JP2012240042A - High temperature air filter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high temperature air filter with a structure where filter media having a collecting function are folded in the form of zigzag, a separator is sandwiched between the folded media with the entire circumference airtightly attached with sealants such as adhesives not to allow the air to leak to secure airtightness between the end faces of the filter media folded in the zigzag form and upper and lower filter frames.SOLUTION: The high temperature air filter including the filter media with inorganic binders principally composed of a glass fiber, fixing the upper and lower faces of the filter media sandwiching separators between the filter media folded in the zigzag form to the upper and lower plates of the filter frames through packing materials and the sealants provided inside the lower and upper plates of the filter frames consisting of a left side plate, a right side plate, a lower plate, and an upper plate, and airtightly attaching the right/left ends of the filter media with a silicone adhesive coated to an inside surface of the left side plate and the right side plate, wherein the combinations of the packing material, a sealant, and a separator are selected in accordance with the temperatures of the air which passes through the filter media, is provided.

Description

  The present invention relates to a high temperature air filter for air cleaning used in semiconductor manufacturing industry, pharmaceutical industry, food and the like.

  In recent years, clean ovens and dryers for drying articles with high-temperature clean air have high-temperature air filters for cleaning the introduced air, and also include processes such as drying and firing during the manufacture of flat panel displays, or special RI and incinerators. High temperature air filters for cleaning air attached to exhaust gas and the like have been arranged. In addition, there is a need to clean the introduced air even in processes that require higher temperatures, such as film formation during flat panel display manufacturing and fine pattern formation, and there is a need for high-temperature air filters with higher heat resistance. .

  In general, air filters used at room temperature fold a filter medium with a trapping function in a zigzag shape, and use a sealant such as adhesive to prevent air leakage by sandwiching a separator between the folded filter medium. It has an airtight structure.

  However, because the high temperature air filter uses conventional room temperature type filter media and seal materials, when high-temperature air touches the filter media, the organic binder in the filter media carbonizes, and the carbide on the air outflow side surface generates dust. There are problems such as inconvenience of scattering and cracks in the sealing material to cause air leakage.

  Therefore, the air filter for high temperature uses a filter medium mainly composed of glass fiber and an inorganic binder, and the filter medium is airtightly attached through a heat-resistant adhesive sealing material such as silicone resin in a filter frame such as stainless steel. Structure is considered.

However, due to the difference in coefficient of thermal expansion between the sealing material and the filter frame, peeling occurs between the end face of the filter medium folded in zigzag and the upper and lower filter frames, or cracks occur, resulting in damage to airtightness. There was a problem that air leakage occurred.

  Therefore, a double sealing method using a fiber packing such as glass cotton and a heat resistant adhesive seal material between the end face of the filter medium folded in a zigzag shape and the upper and lower filter frames is considered.

  However, these double sealing methods also cause cracks in the seal part due to the difference in thermal expansion coefficient between the filter frame and the sealing material at high temperatures, resulting in a decrease in air filter collection efficiency or damage to the filter medium itself. There was a problem of being connected.

  Therefore, the present invention is intended to solve these problems.

  The first object of the present invention is to maintain stable collection efficiency even with respect to temperature changes of air passing through a filter medium.

The second object of the present invention is to damage the airtightness by causing separation or cracking between the end face of the filter medium folded in a zigzag manner against the high temperature gas and the upper and lower filter frames. The air leakage is prevented from occurring.

The third object of the present invention is to stably maintain a high collection efficiency over a long period of time without causing gas leakage or destruction of the filter medium.

A fourth object of the present invention is to provide a high-temperature air filter that generates a small amount of outgas during ventilation and has a low pressure loss.

  The first solution of the present invention uses a filter medium mainly composed of glass fiber and using an inorganic binder, and is provided on the lower plate of the filter frame composed of the left side plate, the right side plate, the lower plate, and the upper plate, and on the inner surface of the upper plate. The upper and lower ends of the filter media with the separator sandwiched between zigzag-shaped filter media were fixed to the upper and lower plates of the filter frame, and applied to the inner surfaces of the left and right plates via a packing material and a seal material. In a high-temperature air filter in which the left and right ends of a filter medium are hermetically attached with a silicon adhesive, a combination of a packing material, a seal material, and a separator is selected according to the air temperature passing through the filter medium.

  In the second solution of the present invention, when the temperature of air passing through the filter medium is 250 ° C., the packing material is a glass fiber sheet, the sealing material is an epoxy adhesive, and the separator is aluminum.

  The third solving means of the present invention is such that when the temperature of air passing through the filter medium is 500 ° C., the packing material is a ceramic fiber sheet, the sealing material is a ceramic adhesive, and the separator is heat resistant SUS.

  The fourth solving means of the present invention is that the left and right side plates of the filter frame are flat plates, and the opposite end portions are outward L-shaped and the other opposite end portions are inner L-shaped tip portions. The outer and L-shaped reinforcing pieces are flat, the upper plate and the lower plate are flat plates, and the opposite ends are inward L-shaped and the other opposite ends are left and right ribs. The tongue piece is in contact with the piece.

  Here, the filter medium has a structure in which glass fibers obtained by mixing glass fibers are bonded with an inorganic binder. The filter medium preferably has a thickness of 200 to 900 μm.

  Examples of the inorganic binder include silica, talc, kaolin mineral, bentonite (including active bentonite), diatomaceous earth, alumina (including active alumina), a mixture of silica and alumina, aluminum silicate, hydrous magnesium silicate having a ribbon-like structure, and An inorganic substance consisting of at least one selected from the group of synthetic zeolites can be used. In particular, the inorganic binder is preferably silica using organosilane and organosiloxane which is a hydrolytic condensate of the organosilane as a raw material. Examples of the organosilane include tetrachlorosilane, trichlorosilane, methyltrichlorosilane, tetramethylsilane, tetraethylsilane, tetrapropylsilane, tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, trimethoxysilane, triethoxysilane, and tetrapropyl. Examples include silazane, methyltrimethoxysilane, ethyltrimethoxysilane, methyltriethoxysilane, propyltrimethoxysilane, phenyltrimethoxysilane, and vinyltrimethoxysilane.

  And since the inorganic binder made of silica has high bondability to glass fibers and the strength of the bonding film itself formed between the glass fibers, the strength of the obtained filter medium is improved even if the amount of silica added is reduced. In addition, the pleatability of the filter medium can be improved. In addition, the said silica is used as a solution of alcohol like methyl alcohol in manufacture of the filter medium mentioned later.

  The packing material spread on the upper and lower plates of the filter frame is preferably a sheet of glass fiber, ceramic fiber or the like.

  The sealing material applied on the packing material is preferably an epoxy adhesive or a ceramic adhesive.

  Aluminum, stainless steel, etc. are used for the separator inserted between the filter media.

  The operation of the above problem solving means is as follows. That is, the packing material is spread on the upper and lower plates of the filter frame, the sealing material is preliminarily applied on the packing material, the filter material is zigzag-folded through the sealing material, the lower end surface and the filter frame. Since the plate and lower plate are fixed, due to the difference in coefficient of thermal expansion, separation occurs between the end face of the filter medium folded in a zigzag shape and the upper and lower filter frames, and cracks occur, resulting in airtightness. There is no problem of damaging the air and causing air leakage, and a predetermined collection function can be maintained indefinitely.

  Furthermore, the filter medium constituting the high-temperature air filter is made of glass fiber using an inorganic binder that can withstand high temperatures, the filter frame is made of a metal frame that can withstand high temperatures, the sealing material is made of material that can withstand high temperatures, and the pleats between the filter media Since the separator interposed between them is made of a material that can withstand high temperatures, the fibers of the filter medium are not scattered by the passing high-temperature air and the filter cloth is not broken, and the predetermined collection function can be maintained forever.

  In addition, since the binder added to the glass fiber is not a material that causes clogging, and the amount added is also suitable for the material, a high-temperature air filter with low pressure loss can be provided.

(1) Since the lower end surface is sealed on the filter medium with the sealing material applied on the packing material, the packing material also serves as a cushion material for deformation due to the difference in thermal expansion coefficient. Can be effectively prevented, and the sealing performance can be improved.
(2) Since the packing material is in contact with the upper and lower filter frame end faces, even if the metallic filter frame expands and contracts due to the atmospheric temperature, the sealing performance does not deteriorate.
(3) Further, since the packing material is in contact with the upper and lower filter frame end faces, it can absorb the impact received during transportation, etc., thereby protecting the sealing material from the impact and maintaining a good adhesive state. it can.
(4) Even if the separator interposed between the filter media receives heat and extends in the direction of the upper and lower end surfaces of the filter media, the packing material absorbs the elongation, and damage to the filter media and the seal material can be prevented.
(5) The filter medium can be stably held for a long period of time, and a good high-temperature air filter function can be achieved.
(6) Even when a high-temperature air filter is used in a dryer such as a clean oven, high-temperature clean air can be introduced without generating dust.
(4) The filter medium of the high-temperature air filter of the present invention is superior to the conventional one in that the filter medium strength is improved by fixing the fiber with an inorganic binder, and the low pressure loss and the high collection efficiency are achieved.

The perspective view which shows the high temperature air filter of this invention which notched one part. A-A 'sectional drawing. Part diagram of filter frame

  Hereinafter, a high temperature air filter according to an embodiment of the present invention will be described with reference to the accompanying drawings.

  In the figure, reference numeral 1 denotes a filter frame. The filter frame 1 has a fiber diameter of 0.3 to 50 μm and a thickness of 0.1 to 1.0 mm with a separator 4 interposed between a packing material 2 and a seal material 3. A zigzag filter medium 5 made of glass fibers of mm, synthetic fiber, natural fiber or the like is attached.

  The filter frame 1 includes a left side plate 6, a right side plate 7, a lower plate 8, and an upper plate 9. The upper plate 8 and the lower plate 9 are flat plates 13 and tongue pieces 14 with opposite end portions being inward L-shaped. It is comprised with the flat plate which consists of. And the collar piece 10 and the tongue piece 14 become a shape which contact | abuts, and when it contact | abuts, the hole formed in each corresponds.

  Next, the manufacturing method of the high temperature air filter of this invention is demonstrated.

  First, a nonwoven fabric or woven fabric made of glass fibers, synthetic fibers or natural fibers having a fiber diameter of 0.3 to 50 μm and a thickness of 0.1 to 1.0 mm is combined with an organic binder or an inorganic binder to be integrated. The filter medium 5 is formed.

  Next, the packing material 2 is spread on the lower plate 8, and a sealing material is applied to the gutter.

  Then, the lower end surface of the zigzag filter medium is immersed in the sealing material 3 and dried and cured.

  In this way, after fixing the filter medium 5 arranged in a zigzag shape to the sealing material, the collar piece 10 'of the left side plate 6 and the right side plate 7 is brought into contact with the tongue piece 14 of the lower plate 8, and the holes formed respectively After matching, fix with bolts. At that time, a silicon adhesive is applied to the inner surfaces of the left side plate 6 and the right side plate 7, and both ends of the filter medium are sealed and fixed.

  After fixing the left side plate 6 and the right side plate 7 to the lower plate 8, the left side plate 6 and the right side plate 7 are held, the filter medium 5 is turned upside down, and placed in advance on the packing material 2 laid down inside the upper plate 9. The lower end surface of the filter medium 5 is immersed in the applied sealing material 3 and dried and cured.

  At this time, the flange pieces 10 of the left side plate 6 and the right side plate 7 are brought into contact with the tongue pieces 14 of the lower plate 8, the holes formed in the respective plates are matched, and then fixed with bolts. This completes the high temperature air filter.

Next, specific examples will be described.

When the temperature of the air passing through the filter medium 5 is 250 ° C., the combination of the packing material, the sealing material, and the separator is as follows.
Packing material: Glass fiber sheet sealing material: Epoxy adhesive separator: Aluminum

When the temperature of the air passing through the filter medium is 500 ° C., the combination of the packing material and the adhesive is as follows.
Packing material: Ceramic fiber sheet sealing material: Ceramic adhesive separator: Heat resistant SUS

  Note that the present invention is not limited to the above-described embodiments as they are, and can be embodied by modifying the components without departing from the scope of the invention in the implementation stage, and a plurality of components disclosed in the embodiments. Various modifications can be made by an appropriate combination of the above.

  The high-temperature air filter described in the present invention may be a high-performance filter, ultra-high-performance filter (ULPA), a medium-performance filter, a pre-filter, or a pocket-type filter. However, the gist of the present invention is not changed.

  The high-temperature air filter of the present invention, which can be used stably over a long period of time without the generation of particulate matter, gas generation, or fiber scattering even in a high temperature range, is used for circulating air cleaning or incinerators such as clean ovens and dryers. It is optimal and useful for exhaust gas treatment.

DESCRIPTION OF SYMBOLS 1 ... Filter frame 2 ... Packing material 3 ... Sealing material 4 ... Separator 5 ... Filter material 6 ... Left side plate 7 ... Right side plate 8 ... Lower plate 9 ... Upper plate 10 ... collar piece 11 ... tip 11 11 ... reinforcing piece 13 ... dripping piece 14 ... tongue piece

Claims (3)

  Using a filter medium mainly composed of glass fiber and using an inorganic binder, the left side plate, the right side plate, the lower plate, the lower plate of the filter frame composed of the upper plate, the packing material and the sealing material provided on the inner surface of the upper plate, The upper and lower ends of the filter medium with the separator sandwiched between the zigzag-shaped filter medium are fixed to the upper and lower plates of the filter frame, and the left and right ends of the filter medium are attached to the inner surface of the left and right plates with silicon adhesive. A high-temperature air filter, wherein a combination of a packing material, a sealing material, and a separator is selected in accordance with the temperature of air passing through a filter medium.   2. The high temperature air filter according to claim 1, wherein when the temperature of the air passing through the filter medium is 250 ° C., the packing material is a glass fiber sheet, the sealing material is an epoxy adhesive, and the separator is aluminum.   2. The high temperature air filter according to claim 1, wherein when the temperature of the air passing through the filter medium is 500 ° C., the packing material is a ceramic fiber sheet, the sealing material is a ceramic adhesive, and the separator is heat resistant SUS.

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