Classifying rotor and classifying device

Abstract

Classifying rotor comprising a rotatable frame body with an opening section on an outer circumferential section and with an ejection opening (22) for ejecting a fluid that has flowed in through the opening section to the outside; a plurality of classifying blades (23) arranged at a desired distance in a circumferential direction on an outer circumferential section in the frame body, and a plurality of rectifier blades (25), characterized in that the ejection opening (22) is arranged in a central region of the rotor body and that the rectifier blades (25) are arranged at a desired distance in the circumferential direction and radially inside the classifying blades (23) in the frame body.

Description

Technical field

[0001] The present invention relates to a classifying rotor configured, for example, for classifying fine particles in a gas or liquid. Furthermore, the present invention relates to a dry or wet classifying device comprising the classifying rotor. In particular, the present invention provides a classifying rotor and a classifying device with extremely high classification accuracy. According to the present invention, only minimal mixing with coarse particles occurs, and a sharp particle size distribution can be achieved. State of the art

[0002] Classifying devices include a dry classifier, which classifies fine particles in gases such as air, and a wet classifier, which classifies fine particles in a liquid such as a suspension. Both classifiers classify the fine particles by rotating classifying rotors at high speed, with classifying blades circumferentially separated and arranged radially to a center of rotation. Alternatively, both classifiers classify the fine particles by rotating the classifying rotors at high speed, with the classifying blades circumferentially separated and arranged slightly eccentrically to the center of rotation (with some inclination in a radial direction).

[0003] A classification mechanism is designed as follows. First, a fluid, such as a gas or liquid, flows from an outer circumferential section into a classification chamber formed between each of the adjacent classifying blades of the classifying rotor. As this fluid moves from the outer circumferential section to an inner circumferential side, the particles in the fluid are subjected to a centrifugal force F due to the high-speed rotation of the classifying rotor and to air resistance R, since the fluid flows in the inner circumferential direction opposite to the direction of this centrifugal force. Coarse particles, whose size is larger than the classifying particle size at which equilibrium exists (F = R), are ejected from the classifying rotor. Simultaneously, fine particles with a size smaller than the classifying particle size at which equilibrium exists flow into the classifying rotor.

[0004] Fig. Figure 16 shows a schematic configuration diagram of an entire classification system with a dry classification device. 1 The classifying device 1 For example, a housing includes 2 , one inside the case 2 intended classifying rotor 3 , a rotary device 4 to rotate the classifying rotor 3 and an outflow chamber 5 , which causes the classifier rotor 3 classified and into the classifying rotor 3 fine particles flowing out of the casing 2 outflow. The rotating device 4 includes, for example, a motor (not shown) and a rotating shaft. 4a , which is rotated / driven by the motor.

[0005] First, a raw material is taken, e.g. from a raw material feeding device. 6 together with air from a supply opening 2a the case 2 the classifying device 1supplied. The raw material is then passed through the housing. 2 intended and high-speed rotating classifying rotor 3 The particles are classified into coarse and fine particles. The coarse particles are ejected from an outlet. 2b of the case 2 in the classifying device 1 ejected and into a container 7 Furthermore, the fine particles that escape from the outer circumferential section of the classifying rotor are captured. 3 into the classifying rotor 3 have flowed through an ejection opening 8 , which are located around a central part of the classifying rotor 3 trained rotating shaft 4a of the classifying rotor 3 is formed around, to the outflow chamber 5 ejected, which is connected to the ejection port 8 is connected. Then the parts from the housing are removed. 2 via the outflow chamber 5The escaping fine particles are recovered, for example, by a (not shown) fine particle recovery tank via an (not shown) insect filter that separates the fine particles from the air.

[0006] Furthermore, it shows Fig. 17 a schematic configuration of the entire classification system with a dry classification device 9 The classifying device 9 For example, a housing includes 10 , one inside the case 10 intended classifying rotor 11 , a rotary device 12 to rotate the classifying rotor 11 and a through hole 13 , which runs in an axial direction and in a rotating shaft 12a the rotary device 12 is trained to cause the classifying rotor 11 classified and into the classifying rotor 11 fine particles flowing out of the casing 10 outflow. The rotating device12 includes, for example, a motor (not shown) and the rotating shaft. 12a , which is rotated / driven by the motor.

[0007] Here, for example, a raw material suspension is drawn from a raw material suspension tank. 14 with a dosing pump 15 through a feed opening 10a into the case 10 the classifying device 9 The raw material suspension is then conveyed through the classifying device. 9 intended and high-speed rotating classifying rotor 11 The particles are classified into coarse and fine particles. The coarse particles are ejected through a discharge opening. 10b of the case 10 in the classifying device 9 from the case 10 ejected. In addition, the fine particles that flow from an outer circumferential section of the classifier rotor are expelled. 11 into the classifying rotor 11 have flowed through the through-hole 13 the rotating shaft12a , which have an ejection opening 16 is connected and attached to the classifying rotor 11 is attached, from the ejection opening 16 , which are located on a central part of the classifying rotor 11 is trained, and are placed in a recovery tank 17 Recovered.

[0008] The two classifying rotors 3 and 11They feature a rotatable frame body with an opening section on the outer circumferential section to direct the fluid, such as a gas, liquid, and the like, into the housing, and with the discharge opening on the central section to expel the fine particles that have flowed into the classifying rotor from the classifying rotor, as well as classifying blades arranged radially to a center of rotation on the outer circumferential section in the frame body at a desired distance in a circumferential direction or slightly eccentrically to the center of rotation (arranged with a certain inclination to a radial direction).

[0009] The classifying rotors 3 and 11 consist of, as in Fig. 18 and Fig. 19 shown, for example, from the frame body, which consists of two disc-shaped plates 18a and 18b of the same shape, which are arranged coaxially and separated vertically from each other, and from the ejection opening 8(16), located in the middle part of the upper plate 18a is provided for, as well as from a variety of classifying blades 19 , which are radially to the center of rotation at an equal distance in the circumferential direction between outer circumferential sections of mutually facing surfaces of the two plates 18a and 18b are provided, or are provided slightly eccentric to the center of rotation (with a certain inclination towards the radial direction). In addition, there is a space between the adjacent classifying blades. 19 a classification chamber 20 educated.

[0010] Regarding the dry classification device, for example, the patent specification 1 to be cited. Regarding the wet classification device, for example, the patent specification is relevant. 2 to quote.

[0011] In conventional classifiers, the particle size at which centrifugal force and air resistance are in equilibrium increases towards the inner circumference of the classifying chamber. Because the liquid on the outside of the high-speed rotating classifying rotor is in a turbulent state, coarse particles larger than the intended particle size do jump into the classifying chamber. However, if there is only a small difference between the particle size and the grain size, they mix on the inner circumference and reach the center, and there is a risk that they will be recovered as is.

[0012] Therefore, an improved classifying rotor is provided which is designed such that a classified particle size, where centrifugal force F = air resistance R applies, becomes a constant size (same size) over the entire area in the radial direction from the outer circumference (a circumference between distal ends of the adjacent classifying blades) to the inner circumference (a circumference between base sections of the adjacent classifying blades) of the classifying chamber (Patent 3). List of literature on patent literature Patent specification 1: Japanese published patent application no. 2011-72993 Patent specification 2: Japanese published patent application no. 2002-143707 Patent specification 3: WO2018 / 030429 Summary of the invention Technical task

[0013] Examples of the improved classifying rotors 3 and 11 are, for example, in Fig. 20 and Fig. 21. Examples of improved classifying rotors are shown. 3 and 11 is the classifying bucket 19 shaped such that a thickness t in the circumferential direction from the distal end (outer circumferential end) to the base section (inner circumferential end) is constant (equal) and a height of the classifying rotor in a rotational wave direction increases from the distal end (outer circumferential end) to the base section (inner circumferential end).

[0014] A height T (d) of the classifying bucket 19 at a position of the diameter d of the classifying chamber 20 For example, it is determined using the following formula 1: T ( d ) = Q π d − tN ⋅ 1 D 1 2 ⋅ 2 × 894 d ⋅ n 2 ⋅ 18 η 9.8 ( ρ 2 − ρ 1 )

[0015] Here, the symbol Q represents the flow velocity of a fluid in the inner circumferential direction, N represents the number of classification chambers in the circumferential direction, D1 represents a classified particle size, n represents a rotational speed of the rotor, η represents a viscosity of the fluid, ρ1 represents a specific weight of the fluid, ρ2 represents a specific particle weight, and t represents a blade thickness (constant).

[0016] Furthermore, there are other examples of the improved classifying rotors. 3 and 11 e.g. in Fig. 22 and Fig. 23 shown. The other examples of the improved classifying rotors 3 and 11 are shaped in such a way that the height T of the classifying rotors of the classifying blades 19 in the direction of the rotational shaft from the distal end to the base section is constant (equal) and the thickness t in the circumferential direction from the base section (inner circumferential end) to the distal end (outer circumferential end) increases.

[0017] Furthermore, the thickness t (d) of the classifying blade is determined circumferentially at the position of the diameter d of the classifying chamber. 20 e.g., determined by the following formula 2. The circumferential thickness (hereinafter simply referred to as blade thickness) and a chord thereof are close to each other, and both are essentially treated as the same. t ( d ) = 1 N ⋅ [ π d − Q T × 1 D 1 2 × 2 × 894 d ⋅ n 2 × 18 η 9.8 ( ρ 2 − ρ 1 ) ]

[0018] Here, the symbol Q represents the flow velocity of a fluid in the inner circumferential direction, N represents the number of classification chambers in the circumferential direction, D1 represents a classified particle size, n represents a rotational speed of the rotor, η represents a viscosity of the fluid, ρ1 represents a specific weight of the fluid, ρ2 represents a specific particle weight, and T represents a blade height (constant).

[0019] It should be noted that, as in Fig. Figure 23 shows that the blade thickness t(d) at the inner circumferential end (base section) of the classifying blade can be set to 0.

[0020] In further examples of classifying rotors 3 and 11 is the classifying bucket 19 e.g. shaped so that the height of the classifying rotor increases towards the inner circumference in the direction of the rotating shaft and the thickness increases towards the outer circumference in the circumferential direction.

[0021] In addition, the height T(d) of the classifying bucket is 19 at the position of the diameter d of this classification chamber 20 and the thickness t(d) of the classifying blade 19 e.g. determined by the following formulas 3, 4 and 5. T ( d ) = Q E ( d ) ⋅ N ⋅ 1 D 1 2 ⋅ 2 × 894 d ⋅ n 2 ⋅ 18 η 9.8 ( ρ 2 − ρ 1 ) E ( d ) = π N ⋅ { b ⋅ d 2 − b ⋅ d 2 − a ⋅ d 1 d 2 − d 1 × ( d 2 − d ) } t ( d ) = π d N − π N ⋅ { b ⋅ d 2 − b ⋅ d 2 − a ⋅ d 1 d 2 − d 1 × ( d 2 − d ) }

[0022] Here, the symbol E(d) represents a distance between the blades at the position of the diameter d of the classifying chamber, a represents a distance coefficient between inner circumferential blades (πd1 - Nt1) / (πd1), b represents a distance coefficient between outer circumferential blades (πd2 - Nt2) / (πd2), d1 represents an inner circumferential diameter of the classifying chamber, d2 represents an outer circumferential diameter of the classifying chamber, t1 represents an inner circumferential thickness of the blade, t2 represents an outer circumferential thickness of the blade, Q represents a flow velocity of the fluid in the inner circumferential direction, N represents the number of classifying chambers in the circumferential direction, D1 represents a classified particle size, η represents a viscosity of the fluid, ρ1 represents a specific gravity of the fluid, and ρ2 represents a specific particle weight.

[0023] The improved classifying rotor prevents the entry of coarse particles and improves classification accuracy.

[0024] Furthermore, even if the classifying blade of the improved classifying rotor is slightly inclined with respect to the radial direction of the rotor, the entry of coarse particles can be prevented in a similar way and the classifying accuracy can be somewhat improved (see patent specification 3, Fig. 12).

[0025] The present invention further improves both the conventional and the improved classifying rotor. Furthermore, the present invention prevents the formation of a separation vortex on the rear surface of the classifying blade and improves classification accuracy.

[0026] Furthermore, the present invention provides a classifying rotor that prevents the waste of energy not contributing to the classification process through the generation of this separation vortex. The present invention also provides a classifying rotor that prevents wear on the classifying rotor. Solution

[0027] To achieve the aforementioned objective, the classifying rotor according to the present invention is formed by a rotatable frame body with an opening section on an outer circumferential section and with an ejection opening for ejecting a fluid that has flowed in through the opening section, and with a plurality of classifying rotors arranged at a desired distance in the circumferential direction on an outer circumferential section in the frame body, and the classifying blades are provided on the frame body such that an angle formed by a direction of the classifying blade and a direction of rotation of the frame body results in a desired angle of inclination, wherein the desired angle of inclination is an angle at which the classifying accuracy improves when the classifying blades are inclined such that the formed angle of 90 degrees gradually decreases.

[0028] Furthermore, the classifying blades are positioned on the frame body with regard to the desired angle of inclination, such that the angle formed is greater than 0 degrees and not greater than (or less than) 45 degrees, greater than 0 degrees and not greater than (or less than) 40 degrees, greater than 0 degrees and not greater than (or less than) 30 degrees, or greater than 0 degrees and not greater than (or less than) 20 degrees.

[0029] Furthermore, a multitude of rectifier blades are provided, arranged inside the frame body on the inside of the classifying blades at a desired circumferential distance. Additionally, a multitude of rectifier blades, arranged radially to a center of rotation or eccentrically to the center of rotation at a desired circumferential distance, are provided inside the frame body on the inside of the classifying blades.

[0030] Furthermore, the classifying rotor of the present invention is formed by a rotatable frame body with an opening section on an outer circumferential section and with an ejection opening for ejecting the fluid that has flowed in through the opening section, a plurality of classifying blades arranged at a desired distance in the circumferential direction on the outer circumferential section in the frame body, and a plurality of rectifier blades arranged at the desired distance in the circumferential direction inside the classifying blades in the frame body.Furthermore, the classifying rotor of the present invention is formed by a rotatable frame body with an opening section on an outer circumferential section and an ejection opening for ejecting the fluid flowing in through the opening section, a plurality of classifying blades arranged radially to the center of rotation or eccentrically to the center of rotation at a desired distance in the circumferential direction on the outer circumferential section in the frame body, and a plurality of straightening blades arranged radially to the center of rotation at a desired distance in the circumferential direction or eccentrically to the center of rotation on the inside of the classifying blades.

[0031] Furthermore, the classifying blade and / or the rectifier blade have an arc shape that follows the Bernoulli curve.

[0032] Furthermore, the shape of the classifying blade is designed so that the particle size to be classified is constant across the entire area in the radial direction from an outer circumference to an inner circumference in the classifying chamber formed between the adjacent classifying blades.

[0033] Furthermore, a classifying device of the present invention includes the classifying rotor. Advantageous effect of the invention

[0034] According to the present invention, only very minimal mixing with coarse particles occurs, and a sharp particle size distribution can be achieved. Furthermore, power consumption can be reduced. List of characters Fig. Figure 1 shows a perspective view of a classifying rotor according to one embodiment. 1 of the present invention. Fig. Figure 2 shows a side view of the classifying rotor according to the embodiment 1of the present invention. Fig. Figure 3 shows a cross-sectional view along a line AA in Fig. 2. Fig. Figure 4 shows a cross-sectional view of the classifying rotor according to a further embodiment of the design. 1 of the present invention. Fig. Figure 5 shows sectional views of the classifying rotors (shape 1 , form 2 , form 3 ) with angles formed by classifying blades that differ from each other. Fig. Figure 6 is a diagram showing the particle size distribution of each of the classifying rotors in Fig. 4 compares. Fig. Figure 7 shows a cross-sectional view of the classifier rotor (shape 4 ) the classifying blade based on the Bernoulli curve. Fig. Figure 8 is a diagram showing the particle size distribution of the classifying rotors of the form 3 and the form 4 compares. Fig. Figure 9 is a longitudinal section view to illustrate a formed angle. Fig. 10 is a table showing the shape coefficients Np of the individual classifying rotors of the shapes 1 , 2 , 3 and 4 shows. Fig. Figure 11 is a sectional view of a classifying rotor according to an embodiment. 2 of the present invention. Fig. Figure 12 shows a cross-sectional view of the classifying rotor according to a further embodiment of the design. 2 of the present invention. Fig. Figure 13 shows a diagram of the CFD analysis of a flow in the rotor of the classifying rotor (form 3 ) without rectifier blade and classifier rotor (shape 5 ) with rectifier blade (angle formed β = 90 degrees). Fig. 14 is a diagram showing schematic views of the flows in the classifying rotors of the form 3 and the form 5shows. Fig. 15 is a diagram showing the particle size distribution of the classifying rotors of the form 3 and the form 5 compares. Fig. Figure 16 is a schematic representation of the entire classification system with a conventional dry classification device. Fig. Figure 17 is a schematic representation of the entire classification system with a conventional wet classification device. Fig. Figure 18 is a longitudinal section side view of the conventional classifying rotor. Fig. Figure 19 is a cross-sectional view along a line BB in Fig. 18. Fig. Figure 20 is a longitudinal section side view of the improved conventional classifying rotor. Fig. 21 is a cross-sectional view along a line CC in Fig. 20. Fig. Figure 22 is a longitudinal section side view of another improved conventional classifying rotor. Fig. 23 is a cross-sectional view along a line DD in Fig. 22. Description of embodiments

[0035] Examples of embodiments of the present invention are described below. Design 1

[0036] Embodiment 1 of the present invention is described with reference to Fig. 1 to Fig. 10 described.

[0037] In the present invention, instead of the conventional classifying rotors, 3 and 11 a classifying rotor 21 used.

[0038] The classifying rotor 21 consists of a rotatable frame body with an opening section for guiding a fluid, e.g. a liquid such as a suspension and a gas, into the housings 2 and 10inwards on an outer circumferential section, as well as with an ejection opening for ejecting fine particles that have been directed into the rotor, from the rotor on a central section and a plurality of classifying blades arranged at a desired distance in a circumferential direction on an outer circumferential section of the frame body, wherein the classifying blades are provided with an inclination such that an angle α, which is defined by each of the classifying blades and a direction of rotation of the classifying rotor 21 formed, results in a desired angle of inclination.

[0039] The classifying rotor 21 consists of a frame body made up of two circular plates 21a and 21b is formed, which have the same shape and are vertically separated and arranged coaxially, and from an ejection opening 22 , located in the middle part of the upper disc plate 21a is provided for, as well as from a variety of classifying blades 23, which are equidistant between the outer circumferential sections of the facing surfaces of the two plates 21a and 21b are connected and intended.

[0040] The reference number 24 refers to a classifying chamber located between adjacent classifying blades. 23 and 23 is educated.

[0041] It should be noted that each of the classifying blades 23 e.g., they are all shaped the same way. Furthermore, each of the classifying blades consists of 23 from a flat plate whose shape, from a base section (inner circumferential end) to a distal end (outer circumferential end) of a blade surface, is, for example, straight on a front surface (surface facing the direction of rotation). Furthermore, each of the classifying blades is 23so that it is arranged at an equal distance in the circumferential direction, which is e.g. by an equal distance from the center of rotation of the classifying rotor. 21 is separate. Furthermore, each of the classifying blades is 23 e.g. provided in such a way that the formed angle α becomes the same angle.

[0042] Fig. Figure 3 shows an example of a classifying blade designed such that, for a given centrifugal force F = air resistance R, the classified particle size remains constant (uniform) in the radial direction across the entire area within the classifying chamber. This example illustrates a case where the classifying blade is shaped such that the height T of each blade is constant (uniform) in the direction of the classifying rotor's rotational shaft, and the thickness increases circumferentially from the base (inner circumferential end) to the distal end (outer circumferential end). It should be noted that classifying blades can be designed such that the classified particle size within the classifying chamber is not constant (uniform), or the thickness is constant (uniform), as in [example missing]. Fig. 4.

[0043] Furthermore, each of the classifying blades can 23The plate has an arc-shaped form from its base to its distal end, in contrast to a flat plate, whose shape is straight from its base (inner circumference) to its distal end (outer circumference) of the anterior surface. Furthermore, the arc can, for example, be based on a Bernoulli curve.

[0044] Furthermore, the angle α, which is determined by the classifying blade, refers to 23 and the direction of rotation of the classifying rotor 21 is formed at an angle defined by a direction (direction of the blade surface on the leading surface side) from the distal end to the base section of the blade surface. 23a on the front surface of the classifying bucket 23 and the direction of rotation at the distal end of the blade surface on the front surface side of the classifying blade 23 is formed. In other words, the angle α formed by the classifying blade. 23 and the direction of rotation of the classifying rotor21 formed refers to an angle formed by a line between the distal end (outer circumferential end) and the base section (inner circumferential end) of the blade surface. 23a on the front surface of the classifying bucket 23 drawn line and a line from a center of rotation of the classifying rotor 21 to the distal end (outer circumference end) on the front surface of the classifying blade 23 a line is formed that intersects at a right angle. In particular, it refers to, as in Fig. 3 shown, on the angle α formed by a direction Q from the distal end to the base section of the blade surface on the front surface side of the classifying blade and the direction of rotation P at the distal end of the blade surface on the front surface side of the classifying blade.

[0045] As various experiments and the like show, if the classifying blade is tilted so that the angle α formed gradually decreases from 90 degrees, the classification accuracy initially deteriorates (the mixing with coarse particles increases); however, with further tilting, an angle is found at which the classification accuracy improves and which is referred to as the desired tilt angle.

[0046] As various experiments and the like further show, if the classifying blade is tilted so that the angle α formed gradually decreases from 90 degrees, the classification accuracy initially deteriorates (the mixing with coarse particles increases); however, with further tilting, especially to 50 degrees or less or to 45 degrees or less, an angle is found at which the classification accuracy improves significantly more than the classification accuracy before, this angle being referred to as the desired tilt angle.

[0047] The angle at which classification accuracy improves refers to an angle at which, when the formed angle α is inclined so that it gradually decreases from 90 degrees, the classification accuracy, which was previously poor, begins to improve. Alternatively, the angle at which classification accuracy improves refers, for example, to an angle at which, with a further inclination of the angle relative to the angle at which classification accuracy begins to improve, the classification accuracy becomes better than the classification accuracy at the desired angle between the formed angle of 90 degrees and the angle at which classification accuracy begins to improve. Again, alternatively, the angle at which classification accuracy improves refers, for example, to...to an angle at which the classification accuracy, with further inclination of the angle compared to the angle at which the classification accuracy begins to improve, becomes better than the best classification accuracy at the angle between the formed angle of 90 degrees and the angle at which the classification accuracy begins to improve.

[0048] If there are several angles at which the classification accuracy begins to improve compared to the angle at which the classification accuracy deteriorates, each of these angles will be recognized as the angle at which the classification accuracy begins to improve.

[0049] Furthermore, the angle can be determined, for example, by taking into account a shape coefficient, which will be described later.

[0050] Furthermore, the desired angle of inclination is a value determined based on various experiments, and the resulting angle α is, for example, greater than 0 degrees and not greater than (or less than) 45 degrees, greater than 0 degrees and not greater than (or less than) 40 degrees, greater than 0 degrees and not greater than (or less than) 30 degrees, or greater than 0 degrees and not greater than (or less than) 20 degrees.

[0051] Next, the operation and effect of the classifying rotor will be explained. 21 described in the present invention.

[0052] The wet classification device is described below, and the same applies to the dry classification device.

[0053] In the wet classification device 9 For example, a raw material suspension is taken from the raw material suspension tank. 14 from the dosing pump 15 through the feed opening 10a into the case 10 the classifier device 9The raw material suspension is then conveyed through the classifying device. 9 intended and high-speed rotating classifying rotor 21 The particles are classified into coarse and fine particles. The coarse particles are then expelled through the discharge opening. 10b of the case 10 the classifying device 9 from the case 10 ejected. In addition, the fine particles that flow from the outer circumferential section of the classifier rotor are expelled. 21 into the classification chamber 24 of the classifying rotor 21 have flowed through a through-hole 31, which is connected to the discharge opening 22 is connected and in the rotating shaft 12a trained to work on the classifying rotor 21 is attached, from the ejection opening 22 , which are located on the middle part of the classifying rotor 21 is trained, and are in the recovery tank 17 Recovered.

[0054] A dissolved silica dispersion liquid (tap water) from Denka was used as the raw material suspension. The peripheral speed of the classifying rotor was set to 20 m / s.

[0055] A test was conducted to determine the classification accuracy, using the classification blade. 23 The chamber was tilted, and the resulting angle α was gradually reduced from 90 degrees. Consequently, as the tilt angle α decreased from 90 degrees to approximately 45 degrees, the shape coefficient and classification accuracy worsened. However, at an angle no greater than the desired tilt angle, i.e., at a steep tilt of, for example, 40 degrees or less, turbulence in the classifying chamber was reduced, and classification accuracy was improved by preventing the mixing of coarse particles. Furthermore, it was observed that power consumption was also reduced.

[0056] The classifying blade is then tilted to the desired angle such that the resulting angle α is, for example, greater than 0 degrees and not greater than (or less than) 45 degrees. Alternatively, the classifying blade is tilted to the desired angle such that the resulting angle α is greater than 0 degrees and not greater than (or less than) 40 degrees. Another alternative is tilting the blade to the desired angle such that the resulting angle α is greater than 0 degrees and not greater than (or less than) 30 degrees. Finally, the classifying blade is tilted to the desired angle such that the resulting angle α is greater than 0 degrees and not greater than (or less than) 20 degrees. By setting these desired tilt angles, the classification accuracy is improved and the shape coefficient is reduced, thereby reducing throughput.

[0057] Fig. 5(a), Fig. 5(b) and Fig. Figure 5(c) shows a sectional view of the classifying rotor (shape 1), wherein the angle α formed by the classifying blade is 75 degrees, a sectional view of the classifying rotor (shape 2), wherein the angle α formed by the classifying blade is 60 degrees, and a sectional view of the classifying rotor (shape 3), wherein the angle α formed by the classifying blade is 30 degrees. Furthermore, Fig. Figure 6 shows a diagram comparing the particle size distribution of fine particles for the case where the raw material suspension was classified by each of the classifying rotors of shapes 1, 2, and 3. Furthermore, in Fig. 6 the transverse axis represents the particle size (µm) and the vertical axis a volume-based frequency (%).

[0058] As in Fig. As shown in Figure 6, the mixing of coarse particles in the particle size distribution is increased in the case of the formed angle α of 60 degrees (Form 2), which is steeper than in the conventional rotor with the formed angle α of 75 degrees (Form 1). Therefore, it can be concluded that the classification accuracy deteriorates when the formed angle α is changed to 60 degrees.

[0059] However, the mixing of the coarse particles in the particle size distribution is reduced when the angle α is further inclined, to 30 degrees (Form 3), compared to the classification distribution at an angle α of 75 degrees (Form 1) or 60 degrees (Form 2). Therefore, it can be concluded that the classification accuracy is improved by a steep inclination of the classifying blades.

[0060] Furthermore, it shows Fig. 7 a sectional view of the classifying rotor (shape 4) in which the angle α formed by the classifying blades is 30 degrees and the shape from the base section to the distal end of the classifying blades forms a Bernoulli curve. Fig. Figure 8 is a diagram comparing the particle size distribution of the fine particles when the raw material suspension is classified by the classifying rotors with shapes 3 and 4, respectively. Furthermore, Figure 8 shows... Fig. 8 the transverse axis the particle size (µm) and the vertical axis the volume-based frequency (%).

[0061] As in Fig. As shown in Figure 8, the high classification accuracy can be maintained, similar to that of straight classifying blades, even if the shape from the base section to the distal end of the classifying blades is designed as a Bernoulli curve. Furthermore, as described below, if the shape from the base section to the distal end of the classifying blades forms a Bernoulli curve, the coefficient of performance (COP) Np can be reduced, thus minimizing unnecessary power consumption and wear of the classifying rotor.

[0062] If the shape from the base section to the distal end of the classifying blades is an arc shape, such as the Bernoulli curve with the expanding / protruding leading edge of the blade surface, the angle α formed refers to an angle formed by the direction from the distal end (outer circumferential end) to the base section (inner circumferential end) of the blade surface. 23a on the front surface of the classifying blades 23and by the direction of rotation at the distal end (outer circumferential end) of the blade surface on the front surface side of the classifying blades 23 is formed, as in Fig. Figure 9 shows. In other words, the angle α formed refers to an angle formed by a line between the distal end (outer circumferential end) and the base section (inner circumferential end) of the blade surface. 23a on the front surface of the classifying blades 23 drawn line and one line from the center of rotation of the classifying rotor 21 to the distal end (outer circumference end) on the front surface of the classifying blade 23 formed at a right angle to the intersecting line.

[0063] Fig. Item 10 is also a table that gives the shape coefficient Np of each of the classifying rotors with shapes 1, 2, 3 and 4.

[0064] Furthermore, the power input P required for the rotation of the classifying rotor can be expressed by formula 6: P = Np ⋅ ρ ⋅ N 3 ⋅ d 5

[0065] Here, the symbol P represents the power input, ρ the fluid density, N the rotational speed of the rotating body, d the diameter of the rotating body, and Np the shape coefficient of the rotating body and the housing.

[0066] Formula 6 allows the magnitude of the power consumption P of the classifying rotor to be expressed by the shape coefficient Np. Furthermore, it can be determined from Fig. It is evident from Figure 10 that the shape coefficient Np of the classifying rotor (shape 2) with the formed angle α of 60 degrees is greater than that of the classifying rotor (shape 1) with the formed angle α of 75 degrees. However, the shape coefficient Np of the classifying rotor (shape 3) with the formed angle α of 30 degrees is smaller than that of the classifying rotor (shape 2) with the formed angle α of 60 degrees. Therefore, it was found that the Np of the rotating rotor of the present invention decreases when the tilt angle is reduced compared to the desired tilt angle, thereby reducing the power consumption P.

[0067] Furthermore, the coefficient of performance (COP) Np can be reduced more significantly than with a straight classifying blade by shaping the blade from its base to its distal end as a Bernoulli curve. Therefore, unnecessary power consumption and wear on the classifying rotor can be reduced by shaping the blade from its base to its distal end as a Bernoulli curve.

[0068] According to the present invention, only very few coarse particles are mixed, and a sharp particle size distribution can be achieved by adjusting the above-mentioned angle to the angle α formed by the classifying blade. Design 2

[0069] At the in Fig. 11 embodiment 2 of the present invention, in the classifying rotor 21 embodiment 1, in the conventional classifying rotors 3 and 11or the improved classifying rotors and the like, is a plurality of rectifier blades arranged radially to the center of rotation in the circumferential direction or eccentrically to the center of rotation (arranged with an inclination to the radial direction) at a desired distance in the circumferential direction. 25 inside of the classifying blades 23 and 19 provided in the frame body.

[0070] Each of the rectifier blades 25 is formed with the same shape. Furthermore, each of the rectifier blades is 25 formed by a flat plate, which, for example, has a straight shape from the base section (inner circumferential end) to the distal end (outer circumferential end) of the blade surface on the front surface. Furthermore, each of the rectifier blades 25 designed, for example, to be equidistant from the centers of rotation of the classifying rotors. 21 , 3 and 11is separated and arranged at equal intervals in the circumferential direction. Furthermore, each of the rectifier blades is 25 designed so that, for example, the angle of inclination to the radial direction is the same.

[0071] The number of classifying blades and rectifier blades 25 is not subject to any particular limitation. Preferably, the number of rectifier blades 25 smaller than the number of classifying blades. However, if it is too small, the rectifying effect is lost, which is why the number of rectifying blades must be increased. 25 e.g. an integer 1 / 4 time or more to the number of classifying paddles, an integer 1 / 3 time or more to the number of classifying paddles, or an integer 1 / 2 time or more to the number of classifying paddles.

[0072] Furthermore, the classifying blades and the rectifier blades 25 separated by the desired distance.

[0073] In the Fig. In embodiment 2 shown in 11, the rectifier blade is 25 for example, designed so that an angle β formed by the rectifier blade 25 and the direction of rotation of the classifying rotor is 90 degrees. The angle β formed can be provided with such an inclination that it is greater than the aforementioned 45 degrees and not greater than 135 degrees, as in Fig. 12 shown.

[0074] The rectifier blade 25 and the angle β formed by the direction of rotation of the classifying rotor refers to an angle formed by the direction (direction of the blade surface on the front surface side) from the distal end (outer circumferential end) to the base section (inner circumferential end) of the blade surface on the front surface side of the rectifier blade. 25and the direction of rotation at the distal end (outer circumferential end) of the blade surface on the front surface side of the rectifier blade 25 is formed. In other words, the angle β formed by the rectifier blade. 25 and the direction of rotation of the classifying rotor refers to an angle formed by a line between the distal end (outer circumferential end) and the base section (inner circumferential end) of the blade surface on the leading surface side of the rectifier blade. 25 drawn line and through a line from a center of rotation of the classifying rotor 21 to the distal end (outer circumference end) on the front surface side of the rectifier blade 25 a line is formed that intersects at a right angle. In particular, it refers to, as in Fig. 12 shown, on the angle β, which is formed by a direction S from the distal end to the base section of the blade surface on the front surface side of the rectifier blade and a direction of rotation R at the distal end of the blade surface on the front surface side of the rectifier blade.

[0075] The example of the classifying scoop in Fig. Figure 12 presents an example of a classifying blade designed such that the classified particle size, at which centrifugal force F = air resistance R, remains constant across the entire radial area of ​​the classifying chamber. This example of a classifying blade is shaped such that the height T of each classifying blade is constant in the direction of the rotating shaft of the classifying rotor, and the thickness increases circumferentially from the base (inner circumferential end) to the distal end (outer circumferential end).

[0076] Furthermore, each rectifier blade can 25 The plate has an arc shape from its base to its distal end, unlike a flat, straight plate. Furthermore, the arc can be shaped like a Bernoulli curve.

[0077] The following describes the action and effect of the classifying rotor with the rectifier blade. 25 described in the present invention.

[0078] According to this embodiment, the rectifier blade can be provided 25 The goal is to ensure that the fluid flow on the inside of the classifying blade in the rotor becomes constant in the circumferential direction.

[0079] Fig. Figure 13 shows a diagram of the CFD (Computational Fluid Dynamics) analysis of the flow in the rotor of the classifying rotor (shape 3) without a rectifier blade and the classifying rotor (shape 5) with a classifying blade (formed angle β = 90 degrees), when the angle α formed by the classifying blade is 30 degrees. In shape 3 without a rectifier blade, the flow direction of the fluid on the inside of the classifying blade in the rotor is not constant at one point in the circumferential direction. In shape 5 with a rectifier blade, however, the flow direction of the fluid is constant at one point in the circumferential direction, and it can be seen that the disturbance has been corrected.

[0080] Furthermore, Fig. Figure 14 shows a diagram illustrating schematic views of the currents in the classifying rotors in the cases of Form 3 and Form 5. Form 3 lacks a rectifier blade. 25A disturbance in the classification effect generated between adjacent classifying blades can be observed in the classifying chamber. However, in design 5 with the rectifier blade, the disturbance in the fluid flow from the classifying chamber in the inner circumferential direction is prevented and rectified. Thus, the disturbance in the classifying chamber is apparently eliminated. 24 prevented.

[0081] Fig. Figure 15 is a diagram comparing the particle size distribution of the fine particles when the raw material suspension is classified by classifying rotors of shape 3 without a rectifier blade and of shape 5 with a rectifier blade, where the angle α formed is 30 degrees. Fig. Figure 15 shows the particle size (µm) along the transverse axis and a volume-based frequency (%) along the vertical axis. Fig. As can be seen in Figure 15, the classification accuracy of the Form 5 is significantly improved with the rectifier blade.

[0082] In a conventional classifying rotor without a rectifier blade, the fluid flow entering from the outer circumferential section and passing over the classifying blade becomes unstable, affecting the flow conditions in the classifying chamber and reducing classification accuracy. However, the fluid flow on the inside of the classifying blade can be stabilized by providing the rectifier blade. This stabilizes the flow conditions in the classifying chamber and significantly improves classification accuracy. Commercial applicability

[0083] The classifying device according to the present invention can be used in industrial applications for the general wet and dry classification of any powder particles down to micron or even submicron size. This can be used, for example, in the metal industry, the chemical industry, the pharmaceutical industry, the cosmetics industry, the pigment industry, the ceramics industry, and other sectors. Reference symbol list 1 Classifying device 2 cases 2a Feed opening 2b Ejection opening 3 Classifying rotor 4 Rotary device 4a Rotary shaft 5 Outflow chamber 6 Raw material feeding device 7 containers 8 Ejection port 9 Classifying device 10 cases 10a Feed opening 10b Ejection port 11 Classifying rotor 12 Rotary device 12a Rotary shaft 13 Through hole 14 Suspension tank 15 pump 16 Ejection port 17 Recovery tank 18a plate 18b plate 19 Classifying shovel 20 Classification Chamber 21 Classifying rotor 21a Platte 21b plate 22 Ejection port 23 Classifying bucket 23a Shovel area 24 Classification Chamber 25 rectifier blade QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 201172993

[0012] JP 2002143707

[0012] WO 2018 / 030429

[0012]

Claims

[1] Classifying rotor, comprising: a rotatable frame body with an opening section on an outer circumferential section and with an ejection opening for ejecting a fluid that has flowed in through the opening section to the outside, and a plurality of classifying blades arranged at a desired distance in a circumferential direction on an outer circumferential section in the frame body, wherein the classifying blades are designed such that an angle formed by a direction of the classifying blades and a direction of rotation of the frame body results in a desired angle of inclination, and The desired angle of inclination is an angle at which the classification accuracy improves when the classifying blades are inclined so that the angle formed gradually becomes less than 90 degrees. [2] Classifying rotor according to claim 1, wherein the desired tilt angle is the angle formed which is greater than 0 degrees and not greater than 45 degrees. [3] Classifying rotor according to claim 1 or 2, wherein the classifying blade has an arc shape corresponding to a Bernoulli curve. [4] Classifying rotor according to claim 1, 2 or 3, further comprising a plurality of rectifier blades arranged at a desired distance in the circumferential direction inside the classifying blade in the frame body. [5] Classifying rotor according to claim 1, 2, 3 or 4, wherein a form of the classifying blade is designed such that the classified particle size is constant over an entire area in the radial direction from an outer circumference to an inner circumference in a classifying chamber formed between the adjacent classifying blades. [6] Classifying rotor comprising a rotatable frame body with an opening section on an outer circumferential section and with an ejection opening for ejecting a fluid that has flowed in through the opening section to the outside; a multitude of classifying blades arranged at a desired distance in a circumferential direction on an outer circumferential section in the frame body, and a multitude of rectifier blades arranged at a desired distance in the circumferential direction inside the classifying blades in the frame body. [7] Classifying rotor according to claim 6, wherein a form of the classifying blades is designed such that the classified particle size is constant over an entire area in the radial direction from an outer circumference to an inner circumference in a classifying chamber formed between the adjacent classifying blades. [8] Classifying device with the classifying rotor according to any one of claims 1 to 7.