JP5002765B2 - Processing method - Google Patents

Description

The present invention also relates to the processing how.

  As a method for producing reduced iron, a treatment method is known in which an iron compound containing iron oxide is placed in a treatment furnace and heated in a reducing atmosphere containing hydrogen or the like to reduce the oxide (Patent Document 1, Patent Document 1). 2).

JP-A-11-106811 JP 2004-225104 A

  Since the reduction reaction performed in the processing furnace is an endothermic reaction and the temperature is lowered, the processing furnace needs to be actively heated. However, in the conventional processing method, it is difficult to improve the heating efficiency of the processing furnace. In addition, the load of heating means such as an electric heater used to heat the processing furnace is large, and there is a problem that the cost required for heating such as an electricity bill is high. In particular, immediately after the start of the reduction reaction, the temperature in the processing furnace has decreased significantly, and it took a long time to raise the temperature in the processing furnace to a predetermined value. As a result, the processing efficiency could not be improved.

The present invention has been made in view of the above, even if the endothermic reaction, and to provide a processing method that can efficiently heat the inside of the processing furnace.

In order to solve the above problems , according to the present invention, there is provided a processing method for processing an object to be processed by an endothermic reaction, wherein the heated processing gas is introduced into the processing furnace before the object to be processed is put into the processing furnace. While exhausting, the inside of the processing furnace is exhausted, the heat of the exhaust gas exhausted from the inside of the processing furnace is stored in a regenerator, and then the object to be processed is put into the processing furnace, and the endothermic reaction treatment of the object to be processed is performed. When the endothermic reaction treatment is performed, the exhaust gas exhausted from the inside of the processing furnace is passed through the regenerator, the temperature is increased by the heat storage, and the exhaust gas heated by the heat storage and the inside of the processing furnace are A processing method is provided in which the processing gas is heated and supplied into the processing furnace by performing heat exchange with the processing gas supplied to the processing furnace.

  In this processing method, the processing gas heated by the heat exchange may be further heated by a heater and then supplied into the processing furnace. Further, the exhaust gas may be supplied to the processing furnace as a processing gas. The object to be treated may contain an oxide, the treatment gas may contain hydrogen, and the endothermic reaction may be a reduction reaction that reduces the oxide.

  According to the present invention, before the processing of the object to be processed is started, the heated processing gas is supplied into the processing furnace, and the exhaust gas discharged from the processing furnace is introduced into the regenerator so that the heat of the exhaust gas is reduced. Heat can be stored. After the processing of the object to be processed is started, the processing gas before being supplied to the processing furnace can be heated using the heat stored in the heat accumulator and then supplied to the processing furnace. Therefore, even if an endothermic reaction occurs, the inside of the processing furnace can be efficiently heated and the load on the heater can be reduced.

Hereinafter, a preferred embodiment of the present invention will be described based on a processing apparatus that performs a reduction process on an object to be processed. As shown in FIG. 1, the processing apparatus 1 according to the present embodiment contains hydrogen (H ₂ ) or the like in a processing furnace 2 having a processing chamber into which an object to be processed is charged and in the processing furnace 2 (processing chamber). A supply path 3 for supplying a reducing process gas, and a discharge path 4 for discharging the treated process gas and the like from the process furnace 2 as exhaust gas are provided. The object to be processed is reduced iron powder containing iron oxide (FeO) as an oxide.

  In the supply path 3, an electric heater 11 that is a heating means for heating the atmosphere in the heat exchanger 10 and the processing furnace 2 is provided in this order from the upstream side toward the processing furnace 2 side. A heat accumulator 15 and a heat exchanger 10 for accumulating the heat of the exhaust gas are interposed in the discharge path 4 in this order from the processing furnace 2 side to the downstream side. The upstream end of the supply path 3 and the downstream end of the discharge path 4 are connected to a blower 18. In such a configuration, the exhaust gas discharged from the inside of the processing furnace 2 through the discharge path 4 is introduced into the supply path 3 by the operation of the blower 18 and is again supplied as processing gas into the processing furnace 2. That is, a circulation line 20 for circulating the processing gas in the order of the supply path 3, the processing furnace 2, and the discharge path 4 is configured. Further, in the discharge path 4, an introduction path 23 connected to a supply source 22 that supplies unused processing gas is interposed between the heat exchanger 10 and the blower 18. The introduction path 23 is connected to the discharge path 4 via a switching on / off valve 25. By the operation of the switching on-off valve 25, the processing gas is introduced from the introduction path 23 into the supply path 3 via the blower 18, and the processing gas is introduced from the discharge path 4 into the supply path 3 via the blower 18. The state can be switched.

  In the heat exchanger 10, a processing gas on the way from the blower 18 to the processing furnace 2 is introduced in the supply path 3, and an exhaust gas on the way from the heat accumulator 15 to the blower 18 is introduced in the discharge path 4. That is, the exhaust gas heated by the heat storage of the heat accumulator 15 is supplied to the heat exchanger 10 provided on the downstream side of the heat accumulator 15 in the discharge path 4 and supplied to the processing furnace 2 from the exhaust gas and the supply path 3. By performing heat exchange with the previous process gas in a non-contact state, the process gas is heated. The processing gas preheated in the heat exchanger 10 using the heat storage of the heat accumulator 15 in this way is further raised to a predetermined temperature by the heater 11 provided on the downstream side of the heat exchanger 10 in the supply path 3. After being heated, it is supplied to the processing furnace 2. Thus, the heated processing gas causes the heat storage of the heat accumulator 15 and the heat of the heater 11 to be carried into the processing furnace 2 so that the processing furnace 2 is heated.

  As shown in FIG. 2, the heat accumulator 15 includes a casing 30 into which exhaust gas as a fluid is introduced, an inlet 31 for introducing exhaust gas into the casing 30, and an outlet 32 for deriving exhaust gas from the casing 30. ing. Inside the casing 30 is provided a heat storage body 33 that contacts the exhaust gas and stores heat.

  The casing 30 includes a cylindrical portion 30a having a substantially rectangular tube shape having four flat side walls, and further includes a ceiling portion 30b and a cylindrical portion 30a that closes an upper portion of a space surrounded by the cylindrical portion 30a. The bottom part 30c which obstruct | occludes the lower part of the enclosed space is provided. The bottom portion 30c is composed of four flat bottom plates provided inward from the lower portions of the side walls constituting the cylindrical portion 30a, and each bottom plate gradually moves downward as it goes inward from the side walls. So that it is tilted. Therefore, the bottom 30c is formed in a substantially quadrangular pyramid shape that is narrowed from the top to the bottom. Further, as shown in FIG. 3, support columns 35 as casing support members for supporting the casing 30 with respect to an external mounting table, a floor surface or the like are provided at a plurality of locations, for example, 8 locations, on the peripheral surface of the bottom surface of the bottom portion 30c. It is attached.

  The casing 30 is formed by joining two or more metal plates by welding or the like. As shown in FIG. 4, the casing 30 is provided between the side wall of the cylindrical portion 30a and the bottom plate of the bottom portion 30c connected to the side wall. Each of the corner portions 37 is preferably formed by bending a metal plate, and the corner portion 37 preferably has no joint between the metal plates by welding or the like. If it does so, the intensity | strength of the corner | angular part 37 can be ensured and it can prevent that damage, such as a crack and a fracture | rupture, occurs in the corner | angular part 37. For example, when the cylindrical portion 30a and the bottom portion 30c are joined together by welding at the corner portion 37, when the inside of the casing 30 is heated, the metal plate of the cylindrical portion 30a tends to expand downward due to thermal expansion. The metal plate of the bottom portion 30c tends to extend obliquely upward toward the cylindrical portion 30a side. For this reason, stress concentrates on the corner portion 37 and a crack may occur. On the other hand, when the corner portion 37 has no seam, durability when the cylindrical portion 30a and the bottom portion 30c are thermally expanded can be increased.

  In the illustrated example, the upper part of the bottom part 30c and the lower part of the cylindrical part 30a are integrally formed by bending and deforming a single continuous metal plate 41, and the cylindrical part 30a is made of metal. The plate 41 is constituted by a flat plate-like portion above the bent portion and another metal plate 42. The lower edge of the metal plate 42 is joined to the upper edge of the metal plate 41 by welding. The joint 43 between the metal plates 41 and 42 is disposed along substantially the same height as the upper surface of the holding plate 52 described later.

  An inner heat insulating material 45 and an outer heat insulating material 46 having heat insulation properties are respectively provided on the inner surface and the outer surface of the casing 30. The internal heat insulating material 45 is provided in layers having a predetermined thickness so as to cover the entire inner surface of the cylindrical portion 30a, the ceiling portion 30b, and the bottom portion 30c. The external heat insulating material 46 is provided in a layer shape having a predetermined thickness so as to cover the entire outer surface of the cylindrical portion 30a, the ceiling portion 30b, and the bottom portion 30c. As a material of the internal heat insulating material 45, for example, ceramic fiber (manufactured by NICHIAS Corporation, trade name: Fine Flex) may be used. As the material of the external heat insulating material 46, for example, glass wool or the like may be used. By providing the internal heat insulating material 45 in this way, the heat resistance of the casing 30 and the heat insulating property in the casing 30 can be improved. Further, by providing the external heat retaining material 46, the heat retaining property in the casing 30 can be further improved.

  As shown in FIG. 2, the introduction port 31 is opened at the center of the ceiling portion 30 b above the heat storage body 33. Connected to the inlet 31 is an upstream discharge path 4 a for sending exhaust gas from the processing furnace 2 side to the heat accumulator 15. Below the introduction port 31, a dispersion plate 47 is provided between the introduction port 31 and the heat storage body 33 to disperse the exhaust gas introduced from the introduction port 31 from below the introduction port 31 to the outside toward the cylindrical portion 30a. It has been.

  The lead-out port 32 is opened at the center lower end portion of the bottom portion 30c below the heat storage body 33 and a heat storage body holding body 51 described later. Connected to the outlet 32 is a downstream discharge path 4 b for sending exhaust gas from the regenerator 15 to the heat exchanger 10.

  The heat storage body 33 is configured by a thin plate-shaped heat storage material 50 having a plurality of substantially square shapes. Each of the heat storage materials 50 is erected in a substantially parallel posture in the substantially vertical direction (vertical direction), and between the adjacent heat storage materials 50 in the substantially horizontal direction (lateral direction). Are arranged side by side with a predetermined interval.

  The heat storage body 33 is held by a heat storage body holding body 51 provided on the bottom 30 c in the casing 30. The heat storage body holding body 51 includes a substantially lattice-shaped holding plate 52 on which the heat storage body 33 is placed and a mount 53 on which the holding plate 52 is placed.

  As shown in FIG. 5, the holding plate 52 has a lattice shape constituted by a plurality of elongated vertical plates 52a and horizontal plates 52b, and a plurality of substantially square shapes surrounded by the vertical plates 52a and the horizontal plates 52b. A communication opening 52c provided through the holding plate 52 in the vertical direction is provided. The vertical plates 52a are extended at a predetermined height with the length direction turned sideways, and are arranged in parallel with each other at a predetermined interval. The horizontal plates 52b are extended in a predetermined height at a predetermined height so as to cross each vertical plate 52a substantially vertically, and are substantially parallel to each other with a predetermined interval. It is provided side by side. Each heat storage material 50 is directed, for example, in a direction substantially parallel to the vertical plate 52a, and is placed on and held on the upper surface of the holding plate 52 so that the lower side is in contact with the upper edges of the plurality of horizontal plates 52b. ing. The exhaust gas introduced from the introduction port 31 descends through the gaps between the respective heat storage materials 50 of the heat storage body 33, flows out below the holding plate 52 through the respective communication ports 52 c, and is led out by the outlet port 32. It has come to be. In addition, as a material of the holding plate 52, it is preferable to use a material having rigidity and heat resistance. For example, a steel material such as SUS304 may be used.

  As shown in FIG. 6, the gantry 53 is provided between the frame member 61 formed in a substantially rectangular frame shape along each side wall of the cylindrical portion 30a, and the lower surface of the frame member 61 and the bottom portion 30c. And a plurality of frame support members 62. The frame member 61 is supported by a frame support member 62 and is attached to the casing 30 via the frame support member 62. A plurality of heat insulating materials 63 are provided on the upper surface of the frame member 61.

  As shown in FIG. 4, the frame member 61 includes a bottom portion 61a, an inner side wall 61b, and an outer side wall 61c. The side wall 61b is provided upright above the bottom 61a along the inner edge of the bottom 61a. The side wall 61c is erected upward from the bottom 61a along the outer edge of the bottom 61a. That is, the cross-sectional shape of each side portion of the frame member 61 is substantially U-shaped with the opening facing upward, and an opening is formed between the side wall 61b and the side wall 61c on the upper surface of the frame member 61. A groove 65 is provided. The groove 65 is provided along the upper surface of the frame member 61 in plan view.

  The heat insulating material 63 has a substantially rectangular parallelepiped shape, and is inserted into the groove 65 so that the upper surface is substantially horizontal. A plurality of heat insulating materials 63 are arranged in a substantially square shape along the frame member 61 and the groove 65 (see FIG. 6). The height of each heat insulating material 63 is higher than the depth of the groove 65, and the upper portion of the heat insulating material 63 protrudes above the groove 65. As a material of the heat insulating material 63, for example, ceramics may be used.

  In such a configuration, the holding plate 52 is supported on the pedestal 53 in a state where the lower peripheral edge portion of the holding plate 52 is placed on the upper surfaces of a plurality of heat insulating materials 63 arranged in a substantially square shape. The frame member 61 is not in contact with the holding plate 52, and only the heat insulating material 63 is brought into contact with the holding plate 52. Thus, since the heat insulating material 63 is sandwiched between the holding plate 52 and the gantry 53, heat is conducted from the heat accumulator 33 to the bottom 30c of the casing 30 via the holding plate 52 and the gantry 53 and escapes to the outside. This can be suppressed. Therefore, heat storage of the heat storage body 33 can be performed efficiently.

  The frame support members 62 are arranged side by side along the peripheral edge adjacent to the cylindrical portion 30a at the bottom 30c of the casing 30. The lower end portion of each frame support member 62 is attached to the inclined upper surface of the bottom portion 30 c of the casing 30, and the upper end portion is attached to the lower surface of the bottom portion 61 a of the frame member 61. The upper end portion and the lower end portion of the frame support member 62 are fixed to the frame member 61 and the bottom portion 30c by welding or the like.

  The peripheral part of the heat storage body holding body 51 (the peripheral part of the holding plate 52 and the gantry 53) may be provided inside or outside the internal heat insulating material 45, but the side wall ( The cylindrical part 30a) is preferably not in contact. The gap provided between the holding plate 52 and the cylindrical portion 30a is, for example, more than the amount of movement due to thermal expansion of the end of the vertical plate 52a and the end of the horizontal plate 52b under the temperature in the casing 30 during heat storage. It is preferable to enlarge it. That is, it is preferable that the vertical plate 52a and the horizontal plate 52b do not come into contact with the cylindrical portion 30a or the casing 30 is not pushed from the inside by the holding plate 52 even if the vertical plate 52a and the horizontal plate 52b extend sideways due to thermal expansion. In this case, it is possible to prevent stress from being generated between the holding plate 52 and the casing 30, and it is possible to prevent the holding plate 52 and the casing 30 from being damaged by the stress. Moreover, it is preferable that a gap is also formed between the gantry 53 and the inner surface of the cylindrical portion 30a. That is, even if the gantry 53 (side wall 61c) is deformed so as to be directed toward the cylindrical portion 30a due to thermal expansion, it is preferable not to contact the cylindrical portion 30a. Thereby, it can prevent that a stress generate | occur | produces between the mount frame 53 and the casing 30, and can prevent the mount frame 53 and the casing 30 from being damaged.

  As described above, the heat storage body 33 and the heat storage body holding body 51 are supported by the bottom 30c of the casing 30, and a load is applied from the heat storage body holding body 51 to the bottom 30c. The heat storage body 33 and the heat storage body holding body 51 are not in contact with the side wall of the casing 30, and a load is applied to the side wall of the casing 30 from the heat storage body 33 and the heat storage body holding body 51. Thus, damage to the side wall of the casing 30 can be prevented.

  Since the holding plate 52, the frame member 61, and the heat insulating material 63 are not fixed to each other, even if the holding plate 52, the base 53, and the heat insulating material 63 are thermally expanded when the inside of the casing 30 is heated, It is possible to deform while shifting from each other. Therefore, it is possible to prevent the holding plate 52, the frame member 61, and the heat insulating material 63 from being damaged by stress.

  As shown in FIG. 3 and FIG. 4, two columns 35 of the casing 30 are provided for each peripheral portion of the bottom portion 30 c, a total of eight, and are arranged so as to surround the outlet port 32. Yes. Each support column 35 has a substantially straight bar shape, and is provided with its length direction substantially vertical. The upper end portion of each column 35 is fixed to the outer surface of the bottom portion 30c, that is, the lower surface by welding or the like. The lower end of each column 35 is placed on a mounting table or a floor surface outside the heat accumulator 15.

  Each support column 35 is preferably disposed directly below the frame member 61, that is, at a position overlapping the frame member 61 in plan view. In addition, it is preferable to be disposed just below the frame support member 62, that is, on a substantially vertical central axis A substantially the same as the frame support member 62 in a side view. In this way, the portion directly below the frame member 61 and the frame support member 62 in the bottom portion 30c can be reinforced intensively by the support column 35, and the bottom portion 30c is damaged by the load of the heat storage body 33, the holding plate 52, and the mount 53. Can be prevented. The loads of the heat storage body 33, the holding plate 52, and the gantry 53 can be received by the support column 35 with a good balance. Moreover, the load of the heat storage body 33, the holding plate 52, the pedestal 53, etc. can act on each column 35 in a substantially vertical direction, and each column 35 can be brought into a state of being pushed straight in the substantially vertical direction. That is, the column 35 is mainly subjected to compressive stress in the direction of the central axis A, and it is possible to suppress the occurrence of bending stress toward the outside or the inside of the gantry 53. Therefore, damage to the support column 35 and the bottom portion 30c can be prevented, and the heat accumulator 15 can be reliably supported.

  Next, a processing method in the processing apparatus 1 configured as described above will be described. First, before putting the object to be processed into the processing furnace 2, a pre-process for making the inside of the processing furnace 2 a reducing atmosphere and raising the atmosphere in the processing furnace 2 to a predetermined temperature is performed. That is, the inside of the processing furnace 2 is purged with a reducing atmosphere by exhausting the inside of the processing furnace 2 while supplying the reducing processing gas into the processing furnace 2 through the supply path 3. In addition, the heater 11 is operated, the processing gas passing through the supply path 3 is heated to a predetermined temperature by the heat generated by the heater 11, and the heated high-temperature processing gas is supplied into the processing furnace 2, thereby raising the inside of the processing furnace 2. Let warm. At this time, the high-temperature processing gas supplied from the supply path 3 to the processing furnace 2 is exhausted as exhaust gas from the processing furnace 2 through the exhaust path 4 and further introduced into the heat accumulator 15. In the heat accumulator 15, a part of the heat of the exhaust gas (process gas) is taken and stored in the heat accumulator 33.

  In the heat accumulator 15, the exhaust gas is introduced into the casing 30 from the discharge path 4 a through the introduction port 31 and diffused to the entire upper part of the heat accumulator 33 by the dispersion plate 47, and then between the heat accumulators 50 of the heat accumulator 33. Descends through. When the exhaust gas descends between the heat storage materials 50, the heat of the exhaust gas is transmitted to the heat storage material 50, the heat storage material 50 is heated, and the exhaust gas is cooled. The exhaust gas that has passed between the heat storage materials 50 flows out of the holding plate 52 through the communication ports 52c of the holding plate 52 and is led out from the casing 30 through the outlet 32 by the discharge passage 4b.

  Thus, the heat of the exhaust gas is stored in the heat storage material 50, but since the heat insulating material 63 is provided between the holding plate 52 that supports the heat storage material 50 and the mount 53, the heat of the heat storage body 33 is transferred from the casing 30 to the outside. The heat is stored efficiently without being lost.

  The exhaust gas lowered in temperature in the heat accumulator 15 is led out from the heat accumulator 15 and is again introduced into the supply path 3 as a processing gas by the operation of the blower 18. Then, after being heated again by the heater 11, it is supplied to the processing furnace 2. In this pre-process, the temperature of the exhaust gas from the heat accumulator 15 to the heat exchanger 10 in the discharge path 4 and the temperature of the processing gas introduced from the discharge path 4 to the supply path 3 are almost the same, or The temperature of the processing gas is slightly lower than the exhaust gas due to natural heat dissipation, and heat exchange is hardly performed in the heat exchanger 10.

  In this way, when the processing gas is heated by the heat of the heater 11 and a part of the heat generated by the heater 11 is carried to the heat accumulator 15 by the processing gas while the inside of the processing furnace 2 is in a reducing atmosphere at a predetermined temperature, The processing body is charged and the inside of the processing furnace 2 is sealed. And the reduction process (endothermic reaction process) process of the to-be-processed object in the processing furnace 2 is started. Even during the reduction process, the processing gas is circulated so as to pass through the supply path 3, the processing furnace 2, and the exhaust path 4 by the operation of the blower 18 while being heated by the heater 11.

In the processing furnace 2, when hydrogen in the processing gas is supplied to iron oxide in the object to be processed, moisture (H ₂ O) is generated due to a reduction reaction in which oxygen (O) is deprived from the iron oxide. Iron is reduced to iron.

  Here, since the reduction reaction between iron oxide and hydrogen generated in the processing furnace 2 is an endothermic reaction that takes away the surrounding heat, the temperature of the processing gas supplied from the supply path 3 into the processing furnace 2 is 2 is lower than the temperature of the exhaust gas discharged from inside. That is, a part of the heat given to the processing gas by the heat generated by the heater 11 is absorbed in the reduction reaction, and the heat storage 15 is introduced with the exhaust gas cooled by the heat absorption. On the other hand, the heat collected in the heat accumulator 15 stores the heat collected in the previous step. Therefore, when the exhaust gas passes through the heat storage material 33, the exhaust gas is stored with heat, and the exhaust gas is heated. In this way, the exhaust gas whose temperature is higher than that immediately after being discharged from the processing furnace 2 is introduced from the heat accumulator 15 into the heat exchanger 10.

  In the heat exchanger 10, heat exchange is performed between the exhaust gas heated in the heat accumulator 15 and the processing gas passing through the supply path 3, and heat is applied from the exhaust gas to the processing gas. That is, between the heat accumulator 15 and the heat exchanger 10, the exhaust gas functions as a heat medium that carries the heat accumulated in the heat accumulator 15 to the heat exchanger 10 and transmits it to the processing gas. The exhaust gas is cooled by the cold heat of the processing gas.

  The exhaust gas derived from the heat exchanger 10 is supplied as a processing gas from the discharge path 4 to the supply path 3 via the blower 18.

  In the supply path 3, the processing gas is introduced from the blower 18 to the heat exchanger 10, and heat exchange is performed with the exhaust gas as described above. That is, the heat of exhaust gas is given to the processing gas, and the processing gas is heated.

  The processing gas heated in the heat exchanger 10 is heated to a higher temperature by the heater 11 and then supplied to the processing furnace 2. Here, since the processing gas is preheated in the heat exchanger 10 before being heated by the heater 11, the amount of heat generated by the heater 11 required to raise the temperature of the processing gas to a predetermined temperature is determined by the regenerator. As compared with the case where the heat exchanger 15 and the heat exchanger 10 are not provided, the calorific value can be reduced. Therefore, the running cost such as the electricity charge of the heater 11 can be reduced. In particular, immediately after the object to be processed is put into the processing furnace 2 and the reduction process is started, the endothermic amount is large and the temperature of the exhaust gas rapidly decreases. Although it is difficult to shorten the time required to raise the temperature of the gas and the temperature of the processing gas supplied into the processing furnace 2 to a predetermined temperature, by preheating the processing gas with the heat accumulator 15 and the heat exchanger 10, The heater 11 can raise the temperature to a predetermined temperature in a short time, and the reduction process can be performed stably. Further, when a new process gas is supplied from the introduction path 23 to the supply path 3, the process gas can be passed through the heat exchanger 10 and preheated before being sent to the heater 11. The running cost of the heater 11 can be reduced.

  According to the processing apparatus 1, the exhaust gas discharged from the processing furnace 2 is introduced into the heat accumulator 15 while the heated processing gas is supplied to the processing furnace 2 before the reduction process of the object to be processed is started. By doing so, the heat of the exhaust gas can be stored. After the reduction treatment process is started, the heat stored in the heat accumulator 15 is used to preheat the treatment gas before being supplied to the treatment furnace 2, and then heated by the heater 11. Can supply. Therefore, even if an endothermic reaction occurs, the inside of the processing furnace 2 can be efficiently heated, and the load on the heater 11 can be reduced. Further, even if the temperature in the processing furnace 2 suddenly decreases immediately after the start of the reduction process, the temperature in the processing furnace 2 can be quickly raised by heating the processing gas using the heat stored in the heat accumulator 15. Can do. Thereby, the efficiency of the reduction reaction can be improved.

  Further, in the heat accumulator 15, the heat storage body 33 is held by the heat storage body holding body 51, and the heat storage body holding body 51 is prevented from contacting the side wall of the casing 30, thereby preventing the side wall of the casing 30 from being damaged. it can. Therefore, durability and heat resistance can be improved and the life of the heat accumulator 15 can be extended. Furthermore, by providing the heat storage body 51 with the heat insulating material 65, it is possible to prevent heat from escaping from the heat storage body 33 to the casing 30. Therefore, heat storage can be performed efficiently.

  The preferred embodiments of the present invention have been described above, but the present invention is not limited to such examples. It is obvious for those skilled in the art that various changes and modifications can be conceived within the scope of the technical idea described in the claims. It is understood that it belongs to. For example, in the above embodiments, the apparatus and method for reducing iron oxide have been described, but the present invention can also be applied to apparatuses and methods for reducing other oxides. For example, the present invention can be applied to an apparatus and method for obtaining molybdenum (Mo) by reducing molybdenum oxide powder, and an apparatus and method for obtaining tungsten (W) by reducing tungsten oxide powder.

  The present inventors conducted an experiment of a processing method using the processing apparatus 1. As shown in FIG. 7, in the supply path 3, thermometers T <b> 1 and T <b> 2 are provided between the heat exchanger 10 and the heater 11 and between the heater 11 and the processing furnace 2, respectively. Further, in the discharge path 4, thermometers T3 and T4 are provided between the processing furnace 2 and the heat accumulator 15, between the heat accumulator 15 and the heat exchanger 10, and between the heat exchanger 10 and the blower 18, respectively. , T5. Then, after the temperature in the processing furnace 2 was set to 610 ° C. in the previous process, the target value of the temperature in the processing furnace 2 was set to 610 ° C. in the reduction processing process, and the reduction process was started.

  Immediately after starting the reduction reaction, the measured value of the thermometer T3 dropped to about 130 ° C., but then gradually increased to about 560 ° C. When the measured value of thermometer T3 is 560 ° C., the measured value of thermometer T4 is 608 ° C., the measured value of thermometer T5 is 65 ° C., the measured value of thermometer T1 is 570 ° C., and the measured value of thermometer T2 is It was 610 ° C. That is, the temperature of the processing gas sent from the blower 18 at about 65 ° C. can be raised to a high temperature of about 570 ° C. by the heat exchanger 10, and the load on the heater 11 can be greatly reduced.

The present invention is applicable for example iron, molybdenum, the processing how that used in the production of various metal such as tungsten.

It is explanatory drawing which showed the structure of the processing apparatus concerning this Embodiment. It is a schematic longitudinal cross-sectional view of a heat storage device. It is the bottom view which showed the state which looked at the thermal accumulator from the bottom part side. It is the longitudinal cross-sectional view which expanded and showed the thermal storage body holding body vicinity of the thermal storage device. It is a top view of a thermal storage body holder. It is a schematic perspective view of a mount. It is explanatory drawing which showed the position which provided the thermometer in experiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Processing apparatus 2 Processing furnace 3 Supply path 4 Discharge path 10 Heat exchanger 11 Heater 15 Heat accumulator 20 Circulation line 30 Casing 31 Inlet port 32 Outlet port 33 Heat storage body 51 Heat storage body holder 52 Holding plate 53 Base 61 Frame member 62 Frame Support member 63 Insulation

Claims (4)

A processing method for processing an object by an endothermic reaction,
  Before introducing the object to be processed into the processing furnace, the processing furnace is exhausted while supplying the heated processing gas into the processing furnace, and the heat of the exhaust gas exhausted from the processing furnace is stored in the regenerator. ,
  Thereafter, the object to be processed is put into the processing furnace, and the endothermic reaction process of the object to be processed is started.
  When performing the endothermic reaction treatment, exhaust gas exhausted from the processing furnace is passed through the regenerator, the temperature is increased by the heat storage,
  The process gas is heated and supplied into the process furnace by causing heat exchange between the exhaust gas heated by the heat storage and the process gas supplied into the process furnace. Processing method. The processing method according to claim 1, wherein the processing gas heated by the heat exchange is further heated by a heater and then supplied into the processing furnace. The processing method according to claim 1, wherein the exhaust gas is supplied as a processing gas to the processing furnace. The object to be treated contains an oxide,
  The process gas contains hydrogen;
  The processing method according to claim 1, wherein the endothermic reaction is a reduction reaction for reducing an oxide.

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