Firing equipment

Abstract

To reduce electric consumption or fuel gas consumption in a continuous furnace.SOLUTION: An electric type calcination facility 100 including pusher type continuous furnaces comprises: a first continuous furnace 1 including a temperature rising zone, a holding zone, and a cooling zone; a second continuous furnace 2 including a temperature rising zone, a holding zone, and a cooling zone; a heat reserve bar 32; and actuation means 60, 70 for the heat reserve bar 32. The first and second continuous furnaces 1, 2 are adjacent to each other in a direction orthogonal to a furnace length direction, wherein transportation directions of a processed object are opposite to each other. The actuation means 60, 70 reciprocate the heat reserve bar 32 between a heat receiving position corresponding to one cooling zone out of the first and second continuous furnaces 1, 2 and a heat release position corresponding to the temperature rising zone of the other continuous furnace.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a firing facility provided with an electric or gas-fired continuous furnace.

Background Art

[0002] Electric or gas-fired continuous furnaces that continuously fire electronic components, ceramic molded bodies and the like are known. In this type of continuous furnace, a temperature raising zone, a holding zone and a cooling zone are arranged in this order from the upstream side to the downstream side in the conveying direction, a workpiece is heated and fired in the temperature raising zone and the holding zone, and the workpiece is cooled in the cooling zone.

Prior Art Literature

Patent Literature

[0003]

Patent Literature 1

Patent Literature 2

Summary of the Invention

Problem to be Solved by the Invention

[0004] The above-described continuous furnace has large electricity consumption or fuel gas consumption, and thus reduction thereof has been demanded. In a continuous furnace, as a means for cooling a processed workpiece after treatment, it is common to release thermal energy to the outside of the furnace through the cooling zone, but this means that part of the input energy is released, which is not preferable from the viewpoint of energy saving.

Means for Solving the Problem

[0005] The present inventors diligently studied the above problem and developed a continuous furnace that can effectively utilize the heat recovered in the cooling zone for the temperature raising treatment in the temperature raising zone.

[0006] The firing apparatus according to the present invention comprises (1) an electric or gas-fired continuous furnace, a first continuous furnace having a heating zone, a holding zone and a cooling zone, a second continuous furnace having a heating zone, a holding zone and a cooling zone, a heat storage rod, and an operating means for the heat storage rod, wherein the first and second continuous furnaces are adjacent to each other in a direction perpendicular to the furnace length direction, and the directions of conveying the processed material are opposite to each other, and the operating means reciprocates the heat storage rod between a heat receiving position corresponding to the cooling zone of one of the first and second continuous furnaces and a heat dissipation position corresponding to the heating zone of the other continuous furnace.

[0007] (2) The firing apparatus according to (1) above, characterized in that the operating means moves the heat storage rod to the heat dissipation position after waiting for a predetermined time at the heat receiving position, and moves the heat storage rod to the heat receiving position after waiting for a predetermined time at the heat dissipation position.

[0008] (3) The firing apparatus according to (1) or (2) above, characterized in that the temperature of the cooling zone at the heat receiving position is higher than the temperature of the heating zone at the heat dissipation position.

[0009] (4) The firing apparatus according to (1) above, characterized in that the number of heat storage rods is multiple.

[0010] (5) When the plurality of heat storage rods are grouped into a first heat storage rod group and a second heat storage rod group, the operating means moves the first heat storage rod group from one of the heat receiving position and the heat dissipation position to the other position, and moves the second heat storage rod group from the other position to the one position, as described in (4) above.

[0011] (6) The firing apparatus according to (5) above, characterized in that the operating means causes the first heat storage rod group to wait at one position for a predetermined time before moving it to the other position, and the second heat storage rod group to wait at the other position for a predetermined time before moving it to the one position.

[0012] (7) The firing apparatus according to (5) or (6) above, characterized in that the number of heat storage rods included in the first heat storage rod group and the number of heat storage rods included in the second heat storage rod group are the same.

[0013] (8) The firing apparatus according to any one of (5) to (7) above, characterized in that the heat storage rods included in the first heat storage rod group and the heat storage rods included in the second heat storage rod group are arranged alternately in the direction of conveying the workpiece.

[0014] (9) The firing apparatus according to any one of (4) to (8) above, characterized in that the temperature of the cooling zone at the heat receiving position is higher than the temperature of the heating zone at the heat dissipation position.

[0015] (10) The firing apparatus according to any one of (1) to (9) above, characterized in that the heat storage rod comprises a heat storage section and insulating sections provided at both ends of the heat storage section, the length of the heat storage rod is greater than the width of the furnace chamber, and the length of the heat storage section is less than the width of the furnace chamber.

[0016] (11) The firing apparatus according to any one of (1) to (10) above, characterized in that the heat receiving position is directly below the workpiece in the cooling zone of one of the continuous furnaces, and the heat dissipation position is directly below the workpiece in the heating zone of the other continuous furnace.

[0017] (12) The firing apparatus according to any one of (1) to (11) above, characterized in that the operating means is a cylinder. [Effects of the Invention]

[0018] According to the present invention, by moving a heat storage rod back and forth between the cooling zone and the heating zone of adjacent continuous furnaces, the heat recovered in the cooling zone can be utilized for heating in the heating zone. Since the heat that would have conventionally flowed out from the furnace wall of the cooling zone can be effectively utilized, electricity consumption or fuel gas consumption can be significantly reduced. [Brief explanation of the drawing]

[0019] [Figure 1] It is a schematic plan view of a firing facility. [Figure 2] It is an A1-A1' cross-sectional view of FIG. 1. [Figure 3] It is an A2-A2' cross-sectional view of FIG. 1. [Figure 4] It is an operation explanatory view of an actuating device that actuates a heat storage rod from a heat radiation position to a heat reception position. [Figure 5] It is an operation explanatory view of an actuating device that actuates a heat storage rod from a heat reception position to a heat radiation position. [Figure 6] It is a flow chart showing the operation procedure of a heat storage rod. [Figure 7] It is an arrangement diagram of heat storage rod groups arranged in a temperature rising zone and a cooling zone. [Figure 8] It is an arrangement diagram of the heat storage rod groups after moving the heat storage rod groups in FIG. 7. MODE FOR CARRYING OUT THE INVENTION

[0020] (First Embodiment) FIG. 1 is a schematic plan view of a firing facility. The firing facility 100 is an electric facility that heats and fires an object to be processed. The object to be processed may be a ceramic capacitor, a positive electrode material or a negative electrode material of a battery (for example, a lithium-ion battery), or the like. The firing facility 100 includes a first continuous furnace 1 and a second continuous furnace 2, and the first continuous furnace 1 and the second continuous furnace 2 are adjacent to each other in a direction orthogonal to the furnace length direction (hereinafter also referred to as an adjacent direction K). An arrow M1 indicates the conveyance direction of the object to be processed in the first continuous furnace 1, and an arrow M2 indicates the conveyance direction of the object to be processed in the second continuous furnace 2. The first continuous furnace 1 and the second continuous furnace 2 are installed such that the conveyance directions M1 and M2 are opposite to each other. In the present embodiment, the conveyance method for the object to be processed is a pusher type. However, the present invention is not limited to this.

[0021] In the first continuous furnace 1, a heating zone, a holding zone, and a cooling zone are provided in this order from the upstream side to the downstream side in the conveying direction M1. In the second continuous furnace 2, a heating zone, a holding zone, and a cooling zone are provided in this order from the upstream side to the downstream side in the conveying direction M2. The heating zone is the zone in which the furnace temperature is raised toward a predetermined temperature (in other words, the zone where heat is needed), and the cooling zone is the zone in which the processed material, which has been heated to a high temperature by the firing process, is cooled (in other words, the zone where heat is not needed). The temperature of the furnace is higher in the cooling zone than in the heating zone. The holding zone is the zone in which the temperature is maintained at a predetermined temperature. Furthermore, the first continuous furnace 1 and the second continuous furnace 2 are independent electric furnaces, and firing processes corresponding to the material being processed are carried out in each continuous furnace. Therefore, the furnace temperature, heating rate, cooling rate, furnace length, etc., of the first continuous furnace 1 and the second continuous furnace 2 are not necessarily the same.

[0022] The heating zone of the first continuous furnace 1 and the cooling zone of the second continuous furnace 2 are adjacent in the adjacent direction K.

[0023] Figure 2 is a cross-sectional view of Figure 1, taken from A1-A1', showing the firing equipment 100 cut at the point where the heating zone of the first continuous furnace 1 and the cooling zone of the second continuous furnace 2 are adjacent. Figure 3 is a cross-sectional view of Figure 1, taken from A2-A2', showing the firing equipment 100 cut at the point where the cooling zone of the first continuous furnace 1 and the heating zone of the second continuous furnace 2 are adjacent.

[0024] Referring to Figure 2, the first continuous furnace 1 includes a furnace wall 11 and a furnace chamber 12, and a heater 13 extending toward the furnace bottom is provided on the upper wall of the furnace chamber 12. The heater 13 is a heat resistance type heater that generates heat when an electric current is applied, and preferably a non-metallic silicon carbide heating element with excellent heat resistance and corrosion resistance can be used. However, the heater 13 is not limited to a silicon carbide heating element, and a Ni-Cr heating element, a molybdenum disilicide heating element, or a graphite heating element can also be used. By generating heat with the heater 13, the temperature of the material MF1 being transported in the furnace chamber 12 can be raised.

[0025] The second continuous furnace 2 includes a furnace wall section 21 and a furnace chamber section 22. Since Figure 2 shows a cross-sectional view of the second continuous furnace 2 in the cooling zone, the heater of the second continuous furnace 2 is not shown. Note that a heater may be installed upstream of the cooling zone to control the cooling rate. The upstream section of the cooling zone where such a heater is installed is also included in the "cooling zone" of the present invention (the same applies hereinafter). In the cooling zone of the second continuous furnace 2, the high-temperature processed material MF2 fired in the heating zone and holding zone of the second continuous furnace 2 is cooled. The cooling is not forced cooling using fans or the like, but rather natural cooling that allows heat to dissipate from the furnace wall 21 and the like.

[0026] A moving passage 31 is installed directly beneath the material MF1, which is heated in the first continuous furnace 1, and the material MF2, which is cooled in the second continuous furnace 2, and it traverses the first continuous furnace 1 and the second continuous furnace 2. This moving passage 31 is formed in a cylindrical shape (including, for example, a cylindrical or rectangular tube) and extends in the direction of the furnace width, penetrating the furnace wall 11, furnace chamber 12, furnace wall 21, and furnace chamber 22.

[0027] The heat storage rod 32 is housed in the moving passage 31. The heat storage rod 32 can be moved back and forth between a heat receiving position corresponding to the cooling zone of the second continuous furnace 2 and a heat dissipation position corresponding to the heating zone of the first continuous furnace 1. Figure 2 shows the heat storage rod 32 waiting at the heat receiving position of the second continuous furnace 2. By having the heat storage rod 32 wait at the heat receiving position of the second continuous furnace 2 for a predetermined time, the heat dissipated from the processed material MF2 can be stored in the heat storage rod 32. Also, by having the heat storage rod 32 wait at the heat dissipation position of the first continuous furnace 1 for a predetermined time, the heat stored in the heat storage rod 32 can be dissipated to the heating zone of the first continuous furnace 1.

[0028] The heat storage rod 32 consists of a heat storage section 32a and insulating sections 32b provided at both ends of the heat storage section 32a. It is desirable to use silicon carbide for the heat storage section 32a due to its superior properties in terms of contamination resistance, chemical stability, and cost. However, it is not limited to silicon carbide; other materials with high specific gravity and heat capacity (e.g., metal materials) may be used to construct the heat storage section 32a. For the insulating section 32b, a wide range of materials commonly used in insulating bricks can be used. For example, mullite and alumina-based materials can be suitably used. However, the insulating section 32b may be constructed from materials other than mullite and alumina-based materials.

[0029] Here, it is desirable to make the length of the heat storage rod 32 greater than the width of the furnace chamber, and the length of the heat storage section 32a less than the width of the furnace chamber. With this configuration, it is possible to suppress the outflow of heat stored in the heat storage rod 32 from the furnace wall section 21. In other words, if the entire heat storage rod 32 is made of heat storage material, heat will easily escape from the heat storage material extending into the furnace wall section 21 through the furnace wall section 21. By limiting the installation range of the heat storage section 32a to the furnace chamber, avoiding the furnace wall section 21, and by making both ends of the heat storage section 32a insulating material, the heat storage effect of the heat storage rod 32 can be enhanced. The heat storage rod 32 may also be composed solely of the heat storage section 32a. In this case, it is desirable that the length of the heat storage rod 32 be shorter than the width of the furnace chamber.

[0030] Referring to Figure 3, a heater 23 extending toward the bottom of the furnace is provided on the upper wall of the furnace chamber 22 of the second continuous furnace 2. Figure 3 shows a heat storage rod 42 waiting at the heat receiving position of the first continuous furnace 1. By having the heat storage rod 42 wait at the heat receiving position of the first continuous furnace 1 for a predetermined time, the heat released from the material MF1 can be stored in the heat storage rod 42. Also, by having the heat storage rod 42 wait at the heat dissipation position of the second continuous furnace 2 for a predetermined time, the heat stored in the heat storage rod 42 can be released into the heating zone of the second continuous furnace 2. Note that the first continuous furnace 1 shown in Figure 3 is a cross-sectional view of the cooling zone, so the heater of the first continuous furnace 1 is not shown. The moving passage 41 and the heat storage rod 42 are the same as the moving passage 31 and the heat storage rod 32, respectively, so a detailed explanation is omitted.

[0031] The operating mechanism for the heat storage rod will be explained with reference to Figures 4 and 5. Figure 4 corresponds to Figure 2 and shows the state immediately after the heat storage rod 32 arrives at the heat receiving position of the second continuous furnace 2. Figure 5 corresponds to Figure 2 and shows the state immediately after the heat storage rod 32 arrives at the heat dissipation position of the first continuous furnace 1.

[0032] A first actuator 60 is installed on the side of the first continuous furnace 1, and a second actuator 70 is installed on the side of the second continuous furnace 2. The first actuator 60 is a hydraulic cylinder and is equipped with a piston rod 61. The piston rod 61 is positioned in a location corresponding to the movement passage 31. Therefore, by extending the piston rod 61, the heat storage rod 32 can be pushed from the heat dissipation position of the first continuous furnace 1 toward the heat receiving position of the second continuous furnace 2 (see Figure 4).

[0033] The configuration of the second actuator 70 may be the same as that of the first actuator 60. By extending the piston rod 71 of the second actuator 70, the heat storage rod 32 can be pushed from the heat receiving position of the second continuous furnace 2 toward the heat dissipation position of the first continuous furnace 1 (see Figure 5).

[0034] In this embodiment, the first actuator 60 and the second actuator 70 are configured as hydraulic cylinders, but the present invention is not limited thereto, and other actuators different from hydraulic cylinders may be used. These other actuators may be air cylinders or electric cylinders. A similar actuator is also located at the position shown in the cross-sectional view of Figure 3, but we will not repeat the explanation.

[0035] Next, the operation procedure of the heat storage rod will be explained with reference to the flowchart in Figure 6. In the initial state, the heat storage rod 32 is positioned at the heat receiving position of the second continuous furnace 2 (see Figure 4). This flowchart can be executed by the control device that controls the operation of the first actuator 60 and the second actuator 70. The control device can utilize general computer equipment such as computing units like CPUs (Central Processing Units) and GPUs (Graphics Processing Units), main memory devices like RAM (Random Access Memory), auxiliary storage devices like HDDs (Hard Disk Drives), SSDs (Solid State Drives), and flash memory, and server devices.

[0036] In step S101, the elapsed time (hereinafter also referred to as the heat reception time) since the heat storage rod 32 reached the heat receiving position (see Figure 4) of the second continuous furnace 2 is counted. The processed material MF2 that has reached the cooling zone is releasing a large amount of heat. Conventionally, the heat released from the processed material MF2 flowed out through the furnace wall 21 and was not effectively utilized. In this embodiment, by having the heat storage rod 32 wait at the heat receiving position, the heat released from the processed material MF2 can be stored in the heat storage rod 32. The longer the heat reception time, the greater the amount of heat stored in the heat storage rod 32.

[0037] In step S102, it is determined whether the heat reception time has reached a predetermined time. If the heat reception time is too short, the heat storage rod 32 will not store enough heat, and the heating effect at the heat dissipation position will decrease. If the predetermined time is too long, the heat storage rod 32 will not absorb enough heat, and heat will escape. Therefore, it is desirable to set the predetermined time appropriately, taking into account the heat capacity of the heat storage rod 32, the amount of heat dissipated by the processed material MF2, etc. For this reason, in the embodiment described later, 520 seconds was set as the predetermined time (waiting time), but the present invention is not limited to this.

[0038] When the heat reception time reaches a predetermined time (step S102 Yes), in step S103, the second actuator 70 is activated to extend the piston rod 71 toward the movement passage 31. As the piston rod 71 extends further, the tip of the piston rod 71 comes into contact with the end of the heat storage rod 32, allowing the heat storage rod 32 to move from the heat reception position (see Figure 4) toward the heat dissipation position (see Figure 5).

[0039] In step S104, it is determined whether or not the heat storage rod 32 has reached the heat dissipation position. If the stroke amount of the piston rod 71 from the heat receiving position to the heat dissipation position of the heat storage rod 32 is determined in advance, the above determination process can be performed by monitoring the stroke amount of the piston rod 71. However, the determination method is not limited to this. For example, a reed switch, which is commonly used for detecting cylinder position, may be used.

[0040] In step S105, the elapsed time (hereinafter also referred to as heat release time) since the heat storage rod 32 reached the heat release position (see Figure 5) of the first continuous furnace 1 is counted. By having the heat storage rod 32 wait at the heat release position, the processed material MF1 located in the heating zone can be heated. In other words, some of the heat that would conventionally flow out from the furnace wall 21 can be stored in the heat storage rod 32 and effectively utilized for heating the processed material MF1. As the heat release time increases, the amount of heat stored in the heat storage rod 32 decreases.

[0041] In step S106, it is determined whether the heat dissipation time has reached a predetermined time. The predetermined time may be the same as the heat reception time in step S102. If the heat dissipation time has reached the predetermined time (step S106 Yes), in step S107, the first actuator 60 is activated to extend the piston rod 61 toward the movement passage 31. When the piston rod 61 is further extended, the tip of the piston rod 61 comes into contact with the end of the heat storage rod 32, and the heat storage rod 32 can be moved from the heat dissipation position (see Figure 5) toward the heat reception position (see Figure 4).

[0042] In step S108, it is determined whether the piston rod 61 has reached the heat receiving position. The method for determining this was explained in step S104, so it will not be repeated here. If the piston rod 61 has reached the heat receiving position, it is shortened and moved out of the movement passage 31. If the piston rod 61 has reached the heat receiving position (step S108 Yes), the process returns to step S101.

[0043] As explained above, by moving the heat storage rod 32 back and forth between the heat receiving position and the heat dissipation position, the heat recovered at the heat receiving position can be effectively utilized as energy for raising the temperature of the material MF1. Furthermore, since the heating and cooling processes are accelerated by the heat storage rod 32, the productivity of the firing equipment 100 is improved, and the cooling zones of the first continuous furnace 1 and the second continuous furnace 2 can be shortened. In addition, since the heating process is accelerated by the heat storage rod 32, the amount of electricity supplied to the heater 13 in the heating zone can be reduced. Moreover, in the case of a gas-combustion type continuous furnace, the amount of fuel gas used to heat the heating zone can be reduced.

[0044] Even at the position corresponding to Figure 3 (A2-A2' cross-section in Figure 1), a similar effect can be obtained by moving the heat storage rod 42 back and forth between the heat receiving position corresponding to the cooling zone of the first continuous furnace 1 and the heat dissipation position corresponding to the heating zone of the second continuous furnace 2.

[0045] Here, the waiting time at the heat receiving position (heat dissipation position) of the heat storage rod 32 and the waiting time at the heat receiving position (heat dissipation position) of the heat storage rod 42 may be the same or different. For example, if the materials to be processed in the first continuous furnace 1 and the second continuous furnace 2 are different, the firing process may be carried out with a temperature pattern suitable for each material. In this case, the waiting time at the heat receiving position (heat dissipation position) of the heat storage rod 32 and the waiting time at the heat receiving position (heat dissipation position) of the heat storage rod 42 may be different.

[0046] In this embodiment, heat storage rods are installed at two locations, A1-A1' and A2-A2', in Figure 1, but one of them may be omitted. Furthermore, heat storage rods may be installed at three or more locations.

[0047] In the above-described embodiment, the continuous furnace was of the heating type, but the present invention can also be applied to a gas-combustion type continuous furnace (the same applies to the second embodiment). That is, the above-described effects can also be obtained by arranging gas-combustion type continuous furnaces adjacent to each other and moving the heat storage rod 32 back and forth between the heat receiving position and the heat dissipation position. The operation method of the heat storage rod 32 is the same as that of the heating type continuous furnace, so a detailed explanation will be omitted.

[0048] (Second Embodiment) In the first embodiment, a single heat storage rod was moved back and forth between the heat dissipation position (heat receiving position) of the first continuous furnace 1 and the heat receiving position (heat dissipation position) of the second continuous furnace 2. In this embodiment, however, multiple heat storage rods are moved back and forth. Figures 7 and 8 are plan views of a portion of the heating zone of the first continuous furnace 1 and a portion of the cooling zone of the second continuous furnace 2. Note that, in order to simplify the drawings, the operating device is omitted from the illustrations.

[0049] The first moving passage 311, the second moving passage 312, the third moving passage 313, and the fourth moving passage 314 are each cylindrical (including, for example, cylindrical, rectangular, etc.) moving passages that traverse the heating zone of the first continuous furnace 1 and the cooling zone of the second continuous furnace 2, and correspond to the moving passage 31 of the first embodiment. In the transport direction M2, the first moving passage 311 is located adjacent to the upstream of the third moving passage 313, the third moving passage 313 is located upstream of the second moving passage 312 at a predetermined distance, and the second moving passage 312 is located adjacent to the upstream of the fourth moving passage 314.

[0050] The first, second, third, and fourth moving passages 311, 312, 313, and 314 respectively house the first, second, third, and fourth heat storage rods 321, 322, 323, and 324 heat storage rods. In other words, in the transport direction M2, the first, third, second, and fourth heat storage rods 321, 323, 322, and 324 heat storage rods are arranged in this order.

[0051] For the sake of explanation, these heat storage rods are grouped into a first heat storage rod group G1 consisting of the first heat storage rod 321 and the second heat storage rod 322, and a second heat storage rod group G2 consisting of the third heat storage rod 323 and the fourth heat storage rod 324.

[0052] The operation of the first heat storage rod group G1 and the second heat storage rod group G2 is synchronized. When the first heat storage rod group G1 moves from the heat receiving position in the cooling zone to the heat dissipation position in the heating zone, the second heat storage rod group G2 moves from the heat dissipation position in the heating zone to the heat receiving position in the cooling zone. The point that the heat storage rods are made to wait for a predetermined time at the heat dissipation position and the heat receiving position is the same as in the first embodiment, so a detailed explanation is omitted.

[0053] Therefore, as shown in Figures 7 and 8, the heat storage rods included in the first heat storage rod group G1 and the heat storage rods included in the second heat storage rod group G2 are arranged alternately in the transport direction M2. In other words, in Figure 7, the first heat storage rod 321 (heat receiving position in the cooling zone), the third heat storage rod 323 (heat dissipation position in the heating zone), the second heat storage rod 322 (heat receiving position in the cooling zone), and the fourth heat storage rod 324 (heat dissipation position in the heating zone) are arranged in this order toward the transport direction M2. Also, in Figure 8, the first heat storage rod 321 (heat dissipation position in the heating zone), the third heat storage rod 323 (heat receiving position in the cooling zone), the second heat storage rod 322 (heat dissipation position in the heating zone), and the fourth heat storage rod 324 (heat receiving position in the cooling zone) are arranged in this order toward the transport direction M2.

[0054] Therefore, in the transport direction M2, the continuous furnace can be operated with the heat storage rods located at the heat receiving position and the heat storage rods located at the heat dissipation position arranged alternately (excluding the time the heat storage rods move), in other words, with the heat storage rods evenly distributed.

[0055] Furthermore, in this embodiment, the number of heat storage rods placed at the heat receiving position in the cooling zone and the number of heat storage rods placed at the heat dissipation position in the heating zone are the same (in other words, the number of heat storage rods included in heat storage rod groups G1 and G2 are the same), thus eliminating any imbalance in the heat storage rods in the first continuous furnace 1 and the second continuous furnace 2. Therefore, an even number is desirable for the total number of heat storage rods. If the total number of heat storage rods is even, the number of heat storage rods placed at the heat receiving position in the cooling zone and the number of heat storage rods placed at the heat dissipation position in the heating zone can be made the same. However, the total number of heat storage rods is not limited to an even number; it may also be an odd number.

[0056] The configuration of the first to fourth heat storage rods 321 to 324 is the same as that of the heat storage rod 32 in the first embodiment, so a detailed explanation is omitted. Also, the means for moving the first to fourth heat storage rods 321 to 324 is the same as that of the operating device in the first embodiment, so a detailed explanation is omitted. The method for moving the heat storage rod is the same as in the first embodiment, which will be explained with reference to the flowchart in Figure 6, so a detailed explanation will be omitted.

[0057] The heat storage rod groups G1 and G2 described above can be installed in positions where the heating zone (cooling zone) of the first continuous furnace 1 and the cooling zone (heating zone) of the second continuous furnace 2 are adjacent to each other. There may be one installation location or multiple installation locations.

[0058] (Examples) The present invention will be specifically described with reference to examples. The energy input to the continuous furnace and the energy recovered by the heat storage rods were determined by simulation, and the energy reduction effect was evaluated. The study focused on electric continuous furnaces (pusher type, resistance heating type). The arrangement and operation method of the heat storage rods followed the second embodiment, which is explained with reference to Figure 7. The specifications of the heat storage rods were as follows: the heat storage section used a cylindrical silica carbide material with an outer diameter of 100 mm and a total length of 1200 mm; an insulating section made of alumina material with an outer diameter of 100 mm and a total length of 350 mm was placed at one end of the heat storage section; and an insulating section made of alumina material with an outer diameter of 100 mm and a total length of 280 mm was placed at the other end. The waiting time for the heat storage rods at both the heat receiving and heat dissipation positions was uniformly set to 520 seconds. This calculation was based on the assumption that the continuous furnace was operating stably.

[0059] The input energy was defined as the sum of (1) the amount of heat required to raise the material to a predetermined set temperature, (2) the amount of heat required to raise the temperature of the tools to a predetermined set temperature, (3) the amount of heat required to raise the temperature of the input gas to the set temperature inside the furnace, (4) the amount of latent heat of vaporization related to the water vapor contained in the material and tools, and (5) the amount of heat leaking from the outside of the furnace body to the outside space through the furnace walls and furnace body. Each heat quantity was calculated by referring to the furnace temperature at the inlet and outlet of the heating zone and holding zone, the temperature of the material at the inlet and outlet of the heating zone and holding zone, the processing weight per unit time of the material, tools, and furnace gas, and the specific heat capacity of each component (material, tools, input gas, and furnace structural material).

[0060] The heat output of (1) was 53.3 kW, the heat output of (2) was 154.7 kW, the heat output of (3) was 77.4 kW, the heat output of (4) was 55.0 kW, and the heat output of (5) was 83.8 kW. Therefore, the total energy input was 424.1 kW.

[0061] The recovered energy is the thermal energy (radiant heat) that moves from the cooling zone of one continuous furnace to the heating zone of the other continuous furnace via the heat storage rods. Therefore, the recovered energy for each heat storage rod was derived from the Stefan-Boltzmann law, and its sum was defined as the "recovered energy." The recovered energy (total value) was 46.7 kW. Therefore, we were able to recover (reuse) 11.0% of the input energy. [Explanation of Symbols]

[0062] 100 Firing equipment 1. First continuous reactor 2. Second continuous furnace 11 21 Furnace wall 12 22 Furnace chamber 13 23 Heater 31 41 311~314 Access Passage 32 42 321~324 Heat storage rod 32a Heat storage part 32b Insulation section 60 First actuator 70 Second actuator

Claims

1. In a firing facility equipped with an electric or gas-fired continuous furnace, A first continuous furnace equipped with a heating zone, a holding zone and a cooling zone, A second continuous furnace equipped with a heating zone, a holding zone and a cooling zone, A heat storage rod, The operating means for the heat storage rod, It has, The first and second continuous furnaces are adjacent to each other in a direction perpendicular to the furnace length direction, and the directions in which the material is transported are opposite to each other. The operating means reciprocates the heat storage rod between a heat receiving position corresponding to the cooling zone of one of the first and second continuous furnaces and a heat dissipation position corresponding to the heating zone of the other continuous furnace. A firing apparatus characterized by the following features.

2. The aforementioned operating means is After the heat storage rod is left at the heat receiving position for a predetermined time, it is moved to the heat dissipation position. After the heat storage rod is left at the heat dissipation position for a predetermined time, it is moved to the heat receiving position. The firing apparatus according to feature 1.

3. The firing apparatus according to claim 1 or 2, characterized in that the temperature of the cooling zone at the heat receiving position is higher than the temperature of the heating zone at the heat dissipation position.

4. The firing apparatus according to claim 1, characterized in that the number of heat storage rods is multiple.

5. When the aforementioned plurality of heat storage rods are grouped into a first heat storage rod group and a second heat storage rod group, The aforementioned operating means is When moving the first heat storage rod group from one of the heat receiving position and the heat dissipation position to the other position, the second heat storage rod group is moved from the other position to the one position. The firing apparatus according to feature 4.

6. The aforementioned operating means is The first group of heat storage rods is left waiting at one of the positions for a predetermined time, and then moved to the other position. The second group of heat storage rods is left to wait at the other position for a predetermined time, and then moved to the other position. The firing apparatus according to feature 5.

7. The number of heat storage rods included in the first heat storage rod group is the same as the number of heat storage rods included in the second heat storage rod group. The firing apparatus according to claim 5 or 6, characterized by the above.

8. The firing apparatus according to claim 5 or 6, characterized in that the heat storage rods included in the first heat storage rod group and the heat storage rods included in the second heat storage rod group are arranged alternately in the direction of conveying the processed material.

9. The firing apparatus according to any one of 4 to 6, characterized in that the temperature of the cooling zone at the heat receiving position is higher than the temperature of the heating zone at the heat dissipation position.

10. The heat storage rod consists of a heat storage section and heat insulating sections provided at both ends of the heat storage section. The length of the heat storage rod is greater than the width of the furnace chamber. The length of the heat storage section is smaller than the width of the furnace chamber. The firing apparatus according to claim 1 or 2.

11. The heat storage rod consists of a heat storage section and heat insulating sections provided at both ends of the heat storage section. The length of the heat storage rod is greater than the width of the furnace chamber. The length of the heat storage section is smaller than the width of the furnace chamber. The firing apparatus according to claim 3.

12. The heat storage rod consists of a heat storage section and heat insulating sections provided at both ends of the heat storage section. The length of the heat storage rod is greater than the width of the furnace chamber. The length of the heat storage section is smaller than the width of the furnace chamber. A firing apparatus according to any one of the features described in 4 to 6.

13. The heat storage rod consists of a heat storage section and heat insulating sections provided at both ends of the heat storage section. The length of the heat storage rod is greater than the width of the furnace chamber. The length of the heat storage section is smaller than the width of the furnace chamber. The firing apparatus according to feature 7.

14. The heat storage rod consists of a heat storage section and heat insulating sections provided at both ends of the heat storage section. The length of the heat storage rod is greater than the width of the furnace chamber. The length of the heat storage section is smaller than the width of the furnace chamber. The firing apparatus according to feature 8.

15. The heat storage rod consists of a heat storage section and heat insulating sections provided at both ends of the heat storage section. The length of the heat storage rod is greater than the width of the furnace chamber. The length of the heat storage section is smaller than the width of the furnace chamber. The firing apparatus according to feature 9.

16. The heat receiving position is directly below the workpiece in the cooling zone of the one continuous furnace. The heat dissipation position is directly below the workpiece in the heating zone of the other continuous furnace. The firing apparatus according to feature 1 or 4.

17. The aforementioned operating means is a cylinder. The firing apparatus according to feature 1 or 4.

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