Filter device

Abstract

To inhibit foreign objects originating from exhaust gas from adhering to the interior of a pipe.SOLUTION: A filter device 60 for removing foreign matters included in an exhaust gas comprises: a housing 64; a filter unit 72 housed in the housing 64; and an outlet unit 30 which connects the housing 64 with the subsequent pipe 82 and causes the exhaust gas that has passed through the filter unit 72 to flow to the pipe 82. The outlet unit 30 forms a vortex swirl flow flowing in a helical shape from the upstream side of exhaust gas flow to the downstream side along an inner surface of the outlet unit 30 by a heat gas introduced into the outlet unit 30.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to a filter device. [Background technology]

[0002] Exhaust gases generated in semiconductor manufacturing processes and liquid crystal manufacturing processes contain components harmful to the human body. For example, various methods including ion implantation, metal etching of aluminum and the like, and CVD are used in semiconductor manufacturing processes. In any of the semiconductor manufacturing processes that use such methods, exhaust gases are generated that contain a mixture of harmful gases such as hydrofluoric acid, silane gas, tetraethoxysilane, and ammonia, impurities such as reaction products, and other fine particles such as mist and dust. For this reason, in semiconductor manufacturing processes and liquid crystal manufacturing processes, abatement equipment is used to remove the fine particles mixed in the exhaust gas. For example, Patent Document 1 discloses a filter device that can remove the fine particles contained in the exhaust gas. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2005-74362 A Summary of the Invention [Problem to be solved by the invention]

[0004] High-temperature exhaust gases generated in semiconductor manufacturing processes and liquid crystal manufacturing processes contain vaporized components (vaporized components). These vaporized components may not be sufficiently removed even with conventional filter devices. Conventional abatement facilities include a filter device and a downstream abatement device that are connected to each other through piping. Exhaust gas is sent to each device through the piping. At this time, the vaporized components in the exhaust gas may cool on the wall surface of the piping and condense or solidify (powder) to become foreign matter, which may adhere to the wall surface of the piping. Foreign matter adhering to the wall surface may cause the piping to become clogged. Therefore, in the past, it was necessary to periodically remove the piping and clean the inside of the piping.

[0005] The present invention has been made in consideration of the above points, and has an object to suppress adhesion of foreign matter resulting from exhaust gas to the inside of piping. [Means for solving the problem]

[0006] The filter device according to the present invention comprises: [1] A filter device for removing foreign matter contained in exhaust gas, A housing and A filter unit housed in the housing; and an outlet unit that connects the housing to a downstream pipe and causes the exhaust gas that has passed through the filter unit to flow into the pipe; The outlet unit is a filter device in which hot gas introduced into the outlet unit forms a vortex flow that flows spirally from the upstream side to the downstream side of the exhaust gas flow along the inner surface of the outlet unit.

[0007] The filter device according to the present invention comprises: [2] The outlet unit has a wall portion and a guide tube disposed inside the wall portion, The filter device according to [1], wherein a hot gas flow path through which the hot gas passes is formed between the wall portion and the guide tube.

[0008] The filter device according to the present invention comprises: [3] The filter device described in [2], wherein the guide pipe has an inclined portion extending toward the central axis as it approaches the downstream side, and a parallel portion connected to the downstream end of the inclined portion and extending parallel to the central axis.

[0009] The filter device according to the present invention comprises: [4] The outlet unit is a filter device as described in [2] or [3], having an inlet pipe for introducing the hot gas into the hot gas flow path and an opening in the wall portion through which the inlet pipe opens.

[0010] The filter device according to the present invention comprises: [5] The filter device according to [4], wherein the inlet pipe extends in a direction inclined relative to the radial direction at the opening. Effect of the Invention

[0011] According to the present invention, it is possible to suppress adhesion of foreign matter resulting from exhaust gas to the inside of a pipe. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a diagram for explaining one embodiment of the present invention, and is a diagram that generally illustrates an example of a harm control system including a filter device. [Diagram 2] FIG. 2 is a vertical cross-sectional view showing an example of a filter device. [Diagram 3] FIG. 3 is a cross-sectional view of the filter device corresponding to the line III-III in FIG. [Figure 4] FIG. 4 is a vertical cross-sectional view showing an example of an outlet unit of a filter device. [Diagram 5] FIG. 5 is a cross-sectional view of the outlet unit corresponding to line VV in FIG. [Figure 6] FIG. 6 is a schematic diagram showing a vortex swirling flow generated in the outlet unit. [Figure 7] FIG. 7 is a vertical sectional view showing a modified example of the filter device. [Figure 8] FIG. 8 is a vertical sectional view showing another modified example of the filter device. [Figure 9] FIG. 9 is a vertical sectional view showing still another modified example of the filter device. [Figure 10] FIG. 10 is a cross-sectional view of the filter device corresponding to the line XX in FIG. [Figure 11] FIG. 11 is a vertical sectional view showing still another modified example of the filter device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings attached to this specification, the scale and the aspect ratio may be appropriately changed and exaggerated from those of the actual objects for the convenience of illustration and ease of understanding.

[0014] In addition, terms used in this specification that specify shapes, geometric conditions, and the degree thereof, such as "parallel," "orthogonal," and "same," as well as values ​​of length and angle, are not to be bound by strict meanings, but are to be interpreted to include a range within which similar functions can be expected.

[0015] In this specification, the direction in which the central axis A of the outlet unit 30 extends (longitudinal direction) is defined as the axial direction da, the direction perpendicular to the axial direction da is defined as the radial direction dr, and the direction along the circumference around the central axis A is defined as the circumferential direction dc. In addition, along the radial direction dr, the side approaching the central axis A is defined as the inner side, and the side going away from the central axis A is defined as the outer side.

[0016] FIG. 1 is a diagram for explaining one embodiment of the present invention, and is a diagram that generally illustrates an example of an abatement system 10 including a filter device 60. As shown in FIG.

[0017] The abatement system 10 is a system that treats harmful components contained in exhaust gas discharged from a manufacturing apparatus 5 such as a semiconductor manufacturing apparatus or a liquid crystal manufacturing apparatus. The abatement system 10 of this embodiment includes a first filter device 61 (filter device 60), a vacuum pump 12, a second filter device 62 (filter device 60), and abatement device 14. The abatement system 10 of this embodiment includes two filter devices 60, the first filter device 61 and the second filter device 62, but is not limited to this, and the abatement system 10 may include only one filter device 60, or may include three or more filter devices 60. In FIG. 1, the flow of exhaust gas discharged from the manufacturing apparatus 5 is indicated by arrows.

[0018] The abatement system 10 includes pipes 20 to 24. The pipe 20 connects the production equipment 5 and a first filter device 61. The exhaust gas discharged from the production equipment 5 passes through the pipe 20 and heads toward the first filter device 61.

[0019] The pipe 21 connects the first filter device 61 and the vacuum pump 12. The exhaust gas discharged from the first filter device 61 passes through the pipe 21 and flows toward the vacuum pump 12.

[0020] The pipe 22 connects the vacuum pump 12 and the second filter device 62. The exhaust gas discharged from the vacuum pump 12 passes through the pipe 22 and flows toward the second filter device 62.

[0021] The pipe 22 connects the second filter device 62 and the detoxification device 14. The exhaust gas discharged from the second filter device 62 passes through the pipe 23 and heads toward the detoxification device 14.

[0022] One end of the pipe 24 is connected to the abatement device 14. The exhaust gas discharged from the abatement device 14 passes through the pipe 24 and heads to the outside of the abatement system 10.

[0023] The other end of the pipe 24 may be connected to another treatment device or to an exhaust passage for exhausting to the atmosphere.

[0024] The vacuum pump 12 has a function of sucking exhaust gas from the first filter device 61 and sending it to the second filter device 62. The vacuum pump 12 is not particularly limited, and various vacuum pumps can be used.

[0025] The detoxification device 14 is a device that further processes the exhaust gas from which particulates have been removed by the first filter device 61 and the second filter device 62, and removes remaining harmful components. As the detoxification device 14, various detoxification devices can be used without any particular limitation.

[0026] The first filter device 61 and the second filter device 62 are devices that remove at least a part of fine particles such as liquid fine particles and solid fine particles contained in exhaust gas. In this specification, when it is not necessary to distinguish the first filter device 61 and the second filter device 62 from each other, both the first filter device 61 and the second filter device 62 are simply called filter devices 60. In the filter device 60, at least a part of fine particles such as liquid fine particles and solid fine particles contained in the exhaust gas that flows into the filter device 60 from the first pipe 81 is removed. Thereafter, the exhaust gas flows out from the filter device 60 to the second pipe (subsequent pipe) 82. When the first filter device 61 is the filter device 60, the pipe 20 is the first pipe 81, and the pipe 21 is the second pipe 82. When the second filter device 62 is the filter device 60, the pipe 22 is the first pipe 81, and the pipe 23 is the second pipe 82.

[0027] FIG. 2 is a longitudinal sectional view showing an example of the filter device 60. FIG. 3 is a transverse sectional view of the filter device 60 corresponding to the line III-III in FIG. 2. The filter device 60 includes a housing 64, a filter unit 72, and an outlet unit 30. In the example shown in FIG. 2, the filter device 60 further includes a partition wall 74 and an impact plate 76. In the example shown in FIG. 2, the housing 64 includes a main body 66 and a lid 68. The main body 66 has a substantially cylindrical shape with a closed bottom, and houses the filter unit 72 therein. A first pipe 81 is connected to a lower portion of the side surface of the main body 66. This allows the inside of the first pipe 81 and the inside of the main body 66 to communicate with each other.

[0028] The lid portion 68 is a member that closes the upper portion of the main body portion 66. The lid portion 68 is detachably fixed to the main body portion 66, for example, by bolting. By removing the lid portion 68 from the main body portion 66, the filter unit 72 housed in the main body portion 66 can be replaced. The outlet unit 30 is connected to the lid portion 68. The lid portion 68 and the outlet unit 30 may be formed integrally with each other, or may be connected to each other by welding, bolting, or the like.

[0029] The filter unit 72 removes at least a part of fine particles such as liquid fine particles and solid fine particles contained in the exhaust gas flowing into the housing 64 from the first pipe 81. The specific configuration of the filter unit 72 is not particularly limited, and a known unit that functions as a filter unit may be used as appropriate. For example, the filter unit disclosed in JP 2005-74362 A may be used as the filter unit 72. In the example shown in Figs. 2 and 3, the filter unit 72 has a cylindrical shape, and the exhaust gas passes through the filter unit 72 from the outside to the inside in the radial direction of the filter unit 72, thereby removing at least a part of the fine particles contained in the exhaust gas. In Fig. 2, the flow of the exhaust gas is indicated by an outline arrow with a symbol E.

[0030] The partition wall 74 is a member for preventing exhaust gas that has flowed in from the first piping 81 and has not passed through the filter unit 72 from heading toward the second piping 82. A through hole is formed in the center of the partition wall 74, and the exhaust gas that has passed through the filter unit 72 heads toward the second piping 82 through this through hole.

[0031] The collision plate 76 is disposed between the through hole of the partition wall 74 and the second piping 82. The collision plate 76 is a member against which the exhaust gas that has passed through the through hole of the partition wall 74 is intended to collide. By the exhaust gas colliding with the collision plate 76, fine particles contained in the exhaust gas even after passing through the filter unit 72 are suppressed from moving toward the second piping 82.

[0032] High-temperature exhaust gases generated in semiconductor manufacturing processes and liquid crystal manufacturing processes contain vaporized components (vaporized components). Such vaporized components may not be sufficiently removed even with the filter unit 72. In this case, the vaporized components in the exhaust gas may cool on the wall surface of the downstream pipe connected to the filter device 60, condense or solidify (powder) and become foreign matter that may adhere to the wall surface of the pipe. The foreign matter that adheres to the wall surface may cause the pipe to become clogged.

[0033] In order to address such problems, the filter device 60 of this embodiment has an outlet unit 30 for suppressing adhesion of foreign matter to the wall surface of the subsequent piping (second piping) 82. The first filter device 61 has a first outlet unit 31, and the second filter device 62 has a second outlet unit 32. In this specification, when there is no need to distinguish the first outlet unit 31 and the second outlet unit 32 from each other, both the first outlet unit 31 and the second outlet unit 32 will be simply referred to as the outlet unit 30.

[0034] The outlet unit 30 of this embodiment will be described with reference to Fig. 4 and Fig. 5. Fig. 4 is a vertical cross-sectional view showing an example of the outlet unit 30, and Fig. 5 is a horizontal cross-sectional view of the outlet unit 30 corresponding to the line VV in Fig. 4.

[0035] In this embodiment, the first outlet unit 31 is connected to the first hot gas generator 28, and the second outlet unit 32 is connected to the second hot gas generator 29. In this specification, when it is not necessary to distinguish the first hot gas generator 28 and the second hot gas generator 29 from each other, the first hot gas generator 28 and the second hot gas generator 29 are simply referred to as the hot gas generator 27. The hot gas generator 27 is a device that generates high-temperature gas (hot gas). As the gas, for example, an inert gas such as nitrogen gas (N2 gas) can be used. In the hot gas generator 27, the inert gas is heated to a temperature of, for example, 200°C or more and 300°C or less. The heated inert gas (hot gas) is sent from the hot gas generator 27 to the outlet unit 30.

[0036] The outlet unit 30 has a function of causing the exhaust gas that has passed through the filter unit 72 of the filter device 60 to flow out to the second pipe 22. The exhaust gas discharged from the filter device 60 may be cooled by the wall of the subsequent pipe 82 while passing through the pipe 82. Vaporized components that have condensed or solidified in the cooled exhaust gas may adhere to the wall of the pipe 82. In this embodiment, hot gas generated by the hot gas generator 27 is injected into the outlet unit 30 to suppress a decrease in the temperature of the exhaust gas passing through the pipe 82.

[0037] The outlet unit 30 includes a wall portion 35, a guide pipe 40, and an introduction pipe 50. The wall portion 35 is a substantially cylindrical member forming an outer wall of the outlet unit 30. The wall portion 35 extends along the central axis A. A first opening 33 communicating with the inside of the housing 64 is formed at the upstream end of the outlet unit 30. A second opening 34 communicating with the subsequent piping (second piping) 82 is formed at the downstream end of the outlet unit 30. The exhaust gas flow E that has passed through the filter unit 72 flows into the outlet unit 30 through the first opening 33. The exhaust gas flow E that has passed through the outlet unit 30 flows out to the subsequent piping 82 through the second opening 34. The inner diameter of the wall portion 35 may be the same as the inner diameter of the piping 82. The wall portion 35 is formed of, for example, a metal. The overall length of the outlet unit 30 can be, for example, 30 mm or more and 300 mm or less. Preferably, the total length of the outlet unit 30 can be 50 mm or more and 200 mm or less. The inner diameter of the wall portion 35 can be, for example, 10 mm or more and 200 mm or less. Preferably, the inner diameter of the wall portion 35 can be 25 mm or more and 150 mm or less.

[0038] The guide tube 40 defines a hot gas flow path P H The guide tube 40 is a member for forming the heat gas flow path P. The guide tube 40 is a substantially cylindrical member disposed inside the wall portion 35. The guide tube 40 is formed of, for example, a metal. The thickness of the guide tube 40 may be smaller than the thickness of the wall portion 35. The central axis of the guide tube 40 coincides with the central axis A of the wall portion 35. In other words, the guide tube 40 extends along the central axis A. A gap is formed between the guide tube 40 and the wall portion 35, and this gap forms the heat gas flow path P. H In addition, inside the guide pipe 40, an exhaust gas flow path P is formed, which is a flow path of the exhaust gas that flows into the outlet unit 30 from the inside of the housing 64. E is formed.

[0039] The guide pipe 40 of this embodiment has an inclined portion 42 and a parallel portion 44. The inclined portion 42 extends so as to approach the central axis A as it approaches the downstream side. The parallel portion 44 is connected to the downstream end of the inclined portion 42. The parallel portion 44 is a cylindrical portion extending parallel to the central axis A. The upstream end of the inclined portion 42 is fixed to the wall portion 35. This allows the guide pipe 40 to be attached to the wall portion 35. The gap between the upstream end of the inclined portion 42 and the wall portion 35 is blocked around the entire circumference. This allows the exhaust gas that has flowed into the outlet unit 30 from inside the housing 64 to flow from the upstream side into the hot gas flow path P H The inflow of the gas into the tank is suppressed.

[0040] In this embodiment, the inclined portion 42 and the parallel portion 44 are not provided with holes penetrating the inclined portion 42 and the parallel portion 44 in the radial direction dr. As a result, in the section where the guide pipe 40 is arranged, the hot gas does not flow through the exhaust gas flow path P E In addition, in the section where the guide pipe 40 is arranged, the exhaust gas is prevented from flowing into the hot gas flow path P H The inclined portion 42 and / or the parallel portion 44 is prevented from flowing inward. Note that, without being limited thereto, a hole penetrating the inclined portion 42 and / or the parallel portion 44 in the radial direction dr may be provided in the inclined portion 42 and / or the parallel portion 44.

[0041] The downstream edge of the guide pipe 40 (the downstream edge of the parallel portion 44), i.e., the downstream end 46, is located upstream of the downstream edge of the wall portion 35. If the downstream end 46 of the guide pipe 40 is located downstream of the downstream edge of the wall portion 35, when the outlet unit 30 is not connected to the subsequent piping 82, the downstream end 46 may come into contact with other members, causing scratches or deformation of the downstream end 46 and / or the other members. In this embodiment, the downstream end 46 is not located outside beyond the downstream edge of the wall portion 35, so that the downstream end 46 can be prevented from coming into contact with other members.

[0042] The inlet pipe 50 introduces the hot gas generated by the hot gas generator 27 into the hot gas flow path P HSpecifically, the introduction pipe 50 introduces the hot gas into the gap between the wall portion 35 and the guide pipe 40. The wall portion 35 is provided with an opening 52 through which the introduction pipe 50 opens. At the opening 52, the introduction pipe 50 enters the hot gas flow path P. H Opens to.

[0043] The opening 52 is located within a section in which the inclined portion 42 of the guide tube 40 is disposed in the axial direction da. In other words, the opening 52 overlaps with the inclined portion 42 when viewed from the radial direction dr. This allows the hot gas flow path P H The hot gas introduced into the hot gas passage P is guided by the inclined portion 42. H It flows inside toward the downstream side.

[0044] As shown in FIG. 5, the introduction pipe 50 extends in a direction inclined with respect to the radial direction dr at the opening 52. The intersection point between the central axis B of the introduction pipe 50 and the extension surface of the wall portion 35 at the opening 52 is defined as C. The radial direction dr here is defined along a straight line connecting the central axis A and point C in the cross section shown in FIG. 5. The smaller of the two angles formed between the central axis B and the radial direction dr at the opening 52 is defined as angle θ. The angle θ is, for example, 30 degrees or more and 90 degrees or less. The angle θ may be 40 degrees or more and 80 degrees or less. The introduction pipe 50 extends perpendicular to the axial direction da. Not limited to this, the introduction pipe 50 may extend in a direction inclined with respect to the axial direction da at an angle greater than 0 degrees and less than 90 degrees. In particular, the introduction pipe 50 may extend in a direction inclined with respect to the axial direction da so as to move toward the downstream side as it approaches the wall portion 35. In the example shown in FIG. 4 and FIG. 5, the introduction pipe 50 extends in a straight line, but is not limited to this, and the introduction pipe 50 may include a portion that extends in a curved line.

[0045] Next, a method of introducing hot gas into the outlet unit 30 will be described with reference to Fig. 4 to Fig. 6. Fig. 6 is a diagram for explaining a method of introducing hot gas into the outlet unit 30, and in particular is a diagram that diagrammatically illustrates a swirling flow of hot gas generated in the outlet unit 30.

[0046] In this embodiment, the exhaust gas flowing from inside the housing 64 to the downstream pipe 82 flows into the outlet unit 30. The temperature of the exhaust gas is, for example, about 100° C. In the outlet unit 30, an exhaust gas flow path P E The exhaust gas that flows into the outlet unit 30 passes through an exhaust gas flow path P E 4 and 6, the flow of the exhaust gas is indicated by outline arrows labeled with the symbol E. In the section in which the guide pipe 40 is arranged, the exhaust gas does not come into contact with the wall 35 of the outlet unit 30. Note that in the section in which the guide pipe 40 is arranged, the exhaust gas can be heated by heat transferred from the hot gas through the guide pipe 40.

[0047] The hot gas generated in the hot gas generator 27 is introduced into the hot gas flow path P through the inlet pipe 50. H The hot gas is, for example, nitrogen gas heated to 200° C. to 300° C. The hot gas is introduced into the hot gas flow path P through the inlet pipe 50 and the opening 52. H The hot gas introduced into the hot gas passage P is guided by the inclined portion 42 of the guide pipe 40. H 4 to 6, the flow of the hot gas is indicated by an arrow marked with the symbol H.

[0048] As shown in FIG. 5, the inlet pipe 50 extends in a direction inclined with respect to the radial direction dr at the opening 52. This allows the hot gas flow path P H The hot gas introduced into the flow path P is subjected to a force that rotates the gas around the central axis A. H The hot gas introduced into the hot gas flow path P H The hot gas flows downstream inside the outlet unit 30 while rotating around the central axis A. As a result, as shown in Fig. 6, the hot gas introduced into the outlet unit 30 forms a vortex flow that flows in a spiral shape from the upstream side to the downstream side along the inner surface of the outlet unit 30 (wall portion 35).

[0049] As the hot gas forms a swirling flow, centrifugal force acts on the hot gas flow H. Therefore, the hot gas flow H continues to form a swirling flow even after passing the downstream end 46 of the guide pipe 40, and flows into the subsequent pipe 82. At this time, the hot gas flow H advances along the inner surface of the outlet unit 30 (wall portion 35) and the inner surface of the subsequent pipe 82. On the other hand, the exhaust gas flow E after passing the downstream end 46 of the guide pipe 40 advances toward the downstream side inside the swirling flow of the hot gas. Therefore, the exhaust gas flow E advances without contacting the wall portion 35 of the outlet unit 30 and the wall portion of the subsequent pipe 82 within a section having a specific length after passing the downstream end 46 of the guide pipe 40. That is, within this section, the exhaust gas and the hot gas flow substantially without mixing with each other.

[0050] In this section, the exhaust gas is not cooled by the wall 35 of the outlet unit 30 and the wall of the downstream pipe 82. This effectively prevents vaporized components in the exhaust gas from being cooled by the wall 35 of the outlet unit 30 and the wall of the downstream pipe 82, condensing or solidifying (powdering) to become foreign matter and adhering to the wall surface of the pipe 82. This effectively prevents clogging of the pipe 82 due to foreign matter adhering to the wall surface of the pipe 82.

[0051] In this section having a specific length, a swirling flow of hot gas is located outside the exhaust gas flow E. This allows the temperature of the exhaust gas to increase in this section due to the heat of the hot gas. In this case, the vaporized components in the exhaust gas are more effectively prevented from being cooled by the wall 35 of the outlet unit 30 and the wall of the downstream pipe 82 and condensed or solidified.

[0052] When the exhaust gas passes through the section having a specific length, the exhaust gas and the hot gas are mixed together. This causes the temperature of the exhaust gas to rise. Therefore, even after the exhaust gas passes through the section having the specific length, the vaporized components in the exhaust gas are prevented from being cooled and condensed or solidified by the wall 35 of the outlet unit 30 and the wall of the subsequent piping 82.

[0053] The specific length of the section where the exhaust gas and the hot gas do not substantially mix can vary depending on the flow rate and velocity of the exhaust gas, the flow rate and velocity of the hot gas, the arrangement angle of the introduction pipe, and the like.

[0054] The filter device 60 of this embodiment is a filter device 60 for removing foreign matter contained in exhaust gas, and comprises a housing 64, a filter unit 72 housed in the housing 64, and an outlet unit 30 that connects the housing 64 to a subsequent piping 82 and causes the exhaust gas that has passed through the filter unit 72 to flow into the piping 82, and the outlet unit 30 forms a vortex flow that flows spirally from the upstream side to the downstream side of the exhaust gas flow along the inner surface of the outlet unit 30 by means of hot gas introduced inside the outlet unit 30.

[0055] According to such a filter device 60, the hot gas forms a swirling flow, and centrifugal force acts on the hot gas flow H. Therefore, in a specific section, the hot gas flow H advances along the inner surface of the outlet unit 30 and the inner surface of the subsequent pipe 82. Meanwhile, in the section, the exhaust gas advances without coming into contact with the wall 35 of the outlet unit 30 and the wall of the pipe 82. That is, in this section, the exhaust gas and the hot gas flow without substantially mixing with each other, i.e., separately.

[0056] Therefore, in this section, the exhaust gas is not cooled by the wall 35 of the outlet unit 30 and the wall of the downstream pipe 82. This effectively prevents vaporized components in the exhaust gas from being cooled by the wall 35 of the outlet unit 30 and the wall of the downstream pipe 82, condensing or solidifying (powdering) to become foreign matter and adhering to the wall surface of the pipe 82. Therefore, clogging of the pipe 82 due to foreign matter adhering to the wall surface of the pipe 82 can be prevented.

[0057] In the filter device 60 of this embodiment, the outlet unit 30 has a wall portion 35 and a guide tube 40 arranged inside the wall portion 35, and a hot gas flow path P through which the hot gas passes is formed between the wall portion 35 and the guide tube 40. H is formed.

[0058] According to such an outlet unit 30, the exhaust gas flow E and the hot gas flow H can be caused to flow toward the downstream side while remaining separated from each other within the section in which the guide pipe 40 is arranged. As a result, the exhaust gas flow E and the hot gas flow H flow without substantially mixing with each other even on the downstream side of the guide pipe 40. Therefore, it is possible to further suppress the vaporized components in the exhaust gas from being cooled and condensed or solidified on the wall 35 of the outlet unit 30 and the wall of the downstream pipe 82.

[0059] Furthermore, in the section in which the guide pipe 40 is disposed, the exhaust gas can be heated by heat transferred from the hot gas through the guide pipe 40. This also makes it possible to further suppress the vaporized components in the exhaust gas from being cooled and condensed or solidified on the wall 35 of the outlet unit 30 and the wall of the downstream pipe 82.

[0060] In the filter device 60 of this embodiment, the guide tube 40 has an inclined portion 42 extending toward the central axis A as it approaches the downstream side, and a parallel portion 44 connected to the downstream end of the inclined portion 42 and extending parallel to the central axis A.

[0061] According to such a filter device 60, the inclined portion 42 can appropriately guide the exhaust gas flow E and the hot gas flow H. In addition, the parallel portion 44 can allow the exhaust gas flow E and the hot gas flow H to flow downstream while being separated from each other.

[0062] In the filter device 60 of this embodiment, the outlet unit 30 has a hot gas flow path P H and an opening 52 at the wall portion 35 through which the introduction pipe 50 opens.

[0063] In the filter device 60 of this embodiment, the introduction pipe 50 extends in a direction inclined with respect to the radial direction dr at the opening 52 .

[0064] According to such a filter device 60, a swirling flow of hot gas can be formed in the outlet unit 30 by using the inflow pressure of the hot gas from the inlet pipe 50 as a driving force. Therefore, a swirling flow of hot gas can be formed with a simple configuration.

[0065] Modifications of this embodiment will be described with reference to Figures 7 to 11. In the following description and the drawings used in the following description, parts that can be configured similarly to the above-described embodiment will be designated by the same reference numerals as those used for the corresponding parts in the above-described embodiment, and duplicated descriptions will be omitted.

[0066] 7 is a vertical cross-sectional view showing a modified example of the filter device 60. In this modified example, the filter unit 72 is disposed in contact with the lid portion 68 of the housing 64. In addition, a gap is formed between the lower end of the filter unit 72 and the bottom of the main body portion 66 of the housing 64.

[0067] In this modified example, the first pipe 81 is connected to the bottom of the main body 66. A lower cover plate 91 is attached to the lower end of the filter unit 72. The lower cover plate 91 is a member for preventing exhaust gas that has flowed in from the first pipe 81 and has not passed through the filter unit 72 from heading toward the second pipe 82. The filter unit 72 is formed with a through hole that passes through the filter unit 72 in the axial direction. The lower cover plate 91 is disposed so as to close at least the lower end of this through hole.

[0068] In this modification, the exhaust gas that has flowed into the housing 64 from the first piping 81 hits the lower cover plate 91 and flows toward the side wall of the housing 64. Thereafter, the exhaust gas passes through the filter unit 72 from the outside toward the inside in the radial direction of the filter unit 72, thereby removing at least a portion of the particulate matter contained in the exhaust gas.

[0069] 8 is a vertical cross-sectional view showing another modified example of the filter device 60. In this modified example, the filter unit 72 is disposed away from the lid portion 68 of the housing 64 and away from the bottom of the housing 64. That is, a gap is formed between the upper end of the filter unit 72 and the lid portion 68, and a gap is formed between the lower end of the filter unit 72 and the bottom of the housing 64.

[0070] An upper cover plate 92 is attached to the upper end of the filter unit 72. The upper cover plate 92 is a member for preventing exhaust gas that has flowed in from the first piping 81 and has not passed through the filter unit 72 from heading toward the second piping 82. A guide pipe 93 is connected to the center of the upper cover plate 92. The guide pipe 93 communicates with a through hole formed in the center of the upper cover plate 92. The guide pipe 93 has a function of guiding the exhaust gas that has passed through the filter unit 72 toward the outlet unit 30. The guide pipe 93 may also have a function of holding the filter unit 72 by suspending it from the lid portion 68.

[0071] In this modification, the first pipe 81 is connected to the lid 68 of the housing 64. The exhaust gas that flows into the housing 64 from the first pipe 81 passes through the filter unit 72 from the outside to the inside in the radial direction of the filter unit 72. This removes at least a part of the fine particles contained in the exhaust gas. The exhaust gas then passes through the through-hole of the upper cover plate 92 and the guide pipe 93 toward the outlet unit 30.

[0072] The lid portion 68 adjacent to the outlet unit 30 into which the hot gas is introduced can become relatively hot due to the transfer of heat from the hot gas. In this case, the portion of the filter unit 72 adjacent to the lid portion 68 may become hot and be damaged. In this modification, the filter unit 72 is disposed away from the lid portion 68, so that it is possible to prevent the filter unit 72 from becoming hot due to the heat transferred from the hot gas. Therefore, it is possible to prevent damage to the filter unit 72 due to heat.

[0073] Fig. 9 is a longitudinal sectional view showing yet another modified example of the filter device 60. Fig. 10 is a transverse sectional view of the filter device 60 corresponding to the line XX in Fig. 9. The filter device 60 of this modified example has a spiral flow path 95 having a spiral shape when viewed along the central axis (see Fig. 10). The filter device 60 has a partition wall 96 arranged in the housing so as to form a continuous spiral flow path 95, and a filter member 97 arranged on at least one surface of the partition wall 96.

[0074] The filter member 97 is provided along the inner surface of the partition wall 96. The filter member 97 is located radially outward in the spiral flow passage 95. As the exhaust gas comes into contact with the filter member 97 and travels along, impurities such as reaction products and other fine particles including mist and dust are captured by the filter member 97. Such a filter member 97 is made of, for example, a fiber material. The filter member 97 is preferably made of a fiber material having excellent heat resistance and chemical resistance. The fiber material constituting the filter member 97 is not particularly limited as long as it satisfies the above requirements, but is preferably a nonwoven fabric from the viewpoint of ease of manufacture and the like.

[0075] The exhaust gas flowing in from the first pipe flows inside the spiral passage 95 while rotating around the central axis. At this time, centrifugal force acting toward the outside of the spiral passage 95 acts on fine particles contained in the exhaust gas. As a result, the fine particles contained in the exhaust gas come into contact with the filter member 97 and are captured by the filter member 97. A filter device 60 having such a spiral passage 95 can be configured in the same manner as the filter devices described in, for example, Japanese Patent No. 4636640 and Japanese Patent No. 4864283.

[0076] Fig. 11 is a vertical cross-sectional view showing yet another modified example of the filter device 60. The filter device 60 shown in Fig. 9 includes a spiral passage 95 and a filter unit 72. The filter unit 72 is disposed downstream of the spiral passage 95 along the flow of the exhaust gas flow E. In the example shown in Fig. 11, the filter unit 72 is disposed above the spiral passage 95. Note that, in the example shown in Fig. 11, the filter unit 72 is disposed in contact with the lid portion 68, but as in the example shown in Fig. 8, the filter unit 72 may be disposed apart from the lid portion 68. [Explanation of symbols]

[0077] 5 Manufacturing equipment 10. Abatement Systems 12 Vacuum Pump 14 Abatement equipment 20 Piping 21 Piping 22 Piping 23 Piping 24 Piping 27 Hot Gas Generator 28 First hot gas generator 29 Second hot gas generator 30 Exit Unit 31 First Exit Unit 32 2nd Exit Unit 33 First Opening 34 Second Opening 35 Wall 40 Guide tube 42 Slope 44 Parallel section 46 Downstream end 50 Introductory pipe 52 Opening 60 Filter Device 61 First filter device 62 Second Filter Device 64 Case 66 Main body 68 Lid 72 Filter Unit 74 Partition Wall 76 Collision plate 81 First Pipe 82 Second Pipe 91 Lower cover plate 92 Upper cover plate 93 Guidance tube 95 Spiral Channel 96 Bulkhead 97 Filter Materials E Exhaust gas flow H Hot gas flow P E Exhaust gas flow path P H Hot Gas Path A Center axis da Axial direction dr radial direction dc circumferential direction

Claims

1. A filter device for removing foreign matter contained in exhaust gas, A housing and A filter unit housed in the housing; and an outlet unit that connects the housing to a downstream pipe and causes the exhaust gas that has passed through the filter unit to flow into the pipe; A filter device in which the outlet unit forms a vortex flow that flows spirally from the upstream side to the downstream side of the exhaust gas flow along the inner surface of the outlet unit by hot gas introduced into the outlet unit.

2. The outlet unit has a wall and a guide tube disposed inside the wall, The filter device according to claim 1 , wherein a hot gas flow passage through which the hot gas passes is formed between the wall portion and the guide tube.

3. 3. The filter device according to claim 2, wherein the guide tube has an inclined portion extending toward the central axis as it approaches the downstream side, and a parallel portion connected to the downstream end of the inclined portion and extending parallel to the central axis.

4. 4. The filter device according to claim 2, wherein the outlet unit has an inlet pipe for introducing the hot gas into the hot gas flow path, and an opening in the wall through which the inlet pipe opens.

5. The filter device according to claim 4 , wherein the inlet pipe extends in a direction inclined relative to a radial direction at the opening.

Images