JP3616485B2 - Drying furnace wall surface processing object penetration part sealing device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention provides an opening of a drying furnace through which a workpiece can penetrate in an inert drying furnace in which the atmosphere gas in the drying furnace is substantially replaced with an inert gas and the solvent concentration in the drying furnace is maintained at a high concentration. The present invention relates to a sealing device for efficiently suppressing intrusion of outside air from the inside and leakage of gas in the furnace and maintaining an inert atmosphere.
[0002]
[Prior art]
Conventionally, an object to be treated containing a solvent (for example, a substrate coated with a coating liquid in which a solid component such as a pigment is dispersed in a solvent) is continuously conveyed by a belt-like web type or continuous conveyor type conveying means. In general, drying apparatuses that are introduced into a drying furnace and heat and evaporate a solvent in a coating liquid are widely used in various industrial fields.
[0003]
In such a drying apparatus, in general, drying is performed by a method (air mode) of drying a solvent-containing object to be processed in air. On the other hand, as described in JP-B-55-36389, A drying furnace that safely increases the solvent concentration in the atmosphere while substituting the atmosphere with an inert gas such as nitrogen gas and reducing the oxygen concentration to prevent the explosion and combustion of the evaporated solvent gas. It is disclosed.
[0004]
By the way, the drying furnace has an opening through which an object to be processed communicated with the outside air through the internal atmosphere (hereinafter referred to as a drying furnace opening).
[0005]
Accordingly, in the inert gas atmosphere (inert mode) type drying furnace, an increase in oxygen concentration due to intrusion of outside air from the opening is accompanied by a risk of explosion and combustion due to a high concentration organic solvent gas.
[0006]
Therefore, the inert type drying furnace narrows the gap of the opening of the drying furnace as much as possible by a slide plate or the like, suppresses intrusion of outside air, and blows nitrogen gas into the object to be processed in the opening of the drying furnace in a slit shape, A sealing device that shuts off the internal gas and the outside air has also been devised. On the other hand, in order to suppress the dynamic pressure of the gas blown from the blow nozzle for drying in the drying furnace and for conveying the workpiece (floating), it is dried from the blow nozzle. A space (buffer zone) for buffering dynamic pressure by taking a distance to the furnace opening is provided in the drying furnace opening, and various other sealing structures have been devised.
[0007]
In this manner, the space in the drying furnace inerted with nitrogen gas causes gas to enter and exit from the opening of the drying furnace due to the effect of pressure balance due to the circulation of the gas for generating the drying air from the blowing nozzle. The inert type drying furnace is basically uniform in mass balance because it incorporates solvent recovery by a closed circulation system, and when gas comes out from one drying furnace opening, gas is sucked from the other drying furnace opening. As a result, a gas flow occurs in the drying furnace, and as a result, the oxygen concentration increases from the gas suction side in the drying furnace, and nitrogen gas containing a solvent is blown out from the opening on the opposite side of the drying furnace. .
[0008]
Normally, in a space where an inert atmosphere is maintained, a mass balance is established between the amount of nitrogen gas supplied to the sealing device provided at the opening of the drying furnace and the amount of gas entering and leaving the drying furnace. If it is large, it will be difficult to maintain the inert atmosphere.
[0009]
In general, an inert drying furnace has no danger of explosion or combustion even if the solvent concentration exceeds the lower explosion limit (LEL). Therefore, a closed circulation system solvent recovery system (Japanese Patent Publication No. 3-25228) In order to efficiently perform the condensation recovery of the solvent gas in the description), the solvent concentration in the drying furnace is operated at a somewhat high concentration (in the range of LEL to about 30 mol%). Therefore, when nitrogen gas containing such a high concentration of solvent gas flows out from the opening of the drying furnace, the surrounding environment is insufficient if the ventilation is insufficient, or in the worst case, the retained solvent gas causes There is a risk of explosion.
[0010]
As a measure against this, Japanese Patent Publication No. 8-7025 discloses a gas that flows out of the drying furnace along the surface of the object to be processed from the opening of the drying furnace by means of a sealing plate that is brought close to the object to be processed and whose tip is bent inside the furnace. A seal structure that suppresses the blow-out is disclosed. However, in this method, the effect does not appear unless the seal plate is brought close to the object to be processed.However, a certain amount of gap is provided so that the seal plate does not come into contact with the undulation of the object to be processed by blowing dry air from the blowing nozzle. Must be provided. In particular, a shape in which the workpiece is floated by blowing from the upper and lower blowing nozzles needs to have a larger gap. As described above, it is difficult to sufficiently suppress the leaked gas in the seal structure using the seal plate.
[0011]
Also, even if the mass balance of the drying furnace space can be maintained under a certain condition, if the pressure balance in the drying furnace changes, or if the pressure of the outside air around the opening changes, Maintaining the mass balance of the drying furnace space is disrupted.
[0012]
In addition, when the processing speed (traveling speed) of the object to be processed is high (for example, 100 m / min or more), the inertia due to the frictional force (drag force) on the surface of the object to be processed and the space in the drying furnace together with the object to be processed Entrained air may change the pressure balance in the drying apparatus and disrupt the maintenance of the inert atmosphere.
[0013]
In particular, there is a problem in that it cannot follow a change in pressure balance accompanying a change in the amount of entrained gas movement due to a surface friction force due to a significant change in the processing speed or a change in the material to be processed.
[0014]
As a result, there are cases where oxygen in the external air enters the drying furnace due to such a change in pressure balance, and in order to maintain the inert atmosphere, there is a case where an excessive supply of nitrogen gas is forced. Increases running costs due to consumption.
[0015]
In the above-mentioned Japanese Patent Publication No. 8-7025, a seal box communicating with a drying furnace opening on the wall surface of the drying furnace is provided, and an exhaust passage and an inert gas supply passage are provided in the seal box. Although a configuration with a circulation path is disclosed, this circulation path is merely for returning excess gas into the drying furnace, and as described above, it cannot follow the change in the pressure balance in the drying furnace. The problem still remains.
[0016]
[Problems to be solved by the invention]
The present invention has been made to solve the above-mentioned problems, and the object of the present invention is to provide nitrogen gas by means of a sealing device for correcting the balance against changes in the pressure balance in the drying furnace. An object of the present invention is to provide an apparatus for sealing an object to be processed on the wall of a drying furnace capable of reducing the supply amount of gas and reducing the release of gas containing a high-concentration solvent.
[0017]
[Means for Solving the Problems]
A drying object wall surface sealing device for a drying furnace wall surface according to the present invention has a drying furnace wall surface for reducing the flow of gas through a first opening through which a processing object provided on the wall surface of the drying furnace can pass. A to-be-processed object through-portion sealing device, which is provided in communication with the first opening of the drying furnace and has a second opening through which the object to be processed can pass, A pressure adjusting chamber having a third opening disposed outside the seal box; means for supplying an inert gas into the seal box; and detecting a gas flow through the first opening. Means, and pressure adjusting means of the pressure adjusting chamber for reducing the detected gas flow rate, whereby the above object is achieved.
[0018]
Moreover, the other object penetration part sealing device of the drying furnace wall surface of this invention is for reducing the distribution | circulation of the gas through the 1st opening part which the to-be-processed object provided in the wall surface of the drying furnace can penetrate. An apparatus for sealing an object to be processed through the drying furnace wall, the apparatus being provided in communication with the first opening of the drying furnace, and having a second opening through which the object to be processed can penetrate. A seal box, a pressure adjusting space provided in the seal box and sharing the second opening through which the object can pass, and means for supplying an inert gas into the seal box; Means for supplying and / or removing air into the pressure adjustment space, means for detecting the flow of gas through the first opening, and the pressure adjustment space for reducing the flow rate of the detected gas. Pressure adjusting means, whereby the above object is achieved. .
[0019]
In one embodiment, the means for detecting the flow of the gas flowing through the first opening is a pressure difference signal between the first opening side in the seal box and the pressure adjustment chamber, or an inlet in the drying furnace. This is done by the deviation signal of the oximeter measurement values on the side and outlet side.
[0020]
In one embodiment, the means for detecting the flow of the gas flowing through the first opening is a pressure difference signal in the seal box and the pressure adjustment space or oxygen on the inlet side and outlet side in the drying furnace. This is done by the deviation signal of the densitometer measurement value.
[0021]
In one embodiment, the gas flow rate adjusting means includes an air supply adjusting valve provided in an air supply means and / or an exhaust adjusting valve provided in an exhaust means in the pressure adjusting chamber or the pressure adjusting space. It is done by opening and closing.
[0022]
In one embodiment, the gas flow rate adjusting means is performed by adjusting the pressure with a suction gas adjusting valve installed in a pipe for returning the gas in the seal box to the drying furnace with a fan.
[0023]
In one embodiment, the gas flow rate adjusting means is a gas inflow / outflow adjusting means for the seal box in an inert solvent recovery apparatus connected to a drying furnace.
[0024]
Next, the operation of the present invention will be described.
[0025]
Normally, the gas moves to a lower side than a higher one. Therefore, when the pressure in the drying furnace is higher than the external pressure, gas flows out from the inside through the drying furnace opening, and in the opposite case, gas (generally, external air) flows in the opposite direction. . If this pressure difference is 1 mmAq, for example, the gas moves at a flow rate of about 4 m / sec, and this pressure difference is proportional to the square of the gas flow rate. In general, in order to maintain the inert atmosphere, the amount of gas movement when the opening gap above and below the object to be processed is divided into 10 mm (the gap is preferably as narrow as possible) is 1 m / sec or less (preferably 0.5 m). / Sec or less).
[0026]
Therefore, the inert atmosphere can be maintained by supplying a small amount of nitrogen gas to the drying furnace opening by maintaining the balance below the pressure difference corresponding to this.
[0027]
In the first aspect of the invention, the inert gas is supplied into the pressure adjustment chamber provided outside the seal box, and the gas flow through the first opening of the drying furnace is detected by the detection means, and the gas By reducing the flow rate by adjusting means, the pressure balance in the drying furnace can be maintained below a predetermined value, and an inert atmosphere can be maintained by supplying a small amount of nitrogen gas to the opening of the drying furnace. I can do it.
[0028]
In the second invention, an inert gas is supplied into the seal box, and the adjusting means for detecting the gas flow through the first opening by the detecting means and reducing the gas flow rate. By supplying and / or eliminating air in the pressure adjustment space, the pressure balance in the drying furnace can be maintained below a predetermined value, and an inert atmosphere can be created by supplying a small amount of nitrogen gas to the opening of the drying furnace. Can be maintained.
[0029]
DETAILED DESCRIPTION OF THE INVENTION
(Example 1)
The present invention will be specifically described based on examples.
[0030]
FIG. 1 is a cross-sectional view of an example of a sealing device in a workpiece penetration part on the drying furnace outlet side, showing a basic embodiment of the present invention.
[0031]
The sealing device of the present embodiment is for reducing the flow of the gas in the furnace from the first opening 4 provided on the wall surface of the drying furnace 2 through which the workpiece 1 can penetrate, and the sealing device. Is a seal box 5 provided on the wall surface of the drying furnace 2 so as to communicate with the first opening 4 of the drying furnace 2, and a pressure adjustment chamber 9 provided on the downstream side of the seal box 5, Have The pressure adjusting chamber 9 is disposed outside the seal box 5 so as to cover the seal box 5.
[0032]
The seal box 5 is provided with a second opening 37 through which the workpiece 1 can penetrate, corresponding to the first opening 4 of the drying furnace 2, and the pressure adjustment chamber 9 is similarly covered. A third opening 18 through which the processing body 1 can penetrate is formed.
[0033]
A nitrogen gas supply pipe 6 is connected to the seal box 5 as means for supplying an inert gas into the seal box 5. In addition, orifices 7a and 7b for spraying at an arbitrary angle with respect to the traveling direction toward the front surface and the back surface of the object 1 are provided in the seal box 5 respectively. Furthermore, slide plates 8 a and 8 b that can open and close the second opening 37 are provided on the outside of the seal box 5. With the slide plates 8a and 8b, it is preferable to narrow the gap of the second opening 37 as much as possible within a range that does not affect the travel of the object 1 to be processed.
[0034]
Further, as means for supplying and removing air into the pressure adjustment chamber 9, an air supply pipe 10 having an air supply adjustment valve 16 and an exhaust pipe 11 having an exhaust adjustment valve 17 are connected to the pressure adjustment chamber 9. .
[0035]
Then, a differential pressure gauge 14 measures the pressure difference between the pressure detection unit 12 disposed in the seal box 5 and the pressure detection unit 13 disposed in the pressure adjustment chamber 9, and the signal and the control unit are measured. The flow rate is adjusted by operating the air supply adjustment valve 16 and the exhaust adjustment valve 17 according to the deviation from the value set to 15 (basically, the set differential pressure is 0) (Either supply air or exhaust gas can be adjusted). Possible), the pressure in the pressure adjusting chamber 9 is controlled, and the gas blowout (or air suction) from the second opening 37 of the seal box 5 is suppressed.
[0036]
In this pressure adjusting chamber 9 as well, pressure adjustment is performed by supplying and exhausting air. Therefore, it is preferable to reduce the cross-sectional area of the third opening 18 through which the workpiece 1 can penetrate, and the opening is the same as that of the seal box 5. Slide plates 19a and 19b are provided in the portion 18 so as to be openable and closable.
[0037]
In the inert type drying apparatus provided with the sealing device having the above-described configuration, the object to be processed 1 is a coating liquid applied to the surface by the gas blown from the blowout nozzle 3 in the drying furnace 2 which has been inerted with nitrogen gas. Is dried and conveyed from the first opening 4 to the right side of the figure (in the direction of the arrow) and passes through the second opening 37 of the seal box 5 and the third opening 18 of the pressure adjusting chamber 9. By circulating a gas containing a solvent using the inert drying furnace 2 as a closed circulation system and providing a solvent recovery device such as a condenser in the circulation system, the solvent in the atmosphere can be recovered.
[0038]
Here, in the seal box 5, as described above, nitrogen gas is supplied from the nitrogen gas supply pipe 6, and the upper and lower orifices 7 a and 7 b inside the seal box 5 are used to travel the front and back surfaces of the workpiece 1. Spray at any angle. A differential pressure between the pressure 12 in the seal box 5 and the pressure 13 in the pressure adjusting chamber 9 is measured by a differential pressure gauge 14 and the value set in the control unit 15 (basically, the set differential pressure is 0) Therefore, the flow rate is adjusted by the air supply adjustment valve 16 and the exhaust adjustment valve 17 (either air supply or exhaust can be adjusted), and the pressure in the pressure adjustment chamber 9 is controlled, that is, the seal box. By setting the pressure in 5 and the pressure in the pressure adjusting chamber 9 to be approximately equal, the blowing (or suction) of gas from the second opening 37 of the seal box 5 is suppressed.
[0039]
Although the said Example demonstrated the 1st opening part 4 by the side of the exit of the drying furnace 2, it is also possible to provide the sealing apparatus of the same structure in the entrance side of the drying furnace 2. FIG.
[0040]
(Example 2)
FIG. 2 illustrates a second embodiment in which the embodiment shown in FIG. 1 is improved.
[0041]
A feature of the embodiment of FIG. 2 is that a pressure adjusting function by the pressure adjusting chamber 9 of FIG. FIG. 2 shows a cross-sectional structure of the sealing device on the inlet side and outlet side of the drying furnace 2.
[0042]
The workpiece 1 is dried by the gas blown from the blowout nozzle 3 while moving from the left side to the right side in the drying furnace 2 that has been inerted with nitrogen gas.
[0043]
Sealing boxes 5 are installed on the wall surfaces on the inlet side and the outlet side of the drying furnace 2 so as to communicate with the first opening 4 in order to maintain the inert state of the atmosphere.
[0044]
The seal box 5 is provided with a buffer space 20 on the first opening 4 side of the drying furnace 2 for buffering and weakening the dynamic pressure due to the blowing of the blowing nozzle 3 in the drying furnace 2. In order to efficiently buffer the dynamic pressure, a plurality of partition plates 21 are provided in the buffer space 20 with the gap as narrow as possible in the object 1 (to add resistance to the dynamic pressure). Weaken by things). A nitrogen gas space 40 for sealing is formed outside the sealing nitrogen gas blowing orifices 7a and 7b. Further, a pressure adjustment space 22 corresponding to the pressure adjustment chamber 9 in FIG. 1 is provided outside the seal box 5 so that pressure can be applied from the air supply pipe 10.
[0045]
The adjustment method of the balance of maintaining the inert atmosphere in the sealing device of this configuration is the pressure measurement by the pressure detection unit 12 installed in the buffer space 20 and the pressure measurement by the pressure detection unit 13 installed in the pressure adjustment space 22. The differential pressure is measured by the differential pressure gauge 14, and the amount of air supplied to the pressure adjustment space 22 on the inlet side and the outlet side of the drying furnace 2 is determined by the difference between the signal and the control unit 15. Adjust by opening and closing. For example, when the differential pressure gauge 14 indicates that the pressure in the buffer space 20 is higher than the pressure in the pressure adjustment space 22, the gas in the vicinity of the opening 4 of the drying furnace passes through the first opening 4. Since the air is blown out through the air, the air regulating valve 16 a is opened to increase the pressure in the pressure regulating space 22 and supply air into the pressure regulating space 22. On the other hand, when the pressure in the pressure adjustment space 22 is high, the air supply adjustment valve 16a is actuated to close in order to reduce the pressure in the pressure adjustment space 22.
[0046]
Further, if the pressure in the pressure adjustment space 22 is still high even when the air supply adjustment valve 16a is fully closed, the air supply adjustment valve 16b of the seal box 5 at the opening of the drying furnace opposite to the drying furnace 2 is opened. Move in the direction and adjust the pressure.
[0047]
In addition, as a method for detecting whether or not nitrogen gas is flowing in the sealing device portion of the drying furnace, the oxygen concentration in the drying furnace is not limited to the method for detecting the differential pressure between the seal box 5 and the pressure adjustment space 22. Can also be implemented.
[0048]
An oxygen concentration meter 23 is installed on the inlet side of the drying furnace 2, and a predetermined signal is supplied from the control unit 25 based on the deviation between the detection output of the concentration meter 23 and the detection output of the oxygen concentration meter 24 installed on the outlet side. A feed opening degree is adjusted to the air regulating valves 16a and 16b. Also in this case, similarly to the pressure adjustment by the differential pressure, when the oxygen concentration on the inlet side of the drying furnace 2 is high, the air supply adjustment is performed in the direction of increasing the pressure in the pressure adjusting space 22 on the outlet side of the drying furnace 2. On the contrary, when the valve 16a is operated and the oxygen concentration on the outlet side is high, the reverse operation is performed.
[0049]
(Example 3)
The feature of the third embodiment shown in FIG. 3 is that the pressure adjustment function described in the second embodiment (FIG. 2) is performed by the suction gas from the buffer space 20.
[0050]
The buffer space 20 of the seal box 5 and the downstream side of the drying furnace 2 are connected by a return pipe 27 having a fan 26 and a suction gas regulating valve 28. The gas in the seal box 5 is sucked by the fan 26 and dried. By returning the gas to the furnace 2, the pressure in the buffer space 20 can be reduced.
[0051]
The pressure balance adjustment method for maintaining the inert atmosphere is basically the same as described in the second embodiment (FIG. 2), and the pressure in the buffer space 20 is determined from the measured value of the differential pressure gauge 14 as the internal pressure of the pressure adjustment space 22. If higher, the suction gas regulating valve 28 installed on the discharge side of the fan 26 of the return pipe 27 is opened to lower the pressure in the buffer space 20 to increase the amount of suction from the buffer space 20 and adjust the pressure. Do. Conversely, when the pressure in the buffer space 20 is low, the pressure is adjusted by decreasing the suction gas amount and increasing the suction amount of the seal box 5 in the opposite opening 4.
[0052]
Further, the pressure balance adjustment based on the deviation of the oxygen concentration is the same as that in the second embodiment, and is omitted here.
[0053]
(Example 4)
The characteristic of Example 4 shown in FIG. 4 is a solvent recovery method according to the inert method described in Japanese Patent Publication No. 3-25228. A part of the gas containing solvent vapor in the drying furnace is introduced into the condenser, In the solvent recovery system that constitutes a closed circulation system that condenses and recovers the solvent vapor by cooling and returns the remaining gas to the drying furnace, the pressure in the seal box 5 is adjusted using the gas in the closed circulation system. It is.
[0054]
The gas in the drying furnace 2 in which the inert atmosphere is constituted by nitrogen gas is sent to the condenser 31 by the fan 29 and the exhaust pipe 30, and is cooled here to condense and recover the solvent vapor. The remaining gas constitutes a circulation system that is returned to the drying furnace 2 by the return pipe 32 again. Nitrogen gas is supplied from the nitrogen gas supply pipe 6 to the orifices 7a and 7b to the seal box 5 installed outside the first opening 4 through which the workpiece 1 formed on the wall surface of the drying furnace 2 passes. , Blow out from the tip. The pressure adjustment space 22 is provided with a return gas supply pipe 33 for supplying a part of the gas from the return pipe 32 and a return gas adjustment valve 34 for adjusting the flow rate. On the other hand, a suction pipe 35 and a suction gas adjusting valve 36 for adjusting the flow rate are provided from the buffer space 20 so that gas can be sucked into the exhaust pipe 30.
[0055]
The balance adjustment method for maintaining the inert atmosphere is basically performed by the method shown in the second and third embodiments in FIGS. This can be done by adjusting the flow rate of the return gas adjusting valve 34 and the suction gas adjusting valve 36 by the pressure signal from the differential pressure gauge 14 or the deviation signal of the oximeters 23 and 24.
[0056]
【The invention's effect】
The effect of adjusting the pressure balance for maintaining the inert atmosphere in the drying furnace was recognized by the sealing device for the processing object penetration part of the drying furnace of the present invention. As a result, the flow rate of nitrogen gas for sealing can be reduced, and leakage of atmospheric gas containing high-concentration solvent vapor to the outside can be prevented, and reduction of running cost and improvement of environmental conservation are recognized.
[0057]
In particular, the pressure balance in the drying furnace can be adjusted automatically by detecting the pressure balance fluctuation in the drying furnace with a differential pressure gauge or oxygen concentration meter. For example, a change in the wind speed of the blowing nozzle, a change in the traveling speed of the object to be processed, and the like are particularly effective.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of an essential part of an embodiment of a sealing device of the present invention in which the pressure balance of an atmosphere in a drying furnace is adjusted by adjusting the pressure in a pressure adjusting chamber.
FIG. 2 is a cross-sectional view of an essential part showing another embodiment of the sealing device of the present invention in which the pressure balance of the drying furnace atmosphere is adjusted by adjusting the air supply amount in the pressure adjusting space in the seal box.
FIG. 3 is a partially cutaway cross-sectional view showing still another embodiment of the sealing device of the present invention in which the pressure balance of the drying furnace atmosphere is adjusted by adjusting the amount of gas suction from the buffer space in the seal box.
FIG. 4 is a cross-sectional view of an essential part showing still another embodiment of the sealing device of the present invention in which the pressure balance of the drying furnace atmosphere is adjusted by adjusting the gas flow in and out of the seal box in the closed circulation system solvent recovery device. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 To-be-processed object 2 Drying furnace 3 Blowing nozzle 4 1st opening part 5 Seal box 6 Nitrogen gas supply piping 7a, 7b Orifice 8a, 8b Slide plate 9 Pressure adjustment chamber 10 Supply pipe 11 Exhaust pipe 12 Pressure detection in a seal box Unit 13 Pressure detection unit 14 in pressure adjustment chamber Differential pressure gauge 15 Control unit 16, 16a, 16b Air supply adjustment valve 17 Exhaust adjustment valve 18 Third opening 19a, 19b of pressure adjustment chamber Slide plate 20 Buffer space 21 Partition plate 22 Pressure adjustment space 23 Inlet side oxygen concentration meter 24 Outlet side oxygen concentration meter 25 Control unit 26 Fan 27 Gas return pipe 28 Suction gas adjustment valve 29 Fan 30 Extraction pipe 31 Condenser 32 Return pipe 33 Return gas supply pipe 34 Return gas adjustment valve 35 Suction piping 36 Suction gas regulating valve 37 Second opening 40 Nitrogen gas space for sealing

Claims (7)

To reduce the circulation of gas through the first opening through which the object to be processed provided on the wall surface of the drying furnace can penetrate,
A seal box provided in communication with the first opening of the drying furnace and having a second opening through which the object can pass;
A pressure regulating chamber having a third opening disposed outside the seal box;
Means for supplying an inert gas into the seal box;
Means for detecting the flow of gas through the first opening;
Pressure adjusting means of the pressure adjusting chamber for reducing the flow rate of the detected gas;
A sealing device comprising: A processing object through-portion sealing device for a drying furnace wall for reducing the flow of gas through the first opening through which the object to be processed provided on the wall of the drying furnace can pass,
A seal box provided in communication with the first opening of the drying furnace and having a second opening through which the object can be passed;
A pressure adjusting space provided in the seal box and sharing the second opening through which the object to be processed can pass;
Means for supplying an inert gas into the seal box;
Means for supplying and / or excluding air into the pressure regulating space;
Means for detecting the flow of gas through the first opening;
Pressure adjusting means of the pressure adjusting space for reducing the flow rate of the detected gas;
A sealing device comprising: The means for detecting the flow of the gas flowing through the first opening is a pressure difference signal between the first opening side in the seal box and the pressure adjustment chamber, or oxygen on the inlet side and outlet side in the drying furnace. The sealing device according to claim 1, which is performed by a deviation signal of a densitometer measurement value. The means for detecting the flow of the gas flowing through the first opening is a pressure difference signal in the seal box and the pressure adjustment space, or a deviation signal of the oximeter measurement values on the inlet side and the outlet side in the drying furnace. The sealing device according to claim 2, wherein The pressure adjusting means is performed by opening and closing an air supply adjusting valve provided in an air supply means and / or an exhaust adjusting valve provided in an exclusion means in the pressure adjusting chamber or the pressure adjusting space. Or the sealing apparatus of 2. The sealing device according to claim 1 or 2, wherein the pressure adjusting means is performed by adjusting the pressure with a suction gas adjusting valve installed in a pipe for returning the gas in the seal box to the drying furnace with a fan. 3. The sealing device according to claim 1, wherein the pressure adjusting means is a gas inflow / outflow amount adjusting means for a seal box in an inert solvent recovery apparatus connected to a drying furnace.

Images