JP4323602B2 - Rotary kiln - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a rotary kiln for heating powder. The heating referred to here includes heating performed for drying, pyrolysis or reaction.
[0002]
[Prior art]
A rotary kiln that heats powder is known, for example, provided with fixed blades (stirring means) that do not rotate in order to uniformly stir the powder charged into the kiln body. However, the powder that moves from one end to the other while being heated in the kiln body is fixed depending on factors such as the type, properties, and particle size of the kiln body, Adhere to the blade itself. In particular, when the powder is resin, magnesium oxide, calcium oxide or the like, this phenomenon is remarkable. Once attached to the inner wall or fixed blade of the kiln body, the deposits grow greatly, and in an extreme case, the inside of the kiln body may be blocked.
[0003]
As a rotary kiln that does not allow powder to be heated to adhere, for example, a heat-resistant rod longer than its inner diameter is present in the kiln main body, and inorganic powder is fired (Japanese Patent Laid-Open No. 2-166385). This rotary kiln prevents adhesion of sticky substances to the inner wall of the kiln when inorganic powder is baked by a heat resistant rod, and enables long-time operation.
[0004]
On the other hand, as a means for removing deposits adhering to the inner wall of a rotary kiln, there is known a method in which a large and small metal lump is put into a kiln body and heated while rotating to remove deposits (Japanese Patent Laid-Open No. 7-103672). Publication).
[0005]
[Problems to be solved by the invention]
In the case where a heat-resistant rod is present inside the kiln body (Japanese Patent Laid-Open No. 2-166385), deposits adhere to the inner wall of the kiln body and the heat-resistant rod due to melting of the raw material inorganic material. In particular, when the raw material inorganic material is sticky, this tendency is remarkable. However, since the heat-resistant rod presses the lower wall surface in the kiln main body only by gravity, the deposits attached to the inner wall of the kiln main body and the heat-resistant rod adhere and grow without stirring. Further, the raw material inorganic material tends to stay in the lower part in the kiln body, and the heat receiving portion where the raw material inorganic material receives heat is limited to the top and bottom surfaces of the raw material inorganic material accumulated in the lower part in the kiln body, and the heat receiving area is small.
[0006]
On the other hand, the rotary kiln (Japanese Patent Laid-Open No. 7-103672) for removing the adhering matter attached to the kiln main body described above is to remove the adhering matter adhering to the inner wall of the kiln main body by stopping the operation of the rotary kiln. The deposits that adhere when the body is heated are not removed simultaneously with the heating. Since it is necessary to stop the operation of the rotary kiln and remove the deposits, the operation efficiency may be reduced.
[0007]
It is an object of the present invention to stir powder that is supplied to a cylindrical body and heated without adhering or growing on the inner wall of the cylindrical body or stirring means.
[0008]
[Means for Solving the Problems]
In order to solve the above problems, a rotary kiln of the present invention includes a rotating cylindrical body, a stirring means that rotates around a rotating shaft provided in the direction from one end of the cylindrical body to the other end, and stirs the powder. And a rotational force transmitting means for transmitting a rotational force for rotating the.
[0009]
The cylindrical body is heated by moving the powder from one end to the other end by rotating. At this time, since the rotational force transmitting means transmits the rotational force to the stirring means and rotates, the stirring means rotates around its rotation axis. The stirring means is forcibly rotated by the rotational force transmitting means, so that even if the powder adheres to the inner wall of the cylindrical body or the stirring means, the powder adhering matter is scraped off by rotation of the stirring means. Deposit growth is prevented. Therefore, the powder to be heated is uniformly heated with fewer inner portions receiving direct heat.
[0010]
Furthermore, this agitation increases the endothermic area of the entire powder and increases the endothermic rate. When the inside of the kiln becomes high temperature, the influence of radiation becomes high, so that the entire kiln is heated by radiant heat without unevenness by being thoroughly stirred.
[0011]
Moreover, it is good to transmit the rotational force by rotation of a cylindrical body to a stirring means by a rotational force transmission means. There is no need to specially provide a drive device for rotating the stirring means by rotating the stirring means using the rotation of the cylindrical body.
[0012]
Further, the rotational force transmitting means includes an internal gear provided along the inner circumferential direction of the cylindrical body, a fixed gear provided on the rotation center line of the cylindrical body, and a moving gear meshing with the internal gear and the fixed gear. Is. The rotating shaft of the stirring means is connected to the central axis of the moving gear or the central axis of another gear meshing with the moving gear.
[0013]
The internal gear is rotated by the rotation of the cylindrical body. The moving gear meshing with the internal gear and the fixed gear is rotated by the internal gear and rotates. At this time, since the moving gear meshes with the fixed gear, it rotates around the fixed gear and revolves.
[0014]
In this case, if the rotating shaft of the stirring means is connected to the central axis of the moving gear, the stirring means rotates (rotates) around the same axis as the central axis, and around the rotation center line of the cylindrical body. Rotate (revolve). When the rotating shaft of the stirring means is connected to the central axis of another gear meshing with the moving gear, the stirring means can be rotated in the direction opposite to the rotating direction of the moving gear. Furthermore, if the rotation diameter of the stirring means is brought into contact with the inner wall of the cylindrical body or the rotation diameter is determined so as to pass through the inner wall of the cylindrical body, the stirring means stirs while scraping off the adhering matter adhering to the inner wall of the cylindrical body. Further, it is more reliably prevented that the powder adheres to the inner wall of the cylindrical body and the stirring means and grows.
[0015]
Furthermore, the stirring means has any one of a screw, a plurality of sticks, a plurality of plates, a brush, and a cylinder provided along the rotation axis of the stirring means. The screw is suitable for a screw that tends to become a solid by heating because the screw itself is pulverized and stirred when the treatment itself becomes a solid during heating. The plurality of sticks are suitable for those having a high viscosity because the contact area is small and the object to be stirred is difficult to adhere. Since the plurality of plates, brushes or cylinders are continuous in the axial direction, they are suitable for heating and stirring fine particles.
[0016]
And it is good to have the expansion-contraction means extended / contracted between any one of the rotating shaft of a stirring means and a screw, a some stick, a some board, a brush, and a cylinder. By having the expansion / contraction means, it is easy to get over when a hard substance is mixed in the powder, so that the load such as force and moment applied to the stirring means is reduced.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of a rotary kiln according to the present invention will be described in detail with reference to the drawings. 1 to 9, the same or equivalent parts are denoted by the same reference numerals.
[0018]
FIG. 1 is an overall longitudinal sectional view showing a first embodiment of a rotary kiln according to the present invention. The rotary kiln according to the first embodiment heats powder to perform drying treatment or modification treatment. In particular, the powder easily adheres to the inner wall of the kiln main body that is a cylindrical body or the blade for stirring, for example, by heating, for example, It can be suitably used for powders such as resin, magnesium oxide, and calcium oxide.
[0019]
The rotary kiln includes a supply device 3 for supplying powder a, a kiln main body 7 that is a cylindrical body that receives and heats the powder a supplied from the supply device 3, and a powder heated and processed by the kiln main body 7. A discharge device 54 for discharging the body b and discharging the generated gas generated during heating. Further, the rotary kiln includes an external heating type heating means 16, for example, an electric heater, a double pipe type, a heating device that sends high-temperature steam, combustion gas, heating air, or the like between tubes, or a direct heating device such as a burner. Use.
[0020]
The supply device 3 includes a hopper 5 to which the powder a is supplied and a screw feeder 6 that sends the powder a to the kiln body 7. The screw of the screw feeder 6 is extended into the charging pipe 12 provided on the one end 8 side of the kiln main body. The screw feeder 6 is rotated and driven by the driving device 4. Although the screw feeder 6 is used for the supply apparatus 3 of 1st Embodiment, this invention is not limited to this, For example, a pusher, an air conveyance, a conveyor, a snake pump, etc. can be selected suitably and can be used. In addition, an inert gas c is supplied to the hopper 5.
[0021]
The kiln body 7 has a cylindrical shape, and is rotated and driven by a driving device 10 via a rotation mechanism provided outside the kiln body. Further, the charging pipe 12 for charging the powder a and the motor driven striking device 51 are provided on the one end 8 side of the kiln body. The striking device 51 is for peeling off deposits adhering to the wall surface by striking.
[0022]
The discharge device 54 has a discharge port 55 for discharging the processed powder b discharged from the kiln main body 7 through a valve 56 and an exhaust port 58 for discharging the generated gas d generated in the kiln main body at the lower part. . Further, a pneumatic hitting device 57 is provided below the discharge device 54, and the treated powder b adhering to the wall surface is peeled off in the same manner as the hitting device 51 of the kiln body.
[0023]
The rotary kiln of the first embodiment includes a stirring device 18 as stirring means provided in the moving direction of the powder a moving in the kiln main body 7 in addition to the above devices, and a rotational force transmitting means for rotating the stirring device 18. 37.
[0024]
The stirring device 18 rotates around a rotation shaft 30 provided in the direction 11 from one end to the other end of the cylindrical body, and the rotating tip 32 rotates along the inner wall 15 of the kiln body 7. The rotating tip 32 may rotate in contact with the inner wall 15 or may rotate along the inner wall 15 in the vicinity of the inner wall 15. The rotating shaft 30 of the stirring means is provided as one shaft from one end 8 side to the other end 9 side of the kiln main body, and in this embodiment, the discharge side extends to a support portion in the discharge device 54. This invention is not limited to this, You may provide the cantilever support in the one side of the kiln main body 7, and a some stirring means.
[0025]
The rotational force transmitting means 37 transmits the rotational force generated by the rotation of the kiln main body 7 to the stirring device 18 to forcibly rotate the stirring device 18.
[0026]
2 shows the first embodiment of FIG. 1, wherein (A) is a cross-sectional view taken along the line II of FIG. 1, and (B) is a cross-sectional view taken along the line II-II of FIG. As shown in FIG. 2 (A), the rotational force transmitting means 37 is provided on the internal gear 39 provided along the inner peripheral direction of the kiln main body 7 and the rotation center line 13 of the kiln main body 7, and the input pipe 12. And a movable gear 43 that meshes with the internal gear 39 and the fixed gear 41 and is connected to the rotating shaft 30 of the stirring means. As shown in FIG. 2B, the stirring device 18 is a stick type, and a plurality of rod-shaped members are provided radially along the rotation shaft 30. The type of agitation means is not limited to this, and is selected according to the type of powder, properties, etc., from a screw, a plurality of plates, a brush, a cylindrical body, and the like, which will be described later.
[0027]
The rotary kiln of the first embodiment having the above structure operates as follows. In FIG. 1, the powder a is supplied from one end 8 of the kiln main body 7, moved to the other end 9, heated and discharged. At this time, the rotational force transmitting means 37 transmits the rotational force generated by the rotation of the kiln main body 7 to the stirring device 18, so that the stirring device 18 is forcibly rotated by the rotational force transmitting means 37. Even if the powder adheres to the inner wall of the kiln body 7 or the stirring device 18, the stirring device 18 rotates to scrape off the powder deposits and prevent the growth of the deposits. Therefore, the powder to be heated is uniformly heated with fewer inner portions receiving direct heat. Moreover, since the rotational force transmission means 37 transmits to the stirring apparatus 18 using rotation of the kiln main body 7, it is not necessary to provide the drive device which drives the stirring apparatus 18 specially.
[0028]
As shown in FIG. 2A, when the kiln body 7 rotates in the direction of the arrow 60 (counterclockwise), the internal gear 39 inevitably rotates in the same direction, and the moving gear 43 moves in the direction of the arrow 61 (counterclockwise). While rotating in the clockwise direction, the moving gear 43 is revolved around the fixed gear 41 in the direction of the arrow 62 (counterclockwise).
[0029]
As shown in FIG. 2B, since the central shaft 44 of the moving gear is connected to the rotating shaft 30 of the stirring device, the stirring device 18 rotates in the direction of the arrow 61 (counterclockwise) while the kiln body 7 It revolves around the rotation center line 13 in the direction of the arrow 62 (counterclockwise). Therefore, the stirrer 18 stirs uniformly the adhering matter adhering to the inner wall 15 of the kiln body, and the powder a adheres to the stirrer 18 and the inner wall 15 of the kiln body 7 and does not grow. Furthermore, since the powder is well stirred, heat transfer is promoted and continuous processing is possible.
[0030]
The stirrer 18 can stir by rotating in one place only when scraping or when the amount of powder is very small, but when it is outside this condition, it changes its position while rotating and revolves. The whole powder in the kiln body can be stirred.
[0031]
3A and 3B show a second embodiment, in which FIG. 3A is a cross-sectional view illustrating a rotational force transmitting means, and FIG. 3B is a cross-sectional view illustrating a stirring device. As shown in FIG. 3A, the rotary kiln of the second embodiment is provided with a second internal gear 46 inside the moving gear 43, and further, a planetary gear 47 meshing with the second internal gear 46, a central gear ( Other gears) 49 are provided. Here, at least one of the planetary gears 47 is fixed so as to be rotatable with respect to the rotation center line 13. The rotation is applied from the second internal gear 46 by being fixed on the rotation center line 13. A central shaft 49 a of the central gear 49 is connected to the rotary shaft 30 of the stirring device 18. When the kiln body 7 rotates in the direction of the arrow 60, the internal gear 39 inevitably rotates in the same direction, causing the moving gear 43 to rotate in the direction of the arrow 61 and moving the moving gear 43 in the direction of the arrow 62. Revolve around. Further, due to the rotation of the moving gear 43, the second internal gear 46 rotates in the direction of the arrow 61, and this rotation causes the planetary gear 47 to rotate counterclockwise. As a result, the central gear 49 rotates clockwise as described below.
[0032]
As shown in FIG. 3 (B), the stirring device 18 rotates around the rotation center line 13 of the kiln body 7 while rotating (reversing) in the direction of the arrow 63, that is, the rotation direction opposite to the rotation direction of the kiln body 7. Revolve in the direction of 62. When the rotation direction of rotation is the same as that of the kiln body 7, the function of stirring is likely to be reduced because the workpiece moved beyond the rotating stirring device 18 is in a direction to escape due to rotation of the kiln body. is there. Therefore, reverse rotation is performed. Since the structure and operation of other parts in FIG. 3 are the same as those of the rotary kiln of the first embodiment shown in FIGS.
[0033]
4A and 4B show a third embodiment, in which FIG. 4A is a sectional view for explaining a rotational force transmitting means, and FIG. 4B is a simplified sectional view of FIG. As shown in FIG. 4 (A), the rotary kiln of the third embodiment rotates the stirring device in the clockwise direction, similarly to the rotary kiln of the second embodiment of FIG. The rotational force transmitting means 37 includes an internal gear 39 provided along the inner circumferential direction of the kiln main body 7, a fixed gear 41 provided on the rotation center line 13 of the kiln main body 7, and the internal gear 39 and the fixed gear 41. And a moving gear 43 that meshes. Further, there is provided a reverse gear (other gear) 50 that meshes with the moving gear 43 and is supported at a fixed distance from the moving gear 43 and the fixed gear 41. As shown in FIG. 4B, the reverse gear 50 is not meshed with the fixed gear 41 and the internal gear 39 so as to revolve (or circulate) around the fixed gear 41. In FIG. 4B, the hatched lines indicate the gear teeth.
[0034]
When the kiln body 7 rotates in the direction of arrow 60 (counterclockwise), the internal gear 39 inevitably rotates in the same direction, causing the moving gear 43 to rotate in the direction of arrow 61 and moving the moving gear 43 in the direction of arrow 62. Revolve around the fixed gear 41 in the direction. Further, the rotation of the movable gear 43 causes the reverse gear 50 to rotate in the direction of the arrow 64 (clockwise). By this rotation, the agitator 18 (not shown) rotates in the direction of the arrow 64 while rotating the center of the kiln body 7. Revolve around line 13 in the direction of arrow 62. Since the structure and operation of the other parts in FIG. 4 are the same as those of the rotary kiln of the second embodiment of FIG. 3, the description thereof is omitted.
[0035]
Next, the rotary kiln stirring device of the present invention includes any one of a screw, a plurality of sticks, a plurality of plates, a brush, and a cylinder provided along the rotation axis of the stirring device.
[0036]
5A and 5B show a fourth embodiment, in which FIG. 5A is a longitudinal sectional view of main parts of a rotational force transmitting means and a stirring device, and FIG. 5B is a sectional view taken along line III-III in FIG. The rotary kiln stirring device 18 of the fourth embodiment is a screw type. The screw 20 is suitable for the one that is easily solidified by heating because it is pulverized and stirred by the blade edge of the screw 20 when the powder itself becomes solid during heating of the powder. The structure and operation of the other parts in FIG. 5 are the same as those of the rotary kiln of the first embodiment shown in FIGS.
[0037]
6A and 6B show a fifth embodiment, in which FIG. 6A is a longitudinal sectional view of main parts of a rotational force transmitting means and a stirring device, and FIG. 6B is a sectional view taken along line IV-IV in FIG. The rotary kiln stirring device 18 of the fifth embodiment is a stick type. A plurality of sticks 22 are provided on the rotating shaft 30 of the stirring device, and a scraping member 23 for scraping powder adhering to the inner wall 15 of the kiln main body is attached to the tip. The shape of the stick 22 is a rod shape, and it is set to an appropriate shape and size such as a rod and a pipe. The scraping member 23 may have any shape as long as the scraping member 23 contacts the inner wall surface of the kiln main body or moves along the inner wall 15 in the vicinity thereof to scrape off the adhering matter attached to the inner wall 15 of the kiln main body. Shape, rod shape, etc. Since the plurality of sticks 22 have a small contact area with the powder and are difficult to adhere, the sticks 22 are suitable for those having high adhesion and high viscosity when the powder is heated. Although the stirring device 18 of 5th Embodiment shows a stick type, it is not limited to this, Even in continuous stirring parts, such as a drum and a rod, there exists an effect | action similar to the said stick. The structure and operation of the other parts in FIG. 6 are the same as those of the rotary kiln of the fourth embodiment shown in FIG.
[0038]
7A and 7B show a sixth embodiment, in which FIG. 7A is a longitudinal sectional view of main parts of a rotational force transmitting means and a stirring device, and FIG. 7B is a sectional view taken along line V-V in FIG. The rotary kiln stirring device 18 of the sixth embodiment is a plate type. As shown in FIG. 7B, a plurality of plates 24 are provided radially along the rotation shaft 30 of the stirring device. The shape of the plate 24 may be any shape as long as its tip contacts the inner wall 15 of the kiln main body or moves along the inner wall 15 in the vicinity thereof and scrapes off the adhering matter adhering to the inner wall 15 of the kiln main body. It is not limited. Since the plurality of plates 24 are continuously provided in the direction of the rotary shaft 30, the powder is suitable for heating and stirring fine particles. Although the stirring device 18 of 6th Embodiment shows a plate type, it is not limited to this, Even in continuous stirring parts, such as a brush, a drum, and a rod, there exists an effect | action similar to the said plate. The structure and operation of the other parts in FIG. 7 are the same as those of the rotary kilns of the fourth and fifth embodiments of FIGS.
[0039]
FIG. 8 is a longitudinal sectional view of one end of the rotary kiln showing the seventh embodiment. The stirring device 18 in the rotary kiln of the seventh embodiment is provided with an expansion / contraction device 34 as expansion / contraction means that expands / contracts between the rotating shaft 30 and the cylindrical body 28 of the stirring device.
[0040]
9A and 9B show the operation of the seventh embodiment, in which FIG. 9A is a cross-sectional view before overcoming a hard object, and FIG. 9B is a cross-sectional view during overcoming a hard object. When powder containing a hard material is scraped or stirred by the stirring device 18, it can be formed between the rotating shaft 30 of the stirring device and the cylindrical body 28 by, for example, a spring, a spring, metal, resin, or the like. When the powder a containing a hard material is stirred by the cylindrical body 28 by providing the expansion / contraction device 34 using a flexible member or the like, the state shown in FIG. 9A to the state shown in FIG. Thus, the cylindrical body 28 is in a state of riding on the powder a. At this time, the elastic member of the expansion device 34 is in a contracted state so that a mechanical load is not applied to the stirring device 18 itself. Here, the stirring device 18 is not limited to a cylindrical body, and an appropriate expansion / contraction device is appropriately provided between the rotating shaft 30 and the scraping / stirring member, regardless of whether the stirring device 18 is a screw, a stick, a plate, or a brush. Provide. The structure and operation of other parts in FIGS. 8 and 9 are the same as those of the rotary kiln of the first embodiment shown in FIGS.
[0041]
【The invention's effect】
According to the rotary kiln of the present invention, it is possible to stir the powder supplied to the cylindrical body and heated without adhering or growing on the inner wall of the cylindrical body or the stirring means.
[Brief description of the drawings]
FIG. 1 is an overall longitudinal sectional view showing a first embodiment of a rotary kiln according to the present invention.
2 shows the first embodiment of FIG. 1, in which (A) is a cross-sectional view taken along the line II of FIG. 1, and (B) is a cross-sectional view taken along the line II-II of FIG.
FIGS. 3A and 3B show a second embodiment, in which FIG. 3A is a cross-sectional view illustrating a rotational force transmitting means, and FIG. 3B is a cross-sectional view illustrating a stirring device;
4A and 4B show a third embodiment, in which FIG. 4A is a cross-sectional view for explaining a rotational force transmitting means, and FIG. 4B is a simplified cross-sectional view of FIG.
5A and 5B show a fourth embodiment, in which FIG. 5A is a longitudinal sectional view of a main part of a rotational force transmitting means and a stirring device, and FIG. 5B is a sectional view taken along line III-III in FIG.
6A and 6B show a fifth embodiment, wherein FIG. 6A is a longitudinal sectional view of main parts of a rotational force transmitting means and a stirring device, and FIG. 6B is a sectional view taken along line IV-IV in FIG.
7A and 7B show a sixth embodiment, in which FIG. 7A is a longitudinal sectional view of main parts of a rotational force transmitting means and a stirring device, and FIG. 7B is a sectional view taken along line VV in FIG.
FIG. 8 is a longitudinal sectional view of an essential part of one end of a rotary kiln showing a seventh embodiment.
9A and 9B show the operation of the seventh embodiment, in which FIG. 9A is a cross-sectional view before getting over, and FIG. 9B is a cross-sectional view during getting over.
[Explanation of symbols]
7 Kiln body (cylindrical body)
8 One end 9 Other end 13 Center of rotation 15 Inner wall 18 Stirring device (stirring means)
20 Screw 22 Stick 24 Plate 26 Brush 28 Cylindrical body 30 Rotating shaft 34 Telescopic device (Expanding means)
37 Rotational force transmission means 39 Internal gear 41 Fixed gear 43 Moving gear 49 Central gear (other gear)
50 Reverse gear (other gears)
a Powder

Claims (3)

A cylindrical body that rotates and moves the powder from one end to the other end and heats, and a stirring means that rotates around a rotation shaft provided in the direction from one end to the other end of the cylindrical body to stir the powder; and A rotational force transmitting means for transmitting a rotational force for rotating the stirring means,
The rotational force transmitting means includes an internal gear provided along an inner circumferential direction of the cylindrical body, a fixed gear provided on a rotation center line of the cylindrical body, and a moving gear meshing with the internal gear and the fixed gear. And the rotary shaft of the stirring means is connected to the central axis of the moving gear or the central axis of another gear meshing with the moving gear.   2. The rotary kiln according to claim 1, wherein the agitation unit includes any one of a screw, a plurality of sticks, a plurality of plates, a brush, and a cylindrical body provided along a rotation axis of the agitation unit.   3. The agitation device according to claim 2, wherein the agitation unit includes an expansion / contraction unit that expands and contracts between any one of the rotation shaft of the agitation unit and the screw, the plurality of sticks, the plurality of plates, the brush, and the cylindrical body. A rotary kiln.

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