JPH08323179A - Mixer of powder and granular material and mixing method using the mixer - Google Patents

Abstract

PURPOSE: To provide a powder and granular material mixer by which the miscibility and coating property are improved in the course of mixing and coating a powder and granular material and uniform mixing is promoted. CONSTITUTION: A powder and granular material is introduced into a rotating vessel 1 from an inlet 2, mixed and discharged from an outlet 4 provided with an outlet weir 3. In this mixer, the length of a mixing blade provided projectingly to the inner wall of the vessel 1 is controlled to <=1/2 of the total length of the vessel 1, the height to 0.5-1.5 times the amt. of the weir and the ratio of the height to length to 1.5/1 to 1/10. One or more mixing blades are arranged in a row in the axial direction of the vessel, and even-numbered rows are formed. The row closest to the inlet is inclined at an angle of 20-70 deg. to the vessel rotating direction, and the succeeding rows on the downstream side are inclined to the same angle alternately in the opposite directions. The blades in the adjacent rows are positioned so as not to be overlapped in the circumferential direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for mixing powder and granules, which is effective for remarkably improving the mixing property and coating property of detergent components in the detergent manufacturing process, and a mixing method using the same.

[0002]

2. Description of the Related Art In the detergent manufacturing process, it is a general-purpose technique to post-add some or all of the essential components and mix or coat them, but if this mixing or coating is insufficient. , The detergent composition cannot be made uniform, and stable product performance and quality cannot be obtained.
Therefore, post-additives, such as enzymes, bleaching agents, bleach activators, optical brighteners, softening agents, fragrances, etc., should be added in a small amount above the basic set amount to maintain performance and quality. It is common to strive for.

For the mixing and coating of such post-additives, a rotary cylinder type continuous mixer capable of processing them in large quantities is widely used. In recent years, however, detergents have become more compact and high bulk density detergents have been developed. (0.5 g / cc or more) is the mainstream, and the importance of manufacturing processes such as mixing, granulation, coating, etc. of powders and granules, which are detergent components, makes product performance uniform Stabilization of quality and improvement of productivity are desired.

The above-mentioned rotary cylinder type continuous mixer is characterized by the rotation of a cylindrical container whose rotation axis is horizontal or slightly inclined.
The granular material entered from the inlet on one end of the cylindrical container in the axial direction is mixed while being updated up and down, and discharged from the outlet on the other end of the container. When viewed in a cross section at right angles to the center of the powder and granules,
There is relatively little mixing between the bottoms. In order to improve this, conventionally, a fixed blade was provided on the inner surface of the container in parallel with the rotation axis to promote mixing between the center part and the upper and lower parts. Short-passed powder and granules are present, resulting in insufficient mixing. Further, when the difference in specific gravity between the particles of the mixture and that of the mixture is large, this tendency is particularly remarkable.

[0005]

SUMMARY OF THE INVENTION The technical problem of the present invention is to significantly improve the mixing property and coating property of powder particles during the mixing / coating process of powder particles, thereby reducing dust generation and at the same time improving fluidity. Another object of the present invention is to provide a mixing apparatus for powders and granules and a mixing method using the same. Another technical problem of the present invention is that the uniform mixing is promoted, whereby stable quality can be maintained, and as a result, the productivity is improved and the granular material is economically advantageous. Another object of the present invention is to provide a mixing device and a mixing method using the same.

[0006]

Means and Actions for Solving the Problems A powdery or granular material mixing apparatus according to the present invention for solving the above problems is provided by rotating a cylindrical container having its axis of rotation kept horizontal or inclined. A powdery or granular material mixing device comprising a rotary cylindrical continuous mixer in which the powdery or granular material entered from the inlet at the one axial end of the is mixed and discharged from the outlet at the other end of the container provided with an outlet weir, A mixing blade is projectingly provided on the inner wall of the cylindrical container, and the mixing blade has a length (L) of 1/2 or less with respect to the entire length of the cylindrical container and 0.5 to 1. 5
Have double height (H) and their ratio H / L is 1.
It is assumed that the mixing blades are in a range of 5/1 to 1/10, and the mixing blades are arranged in an even numbered row in the axial direction of the cylindrical container, with one or more blades for each row. The inlet side of the mixing blade is tilted with respect to the generatrix of the cylindrical container in the rotation direction of the container by 20 to 70 °, and in the subsequent mixing blade row on the downstream side, alternately tilted in the opposite direction by 20 to 70 °. The mixing blades in the adjacent mixing blade row are arranged at positions that do not overlap each other in the circumferential direction of the cylindrical container.

Further, in the method of mixing powder and granules according to the present invention, in which the powder and granules are mixed by using the above-mentioned mixing device, when the cylindrical container is rotated, the inlet side portion with respect to the generatrix of the cylindrical container is By the mixing blade inclined by 20 to 70 ° in the rotation direction of the above and the mixing blade inclined by 20 to 70 ° in the opposite direction on the downstream side, the powder particles are alternately folded in the axial direction of the cylindrical container. The stir flow is given to the powder and granules by this stirring, and the stir flow is given to the powder and granules. It is characterized in that it is performed at least 10 times or more on average before being discharged from the outlet.

According to the mixing apparatus of the present invention having such a structure and the mixing method using the same, the folding flow of the powder particles in the cylindrical container due to the special arrangement of the mixing blades causes As is clear from the examples described below,
Uniform mixing in the vertical and horizontal directions is possible, and the mixing property and coating property of the powder and granules can be remarkably improved, which reduces dust generation and at the same time improves the fluidity. Further, by promoting the above uniform mixing, it is possible to maintain stable quality of the product, and as a result, it is possible to improve productivity and become economically very advantageous. Therefore, it is possible to manufacture a detergent with high productivity. As a method of mixing equipment and detergent ingredients,
It can be effectively used.

The structure of the powder / granular material mixing apparatus of the present invention will be described more specifically. This mixing apparatus is basically a general-purpose rotary cylinder type continuous mixer as shown in FIG. Similarly, a cylindrical container 1 that rotates while holding the axis of rotation in a horizontal or inclined state is provided, and the rotation of the cylindrical container 1 mixes the granular material entered through the inlet 2 at one axial end of the container. , Outlet 4 at the other end of the container provided with outlet weir 3
The more it is discharged. The inclination of the cylindrical container with respect to the horizontal axis can be appropriately set in consideration of various conditions.

As shown in FIG. 2, the mixing blade 5 fixedly provided on the inner wall of the cylindrical container 1 has a length L of 1/2 or less of the total length of the cylindrical container and a height H. Has a substantially quadrangular shape that is 0.5 to 1.5 times the height of the outlet weir 3, and the height-to-length ratio H / L is 1.5 / 1 to 1
/ 10 is preferable, and more preferably 1/1 to 1/5. The bottom of the mixing blade 5 can be changed according to the shape of the cylindrical container 1, and the inner wall of the cylindrical container and the blade are provided to prevent powder particles from adhering to the mixing blade. A clearance C of about 50 mm or less may be provided.
If the height of the mixing blade 5 is lower than the above range, the folding flow described below will be insufficient, and if it is too high, it will not only contribute little to the mixing but will also be an obstacle during internal cleaning. Further, the thickness of the mixing blade may be such that strength can be maintained, but is usually 10 mm or less.

As shown in the development view of FIG. 3, the mixing blades 5 are formed by arranging an appropriate number of them in the circumferential direction on the inner surface of the cylindrical container 1 to form one mixing blade row, which is a cylinder. Are arranged in even rows in the axial direction of the cylindrical container 1 from the inlet 2 side toward the outlet 4 side. In the mixing blade row closest to the inlet side, the inlet 2 side portions of all the mixing blades 5 are arranged in the cylindrical container 1 Θ ₁ = 20 to 70 °, preferably 30 to 60 ° in the rotation direction of the container with respect to the generatrix line, and in the downstream blade row subsequent to the blade row, all the mixing blades 5 are set in the opposite direction. θ ₂ = 2
It is attached to the inner wall of the cylindrical container 1 with an inclination of 0 to 70 °, preferably 30 to 60 °, and in the following mixing blade row, the blades 5 are alternately and alternately inclined in opposite directions.

The number of blades per row of the mixing blade row is
The number of mixing blades 5 is preferably four to eight, and it is desirable that the plurality of mixing blades 5 are attached at equal intervals with respect to the circumferential length, as shown in FIG. The number of mixing blades 5 in adjacent blade rows is the same, and the mixing blades in both blade rows are arranged at positions that do not overlap each other in the circumferential direction of the cylindrical container, and preferably adjacent to each other. The mixing blades 5 in the blade row are arranged so as to face each other in the circumferential direction at intermediate positions. Furthermore, between adjacent mixing blade rows, the trailing edge of the blade row located on the upstream side and the leading edge of the blade row located on the downstream side are
In order to efficiently perform the folding flow, the cylindrical containers are mounted so as to be arranged on the same line in the circumferential direction. It is also possible to spray a liquid material such as a binder for dust prevention or a fragrance into the cylindrical container using a pressure nozzle.

As shown in FIG. 4, the mixing apparatus of the present invention has conical cones 11a, 11 at both ends of a cylindrical container 11.
It is also possible to attach b and further attach the mixing blade in the same manner. In this case, the folding flow is more effectively performed, and the mixing / coating effect is further promoted. However, in such a configuration, there is a problem that it is relatively difficult to discharge the powder or granules staying inside the cylindrical container 11 when the manufacturing type is changed. It is useful to have a normally closed outlet 16 as shown. When the conical cone is attached to the cylindrical container 11,
The inner surface of the conical cone can also be provided with one row of mixing vanes.

Next, the operation of the mixing apparatus having the above structure will be described in detail together with the mixing method of the present invention. In the above mixing device, the rotation of the cylindrical container 1 mixes the powdery or granular material entered through the inlet 2 at one axial end of the cylindrical container,
It is discharged from the outlet 4 at the other end of the container provided with the outlet weir 3, while the mixing blades 5 in the cylindrical container 1 meanwhile efficiently mix and coat the granular material by folding flow. Is done.

That is, in the cylindrical container 1, the blade row closest to the inlet is such that the mixing blades are inclined by θ ₁ = 20 to 70 ° in the rotational direction of the container with respect to the generatrix line, and the second downstream blade is provided. In the second row of mixing blades, θ ₂ = 20 to 70 ° in the opposite direction.
Although inclined, one adjacent mixing blade in each of these blade rows (two in total) constitutes a unit for performing a set of folding flow, and the granular material entering from the inlet 2 Is sent so as to be folded back toward the outlet 4 side by the mixing blade 5 in the first blade row as the cylindrical container 1 rotates, and then returned to the inlet 2 side by the mixing blade 5 in the next row. The movement to turn back is given.
Such a flow of the granular material is referred to herein as "folding flow". In the above-mentioned mixing device, when the inclination angles θ ₁ and θ ₂ of the mixing blade 5 deviate from the above range,
This folding flow becomes insufficient.

The mixing blades at the adjacent positions in the above-mentioned blade row on the most inlet side and the blade row next to it constitute the above-mentioned unit for performing the folding flow. Similarly, the third row and The fourth row of blades and the pair of mixing blades located in the vicinity of the pair of blades arranged on the downstream side thereof also constitute a unit for performing the above-mentioned folding flow.

In the method of mixing powder and granules of the present invention using the above mixing device, when the cylindrical container is rotated, the mixing blade inclined by θ _{1 with} respect to the generatrix of the cylindrical container and the reverse of the downstream side thereof. By the mixing blade inclined by θ _{2 in the} direction, the particles are given a fold-like flow that alternates forward and backward in the axial direction of the cylindrical containers 1 and 11 to agitate them, thereby giving them to the particles. Folding flow is performed on average at least 10 times or more during the period in which the powder and granular material enters from the inlet of the cylindrical container and is discharged from the outlet. 10 like this
As is clear from the examples shown below, the folding flow of more than one time effectively promotes uniform mixing, and a sufficient mixing / coating effect can be obtained, thereby maintaining stable product quality. it can.

The number of times of the folding flow is determined by the internal residence time of the powder and granules, the number of rotations of the cylindrical container, the number of blades, etc. When the number of times increases, the mixing / coating effect is promoted. However, if hollow particles such as conventional low bulk density detergents have difficulty in particle strength, there is a concern that the particles may be broken if the number of times is excessively increased. Therefore,
It is necessary to set various conditions appropriately based on the number of folding flows so that the mixing / coating effect reaches the allowable range. If the number of folding flow can be satisfied, the extra zone in the cylindrical container does not need to be provided with a mixing blade, and the extra zone is provided with a scraping blade parallel to the conventional horizontal axis. You can also do it.

The average number of folding flows can be obtained as follows. That is, assuming that the feed amount of the powdery particles is F kg / hr and the retention amount inside the cylindrical container after the test is H kg, the average retention time in the cylindrical container is given by T, T = H / F The flow number N is given by N = rotation number × average residence time × (number of blades / 2). The reason why the number of blades is multiplied by 1/2 is that the folding flow is performed once by a total of two mixing blades, one for each of the front and rear rows.

[0020]

EXAMPLES As a mixing apparatus, a cylindrical container having a diameter of 40 cm and a length of 60 cm was equipped with an outlet weir having a height of 5 cm, and the cylindrical container was arranged such that the rotation axis was horizontal so that the inlet side became higher. The results of a test conducted by inclining it by 2 ° and rotatably supporting it and adjusting the rotation speed of the cylindrical container as described below are shown. The manner of attaching the mixing blades to the inner wall of the cylindrical container is as shown in A to E below.

A, height 4 cm, length 10 cm, thickness 1 m
m mixing blades made of SUS flat plate, with a clearance of 1 cm from the inner wall of the cylindrical container, at equal intervals in the circumferential direction.
Six rows of the mixing blades were attached in the axial direction such that the front edge of the mixing blade was aligned with the rear edge of the front row blade. And
In each row, these mixing blades were mounted so that the circumferential position was in the middle of the blades in the front row. The horizontal axis mounting angle of each mixing blade is changed as shown below, and a flat plate having a height of 5 cm and a thickness of 1 mm is provided in the extra zone in the lengthwise direction of the cylindrical container with a rotation axis of the cylindrical container. Two pieces were attached in parallel with and at equal intervals in the circumferential direction.

B, height 5 cm, length 30 cm, thickness 1 m
The mixing blade made of a SUS flat plate of m was cut so as to be in close contact with the inner wall of the cylindrical container, and each row was divided into two rows, and θ ₁ and θ ₂ were 45 with respect to the generatrix of the cylindrical vessel, respectively. °
Then, the second row was attached so as to be on the opposite side in the circumferential direction with respect to the attachment position of the mixing blade in the first row. C, a height of 2 cm, a length of 30 cm, and a mixing blade made of a SUS flat plate having a thickness of 1 mm were attached in the same manner as in the above B. D, 5 cm in height, 60 cm in length, and 1 mm in thickness, and two mixing blades made of a SUS flat plate were attached in parallel to the rotation axis of the cylindrical container and at equal intervals in the circumferential direction (Comparative Example). E, no mixing blade is attached (comparative example).

Example 1 Table 1 shows the operation of adding 8% of sodium percarbonate (2Na ₂ CO ₃ .3H ₂ O ₂ ) particles manufactured by Mitsubishi Gas Chemical Co., Inc. to a high bulk density detergent and mixing them. Under such conditions of the mixing blades and the rotation speed, continuous operation was performed for about 1 hour at a capacity of 360 kg / hr. As a result, the mixed powder discharged from the cylindrical container was sampled (12 points), the sodium percarbonate was quantified by the iodometry method, the average value of all points and the variation б _n were calculated, and The degree of mixing was judged. The average value and the variation are shown in Table 1 together with the test conditions.

The composition and properties of the powder and granules used are as follows. Sodium percarbonate: BD: 0.8 g / cc, average particle size: 700μ High bulk density detergent particles: BD: 0.75 g / cc, average particle size: 530μ (α-olefin sulfonic acid Potassium: 12.5%, potassium linear alkylbenzene sulfonate: 15.0%,
Soap: 3.0%, polyoxyethylene alkyl ether (C ₁₂ ethylene oxide: 25 mol added): 5.0
%, Zeolite: 15.0%, potassium carbonate: 5.0
%, Sodium silicate: 4.0%, sodium carbonate: balance, water content: 7.0%)

[0025]

[Table 1]

[Example 2] With the capacity of 360 kg / hr, the detergent particles obtained in Example 1 contained 3% (pure content) of zeolite powder having a primary particle size of about 1μ (Shilton B, manufactured by Mizusawa Chemical Co., Ltd.).
Was added to a cylindrical container so that the coating operation of zeolite was continuously carried out. The coating particles discharged from the outlet of the cylindrical container were sampled at 3 points every 10 minutes, the coating rate and the fluidity (angle of repose) were measured, and the results are shown in Table 2 together with the test conditions. The angle of repose of the detergent particles alone is 70 °.

[0027]

[Table 2]

[0028] The above coating rate is the same as the detergent particles (A
Powder) and the product discharged from the cylindrical container (B powder) are finely cut using a sieve with an opening of 105 μm to determine the zeolite content, and the coating rate (%) = [(zeolite content of B powder-A powder Zeolite content) / 3] × 100.

[0029]

[Effects of the Invention] According to the mixing apparatus and mixing method of the present invention detailed above, the mixing property and coating property of the powder particles during the mixing / coating process of the powder particles are remarkably improved. As a result, less dust is generated and at the same time fluidity can be improved, and uniform mixing is promoted, so stable quality can be maintained, and as a result, productivity is improved and economic efficiency is improved. Even if it is advantageous, it can be done. In particular, when the above-mentioned apparatus and method are used for coating, it is possible to produce detergent particles having dust generation and improved fluidity, which can be effectively utilized for producing a detergent with high productivity.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a mixing device according to the present invention.

FIG. 2 is an explanatory diagram for explaining a configuration of a mixing blade in the mixing device.

FIG. 3 is a development view showing an arrangement state of the mixing blades in a cylindrical container.

FIG. 4 is a schematic configuration diagram of another configuration example of the mixing device according to the present invention.

[Explanation of symbols]

 1,11 Cylindrical container 2 Inlet 3 Outlet weir 4 Outlet 5 Mixing blade

Claims (2)

[Claims] 1. A cylindrical container having its axis of rotation kept horizontal or inclined to mix the powder or granules introduced through an inlet at one axial end of the cylindrical container, and the other end of the container provided with an outlet weir. A mixing device for powder and granules comprising a rotating cylindrical continuous mixer which is discharged from the outlet of the mixing container, wherein mixing blades are provided on the inner wall of the cylindrical container so as to project the entire length of the cylindrical container. Has a length (L) of 1/2 or less, and a height (H) 0.5 to 1.5 times the height of the outlet weir, and the ratio H / L thereof is 1.5. /
It should be in the range of 1 to 1/10, and the mixing blade is 1 in each row in the axial direction of the cylindrical container.
Arranged in even rows with more than one sheet, the mixing blade row on the most inlet side is
The inlet side of the mixing blade is inclined 20 to 70 ° with respect to the generatrix of the cylindrical container in the rotation direction of the container, and the subsequent mixing blade rows on the downstream side are alternately alternately arranged in the opposite direction from 20 to 70 °.
A mixing apparatus for powder particles, wherein the mixing blades are inclined at 70 °, and the mixing blades in adjacent mixing blade rows are arranged at positions not overlapping each other in the circumferential direction of the cylindrical container. 2. A method for mixing powdery or granular material using the mixing device according to claim 1, wherein the inlet side portion is formed with respect to the generatrix of the cylindrical container when the cylindrical container is rotated. By the mixing blade inclined by 20 to 70 ° in the rotation direction of the above and the mixing blade inclined by 20 to 70 ° in the opposite direction on the downstream side, the powder particles are alternately folded in the axial direction of the cylindrical container. The stirring flow is applied to the granular material, and the folding flow applied to the granular material is averaged at least 10 times or more until the granular material enters from the inlet of the cylindrical container and is discharged from the outlet. A method for mixing powder and granules, which comprises: