JP2009112905A - Exhaust treatment device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an exhaust treatment device capable of efficiently removing harmful gas components without increasing its shaft power. <P>SOLUTION: Atomizing sections 24 for atomizing liquid droplets formed on the front face 20b of a main disc 20 are disposed on the radial outer end 20c of the main disc 20 disposed in a casing 11, whereby the diameter of the liquid droplets is made smaller to bring a larger amount of harmful gas components into contact with a cleaning liquid. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an exhaust gas treatment apparatus that removes harmful components from exhaust gas generated in various manufacturing processes.

  In each process at the time of semiconductor manufacturing, exhaust gas containing dust such as silicon dioxide is discharged in addition to acid gas and alkaline gas, but since these exhaust gases are toxic, they are detoxified before being released to the atmosphere. There is a need. Examples of the detoxifying device include wet cleaning towers such as a perforated plate tower and a spray tower that are less likely to clog dust. However, when exhaust gas is treated using such a wet cleaning tower, dust adheres to the impeller and the tower body, so that there is a problem that regular cleaning is required and maintenance costs increase.

  As an exhaust gas treatment device that solves the problem, an impeller that sends exhaust gas radially outward, a casing in which the impeller is provided, a drive unit that rotates the impeller, and a path through which the exhaust gas is guided to the casing And an injection nozzle that sprays the cleaning liquid toward the impeller (see, for example, Patent Document 1).

In this exhaust gas treatment apparatus, the cleaning liquid sprayed toward the impeller becomes droplets on the impeller, and the dust and toxic gas components contained in the exhaust gas are removed by contact between the droplets and the exhaust gas. It has become so.
JP 62-210029 A

  In the exhaust gas treatment apparatus of Patent Document 1, the sprayed mist-like cleaning liquid adheres onto the impeller and further travels to the radially outer end by centrifugal force to become droplets. The dust in the exhaust gas can be captured after the droplet leaves the impeller and hits the casing. However, regarding the toxic gas component in the exhaust gas, since the gas component is distributed almost entirely in the casing, the cleaning liquid is biased on the impeller. However, it can only be brought into contact with the cleaning liquid, and there is a problem that the gas component cannot be efficiently removed only by the exhaust gas treatment device.

  Therefore, in order to bring a lot of the gas components into contact with the cleaning liquid, it is conceivable to increase the rotational speed of the impeller and reduce the droplet diameter on the impeller. However, if it does in this way, the shaft power for rotating an impeller will become excessive with respect to the required static pressure.

  An object of the present invention is to provide an exhaust gas treatment apparatus capable of efficiently removing toxic gas components without increasing shaft power in view of the above-described problems of the prior art.

  In order to achieve the above object, the present invention takes the following technical means.

  That is, the exhaust gas treatment apparatus of the present invention includes an impeller for sending exhaust gas radially outward, a casing having the impeller provided therein and having an exhaust gas suction port and a discharge port, and a drive for rotating the impeller. And an injection nozzle that is disposed in a path through which exhaust gas is guided to the casing and sprays cleaning liquid toward the impeller to generate liquid droplets on the impeller. It is characterized in that a refining section for refining the droplets generated on the impeller is provided at the radially outer end of the impeller.

  According to the exhaust gas treatment apparatus of the present invention, since the droplet generated in the impeller is made fine by the miniaturization unit, the droplet diameter can be reduced without increasing the rotational speed of the impeller. As a result, many toxic gas components are brought into contact with the cleaning liquid, and the gas components can be efficiently removed without increasing the shaft power.

  Moreover, if the said refinement | miniaturization part has many acicular parts which protrude in a radial direction outward from the radial direction outer edge of the said impeller, if the droplet which arose on the impeller by this acicular part is subdivided, Good.

  Moreover, the droplet diameter can be further reduced by arranging the numerous needle-like portions so as to be inclined in the rotation direction of the impeller.

  Moreover, if the said refined | miniaturized part consists of fiber reinforced plastics and the said many acicular parts are comprised with the reinforced fiber contained in the said fiber reinforced plastic, the said refined | miniaturized part can be manufactured easily.

  Further, in the case where the impeller includes a disk-shaped main plate and an annular side plate disposed to face the main plate, the droplet refinement portion is provided at a radially outer end portion of the main plate. It only has to be done.

  Furthermore, it is preferable that an annular dispersion plate is provided between the main plate and the side plate to drop a part of the cleaning liquid sprayed from the spray nozzle.

  In this case, since the sprayed cleaning liquid can be formed into droplets even with the dispersion plate, more cleaning liquid can be formed into droplets. In general, when the exhaust gas treatment device is enlarged, the width between the main plate and the side plate becomes large, and a large amount of exhaust gas passes through the portion. The percentage of toxic gas components that cannot be contacted increases. When the dispersion plate of the present invention is provided, the cleaning liquid can be made into droplets even between the main plate and the side plate, so that the proportion of toxic gas components that cannot contact the droplets can be reduced by the amount provided with the dispersion plate. . Therefore, even when the exhaust gas treatment apparatus is enlarged by providing the dispersion plate, toxic gas components can be efficiently removed.

  Furthermore, it is preferable that the main plate is provided with a diffusion portion that diffuses a part of the cleaning liquid sprayed from the injection nozzle and reaching the main plate into the space in the casing.

  In this case, a part of the cleaning liquid that has reached the main plate is diffused into the space in the casing by the diffusing section, so that more toxic gas components can be brought into contact with the sprayed mist-like cleaning liquid.

  Further, the diffusion part may be configured by a plurality of diffusion blades extending radially about the rotation axis of the main plate.

  As described above, according to the present invention, the droplets of the cleaning liquid are refined by the miniaturization unit, and many toxic gas components are brought into contact with the cleaning liquid, so that the gas components are efficiently removed without increasing the shaft power. can do.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a process flow diagram showing a main part of an exhaust gas treatment system 2 in which an exhaust gas treatment apparatus 1 according to one embodiment (first embodiment) of the present invention is used. The treatment system 2 includes an exhaust gas treatment device 1 that removes toxic gas components (hereinafter simply referred to as gas components) and dust contained in the pretreated exhaust gas 3, and a treatment gas discharged from the exhaust gas treatment device 1. 4 is sent to the mist catcher tower 5, a circulation tank 6 for storing the water separated by the mist catcher tower 5, and a circulation pump 7 for sending the water stored in the circulation tank 6 to the exhaust gas treatment device 1. And are installed.

  The exhaust gas 3 sent to the exhaust gas treatment device 1 becomes a treatment gas 4 containing a large amount of moisture in the exhaust gas treatment device 1, and the moisture in the treatment gas 4 is changed by passing the treatment gas 4 through the mist catcher tower 5. It is separated together with the gas component and dust and becomes purified gas 8 which is released to the atmosphere. The water separated in the mist catcher tower 5 is stored in the circulation tank 6, and the water stored in the circulation tank 6 is sent again to the exhaust gas treatment device 1 by the circulation pump 7. The circulation tank 6 is provided with a water supply unit 30 for replenishing fresh water, a drainage unit 31 for draining overflowed water, an overflow sensor 32, and the like. Is provided.

  FIG. 2A is a front view of the exhaust gas treatment apparatus 1, and FIG. 2B is a side view in which a part of the exhaust gas treatment apparatus 1 is cut away. The exhaust gas treatment device 1 includes an impeller 10 that sends the exhaust gas 3 radially outward, a casing 11 in which the impeller 10 is provided, a drive motor 12 (drive unit) that rotates the impeller 10, And an injection nozzle 13 for spraying the cleaning liquid. In the following description, the left side in FIG. 2 (b) is referred to as the front side, and the right side in FIG. 2 (b) is referred to as the rear side.

  The casing 11 includes a front container 14 and a rear container 15. A through hole 15a is formed in the center of the rear container 15, and a drive shaft 16 connected to the drive motor 12 disposed on the rear side of the casing 11 is passed through the through hole 15a. Both the front container 14 and the rear container 15 are formed in a container shape, and an opening part 14a serving as an exhaust gas passage is formed in the front part of the front container 14 among them. A cylindrical enlarged diameter portion 17 extending from the inside of the casing 11 to the outside is fixed to the opening portion 14a.

  The diameter-expanded portion 17 is increased in diameter from the inside of the casing 11 toward the outside, and constitutes a suction port 18 through which the introduced exhaust gas 3 is sucked into the impeller 10 in the casing 11. Further, a discharge port 19 configured by combining a part of the front container 14 and a part of the rear container 15 is provided in the side wall of the casing 11, and the exhaust gas 3 sucked into the casing 11 is The processing gas 4 is discharged from the discharge port 19.

  A cylindrical introduction pipe 33 extending in the front-rear direction is attached to the front end of the enlarged diameter portion 17. A nozzle pipe introduction part 34 is provided on the side surface of the introduction pipe 33, and the nozzle pipe 35 through which the cleaning liquid is passed is introduced to the middle part in the front-rear direction of the introduction pipe 33 via the nozzle pipe introduction part 34. . An injection nozzle 13 directed toward the casing 11 is provided at the tip of the nozzle tube 35, and the cleaning liquid 27 that has passed through the nozzle tube 35 is sprayed from the injection nozzle 13 toward the impeller 10 in the casing 11. It has come to be.

  3 is a front view in which a part of the impeller 10 is cut away, and FIG. 4 is a cross-sectional view taken along line AA in FIG. The impeller 10 includes a disk-shaped main plate 20, an annular side plate 21 disposed opposite to the front side of the main plate 20, a blade plate 22 extending in the front-rear direction provided between the main plate 20 and the side plate 21, Furthermore, the diffusion part 23 provided in the rotation center part of the main board 20 and the refinement | miniaturization part 24 provided in the radial direction outer end part 20c of the main board 20 are provided.

  The main plate 20 has a diameter such that a required gap with the casing 11 is formed (see FIG. 2B), and the drive shaft 16 is fixed to the center of the rear surface. As shown in FIG. 4, the side plate 21 is formed so as to reduce in diameter toward the front side. Thereby, the exhaust gas 3 sent to the enlarged diameter portion 17 is sucked into the space 28 in the impeller 10.

  As shown in FIGS. 3 and 4, the blade plate 22 is curved in a convex shape in the circumferential direction, and its front end is fixed to the rear surface of the side plate 21 and its rear end is fixed to the front surface 20 b of the main plate 20. Has been. Eight blade plates 22 are provided so as to connect the main plate 20 and the side plate 21, and protrude slightly inward from the radial inner end of the side plate 21 from the radial outer end position of the main plate 20. It extends radially to the position. Accordingly, the exhaust gas 3 that has been sucked into the impeller 10 passes between the adjacent blade plates 22, 22 and travels radially outward of the impeller 10.

  The diffusing portion 23 is composed of eight diffusing blades 25 that extend radially at equal angles around the center of rotation of the main plate 20. As shown in FIG. 4, each diffusion blade 25 is formed in a plate shape having a length in the front-rear direction shorter than the radially outer end edge of the blade plate 22 and is erected on the front surface of the main plate 20. The main plate 20, the diffusion blade 25, the blade plate 22, and the side plate 21 configured in this way are rotated together by the drive shaft 16 fixed to the main plate 20.

  Note that the main plate 20, the diffusion blade 25, the blade plate 22, and the side plate 21 are all made of glass fiber reinforced plastic (GFRP), and high corrosion resistance is ensured. Moreover, the glass fiber contained in this material is subjected to a water repellent treatment, and the cleaning liquid tends to be droplets on the surface of each member. In addition, the constituent material of each member is not limited to the above materials, and FRP reinforced with carbon fibers or other reinforcing fibers, or other materials, as long as the required strength and corrosion resistance can be ensured. Can also be configured. In this embodiment, the diameter of the main plate 20 is about 400 mm, the radial dimension of the diffusion blade 25 is about 100 mm, and the longitudinal dimension (height) is about 60 mm. In addition, the dimension of each said member is not limited to these, It can change suitably.

  As shown in FIG. 3, the miniaturization portion 24 is provided over the entire circumference of the radially outer end portion 20 c of the main plate 20. As shown in the enlarged view of FIG. 3, the miniaturization part 24 has a large number of needle-like parts 26. These many needle-like parts 26 protrude radially outward from the radial outer edge 20a of the main plate 20 and have a brush shape along the radial outer edge 20a of the main plate 20.

  Further, the numerous needle-like portions 26 are inclined toward the rotation direction of the impeller 10 (clockwise direction in FIG. 3). The miniaturization part 24 is comprised by FRP, and many needle-like parts 26 are comprised by exposing the oriented reinforcement fiber contained in FRP. In the present embodiment, the protruding length of the needle-like portion 26 from the radial outer edge 20a of the main plate 20 is about 5 mm. Note that the protruding length of the needle-like portion 26 can be changed as appropriate.

  The miniaturized portion 24 is configured as an overlay layer in which a plurality of strip-shaped GFRPs are attached along the circumferential direction of the main plate 20. Hereinafter, the manufacturing method of this refinement | miniaturization part 24 is demonstrated in detail. A strip-shaped glass fiber woven fabric having a required length (corresponding to the length in the circumferential direction) and a required width (corresponding to the length in the radial direction) is prepared. The edge portion on one side in the longitudinal direction of each glass fiber woven fabric is processed so that a large number of oriented glass fibers of 5 mm or more protrude obliquely from the edge portion. Specifically, the glass fiber woven in the longitudinal direction at the cut edge in the longitudinal direction of the cut glass fiber woven fabric may be removed, and the fiber in the short-side direction may be long projected.

  Each glass fiber woven fabric is impregnated with room temperature-curable liquid polyester to form an impregnated woven fabric. At this time, the polyester is prevented from adhering to a portion where a large number of glass fibers are projected. Each impregnated woven fabric is arranged along the outer end portion 20c such that a large number of the protruded glass fibers protrude radially outward from the outer end edge 20a of the main plate 20. Then, each of the impregnated woven fabrics is pressed from above with a roller, and the respective impregnated woven fabrics are pressure-bonded to the main plate 20. Thereafter, in order to remove bubbles contained in the polyester, defoaming treatment is performed, and curing is performed at room temperature, whereby the refined portion 24 is obtained. In addition, as long as it has corrosion resistance as a material which comprises the refinement | miniaturization part 24, you may use other resin, such as other fiber materials, such as carbon fiber, and epoxy resins other than polyester, for example.

  Next, the point that the gas component and dust contained in the exhaust gas 3 are removed by the exhaust gas treatment device 1 will be described. The exhaust gas 3 that has entered the introduction pipe 33 is sucked into the space 28 in the impeller 10 from the suction port 18. At the same time, the mist-like cleaning liquid 27 in the form of a mist from the spray nozzle 13 provided in the introduction pipe 33 is continuously sprayed into the impeller 10. A part of the mist-like cleaning liquid that has reached the main plate 20 is diffused into the space 28 in the impeller 10 by the diffusion blade 25 and comes into contact with the gas component and dust to capture the gas component and dust.

  The mist-like cleaning liquid that has reached the main plate 20 and has not been diffused by the diffusion blades 25 travels radially outward from the front surface 20b of the main plate 20 by the centrifugal force into droplets. The droplet cleaning liquid that has been made into droplets reaches the miniaturization portion 24 of the main plate 20 and is refined by a large number of needle upper portions 26 to become a fine cleaning liquid. At this time, since a large number of needle upper portions 26 are inclined toward the rotation direction, the droplet cleaning liquid is refined into smaller droplets. The fine cleaning liquid leaves the main plate 20 and collides with the inner surface of the casing 11. As a result, gas components and dust near the main plate 20 are captured by the droplet cleaning liquid present on the front surface 20 b of the main plate 20, the micronized cleaning liquid present in the micronization unit 24, and the micronized cleaning liquid separated from the main plate 20. . In the space 28 between the main plate 20 and the side plate 21, gas components and dust are captured by the mist cleaning liquid diffused by the diffusion blade 25 and the mist cleaning liquid sprayed from the injection nozzle 13.

  As described above, since the main plate 20 of the exhaust gas treatment apparatus 1 according to the present embodiment is provided with the refinement unit 24, the droplet cleaning liquid generated on the front surface 20b of the main plate 20 is refined, and the droplet diameter is reduced. Can be reduced. Further, since the main plate 20 is provided with a plurality of diffusion blades 25 for diffusing the mist-like cleaning liquid sprayed from the injection nozzle 13, the mist-like cleaning solution that has reached the main plate 20 is not made into droplets by the main plate 20. It can be diffused and remain with a small droplet size.

  According to the exhaust gas treatment apparatus 1 of the present embodiment, the cleaning liquid having a small droplet diameter is disposed in the space in the casing 11 including the front surface 20b of the main plate 20, the vicinity of the main plate 20, and the space 28 between the main plate 20 and the side plate 21. Therefore, not only dust but also many gas components can be captured by being brought into contact with the cleaning liquid. Therefore, even if the shaft power is not increased to increase the rotational speed of the impeller 10, a large amount of gas components can be efficiently removed by contacting with the cleaning liquid.

  Further, since the cleaning liquid always comes into contact with the impeller 10, it is difficult for dust to adhere to the impeller 10 and maintenance is easy. Further, since the impeller 10 is constantly washed with the cleaning liquid, the initial blowing ability can be maintained for a long time, and the rotation is unbalanced due to the adhesion of dust to the impeller 10. Can be prevented. In this way, if the exhaust gas treatment apparatus 1 is used, maintenance management of the treatment system 2 becomes very easy. Further, the apparatus is more compact than a wet cleaning tower such as a perforated plate tower or a spray tower, and it can be installed in a small installation space, which is economical.

  5 and 6 show a second embodiment of the exhaust gas treatment apparatus according to the present invention. The difference between the exhaust gas treatment apparatus 40 of the present embodiment and the exhaust gas treatment apparatus 1 of the first embodiment is that the diffusion blade 25 is not provided, and an annular dispersion plate 41 is provided between the main plate 20 and the side plate 21. This is the point. In addition, the point which is common in 1st Embodiment attaches | subjects the same code | symbol, and abbreviate | omits the description.

  The dispersion plate 41 is disposed opposite to the main plate 20 at a substantially central portion between the rear end of the side plate 21 and the main plate 20, and the inner diameter size and the outer diameter size thereof are substantially the same as the inner diameter size and the outer diameter size of the side plate 21. It is the same. Further, a finer portion 42 similar to that of the first embodiment is provided at the radially outer end 41a of the dispersion plate 41. Further, the finer portion 24 is also provided at the radially outer end 20c of the main plate 20 as in the first embodiment. Due to the presence of the dispersion plate 41, the mist-like cleaning liquid sprayed from the spray nozzle 13 can be made into droplets by the dispersion plate 41 and the main plate 20. The droplet cleaning liquid transmitted to the radially outer end 41a of the dispersion plate 41 can be refined by the refinement unit 42 provided on the dispersion plate 41.

  According to the exhaust gas treatment apparatus 40 of the present embodiment, not only the main plate 20 but also the dispersion plate 41 generates droplet cleaning liquid, and the droplet cleaning liquid is refined by the miniaturization unit 42, so that a large amount of gas components and dust are removed. It can be efficiently removed by contacting with the cleaning liquid. Further, in the case of the exhaust gas treatment apparatus not provided with the dispersion plate 41 shown in the present embodiment, when the size is increased, the width between the main plate and the side plate becomes large, and a large amount of exhaust gas passes through the portion. Compared to the device, there are more toxic gas components that cannot contact the droplets on the main plate. If the dispersion plate 41 is provided as in the present invention, the cleaning liquid can be made into liquid droplets even between the main plate 20 and the side plate 21, so that toxic gas components that cannot come into contact with the liquid droplets are reduced. Therefore, even when the exhaust gas treatment device 40 is enlarged, the toxic gas component can be efficiently removed by providing the dispersion plate 41.

  In addition, the said embodiment is an illustration and is not limited. For example, the orientation direction and length of the acicular portion of the miniaturized portion, and the location where the miniaturized portion is provided may be changed. What is necessary is just to change suitably the shape, dimension, etc. of a casing, a main board, a side board, and a wing board. Moreover, the exhaust gas treatment apparatus can be applied to various exhaust gas treatment systems, and facilities provided before and after the exhaust gas treatment apparatus are not limited.

  The present invention can be applied to, for example, an exhaust gas treatment apparatus for removing harmful components from exhaust gas generated in a semiconductor manufacturing apparatus.

It is a processing flow figure showing the important section of the exhaust gas processing system in which the exhaust gas processing apparatus concerning a 1st embodiment of the present invention was used. (A) is a front view of an exhaust gas treatment apparatus, (b) is a side view in which a part of the exhaust gas treatment apparatus is cut away. It is the front view which notched a part of impeller. FIG. 4 is a sectional view taken along line AA in FIG. 3. It is the front view which notched a part of impeller of the exhaust gas processing apparatus which concerns on 2nd Embodiment of this invention. FIG. 6 is a sectional view taken along line B-B in FIG. 5.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,40 Exhaust gas processing apparatus 2 Processing system 5 Mist catcher tower 10 Impeller 11 Casing 13 Injection nozzle 18 Suction port 19 Discharge port 20 Main plate 21 Side plate 22 Blade plate 24, 42 Refinement part 23 Diffusion part 25 Diffusion blade 26 Needle-like part 27 Cleaning liquid 41 Dispersion plate

Claims (8)

An impeller for sending exhaust gas radially outward;
A casing having the impeller provided therein and having a suction port and a discharge port for exhaust gas;
A drive unit for rotating the impeller;
An injection nozzle that is disposed in a path through which exhaust gas is guided to the casing and sprays cleaning liquid toward the impeller to generate liquid droplets on the impeller;
An exhaust gas treatment apparatus comprising: a refinement unit that is provided at a radially outer end of the impeller and refines the droplets generated on the impeller.   The exhaust gas treatment apparatus according to claim 1, wherein the miniaturization part has a large number of needle-like parts protruding radially outward from a radial outer edge of the impeller.   The exhaust gas treatment apparatus according to claim 2, wherein the plurality of needle-like portions are arranged so as to incline toward a rotation direction of the impeller.   The exhaust gas treatment apparatus according to claim 2 or 3, wherein the miniaturized part is made of fiber reinforced plastic, and the plurality of needle-like parts are constituted by reinforced fibers contained in the fiber reinforced plastic.   The impeller includes a disk-shaped main plate and an annular side plate disposed to face the main plate, and the finer portion is provided at a radially outer end of the main plate. The exhaust gas treatment apparatus according to any one of 4.   The exhaust gas treatment apparatus according to claim 5, wherein an annular dispersion plate is provided between the main plate and the side plate to make a part of the cleaning liquid sprayed from the spray nozzle into droplets.   The exhaust gas treatment apparatus according to claim 5 or 6, wherein the main plate is provided with a diffusion unit that diffuses a part of the cleaning liquid sprayed from the injection nozzle and reaching the main plate into the space in the casing.   The exhaust gas processing apparatus according to claim 7, wherein the diffusion unit is configured by a plurality of diffusion blades extending radially about a rotation axis of the main plate.

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