JP2011000590A - Filter device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a filter device capable of removing fine particles contained in an exhaust gas, the particles having larger particle size to smaller particle size, in proportion to a speed of the exhaust gas.SOLUTION: The filter device includes: a casing 2 having an inlet 6 and an outlet 8; a diaphragm 3 arranged in the casing 2 so as to have a plurality of spiral parts to form a spiral flow path 11; and a filter member 4 arranged on at least one surface of the diaphragm 3, wherein the flow path width (A) of the spiral part 3a located on the outermost side of the spiral flow path 11 is made wider than the flow path width (B) of the spiral part 3b located on the inner side than the outermost side of the spiral flow path 11, and the fine particles contained in the exhaust gas are made to have a larger linear speed on the spiral part located on the inner side than on the spiral part located on the outer side of the spiral flow path.

Description

  The present invention relates to a filter device that is disposed in, for example, a semiconductor manufacturing process or a liquid crystal manufacturing process, and removes fine particles such as reaction products contained in exhaust gas or collects mist contained in a liquid.

  Various methods including an ion implantation method, a metal etching method such as aluminum, and a CVD method are employed in the semiconductor manufacturing process, but in any semiconductor manufacturing process employing any method, hydrofluoric acid, silane gas, Exhaust gas containing harmful gases such as tetraethoxysilane and ammonia, impurities such as reaction products, and other fine particles such as mist and dust is generated. It has been found that the amount of fine particles mixed in the exhaust gas is particularly large in a CVD semiconductor manufacturing process.

Therefore, a detoxification facility for removing fine particles mixed in the exhaust gas is arranged in the semiconductor manufacturing process.
Conventional abatement equipment removes fine particles contained in exhaust gas by adsorbing them on an adsorbent such as ion exchange resin or zeolite, adsorbing them in water with a water scrubber, or decomposing them by combustion with a burner. .

  When removing particulates in the exhaust gas, there is a problem that the pressure loss per unit area of the adsorbent increases due to the adsorbed particulates in the abatement equipment using the adsorbent. Since the liquid becomes sludge due to fine particles, there is a problem that a sludge treatment is necessary, and in the abatement equipment by combustion, there is a problem that the nozzle of the burner is clogged or the combustion chamber becomes dirty.

  The present applicant arranges the pretreatment device upstream of the abatement equipment arranged in the semiconductor manufacturing process, so that even if a large amount of fine particles are contained in the exhaust gas of the semiconductor manufacturing process, the abatement equipment Has been developed (for example, see Patent Document 1).

The filter device includes a casing having an inlet and an outlet, a partition wall disposed in the casing so as to form a continuous spiral channel having a plurality of spiral portions, and a filter member disposed on at least one surface of the partition wall When the exhaust gas introduced into the casing travels along the spiral flow path, the fine particles contained in the exhaust gas are removed by the filter member disposed in the spiral flow path, and the fine particles are removed. Exhaust gas is sent from the outlet to the abatement equipment.
JP 2001-149723 A (page 3, FIG. 3)

  In the above filter device, the flow path width of the spiral portion of the spiral flow path is set to the same dimension from the outer end to the inner end, so that the exhaust gas flowing through the spiral flow path has a linear velocity of the spiral flow. The particle is contained in the exhaust gas from the particle having a large particle size to the particle having a small particle size in proportion to the exhaust gas velocity.

  The present invention has been made in consideration of the above-mentioned points, and by reducing the linear velocity of the exhaust gas flowing through the spiral flow path at the outer spiral portion and at the inner spiral portion, the particulates contained in the exhaust gas are reduced. It is an object of the present invention to provide a filter device capable of removing particles having a large particle size from particles having a small particle size in proportion to the exhaust gas velocity.

  The filter device of the present invention has a casing having an inlet and an outlet, a partition wall disposed in the casing so as to form a continuous spiral channel having a plurality of spiral portions, and disposed on at least one surface of the partition wall. And a filter device in which exhaust gas containing fine particles of various sizes is introduced from the inlet, the flow path width of the spiral portion located on the outer end side of the spiral flow path is inside the filter device And the fine particles contained in the exhaust gas have a larger linear velocity in the spiral portion located inside than the spiral portion located outside the spiral flow passage. It is characterized by doing so.

  Moreover, the filter apparatus of this invention can make a whole structure compact by arrange | positioning a cylindrical filter in the inner space of a partition.

  In the filter device of the present invention, since the exhaust gas flowing through the spiral flow path has a low linear velocity of the outer spiral part and a high linear velocity of the inner spiral part, particles having a large particle diameter contained in the exhaust gas are removed from the spiral flow path. By capturing particles with a small particle size at the inner part of the spiral flow path, particles contained in the exhaust gas are collected from particles having a large particle size in proportion to the exhaust gas velocity. Even small particles can be removed.

It is a longitudinal cross-sectional view of the filter apparatus of preferable embodiment of this invention. It is sectional drawing along line AA of FIG. It is a figure which shows other embodiment of the filter apparatus by this invention.

Hereinafter, a filter device of the present invention will be described in detail with reference to the drawings.
As shown in FIGS. 1 and 2, the filter device 1 of the present invention includes a cylindrical casing 2, a spiral partition 3 disposed inside the cylindrical casing 2, and an inner surface of the cylindrical casing 2 and the partition 3. It has the filter member 4 arrange | positioned and the cylindrical filter 5 arrange | positioned in the center part of the partition 3. FIG.

  As shown in FIG. 1, the cylindrical casing 2 has a cylindrical casing body 7 having an upper end opening with an inlet 6 provided on the upper side of a side wall 7a, and an opening end of the cylindrical casing body 7 having an outlet 8 in the center. The lid 9 is fixed to the head. A cylindrical filter 5 is attached to the lower surface of the lid 9 by a fixing means 10 corresponding to the outlet 8.

  As shown in FIG. 2, the spiral partition 3 has three spiral portions 3a, 3b, and 3c. The height of the spiral partition 3 substantially matches the height of the cylindrical casing body 7. When the spiral partition wall 3 is arranged inside the cylindrical casing 2, it forms a spiral channel 11 that continuously extends from the outside to the inside inside the cylindrical casing 2. It is preferable that the surface of the spiral partition wall 3 is an uneven surface or a baffle plate is provided on the spiral partition wall 3.

  Of the spiral flow channel 11, the spiral flow channel 11a formed between the inner wall 2a of the cylindrical casing 2 and the spiral portion 3a located on the outermost side has a flow width A and the spiral portion 3a. It is set wider than the channel width B of the channel 11b formed between the spiral part 3b located on the inner side. Similarly, the channel width B of the channel 11b formed between the spiral part 3a and the spiral part 3b in the spiral channel 11 is the spiral part 3b and the spiral part 3c located inside the spiral part 3b. Is set wider than the channel width C of the channel 11c formed between the two. That is, the spiral flow passage 11 has a flow passage width that narrows sequentially from the outside to the inside in the direction of travel of exhaust gas.

  In the above embodiment, the spiral partition 3 forming the spiral channel 11 is formed by three spiral portions, but the number of spiral portions can be increased or decreased as necessary. When the number of spiral parts is six or more, the flow path widths of the plurality of flow paths including the innermost flow path can be the same.

  The filter member 4 is a thin plate-shaped molded product formed of a fiber material having excellent heat resistance and chemical resistance, and is disposed in the direction of the spiral flow path 11 along the inner surface of the spiral partition 3. The filter member 4 can also be disposed on both sides of the spiral partition 3. The said filter member 4 is effective in collection | recovery of powder, liquid, or liquid mist by shape | molding with a magnet fiber.

  Similar to the filter member 4, the cylindrical filter 5 is formed of a fiber material having excellent heat resistance and chemical resistance. The cylindrical filter 5 is disposed at the center of the partition wall 3. The cylindrical filter 5 removes fine particles having a particularly small particle diameter that cannot be sufficiently removed by the filter member 4. The cylindrical filter 5 can be formed of a mixture of a fiber material and a metal material, or may be formed of only a metal material.

  Further, as a countermeasure to the case where the temperature of the exhaust gas is high, the cooling jacket 12 can be disposed so as to surround the outer surface of the cylindrical casing 2 in order to cool the exhaust gas. The cooling jacket 12 is a means that can hold or circulate a target refrigerant for cooling the filter device 1. The refrigerant is not particularly limited, but water is usually used.

Next, the operation will be described.
The filter device 1 of the present invention is disposed on the upstream side of an abatement facility for a semiconductor manufacturing process (not shown) and is a contaminant such as a reaction product in exhaust gas that is a gas to be processed discharged from a processing device for the semiconductor manufacturing process. It is used to remove other fine particles including mist and dust.

  Exhaust gas discharged from the semiconductor manufacturing process is introduced from the inlet 6 of the filter device 1 into the spiral flow path 11 disposed in the cylindrical casing 2 through a pipe (not shown). In the spiral channel 11, the channel width A of the outermost channel 11a is set wider than the channel width B of the inner channel 11b adjacent to the spiral channel 11, so that the exhaust gas traveling through the spiral channel 11 is the outermost channel. The linear velocity of the outer channel 11a is slower than the linear velocity of the inner channel 11b inside. Therefore, particles having a large particle size among the fine particles contained in the exhaust gas collide with the filter member 4 disposed on the inner surface of the cylindrical casing 2 by the action of a centrifugal force proportional to the speed of the exhaust gas. The fine particles colliding with the filter member 4 on the inner surface of the cylindrical casing 2 adhere to the filter member 4 or fall due to the action of gravity and are collected in the cylindrical casing 2.

  Similarly, since the exhaust gas that has passed through the outermost flow channel 11a of the spiral flow channel 11 has a linear velocity of the inner flow channel 11b of the exhaust gas that is slower than the linear velocity of the inner flow channel 11c inside, the particle diameter is the same. Large particles collide with the filter member 4 disposed on the inner surface of the spiral partition 3 by the action of centrifugal force proportional to the speed of the gas to be treated, and the fine particles colliding with the filter member 4 adhere to the filter member or fall. And collected in the cylindrical casing 2.

  The exhaust gas that has passed through the inner flow path 11b of the spiral flow path 11 collides with the filter member 4 disposed on the inner surface of the spiral partition wall 3 by the action of centrifugal force, and the fine particles that have collided with the filter member 4 are filtered out. It adheres to or falls and is collected in the cylindrical casing 2.

In this way, the fine particles contained in the exhaust gas are removed from particles having a large particle size to particles having a small particle size in proportion to the speed of the exhaust gas when traveling inward in the radial direction along the spiral flow path 11. Is done. Fine particles having a small particle diameter that have not been removed in the spiral flow path 11 are removed by the cylindrical filter 5 disposed in the center of the partition wall 3.
The exhaust gas from which the fine particles have been removed in the filter device 1 is guided from the outlet 8 of the filter device 1 to a detoxification facility through a pipe (not shown).

  FIG. 3 shows another embodiment of the present invention. Compared with the filter device 1 shown in FIG. 1, the filter device 20 shown in FIG. 3 has a partition wall 3 lower in height than the cylindrical casing 21 and forms a space 22 above the cylindrical filter 5. The only difference is that a donut-shaped element 23 formed of a stainless steel mesh is disposed. The exhaust gas that has passed through the cylindrical filter 5 directly collides with the donut-shaped element 23, and then passes through a gap between the baffle plate 24 attached to the lower surface of the lid 9 and the cylindrical casing 21 and is guided to the outlet 8. . Thereby, the fine particles contained in the exhaust gas are more effectively removed.

  In addition, although the said embodiment demonstrated removing the microparticles | fine-particles contained in exhaust gas with the filter apparatus 1, it can utilize in order to collect | recover liquids and collect | recover mist contained in liquids.

  By incorporating the filter device of the present invention into an exhaust gas line such as a semiconductor manufacturing process, the load on the abatement equipment can be reduced, and the number of cleanings of the abatement equipment and the equipment life can be greatly improved.

DESCRIPTION OF SYMBOLS 1 Filter apparatus 2 Casing 3 Spiral partition 4 Filter member 11 Spiral flow path A Channel width B Channel width C Channel width

Claims (5)

  A casing having an inlet and an outlet; a partition wall disposed in the casing so as to form a continuous spiral channel having a plurality of spiral portions; and a filter member disposed on at least one surface of the partition wall; In the filter device in which exhaust gas containing fine particles of various sizes is introduced from the inlet, the flow width of the spiral portion located on the outer end side of the spiral flow passage is set to the flow of the spiral portion located inside the spiral portion. It is wider than the passage width, and fine particles contained in the exhaust gas have a larger linear velocity in the spiral portion located inside than the spiral portion located outside the spiral flow path. Filter device to do.   2. The filter device according to claim 1, wherein the spiral flow path has a flow path width of the spiral portion that is gradually reduced from the outside to the inside.   The filter device according to claim 1, wherein a cylindrical filter is disposed in a space formed inside the partition wall.   The filter device according to any one of claims 1 to 3, wherein a baffle plate is attached to the lower surface of the lid, and a donut-shaped element is disposed in an upper space of the cylindrical filter.   The filter device according to any one of claims 1 to 4, wherein a cooling water jacket is disposed on an outer surface of the casing.

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