JP2012102901A - Rotary furnace - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotary furnace having superior thermal efficiency and capable of suppressing consumption of a heater.SOLUTION: The rotary furnace 1 includes: a solid rotating pipe 3 that can rotate; a heater installation space 15 provided inside the rotating pipe 3 to include the rotation center axis 53 of the rotating pipe 3; a resistance-heating type heater arranged in the heater installation space 15 to include the rotation center axis 53; and a particle reaction space 14 which is provided in the periphery of the heater installation space 15 along the rotation center axis 53, and to which raw material particles 16 are to be charged. In a heat treatment, heat generated from the heater is transferred from the inner wall of the heater installation space 15 through the rotating pipe 3 to heat the inner wall of the particle reaction space 14. The raw material particles 16 charged to the particle reaction space 14 are heat-treated by the heat of the inner wall of the particle reaction space 14.

Description

  The present invention relates to a rotary furnace.

  The rotary furnace is a furnace having a structure in which heat treatment is performed while moving the material to be heat-treated in the inclined rotating tube by the rotational motion of the rotating tube and the frictional force and gravity between the material to be heat-treated and the rotating tube.

  The rotary furnace has an advantage that continuous processing is possible and uniform heat treatment is possible, compared with a pusher furnace which is a furnace in which a base plate on which an object to be heat-treated is moved by a pusher.

  When the rotary furnace is roughly classified according to the position of the heating unit, it is divided into a structure in which the heating unit is inside the rotary tube (referred to as an internal heating type) and a structure outside the rotary tube (referred to as an external heating type).

  As a specific structure of the former rotary furnace, there is a structure in which a heating part such as a resistance heating type heater is disposed inside the rotary furnace and the object to be heat-treated is mainly heated by radiant heat (Patent Document 1).

  As a specific structure of the latter rotary furnace, there is one that heats an object to be heat-treated by flowing a gas heated outside the rotary tube into the rotary tube (Patent Document 2, Patent Document 3, and Patent Document 4). ).

  Further, an external heating type structure in which a heating unit is disposed outside the rotary tube is also known (Patent Document 5).

JP 2000-72429 A Japanese Utility Model Publication No. 02-106593 JP-A-11-193987 JP 2001-11467 A JP 2000-161859 A

  However, the above structure has the following problems.

  First, as in Patent Document 1, in the case of a structure in which a resistance heating type heater is disposed inside a rotary furnace and the object to be heat-treated is mainly heated by radiant heat, for example, the object to be heat-treated is Al, W, Ti, V, Cr In some cases, it is a mixture of a metal oxide such as Zr and carbon.

  When performing reductive carbonization, reductive nitriding or reductive carbonitriding on such a mixture, it is necessary to heat the rotary furnace to a high temperature of 1200 ° C. or higher, and in some cases 2000 ° C. in an atmosphere such as hydrogen or nitrogen. The material of the heater and the rotating tube may be graphite.

At this time, gas containing oxygen (O) such as water (H ₂ O) or carbon dioxide such as CO or CO ₂ is generated by reduction of the oxide. For this reason, in the high temperature range, graphite and water and CO ₂ constituting the heater and the rotating tube form stable CO, resulting in local consumption of graphite, operation at a stable heating temperature and continuous operation of heat treatment. There was a problem that could not be.

  On the other hand, in the structure described in Patent Documents 2 to 4, in which the atmospheric gas is heated outside the reaction zone and the heated gas is flowed, it is possible to suppress the consumption of the heater part, but the structure using the resistance heating heater and There was a problem that thermal efficiency was inferior compared with it.

  In addition, due to the property of using heated gas, a heat-resistant structure is also required for the piping through which the gas flows, so that there is a problem that it is difficult to raise the heating temperature as compared with the resistance heating type heater.

  Furthermore, in the external heating type structure in which the heating unit is disposed outside the rotary tube as shown in Patent Document 5, although the consumption of the heater can be suppressed, the heat energy is consumed other than the outer wall of the rotary tube. However, there is a problem that the thermal efficiency is deteriorated as compared with the internal heat type structure.

  In addition, as compared with the internal heat type structure, there is a problem that an outer frame such as a heat insulating material for protecting the heating portion becomes large and the furnace becomes large.

  The present invention has been made in view of the above-described problems, and a technical problem thereof is to provide a rotary furnace that is more excellent in thermal efficiency than conventional ones and can suppress heater consumption.

  In order to solve the above-described problems, the present invention includes a rotatable solid rotating body, a heating space provided inside the rotating body so as to include a rotation center axis of the rotating body, and the rotating A resistance heating type heater disposed in the heating space so as to include a central axis; and a heat treatment space provided around the heating space along the rotational central axis and into which an object to be heat-treated is charged. And a rotary furnace characterized by comprising:

  In the present invention, it is possible to provide a rotary furnace that is superior in heat efficiency than the conventional one, can suppress the consumption of the heater, and can be easily operated continuously.

It is a side basic structure figure showing rotary furnace 1 of the present invention, and fixed pipe 2 and heat insulating material 7 are indicated with a sectional view. It is sectional drawing which shows the detail of the rotating tube 3 of FIG. 1, and its surrounding structure. It is sectional drawing which shows the detail of the rotary tube 3a of the rotary furnace 1a based on a prior art, and the structure of the circumference | surroundings. It is AA sectional drawing of the rotary tube 3 and the center heater 4 of FIG. It is BB sectional drawing of the rotary tube 3a and the center heater 4 of FIG. It is an enlarged view which shows the modification of the raw material injection opening 6 vicinity of FIG. 2, Comprising: (a) is sectional drawing parallel to an axial direction, (b) is CC sectional drawing of (a). It is an enlarged view which shows the modification of the raw material inlet 6 vicinity of FIG. 2, Comprising: (a) is sectional drawing parallel to an axial direction, (b) is DD sectional drawing of (a).

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, exemplary embodiments suitable for the invention will be described in detail with reference to the drawings.

  First, a schematic configuration of the rotary furnace 1 according to the present embodiment will be described with reference to FIGS. 1, 2, and 4.

  As shown in FIGS. 1, 2, and 4, the rotary furnace 1 is rotatably provided, and a heater installation space 15 (heating space) in which a resistance heating type heater 29 for heating is disposed, and A solid rotary tube 3 having a particle reaction space 14 (heat treatment space) through which raw material particles 16 as a heat treatment object pass is provided as a rotating body.

  In FIG. 1, the rotary tube 3 is provided with its rotation center axis 53 inclined with respect to the horizontal plane 55, and the inclination angle α is adjusted to a predetermined angle by the inclination angle adjusting mechanism 28.

  The rotary furnace 1 is also provided around the heater 29 and the rotary tube 3 disposed in the heater installation space 15. The rotary furnace 1 is provided around the fixed tube 2 and the fixed tube 2 that hold the rotary tube 3. Is provided on the upper end side of the rotary tube 3 (the end surface located on the upper side in an inclined state). , A raw material container 21 for storing and supplying the raw material particles 16, a raw material input port 6 for introducing the raw material particles 16 into the rotary tube 3, and a lower end side of the rotary tube 3 (inclined state of both end faces) And a product container 22 for recovering the heat-treated reaction particles 17.

  Furthermore, electrodes 25 are provided at both ends of the heater 29, and the electrodes 25 are connected to a power source 26.

  The rotary furnace 1 is provided on the lower end side of the rotary tube 3, and includes an atmosphere gas supply port 27 that supplies atmospheric gas into the heater installation space 15 and the particle reaction space 14 of the rotary tube 3, and the upper end of the rotary tube 3. And a non-contact temperature measuring device 9 for measuring the temperature of the rotary tube 3 and an exhaust port 24 for exhausting atmospheric gas and reaction gas.

  In FIG. 1, an exhaust port for replacing the heat treatment atmosphere is omitted.

  Next, with reference to FIGS. 1-7, each component of the rotary furnace 1 is demonstrated in detail.

  The rotating tube 3 is a member that heats the raw material particles 16 to generate the reaction particles 17, and a heater provided through the rotating tube 3 so as to include the rotation center shaft 53 at the center. There is an installation space 15, and a heater 29 is disposed in the heater installation space 15.

  The ends (open ends) on both sides of the heater installation space 15 are made of graphite or the like so that the gas generated when the raw material particles 16 react with the heater 29 inside the rotary tube 3 does not contact. A heater space atmosphere protection ring 13 is provided. Since both ends of the heater 29 are heated at a lower temperature than the central portion because of resistance heating and react with the gas generated by the heat treatment and local exhaustion is unlikely to occur, the heater space atmosphere protection ring 13 has a heater installation space 15. Are arranged at both ends.

  The rotary tube 3 also has a heat treatment space provided through the rotary tube 3 along the rotation center axis 53, that is, a particle reaction space 14 around the heater installation space 15.

  As will be described in detail later, when the raw material particles 16 introduced into the rotary tube 3 from the raw material container 21 through the raw material inlet 6 pass through the particle reaction space 14, the heat and atmosphere of the rotary tube 3 heated by the heater 29. The raw material particles 16 are heat-reacted by the action of the atmospheric gas supplied from the gas supply port 27 into the particle reaction space 14.

  1, 2, and 4, since the rotary tube 3 is a cylinder, the hollow portion of the cylinder constitutes a heater installation space 15, and the particle reaction space 14 is formed in the thick portion of the cylinder. Yes.

  Here, it is desirable that the particle reaction spaces 14 are equally arranged around the heater installation space 15 so that the distances from the rotation center axis 53 are equal.

  Further, it is desirable that the particle reaction space 14 has the same axial cross-sectional shape (cross-sectional shape perpendicular to the axial direction).

  In FIG. 4, the particle reaction space 14 has a circular axial cross-sectional shape, but is not necessarily limited to a circular shape, and may be, for example, a polygonal or star-shaped hole.

  However, when the inner wall of the particle reaction space 14 in contact with the raw material particles 16 is composed of a material that reacts with the raw material particles 16 and is consumed, the axial cross-sectional shape is unlikely to change even after being treated for a long time. It is desirable to be a thing.

  Specifically, as the axial cross-sectional shape, a circular shape in which the flowability and residence time of the object to be heat-treated is difficult to change is desirable.

  Although details will be described later, the heater installation space 15 and the particle reaction space 14 are separately provided in the rotary tube 3 as described above, and the raw material particles 16 are mainly transmitted by heat conduction from the inner wall of the particle reaction space 14. Heating the heater 29 so that it does not come into contact with the raw material particles 16, the reactive particles 17, and the gas generated by the reaction can prevent the heater 29 from being consumed during the heat treatment, enabling continuous processing and the raw material particles 16. Can be heated uniformly.

  When the material constituting the rotary tube 3 is heated at a high temperature of 1200 ° C. or higher, for example, graphite excellent in workability and heat resistance is mentioned, but when the heating temperature is lower than this, stainless steel or the like may be used, What is necessary is just to select suitably also considering the impurity mixing in to-be-processed material.

  As described above, the heater 29 is a resistance heating type heater. As shown in FIG. 2, the central portion constitutes the central heater 4, and both ends are larger in diameter than the central heater 4 and are connected to the electrode 25. The part heater 5 is comprised.

  The heater 29 is disposed so as to include the rotation center shaft 53. In FIG. 4, the center axis of the heater 29 (central heater 4) and the rotation center axis 53 of the rotary tube 3 coincide with each other. However, if the rotation center axis 53 is included in the heater 29, the center of the heater 29. An eccentric arrangement in which the shaft and the rotation center shaft 53 do not coincide with each other may be employed.

  2 illustrates the heater 29 having one central heater 4 and two end heaters 5, but may have a combination of three or more.

  Further, as described above, since the heater 29 is a resistance heating type heater, the electrode 25 connected to the end heater 5 communicates with the power source 26.

  That is, when current is passed through the heater 29 via the electrodes 25 at both ends of the heater 29 using the power source 26, the heater 29 is heated by resistance.

  At this time, the temperature of the heater 29 can be arbitrarily set by controlling the current and voltage using the power supply 26.

  The temperature of the heater 29, that is, the temperature distribution in the reaction zone, can be arbitrarily changed not only by controlling the current and voltage but also by the diameter of the central heater 4.

  Specifically, the entire central heater 4 is not made to have the same diameter, but a range in which a high temperature is desired may be formed to have a smaller diameter than other portions.

  The material of the heater 29 may be graphite with good workability, but is not necessarily limited to graphite as long as the raw material particles 16 can be heated to a necessary temperature range by resistance heating by energization.

  Moreover, the material which comprises the electrode 25 should just be able to obtain electricity, for example, Cu etc. are used.

  Further, as shown in FIG. 2, a heater space gas supply hole 12 is provided in an end of the central heater 4 on the lower end side of the rotary tube 3.

  The heater space gas supply hole 12 is a hole for supplying an atmosphere gas for preventing the heater 29 from being consumed to the heater installation space 15, and one end thereof is disposed in the heater installation space 15 (the central heater 4 Through the side surface, and the other end passes through the side surface (of the central heater 4) disposed outside the heater installation space 15, and is heated via an insulator ring 11 attached to the central heater 4. It communicates with the space gas supply nozzle 10 (supply means).

  The heater space gas supply nozzle 10 is a pipe made of stainless steel, Cu, or the like, and the atmospheric gas is supplied from the atmospheric gas supply port 27. In FIG. 1, the atmosphere gas supply port 27 is provided at one location, but the atmosphere gas supply port 27 supplied to the particle reaction space 14 and the heater space gas supply nozzle 10 supplied to the heater installation space 15 have different flow rates. Actually, there are several so that you can do it. The gas supplied to the heater installation space 15 may be the same as the atmosphere of the object to be heat-treated, or may be other gas as long as it prevents the heater 29 from being consumed.

  The insulator ring 11 is made of a material having a high melting point that is insulative and difficult to melt in consideration of conduction when a nozzle that supplies atmospheric gas to the heater installation space 15 is in contact with the heater 29 that is energized and heated. Use things.

Examples of such a material include boron nitride (BN) having a melting point of about 2700 ° C. and alumina (Al ₂ O ₃ ) having a melting point of about 2050 ° C.

  The atmosphere gas supplied to the heater installation space 15 is discharged from the gap between the heater space atmosphere protection ring 13 and the heater 29 and is discharged to the outside through the exhaust port 24.

  The fixed tube 2 is a member that supports and fixes the rotating tube 3.

  In FIG. 1 and FIG. 2, the fixed tube 2 is a cylindrical tube, but may have any shape as long as the rotating tube 3 can be supported and fixed. The fixed tube 2 may be composed of a plurality of members.

  As a material constituting the fixed tube 2, when the rotating tube 3 is heated at a high temperature of 1200 ° C. or higher, for example, graphite excellent in workability and heat resistance can be cited, but when the heating temperature is lower than this, stainless steel or the like is used. It may be used.

  The heat insulating material 7 is a member that prevents heat escape and increases the thermal efficiency by being disposed around the fixed tube 2.

  Specific materials for the heat insulating material 7 include bricks and hollow particles mainly composed of alumina, but are not necessarily limited thereto.

  Although not shown in FIG. 1, in order to further increase the thermal efficiency, it is desirable to dispose the heat insulating material 7 also in the entire furnace body.

  The drive mechanism 37 is a member that rotates the rotary tube 3, and includes a motor 39 and a first gear 41 coupled to a rotation shaft (not shown) of the motor 39.

  In FIG. 1, a second gear 43 that meshes with the first gear 41 is disposed on the outer periphery of the rotary tube 3, and the motor 39 is operated at a predetermined speed with the first gear 41 and the second gear 43 meshing with each other. The rotating tube 3 can be rotated at a predetermined rotation speed.

  The tilt angle adjusting mechanism 28 is a member such as a hydraulic jack that adjusts the tilt angle α of the rotary tube 3 and can arbitrarily change the residence time of the raw material particles 16 in the rotary tube 3 by adjusting the tilt angle α. Is possible.

  That is, the residence time of the raw material particles 16 becomes shorter as the inclination angle α is increased, and the residence time of the raw material particles 16 becomes longer as the inclination angle α is reduced.

  The non-contact type temperature measuring device 9 is a device that measures the temperature of the rotary tube 3. For example, the radiation temperature is a thermometer that measures the temperature of an object by measuring the intensity of infrared or visible light emitted from the object. Use the total.

  As a more specific example of the non-contact temperature measuring device 9, CHINO model number FL2NNO3 having a measuring range of 1000 to 2000 ° C. can be cited.

  The temperature measurement by the non-contact type temperature measuring device 9 is a method of measuring the temperature in the rotary tube 3 directly from the inlet or outlet direction of the raw material particles 16 of the rotary tube 3. 2, the temperature inside the rotary tube 3 is measured by measuring the outer wall temperature of the rotary tube 3 through the temperature measuring port 8 from the side surface of the rotary furnace 1 as shown in FIG. The method is preferred.

  In addition, when measuring temperature from the furnace body side surface, the number of measurement points may be one or plural.

  Further, the non-contact temperature measuring device 9 may be connected to the power source 26 and the temperature measured by the non-contact temperature measuring device 9 may be fed back so that the power source 26 performs control such as temperature increase or decrease. .

  The raw material inlet 6 is a hole for introducing the raw material particles 16 into the particle reaction space 14, and is provided in a raw material particle supply jig 20 (raw material supply jig) as a raw material supply means in FIG. ing. The raw material inlet 6 is provided below the raw material container 21 so that the raw material particles 16 are supplied from the raw material container 21.

  More specifically, the raw material particle supply jig 20 is a ring-shaped member provided so as to cover the upper end surface of the rotary tube 3, and the raw material input port 6 has one end of the raw material particle supply jig 20. The other end is a through-hole provided so as to penetrate the side surface of the raw material particle supply jig 20 so as to penetrate the surface facing the particle reaction space 14 and communicate with the particle reaction space 14. . The raw material particles 16 are supplied into the particle reaction space 14 when the positions of the rotating raw material particle supply jig 20 and the holes of the fixed raw material inlet 6 coincide.

  However, the structure of the raw material supply means is not necessarily limited to the structure shown in FIG. 2, and the structures shown in FIGS. 6 and 7 are also possible.

  For example, in FIG. 6, the raw material inlet 6 is provided in the fixed pipe 2.

  Further, in FIG. 6, a through hole 51 is provided that penetrates from the particle reaction space 14 of the rotating tube 3 toward the side surface of the rotating tube 3 (the surface facing the fixed tube 2 of the rotating tube 3). The raw material supply port 6 and the through hole 51 constitute a raw material supply means.

  In this configuration, the raw material inlet 6 is formed so as to overlap (oppose) the through hole 51 at a predetermined rotation angle.

  Therefore, in the rotating rotating tube 3, when the through hole 51 and the raw material charging port 6 of the fixed tube 2 overlap, that is, when the through hole 51 and the raw material charging port 6 face each other, the raw material particles 16 are particles of the rotating tube 3. It is introduced into the reaction space 14.

  On the other hand, in the structure shown in FIG. 7, a C-shaped raw material particle supply jig 20a provided at the end (exposed portion) of the particle reaction space 14 constitutes a raw material supply means.

  More specifically, the raw material particle supply jig 20 a is provided around the end of the particle reaction space 14 on the upper end side of the rotary tube 3.

  Furthermore, the raw material particle supply jig 20a has a C-shape in which at least the side facing the outer periphery of the rotary tube 3 is cut out, and the raw material particles 16 are placed in the particle reaction space 14 in a C-shape. It is structured to be inserted intermittently from the missing part of the mold.

  The material constituting the raw material particle supply jigs 20 and 20a may be any material that can withstand the heating during operation of the apparatus and does not contaminate the raw material particles 16.

  An example of such a material is graphite when the raw material particles 16 contain carbon.

  The atmosphere gas supply port 27 and the exhaust port 24 are members that introduce and exhaust the atmosphere gas into the rotary furnace 1. However, the exhaust port 24 also exhausts the gas generated by the reaction of the raw material particles 16.

  The material of the atmosphere gas supply port 27 and the exhaust port 24 may be arbitrarily selected. For example, piping such as stainless steel or Cu can be used.

  The positions of the atmospheric gas supply port 27 and the exhaust port 24 are respectively provided below the lower end and above the upper end of the rotary tube 3 in FIG.

  However, the positions of the atmospheric gas supply port 27 and the exhaust port 24 are not necessarily limited to the positions shown in FIG. 1 because the installation positions are determined in consideration of the specific gravity of the gas generated by the heating reaction between the atmospheric gas and the raw material particles 16. It is not something.

  Further, the atmospheric gas supply port 27 may extend to the end of the rotary tube 3, or the outlet of the particle reaction space 14 (end on the product container 22 side) in order to cool the heat-treated reaction particles 17. You may provide in the position which supplies atmospheric gas to. Although the heater space gas supply hole 12 is also shown on the outlet side of the particle reaction space 14 in FIG. 2, it may be on the inlet side.

  The raw material container 21 is a member that temporarily stores the raw material particles 16 and supplies the raw material particles 16 into the rotary tube 3, and has a box shape (cylindrical shape) in which at least a part of the upper and lower ends is opened.

  A raw material quantitative supply mechanism 19 such as a screw feeder for controlling the supply amount of the raw material particles 16 is provided inside the raw material container 21.

  The above is the detailed description of each component of the rotary furnace 1.

  Next, the procedure of the heat treatment of the raw material particles 16 using the rotary furnace 1 will be described with reference to FIGS.

  First, raw material particles 16 are produced. Specifically, the raw materials are mixed at a predetermined ratio and formed into a predetermined size and shape in consideration of reactivity and the like. The raw material particles 16 are preferably formed, for example, by a granulating device using a known extrusion device or a press device, and then dried so that the raw material particles 16 can move without staying in the particle reaction space 14.

  The shape of the raw material particles 16 is not particularly limited. However, when the raw material particles 16 are spherical, it is preferable to avoid the spherical shape because the residence time in the rotary tube 3 cannot be secured.

  In addition, as a concrete shape of the raw material particle | grains 16, a cylindrical shape and a button shape are mentioned, for example.

  Next, atmospheric gas is introduced into the heater installation space 15 and the particle reaction space 14 from the atmospheric gas supply port 27 to replace the entire atmosphere in the furnace, and then the rotary tube 3 is rotated using the drive mechanism 37.

  It should be noted that the amount of the atmospheric gas introduced into the heater installation space 15 is such that the reaction gas generated when the raw material particles 16 react does not flow, that is, reacts with and exhausts other than the atmospheric gas into which the heater 29 is introduced. Since the amount is sufficient to prevent this, the amount may be smaller than the amount of the atmospheric gas introduced into the particle reaction space 14.

  On the contrary, when a large amount of atmospheric gas is supplied to the heater installation space 15, the atmospheric gas heated by the central heater 4 is exhausted by the atmospheric gas, which is not preferable.

  Next, using the power source 26, current is passed through the heater 29 through the electrode 25, and the heater 29 is heated by resistance.

  Since the heated heater 29 heats the inner wall of the heater installation space 15 of the rotary tube 3 by heat conduction and radiant heat through the atmospheric gas in the heater installation space 15, the heat generated from the heater 29 is generated in the rotary tube 3. And the inner wall of the particle reaction space 14 is heated.

  Next, the temperature of the rotary tube 3 is measured by the non-contact temperature measuring device 9.

  When this temperature reaches a predetermined temperature and stabilizes, the raw material particles 16 are introduced into the particle reaction space 14 from the raw material container 21 through the raw material inlet 6.

  The charged raw material particles 16 move along the tube wall by the rotation of the rotary tube 3 and move in the rotary tube 3 by the action of gravity due to the inclination of the rotary tube 3.

  At this time, the raw material particles 16 are heated by the inner wall of the particle reaction space 14 to cause a predetermined reaction according to the composition and the type of the atmospheric gas, and become the reaction particles 17.

  When the reaction particles 17 reach the lower end of the particle reaction space 14, the reaction particles 17 are collected in the product container 22.

  The atmosphere gas introduced into the heater installation space 15 and the particle reaction space 14 from the atmosphere gas supply port 27 is a reaction gas generated when the raw material particles 16 are heated, or a combination of the raw material particles 16 and the atmospheric gas. It is exhausted from the exhaust port 24 together with the reaction gas from the reaction.

  Here, as in the rotary furnace 1a according to the prior art shown in FIGS. 3 and 5, in the case where the raw material particles 16 are heated in the heater installation space 15a, that is, the heater installation space 15a and the particle reaction space. In the case of a structure in which 14a is shared by one space, the reaction gas generated by heating the raw material particles 16 and the reaction gas generated by the reaction between the raw material particles 16 and the atmospheric gas react with the central heater 4 and the rotary tube 3. , These may be consumed. At this time, the consumption of the central heater 4 which is higher in temperature and more likely to react is likely to be remarkable.

  When the central heater 4 is consumed, the heater diameter becomes narrower during continuous processing and deviates from a desired temperature distribution.

  Further, if the central heater 4 is further consumed, the central heater 4 may be broken.

  On the other hand, not only the central heater 4 but also the rotary tube 3 may be consumed due to the reaction, resulting in disconnection, and continuous heating may not be possible.

  However, in the rotary furnace 1, the heater installation space 15 and the particle reaction space 14 are separately provided in the rotary tube 3, and the raw material particles 16 are heated mainly by heat conduction from the rotary tube wall, The heater 29 has a structure that does not come into contact with the raw material particles 16 and the reactive particles 17, that is, the reactive gas generated when the raw material particles 16 are heated and the reactive gas generated by the reaction between the raw material particles 16 and the ambient gas.

  Therefore, the reaction gas generated by heating the raw material particles 16 or the reaction gas resulting from the reaction between the raw material particles 16 and the atmospheric gas does not react with the central heater 4 and be consumed.

  In the conventional rotary furnace 1a, the raw material particles 16 are directly heated mainly by radiant heat from the heater 29. In the rotary furnace 1, the raw material particles 16 are mainly supplied from the inner wall of the particle reaction space 14. It is heated by heat conduction.

  For this reason, it is possible to perform heating more gently than that directly heated by radiant heat as in the conventional rotary furnace 1a, to prevent local exhaustion of the rotary tube 3, and to make the quality of the reaction particles 17 uniform.

  Further, in the conventional rotary furnace 1a, the heated thermal energy is supplied to the inner wall of the rotary tube 3a that is hardly in contact with the raw material particles 16, and the heat is transferred to the fixed tube 2 and the heat insulating material 7 that are in contact with the rotary tube 3. In the rotary furnace 1, the heat energy heated by the central heater 4 is the space for particle reaction from the inner wall of the rotary tube 3, that is, the heater installation space 15, except for the heat energy generated by discharging the atmospheric gas. Since heat is stored in the member between the 14 inner walls, heat treatment can be performed more efficiently.

  Furthermore, in the case of the conventional rotary furnace 1a, if a large amount of the raw material particles 16 are supplied into the rotary tube 3 so as to increase the throughput per hour, the raw material particles 16 overflow from the inlet side due to the angle of repose of the raw material particles 16. It was inevitable.

  However, since the rotary furnace 1 has a plurality of particle reaction spaces 14, the rotary tube volume can be used effectively, and the supply amount of the raw material particles 16 per one particle reaction space 14 is small. The angle of repose is less likely to occur.

  Thus, according to the present embodiment, the rotary furnace 1 is provided with a heater provided in the rotary tube 3 so as to include the rotatable solid rotary tube 3 and the rotation center shaft 53 of the rotary tube 3. A resistance heating type heater 29 disposed in the heater installation space 15 so as to include the rotation space 15 and the rotation center shaft 53, and the heater installation space 15 along the rotation center shaft 53. A particle reaction space 14 into which the raw material particles 16 are charged is provided, and the raw material particles 16 are heated mainly by heat conduction from the inner wall of the particle reaction space 14.

  Therefore, the rotary furnace 1 has high thermal efficiency and can react the raw material particles 16 gently compared with the case where the radiant heat from the heater 29 is directly received.

  Further, according to the present embodiment, the heater installation space 15 and the particle reaction space 14 are provided separately.

  Therefore, the heater 29 is not in contact with the reaction gas generated by the heating of the raw material particles 16 or the reaction gas generated by the reaction between the raw material particles 16 and the ambient gas, so that the heater 29 is avoided from being consumed and is continuously operated with a long life. Is possible.

  Further, since the heater installation space 15 and the particle reaction space 14 are provided separately, the heater 29 is not locally consumed, and the temperature distribution in the furnace does not change depending on the processing time.

  Furthermore, according to the present embodiment, a plurality of particle reaction spaces 14 are equally arranged around the heater installation space 15.

  Therefore, compared with the rotary furnace 1a having a conventional structure in which the particle reaction space 14a and the heater installation space 15a are combined into one space, the heat treatment object is more frequently in contact with the heated particle reaction space 14 inner wall. Thus, uniform heating is possible, and it is possible to make uniform contact with the atmospheric gas.

  As mentioned above, although this invention was demonstrated based on embodiment, this invention is not limited to above-described embodiment.

  It is natural for those skilled in the art to come up with various modifications and improvements within the scope of the present invention, and it is understood that these also belong to the scope of the present invention.

  For example, in the above-described embodiment, the heater space gas supply hole 12 is provided in the heater 29 as a structure for introducing the atmospheric gas into the heater installation space 15, and the heater space gas supply nozzle 10 is provided via the insulator ring 11. Although the communication structure is adopted, the present invention is not limited to this.

  That is, as a structure for introducing the atmosphere gas, for example, a structure for introducing the atmosphere gas from the gap between the heater space atmosphere protection ring 13 at the entrance or exit of the rotary tube 3 and the central heater 4 without providing the heater space gas supply hole 12. Also good.

  Further, as a structure for introducing the atmosphere gas, the heater space atmosphere protection ring 13 may be fixed without rotating, and a hole may be formed in the heater space atmosphere protection ring 13 to introduce the atmosphere gas.

DESCRIPTION OF SYMBOLS 1 Rotating furnace 1a Rotating furnace 2 Fixed tube 3 Rotating tube 3a Rotating tube 4 Central heater 5 End heater 6 Raw material inlet 7 Heat insulating material 8 Temperature measuring port 9 Non-contact temperature measuring instrument 10 Heater space gas supply nozzle 11 Insulator ring 12 Heater space gas supply hole 13 Heater space atmosphere protection ring 14 Particle reaction space 14a Particle reaction space 15 Heater installation space 15a Heater installation space 16 Raw material particles 17 Reactive particles 18 Raw material particle input jig 19 Raw material quantitative supply mechanism 20 Raw material particle supply jig 20a Raw material particle supply jig 21 Raw material container 22 Product container 24 Exhaust port 25 Electrode 26 Power supply 27 Atmospheric gas supply port 28 Inclination angle adjustment mechanism 29 Heater 37 Drive mechanism 39 Motor 41 First gear 43 Second gear Gear 51 Through hole 53 Central axis of rotation 55 Horizontal plane

Claims (11)

A solid rotating body that can rotate,
A heating space provided inside the rotating body so as to include the rotation center axis of the rotating body;
A resistance heating type heater disposed in the heating space so as to include the rotation center axis;
A heat treatment space provided around the heating space so as to be along the rotation center axis and into which an object to be heat treated is charged,
A rotary furnace characterized by comprising:   The rotary furnace according to claim 1, wherein a plurality of the heat treatment spaces are uniformly arranged around the heating space. The rotating body is a cylinder;
The hollow portion of the cylinder constitutes the heating space,
The rotary furnace according to any one of claims 1 and 2, wherein the heat treatment space is formed in a thick portion of the cylinder.   The rotary furnace according to any one of claims 1 to 3, wherein the heating space and the heat treatment space are formed so as to penetrate the rotating body.   The rotary furnace according to claim 4, further comprising a ring provided at an end of the heating space and protecting an atmosphere inside the heating space. The heating space further includes supply means for supplying atmospheric gas to prevent the heater from being consumed,
The heater has a heater space gas supply port that communicates the heating space and the outside,
The rotary furnace according to claim 5, wherein the supply unit includes a heater space gas supply nozzle that supplies the atmosphere gas to the heating space through the heater space gas supply port.   The rotary furnace according to any one of claims 1 to 6, wherein a cross-sectional shape of the heat treatment space perpendicular to the rotation center axis is any one of a circle, a polygon, and a star.   The rotary furnace according to any one of claims 1 to 7, further comprising supply means for supplying the object to be heat treated to the heat treatment space. The supply means has a raw material supply jig provided on the rotating body,
The raw material supply jig has a through hole,
The rotary furnace according to claim 8, wherein one end of the through hole is communicated with the heat treatment space, and the other end forms a raw material inlet for supplying the material to be heat treated. A fixing portion provided around the rotating body and holding the rotating body;
The supply means includes a through hole provided through the heat treatment space from a surface facing the fixed portion of the rotating body;
A hole-shaped raw material inlet formed in the fixed portion so as to be opposed to the through hole;
Have
The rotary furnace according to claim 8, wherein when the through hole and the raw material charging port face each other by the rotation of the rotating body, the object to be heat treated is supplied to the heat treatment space.   The supply means has a C-shaped raw material supply jig provided around the exposed portion of the heat treatment space to the outside and having at least a side facing the outer periphery of the rotating body cut out. The rotary furnace according to claim 8.

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