Heating device

Abstract

This heating device includes: a microwave irradiation unit 3 configured to irradiate a heated object 14 with microwaves; and a recovery unit 105 configured to recover a fluid generated from the heated object 14 that is irradiated with microwaves. The microwaves are, for example, electromagnetic waves having a frequency of 300 MHz to 30 GHz inclusive. The heated object 14 includes, for example, a metal. The heated object 14 also includes, for example, a non-metal such as an oil, organic matter, water, or the like. When the heated object 14 is irradiated with microwaves, the heated object 14 is heated, and a non-metal having a melting point and a boiling point lower than those of the metal becomes a fluid and separates from the heated object.

Description

heating device

[0001] Some aspects of the present invention relate to a heating device.

[0002] When heating an object to be heated, the object to be heated may be irradiated with microwaves.

[0003] JP 2012-158790 A JP 2017-145151 A JP 2009-035776 A JP 2013-216943 A JP 2017-145151 A International Publication No. 2022 / 195989 International Publication No. 2022 / 196681

[0004] An object of some aspects of the present invention is to provide a heating device that can improve the heating efficiency of a heating target by microwave irradiation.

[0005] The heating device according to the embodiment includes a microwave irradiation unit configured to irradiate microwaves onto an object to be heated, and a recovery unit configured to recover a fluid generated from the object to be heated that has been irradiated with microwaves.

[0006] In the heating device, the object to be heated may be metal.

[0007] In the heating device described above, the fluid may be a liquid, and the recovery section may include a liquid recovery section configured to recover the liquid.

[0008] In the heating device, the liquid recovery section may be disposed below the heating target in the direction of gravity.

[0009] In the heating device described above, the liquid recovery section may include a drain pan that receives the liquid.

[0010] In the heating device described above, the liquid recovery section may further include a drain pipe connected to the drain pan and through which the liquid flows.

[0011] In the heating device described above, the liquid recovery section may further include a tank connected to the drain pipe and configured to store the liquid.

[0012] In the heating device described above, the fluid may be a gas, and the recovery section may include a gas recovery section configured to recover the gas.

[0013] In the heating device described above, the gas recovery section may include a gas recovery pipe connected to an irradiation chamber in which a heating target to be irradiated with microwaves is placed.

[0014] In the heating device, the gas recovery section may include a liquefaction device that liquefies the recovered gas. The liquefaction device may cool and liquefy the recovered gas.

[0015] The heating device may further include a holding member that holds the heating target and that is provided with an opening that allows the fluid to pass through to the recovery section.

[0016] In the heating device, the holding member may rotate.

[0017] In the heating device, the holding member may move in a parallel manner.

[0018] In the heating device, the holding member may be a stage, and the object to be heated may be placed on the stage.

[0019] In the heating device, the holding member may have a hollow shape, and the object to be heated may be placed inside the holding member.

[0020] In the heating device, the holding member having a hollow shape may rotate.

[0021] The heating device may further include a transport device that transports the heating target to the microwave irradiator.

[0022] In the heating device, the conveying device may include a pushing unit configured to push the heating target.

[0023] In the heating device, the transport device may include a roller conveyor.

[0024] The heating device may further include an irradiation chamber in which a heating target to be irradiated with microwaves is placed, and a pre-heating chamber connected to the irradiation chamber, and the heating target before being irradiated with microwaves is placed in the pre-heating chamber.

[0025] The heating device may further include a gas environment adjusting device that makes the gas environment in the irradiation chamber and the gas environment in the pre-heating chamber the same.

[0026] The heating device may further include an irradiation chamber in which the object to be heated to be irradiated with microwaves is placed, and a post-heating chamber connected to the irradiation chamber, and the object to be heated after being irradiated with microwaves may be placed in the post-heating chamber.

[0027] The heating device may further include a gas environment adjusting device that makes the gas environment in the irradiation chamber the same as the gas environment in the post-heating chamber.

[0028] The heating device may further include a supply device configured to supply the heating target to the microwave irradiation region before being irradiated with microwaves.

[0029] In the heating device, the fluid may be at least one of oil and water.

[0030] According to the present invention, it is possible to provide a heating device that can improve the efficiency of heating an object by irradiating microwaves.

[0031] FIG. 1 is a schematic diagram of a heating device according to an embodiment. FIG. 2 is a schematic diagram of a heating device according to an embodiment. FIG. 3 is a schematic diagram of a heating device according to an embodiment. FIG. 4 is a schematic diagram of a heating device according to an embodiment. FIG. 5 is a schematic diagram of a heating device according to an embodiment. FIG. 6 is a schematic diagram of a heating device according to an embodiment. FIG. 7 is a schematic diagram of a heating device according to an embodiment. FIG. 8 is a schematic diagram of a heating device according to an embodiment. FIG. 9 is a schematic diagram of a heating device according to an embodiment. FIG. 10 is a schematic diagram of a heating device according to an embodiment. FIG. 11 is a schematic diagram of a heating device according to an embodiment. FIG. 12 is a schematic diagram of a heating device according to an embodiment.

[0032] Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the drawings are schematic. Therefore, specific dimensions and the like should be determined in light of the following description. Furthermore, it goes without saying that the dimensional relationships and ratios between the drawings may differ.

[0033] 1, the heating device according to the embodiment includes a microwave irradiating unit 3 configured to irradiate a heating target 14 with microwaves, and a recovery unit 105 configured to recover a fluid generated from the heating target 14 irradiated with the microwaves. The microwaves are electromagnetic waves having a frequency of, for example, 300 MHz or more and 30 GHz or less.

[0034] The heating target 14 includes, for example, a metal. The heating target 14 includes, for example, a ceramic. The heating target 14 also includes, for example, a non-metal such as oil, an organic substance, and water. In the present disclosure, oil includes an emulsion. When microwaves are irradiated to the heating target 14, the heating target 14 is heated, and non-metals with lower melting points and boiling points than metals and ceramics become fluid and leave the heating target. The heating target 14 may be reduced by being irradiated with microwaves. The heating target 14 may also be sintered or melted and solidified by being irradiated with microwaves.

[0035] Fluids generated from the heating target 14 include liquids and gases. The recovery unit 105 may include a liquid recovery unit 106 configured to recover liquids. Examples of liquids include water, oil, and organic matter. The recovery unit 105 may include a gas recovery unit 107 configured to recover gases. Examples of gases include vaporized water, vaporized oil, and vaporized organic matter.

[0036] The oil may be water-soluble or water-insoluble. The oil may contain at least one of a surfactant, a rust inhibitor, and a preservative. The oil may be mixed with water to form an emulsion. Examples of oils include cutting oils and mold release agents. Examples of cutting oils include mineral oils, animal and vegetable oils, synthetic oils, and mineral oils, as well as mixtures thereof.

[0037] The oil may also be oil adhering to the object to be heated 14 from a machine that processes the object to be heated 14, such as rolling oil, extrusion oil used in extrusion processing, drawing oil used in drawing processing, press oil used in press processing, forging oil used in forging processing, hydraulic oil leaking from a processing machine during metal processing or cutting, cooling oil, rust prevention oil, and lubricating oil.

[0038] Examples of organic substances include surfactants and silicone oils.

[0039] 2, the liquid recovery unit 106 is disposed below the heating target 14 in the direction of gravity when microwaves are irradiated. The liquid recovery unit 106 may include a drain pan 15 that receives the liquid that has separated from the heating target 14, a drain pipe 17 that is connected to the drain pan 15 and through which the liquid flows, and a tank 21 that is connected to the drain pipe 17 and stores the liquid 28. A valve 17a may be provided between the drain pan 15 and the drain pipe 17. The valve 17a prevents outside air from entering an irradiation chamber 36, which will be described later.

[0040] The heating device according to the embodiment may further include a holding member 425 that holds the heating target 14 when irradiated with microwaves. The holding member 425 is, for example, a stage on which the heating target 14 is placed. The holding member 425 is provided with, for example, an opening that allows liquid that has been released from the heating target 14 that has been irradiated with microwaves and heated to pass through to the liquid recovery unit 106. There may be one or more openings.

[0041] The liquid that has been released from the heating target 14 that has been irradiated with microwaves and heated falls into the drain pan 15 through the opening in the holding member 425. The liquid that has accumulated in the drain pan 15 is sent to the tank 21 through the drain pipe 17.

[0042] The heating device according to the embodiment may further include an irradiation chamber 36 in which the heating target 14 to be irradiated with microwaves is placed. The microwave irradiator 3 irradiates microwaves to the heating target 14 placed in the irradiation chamber 36. The irradiation chamber 36 can seal the interior from the outside, for example, when the microwave irradiator 3 irradiates microwaves. The bottom of the irradiation chamber 36 may serve as a drain pan 15.

[0043] The irradiation chamber 36 is provided with, for example, an entrance door 410A for carrying the heating target 14 into the irradiation chamber 36 and an exit door 410B for carrying the heating target 14 out of the irradiation chamber 36.

[0044] The gas recovery unit 107 may include a gas recovery pipe 20 connected to the irradiation chamber 36, a suction pump 24 that sucks gas in the irradiation chamber 36 into the gas recovery pipe 20, and a liquefaction device 25 that liquefies the recovered gas. Gas released from the heating target 14 that has been heated by microwave irradiation is recovered from the irradiation chamber 36 by the suction pump 24 via the gas recovery pipe 20 and sent to the liquefaction device 25. The liquefaction device 25 liquefies the recovered gas by, for example, cooling the recovered gas.

[0045] The heating target 14 may include a metal element or a metal compound such as an alloy. Examples of metals include iron (Fe), nickel (Ni), copper (Cu), gold (Au), silver (Ag), aluminum (Al), cobalt (Co), tungsten (W), titanium (Ti), chromium (Cr), molybdenum (Mo), beryllium (Be), magnesium (Mg), tin (Sn), cerium (Ce), lead (Pb), mercury (Hg), sodium (Na), bismuth (Bi), and gallium (Ga).

[0046] The sintering temperature of iron (Fe) is, for example, 1200°C. The melting point of iron (Fe) is 1538°C. The sintering temperature of nickel (Ni) is, for example, 1200°C. The melting point of nickel (Ni) is 1495°C. The sintering temperature of copper (Cu) is, for example, 800°C. The melting point of copper (Cu) is 1085°C. The sintering temperature of gold (Au) is, for example, 800°C. The melting point of gold (Au) is 1064°C. The sintering temperature of silver (Ag) is, for example, 750°C. The melting point of silver (Ag) is 962°C. The sintering temperature of aluminum (Al) is, for example, 500°C. The melting point of aluminum (Al) is 660°C. The sintering temperature of cobalt (Co) is, for example, 1100°C. The melting point of cobalt (Co) is 1455°C.

[0047] The heating target 14 may contain one type of metal or multiple types of metals. Examples of metal compounds include, but are not limited to, alloys of multiple metal elements, alloys of metal elements and non-metal elements, metal oxides, metal hydroxides, metal chlorides, metal carbides, metal borides, and metal sulfides. The metal raw material may contain, as alloy components, for example, silicon (Si), manganese (Mn), chromium (Cr), nickel (Ni), carbon (C), boron (B), copper (Cu), aluminum (Al), titanium (Ti), niobium (Nb), vanadium (V), zinc (Zn), antimony (Sb), palladium (Pd), lanthanum (La), gold (Au), potassium (K), cadmium (Cd), indium (In), molybdenum (Mo), and sulfur (S).

[0048] The shape and size of the heating target 14 are not particularly limited. The heating target 14 may be a solid or may be made of powder. The heating target 14 may be plate-shaped or sheet-shaped. The heating target 14 may include a compact of metal powder. The heating target 14 may include metal fragments. The heating target 14 may be a briquette.

[0049] When the heating target 14 is a compact of a metal material, a pressure of, for example, 1 MPa or more, 100 MPa or more, or 200 MPa or more and 2000 MPa or less, 1900 MPa or less, or 1800 MPa or less may be applied to the metal raw material when the metal raw material is molded into a compact. By applying pressure, the metal solid produced by heating the heating target 14 and sintering or melt-solidifying the metal tends to become dense. Examples of pressure application methods include uniaxial molding, cold isostatic pressing (CIP) molding, hot isostatic pressing (HIP) molding, and roller pressing.

[0050] The holding member 425 may contain a heating promoter that promotes heating of the heating target 14 irradiated with microwaves.

[0051] The heating accelerator may include an absorbing material that absorbs microwaves in at least a part of a temperature range that is lower than the temperature range in which the metal raw material of the heating target 14 absorbs microwaves. The absorbing material has a melting point higher than the melting point of the metal raw material. At least a part of the temperature range in which the absorbing material absorbs microwaves is lower than the temperature range in which the metal raw material absorbs microwaves. The temperature range in which the metal raw material absorbs microwaves is, for example, 300°C to 1200°C, 450°C to 1100°C, or 600°C to 800°C. The temperature range in which the absorbing material absorbs microwaves is, for example, 25°C to 1000°C, 50°C to 1000°C, 75°C to 1000°C, 100°C to 1000°C, 250°C to 900°C, or 400°C to 600°C.

[0052] It is preferable that at least a part of the temperature range in which the absorbing material absorbs microwaves overlaps with the temperature range in which the metal raw material absorbs microwaves. The absorbing material absorbs microwaves in a temperature range that is at least partially lower than the temperature range in which the metal raw material absorbs microwaves, and therefore generates heat faster than the metal raw material. Therefore, the absorbing material can heat the metal raw material before the temperature reaches the temperature range in which the metal raw material absorbs microwaves.

[0053] Therefore, when the heating promoter contains an absorbing material, the temperature of the metal raw material quickly reaches a temperature range in which microwaves are absorbed, thereby shortening the heating time of the metal raw material. Furthermore, since the absorbing material absorbs microwaves in a temperature range that is at least partially lower than the temperature range in which the metal raw material absorbs microwaves, it is possible to prevent the heating promoter from being heated more than necessary. Therefore, the shape of the heating promoter containing the absorbing material can be stable even while the metal raw material irradiated with microwaves is being sintered or melted.

[0054] The absorbing material includes, for example, a carbon material. Examples of carbon materials include, but are not limited to, carbon black, amorphous carbon, graphite, silicon carbide, carbon resin, and metal carbide. The absorbing material may include a metal raw material, a metal nitride, a metal oxide, a metal boride, or the like that absorbs microwaves in a temperature range that is at least partially lower than the temperature range in which the metal raw material to be heated absorbs microwaves. The absorbing material may also be a compound of these. It is preferable that the absorbing material does not contain a volatile component. By not containing a volatile component in the absorbing material, it is possible to prevent microwaves from being absorbed by the volatile component.

[0055] The heating promoter may contain an insulating material that is more microwave-transparent and less microwave-absorbent than the metal raw material. The insulating material has a melting point higher than that of the metal raw material. The insulating material generates less heat when irradiated with microwaves due to its low microwave absorption, thereby exhibiting a heat-insulating effect. Furthermore, because the insulating material has a higher melting point than the metal raw material, its shape remains stable even when irradiated with microwaves. Therefore, the heating promoter containing the insulating material can remain stable in shape even while the metal raw material irradiated with microwaves is being sintered or melted.

[0056] The thermal insulating material may include a metal oxide or a metalloid oxide. Examples of metal and metalloid oxides include, but are not limited to, aluminum oxide (Al2O3), silicon oxide (SiO2), magnesium oxide (MgO), zirconium oxide (ZrO2), and titanium oxide (TiO2). For example, the melting point of aluminum oxide (Al2O3) is 2072°C. The melting point of silicon oxide (SiO2) is 1710°C. The melting point of magnesium oxide (MgO) is 2852°C. The thermal insulating material may be a compound of these.

[0057] The heating promoter may include a reducing material that reduces the metal raw material. The reducing material has a melting point higher than the melting point of the metal raw material. Examples of reducing materials include carbon and silicon carbide. Carbon materials used as absorbent materials may also function as reducing materials.

[0058] The heating promoter may consist of only an insulating material, only an absorbing material, only a reducing material, a mixture of an insulating material and an absorbing material, a mixture of an absorbing material and a reducing material, a mixture of a reducing material and an insulating material, or a mixture of an insulating material, an absorbing material, and a reducing material. The insulating material, the absorbing material, and the reducing material may have overlapping properties and functions. For example, a carbon material can function as both an absorbing material and a reducing material.

[0059] As shown in Fig. 3, when microwaves are irradiated onto the target 14 to be heated, a contact member 420 containing a heating promoter may be brought into contact with the target 14 to be heated. The contact member 420 contacts, for example, the upper surface of the target 14 to be heated. The contact member 420 may be movable in the direction of gravity. The contact member 420 may contain a heating promoter. By sandwiching the target 14 to be heated between a holding member 425 containing a heating promoter and the contact member 420 containing a heating promoter, heating of the target 14 to be heated is promoted.

[0060] In order to uniformly heat the heating target 14, the heating target 14 may be rotated relative to the microwave irradiation unit 3. For example, the heating device according to the embodiment further includes a turntable 440 that rotates the heating target 14 placed on the holding member 425. A shaft 430 is connected to the turntable 440, and the turntable 440 rotates around the shaft 430. The longitudinal direction of the shaft 430 is, for example, parallel to the irradiation window of the microwave irradiation unit 3 and perpendicular to the main traveling direction of the microwaves irradiated from the microwave irradiation unit 3.

[0061] When the target 14 to be heated is rotated on the turntable 440, the contact member 420 in contact with the upper surface of the target 14 to be heated may be rotated. The contact member 420 may be rotated passively in accordance with the rotation of the target 14 to be heated. A shaft 435 may be connected to the contact member 420. An opening may be provided in the center of the contact member 420, and the shaft 435 may be inserted into the opening. The irradiation chamber 36 may be provided with a sleeve 431 into which the shaft 435 is inserted. The longitudinal directions of the shaft 435 and the sleeve 431 are parallel to the shaft 430, and the centers of the shafts 430 and 435 are on the same line. The contact member 420 rotates around the shaft 435.

[0062] When the heating target 14 contains a metal oxide, the metal oxide is reduced by irradiating the heating target 14 with microwaves. When the heating target 14 contains a metal, a dense sintered body is likely to be obtained by heating the heating target 14 to a temperature above the sintering temperature and close to the melting point. Therefore, the heating target 14 may be heated to 1400°C or higher, or 1500°C or higher, using microwaves. When the heating target 14 is to be melted and solidified, it is sufficient to heat the heating target 14 to a temperature above the melting point.

[0063] When the heating target 14 is heated, components contained in the heating target 14 liquefy and vaporize, and liquid and gas may be generated from the heating target 14. If the liquid and gas generated from the heating target 14 continue to exist in the irradiation chamber 36, they may adhere to the heating target 14 and the inner wall of the irradiation chamber 36. Furthermore, when microwave irradiation is terminated and the temperature inside the irradiation chamber 36 drops, the liquid and gas that have adhered to the heating target 14 and the inner wall of the irradiation chamber 36 may solidify.

[0064] The liquid and gas generated from the heating target 14 may be impurities. Therefore, it is not preferable for the liquid and gas generated from the heating target 14 to adhere to the heating target 14 again. Furthermore, if the liquid and gas generated from the heating target 14 adheres to the microwave-transparent window of the microwave irradiation unit 3, the microwave irradiation efficiency will decrease, which is not preferable. Furthermore, if a measuring instrument such as a thermometer is provided in the irradiation chamber 36, it is not preferable for the liquid and gas generated from the heating target 14 to adhere to the measuring instrument, as this may reduce the measurement accuracy of the measuring instrument.

[0065] Furthermore, if the heating target 14 contains oil before being heated, toxic gases such as benzene and toluene may be generated when the oil is heated.

[0066] However, the heating device according to the embodiment includes a recovery unit configured to recover fluid generated from the heating target 14 irradiated with microwaves, and therefore can prevent liquid and gas generated from the heating target 14 from adhering to the heating target 14, the inner wall of the irradiation chamber 36, the microwave-transparent window, and measuring equipment. It can also prevent toxic gas from diffusing around the heating device.

[0067] The heating device according to the embodiment may further include a pre-heating chamber 400 connected to the irradiation chamber 36. The heating target 14 is placed in the pre-heating chamber 400 before being irradiated with microwaves. The pre-heating chamber 400 is provided with a loading door (not shown) for loading the heating target 14 from the outside into the chamber. A loading door 410A is placed between the pre-heating chamber 400 and the irradiation chamber 36, and the loading door 410A is opened when the heating target 14 is moved from the pre-heating chamber 400 to the irradiation chamber 36.

[0068] The pre-heating chamber 400 can function as a load lock chamber. For example, the heating device may include a gas environment adjustment device that makes the gas environment in the irradiation chamber 36 the same as the gas environment in the pre-heating chamber 400. For example, the irradiation chamber 36 is provided with a gas inlet pipe 255 and a gas outlet pipe 260, and the pre-heating chamber 400 is provided with a gas inlet pipe 256 and a gas outlet pipe 261.

[0069] With the irradiation chamber 36 sealed, the gas inside the irradiation chamber 36 is discharged through the gas discharge pipe 260 and a gas of a desired composition is introduced into the irradiation chamber 36 through the gas introduction pipe 255, thereby making it possible to set desired gas conditions inside the irradiation chamber 36. Furthermore, with the pre-heating chamber 400 sealed, the gas inside the pre-heating chamber 400 is discharged through the gas discharge pipe 261 and a gas of a desired composition is introduced into the pre-heating chamber 400 through the gas introduction pipe 256, thereby making it possible to set the gas inside the pre-heating chamber 400 to desired conditions.

[0070] The gas introduced into the pre-heating chamber 400 and the irradiation chamber 36 may be an inert gas. Examples of the inert gas include argon (Ar) and helium (He). The gas introduced into the pre-heating chamber 400 and the irradiation chamber 36 may be a neutral gas. Examples of the neutral gas include nitrogen (N), dry hydrogen (H), and ammonia (NH). The gas introduced into the pre-heating chamber 400 and the irradiation chamber 36 may be a reducing gas. Examples of the reducing gas include hydrogen (H), carbon monoxide (CO), and hydrocarbon gases (CH, C, H, C). 10 etc.)

[0071] After the heating target 14 is placed in the pre-heating chamber 400, the pre-heating chamber 400 is sealed, and the gas conditions in the pre-heating chamber 400 are made the same as the gas conditions in the irradiation chamber 36. Thereafter, the loading door 410A between the pre-heating chamber 400 and the irradiation chamber 36 is opened, the heating target 14 is moved into the irradiation chamber 36, and the loading door 410A is closed, thereby preventing outside air from entering the irradiation chamber 36.

[0072] The bottom surfaces of the pre-heating chamber 400 and the irradiation chamber 36 may form a continuous stage 1. The heating device according to the embodiment may further include a transport device that moves the heating target 14 from the pre-heating chamber 400 into the irradiation chamber 36. The transport device may include a pushing unit 11 configured to push the heating target 14 from the pre-heating chamber 400 toward the irradiation chamber 36. The pushing unit 11 includes, for example, a rod, and moves back and forth between the pre-heating chamber 400 and the irradiation chamber 36.

[0073] The heating device according to the embodiment may further include a post-heating chamber 401 connected to the irradiation chamber 36. The heating target 14a after being irradiated with microwaves is placed in the post-heating chamber 401. An outlet door 410B is placed between the irradiation chamber 36 and the post-heating chamber 401, and the outlet door 410B is opened when the heating target 14a is moved from the irradiation chamber 36 to the post-heating chamber 401. The post-heating chamber 401 is provided with an outlet door 411 for carrying the heating target 14a from the inside to the outside.

[0074] The post-heating chamber 401 can function as a load lock chamber. For example, the heating device may include a gas environment adjusting device that makes the gas environment in the irradiation chamber 36 and the gas environment in the post-heating chamber 401 the same. For example, the post-heating chamber 401 is provided with a gas inlet pipe 257 and a gas outlet pipe 262. With the post-heating chamber 401 sealed, the gas in the post-heating chamber 401 is exhausted through the gas outlet pipe 262, and a gas of a desired composition is introduced into the post-heating chamber 401 through the gas inlet pipe 257, thereby making it possible to set the gas in the post-heating chamber 401 to a desired condition.

[0075] Before the heating target 14a is transferred from the irradiation chamber 36 to the post-heating chamber 401, the post-heating chamber 401 is sealed, and the gas conditions in the post-heating chamber 401 are made the same as the gas conditions in the irradiation chamber 36. Thereafter, the transfer door 410B between the irradiation chamber 36 and the post-heating chamber 401 is opened, the heating target 14a is moved into the post-heating chamber 401, the transfer door 410B is closed, and then the transfer door 411 of the post-heating chamber 401 is opened to transfer the heating target 14a from the post-heating chamber 401, thereby making it possible to prevent outside air from entering the irradiation chamber 36.

[0076] The heating device according to the embodiment may further include a transport device that moves the heating target 14 a from inside the post-heating chamber 401 to the outside. The transport device may include a caterpillar conveyor 19 configured to transport the heating target 14 a from inside the post-heating chamber 401 to the outside.

[0077] In the heating apparatus according to the embodiment shown in Fig. 4, the irradiation chamber 36 is provided with an inlet 412 and an outlet 413. The heating apparatus shown in Fig. 4 includes a transport device for the heating target 14 that passes through the irradiation chamber 36 via the inlet 412 and the outlet 413. The transport device includes, for example, a roller conveyor 31 on whose upper surface the heating target 14 flows, and a pushing unit 11 that pushes the heating target 14 on the roller conveyor 31. A plurality of heating targets 14 may flow on the roller conveyor 31, and each of the plurality of heating targets 14 may be successively irradiated with microwaves within the irradiation chamber 36.

[0078] The microwave irradiator 3 may be provided at any position in the irradiation chamber 36. In the example shown in FIG. 4 , a microwave inlet is provided below the position in the irradiation chamber 36 where the heating target 14 is placed, in the direction of gravity. The microwave irradiator 3 may include, for example, a microwave generator 2 that generates microwaves, a microwave-transmitting window 103 through which the microwaves generated by the microwave generator 2 pass, and an air curtain supplier 6 that prevents volatile substances in the irradiation chamber 36 from adhering to the surface of the microwave-transmitting window 103. The microwave-transmitting window 103 is made of, for example, quartz glass. The air curtain supplier 6 prevents volatile substances from adhering to the microwave-transmitting window 103 by supplying an air curtain along the microwave-transmitting window 103. This is also true for the heating devices shown in the other figures.

[0079] The heating device may also include a fan 130 for diffusing microwaves within the irradiation chamber 36. As the fan 130 rotates and the surface of the fan 130 reflects the microwaves, the microwaves are agitated, and the positions of dead spots where microwave intensity is weak due to interference between microwaves within the irradiation chamber 36 change over time. This makes it possible to heat the heating target 14 uniformly. A fan may also be provided within the irradiation chamber 36 in the heating devices shown in the other figures.

[0080] The gas recovery unit 107 may include an analyzer 155 that analyzes the components of the gas recovered from the irradiation chamber 36. The analyzer 155 is connected to, for example, a pipe 150 that branches off from the gas recovery pipe 20. Examples of the analyzer 155 include a gas chromatograph (GC), a gas chromatograph mass spectrometer (GC / MS), an infrared spectrometer, and a Fourier transform infrared spectrometer. In the heating devices shown in the other figures, the gas recovery unit may also include an analyzer.

[0081] A porous partition 16 may be disposed between the position where the heating target 14 is disposed in the irradiation chamber 36 and the gas recovery unit 107. An example of the porous partition 16 is a punched metal. The porous partition 16 may be disposed between the position where the heating target 14 is disposed in the irradiation chamber 36 and the liquid recovery unit 106.

[0082] When the heating target 14a is a metal, the heating target 14a heated by a heating device may be poured into the molten metal 29 in the melting furnace 22. It is preferable that at least a portion of the metal contained in the molten metal is the same as at least a portion of the metal contained in the heated heating target 14a. The molten metal 29 may be monitored by a camera 26. For example, a metal casting may be produced by pouring the molten metal in which the heating target 14a has been melted into a mold and solidifying the molten metal in the mold.

[0083] For example, the heating target 14a heated by the heating device is reduced and free of an oxide film, making it suitable for immersion in molten metal. Furthermore, the heating target 14a heated by the heating device is suitable for immersion in molten metal because non-metals have been liquefied or vaporized and removed. Specifically, the heating target 14a from which oxides and non-metals have been removed is less likely to produce gas, steam explosions, fires, slag, and blisters when immersed in molten metal. Furthermore, the heating target 14a from which oxides have been removed is highly wettable by the molten metal and therefore easily sinks in the molten metal. The heating target 14a immersed in the molten metal dissolves quickly because heat is easily transferred to the interior.

[0084] The heated object may be thrown into the molten metal in the heating devices shown in figures other than Fig. 4. The other components of the heating device shown in Fig. 4 are the same as those of the heating devices shown in Figs. 2 and 3, and therefore will not be described here.

[0085] The method for transporting the heating target 14 is not particularly limited, and the heating target 14 may be directly transported by a transport device, or the heating target 14 placed in a tray 30 may be transported by a transport device as shown in Fig. 5. An opening 32 may be provided in the bottom surface of the tray 30 to allow passage of fluid generated from the heating target 14 irradiated with microwaves. One heating target 14 may be placed on one tray 30, or multiple heating targets 14 may be placed on one tray 30 as shown in Fig. 6.

[0086] As shown in Figures 5 and 6, the heating target 14 may be monitored by a camera 27 before being carried into the irradiation chamber 36. A temperature observation window 5 may be provided in the irradiation chamber 36, and the temperature inside the irradiation chamber 36 may be measured from outside the irradiation chamber 36 by a non-contact thermometer 4. The non-contact thermometer may be, for example, a radiation thermometer. The radiation thermometer measures the temperature of the measurement target based on the emissivity of the measurement target. The radiation thermometer may be, for example, a fiber-type radiation thermometer. The temperature of the heating target irradiated with microwaves and carried out of the irradiation chamber 36 may be measured by a non-contact thermometer 200. The other components of the heating device shown in Figures 5 and 6 are similar to those of the heating device shown in Figures 2 and 3, so description thereof will be omitted.

[0087] 7 , a holding member 426 that holds the heating target 14 may have a hollow shape. The holding member 426 has, for example, a cylindrical shape. The holding member 426 may include a portion 8 that contains a heating promoter and a portion 13 that does not contain a heating promoter. For example, the portion 8 of the holding member 426 that contains a heating promoter is placed in a position that is irradiated with microwaves, and the portion 13 of the holding member 426 that does not contain a heating promoter is placed in a position that is not irradiated with microwaves. The heating target 14 is placed inside the holding member 426. At least a portion of the heating target 14 may come into contact with the portion 8 of the holding member 426 that contains a heating promoter.

[0088] The portion 8 of the holding member 426 containing the heating promoter may be provided with an opening 9 for allowing the fluid generated from the heating target 14 to pass through to the outside of the holding member 426. The portion 13 of the holding member 426 not containing the heating promoter may be provided with an opening 113 for allowing the fluid generated from the heating target 14 to pass through to the outside of the holding member 426.

[0089] The holding member 426 having a hollow shape may be placed in the irradiation chamber 36 so that the central axis is perpendicular to the direction of gravity. The heating device may include a rotation device 18 that rotates the holding member 426 around the central axis of the holding member 426. The heating target 14 inside the holding member 426 may or may not rotate due to frictional force accompanying the rotation of the holding member 426. By irradiating the holding member 426 with microwaves while rotating the holding member 426, the holding member 426 is uniformly heated, and the heating target 14 inside the holding member 426 is also uniformly heated.

[0090] The shape of the heating target 14 is not particularly limited, but when the holding member 426 has a cylindrical shape, the heating target 14 may have a disk shape. For example, the heating target 14 may be disposed inside the holding member 426 so that at least a part of the outer periphery of the disk-shaped heating target 14 contacts the inner periphery of the holding member 426.

[0091] The heating target 14 may be pushed by the pushing unit 11 from an opening on the carry-in side of the hollow holding member 426, and the heating target 14 inside the holding member 426 may be moved toward an opening on the carry-out side. The heating target 14 may be supported by a support unit 111 from the opening on the carry-out side of the holding member 426 so that the heating target 14 inside the holding member 426 does not fall over. The pushing unit 11 and the support unit 111 move at a constant speed while sandwiching the heating target 14. The shaft of the pushing unit 11 and the shaft of the support unit 111 may pass through an opening provided in the irradiation chamber 36.

[0092] The irradiation chamber 36 may be provided with a carry-in hatch 115, and the heating target 14 may be carried into the irradiation chamber 36 through the carry-in hatch 115. The heating device may include a drive unit 116 that opens and closes the carry-in hatch 115. The heating target 14 carried into the irradiation chamber 36 is pushed by the push unit 11 and moves into the interior of a holding member 426 having a hollow shape.

[0093] An unloading hatch 117 may be provided in the irradiation chamber 36, and the heating target 14 may be unloaded from the irradiation chamber 36 through the unloading hatch 117. The heating device may include a drive unit 118 that opens and closes the unloading hatch 117. For example, the unloading hatch 117 may be provided on the bottom surface of the irradiation chamber 36. The heating target 14 that has been irradiated with microwaves is pushed by the push unit 11 to move from inside the holding member 426 onto the unloading hatch 117, and when the unloading hatch 117 opens, the heating target 14 drops below the irradiation chamber 36. The other components of the heating device shown in FIG. 7 are similar to those of the heating devices shown in FIGS. 2 and 3, and therefore will not be described.

[0094] As shown in Fig. 8, the heating device may include a supplier 166. The supplier 166 may be a feeder. The raw material 340 of the heating target 14 supplied from the supplier 166 may be carried into the irradiation chamber 36 by a pushing unit 325, and the raw material 340 may be irradiated with microwaves as the heating target 14. The pushing unit 325 may be held by a guide 335. An opening 9 may be provided in the stage 1 in the irradiation chamber 36 to allow a fluid generated from the heating target 14 to pass through.

[0095] 9 to 11 , the heating target 14 may be carried in and out from below the irradiation chamber 36 in the direction of gravity. As shown in Fig. 9 , the heating device includes a carry-in stage 34 below the irradiation chamber 36. The pushing unit 11 moves the heating target 14 on the carry-in stage 34 onto a movable stage 40. The heating device may include a stopper 41 to prevent the heating target 14 from falling from the movable stage 40.

[0096] The movable stage 40 is movable in the vertical direction. The movable stage 40 may be provided with an opening for allowing a fluid generated from the heating target 14 to pass through. As shown in FIG. 10 , when the heating target 14 is placed on the movable stage 40, the movable stage 40 rises and carries the heating target 14 into the irradiation chamber 36 through an opening in the bottom surface of the irradiation chamber 36. The heating device may include an enclosure 50 that surrounds the heating target 14 placed in the irradiation chamber 36. The enclosure 50 contains, for example, a heating promoter. A reflector 225 for reflecting microwaves may be provided inside the irradiation chamber 36.

[0097] The heating device may include a press 205 for applying pressure to the heating target 14 on the movable stage 40. An insulating layer 215 and a heat promotion member 220 may be provided on the pressure surface of the press 205. The heat promotion member 220 includes a heat promotion agent. For example, the insulating layer 215 is disposed between the pressure surface of the press 205 and the heat promotion member 220. The heat promotion member 220 comes into contact with the heating target 14 when the press 205 applies pressure to the heating target 14. The insulating layer 215 prevents heat from the heating target 14 and the heat promotion member 220, which have been heated by microwaves, from transferring to the press 205. The insulating layer 215 and the heat promotion member 220 may be fixed to the press 205 by a jig 230.

[0098] The heating device may irradiate the heating target 14 with microwaves while applying pressure to the heating target 14 with a press 205. The pressure applied to the heating target 14 is, for example, 1 MPa or more, 100 MPa or more, or 200 MPa or more, and 2000 MPa or less, 1900 MPa or less, or 1800 MPa or less, but is not particularly limited. By applying pressure to the heating target 14 while irradiating it with microwaves, the heating target 14 tends to become denser after heating. Furthermore, the press 205 may continue to apply pressure to the heating target 14 even after the irradiation of microwaves on the heating target 14 has finished.

[0099] The temperature of the heating target 14 being heated may be measured by thermometers 210a, 210b included in the press machine 205. After the heating target 14 has been irradiated with microwaves, the movable stage 40 descends and carries the heating target 14 out of the irradiation chamber 36, as shown in FIG. 11 . The pushing unit 43 pushes the heating target 14 on the lowered movable stage 40 onto the roller conveyor 48. The pushing unit 43 may be disposed on the pedestal 42, and the roller conveyor 48 may be disposed on the pedestal 45. The heated heating target 14 may be transported, for example, onto another conveyor 38 via the roller conveyor 48.

[0100] 12 , the irradiation chamber 36 may be portable. Microwaves may be irradiated from the microwave irradiator 3 to the heating target 14 inside the irradiation chamber 36, which is moving on a roller conveyor 31, and fluid generated from the heating target 14 may be discharged to the outside of the irradiation chamber 36 through an opening provided in the bottom surface of the irradiation chamber 36. A heat promoting member 140 containing a heat promoting agent may be fixed to the launcher of the microwave irradiator 3, and microwaves transmitted through the heat promoting member 140 may be irradiated onto the heating target 14. An electromagnetic wave shield 145 may be placed in the gap between the openable and closable portions of the irradiation chamber 36.

[0101] Although the present invention has been described above with reference to various embodiments, the descriptions and drawings that form part of this disclosure should not be understood to limit the present invention. Various alternative embodiments, examples, and operating techniques will become apparent to those skilled in the art from this disclosure. For example, components of the heating device shown in different drawings may be combined. Thus, it should be understood that the present invention encompasses various embodiments not described herein.

[0102] 1...stage, 2...microwave generating unit, 3...microwave irradiating unit, 4...non-contact thermometer, 5...window, 6...air curtain supply unit, 8...portion containing heating promoter, 9...opening, 11...pressing unit, 13...portion not containing heating promoter, 14...heating target, 15...drain pan, 17...drain pipe, 17a...valve, 18...rotating device, 19...caterpillar conveyor, 20...gas recovery pipe, 21...tank, 22...melting furnace, 24...suction pump, 25...liquefaction device 26...Camera, 27...Camera, 28...Liquid, 29...Molten metal, 30...Tray, 31...Roller conveyor, 32...Opening, 34...Loading stage, 36...Irradiation chamber, 38...Conveyor, 40...Movable stage, 41...Stopper, 42...Base, 43...Pressing portion, 45...Base, 48...Roller conveyor, 103...Microwave transparent window, 105...Recovery portion, 106...Liquid recovery portion, 107...Gas recovery portion, 111...Support portion, 113...Opening, 115... Loading hatch, 116: drive unit, 117: unloading hatch, 118: drive unit, 130: fan, 140: heating promotion member, 145: electromagnetic wave shield, 150: pipe, 155: analyzing device, 160: hopper, 165: screw, 166: feeder, 167: drive unit, 200: non-contact thermometer, 205: press machine, 210a: thermometer, 215: insulating layer, 220: heating promotion member, 225: reflector, 230: jig, 255: gas introduction pipe, 256... Gas inlet pipe, 257...gas inlet pipe, 260...gas exhaust pipe, 261...gas exhaust pipe, 262...gas exhaust pipe, 325...pushing part, 335...guide, 340...raw material, 400...pre-heating chamber, 401...post-heating chamber, 410A...inlet door, 410B...outlet door, 411...outlet door, 412...inlet, 413...outlet, 420...contact member, 425...holding member, 426...holding member, 430...shaft, 431...sleeve, 435...shaft, 440...rotary table

Claims

1. A heating device comprising: a microwave irradiation unit configured to irradiate a heating object with microwaves; and a recovery unit configured to recover a fluid generated from the heating object irradiated with the microwaves.

2. The heating device of claim 1, wherein the fluid is a liquid, and the recovery section includes a liquid recovery section configured to recover the liquid.

3. The heating device according to claim 2, wherein the liquid recovery section is disposed below the object to be heated in the direction of gravity.

4. The heating device according to claim 2, wherein the liquid recovery section includes a drain pan for receiving the liquid.

5. The heating device according to claim 4, wherein the liquid recovery section further includes a drain pipe connected to the drain pan and through which the liquid flows.

6. The heating device according to claim 5, wherein the liquid recovery section further includes a tank connected to the drain pipe for storing the liquid.

7. The heating device of claim 1, wherein the fluid is a gas, and the recovery section includes a gas recovery section configured to recover the gas.

8. The heating device according to claim 7, wherein the gas recovery section includes a gas recovery pipe connected to an irradiation chamber in which the object to be heated and irradiated with the microwaves is placed.

9. The heating device according to claim 7, wherein the gas recovery section includes a liquefaction device that liquefies the recovered gas.

10. The heating device according to claim 1, further comprising a holding member for holding the object to be heated, the holding member having an opening for allowing the fluid to pass through to the recovery section.

11. The heating device of claim 10, wherein the holding member rotates.

12. The heating device according to claim 10, wherein the holding member has a hollow shape and the object to be heated is placed inside the holding member.

13. The heating device according to claim 1, further comprising: an irradiation chamber in which the object to be heated and irradiated with the microwaves is placed; a pre-heating chamber connected to the irradiation chamber; and a gas environment adjusting device that makes the gas environment in the irradiation chamber the same as the gas environment in the pre-heating chamber, wherein the object to be heated is placed in the pre-heating chamber before being irradiated with the microwaves.

14. The heating device according to claim 1, further comprising: an irradiation chamber in which the object to be heated and irradiated with the microwaves is placed; a post-heating chamber connected to the irradiation chamber; and a gas environment adjusting device that makes the gas environment in the irradiation chamber the same as the gas environment in the post-heating chamber, wherein the object to be heated after being irradiated with the microwaves is placed in the post-heating chamber.

15. The heating device of claim 1, wherein the fluid is at least one of oil and water.

Images