 2 mm, from the inner and outer circumference of the stirring blade where the shear force is highest, and the gap between the outer surface of the cylindrical part and the inner surface of the perforated plate can be widened, thereby promoting the circulation of the reaction solution.

[0031] A thirteenth aspect of the present invention is a crystallization system characterized by comprising a crystallization apparatus according to any one of the first to twelfth aspects, a retention tank for retaining the product transferred from the reaction vessel, and a circulation pump for circulating the product between the retention tank and the crystallization apparatus.

[0032] According to the thirteenth aspect of the present invention, a crystallization system can be obtained that can achieve the technical effects of any one of the first to twelfth aspects of the crystallization apparatus.

[0033] A fourteenth aspect of the present invention is a crystallization apparatus for obtaining a product by mixing two or more liquids, comprising: a stirring blade having a plurality of holes penetrating in the radial direction and rotating about a central axis; a bottomed cylindrical reaction vessel concentrically housing the stirring blade; a first liquid supply unit for supplying a first reaction liquid to the inside of the reaction vessel; and a second liquid supply unit provided on the stirring blade and capable of supplying a second reaction liquid, wherein the crystallization apparatus comprises a first liquid supply step of supplying the first reaction liquid from the first liquid supply unit to the reaction vessel; and a second liquid supply step of supplying the second reaction liquid from the second liquid supply unit to the reaction vessel 1.

[0034] According to the 14th aspect of the present invention, since the second reaction liquid is supplied from a second liquid supply section provided on the stirring blade, it is not necessary to require the high manufacturing precision required when the reaction liquid supply nozzle and the stirring blade are provided separately, and the second reaction liquid can be supplied to a range of close proximity, for example, within 2 mm, from the inner and outer circumference of the stirring blade where the shear force is highest. Furthermore, since the stirring blade has multiple holes that penetrate radially, the mixture of the first and second reaction liquids reacts as it moves towards the outer circumference of the stirring blade by passing through the holes toward the radially outward direction of the stirring blade due to the influence of centrifugal force, thereby further promoting the stirring of the mixture within a range of close proximity, for example, within 2 mm, from the inner and outer circumference of the stirring blade where the shear force is highest.

[0035] A fifteenth aspect of the present invention, in the fourteenth aspect, further comprises a cylindrical portion, a disc-shaped portion whose outer edge is fixed to the inner circumferential surface of the cylindrical portion, and a rotating shaft extending upward along the central axis from the center of the disc portion in a plan view, wherein the second reaction liquid can flow through the interior of the disc portion and the rotating shaft, and in the second liquid supply step, the second reaction liquid is supplied downward from the outer edge of the disc portion.

[0036] According to the 15th aspect of the present invention, since the second reaction liquid is supplied downward from the outer edge of the disc portion, the second reaction liquid can be supplied to a very close range, for example, within 2 mm, from the inner and outer circumference of the stirring blade where the shear force is highest.

[0037] A sixteenth aspect of the present invention, in the fourteenth aspect, further comprises a cylindrical portion, a disc-shaped portion whose outer edge is fixed to the inner circumferential surface of the cylindrical portion, and a rotating shaft extending upward along the central axis from the center of the disc portion in a plan view, wherein the second reaction liquid can flow through the interior of the disc portion and the rotating shaft, and in the second liquid supply step, the second reaction liquid is supplied radially outward from the outer edge of the disc portion through the cylindrical portion.

[0038] According to the sixteenth aspect of the present invention, since the second reaction liquid is supplied radially outward from the outer edge of the disc portion through the cylindrical portion, the second reaction liquid can be supplied to a very close distance, for example, within 2 mm, from the inner and outer circumference of the stirring blade where the shear force is highest.

[0039] A 17th aspect of the present invention, in the 14th aspect, comprises a cylindrical portion, a disc base provided concentrically with the cylindrical portion at the upper end of the cylindrical portion, a rotating shaft extending upward along the central axis from the center of the disc base in a plan view, and a cylindrical perforated plate provided concentrically with the cylindrical portion on the radially outer side of the cylindrical portion, wherein the perforated plate extends downward from the outer edge of the disc base, the second reaction liquid can flow through the interior of the rotating shaft, the disc base, and the cylindrical portion, and in the second liquid supply step, the second reaction liquid is supplied radially outward from a plurality of second liquid supply sections provided at vertical intervals on the outer circumferential surface of the cylindrical portion.

[0040] According to the 17th aspect of the present invention, the second reaction solution supplied from the second liquid supply unit can be supplied to a range of close proximity, for example, within 2 mm, from the inner and outer circumference of the stirring blade where the shear force is highest, and the first reaction solution and the second reaction solution can be mixed more uniformly, and the effect of the shear force can be applied to more locations, so that uniform and fine particles can be produced.

[0041] An eighteenth aspect of the present invention, in the fourteenth aspect, comprises a cylindrical portion, a rotating shaft extending upward along the central axis from the center of the cylindrical portion in a plan view, and a cylindrical porous plate provided concentrically with the cylindrical portion on the radially outer side of the cylindrical portion, wherein the porous plate is fixed to a connecting rod extending radially outward from the outer circumferential surface of the cylindrical portion, the second reaction liquid can flow through the interior of the rotating shaft and the cylindrical portion, and in the second liquid supply step, the second reaction liquid is supplied radially outward from a plurality of second liquid supply sections provided at vertical intervals on the outer circumferential surface of the cylindrical portion.

[0042] According to the 18th aspect of the present invention, the second reaction solution supplied from the second liquid supply unit can be supplied to a range of close proximity, for example, within 2 mm, from the inner and outer circumference of the stirring blade where the shear force is highest, and the first reaction solution and the second reaction solution can be mixed more uniformly, and the effect of the shear force can be applied to more locations, so that uniform and fine particles can be produced. [Effects of the Invention]

[0043] According to embodiments of the present invention, it is possible to obtain a crystallization apparatus, crystallization system, and crystallization method in which the clearance between the stirring blade and the reaction liquid supply nozzle can be minimized without requiring high manufacturing precision, and the reaction start point can be set to a range within a very short distance, for example, 2 mm, from the inner and outer circumference of the stirring blade where the shear force is highest. [Brief explanation of the drawing]

[0044] [Figure 1] This is a longitudinal cross-sectional view of a crystallization apparatus according to the first embodiment of the present invention. [Figure 2A] This is a longitudinal cross-sectional view of a schematic diagram showing the stirring blade of a crystallization apparatus according to the first embodiment of the present invention. [Figure 2B] This is a schematic plan view showing the stirring blade of a crystallization apparatus according to the first embodiment of the present invention. [Figure 3] This is a schematic diagram of a crystallization system including a crystallization apparatus according to a first embodiment of the present invention. [Figure 4] This is a schematic diagram showing a first modified example of the crystallization apparatus according to the first embodiment of the present invention. [Figure 5A] This is a front cross-sectional view of a schematic diagram of a main part showing a second modified example of the crystallization apparatus of the first embodiment according to the present invention. [Figure 5B] This is a top view of a schematic diagram of the main parts showing a second modified example of the crystallization apparatus of the first embodiment according to the present invention. [Figure 6A] This is a front cross-sectional view of a schematic diagram of a main part showing a third modified example of the crystallization apparatus of the first embodiment according to the present invention. [Figure 6B] This is a top view of a schematic diagram of the main parts showing a third modified example of the crystallization apparatus of the first embodiment according to the present invention. [Figure 7A] This is a front cross-sectional view of a schematic diagram of a main part showing a fourth modified example of the crystallization apparatus of the first embodiment according to the present invention. [Figure 7B] This is a top view of a schematic diagram of the main parts showing a fourth modified example of the crystallization apparatus of the first embodiment according to the present invention. [Figure 8A] This is a front cross-sectional view of a schematic diagram of the main part showing a fifth modified example of the crystallization apparatus of the first embodiment according to the present invention. [Figure 8B] This is a top view of a schematic diagram of the main parts showing a fifth modified example of the crystallization apparatus of the first embodiment according to the present invention. [Figure 9] This is a schematic diagram of the main parts showing a sixth modified example of the crystallization apparatus of the first embodiment according to the present invention. [Figure 10] This is a schematic diagram of the main parts showing a seventh modified example of the crystallization apparatus of the first embodiment according to the present invention. [Figure 11] This is a schematic diagram of the main parts showing an eighth modified example of the crystallization apparatus of the first embodiment according to the present invention. [Figure 12] This is a schematic diagram of the main parts showing a ninth modified example of the crystallization apparatus of the first embodiment according to the present invention. [Modes for carrying out the invention]

[0045] The crystallization apparatus 4 according to the first embodiment will be described below with reference to Figure 1. The crystallization apparatus 4 comprises a bottomed cylindrical reaction vessel 1 having a vertically oriented central axis O1, and a cylindrical stirring blade W. The stirring blade W is rotatable around a hollow rotating shaft 3 extending upward from the center of the stirring blade W in a plan view, and is housed inside the reaction vessel 1 with the central axis O1 as the same central axis. The rotating shaft 3 rotates due to rotational force supplied via a belt B from a prime mover M provided outside the crystallization apparatus 4. The prime mover M is not particularly limited as long as it is a device that generates rotational power, such as a motor or engine. The belt B that transmits the rotational force to the rotating shaft 3 is not particularly limited as long as it can transmit rotational force, such as a chain or gear. The bottom surface of the reaction vessel 1 may be a flat surface as shown in the figure, or it may be a cone shape that is convex downwards. An outlet 6 is provided at the top of the reaction vessel 1 to discharge the slurry containing particles (crystals) generated in the reaction vessel 1 to the next process. In the reaction vessel 1, a baffle 7 is provided above the stirring blade W to suppress the generation of vortices and promote stirring of the mixed liquid. The baffle 7 is constructed by attaching flat or cylindrical pipes at equal intervals. Note that the baffle 7 is provided only as needed, and therefore it is not necessary to provide it.

[0046] A first liquid supply section 5a is provided at the bottom of the reaction vessel 1, into which the first reaction solution L1 is supplied. The first reaction solution L1 is supplied to the reaction vessel 1 from the first liquid supply section 5a in a desired amount.

[0047] The stirring blade W of the crystallization apparatus 4 according to the first embodiment will be described below with reference to Figures 1, 2A, and 2B. The stirring blade W comprises a cylindrical section 2 and a disc-shaped section 8 whose outer edge is fixed to the inner circumferential surface 2i of the cylindrical section 2. The disc section 8 is positioned at approximately half the height of the cylindrical section 2, but is not limited to this example and may be positioned below or above approximately half the height of the cylindrical section 2. A rotating shaft 3 is fixed to the center of the disc section 8 in a plan view. The hollow interior of the rotating shaft 3 is a conduit P1. Multiple conduits P2 extend radially from the center toward the outer edge inside the disc section 8. The conduits P1 of the rotating shaft 3 and the conduits P2 of the disc section 8 are in communication. A second reaction liquid L2 is supplied to the rotating shaft 3 of the stirring blade W from a tank T located outside the crystallization apparatus 4. The second reaction liquid L2 is supplied to the hollow conduit P1 of the rotating shaft 3 via a rotary joint R, and then supplied to the conduits P2 of the disc section 8. The radially outer end of the pipeline P2 of the reaction vessel 1 opens downward and serves as a second liquid supply section 5b from which the second reaction liquid L2 is discharged. Therefore, multiple second liquid supply sections 5b are provided on the disc section 8 at intervals in the circumferential direction of the disc section. In the example shown in Figures 2A and 2B, eight second liquid supply sections 5b are provided as shown in Figure 2B. The number of second liquid supply sections 5b is not limited, but it is desirable to provide them symmetrically with respect to the central axis O1.

[0048] In this embodiment, the distance between the inner circumferential surface 2i of the cylindrical portion 2 of the stirring blade W and the center of the second liquid supply portion 5b is 2 mm or less. Furthermore, if L3 is the distance (clearance) between the outer circumferential surface 2o of the cylindrical portion 2 of the stirring blade W and the inner circumferential surface 1i of the reaction vessel 1, and H is the height along the central axis O1 of the stirring blade W (cylindrical portion 2), then it is preferable that the ratio of H to L3, H / L3, is 10 or more. It is even more preferable that H / L3 is 25 or more. Therefore, even when using equipment of a different size than that of this embodiment, a similar equipment can be manufactured based on this ratio. The stirring blade W rotates at a peripheral speed of 5 m / s or more and 50 m / s or less. Note that the H / L3 ratio may differ from the above ratio depending on the purpose. For example, if you want to suppress crystal fracture, you may lower the ratio from the value above.

[0049] The cylindrical portion 2 of the stirring blade W is provided with multiple holes h that penetrate the cylindrical portion 2 in the radial direction. These holes h allow the first reaction liquid L1, the second reaction liquid L2, or a mixture thereof to flow through. Therefore, the first reaction liquid L1, the second reaction liquid L2, or a mixture thereof can move from the inside to the outside of the stirring blade W, or from the outside to the inside of the stirring blade W, through the multiple holes h. In addition to the holes h, the disc portion 8 may also be provided with multiple holes 9 that penetrate in the direction of the central axis O1 (see Figures 5A and 5B described later). In this case, the first reaction liquid L1, the second reaction liquid L2, or a mixture thereof can move from the inside to the outside of the stirring blade W, or from the outside to the inside of the stirring blade W, through the holes 9 in addition to the multiple holes h.

[0050] In such a crystallization apparatus 4, a desired amount of the first reaction solution L1 is supplied to the reaction vessel 1 from the first liquid supply section 5a. The amount of the first reaction solution L1 supplied may be enough to fill the reaction vessel 1 (full volume), or it may be enough so that when the stirring blade W rotates, the first reaction solution L1 performs circular motion around the central axis O1 of the reaction vessel 1, and the centrifugal force generated in the first reaction solution L1 presses it against the inner surface 1i of the reaction vessel 1, forming a liquid film of the first reaction solution L1 on the inner surface 1i of the reaction vessel 1. By adjusting the opening of the opening adjustment valve V described later, the amount of the first reaction solution L1 supplied can be adjusted and the desired amount can be selected. In the following explanation, we will assume that the first reaction solution L1 is supplied to the point where the vessel is full. Alternatively, the reaction in the reaction vessel 1 may be carried out after supplying the first reaction solution L1 to the extent that it reaches the full liquid state or liquid film formation state described above, and then stopping the supply of the first reaction solution L1. Alternatively, the reaction in the reaction vessel 1 may be carried out continuously while maintaining the flow rate of the first reaction solution L1 at a level that reaches the full liquid state or liquid film formation state described above.

[0051] With the reaction vessel 1 filled with the first reaction liquid L1, the stirring blade W is rotated, and the second reaction liquid L2 is supplied into the reaction vessel 1 by discharging it from the second liquid supply section 5b along the inner circumferential surface 2i of the cylindrical section 2 of the stirring blade W. In this way, the second reaction liquid L2 discharged from the second liquid supply section 5b along the inner circumferential surface 2i of the cylindrical section 2 of the stirring blade W comes into contact with the first reaction liquid L1, which is rotating in conjunction with the rotation of the stirring blade W near the inner circumferential surface 2i of the cylindrical section 2 of the stirring blade W in the reaction vessel 1 filled with the first reaction liquid L1. A reaction occurs when the first reaction liquid L1 and the second reaction liquid L2 come into contact, and particles are generated.

[0052] In this process, the second reaction liquid L2 is supplied to the first reaction liquid L1 from the second liquid supply section 5b of the stirring blade W, which is rotating at a peripheral speed of 5 m / s to 50 m / s, thereby enabling uniform mixing of the second reaction liquid L2 with the first reaction liquid L1.

[0053] Here, the first reaction liquid L1, which rotates in conjunction with the rotation of the stirring blade W, and the second reaction liquid L2, which is discharged from the second liquid supply section 5b of the stirring blade W, which rotates at a peripheral speed of 5 m / s to 50 m / s, and the mixture thereof (hereinafter sometimes collectively referred to as the mixture) move radially outward from the cylindrical portion 2 of the stirring blade W, pass through a plurality of holes h provided in the cylindrical portion 2 of the stirring blade W, and collide with the inner circumferential surface 1i of the reaction tank 1, and then move vertically along the inner circumferential surface 1i of the reaction tank 1. The mixture, which mainly moves downward, is attracted by the radially outward flow caused by the centrifugal force generated by the rotation of the stirring blade W, and again passes through a plurality of holes h provided in the cylindrical portion 2 of the stirring blade W, colliding with the inner circumferential surface 1i of the reaction tank 1, and then moves vertically along the inner circumferential surface 1i of the reaction tank 1, thereby creating convection. Here, as the mixed liquid passes through multiple holes h, the effect of the throttling channel accelerates the mixed liquid radially outward, so the radially outward flow velocity of the mixed liquid is highest near the multiple holes h. Furthermore, a shear force is applied in the circumferential direction to the mixed liquid present between the outer circumferential surface 2o and inner circumferential surface 2i of the cylindrical portion 2 of the stirring blade W, which rotates at a peripheral speed of 5 m / s to 50 m / s, and the inner circumferential surface 1i of the reaction vessel 1 which is fixed to it. The shear force applied to the mixed liquid is greater the closer it is to the inner circumferential surface 2i and outer circumferential surface 2o of the cylindrical portion 2 of the stirring blade W. The shear force applied to the mixed liquid is a major factor in determining the particle size and uniformity of the resulting particles. In particular, the larger the applied shear force, the finer the particle size of the resulting particles can be obtained.

[0054] In the crystallization apparatus 4 of this embodiment, the second liquid supply section 5b is provided on the outer edge of the disc section 8. Specifically, as described above, the distance between the inner circumferential surface 2i of the cylindrical section 2 of the stirring blade W and the center of the second liquid supply section 5b is 2 mm or less. Therefore, at the reaction initiation point where the second reaction liquid L2 discharged from the second liquid supply section 5b along the inner circumferential surface 2i of the cylindrical section 2 of the stirring blade W and the first reaction liquid L1 rotating near the inner circumferential surface 2i of the cylindrical section 2 of the stirring blade W in conjunction with the rotation of the stirring blade W first come into contact and begin to react, a maximum amount of shear force is applied in addition to the flow directed radially outward due to centrifugal force and the effect of the throttling channel. Therefore, the region where the applied shear force is greatest can be designated as the reaction initiation point. Specifically, the reaction initiation point can be formed in a region at a very close distance, for example, within 2 mm, from the inner circumferential surface 2i and outer circumferential surface 2o of the cylindrical section 2 of the stirring blade W. Here, the mixed liquid can move from the inner circumference to the outer circumference of the cylindrical part 2 through the multiple holes h mentioned above. Therefore, stirring of the first reaction liquid L1 and the second reaction liquid L2 at the reaction initiation point is promoted by shear force. As a result, a more uniform mixing of the first reaction liquid L1 and the second reaction liquid L2 begins from the reaction initiation point, and mixing and reaction occur in the reaction field, which is the field where the reaction takes place along the flow of the mixed liquid, thereby producing particles with fine and uniform diameters. The baffle 7 has the effect of suppressing the generation of vortices and promoting stirring of the mixed liquid when the reaction tank 1 is full of liquid. On the other hand, when the reaction tank 1 is not full of liquid and a liquid film of the mixed liquid is formed, it is not necessary to provide the baffle 7. Here, the reaction initiation point refers to the region where the reaction starts, and the reaction field refers to the entire field where the reaction takes place. Therefore, the reaction initiation point is included in the reaction field. Note that baffle 7 is not a mandatory component and does not need to be provided. For example, if a mechanical seal (not shown) is provided at the location where the rotating shaft 3 is inserted in the reaction vessel 1, and a completely liquid state without a gas phase is achieved, the generation of vortices is suppressed, and baffle 7 does not need to be provided. If baffle 7 is not provided, the flow resistance is reduced, and the power of the prime mover M can be reduced.

[0055] Furthermore, the same effect can be obtained even when a liquid film is formed rather than when the liquid is completely full, as in the case of a completely full liquid state.

[0056] Figure 3 is a schematic diagram of a crystallization system S equipped with a crystallization apparatus 4 according to the first embodiment. The crystallization system S of the crystallization apparatus 4 includes a retention tank 10 downstream of the crystallization apparatus 4, to which slurry D1 containing particles generated in the crystallization apparatus 4 is transferred. An outlet for discharging slurry D1 is provided at the top of the retention tank 10, and the first stock solution S3 of the first reaction liquid L1 is supplied to the retention tank 10 from a tank not shown. The retention tank 10 is provided with a pipeline for discharging a mixture of the first stock solution S3 and slurry D1 to the outside, and this pipeline is connected to the crystallization apparatus 4 via a circulation pump P. Between the retention tank 10 and the crystallization apparatus 4, a second stock solution S2 of the first reaction liquid L1 may be supplied upstream of the circulation pump P as needed, or residual slurry D2 may be further discharged downstream of the circulation pump P. Here, the circulation rate of the mixture of the first stock solution S3 and slurry D1 is adjusted by changing the rotation speed of the circulation pump P or by adjusting the opening of a circulation rate control valve (not shown) installed downstream of the circulation pump P. The residence time of the mixture in the retention tank 10 is adjusted by changing the liquid level of the slurry held in the retention tank 10. The liquid level of the slurry in the retention tank 10 is adjusted by selecting and using one of the numerous slurry D1 outlets (only one shown) installed at different heights on the side of the retention tank 10, or by automatically adjusting the flow rate of residual slurry D2 discharged from downstream of the circulation pump P to the outside of the crystallization system S by adjusting the opening of an automatic valve V2 attached to the outlet so that the value of the level meter Lv1 that detects the level in the retention tank 10 becomes a predetermined value.

[0057] With a crystallization system S including such a crystallization apparatus 4, the shear force affecting particle quality such as particle size, particle size distribution, and sphericity of the reaction product in the crystallization apparatus 4, the circulation rate of the first reaction solution L1, and the residence time of the slurry can be individually adjusted, thereby further improving the control performance of particle quality.

[0058] Figure 4 is a schematic diagram showing a first modified example of the crystallization apparatus 4 of the first embodiment. In this crystallization apparatus 4a, an opening adjustment valve V is provided at the outlet 6. By adjusting the opening of this opening adjustment valve V, the reaction vessel 1 can be selected to either be in a full-liquid state or a liquid film state in which a liquid film is formed.

[0059] Figures 5A and 5B are schematic diagrams of the main parts showing a second modified example of the crystallization apparatus 4 of the first embodiment. The difference in the second modified example is that the stirring blade W of the crystallization apparatus 4 of the first embodiment is replaced with a stirring blade Wa. In the following description, only the differences from the stirring blade W will be explained, and the explanation of overlapping parts will be omitted. As shown in Figure 5A, the stirring blade Wa differs from the stirring blade W in that the second liquid supply section 5b, located on the outer edge of the disc section 8, penetrates the cylindrical section 2 and opens radially outward. In such a stirring blade Wa, the second reaction liquid L2 is discharged from the second liquid supply section 5b that opens radially outward, resulting in high radial (horizontal) dispersibility of the second reaction liquid L2 and the mixture of the first reaction liquid L1 and the second reaction liquid L2. Using a crystallization apparatus 4 equipped with such a stirring blade Wa can achieve the same effects as a crystallization apparatus 4 equipped with a stirring blade W. In the examples of Figures 5A and 5B, as shown in Figure 5B, multiple holes 9 are provided in the disc section 8 that penetrate in the direction of the central axis O1, but multiple holes 9 are not required. If multiple holes 9 are provided, it is preferable to provide them symmetrically with respect to the center of the disc section 8. When multiple holes 9 are provided, the number of holes 9 is not limited to the 8 shown in Figure 5B. Here, the multiple holes 9 have the effect of reducing the power load on the stirring blade W by allowing a portion of the mixture to flow between the lower and upper sides of the stirring blade W through the multiple holes 9. However, since the mixture that has passed through the multiple holes 9 bypasses the reaction field around the stirring blade W and takes a short pass through it, the effect of producing uniform and fine particles is reduced compared to when the multiple holes 9 are not provided. Therefore, the application of the holes 9 can be selected considering the desired particle quality and the required power.

[0060] Figures 6A and 6B are schematic diagrams of the main parts showing a third modified example of the crystallization apparatus 4 of the first embodiment. The difference in the third modified example is that the stirring blade Wa in the second modified example of the crystallization apparatus 4 of the first embodiment is replaced by the stirring blade Wb. In the following description, only the differences from the stirring blade Wa will be explained, and the explanation of overlapping parts will be omitted. As shown in Figure 6A, the stirring blade Wb has multiple radially penetrating holes h in the cylindrical portion 2 above the disc portion 8 of the stirring blade Wa, and a second disc portion 15 is provided at the upper end of the cylindrical portion 2, with its outer edge fixed to the inner circumferential surface 2i of the cylindrical portion 8. The second disc portion 15 is a disc-shaped member and has a hole through its center through which the rotating shaft 3 passes. Except for the hole through which the rotating shaft 3 passes, there are no holes penetrating the second disc portion 15 in the direction of the central axis O1. Therefore, the first reaction liquid L1, the second reaction liquid L2, and their mixture do not enter the inside of the second disc portion 15. In this type of stirring blade Wb, there are no multiple holes h that penetrate radially through the cylindrical portion 2 above the disc portion 8, and a second disc portion 15, whose outer edge is fixed to the inner circumferential surface 2i of the cylindrical portion 8, is provided at the upper end of the cylindrical portion 2. As a result, the resistance force of the stirring blade Wb when it rotates is reduced, and the stirring blade Wb can be operated with less power than the stirring blade Wa.

[0061] Figures 7A and 7B are schematic diagrams of the main parts showing a fourth modified example of the crystallization apparatus 4 of the first embodiment. The difference in the fourth modified example is that the stirring blade W of the crystallization apparatus 4 of the first embodiment is replaced with a stirring blade Wc. In the following description, only the differences from the stirring blade W will be explained, and the explanation of overlapping parts will be omitted. As shown in Figure 7A, the stirring blade Wc has multiple radially penetrating holes h in the cylindrical portion 2 above the disc portion 8, which are closed. Additionally, a second disc portion 15 is provided at the upper end of the cylindrical portion 2, with its outer edge fixed to the inner circumferential surface 2i of the cylindrical portion 8. The second disc portion 15 is a disc-shaped member with a hole through its center through which the rotating shaft 3 passes. Aside from the hole through which the rotating shaft 3 passes, there are no holes penetrating the second disc portion 15 in the direction of the central axis O1. Therefore, the first reaction liquid L1, the second reaction liquid L2, and their mixture cannot enter the inside of the second disc portion 15. In this type of stirring blade Wc, there are no multiple holes h that penetrate radially through the cylindrical portion 2 above the disc portion 8, and a second disc portion 15, whose outer edge is fixed to the inner circumferential surface 2i of the cylindrical portion 8, is provided at the upper end of the cylindrical portion 2. As a result, the resistance force of the stirring blade Wc when it rotates is reduced. Therefore, the stirring blade Wc can be operated with less power than a conventional stirring blade W.

[0062] Figures 8A and 8B are schematic diagrams of the main parts showing a fifth modified example of the crystallization apparatus 4 of the first embodiment. The difference in the fifth modified example is that the stirring blade W of the crystallization apparatus 4 of the first embodiment is replaced with a stirring blade Wd. In the following description, only the differences from the stirring blade W will be explained, and the explanation of overlapping parts will be omitted. As shown in Figure 8A, the stirring blade Wd differs from the stirring blade W in that the disc portion 8 is located at the upper end of the cylindrical portion 2. Also, the height of the cylindrical portion 2 is about half the height of the cylindrical portion 2 of the stirring blade W. Using a crystallization apparatus 4 equipped with such a stirring blade Wd can achieve the same effects as a crystallization apparatus 4 equipped with a stirring blade W. Furthermore, since the cylindrical portion 2 is not located above the disc portion 8, the stirring blade Wd can be made lighter than the stirring blade W, and the stirring blade Wd can have a simpler structure. As a result, the stirring blade Wd can be operated with less power than the stirring blade W, which can lead to energy savings in the crystallization apparatus 4 and easier manufacturing of the stirring blade Wd. In addition, because the height of the cylindrical portion 2 is kept short, the crystallization apparatus 4 can be made smaller. Note that in the examples of Figures 8A and 8B, as shown in Figure 8B, the disc portion 8 does not have multiple holes 9 that penetrate in the direction of the central axis O1, but multiple holes 9 may be provided. In that case, the same effect as when the disc portion 8 of the stirring blade Wa is provided with multiple holes 9 that penetrate in the direction of the central axis O1 can be expected.

[0063] Figure 9 is a schematic diagram of the main parts showing a sixth modified example of the crystallization apparatus 4 of the first embodiment. The difference in the sixth modified example is that the stirring blade W of the crystallization apparatus 4 of the first embodiment is replaced with a stirring blade We. In the following description, only the differences from the stirring blade W will be explained, and the explanation of overlapping parts will be omitted. As shown in Figure 9, the stirring blade We comprises a cylindrical portion 20, a disc base 18 concentrically provided at the upper end of the cylindrical portion 20, a rotating shaft 3 extending upward along the central axis O1 from the center of the disc base 18 in a plan view, and a cylindrical perforated plate 18P concentrically provided on the radially outer side of the cylindrical portion 20. The perforated plate 18P is provided with a plurality of holes 18h that penetrate radially through the plate 18P, and the first reaction liquid L1, the second reaction liquid L2, and their mixture can flow through the plurality of holes 18h. The perforated plate 18P extends downward from the outer edge of the disc base 18. The second reaction liquid can flow through conduits P1, P2, and P3 provided inside the rotating shaft 3, the disc base 18, and the cylindrical portion 20, respectively. Pipelines P1, P2, and P3 are all connected to each other. Pipeline P2 extends radially outward from the lower end of pipeline P1, around the central axis O1. Pipeline P3 extends downward along the central axis O1 from the radially outer end of pipeline P2. Pipelines P2 and P3 are formed inside the cylindrical section 20. Multiple second liquid supply sections 50b are provided on the outer circumferential surface 20o of the cylindrical section 20 at vertical intervals. When the stirring blade We rotates, the rotation shaft 3, the disc base 18, the cylindrical section 20, and the perforated plate 18P rotate together as a single unit. In this type of stirring blade We, the second reaction liquid L2 is supplied into the reaction tank 1 from a plurality of second liquid supply sections 50b provided at vertical intervals on the outer circumferential surface 20o of the cylindrical section 20, and flows through a plurality of holes 18h of the perforated plate 18P while mixing and reacting with the first reaction liquid L1 in the reaction tank 1. As a result, the first reaction liquid L1 and the second reaction liquid L2 can be mixed more uniformly. The mixed liquid, having passed through the multiple holes 18h of the perforated plate 18P, collides with the inner circumference 1i of the reaction vessel 1 and then moves vertically along the inner surface 1i of the reaction vessel 1. The mixed liquid that has moved downward is attracted by the radially outward flow caused by the centrifugal force generated by the rotation of the stirring blade We, and again passes through the multiple holes 18h of the perforated plate 18P of the stirring blade We and collides with the inner surface 1i of the reaction vessel 1, and then moves vertically along the inner surface 1i of the reaction vessel 1, thereby creating convection. Here, as the mixed liquid passes through the multiple holes 18h, the mixed liquid is accelerated radially outward due to the effect of the throttling channel, so the radially outward flow velocity of the mixed liquid is highest near the multiple holes 18h. Furthermore, a shear force is applied in the circumferential direction to the mixed liquid between the outer circumferential surface 20o of the cylindrical portion 20 of the stirring blade We, which rotates at a peripheral speed of 5 m / s to 50 m / s, and the inner and outer circumferential surfaces of the perforated plate 18P, and the inner circumferential surface 1i of the fixed reaction vessel 1. The shear force applied to the mixed liquid is greater the closer it is to the outer circumferential surface 2o of the cylindrical portion 20 of the stirring blade We and the inner and outer circumferential surfaces of the perforated plate 18P. The shear force applied to the mixed liquid is a major factor in determining the particle size and uniformity of the resulting particles. In particular, the greater the shear force applied, the finer the particles that can be obtained. When using the stirring blade We, the influence of the shear force can be applied to more locations than when using the stirring blade W, so uniform and fine particles can be produced. The second reaction liquid L2 supplied from the second liquid supply section 50b can be supplied to the inner and outer circumference of the stirring blade We, which has the highest shear force, i.e., within a range of close proximity, for example, within 2 mm, from the outer surface 20o of the cylindrical section 20 and the inner and outer surfaces of the perforated plate 18P. In the example shown in Figure 9, four second liquid supply units 50b are provided in the vertical direction of the cylindrical unit 20. However, the number of second liquid supply units 50b is not limited to the example in Figure 9 and may be increased or decreased depending on the size of the reaction vessel 1.

[0064] Figure 10 is a schematic diagram of the main parts showing a seventh modified example of the crystallization apparatus 4 of the first embodiment. The seventh modified example differs from the crystallization apparatus 4 of the first embodiment in that the stirring blade W is replaced with a stirring blade Wf. In the following description, only the differences from the stirring blade W will be explained, and the explanation of overlapping parts will be omitted. As shown in Figure 10, the stirring blade Wf ​​comprises a cylindrical section 20, a rotating shaft 3 extending upward along the central axis O1 from the center of the cylindrical section 20 in a plan view, and a cylindrical perforated plate 18P provided concentrically with the cylindrical section 20 on the radially outer side of the cylindrical section 20. The perforated plate 18P is provided with a plurality of holes 18h that penetrate radially through the plate 18P, and the first reaction liquid L1, the second reaction liquid L2, and their mixture can flow through the plurality of holes 18h. The perforated plate 18P is fixed to a connecting rod 11 extending radially outward from the outer circumferential surface 2o of the cylindrical section 20. The second reaction liquid can flow through conduits P1, P2, and P3 provided inside the rotating shaft 3 and the cylindrical section 20, respectively. The conduits P1, P2, and P3 are all in communication with each other. Pipe P2 extends radially outward from the lower end of pipe P1, centered on the central axis O1. Pipe P3 extends downward along the central axis O1 from the radially outer end of pipe P2. Pipes P2 and P3 are formed inside the cylindrical section 20. Multiple second liquid supply sections 50b are provided on the outer circumferential surface 20o of the cylindrical section 20 at vertical intervals. When the stirring blade Wf ​​rotates, the rotation shaft 3, the cylindrical section 20, the connecting rods 11, and the perforated plate 18P rotate together. Multiple connecting rods 11 are provided at equal intervals around the circumference of the cylindrical section 20. It is preferable that two or more connecting rods 11 are provided. The connecting rods 11 are provided at approximately half the height of the cylindrical section 20, but this example is not limited to this, and they may be provided above or below approximately half the height of the cylindrical section 20. In this type of stirring blade Wf, the second reaction liquid L2 is supplied into the reaction tank 1 from a plurality of second liquid supply sections 50b provided at vertical intervals on the outer circumferential surface 20o of the cylindrical section 20, and flows through a plurality of holes 18h of the perforated plate 18P while mixing and reacting with the first reaction liquid L1 in the reaction tank 1. As a result, the first reaction liquid L1 and the second reaction liquid L2 can be mixed more uniformly. The mixed liquid, having passed through the multiple holes 18h of the perforated plate 18P, collides with the inner circumference 1i of the reaction vessel 1 and then moves vertically along the inner surface 1i of the reaction vessel 1. The mixed liquid, having moved vertically, is attracted by the radially outward flow caused by the centrifugal force generated by the rotation of the stirring blade Wf, and again passes through the multiple holes 18h of the perforated plate 18P of the stirring blade We and collides with the inner surface 1i of the reaction vessel 1. After that, it moves vertically along the inner surface 1i of the reaction vessel 1, creating convection. Here, as the mixed liquid passes through the multiple holes 18h, the mixed liquid is accelerated radially outward due to the effect of the throttling channel, so the radially outward flow velocity of the mixed liquid is highest near the multiple holes 18h. Furthermore, a shear force is applied in the circumferential direction to the mixed liquid between the outer circumferential surface 20o of the cylindrical portion 20 of the stirring blade Wf, which rotates at a peripheral speed of 5 m / s to 50 m / s, and the inner and outer circumferential surfaces of the perforated plate 18P, and the inner circumferential surface 1i of the fixed reaction vessel 1. The shear force applied to the mixed liquid is greater the closer it is to the outer circumferential surface 2o of the cylindrical portion 20 of the stirring blade Wf ​​and the inner and outer circumferential surfaces of the perforated plate 18P. The shear force applied to the mixed liquid is a major factor in determining the particle size and uniformity of the resulting particles. In particular, the greater the applied shear force, the finer the particles that can be obtained. When using the stirring blade Wf, the effect of the shear force can be applied to more locations, making it possible to produce uniform and fine particles. The second reaction liquid L2 supplied from the second liquid supply section 50b can be supplied to the inner and outer circumference of the stirring blade We, which has the highest shear force, i.e., within a range of close proximity, for example, within 2 mm, from the outer surface 20o of the cylindrical section 20 and the inner and outer surfaces of the perforated plate 18P. In the example shown in Figure 10, four second liquid supply units 50b are provided in the vertical direction of the cylindrical unit 20. However, the number of second liquid supply units 50b is not limited to the example shown in Figure 10 and may be increased or decreased depending on the size of the reaction vessel 1.

[0065] Figure 11 is a schematic diagram of the main parts showing the eighth modified example of the crystallization apparatus 4 of the first embodiment. The eighth modified example differs from the sixth modified example of the crystallization apparatus 4 of the first embodiment in that the stirring blade We is replaced by a stirring blade Wg. In the following description, only the differences from the stirring blade We will be explained, and the explanation of overlapping parts will be omitted. As shown in Figure 11, the stirring blade Wg has a wider gap between the outer surface 20o of the cylindrical portion 20 and the inner surface of the perforated plate 18P than the stirring blade We of the sixth modified example. In addition, an extension pipe 12 is provided that extends radially outward from the second liquid supply portion 50b of the stirring blade We, and the tip of the extension pipe 12 is the second liquid supply portion 50b. With such a stirring blade Wg, the gap between the outer surface 20o of the cylindrical portion 20 and the inner surface of the perforated plate 18P can be widened, making it easier for the first reaction liquid L1, the second reaction liquid L2, and their mixture to flow between the cylindrical portion 20 and the perforated plate 18P. Therefore, the circulation of the reaction liquid can be promoted, making it possible to produce uniform and fine particles. In addition, the second reaction liquid L2 supplied from the second liquid supply section 50b can be supplied to the inner and outer circumference of the stirring blade Wg, where the shear force is highest, i.e., within a very short distance from the inner and outer surfaces of the perforated plate 18P, for example, within 2 mm.

[0066] Figure 12 is a schematic diagram of the main parts showing the ninth modified example of the crystallization apparatus 4 of the first embodiment. The difference in the ninth modified example is that the stirring blade Wf ​​in the seventh modified example of the crystallization apparatus 4 of the first embodiment is a stirring blade Wh. In the following description, only the differences from the stirring blade Wf ​​will be explained, and the explanation of overlapping parts will be omitted. As shown in Figure 12, the stirring blade Wh has a wider gap between the outer surface 20o of the cylindrical portion 20 and the perforated plate 18P than the stirring blade Wf ​​of the seventh modified example. In addition, an extension pipe 12 is provided that extends radially outward from the second liquid supply portion 50b of the stirring blade Wf, which opens radially outward, and the tip of the extension pipe 12 is the second liquid supply portion 50b. With such a stirring blade Wh, the gap between the outer surface 20o of the cylindrical portion 20 and the inner surface of the perforated plate 18P can be widened, making it easier for the first reaction liquid L1, the second reaction liquid L2, and their mixture to flow between the cylindrical portion 20 and the perforated plate 18P. Therefore, the circulation of the reaction liquid can be promoted, making it possible to produce uniform and fine particles. In addition, the second reaction liquid L2 supplied from the second liquid supply section 50b can be supplied to the inner and outer circumference of the stirring blade Wg, which has the highest shear force, i.e., within a range of very close distance from the inner and outer surfaces of the perforated plate 18P, for example, within 2 mm. Among the above modified examples, the stirring blade W of the crystallization apparatus 4 according to the first embodiment, the stirring blade Wc according to the fourth modified example, and the stirring blade Wd according to the fifth modified example, in which the second liquid supply section 5b is open downwards, can mix the first reaction liquid L1 and the second reaction liquid L2 more uniformly.

[0067] Furthermore, generating particles using the crystallization apparatus described in the above embodiment can be considered as a crystallization method. For example, the crystallization apparatus 4 of the first embodiment can be considered as a crystallization method comprising: a cylindrical stirring blade W having a plurality of holes h penetrating in the radial direction and rotating around a central axis O1; a bottomed cylindrical reaction vessel 1 concentrically housing the stirring blade W; a first liquid supply unit 5a provided in the reaction vessel 1 and supplying a first reaction liquid L1 into the reaction vessel 1; and a second liquid supply unit 5b provided on the stirring blade W and capable of supplying a second reaction liquid L2 into the reaction vessel 1.

[0068] Furthermore, the crystallization apparatus 4 of the first embodiment can be considered as a crystallization method in which the stirring blade W further comprises a cylindrical cylindrical portion 2, a disc-shaped disc portion 8 whose outer edge is fixed to the inner circumferential surface 2i of the cylindrical portion 2, and a rotating shaft 3 extending upward along the central axis O1 from the center of the disc portion 8 in a plan view, and the second reaction liquid can flow through the inside of the disc portion 8 and the rotating shaft 3, and in the second liquid supply step, the second reaction liquid L2 is supplied downward from the outer edge of the disc portion 8. With such a crystallization method, the same effects as the crystallization apparatus 4 of the first embodiment can be obtained.

[0069] Furthermore, a second modification of the crystallization apparatus 4 of the first embodiment can be considered as a crystallization method in which the stirring blade Wa further comprises a cylindrical cylindrical portion 2, a disc-shaped disc portion 8 whose outer edge is fixed to the inner circumferential surface of the cylindrical portion 2, and a rotating shaft 3 extending upward along the central axis O1 from the center of the disc portion 8 in a plan view, the second reaction liquid L2 can flow through the inside of the disc portion 8 and the rotating shaft 3, and in the second liquid supply step, the second reaction liquid L2 is supplied radially outward from the outer edge of the disc portion 8 through the cylindrical portion. With such a crystallization method, the same effects as the crystallization apparatus 4 of the first embodiment can be obtained.

[0070] Furthermore, a sixth modification of the crystallization apparatus 4 of the first embodiment can be considered as a crystallization method in which the stirring blade We comprises a cylindrical portion 20, a disc base 18 provided concentrically with the cylindrical portion 20 at the upper end of the cylindrical portion 20, a rotating shaft 3 extending upward along the central axis O1 from the center of the disc base 18 in a plan view, and a cylindrical perforated plate 18P provided concentrically with the cylindrical portion 20 on the radially outer side of the cylindrical portion 20, wherein the perforated plate 18P extends downward from the outer edge of the disc base 18, and the second reaction liquid L2 can flow through the interior of the rotating shaft 3, the disc base 18, and the cylindrical portion 20, and in the second liquid supply step, the second reaction liquid L2 is supplied radially outward from a plurality of second liquid supply sections 50b provided at vertical intervals on the outer peripheral surface 20o of the cylindrical portion 20. This crystallization method allows for more uniform mixing of the first and second reaction solutions. Furthermore, the second reaction solution L2 can be supplied to the inner and outer circumference of the stirring blade We, where the shear force is highest, i.e., within a very short distance, for example, 2 mm, from the outer surface 20o of the cylindrical portion 20 and the inner and outer circumference of the perforated plate 18P. This allows the shear force to affect more locations, thus enabling the production of uniform and fine particles.

[0071] Furthermore, a seventh modification of the crystallization apparatus 4 of the first embodiment can be considered as a crystallization method in which the stirring blade Wf ​​comprises a cylindrical portion 20, a rotating shaft 3 extending upward along the central axis O1 from the center of the cylindrical portion 20 in a plan view, and a cylindrical porous plate 18P provided concentrically with the cylindrical portion 20 on the radially outer side of the cylindrical portion 20, wherein the porous plate 18P is fixed to a connecting rod 11 extending radially outward from the outer circumferential surface 20o of the cylindrical portion 20, the second reaction liquid L2 can flow through the interior of the rotating shaft 3 and the cylindrical portion 20, and in the second liquid supply step, the second reaction liquid L2 is supplied radially outward from a plurality of second liquid supply sections 50b provided at vertical intervals on the outer circumferential surface 20o of the cylindrical portion 20. With such a crystallization method, the first reaction liquid and the second reaction liquid can be mixed more uniformly. Furthermore, the second reaction solution can be supplied to the inner and outer circumference of the stirring blade Wf, where the shear force is highest, i.e., within a very short distance, for example, 2 mm, from the outer surface 20o of the cylindrical part 20 and the inner and outer circumference of the perforated plate 18P, and the effect of the shear force can be applied to more locations, thus enabling the production of uniform and fine particles.

[0072] While embodiments and modified versions of this invention have been described in detail above with reference to the drawings, the specific configuration is not limited to these embodiments and modified versions. It also includes designs and other elements that do not depart from the spirit of this invention, as well as combinations of embodiments and modified versions.

[0073] For example, in the above embodiment, the product was obtained by mixing two types of reaction solutions, the first reaction solution L1 and the second reaction solution L2, but three or more types of reaction solutions may be mixed. [Industrial applicability]

[0074] According to embodiments of the present invention, it is possible to obtain a crystallization apparatus, crystallization system, and crystallization method in which the clearance between the stirring blade and the reaction liquid supply nozzle can be minimized without requiring high manufacturing precision, and the reaction start point can be set to a range within a very short distance, for example, 2 mm, from the inner and outer circumference of the stirring blade where the shear force is highest. [Explanation of symbols]

[0075] 1 Reaction vessel 2. Cylindrical section 3 rotation axes 4. Crystallization apparatus 5a First liquid supply section 5b Second liquid supply section 6 Outlet 7. Baffle (obstruction plate) 8 Disc section 9, h hole

Claims

1. A stirring blade having multiple holes that penetrate radially and that can rotate around a central axis, A bottomed cylindrical reaction vessel capable of concentrically housing the aforementioned stirring blades inside, A first liquid supply unit is provided in the reaction vessel and is capable of supplying the first reaction solution into the inside of the reaction vessel, A second liquid supply unit is provided on the stirring blade and capable of supplying a second reaction liquid to the inside of the reaction vessel, A crystallization apparatus characterized by comprising the following features.

2. The stirring blade comprises a cylindrical portion, a disc-shaped portion whose outer edge is fixed to the inner surface of the cylindrical portion, and a rotating shaft extending upward along the central axis from the center of the disc portion in a plan view. The crystallization apparatus according to claim 1, characterized in that the second reaction liquid can flow through the interior of the disc portion and the rotating shaft, and the second liquid supply portion is provided at the outer edge of the disc portion.

3. The crystallization apparatus according to claim 2, characterized in that the second liquid supply section is open downward.

4. The crystallization apparatus according to claim 2, characterized in that the second liquid supply section opens radially outward and penetrates the cylindrical section.

5. The crystallization apparatus according to claim 3 or 4, characterized in that, in the cylindrical portion above the disc portion, a plurality of holes penetrating in the radial direction are closed, and a disc-shaped second disc portion is provided at the upper end of the cylindrical portion, the outer edge of which is fixed to the inner circumferential surface of the cylindrical portion.

6. The crystallization apparatus according to claim 3, characterized in that the disc portion is provided at the upper end of the cylindrical portion.

7. The crystallization apparatus according to any one of claims 1 to 5, characterized in that the peripheral speed of the stirring blade is 5 m / sec or more and 50 m / sec or less.

8. The crystallization apparatus according to any one of claims 2 to 6, characterized in that when the clearance between the outer surface of the cylindrical portion and the inner surface of the reaction vessel is L3 and the height of the cylindrical portion is H, H / L3 is 10 or more.

9. The crystallization apparatus according to any one of claims 1 to 7, characterized in that a plurality of the second liquid supply units are provided.

10. The crystallization apparatus according to claim 1, wherein the stirring blade comprises a cylindrical portion, a disc base provided concentrically with the cylindrical portion at the upper end of the cylindrical portion, a rotating shaft extending upward along the central axis from the center of the disc base in a plan view, and a cylindrical porous plate provided concentrically with the cylindrical portion on the radially outer side of the cylindrical portion, the porous plate extending downward from the outer edge of the disc base, the second reaction liquid being able to flow through the interior of the rotating shaft, the disc base and the cylindrical portion, and a plurality of the second liquid supply sections provided on the outer circumferential surface of the cylindrical portion at vertical intervals.

11. The crystallization apparatus according to claim 1, wherein the stirring blade comprises a cylindrical portion, a rotating shaft extending upward along the central axis from the center of the cylindrical portion in a plan view, and a cylindrical porous plate provided concentrically with the cylindrical portion on the radially outer side of the cylindrical portion, the porous plate being fixed to a connecting rod extending radially outward from the outer circumferential surface of the cylindrical portion, the second reaction liquid being able to flow through the interior of the rotating shaft and the cylindrical portion, and a plurality of the second liquid supply portions being provided on the outer circumferential surface of the cylindrical portion at vertical intervals.

12. The crystallization apparatus according to claim 10 or 11, characterized in that extension tubes are provided extending radially outward from the plurality of second liquid supply sections.

13. A crystallization apparatus according to any one of claims 1 to 12, A retention tank for retaining the product transferred from the reaction tank, A circulation pump for circulating the product between the retention tank and the crystallization apparatus, A crystallization system characterized by comprising the following features.

14. A stirring blade having multiple holes that penetrate radially and rotating around a central axis, A bottomed cylindrical reaction vessel that concentrically houses the aforementioned stirring blades inside, A first liquid supply unit is provided in the reaction vessel and supplies a first reaction liquid into the inside of the reaction vessel, A crystallization apparatus comprising a second liquid supply unit provided on the stirring blade and capable of supplying a second reaction solution into the reaction tank, A first liquid supply step of supplying the first reaction solution from the first liquid supply unit to the reaction tank, A second liquid supply step in which the second reaction solution is supplied from the second liquid supply unit, A crystallization method characterized by comprising the following:

15. The stirring blade further comprises a cylindrical portion, a disc-shaped portion whose outer edge is fixed to the inner surface of the cylindrical portion, and a rotating shaft extending upward along the central axis from the center of the disc portion in a plan view, wherein the second reaction liquid can flow through the interior of the disc portion and the rotating shaft. The crystallization method according to claim 14, characterized in that in the second liquid supply step, the second reaction liquid is supplied downward from the outer edge of the disc portion.

16. The stirring blade further comprises a cylindrical portion, a disc-shaped portion whose outer edge is fixed to the inner surface of the cylindrical portion, and a rotating shaft extending upward along the central axis from the center of the disc portion in a plan view, wherein the second reaction liquid can flow through the interior of the disc portion and the rotating shaft. The crystallization method according to claim 14, characterized in that in the second liquid supply step, the second reaction liquid is supplied radially outward from the outer edge of the disc portion through the cylindrical portion.

17. The crystallization method according to claim 14, wherein the stirring blade comprises a cylindrical portion, a disc base provided concentrically with the cylindrical portion at the upper end of the cylindrical portion, a rotating shaft extending upward along the central axis from the center of the disc base in a plan view, and a cylindrical porous plate provided concentrically with the cylindrical portion on the radially outer side of the cylindrical portion, the porous plate extending downward from the outer edge of the disc base, the second reaction liquid being able to flow through the interior of the rotating shaft, the disc base and the cylindrical portion, and in the second liquid supply step, the second reaction liquid being supplied radially outward from a plurality of second liquid supply sections provided at vertical intervals on the outer circumferential surface of the cylindrical portion.

18. The crystallization method according to claim 14, wherein the stirring blade comprises a cylindrical portion, a rotating shaft extending upward along the central axis from the center of the cylindrical portion in a plan view, and a cylindrical porous plate provided concentrically with the cylindrical portion on the radially outer side of the cylindrical portion, the porous plate being fixed to a connecting rod extending radially outward from the outer circumferential surface of the cylindrical portion, the second reaction liquid being able to flow through the interior of the rotating shaft and the cylindrical portion, and in the second liquid supply step, the second reaction liquid being supplied radially outward from a plurality of second liquid supply sections provided at vertical intervals on the outer circumferential surface of the cylindrical portion.

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