CN113758266A

CN113758266A - Degreasing furnace and degreasing method

Info

Publication number: CN113758266A
Application number: CN202110562879.9A
Authority: CN
Inventors: 寒川喜光; 田中优; 吉冈尚规
Original assignee: Molaji Co ltd; Shimadzu Corp
Current assignee: Molaji Co ltd; Shimadzu Corp
Priority date: 2020-06-05
Filing date: 2021-05-24
Publication date: 2021-12-07
Also published as: KR20210151691A

Abstract

The invention provides a degreasing furnace and a degreasing method, which can perform degreasing treatment in a short time. The degreasing furnace (10) comprises: a furnace body (14) that houses a degreased object (12) containing ceramic; a gas source (16) for supplying an inert gas to the furnace body (14); a heating device for heating the inert gas; a saturated vapor generation device (18) that generates saturated vapor or a liquid source (48) of liquid; and a superheater (20) that generates superheated steam from the liquid or saturated steam after supplying an inert gas to the furnace body (14), and supplies the superheated steam to the furnace body (14).

Description

Degreasing furnace and degreasing method

Technical Field

The invention relates to a degreasing furnace and a degreasing method.

Background

Conventionally, a degreased object including ceramics is degreased in a degreasing furnace. For example, the furnace of patent document 1 includes: a furnace body for containing the degreased object and a heating device for heating the degreased object. The furnace of patent document 1 heats the degreasing gas to remove the organic matter decomposition gas. A part of the degreasing gas from which the organic matter decomposition gas is removed is introduced into the furnace body again. Patent document 1 describes that the oxygen concentration is kept low to prevent cracking of the degreased material.

[ Prior art documents ]

[ patent document ]

[ patent document 1] International publication No. WO2005/047207

Disclosure of Invention

[ problems to be solved by the invention ]

When degreasing is performed by introducing nitrogen or the like into the furnace main body, it takes time to raise the temperature of the ceramics because the heating element is provided in the furnace wall. The furnace of patent document 1 may take a long time to degrease.

Accordingly, an object of the present invention is to provide a degreasing furnace and a degreasing method capable of performing a degreasing treatment in a short time.

[ means for solving problems ]

In order to solve the above problems, the degreasing furnace of the present invention includes the following configuration.

The degreasing furnace of the present invention is a degreasing furnace for degreasing a degreased object including ceramics, and includes: a furnace body for accommodating the degreased object; a first gas source of a first gas, the first gas being an inert gas supplied to the furnace body; a heating device for heating the first gas; a saturated vapor generating device that generates saturated vapor or a liquid source of liquid; a superheater that generates superheated steam from the liquid or the saturated steam and supplies the superheated steam to the furnace main body; and a control device for controlling the furnace body to be supplied with superheated steam from the superheater after the temperature of the degreased matter is raised by supplying the first gas to the furnace body. In addition, a second gas source of the second gas, which is the atmosphere supplied to the furnace body in place of the first gas source, may be included. Further, both a first gas source and a second gas source may also be included.

The degreasing method of the invention comprises the following steps: a step of receiving a degreased object containing ceramic in a furnace body; a step of raising the temperature of an inert gas as a first gas source; a step of supplying the heated first gas into a furnace body; introducing the first gas into the furnace body to raise the temperature of the degreased object in advance; a step of generating superheated steam from saturated steam or liquid in the superheater; supplying the superheated steam to a furnace body; and a step of finishing degreasing the degreased object by using the superheated steam. Instead of the first gas source, the atmosphere as the second gas may be heated and supplied to the furnace main body. Further, both of the first gas and the second gas may be supplied to the furnace main body.

[ Effect of the invention ]

According to the present invention, since the superheated steam is used, the heat capacity is large and the heat conduction is high, the temperature of the degreased object is easily raised. Degreasing is completed in a short time. Further, before degreasing the object to be treated with the superheated steam, the temperature of the object to be treated is raised with the inert gas. The superheated steam can be prevented from condensing or becoming saturated steam and contacting the object to be treated. The reaction caused by the treated material and water is hard to occur, and the deterioration of the treated material can be suppressed.

Drawings

Fig. 1 is a view showing the structure of a degreasing furnace according to the present invention.

Fig. 2 is a graph showing the ambient temperature of the furnace main body.

FIG. 3 is a view showing the structure of another degreasing furnace according to the present invention.

FIG. 4 is a view showing the structure of another degreasing furnace according to the present invention.

Fig. 5 is a diagram showing the structure of the degreasing furnace including the second gas source.

Fig. 6 is a diagram showing the structure of a degreasing furnace including a first gas source and a second gas source.

Fig. 7 is a graph showing the ambient temperature of the furnace main body.

Fig. 8 is a view showing the structure of another degreasing furnace including a first gas source and a second gas source.

Fig. 9 is a view showing the structure of another degreasing furnace including a first gas source and a second gas source.

Description of the symbols

10. 46, 50, 54, 60, 62, 64: degreasing furnace

12: defatted material

14: furnace body

16: a first gas source

18: saturated steam generating device

20: superheater

22: inner space of furnace body

24: support frame

26: supply port

28: exhaust port

30. 32, 34, 58: piping

36: temperature meter

38: control device

40: waste gas combustion furnace

42: heat insulator

44: exhaust passage

48: liquid source

52: heating device

56: second gas source

Detailed Description

The degreasing furnace and the degreasing method of the present invention will be described with reference to the drawings. Although a plurality of embodiments are described, the same elements may be denoted by the same reference numerals and the description thereof may be omitted even in different embodiments.

[ embodiment 1]

The degreasing furnace 10 of the present application shown in fig. 1 includes: a furnace body 14 for containing the degreased objects 12, a first gas source 16 of inert gas, a saturated steam generating device 18 of saturated steam, and a superheater 20 for generating superheated steam.

[ defatted Material ]

The degreased object 12 includes a ceramic compact. The ceramic comprises: nitride-based ceramics (aluminum nitride, silicon nitride, etc.), carbide-based ceramics (silicon carbide, boron carbide, etc.), and oxide-based ceramics (aluminum oxide, zirconium, etc.), and the present embodiment particularly includes nitride-based ceramics. The degreased material 12 contains a binder. The binder is mixed in the ceramic when the degreased object 12 is formed. When the temperature of the degreased object 12 is raised, the binder is released from the degreased object 12 as a gas. As the binder, polybutylmethacrylate, polyvinyl alcohol, methyl cellulose, vinyl acetate, polyethylene glycol, and the like are used as resins, and a lubricant, a plasticizer, and a dispersant are used.

[ furnace body ]

The furnace body 14 includes a heat-resistant material such as SUS310S or SUS 316L. The furnace main body 14 is formed in a container shape, and stores the degreased objects 12 in an internal space 22 thereof. A door is provided at an arbitrary position of the furnace main body 14, and the door is opened and closed when the degreased material 12 is taken in and out. A holder 24 for holding the degreased object 12 may be included in the inner space 22 of the furnace body 14. The furnace main body 14 is formed with a supply port 26 and an exhaust port 28. The inert gas and the superheated steam are supplied from the supply port 26 to the internal space 22 of the furnace main body 14. Gas generated when the degreased object 12 is degreased is discharged from the gas outlet 28.

[ first gas Source ]

The first gas source 16 is a device that stores, generates, or both of an inert gas (first gas). The inert gas is nitrogen, argon, helium, neon, etc. The heated inert gas is supplied to the furnace body 14. The superheater 20 functions as a heating device for the inert gas, and does not include a special heating device for raising the temperature of the inert gas. The gas flow rate of the first gas source 16 is preferably 250L/min or more, and more preferably 300L/min or more. In this case, the temperature increase rate is increased, the heating efficiency in the superheater 20 is optimized, and the time for heating the degreased object 12 before the degreasing step is shortened or uniform heating is realized.

[ saturated vapor Generator ]

Includes a saturated steam generating device 18 that supplies saturated steam to a superheater 20. The saturated vapor generator 18 includes a boiler that boils a liquid such as pure water to generate saturated vapor.

[ superheater ]

The superheater 20 is a device for generating superheated steam from saturated steam. Examples of the superheater 20 include: convection superheater, radiation superheater, suspension superheater, platen superheater, horizontal superheater, etc. The superheater 20 comprises a long tube through which saturated steam flows. The saturated steam flowing through the long tube is heated to become superheated steam. The generated superheated steam is supplied to the furnace body 14. The superheated steam contains colorless transparent water (H) at normal pressure and 100 deg.C to higher temperature₂O) gas. The temperature of the superheated steam is 500 ℃ or higher, preferably 600 to 1200 ℃.

As described above, the superheater 20 also functions as a heating device for the inert gas. The inert gas is supplied to the superheater 20 to raise the temperature. The inert gas is heated to 130 ℃ or higher, preferably 150 to 300 ℃. The heated inert gas is supplied to the furnace body 14.

[ piping ]

The furnace main body 14 and the superheater 20 are connected by a first pipe 30. The heated inert gas and superheated steam are supplied from the superheater 20 to the furnace main body 14 through the first pipe 30. Since the high-temperature inert gas and the superheated steam flow through the first pipe 30, the first pipe 30 preferably includes a heat-resistant material. The second pipe 32 is attached to the first gas source 16, and the third pipe 34 is attached to the saturated vapor generating device 18. The second pipe 32 merges with the third pipe 34 and is connected to the superheater 20. Valves may be attached to the

pipes

32 and 34, and the flow rates of the inert gas, the saturated steam, and the superheated steam may be controlled by opening and closing the valves.

[ thermometer ]

The present application includes a thermometer 36 to measure the ambient temperature of the interior space 22 of the furnace body 14. The thermometer 36 utilizes a thermocouple thermometer. The supply of the inert gas and the superheated steam into the furnace main body 14 is controlled based on the measured temperature. Accordingly, the present application includes a control device 38 for controlling the first gas source 16, the superheater 20, and the saturated vapor generating device 18.

[ control device ]

The control device 38 includes an arithmetic device such as a Central Processing Unit (CPU) or a Programmable Logic Controller (PLC). The controller 38 controls the first gas source 16, the superheater 20, and/or the saturated steam generator 18 so that the ambient temperature of the internal space 22 of the furnace main body 14 reaches a predetermined temperature. In the present application, the temperature of the degreased objects 12 is raised in advance by supplying the inert gas to the furnace main body 14 under the control of the controller 38. Then, superheated steam is supplied from the superheater 20 to the furnace main body 14, and the degreased matter 12 is degreased.

[ exhaust gas combustion furnace ]

An exhaust gas burner 40 is connected to the exhaust port 28 of the furnace body 14. The exhaust gas combustion furnace 40 includes an exhaust gas duct 44 formed by a heat insulator 42 and a heating device (not shown). The heating device is as follows: electric heaters, gas burners, or oil burners, etc. The gas released from degreased matter 12 passes through exhaust passage 44. The heating device heats the gas, and decomposes or converts the gas into a gas such as carbon dioxide.

Also included in the interior space 22 of the furnace body 14 are: a fan (not shown) for sucking the inert gas and the superheated steam, and a fan (not shown) for exhausting the gas generated by degreasing from the internal space 22 of the furnace main body 14.

[ degreasing method ]

Next, a degreasing method using the degreasing furnace 10 will be described. (1) The degreased material 12 is accommodated in the internal space 22 of the furnace body 14. For example, the degreased object 12 is a formed article including a nitride-based ceramic.

(2) Inert gas is supplied from a first gas source 16 to a superheater 20. For example, the inert gas is nitrogen. The superheater 20 heats the inert gas and supplies the inert gas to the furnace main body 14. The ambient temperature of the furnace main body 14 rises (time T0 to time T1 in fig. 2), and the degreased matter 12 stored in the furnace main body 14 rises in temperature. In this temperature raising step, the ambient temperature of the internal space 22 of the furnace main body 14 is raised to 130 ℃ or higher, preferably 150 to 300 ℃, by using, for example, an inert gas, at a temperature at which condensation does not occur due to the temperature difference between the degreased matter 12 and the superheated steam.

(3) As shown in time T1 to T2 of fig. 2, the inert gas having a high temperature is supplied to the furnace main body 14 so as to maintain the ambient temperature of the furnace main body 14. The surface and internal temperature of the degreased objects 12 are also raised to a predetermined temperature. The degreased object 12 is also heated before the degreasing step by raising the temperature with the inert gas. It has been known that the degreased matter 12 is easily affected by moisture. However, since superheated steam is a high-temperature gas, no water in a liquid state is present, and it is considered that even if the object to be degreased 12 which is easily affected by water is used, the object to be degreased can be degreased by superheated steam. However, as a result of intensive studies by the inventors of the present application, it has been found that, in the conventional technique without a preliminary heating step as in the present application, when the object to be degreased 12 in a normal temperature state is exposed to the superheated steam, condensation occurs in the object to be degreased 12 due to a temperature difference between the object to be degreased 12 and the superheated steam, and the degreasing result is deteriorated. In the present invention, by heating the degreased object 12 in advance before the degreasing step, even if the degreased object 12 is of a type that is easily affected by water, high degreasing performance can be achieved by using superheated steam. In addition, degreasing may also be started in a stage of the heating step in advance.

(4) The temperature of the object to be degreased 12 is raised in advance by the inert gas, and then the object to be degreased 12 is degreased by the superheated steam. Thus, the supply of inert gas from the first gas source 16 to the superheater 20 is stopped. The saturated vapor generation device 18 heats the liquid to generate saturated vapor, and supplies the saturated vapor to the superheater 20. The superheater 20 generates superheated steam from the saturated steam. The superheated steam is supplied to the furnace body 14.

The ambient temperature of the internal space 22 of the furnace body 14 is increased by the superheated steam (time T2 to time T3 in fig. 2). The ambient temperature of the internal space 22 of the furnace main body 14 at this time is higher than the ambient temperature when the inert gas is supplied. For example, the ambient temperature is raised to 500 ℃ or higher, preferably 600 to 1200 ℃. The degreased object 12 is degreased in a state where the ambient temperature of the furnace main body 14 is increased (time T3 to T4 of fig. 2). The degreased object 12 is degreased with superheated steam.

The degreasing method utilizes superheated steam to degrease after heating by using inert gas. The degreased matter 12 is heated by an inert gas before being degreased by superheated steam. When the object to be degreased 12 is at a low temperature without preheating, if the superheated steam contacts the object to be degreased 12, the superheated steam is cooled and condensed or becomes saturated steam. When the water droplets contact the degreased object 12, the degreased object 12 reacts with water and deteriorates. Since the object to be degreased 12 is heated by the inert gas, condensation of the superheated steam can be prevented, and the object to be degreased 12 can be prevented from reacting with water. In particular, when the object to be degreased 12 is a nitride-based ceramic, the object to be degreased 12 can be suppressed from being hydrolyzed, and deterioration of the object to be degreased 12 can be suppressed. For example, aluminum nitride becomes aluminum hydroxide and ammonia when hydrolyzed, but the present application can suppress such hydrolysis. Since the superheated steam has a large heat capacity and a high thermal conductivity, the degreased object 12 can be heated and degreased in a short time. Further, if the binder of the degreased object 12 contains a water-soluble binder such as methylcellulose or polyvinyl alcohol, the degreased object 12 may be deteriorated by moisture, but since condensation can be prevented as described above, deterioration of the degreased object 12 can be prevented.

Gas generated when the object to be degreased 12 is degreased is supplied from the exhaust port 28 to the exhaust gas burner 40, and is burned into carbon dioxide or the like and discharged.

(5) When the degreasing of the object 12 by the superheated steam is completed, the generation and supply of the superheated steam are stopped. The ambient temperature of the internal space 22 of the furnace main body 14 decreases (time T4 to time T5 in fig. 2), and the temperature of the degreased objects 12 also decreases. When the temperature of the degreased objects 12 is lowered, the degreased objects 12 are taken out from the furnace body 14. Then, the degreased object 12 may be added to a sintering furnace for sintering.

The graph of fig. 2 differs depending on the shape and size of the furnace main body 14, the amount of inert gas supplied to the furnace main body 14 per unit time, and the amount of superheated steam supplied to the furnace main body 14 per unit time.

As described above, the present invention can suppress hydrolysis of the defatted material 12 and can prevent degradation of the defatted material 12. In the case of degreasing with an inert gas, it takes time to degrease the object to be degreased 12, but in the present invention, since the object to be degreased 12 is heated with an inert gas and thereafter is degreased with superheated steam, the time for degreasing can be set to a short time.

[ embodiment 2]

A liquid such as pure water may also be supplied to the superheater 20. As in the degreasing furnace 46 shown in fig. 3, the superheater 20 is connected to a liquid source 48 by a third pipe 34. The liquid source 48 includes a device that generates liquid, a reservoir that stores liquid, or both. The liquid is supplied from the liquid source 48 to the superheater 20, and the superheater 20 heats the liquid to generate superheated steam. The temperature of the liquid supplied to the superheater 20 is not limited. In this case, the first gas source 16 and the superheater 20 are connected by the second pipe 32, and the inert gas is supplied from the first gas source 16 to the superheater 20 through the second pipe 32. The inert gas is heated in the superheater 20 and supplied to the furnace main body 14.

[ embodiment 3]

As in the degreasing furnace 50 shown in fig. 4, a heating device 52 for raising the temperature of the inert gas may be provided. The heating device 52 is located midway in the second pipe 32. A second pipe 32 connects the furnace body 14 to the first gas source 16. The inert gas from the first gas source 16 is heated in the heating device 52 and then supplied to the furnace body 14. The first pipe 30 and the second pipe 32 may be connected to the furnace main body 14 separately, or may be connected to the furnace main body 14 by merging into one.

The heating device 52 may be integral with the first gas source 16. The temperature of the inert gas is raised in the first gas source 16, and the inert gas is supplied to the furnace main body 14 through the second pipe 32.

[ embodiment 4]

A heating device 52 for heating the inert gas may also be located in the interior space 22 of the furnace body 14. The inert gas is supplied from the first gas source 16 to the furnace body 14 without being heated up, and is heated up in the internal space 22 of the furnace body 14.

[ embodiment 5]

The degreasing furnace 54 of fig. 5 includes a second gas source 56 in place of the first gas source 16. The other structure is the same as the degreasing furnace 10 of fig. 1. The second gas source 56 is a gas source for supplying a gas (second gas) other than an inert gas, such as compressed air. The compressed gas may be, regardless of the kind, an atmosphere containing nitrogen, oxygen, argon, and carbon dioxide as main components. Since the atmosphere is used and no special gas is used, the versatility of the degreasing furnace 54 is high. The second gas may also be dry air having a dew point temperature of-15 ℃ or less. This is because the second gas does not condense the degreased matter 12. It is preferable to remove fine dust, oil, and the like from the second gas. Second gas source 56 may also include a compressor to compress the gas. The pressure of the second gas is about 1Mpa or less. The second gas source 56 and the superheater 20 are connected by a fourth piping 58. The fourth pipe 58 may include a valve for adjusting the flow rate of the second gas. The flow rate of the second gas supplied to the furnace main body 14 is preferably 250L/min or more, and more preferably 300L/min or more. This is because the temperature of the degreased matter 12 is raised in a short time, as in the first gas of the above embodiment.

The object 12 to be degreased in the degreasing furnace 54 in fig. 5 is preferably a ceramic other than a nitride-based ceramic. For example, the object 12 to be degreased in the degreasing furnace 54 may be oxide ceramics such as alumina or zirconium. The binder contained in the degreased material 12 is preferably a water-soluble binder that is not affected by moisture, such as methylcellulose. This is because the degreased object 12 is not deteriorated when the temperature of the degreased object 12 is raised by the second gas.

Similarly to embodiment 1, the second gas of the second gas source 56 is heated in the superheater 20 and supplied to the furnace main body 14. The temperature of the degreased objects 12 is raised by the second gas before supplying the superheated steam to the furnace main body 14.

In the degreasing furnace 46 of fig. 3 and the degreasing furnace 50 of fig. 4, the first gas source 16 may be replaced with a second gas source 56. In the degreasing furnace 46 and the degreasing furnace 50, the temperature of the object to be degreased 12 may be increased by the second gas instead of the first gas before degreasing.

By using the second gas (atmosphere) instead of the first gas (inert gas), the cost of the gas used for preliminary heating before degreasing can be suppressed. The cost for degreasing can be suppressed, and the price of the degreased object 12 can be suppressed.

[ embodiment 6]

The gas sources of the degreasing furnace 60 of fig. 6 include both the first gas source 16 and the second gas source 56. One end of the fourth pipe 58 is connected to the second gas source 56, and the other end of the fourth pipe 58 is connected to the second pipe 32 or the superheater 20. The other structure is the same as the degreasing furnace 10 of fig. 1.

The control device 38 controls the valves attached to the first gas source 16, the second gas source, the saturated steam generating device 18, the superheater 20, and the

pipes

32, 34, and 58 so that the second gas, the first gas, and the superheated steam are supplied to the furnace main body 14 in this order. The temperature of the degreased object 12 is raised by the second gas before the first gas is supplied to the furnace main body 14. For example, the second gas is supplied to the furnace body 14 from time T0 in fig. 7. After the prescribed temperature is reached at time T1', the temperature of the furnace body 14 is maintained from time T1' to time T1 '. When the time T1 ″ is reached, the first gas is supplied to the furnace main body 14. In addition, the time from the time T1' to the time T1 ″ is arbitrary. The temperature of the first gas is higher than the temperature of the second gas, and the temperature of the saturated vapor is higher than the temperature of the first gas.

The temperature of the second gas is a temperature at which condensation, oxidation, or both of condensation and oxidation do not occur in the degreased objects 12 when the first gas is supplied to the furnace main body 14. For example, the second gas is formed by compressing atmospheric air or the like, and there is a possibility that the object to be degreased 12 is deteriorated by moisture, oxygen, or both of them due to condensation. The temperature of the second gas is set in such a way that no condensation, no oxidation or both occurs. The second gas is less expensive than the first gas, and the temperature of the object to be degreased 12 can be raised by using the second gas, so that the amount of the first gas used can be reduced, and the cost for degreasing the object to be degreased 12 can be reduced. The temperature at which the object to be degreased 12 is heated by the second gas is appropriately selected according to the kind of the object to be degreased 12, the content of the degreased, and the like, so that the object to be degreased 12 is not deteriorated. For example, the temperature of the second gas is about 100 ℃ to 250 ℃.

[ embodiment 7]

The degreasing furnace 62 of fig. 8 includes both the first gas source 16 and the second gas source 56. The other structure of the degreasing furnace 62 is the same as the degreasing furnace 46 of fig. 3. Before the first gas is supplied to the furnace body 14, the second gas is heated in the superheater 20 and supplied to the furnace body 14. Similarly to embodiment 6, the temperature of the object to be degreased 12 is raised by the second gas under the control of the controller 38, then the temperature of the object to be degreased 12 is raised by the first gas, and finally the object to be degreased 12 is degreased by the superheated steam.

[ embodiment 8]

The degreasing furnace 64 of fig. 9 includes both the first gas source 16 and the second gas source 56. The other structure of the degreasing furnace 64 is the same as the degreasing furnace 50 of fig. 4. Before the first gas is supplied to the furnace main body 14, the second gas is heated in the heating device 52 and supplied to the furnace main body 14. Similarly to embodiment 6, the temperature of the object to be degreased 12 is raised by the second gas under the control of the controller 38, then the temperature of the object to be degreased 12 is raised by the first gas, and finally the object to be degreased 12 is degreased by the superheated steam. The heating device 52 of the degreasing furnace 64 is one, and the heating device 52 may be included for each of the first gas source 16 and the second gas source.

[ embodiment 9]

Embodiments 6 to 8 include the first gas source 16 and the second gas source 56, but the degreasing described in embodiments 1 to 5 may be performed using only one of the

gas sources

16 and 56.

A degreasing furnace according to an embodiment (1) is a degreasing furnace for degreasing a degreased object including ceramics, and includes: a furnace body for accommodating the degreased object; a first gas source of a first gas, the first gas being an inert gas supplied to the furnace body; a heating device for heating the first gas; a saturated vapor generating device that generates saturated vapor or a liquid source of liquid; a superheater that generates superheated steam from the liquid or the saturated steam and supplies the superheated steam to the furnace main body; and a control device for supplying the first gas to the furnace body to raise the temperature of the degreased object, and then controlling the supply of superheated steam from the superheater to the furnace body.

The degreasing furnace according to item 1, wherein the temperature of the degreased object is raised by an inert gas, and then the degreased object is degreased by superheated steam. The superheated steam is cooled to condense or turn into saturated steam, and the contact of water droplets with the degreased matter can be suppressed. Can prevent degreased substance from hydrolysis and deterioration. By using superheated steam, the degreasing time can be shortened.

A degreasing furnace according to an embodiment (2) is a degreasing furnace for degreasing a degreased object including ceramics, and includes: a furnace body for accommodating the degreased object; a second gas source of a second gas, the second gas being atmospheric air supplied to the furnace body; a heating device for heating the second gas; a saturated vapor generating device that generates saturated vapor or a liquid source of liquid; a superheater that generates superheated steam from the liquid or the saturated steam and supplies the superheated steam to the furnace main body; and a control device for controlling the supply of the superheated steam from the superheater to the furnace body after the temperature of the degreased matter is raised by supplying the second gas to the furnace body.

The degreasing furnace according to item 2, wherein the temperature of the degreased object is raised by the atmosphere, and then the degreased object is degreased by the superheated steam. The temperature of the degreased matter can be raised at a low price.

A degreasing furnace according to an embodiment (3) is a degreasing furnace for degreasing a degreased object including ceramics, and includes: a furnace body for accommodating the degreased object; a first gas source of a first gas, the first gas being an inert gas supplied to the furnace body; a second gas source of a second gas, the second gas being atmospheric air supplied to the furnace body; a heating device for heating the first gas and the second gas; a saturated vapor generating device that generates saturated vapor or a liquid source of liquid; a superheater that generates superheated steam from the liquid or the saturated steam and supplies the superheated steam to the furnace main body; and a control device for controlling the supply of the superheated steam from the superheater to the furnace main body after the temperature of the degreased matter is raised by supplying the second gas and the first gas to the furnace main body.

The degreasing furnace according to item 3, wherein the temperature of the degreased object is raised using air and an inert gas, and then the degreased object is degreased using superheated steam. By using the atmosphere, the amount of the inert gas used is reduced, and the manufacturing cost can be suppressed.

(item 4) the control device controls the first gas source and the second gas source so that the second gas is supplied to the furnace main body and then the first gas is supplied.

The degreasing furnace as set forth in claim 4, wherein the temperature of the degreased object is raised by the second gas in advance, and then the temperature of the degreased object is raised by the first gas. The second gas can be used to make the degreased object difficult to deteriorate.

(item 5) the heating means comprises a superheater.

The degreasing furnace according to item 5, wherein a superheater is used to raise the temperature of the inert gas or the atmosphere, and a special heating device is not used because the superheater is an inert gas or an atmosphere.

(item 6) the temperature of the superheated steam supplied to the furnace main body is higher than the temperatures of the first gas and the second gas.

The degreasing furnace according to item 6, wherein the temperature of the degreased object is raised by the first gas and the second gas, and then the degreased object is degreased by the superheated steam.

(item 7) the degreased object includes a nitride-based ceramic.

The degreasing furnace according to claim 7 can suppress hydrolysis as described above, and thus the present invention is suitable for degreasing nitride-based ceramics.

(item 8) the defatted substance contains a water-soluble binder.

The degreasing furnace according to item 8, wherein deterioration of the degreased object due to moisture can be suppressed by using an inert gas or using the atmosphere for suppressing condensation.

(item 9) is characterized in that the first gas source and the second gas source are supplied with the first gas and the second gas at 300L/min or more.

The degreasing furnace according to claim 9, wherein the temperature of the degreased object is increased and uniformly increased by supplying the first gas and the second gas to the furnace main body at a rate of 300L/min or more.

The method of degreasing according to the first aspect of the invention (item 10) comprises: a step of receiving a degreased object containing ceramic in a furnace body; a step of raising the temperature of an inert gas as a first gas source; a step of supplying the heated first gas into a furnace body; introducing the first gas into the furnace body to raise the temperature of the degreased object in advance; a step of generating superheated steam from saturated steam or liquid in the superheater; supplying the superheated steam to a furnace body; and a step of finishing degreasing the degreased object by using the superheated steam.

The degreasing method as described in item 10, wherein the temperature of the degreased object is raised by an inert gas, and then the degreased object is degreased by superheated steam. The superheated steam is cooled to condense or turn into saturated steam, and the water droplets can be prevented from contacting the degreased matter and hydrolyzing the degreased matter. By using superheated steam, the degreasing time can be shortened.

The method of degreasing as described in (11) above, comprising: a step of receiving a degreased object containing ceramic in a furnace body; a step of raising the temperature of the atmosphere of the second gas as the second gas source; a step of supplying the heated second gas into a furnace body; introducing the second gas into the furnace body to raise the temperature of the degreased object in advance; a step of generating superheated steam from saturated steam or liquid in the superheater; supplying the superheated steam to a furnace body; and a step of finishing degreasing the degreased object by using the superheated steam.

The degreasing method as described in claim 11, wherein the temperature of the degreased object is raised by the atmosphere, and then the degreased object is degreased by the superheated steam. The temperature of the degreased matter can be raised at a low price.

The method of degreasing as described in (item 12) above, comprising: a step of receiving a degreased object containing ceramic in a furnace body; a step of raising the temperature of the atmosphere of the second gas as the second gas source; a step of supplying the heated second gas into a furnace body; introducing the second gas into the furnace body to raise the temperature of the degreased object in advance; a step of raising the temperature of an inert gas as a first gas source; a step of supplying the heated first gas into a furnace body; introducing the first gas into the furnace body to raise the temperature of the degreased object in advance; a step of generating superheated steam from saturated steam or liquid in a superheater; supplying the superheated steam to a furnace body; and a step of finishing degreasing the degreased object by using the superheated steam.

The degreasing method as described in claim 12, wherein the temperature of the degreased object is raised using an atmosphere and an inert gas, and then the degreased object is degreased using superheated steam. By using the atmosphere, the amount of the inert gas used is reduced, and the manufacturing cost can be suppressed.

(item 13) before introducing the first gas into the furnace body, the second gas is introduced into the furnace body to raise the temperature of the degreased object in advance.

The degreasing method as described in item 13, wherein the temperature of the degreased object is raised by the second gas in advance, and then the temperature of the degreased object is raised by the first gas. The second gas can be used to prevent the degreased objects from deteriorating.

(item 14) the first gas and the second gas are warmed in a superheater.

The degreasing method as set forth in claim 14, wherein a heating device is not separately provided for raising the temperature of the first gas and the second gas.

(item 15) the superheated vapor has a temperature higher than the temperatures of the first gas and the second gas.

The degreasing method as described in claim 15, wherein the temperature of the degreased object is raised by the first gas and the second gas, and the degreased object is degreased by the superheated steam.

(item 16) the degreased material includes a nitride-based ceramic.

The degreasing method according to claim 16 can suppress hydrolysis of a degreased object as described above, and is therefore suitable for a nitride-based ceramic.

(item 17) the defatted substance contains a water-soluble binder.

The degreasing method as described in item 17, wherein deterioration of the degreased object due to moisture can be suppressed by using an inert gas or using the atmosphere for suppressing condensation.

(item 18) is characterized in that the first gas source and the second gas source are supplied with the first gas and the second gas at 300L/min or more.

The degreasing method as described in item 18, wherein the temperature of the degreased object is increased and uniformly increased by supplying the first gas and the second gas to the furnace main body at a rate of 300L/min or more.

In addition, the present invention can be implemented in various forms of improvement, modification, and alteration based on knowledge of those skilled in the art without departing from the scope of the present invention. The embodiments described are not independent, and can be implemented by being appropriately combined based on the knowledge of those skilled in the art.

Claims

1. A degreasing furnace for degreasing a degreased object containing ceramics, wherein the degreasing furnace comprises:

a furnace body for accommodating the degreased object;

a gas source for supplying gas to the furnace body;

a heating device for heating the gas;

a saturated vapor generating device that generates saturated vapor or a liquid source of liquid;

a superheater that generates superheated steam from the liquid or the saturated steam and supplies the superheated steam to the furnace main body; and

and a control device for controlling the gas to be supplied to the furnace main body to raise the temperature of the degreased object, and then supplying superheated steam from the superheater to the furnace main body.

2. The degreasing furnace of claim 1, wherein the gas source supplies a first gas to the furnace body, the first gas being an inert gas.

3. The degreasing furnace of claim 1, wherein the gas source supplies a second gas to the furnace body, the second gas being atmospheric air.

4. The degreasing furnace of claim 1, wherein

The gas source includes a first gas source supplying a first gas to the furnace body, the first gas being an inert gas, and a second gas source supplying a second gas to the furnace body, the second gas being atmospheric air.

5. The degreasing furnace of claim 4, wherein

The control device controls the first gas source and the second gas source in a manner that the second gas is supplied to the furnace body and then the first gas is supplied.

6. The degreasing furnace of claim 1, wherein

The heating device comprises a superheater.

7. The degreasing furnace of claim 1, wherein

The superheated steam is supplied to the furnace body at a temperature higher than that of the gas.

8. The degreasing furnace of claim 1, wherein

The degreased object contains nitride ceramics.

9. The degreasing furnace of claim 1, wherein

The degreased matter comprises a water-soluble binder.

10. The degreasing furnace of claim 1, wherein

The gas source supplies the gas at 300L/min or more.

11. A degreasing method, comprising:

a step of receiving a degreased object containing ceramic in a furnace body;

a step of heating the gas supplied from the gas source;

a step of supplying the heated gas into a furnace body;

introducing the gas into a furnace body to raise the temperature of the degreased object in advance;

a step of generating superheated steam from saturated steam or liquid in the superheater;

supplying the superheated steam to a furnace body; and

and a step of finishing degreasing the degreased object by using the superheated steam.

12. Degreasing method according to claim 11, wherein the gas supplied by the gas source is an inert gas.

13. Degreasing method according to claim 11, wherein the gas supplied by the gas source is atmospheric air.

14. The degreasing method of claim 11, wherein the gas supplied by the gas source is an inert gas and atmospheric air.

15. Degreasing method according to claim 14, wherein

Before introducing the inert gas into the furnace body, the atmosphere is introduced into the furnace body to raise the temperature of the degreased object in advance.

16. Degreasing method according to claim 11, wherein

The gas is warmed using a superheater.

17. Degreasing method according to claim 11, wherein

The superheated vapor is at a temperature higher than the temperature of the gas.

18. Degreasing method according to claim 11, wherein

The degreased object contains nitride ceramics.

19. Degreasing method according to claim 11, wherein

The degreased matter comprises a water-soluble binder.

20. Degreasing method according to claim 11, wherein

The gas source supplies the gas at 300L/min or more.