JP2531001Y2 - Gas cooler with mechanism to remove dust adhering to cooling pipe - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION This invention relates to a gas cooler for exhaust gas attached to a so-called CVD facility, in which a cooling pipe is used.
The present invention relates to a gas cooler having a mechanism for removing attached FeCl ₂ dust .

[0002]

2. Description of the Related Art As a method of manufacturing a high silicon steel sheet, a so-called C
A Si diffusion and infiltration treatment by a VD method (chemical vapor deposition method) is known. Usually, the production of high silicon steel sheet by this CVD method, in a facility provided with a heating zone of the steel sheet, CVD zone, soaking zone, cooling zone continuously, first, after heating the steel sheet to a predetermined temperature in the heating zone, Si compounds such as SiCl ₄ by CVD band (hereinafter, will be described as an example SiCl ₄₎ high temperature containing (usually about 1200 ° C. so) is subjected to siliconizing treatment (CVD process) at a non-oxidizing gas atmosphere After infiltrating Si from the surface of the steel sheet, and then subjected to a soaking diffusion treatment on the steel sheet in a non-oxidizing gas atmosphere containing no Si compound in the soaking zone, after diffusing the infiltrated Si into the steel sheet, Cool in the cooling zone.

[0003] In the above CVD band, always a certain amount of SiCl ₄ gas to enhance the purity of the SiCl ₄ gas is bubbler,
In addition, a certain amount of gas is discharged (exhaust gas). Since this exhaust gas is hot, it needs to be cooled before passing through a dust collector. In general, a gas cooler such as an indirect water cooling system is used for this cooling.

[0004]

The main components of the above exhaust gas are N ₂ (carrier gas), SiCl ₄ (reactive gas), F
Although it is eCl ₂ (reaction product gas), FeCl ₂ (iron chloride) solidifies when the temperature drops to 670 ° C or less and forms dust on the inner surface of the duct and other parts of the shell in the dust collection path.
And the deposit gradually grows.

In particular, in the above-mentioned gas cooler, a large number of cooling pipes are usually arranged in a direction orthogonal to the gas flow for the purpose of cooling the exhaust gas. Therefore, the adhesion of FeCl ₂ dust in this cooling pipe portion is remarkable. . If the adhesion and growth of dust to the cooling pipe part progresses, the gas cooler will eventually be clogged, and the line operation will have to be stopped.

[0006] The present invention has been made in view of such a conventional problem, and FeC adhered to the cooling pipe during operation.
l ₂ dust can be dropped easily pay, is intended to provide a gas cooler of a structure capable of preventing the growth of fouling by dust in the cooling pipe portion.

[0007]

In order to achieve the above object, the present invention provides a CV for performing a siliconizing treatment of a steel sheet.
Including SiCl ₄ and FeCl ₂ discharged from D equipment
A gas cooler for cooling exhaust gas, which has a number of cooling pipes arranged in parallel in a body, and in which a cooling pipe is slidably fitted in a gas cooler for performing gas cooling by passing exhaust gas between these cooling pipes. A dust removal plate having a plurality of insertion holes that can be inserted or loosely inserted, and the plurality of cooling pipes attached to the respective cooling holes so that the cooling pipes are inserted or loosely inserted into the respective insertion holes,
It consists of a moving mechanism for moving the dust brushing plate to the tube axis direction of the cooling pipe, a solid by cooling the exhaust gas
FeCl ₂ dust adhered to the cooling pipe surface
It is characterized by having a dust removing mechanism for removing by moving the strike removing plate .

In the present invention, one dust removing plate may be provided for the cooling pipe group of the gas cooler, or the cooling pipe group may be divided into two or more, and the dust removing plate may be provided for each pipe group. It may be. Further, the insertion hole of the dust removing plate is allowed to have a certain amount of play with respect to the outer periphery of the cooling pipe as long as dust attached to the cooling pipe can be removed.

[0009]

When the gas cooler is operated for a certain period in the CVD equipment, the gas components in the exhaust gas flow into the cooling pipe inside the cooler.
FeCl ₂ Das of FeCl ₂ was solidified by cooling it
(Hereinafter simply referred to as "dust") . At this time, the dust removing plate constituting the present invention is moved by the moving mechanism in the axial direction of the cooling pipe. Since each cooling pipe is slidably inserted or loosely inserted into the insertion hole of the dust removing plate, dust adhering to the cooling pipe surface is removed by the movement of the dust removing plate. Therefore, by periodically removing such dust, it is possible to prevent the growth of deposits due to dust on the surface of the cooling pipe. The blown-off dust falls below the cooler and is discharged and removed outside the machine by a suitable discharging means.

[0010]

1 and 2 show an embodiment of the present invention. In the figure, reference numeral 1 denotes a vertical gas cooler main body. An exhaust gas inlet 100 is provided at a lower portion of one side of the gas cooler main body 1, and an exhaust gas outlet 101 is provided at an upper portion of the other side. ing. A cooling pipe group A composed of a number of cooling pipes 2 is arranged in the vertical direction inside the gas cooler main body 1. Normally, cooling water flows through these cooling pipes.

A hopper-shaped dust reservoir 102 is provided at the lowermost portion of the gas cooler main body 1.
A dust discharge pipe 8 is connected to a lower end of the dust reservoir 102 via an on-off valve 7, and the dust discharge pipe 8 is guided to a dust receiving box 9. Also, the wall 1 of the gas cooler body 1
The inside of 0 has a fluid cooling structure in which a coolant flow path a through which a coolant such as cooling water flows is formed.

Numeral 3 denotes a dust removing plate. As shown in FIG. 2, the dust removing plate 3 has a large number of insertion holes 3 on its entire surface.
00, and each cooling pipe 2
Is slidably fitted or loosely fitted to the cooling pipe group A so as to be slidable in the pipe axis direction. As described above, the insertion hole 300 is allowed to have some play with respect to the outer periphery of the cooling pipe 2 as long as dust attached to the cooling pipe 2 can be removed.

In order to prevent the dust removing plate 3 from obstructing the flow of exhaust gas during normal operation, the dust removing plate 3 can be positioned above the exhaust gas outlet 101. As shown in FIG. 2, a predetermined space is provided between the periphery of the dust removing plate 3 and the inner wall of the gas cooler body 1 in order to secure gas flow inside the cooler when the dust removing plate 3 is moved up and down. Is provided.

Reference numeral 4 denotes a moving mechanism of the dust removing plate 3. The moving mechanism 4 includes a plurality of slide shafts 5 having one end fixed to the dust removing plate 3 and the other end extending outside the machine.
And a drive device 6 (cylinder device) that is connected to the slide shaft 5 outside the machine and moves the slide shaft 5 up and down.

According to the gas cooler having such a structure, C
Exhaust gas discharged from the VD equipment is introduced into the device through the inlet 100 and cooled while passing between the cooling pipes 2, then discharged from the outlet 101 and sent to the dust collector side. During normal operation, the dust removing plate 3 is located above the exhaust gas outlet 101 so as not to hinder the flow of the exhaust gas. The gas cooler is operated for a certain period of time, and when a certain amount of dust adheres to the cooling pipe group A, the dust removing plate 3 is slid downward by the drive mechanism 6 constituting the moving mechanism 4 as shown by the phantom line in FIG. Let it. Since each cooling pipe 2 is inserted or loosely inserted into the insertion hole 300 of the dust removing plate 3, the dust attached to the surface of the cooling pipe 2 is removed by the movement of the dust removing plate 3. . The dust that has been dropped falls into a dust reservoir 102 below the cooler, and when an appropriate amount of dust has accumulated, the on-off valve 7 is opened, and the dust container 9 is opened.
To be discharged.

FIGS. 3 to 7 show a more specific embodiment of the present invention, in which a U-shaped gas flow path is formed inside the gas cooler main body 1, and an exhaust gas flow is provided at an upper portion on one side X side. An inlet 100 is formed, and an exhaust gas outlet 101 is formed in the upper part on the other side Y side. A dust receiving bucket 11 is disposed at a U-shaped bottom Z of the gas flow path. By making the gas flow path inside the machine into a U-shape in this way, the dust contained in the exhaust gas is lowered to the U-shaped bottom (received by the dust receiving bucket 11), and the cooling pipe located downstream of the gas flow path The amount of dust reaching the group can be reduced.

A cooling pipe group A composed of a number of cooling pipes 2 is arranged downstream of the gas flow path, that is, on the other side Y side of the U-shaped gas flow path. Each of the cooling pipes 2 constituting the cooling pipe group A is disposed so as to horizontally cross a vertical gas flow path.

In this embodiment, the cooling pipe group A is divided into a plurality (five) groups in the vertical direction, and dust removing plates 3a to 3e are attached to the cooling pipe groups of these groups. Each dust removing plate has a large number of insertion holes 300 on the entire surface, and each cooling pipe 2 is slidably inserted or loosely inserted into this insertion hole 300,
Each cooling pipe group is slidably mounted in the pipe axis direction (horizontal direction).

Each of the dust removing plates 3a to 3e has:
Gland packing 12 and bush 13 for gas seal
Slide shaft 5 inserted into the machine through a seal made of
By sliding the slide shaft 5 in its longitudinal direction, each dust removing plate can be slid in the axial direction of the cooling pipe. The movement of the slide shaft 5 can be performed manually or by a drive mechanism as shown in FIG. In this embodiment, the interior of the wall 10 of the gas cooler main body 1 also
It has a fluid cooling structure in which a coolant flow path a through which a coolant such as cooling water flows is formed.

Further, a gas shut-off valve 16 capable of closing the inlet 100 is provided in the apparatus (in the gas flow path) as shown in FIGS. In a gas cooler that cools high-temperature and harmful exhaust gas such as exhaust gas discharged from a CVD facility, when the inside of the cooler is repaired or dust collected in the dust receiving bucket 11 described above is collected outside the machine, the inside of the cooler is cooled. It is necessary to completely shut off the supply of exhaust gas, and if this gas shutoff is not complete, it will have a serious effect on human bodies such as workers. For this reason, the gas shut-off valve 16 has a structure capable of obtaining a high degree of gas sealing.

A valve shaft 17 is rotatably provided above the one side X so as to penetrate both side walls, and a valve body 19 is fixed to the valve shaft 17 via an arm 18.
FIG. 7 shows the cross-sectional structure of the valve element 19, and the valve element 1
9, a flange portion 21 is provided on the outer periphery of the front surface of the metal body 20, and a heat-resistant cloth 23 having an appropriate thickness is disposed in a concave portion 22 inside the flange portion 21.
It is fixed to the metal body 20 by fixing means 24 composed of a nut. As the heat-resistant cloth 23, a material made of ceramic fiber or the like is usually used, and particularly, a material made of ceramic fiber containing alumina and silica as main components is most preferable in terms of heat resistance. In this embodiment, the entire inside of the concave portion 22 is not made to be a heat-resistant cloth for the purpose of cost reduction, and the asbestos layer 25 is provided inside the heat-resistant cloth 23. On the other hand, an inner tube 26 is fitted inside the inlet 100, and the tip of the inner tube 26 protrudes into the gas flow path by an appropriate length.

A counterweight 28 is attached to one end of the valve shaft 17 protruding outside the machine via an arm 27. When the shut-off valve is closed, the counterweight 28 is attached.
To secure the surface pressure at the seal portion. During normal operation, the gas shut-off valve 16 is retracted to a position shown by a virtual line in FIG. 5, and therefore, as shown in FIG. An arm 29 having an insertion hole 30 and extending in a direction opposite to the arm 27 is provided, and a pin locking hole 31 is provided on the gas cooler main body 1 side, and a fixing pin is provided in the pin insertion hole 30 and the pin locking hole 31. By inserting 32, the gas shut-off valve 16 can be kept open against the action of the counterweight 28.

The valve shaft 17 and the arm 18 also have a fluid cooling structure having a coolant passage a for cooling water or the like therein. A supply pipe 34 and a discharge pipe 35 for the refrigerant are connected to each end of the valve shaft 17, and a refrigerant flow path a in the valve shaft 17 and a refrigerant flow path a in the arm 18 are communicated by a communication pipe 36. I have.

In the other drawings, reference numeral 33 denotes an opening / closing lid for taking out the dust receiving bucket 11 outside the apparatus when collecting dust, and 37 denotes an exhaust gas conduit connected to the inlet 100 and the outlet 101, respectively. Also in this embodiment, as a structure for collecting dust, a structure including a hopper-shaped dust reservoir, an on-off valve and the like can be adopted as shown in FIG.

FIGS. 8 and 9 show an example in which a driving device 6 (cylinder device) is used for the moving mechanism 4. A plurality of slide shafts 5 extending outside the machine are connected by a connecting plate 38. The connecting plate 38 is connected to a rod of a cylinder device as the driving device 6. Other configurations are the same as those of the above-described embodiment, and therefore, are denoted by the same reference numerals and description thereof will be omitted.

According to the gas cooler having the structure as shown in FIGS. 3 to 7 or FIGS. 8 and 9, the exhaust gas discharged from the CVD equipment is supplied from the inlet 100 to the U-shaped gas in the machine. A part of the dust in the exhaust gas is introduced into the upper part on one side X side of the flow path and passes through the U-shaped bottom Z of the gas flow path, and falls down to accumulate in the dust receiving bucket 11. The exhaust gas is cooled in the process of passing through the cooling pipe group A on the other side Y of the U-shape, is discharged from the discharge port 101, and is sent to the dust collector side. During normal operation, the dust removal plate 3
Is retracted to the position shown in FIG. 4 or FIG. The gas cooler is operated for a certain period of time, and when dust adheres to the cooling pipe group A to a certain extent, the slide shaft 5 constituting the moving mechanism 4 is driven (in FIGS. 8 and 9, the drive shaft 6 drives the slide shaft 5). ) The dust removing plates 3a to 3e are slid in the cooling pipe direction (horizontal direction). Each cooling pipe 2 has an insertion hole 3 for dust removing plates 3a to 3e.
Since the dust removing plates 3a to 3e are inserted into or loosely inserted into 00, dust adhering to the surface of the cooling pipe 2 is removed. The dust that has been dropped falls into the dust receiving bucket 11 below the cooler, and when an appropriate amount of dust has accumulated, the inlet 100 is temporarily closed by the gas shutoff valve 16 and the opening / closing lid 33 is opened. The dust receiving bucket 11 is taken out of the machine and the dust is collected.

The gas shut-off valve 16 has a high degree of sealing because the heat-resistant cloth 23 is pressed against the tip of the inner tube 26 attached to the inlet 100 by the action of the counterweight 28. In addition, by using a ceramic fiber material as the heat-resistant cloth 23 in particular, high-temperature exhaust gas such as SiCl ₄ discharged from a CVD facility can also be used.
Long-term durability is obtained.

FIG. 10 shows a C for manufacturing a high silicon steel sheet to which the gas cooler of FIGS. 3 to 7 or 8 and 9 is applied.
It shows an exhaust gas processing flow of the VD processing equipment. In the figure, reference numeral 40 denotes a continuous processing furnace, which includes a heating zone 42 and a CV.
It is composed of a D zone 43, a solitary zone 44, and a cooling zone 45. The exhaust gas treatment system 41 cools, collects dust, and collects the exhaust gas discharged from the CVD zone 43. From the upstream side, the gas cooler 46, the dust collector 47 (bag filter), and the exhaust gas treatment device 48 of the present invention are provided. And suction blower 49
It has. In this flow, the gas cooler 46 of the present invention is provided in each of the two exhaust gas conduits 37 arranged in parallel.

[0029]

According to the gas cooler of the present invention described above, dust adhering to the cooling pipe can be easily removed even during the operation of the siliconizing treatment in the CVD equipment , and the adhesion and growth of dust in the cooling pipe can be achieved. And stable operation can be performed for a long period of time.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of a gas cooler of the present invention.

FIG. 2 is a cross-sectional view of the gas cooler shown in the embodiment of FIG. 1 along the line II-II.

FIG. 3 is a longitudinal sectional view showing another embodiment of the gas cooler of the present invention.

FIG. 4 is a partially cutaway side view of the gas cooler shown in FIG. 3;

5 is a cross-sectional view of the gas cooler shown in the embodiment of FIG. 3 along the line VV.

FIG. 6 is a partial cross-sectional plan view partially showing a counter weight of the gas cooler shown in the embodiment of FIG. 3 and its periphery;

FIG. 7 is a longitudinal sectional view of a gas shut-off valve of the gas cooler shown in the embodiment of FIG.

FIG. 8 is a partially cutaway side view showing another embodiment of the gas cooler of the present invention.

9 is a horizontal sectional view partially showing a cooling pipe portion of the gas cooler shown in the embodiment of FIG. 8;

FIG. 10 is an explanatory diagram showing an exhaust gas processing flow of the CVD processing equipment to which the gas cooler of the present invention is applied.

[Brief description of reference numerals]

1: Gas cooler body, 2: Cooling pipe, 3, 3a to 3e
... Dust removal plate, 4 ... Movement mechanism, 5 ... Slide axis,
6: drive mechanism, 300: insertion hole, A: cooling pipe group

Claims (1)

(57) [Scope of request for utility model registration] 1. A CVD equipment for performing a siliconizing treatment of a steel sheet.
Exhaust gas containing SiCl ₄ and FeCl ₂ discharged from coal
A gas cooler for cooling an air conditioner, which has a number of cooling pipes arranged in parallel in the airframe, and exhaust gas is provided between these cooling pipes.
A gas cooler that performs gas cooling by passing through a cooling pipe has a plurality of insertion holes into which a cooling pipe can be slidably inserted or loosely inserted. There consists of a dust brushing plate mounted in the fitted or loosely fitted interpolated so, a moving mechanism for moving the dust brushing plate to the tube axis direction of the cooling pipe, solidified by cooling the exhaust gas
The FeCl ₂ dust adhering to the cooling pipe surface
Dust removal to remove by moving the removal plate
A gas cooler having a mechanism .