KR20220136115A - Heat treatment system - Google Patents

Abstract

The present invention is to reduce components, which are produced by heat treatment and adversely affect the heat treatment while reducing gas consumption. A heat treatment system (10) includes: a heat treatment furnace (1) for performing heat treatment; a reaction unit (2) for allowing a first component included in a gas after heat treatment, produced by the heat treatment in the heat treatment furnace (1), to react with a second component included in a reactive gas, so as to obtain a regeneration gas in which the first component is reduced; a reactive gas supply unit (3) for supplying the reactive gas to the reaction unit (2); and a circulation path (4) for introducing the gas after heat treatment to the reaction unit (2) and introducing the regeneration gas obtained by the reaction unit (2) to the heat treatment furnace (1).

Description

Heat treatment system {HEAT TREATMENT SYSTEM}

The present invention relates to a heat treatment system.

Conventionally, a heat treatment system for performing heat treatment on an object to be treated is known.

As one of such heat treatment systems, Patent Document 1 discloses a heat treatment system for controlling the flow rate of hydrogen supplied into the heat treatment furnace based on the oxygen concentration in the heat treatment furnace detected by the oxygen sensor and the target value of the oxygen concentration, have. In this heat treatment system, the gas in the heat treatment furnace is discharged through an exhaust pipe by the pressure in the heat treatment furnace.

However, in the heat treatment system described in Patent Literature 1, gas is supplied into the heat treatment furnace from the gas supply unit while heat treatment is performed on the object to be treated, and unnecessary gas is discharged from the exhaust pipe, so that the consumption of gas increases.

On the other hand, Patent Document 2 discloses a heat treatment system that reduces gas consumption by introducing a part of the gas in the heat treatment furnace into the circulation furnace to remove suspended dust in the gas, and then returning it to the heat treatment furnace.

Japanese Patent Laid-Open No. 2016-001064 Japanese Patent Laid-Open No. Hei 01-184390

However, in the heat treatment furnace, there are cases in which a substance having a bad influence on the heat treatment is generated by the heat treatment. For this reason, as in the heat treatment system described in Patent Document 2, in a configuration in which a part of the gas in the heat treatment furnace is introduced into the circulation furnace and returned to the heat treatment furnace again, substances of components that adversely affect the heat treatment continue to increase in the heat treatment furnace , there is a possibility that it may become difficult to perform a desired heat treatment on the object to be treated.

The present invention solves the above problems, and an object of the present invention is to provide a heat treatment system capable of reducing components that adversely affect heat treatment while reducing gas consumption.

The heat treatment system of the present invention

a heat treatment furnace for performing heat treatment;

a reaction unit for obtaining a regenerated gas in which the first component is reduced by reacting a first component included in the gas after heat treatment generated by the heat treatment in the heat treatment furnace and a second component included in the reaction gas;

a reaction gas supply unit for supplying the reaction gas to the reaction unit;

and a circulation path for introducing the gas after the heat treatment into the reaction unit and introducing the regeneration gas obtained from the reaction unit into the heat treatment furnace.

According to the heat treatment system of the present invention, the first component is reduced by supplying a reaction gas to the reaction unit and reacting the first component included in the gas after heat treatment generated by the heat treatment and the second component included in the reaction gas. get regeneration gas. By returning the obtained regenerated gas to the heat treatment furnace, the first component that adversely affects the heat treatment can be reduced while reducing the gas consumption.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows typically the structure of the heat processing system in 1st Embodiment of this invention.
2 is a diagram schematically showing the configuration of a heat treatment system according to a second embodiment of the present invention.
3 is a diagram schematically showing the configuration of a heat treatment system according to a third embodiment of the present invention.

EMBODIMENT OF THE INVENTION Below, embodiment of this invention is shown, and the characteristic of this invention is demonstrated concretely.

<First embodiment>

1 : is a figure which shows typically the structure of the heat processing system 10 in 1st Embodiment of this invention. The heat treatment system 10 in the first embodiment includes a heat treatment furnace 1 , a reaction section 2 , a reaction gas supply section 3 , and a circulation furnace 4 .

The heat treatment furnace 1 is a furnace for performing heat treatment on an object, and includes a heating means H1 such as a heater. The heat treatment furnace 1 in this embodiment is a batch type heat treatment furnace. There is no particular restriction on the type of heat treatment performed in the heat treatment furnace 1, and for example, a firing treatment or a degreasing treatment for manufacturing a ceramic electronic component may be used, or a drying treatment for the object to be treated may be used. The volume of the heat treatment furnace 1 is, for example, 0.5 m 3 or more and 10 m 3 or less.

As the heat treatment is performed in the heat treatment furnace 1 , gas is generated after heat treatment including the first component. The first component is a component that inhibits the heat treatment in the heat treatment furnace 1 and is, for example, H ₂ , CO, CO ₂ or the like. On the other hand, the first component, which is a component that inhibits the heat treatment, varies depending on the content of the heat treatment. For example, in some heat treatment systems, CO ₂ is the first component, but in other heat treatment systems, CO ₂ does not inhibit the heat treatment and thus does not become the first component in some cases.

The heat treatment furnace 1 is provided with an exhaust pipe 11 for discharging unnecessary gas and maintaining a constant amount of gas in the heat treatment system 10 .

The reaction unit 2 reacts the first component included in the gas after heat treatment generated by the heat treatment in the heat treatment furnace 1 with the second component included in the reaction gas, thereby generating the regenerated gas in which the first component is reduced. is to get For example, when a _1st component is H2, let the _2nd component be O2. That is, as shown in the following formula (1), by reacting H ₂ with O ₂ , a regeneration gas containing H ₂ O as a third component is obtained.

2H ₂ +O ₂ =2H ₂ O (1)

In addition, when a 1st component is CO, let a _2nd component be O2. That is, the regeneration gas containing CO2 which is a _3rd component is obtained by making CO and O2 react according to the reaction formula shown in following Formula ( ₂ ).

2CO+O ₂ =2CO ₂ (2)

In addition, when a 1st component is solvent, such as acetone and terpineol, let the _2nd component be O2. That is, by burning acetone or terpineol, a regenerated gas in which acetone or terpineol is reduced is obtained. However, the second component for burning acetone or terpineol is not limited to O ₂ , and it is possible to use components containing oxygen atoms, such as air, H ₂ O, and CO ₂ .

In this way, the second component reacts with the first component, and a component capable of annihilating or reducing the first component is used.

The reaction unit 2 includes a heating means H2 such as a heater, and is configured to enable temperature control independent of the heat treatment furnace 1 . The reaction unit 2 for reacting the first component and the second component does not require a volume as large as that of the heat treatment furnace 1, for example, the size of 10% or more and 20% or less of the volume of the heat treatment furnace 1 do it with

In the present embodiment, the reaction unit 2 has an inlet 2a for introducing the gas after heat treatment, and an outlet 2b for introducing the regeneration gas to the circulation path 4 separately from the inlet 2a.

The reaction gas supply unit 3 supplies the reaction gas including the second component to the reaction unit 2 . The flow rate of the reaction gas supplied from the reaction gas supply unit 3 to the reaction unit 2 is controlled by a control unit 7 to be described later.

The circulation furnace 4 is a gas pipe for introducing the gas after heat treatment generated in the heat treatment furnace 1 into the reaction unit 2 and the regeneration gas obtained from the reaction unit 2 into the heat treatment furnace 1 . The circulation path 4 is between the gas outlet 1a of the heat treatment furnace 1 and the inlet 2a of the reaction section 2 , and the outlet 2b of the reaction section 2 and the gas of the heat treatment furnace 1 . It connects between the inlets (1b).

The heat treatment system 10 in the present embodiment includes a blower 5 for circulating gas through the circulation path 4 by blowing. That is, the blower 5 introduces the gas after heat treatment from the heat treatment furnace 1 to the reaction section 2 from the heat treatment furnace 1 through the circulation furnace 4 by blowing, and the regenerated gas obtained from the reaction section 2 is transferred to the heat treatment furnace ( 1) to create a flow of gas to be introduced. The blower 5 is, for example, a fan, and is provided in the circulation path 4 . By circulating gas by blowing by the blower 5, compared with the configuration in which the blower 5 is not provided, the amount of gas injected into the heat treatment system 10 is, for example, 10 times or more and 100 times or less. can produce a positive gas flow. Since the amount of gas required for heat treatment can be reduced by increasing the flow rate of the gas, the amount of gas injected into the heat treatment system 10 can be reduced, for example, to about 1/10 in this embodiment.

On the other hand, when the regenerated gas obtained in the reaction unit 2 is at a high temperature, the regenerated gas may be cooled and then returned to the heat treatment furnace 1 .

The heat treatment system 10 in this embodiment includes a sensor 6 for detecting at least one of the presence and concentration of at least one of the first component, the second component, and the third component included in the regeneration gas; It further includes a control unit 7 for controlling the flow rate of the reaction gas supplied from the reaction gas supply unit 3 to the reaction unit 2 based on the detection result of the sensor 6 .

The sensor 6 is a sensor for detecting the amount of the first component included in the regeneration gas introduced into the heat treatment furnace 1, and in the circuit 4, the outlet 2b of the reaction unit 2 and the heat treatment furnace It is provided between the gas inlets 1b of (1), for example, near the gas inlets 1b of the heat treatment furnace 1 . In order to grasp the degree of reduction of the first component, it is preferable to detect at least one of the presence or absence and concentration of the first component included in the regeneration gas by the sensor 6 .

However, compared with the first component, when the detection accuracy of the second component or the third component by the sensor 6 is higher, the presence or absence of the second component or the third component included in the regeneration gas by the sensor 6 and at least one of concentration may be detected. Since the second component in the reaction gas supplied to the reaction unit 2 by the reaction gas supply unit 3 reacts with the first component and disappears, for example, the concentration of the second component contained in the regeneration gas is measured by a sensor ( By detecting by 6), the concentration of the first component can be indirectly detected. In addition, since the third component is generated by the reaction of the first component and the second component, for example, by detecting the concentration of the third component contained in the regeneration gas by the sensor 6, the first component is indirectly information on the concentration of In order to improve detection accuracy, the sensor 6 may detect any two or three components among the first component, the second component, and the third component contained in the regeneration gas. Moreover, you may make it obtain the measurement result with higher precision by providing the sensor 6 in several places, and calculating|requiring the average value of several detection values.

The gas to be detected by the sensor 6 is, for example, O ₂ , H ₂ , H ₂ O, CO ₂ , SO ₂ , SO or the like. The temperature of the detection target gas at the time of use of the sensor 6 is 20 degreeC or more and 1400 degrees C or less, for example. As the sensor 6, it is possible to use, for example, a semiconductor gas sensor, a solid electrolyte gas sensor, or a non-dispersive infrared gas sensor. The internal resistance of the sensor 6 is, for example, 1000 kΩ or less.

A recorder may be connected to the sensor 6, and the detection result of the detection target gas may be recorded in the recorder. In that case, the internal resistance of the recording system is, for example, 1 MΩ or more and 1000 MΩ or less. The gas detection system including the sensor 6 and the recorder may include electrical circuit components such as an analog signal converter, a signal amplifier, a noise filter, a digital signal converter, a resistor, and an isolator.

You may make it provide another gas sensor separately in the heat treatment furnace 1 . In that case, determination of the presence or absence of the detection target gas or measurement of the concentration or partial pressure is performed by another gas sensor, and the gas in the heat treatment furnace 1 is determined according to the output of the other gas sensor or recorder or a value digitally processed from the output. The introduction amount and wind speed, the temperature and pressure in the heat treatment furnace may be adjusted, or an emergency stop or maintenance of the heat treatment furnace 1 may be instructed.

As described above, the control unit 7 controls the flow rate of the reaction gas supplied from the reaction gas supply unit 3 to the reaction unit 2 based on the detection result of the sensor 6 . Specifically, the control unit 7 determines the target flow rate of the reaction gas based on at least one of the presence and concentration of the first component, the second component, and the third component detected by the sensor 6 , and The flow rate of the reaction gas supplied from the supply unit 3 to the reaction unit 2 is controlled to be a target flow rate. In other words, the control unit 7 controls the reaction gas including the second component for reacting with the first component based on at least one of the presence and concentration of the first component detected directly or indirectly by the sensor 6 . A target flow rate is determined, and the flow rate of the reaction gas supplied from the reaction gas supply unit 3 to the reaction unit 2 is controlled to be the target flow rate. For this reason, the control unit 7 may be configured to include a mass flow controller capable of controlling the flow rate of the reaction gas supplied from the reaction gas supply unit 3 to the reaction unit 2 to be a target flow rate.

As described above, based on the detection result of the sensor 6 , the control unit 7 controls the flow rate of the reaction gas supplied from the reaction gas supply unit 3 to the reaction unit 2 , so that the first Since the flow rate of the reaction gas including the second component for reacting with the component can be appropriately controlled, the first component included in the gas after the heat treatment can be effectively reduced.

According to the heat treatment system 10 in the present embodiment, the first component contained in the gas after heat treatment generated by the heat treatment in the heat treatment furnace 1 is converted into the first component contained in the reaction gas supplied to the reaction unit 2 . By reacting with the two components, a regenerated gas in which the first component is reduced is obtained. By returning the obtained regenerated gas to the heat treatment furnace 1 , it is possible to reduce the amount of gas newly introduced into the heat treatment system 10 , while reducing the first component that adversely affects the heat treatment. As an example, when the first component is a solvent such as acetone or terpineol, the concentration of the solvent contained in the regeneration gas obtained in the reaction unit 2 can be reduced to 5% or less.

<Second embodiment>

2 : is a figure which shows typically the structure of 10A of heat processing systems in 2nd Embodiment. The heat treatment system 10A in the second embodiment further includes a reduction unit 20 with respect to the configuration of the heat treatment system 10 in the first embodiment.

The reduction unit 20 uses at least one method of filtration, separation, adsorption, condensation, and dissolution of the third component generated by the reaction of the first component and the second component from the regenerated gas obtained in the reaction unit 2 . reduced by

Here, as an example, it is assumed that the solder reflow treatment is performed in the heat treatment furnace 1 , the first component is a flux that is a soldering accelerator, the second component is O ₂ , and the third component included in the regeneration gas is water vapor (H ₂ O) ) to be explained. That is, by burning the flux, a regenerated gas with reduced flux is obtained. However, the second component for burning the flux is not limited to O ₂ , and it is possible to use a component containing oxygen atoms, such as air, H ₂ O, and CO ₂ .

The reduction unit 20 in this embodiment cools the regeneration gas introduced into the heat treatment furnace 1 from the reaction unit 2 through the circulation path 4 to condense water vapor as a third component, and is obtained by condensation Water (H ₂ O) is recovered. For example, in a double-tube structure in which a cooling tube is provided as a reduction unit 20 on the outside of the circulation path 4 between the outlet 2b of the reaction unit 2 and the gas inlet 1b of the heat treatment furnace 1 . and cooling the regenerated gas flowing through the circulation path 4 inside the double pipe by flowing cooling water through the cooling pipe. A trap device is provided in the cooling tube to recover water obtained by condensation.

According to this configuration, when the third component contained in the regeneration gas inhibits the heat treatment in the heat treatment furnace 1, the third component contained in the regeneration gas is reduced in the reduction unit 20, and then the heat treatment furnace ( 1) can be introduced. That is, when the first component, which is a component that inhibits heat treatment, is reduced by the reaction by the reaction unit 2, even when a third component, which is a component that inhibits heat treatment, is generated, the regenerated gas in which the third component is reduced is produced. It can introduce into the heat treatment furnace 1 . Accordingly, even when the regenerated gas introduced into the heat treatment furnace 1 contains a third component that inhibits heat treatment, while reducing the amount of gas newly introduced into the heat treatment system 10A, it is generated by heat treatment and The first component and the third component having a bad influence can be reduced.

In addition, if it is possible to reduce not only the third component in the reduction unit 20 but also the first component by at least one of filtration, separation, adsorption, condensation, and dissolution, the first component is removed in the reaction unit 2 The amount to be reacted may be reduced, and the remainder may be reduced in the reduction unit 20 . For example, when the first component is reduced by burning the first component in the reaction unit 2 , the reduction unit 20 does not completely burn the first component but reduces it by a method such as condensation. By doing so, the amount of O ₂ which is the second component supplied to the reaction unit 2 can be reduced.

<Third embodiment>

3 : is a figure which shows typically the structure of the heat processing system 10B in 3rd Embodiment. The heat treatment system 10B in this embodiment also has a heat treatment furnace 1, a reaction unit 2, a reaction gas supply unit 3, a circulation path 4, and a sensor, similarly to the heat treatment system 10 in the first embodiment. (6) and a control unit (7).

The heat treatment furnace 1 in the present embodiment is a continuous heat treatment furnace such as a muffle furnace or a tunnel furnace. On the other hand, FIG. 3 schematically shows a cross section orthogonal to the extending direction of the continuous heat treatment furnace 1 . A circulation furnace 4 is connected to the heat treatment furnace 1 . Specifically, one end of the circulation furnace 4 is connected to the gas outlet 1a of the heat treatment furnace 1 , and the other end is connected to the gas inlet 1b of the heat treatment furnace 1 .

The heat treatment system 10B in the present embodiment further includes a gas amplifier 30 for circulating the gas through the circuit 4 using compressed gas. The gas amplifier 30 is provided in the circuit 4, amplifies the amount of input gas by, for example, 2 times or more and 10 times or less, so that an output is possible. The compressed gas is, for example, compressed air. In this embodiment, the heat treatment furnace 1, the circulation furnace 4, and the gas amplifier 30 are provided in a space provided with heating means H3, such as a heater. For this reason, as a heat-resistant member, the gas amplifier 30 is provided instead of the fan. However, you may make it the circulation path 4 provide the ventilation part 5, for example, a fan.

In the present embodiment, the circuit 4 is configured as the reaction unit 2 . That is, the reaction gas supply unit 3 supplies the reaction gas including the second component to the circulation path 4 . The second component supplied to the circulation furnace 4 reacts with the first component contained in the gas after heat treatment generated by the heat treatment in the heat treatment furnace 1 , and a regenerated gas in which the first component is reduced is obtained.

For example, the first component is H ₂ and the second component is O ₂ . In this case, H ₂ as the first component and O ₂ as the second component react in the circuit 4 to obtain a regenerated gas containing H ₂ O as the third component.

The sensor 6 is provided near the outlet of the circuit 4 , that is, near the gas inlet 1b of the heat treatment furnace 1 . Also in the present embodiment, the sensor 6 detects at least one of the presence and concentration of at least one of the first component, the second component, and the third component included in the regeneration gas.

However, the sensor 6 may be provided on the upstream side of the circuit 4 , that is, between the position where the reaction gas is supplied to the circuit 4 by the reaction gas supply unit 3 and the gas amplifier 30 . When the sensor 6 is provided in the portion between the gas inlet 1b of the gas amplifier 30 and the heat treatment furnace 1 in the circuit 4, the flow of gas using compressed air by the gas amplifier 30 is reduced. As a result, the gas detection accuracy by the sensor 6 may become unstable. In such a case, by providing the sensor 6 between the position where the reactive gas is supplied to the circuit 4 by the reactive gas supply unit 3 and the gas amplifier 30, the gas detection accuracy by the sensor 6 is improved. can be improved

In addition, between the position where the reaction gas is supplied to the circuit 4 by the reaction gas supply unit 3 and the gas amplifier 30 , and between the gas amplifier 30 and the gas inlet 1b of the heat treatment furnace 1 , respectively You may make it provide the sensor 6 in this. In that case, the control unit 7 can control the flow rate of the reaction gas supplied from the reaction gas supply unit 3 to the reaction unit 2 based on the detection results of the sensors 6 provided at two locations, so that the reaction unit ( The flow rate of the reaction gas supplied to 2) can be controlled more precisely. For example, in the case of detecting the concentration of gas by the sensor 6 , based on the difference or average value of the gas concentrations detected by the two sensors 6 , the reaction gas supply unit 3 is supplied to the reaction unit 2 . It is possible to control the flow rate of the reaction gas supplied to the

The present invention is not limited to the above embodiments, and various applications and modifications can be made within the scope of the present invention. In addition, the characteristic structures demonstrated in each embodiment can be combined suitably.

1: Heat treatment furnace 1a: Gas outlet
1b: gas inlet 2: reaction part
2a: inlet 2b: outlet
3: reaction gas supply part 4: circulation path
5: Blower 6: Sensor
7: control unit 10, 10A, 10B: heat treatment system
11: exhaust pipe 20: reduction part
30: gas amplifier

Claims (7)

a heat treatment furnace for performing heat treatment;
a reaction unit for obtaining a regenerated gas in which the first component is reduced by reacting a first component included in the gas after heat treatment generated by the heat treatment in the heat treatment furnace and a second component included in the reaction gas;
a reaction gas supply unit for supplying the reaction gas to the reaction unit;
and a circulation path for introducing the gas after the heat treatment into the reaction unit and introducing the regeneration gas obtained from the reaction unit into the heat treatment furnace. According to claim 1,
The heat treatment system, characterized in that the reaction unit has an inlet for introducing the gas after the heat treatment, and an outlet for introducing the regeneration gas to the circulation path separately from the inlet. According to claim 1,
Detecting at least one of the presence and concentration of at least one of the first component, the second component, and the third component generated by the reaction of the first component and the second component included in the regeneration gas sensor for
The heat treatment system according to claim 1, further comprising a control unit for controlling a flow rate of the reaction gas supplied from the reaction gas supply unit to the reaction unit based on the detection result of the sensor. According to claim 1,
Further comprising a reduction unit for reducing a third component generated by the reaction of the first component and the second component from the regeneration gas by at least one of filtration, separation, adsorption, condensation, and dissolution Heat treatment system, characterized in that. According to claim 1,
The heat treatment system according to claim 1, further comprising a blower for circulating gas through the circulation path by blowing. 6. The method according to any one of claims 1 to 5,
The heat treatment system, characterized in that the circuit is configured as the reaction unit. 7. The method of claim 6,
and a gas amplifier for circulating gas through the circuit using compressed gas.

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