JPH108152A - Vacuum heat treatment furnace of powdery and granular material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vacuum heat treatment furnace which can efficiently execute the heat treatment to powdery and granular material while preventing the condensation or the consolidation, and therefore, can obtain an available material from the powdery and granular material in a short time. SOLUTION: This vacuum heat treatment furnace is used to execute the heat treatment of the powdery and granular material under vacuum atmosphere in a treating chamber formed in a closed type vessel. In such a case, plural plates are arranged in many steps at a prescribed interval in the treating chamber and members 41, 44, 49 for stirring and members 51, 54, 59 for transporting are rotatably arranged so as to respectively approach the upper surface of the plate, and the powdery and granular material supplied to the plate at te uppermost step is dropped into the plate of lower step in order with the members for transporting while being stirred with the stirring member to continuously execute the heat treatment.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a furnace for vacuum heat treatment of granular material. For example, powdery and granular scrap contains impurities such as water, oil, paint, and dust in addition to the scrap main body. It is a waste of resources to directly dispose of the above-mentioned scraps containing valuables, so it is necessary to remove impurities adhering to or mixed with the scrap body, for example, the metal from such scraps and reuse the metal. Is desired. Similarly, dust captured by a dust collector in a steelmaking plant contains impurities such as lead, zinc, and dust, in addition to iron, and impurities attached to or mixed with iron from such dust. It is desirable to remove and reuse the iron. Similarly, since the mill scale generated in the rolling process of the steelmaking factory contains an oxide of a valuable metal, it is desired to react the carbon powder with the oxide to recover the valuable metal and reuse it. . The present invention relates to a vacuum heat treatment furnace for heat-treating powder or granules represented by scrap or dust as described above in a vacuum atmosphere to obtain valuable materials from the powder or granules.

[0002]

2. Description of the Related Art Granules themselves have heat insulation properties as a whole, and it is therefore difficult to obtain valuable materials from the granules simply by heat-treating the granules. Therefore, conventionally, for example, when evaporating and removing impurities in a granular material, a vacuum heat treatment furnace for heating the granular material in a vacuum atmosphere has been used. As such a vacuum heat treatment furnace, a closed vessel,
It is proposed to provide a processing chamber formed by being surrounded by a heat insulating material in the container, heating means provided in the processing chamber, and vacuum means for setting the processing chamber connected to the container to a vacuum atmosphere. (JP-A-4-225876). However, in this vacuum heat treatment furnace, since the object to be processed is heated in a stationary state, especially when the object to be processed is a granular material, even if it is performed in a vacuum atmosphere, it is difficult to evaporate and remove impurities. There is a disadvantage that it takes a long time.

Therefore, as another vacuum heat treatment furnace, a closed system container, a processing cylinder rotatably arranged in the container and lined with a heat insulating material, and a heating means inserted in the axial portion of the processing cylinder And a vacuum means connected to the container and providing a vacuum atmosphere to the inside of the processing cylinder has been proposed (JP-A-5-157455). The vacuum heat treatment furnace is heated in a vacuum atmosphere while transferring the granular material as an object to be processed while rolling in a processing cylinder to evaporate and remove impurities in the granular material. In comparison with the vacuum heat treatment furnace in which the powder is heated, the time required for evaporating and removing impurities is short. However, even in this vacuum heat treatment furnace, there is a disadvantage that it takes a long time to evaporate and remove impurities because the granular material is partially agglomerated or solidified and rolls in the processing cylinder. is there.

[0004]

The problem to be solved by the present invention is that in the conventional vacuum heat treatment furnace, it takes a long time to obtain a valuable material from the granular material.

[0005]

SUMMARY OF THE INVENTION Accordingly, the present invention is a vacuum heat treatment furnace for heat-treating a granular material under a vacuum atmosphere in a processing chamber formed in a closed vessel, wherein a plurality of plates are provided in the processing chamber. Are arranged in multiple stages at predetermined intervals, and a stirring member and a transfer member are rotatably arranged near the upper surface of each of the plates, and the powder and granules supplied to the uppermost plate are separated from each other. The present invention relates to a vacuum heat treatment furnace for powdery and granular materials, characterized in that the powder is sequentially dropped onto a lower plate by the transfer member and is continuously heat-treated while being stirred by the stirring member.

[0006] In the vacuum heat treatment furnace for powders and granules according to the present invention, similarly to the above-mentioned conventional vacuum heat treatment furnace, a closed vessel and a treatment chamber formed by being surrounded by a heat insulating material in the vessel are provided. Normally, there are provided heating means provided in the processing chamber and vacuum means for bringing the processing chamber connected to the container into a vacuum atmosphere.

[0007] In the vacuum heat treatment furnace for powders and granules according to the present invention,
A plurality of plates are arranged in the processing chamber in multiple stages at predetermined intervals. A plurality of plates can be arranged in a disk shape having the same diameter around the same axis, and in this case, each plate is provided with an opening for dropping a powdery material. Also, the plurality of plates may be arranged in a step shape as a whole with a disk shape having the same diameter, and in this case also, each plate is provided with an opening for dropping powder particles, but the lowermost stage is provided. Except for the plate, the opening of each plate is sequentially provided at a position facing the lower plate. As will be described later, the granules are stirred on the plate by the stirring member and simultaneously extruded while being spread thinly by the transfer member, and sequentially dropped from the opening of the plate to the lower plate,
The opening is preferably in the form of a slit along the radial direction of each plate, and a ring-shaped wall piece is erected on the periphery of each plate to prevent powder particles from falling from the periphery of the plate. Is preferred.

A plurality of plates may be arranged in a disk shape having a large diameter in order toward the lower stage around the same axis. In this case as well, each plate is provided with an opening for dropping a powdery material. It can be provided, but in this case, it is not necessary to provide such an opening. This is because, as will be described later, the powders and granules charged in the uppermost plate can be sequentially dropped from the peripheral edge to the lower plate.

Further, in the vacuum heat treatment furnace for granular material according to the present invention, the stirring member and the transfer member are rotatably arranged near the upper surfaces of the plurality of plates. The agitating member is for agitating the granules on the plate to prevent the coagulation or consolidation, and the transferring member is to extrude the granules on the plate while spreading them thinly and sequentially to the lower plate. And to drop it. A comb-shaped member having a plurality of protrusion bars or protrusions can be used as the stirring member, and a straight or arc-shaped blade can be used as the transfer member. When the powder is dropped from the peripheral edge of the plate to the lower plate sequentially, it is preferable to use a blade that is inclined or curved in a direction opposite to the rotation direction as the transfer member.

The powdery material is agitated on each plate by a stirring member and simultaneously extruded while being spread thinly by a transfer member. When each plate has an opening, the lower portion is sequentially placed in a lower stage from the opening. If the plate does not have an opening, it falls sequentially from its periphery to the lower plate. The granular material is heat-treated in a vacuum atmosphere while being repeatedly stirred and thinly spread on each of the multi-stage plates from the uppermost plate to the lowermost plate. Therefore, according to the present invention, the granular material does not solidify or solidify during the heat treatment, and the granular material can be heat-treated in a short time. For example,
When the particles are heated in a vacuum atmosphere to remove impurities contained in the particles by evaporation, the impurities can be removed by evaporation in a short time.

In a vacuum heat treatment furnace in which multi-stage plates are arranged around the same axis, in order to more effectively prevent the coagulation or consolidation of the granular material on each plate, each stirring member and each transfer member are required. Are preferably arranged around the same axis as these plates, and the stirring member and the transfer member are intermittently rotated in the forward direction as a whole while rotating in the forward and reverse directions. In particular, the transfer member is intermittently rotated in the forward direction as a whole while the transfer member is rotated in the forward and reverse directions, and the stirring member is also intermittently rotated at a time difference from the forward rotation of the transfer member. It is preferable to make the rotation in the positive direction.

Further, in a vacuum heat treatment furnace in which multi-stage plates are arranged stepwise as a whole, in order to more effectively prevent coagulation or consolidation of the granular material on each plate, a stirring member is provided for each plate. Preferably, the transfer member is disposed around the same axis as the plate, and the stirring member and the transfer member are intermittently rotated in the forward direction as a whole while rotating in the forward and reverse directions. In particular, the transfer member is intermittently rotated in the forward direction as a whole while the transfer member is rotated in the forward and reverse directions, and the stirring member is also intermittently rotated at a time difference from the forward rotation of the transfer member. It is preferable to make the rotation in the positive direction.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an overall front view illustrating a vacuum heat treatment furnace according to the present invention in a partial longitudinal section, FIG. 2 is a partially enlarged longitudinal sectional view showing an internal structure of the same vacuum heat treatment furnace as FIG. FIG.
1 is a partially enlarged horizontal sectional view showing the same internal structure of the vacuum heat treatment furnace as FIG. 1, and FIG. 4 is a partially enlarged vertical sectional view showing the same internal structure of the vacuum heat treatment furnace as FIG. In FIG. 1, a heat insulating material 12 is placed in a cylindrical closed container 11 as a whole.
A processing chamber 13 surrounded by a heat insulating material 12 is formed in the container 11, and the processing chamber 13 is provided with heaters 14 and 15. A rotary shaft 21 is mounted on the axis of the container 11 so as to penetrate the heat insulating material 12 and the processing chamber 13. The rotary shaft 21 is connected to a drive shaft (not shown) of a drive motor 21 a attached to the container 11. I have.

In the processing chamber 13, plates 31 to 39 are arranged at predetermined intervals in a total of nine steps in the vertical direction. The plates 31 to 39 are formed in a disk shape having the same diameter, The bearing is supported by the rotating shaft 21 at the portion. The disc-shaped plates 31 to 39 having the same diameter are arranged around the same axis. Ring-shaped wall pieces 31a, 34a, 39a,... Are erected on the periphery of the plates 31 to 39, and the wall pieces 31a, 34a, 39a,.
Is mounted on a bar 21b mounted vertically in the container 11. Therefore, the plates 31 to 39 are
1, but does not rotate even if the rotating shaft 21 rotates.

The plates 31 to 39 have openings 31b, 3
4b, 39b,... Are provided in a slit shape along the radial direction. The openings 31b, 34b, 39b,.
.. from top plate 31 to bottom plate 39
, Are sequentially provided at positions shifted in the direction opposite to the rotation direction of the rotating shaft 21. 2 and 3,
The rotation shaft 21 rotates clockwise when viewed from the plane, but the opening 31 b of the uppermost plate 31 is provided at a position counterclockwise from immediately below the supply pipe 61 of the granular material facing the plate 31, The opening (not shown) of the second stage plate 32 is provided at a position further counterclockwise than the opening of the top stage plate 31. Similarly, the third stage plate 3
From 3 to the lowermost plate 39, these openings are sequentially provided at leftwardly shifted positions. Of these, the opening 34b of the fourth plate 34 is provided at the rightmost position. Opening 3 of the lowermost plate 39
9b is provided on the leftmost side, and the opening 39b is located immediately above the discharge chute 71 formed in a funnel shape.

In FIG. 2 to FIG.
Are arranged on the upper surfaces of 4, 39,... Provided with two comb-like objects having a plurality of projecting bars, respectively. Transfer members 51, 5 each having two blades at a position slightly clockwise from stirring members 41, 44, 49,...
4, 59,... Are arranged. Stirring member 41,
44, 49,... And transfer members 51, 54, 59,
Are attached to the rotating shaft 21 and rotate integrally with the rotating shaft 21. For example,
When the rotating shaft 21 is rotated intermittently in the forward direction as a whole while rotating the rotating shaft 21 in the forward and reverse directions, that is, the rotating shaft 21 is intermittently rotated in the clockwise direction as a whole while alternately rotating clockwise and counterclockwise. When rotated, the stirring members 41, 44, 4
, And the transfer members 51, 54, 59,... Also intermittently rotate in the forward direction as a whole while rotating in the forward and reverse directions, that is, the stirring members 41, 44, 49,.・
The transfer members 51, 54, 59,... Also rotate clockwise and counterclockwise alternately and rotate intermittently clockwise as a whole.

A supply pipe 61 is inserted into the processing chamber 13 so as to face the uppermost plate 31 directly below. The supply pipe 61 provided with a valve 62 is connected to a hopper 63.
On the upstream side of the hopper 63, a supply pipe 6 with a valve 64 interposed
5 is connected. A funnel-shaped discharge chute 71 is arranged in the processing chamber 13 with the opening 39b of the lowermost plate 39 facing directly above. The discharge chute 71 is connected to a discharge pipe 73 through which a valve 72 is interposed. The discharge pipe 73 is connected to a hopper 74.
A discharge pipe 76 having a valve 75 interposed is connected to the downstream side.

Although not shown, the processing chamber 1 is
A vacuum pump for making 3 a vacuum atmosphere is connected, and a condenser is interposed between the container 11 and the vacuum pump. This vacuum pump is also connected to hoppers 63 and 74.

A case will be described in which the vacuum heat treatment furnace according to the present invention described with reference to FIGS. 1 to 4 is used to heat a granular material in a vacuum atmosphere to evaporate and remove impurities in the granular material. With the valve 64 opened and the valve 62 closed, the powder is charged into the hopper 63. Valves 64, 62, 75
With the valve 72 closed, the vacuum pump is operated to bring the processing chamber 13 and the hoppers 63 and 74 into a vacuum atmosphere, and the drive motor 21 a and the heaters 14 and 1.
Activate 5 When the temperature inside the processing chamber 13 reaches a predetermined temperature, the valve 62 is opened, and the powdery material is dropped from the hopper 63 to the uppermost plate 31. The dropped particles are agitated by the agitation member 41 on the plate 31 and simultaneously extruded while being thinly spread by the transfer member 51, and fall from the opening 31 b of the plate 31 to the second stage plate 32. The dropped particles are similarly agitated on the plate 32 and simultaneously extruded while being spread thinly.
To fall. In the same manner as described above, the granular material sequentially falls onto the lower plate, and finally falls from the opening 39b of the lowermost plate 39 to the discharge chute 71. The powder is repeatedly stirred by the stirring members 41, 44, 49,... On the respective upper surfaces of the nine-stage plates 31 to 39, and simultaneously thinned by the transfer members 51, 54, 59,. Since the particles are spread and heated under a vacuum atmosphere in such a state, the particles do not coagulate or solidify. Therefore, impurities in the particles are extremely efficiently,
It is evaporated off in a short time. After the powdery material, which is the processing object dropped on the discharge chute 71, is stored in the hopper 74, the valve 72 is closed, and the pressure inside the hopper 74 is restored.
Open and take out.

FIG. 5 is a partially enlarged transverse sectional view showing the internal structure of another vacuum heat treatment furnace according to the present invention, and FIG. 6 is a partially enlarged vertical sectional view showing the same internal structure of the vacuum heat treatment furnace as FIG. The other configurations, the description of which is omitted, are the same as those illustrated in FIGS. 1 to 4. However, in FIGS. 5 and 6, the stirring member rotates with a time lag from the transfer member. ing. On the upper surface of the plate 81, a stirring member 91 having two combs 91a and 91b each having a plurality of projecting rods is arranged close to the plate 81, and the stirring member 9 is provided.
Two blades 100a, 100b in a slightly clockwise position of 1
Is disposed.

The transfer member 100 includes a slightly thick cylindrical piece 100c attached to the rotating shaft 22, and two blades 100a and 100b extending from the cylindrical piece 100c. A hollow portion 100d is formed in the peripheral portion, and substantially fan-shaped openings 100e and 100f communicating with the hollow portion 100d are formed in the outer peripheral portion of the cylindrical piece 100c. Therefore, the transfer member 100 rotates integrally with the rotating shaft 22.

On the other hand, the stirring member 91 includes a ring-shaped bearing 91c engaged with the rotating shaft 22, a ring piece 91d attached to the outer periphery of the bearing 91c, and comb-like members 91a and 91b extended from the ring piece 91d. The bearing 91c and the ring piece 91d are accommodated in the hollow portion 100d of the cylindrical piece 100c, and the comb-like objects 91a and 91b extend from the ring piece 91d through the openings 100e and 100f of the cylindrical piece 100c. Has been established. Therefore, the stirring member 91 is connected to the rotating shaft 2.
2, and rotates only with the transfer member 100 when the combs 91a, 91b are in contact with the end faces of the openings 100e, 100f of the tubular piece 100c.

For example, when the opening angle of the substantially fan-shaped openings 100e and 100f formed in the cylindrical piece 100c is θ, the rotation shaft 22 rotates clockwise by 2θ and then rotates counterclockwise by 1θ. By repeating the forward and reverse rotation,
The transfer member 100 also rotates in the forward and reverse directions integrally with this, and as a result, the transfer member 100 rotates clockwise by 1θ. On the other hand, under the condition of repeated rotation of the transfer member 100 as described above, the transfer member 100
When rotating clockwise by the amount of 1 minute, the first 1θ
Since the stirring members 91 do not rotate because the members 1a and 91b play inside the openings 100e and 100f, the combs 91a and 91b abut the end surfaces of the openings 100e and 100f by 1θ for stirring. The member 91 rotates clockwise together with the transfer member 100. And if the transfer member 100 is 1
When rotating counterclockwise by θ, this 1θ corresponds to the comb-like object 9.
The agitating member 91 does not rotate because 1a and 91b play in the openings 100e and 100f. After all, in this case, if the transfer member 100 is rotated intermittently in the forward direction as a whole while being rotated in the forward and reverse directions, the stirring member 91 will have a time difference from the rotation of the transfer member 100 in the forward direction. And intermittently rotate in the positive direction.

FIG. 7 is a partial front view showing the arrangement of plates in still another vacuum heat treatment furnace according to the present invention.
Other configurations whose description is omitted are the same as those illustrated in FIGS. 1 to 4, but in FIG. 7, disk-shaped plates 111, 112, and 113 having a large diameter sequentially toward the lower stage are entirely formed. Are arranged in a conical shape,
112 and 113 are supported on the same rotating shaft 23,
No ring-shaped wall pieces are erected on these edges.
These peripheral edges are respectively different from the bar members 111b, 112.
b, 113b. In FIG. 7, no openings are provided in the plates 111, 112 and 113, and
The granular material falls from the periphery of these plates to the lower plate sequentially. Therefore, in FIG. 7, in order to make the falling of the granular material smooth, it is preferable to use a transfer member having a blade that is inclined or curved in a direction opposite to the rotation direction when viewed from a plane, and As the discharge chute, a large-sized discharge chute that directly faces the periphery of the lowermost plate is used.

FIG. 8 is a partial front view showing the arrangement of plates in still another vacuum heat treatment furnace according to the present invention. Other configurations for which description is omitted are the same as those illustrated in FIGS. 1 to 4 for each plate, but in FIG. 8, disc-shaped plates 121, 122, and 123 having the same diameter.
Are arranged stepwise as a whole, and the plate 12
1, 122 and 123 are different rotating shafts 24 and 2 respectively.
5 and 26, and the ring-shaped wall pieces erected on these peripheral edges also have different rod members 121b and 122, respectively.
b, 123b. In FIG. 8, the opening of the plate 121 is opened at a position facing the plate 122 directly below, and the opening of the plate 122 is opened at a position facing the plate 123 directly below. From the bottom to the lower plate.

[0026]

As is apparent from the above description, the present invention described above can efficiently heat-treat a granular material while preventing coagulation or consolidation of the granular material during the heat treatment. There is an effect that valuable resources can be obtained in a short time.

[Brief description of the drawings]

FIG. 1 is an overall front view illustrating a vacuum heat treatment furnace according to the present invention in a partial longitudinal section.

FIG. 2 is a partially enlarged longitudinal sectional view showing the same internal structure of the vacuum heat treatment furnace as FIG.

FIG. 3 is a partially enlarged cross-sectional view showing the same internal structure of the vacuum heat treatment furnace as in FIG.

FIG. 4 is a partially enlarged longitudinal sectional view showing the same internal structure of the vacuum heat treatment furnace as FIG. 1 from another angle.

FIG. 5 is a partially enlarged transverse sectional view showing the internal structure of another vacuum heat treatment furnace according to the present invention.

FIG. 6 is a partially enlarged longitudinal sectional view showing the internal structure of the same vacuum heat treatment furnace as in FIG.

FIG. 7 is a partial front view showing the arrangement of plates in still another vacuum heat treatment furnace according to the present invention.

FIG. 8 is a partial front view showing the arrangement of plates in still another vacuum heat treatment furnace according to the present invention.

[Explanation of symbols]

11: container, 12: heat insulating material, 13: processing chamber, 21 to 26: rotating shaft, 31 to 39, 81, 11
1 to 113, 121 to 123 ... plate, 31b,
34b, 39b ... openings, 41, 44, 49, 91
... Stirring member, 51, 54, 59, 100 ... Transfer member, 63, 74 ... Hopper

Claims (8)

[Claims] 1. A vacuum heat treatment furnace for heat-treating a granular material under a vacuum atmosphere in a treatment chamber formed in a closed vessel, wherein a plurality of plates are arranged in a plurality of stages at predetermined intervals in the treatment chamber. A stirring member and a transfer member are rotatably arranged in proximity to the respective upper surfaces of the plates, and the transfer is performed while stirring the particles supplied to the uppermost plate by the stirring member. A vacuum heat treatment furnace for powders and granules, characterized in that the powder is sequentially dropped onto a lower plate by a member for heat treatment to be continuously heat treated. 2. The vacuum heat treatment furnace for granular material according to claim 1, wherein a plurality of plates are arranged around the same axis, and each of the plates is provided with an opening for dropping the granular material. 3. The vacuum heat treatment furnace for powdery and granular materials according to claim 1, wherein a plurality of plates having larger diameters are sequentially arranged around the same axis toward the lower stage. 4. A stirring member and a transfer member are arranged around the same axis as a plurality of plates, and the stirring member and the transfer member are intermittently rotated as a whole while being rotated in forward and reverse directions. 4. The vacuum heat treatment furnace for a granular material according to claim 2, wherein the furnace is rotated in a positive direction. 5. Each stirring member and each transfer member are arranged around the same axis with the plurality of plates, and the transfer member is intermittently rotated in the forward direction as a whole while rotating the transfer member in the forward and reverse directions. 4. A vacuum heat treatment furnace for granular material according to claim 2, wherein the stirring member is intermittently rotated in the positive direction with a time lag from the rotation of the transfer member in the positive direction. . 6. The vacuum heat treatment furnace for granular materials according to claim 1, wherein the plurality of plates are arranged in a stepped shape as a whole, and each of the plates is provided with an opening for dropping the granular materials. 7. A stirring member and a transfer member are disposed around the same axis as the plate for each plate, and the stirring member and the transfer member are intermittently rotated as a whole while rotating in the forward and reverse directions. 7. The vacuum heat treatment furnace for a granular material according to claim 6, wherein the furnace is rotated in a positive direction. 8. A stirring member and a transfer member are arranged around the same axis as the plate for each plate, and the transfer member is intermittently moved in the forward direction as a whole while rotating the transfer member in the forward and reverse directions. 7. The vacuum heat treatment furnace for granular material according to claim 6, wherein the stirring member is rotated intermittently in the positive direction with a time difference from the rotation of the transfer member in the positive direction.