JP4642559B2 - Impurity removal device - Google Patents

Description

  The present invention relates to an impurity removal apparatus that absorbs and removes soluble gas in processing air by gas-liquid contact.

Conventionally, the following methods for removing soluble gas by gas-liquid contact have been proposed.
(1) A method of absorbing and removing gas in spray water by performing gas-liquid contact with spray water droplets by spraying water directly onto the treated air (see Patent Document 1). In this method, the spray water is captured and recovered by an eliminator installed downstream in the processing wind tunnel.
(2) A method in which an air-permeable filler is added to the method (1) for the purpose of increasing the gas-liquid contact area (see Patent Document 2). This is a means capable of making the apparatus compact because the gas-liquid contact area can be surely increased as compared with the method (1). However, even in this method, there is a drop of water droplets from the filler, so it is essential to install an eliminator downstream.
(3) A method for further reducing the pressure loss by using a metallic honeycomb as a filler as a method for further compacting the method (2) (see Patent Document 3). In this method, by directly distributing water from the upper part of the filler, the water spray portion is eliminated, and the apparatus can be made more compact. However, because there is a drop of water droplets from the filler, it is essential to install an eliminator downstream.
(4) As a method for further reducing the method of (3) above, there is a method in which the eliminator itself has a function of gas-liquid contact without using the filler used for the purpose of gas-liquid contact (Patent Literature). 4). By adopting an eliminator made of a hydrophilic material, a water film is formed on the surface of the eliminator to absorb and remove gas. Furthermore, since the structure itself has an eliminator function, splash water can be prevented. It is.

JP 2002-035524 A JP 2002-005474 A JP 2003-222363 A JP 09-239224 A

By the way, in the removal of the soluble gas present in the air by the gas-liquid contact method, the following requirements must be satisfied.
First, as an absolutely necessary function, the gas absorption rate can be increased by increasing the gas-liquid contact area x contact time. It is possible to prevent water droplets from scattering to the downstream side of the treatment area. As a desirable function and performance, air pressure loss is low. And it is mentioned that there is as little water supply amount (circulation water amount) as possible.

Considering the above-described conventional technology in view of the above conditions, first, in the technology disclosed in Japanese Patent Application Laid-Open No. 2002-035524, in order to increase the gas-liquid contact area × treatment time, the apparatus is large and the amount of circulating water is large. As the requirements for installation space, equipment cost reduction, operation cost and energy reduction become stronger, it is difficult to adopt such technology.
Further, in the techniques disclosed in Japanese Patent Application Laid-Open Nos. 2002-005474 and 2003-222363, the amount of circulating water can be reduced by using a filler, but it is necessary to separately install an eliminator for preventing water droplet scattering on the downstream side. There is a limit to downsizing.
In Japanese Patent Application Laid-Open No. 09-239224, since the eliminator has all the gas-liquid contact function, there is a limit in reducing pressure loss. This is because the eliminator, in principle, captures scattered water droplets by inertial collision, and therefore has a higher ventilation resistance than a simple filler.

  The present invention has been made in view of the above points, and an object of the present invention is to make the apparatus more compact and reduce pressure loss than before in a device for removing soluble gas from processing air by gas-liquid contact. .

In order to achieve the above object, the impurity removing device of the present invention is a device that absorbs and removes the soluble gas in the processing air by gas-liquid contact, and allows the processing air to flow from upstream to downstream inside thereof. A processing chamber having a gas-liquid contact material made of a hydrophilic material on the upstream side and a hydrophilic eliminator on the downstream side, and water supply for supplying water to the gas-liquid contact material A plurality of corrugated plates made of a hydrophilic material only, the gas-liquid contact material, and arranged in parallel in the width direction in the chamber in a vertically standing state. The first corrugated portion and the groove portion of the corrugated plate are directed obliquely downward toward the downstream side, and the second corrugated plate portion and the groove portion of the corrugated sheet are directed obliquely downward toward the upstream side. DOO is a structure that are alternately arranged, the gas-liquid contact Some of the water supplied toward the is supplied directly to the hydrophilic eliminator from the gas-liquid contact member is configured to wet the surface of the hydrophilic eliminator.

As described above, in the present invention, the gas-liquid contact material made of a hydrophilic material is first provided on the upstream side, and the hydrophilic eliminator is disposed on the downstream side. The eliminator having a large pressure loss can have a minimum configuration that can satisfy the water droplet capturing performance. Therefore, the pressure loss can be reduced accordingly. The gas-liquid contact material can also be reduced by the hydrophilic eliminator because it has a gas removal function. As a result, the entire processing unit can be made more compact than before, and low pressure loss can be achieved. And part of the supplied toward the gas-liquid contact member water is fed directly to the hydrophilic eliminator from the gas-liquid contact member, it is arranged that wets the surface of the hydrophilic eliminator, gas-liquid contact member It is not necessary to supply water independently to both the hydrophilic eliminator and the size of the entire apparatus can be made compact from this point of view.

Then the gas-liquid contact member only, a plurality of corrugated plates made of a hydrophilic material is arranged in parallel in the width direction of the chamber in a state of being erected vertically, and ridges in the corrugated plate and the groove The first corrugated plate that is directed obliquely downward toward the downstream side and the second corrugated plate in which the ridges and grooves in the corrugated plate are directed obliquely downward toward the upstream side are alternately arranged. Therefore, of the water supplied to the gas-liquid contact material, the water for the first corrugated plate is supplied to the downstream hydrophilic eliminator, and the water for the second corrugated plate is the gas-liquid contact material. It is used for water distribution to the whole. In other words, if only the first corrugated plate is formed with the ridges and grooves directed obliquely downward toward the downstream side, a large amount of water flows to the downstream end side, and the entire corrugated plate is wet. However, the gas removal performance deteriorates due to the uneven replacement of water. The first corrugated portion and the groove portion in the point wave plate are directed obliquely downward toward the downstream side, and the first corrugated portion and the groove portion in the corrugated sheet are directed obliquely downward toward the upstream side. If the two corrugated plates are arranged alternately, the flow of water collides with each other at the intersection of the ridge and the ridge, so that a lot of water is distributed around the intersection. it can.

  The diagonal angle of the ridge and groove in the first corrugated plate is 10 ° to 80 °, and the diagonal angle of the ridge and groove in the second corrugated plate is 10 ° to 80 °. There should be. The height between the top of the ridge and the bottom of the groove in each corrugated plate (corresponding to the amplitude referred to as “wave”) is 3 to 15 mm, and the top of adjacent ridges. The length between them (corresponding to the period width in terms of “wave”) is preferably 5 to 30 mm.

  The downstream end of the gas-liquid contact material and the upstream end of the hydrophilic eliminator are preferably in contact with each other, but the downstream end of the gas-liquid contact material and the upstream end of the hydrophilic eliminator The distance between them may be 1 to 50 mm.

  The structure of the water supply unit that supplies the gas-liquid contact material may be such that water is supplied directly to the gas-liquid contact material from the upper part of the gas-liquid contact material by a watering device, or upstream of the gas-liquid contact material such as a spray nozzle. You may spray water on a gas-liquid contact material from the side.

  According to the present invention, an apparatus for removing soluble gas from process air by gas-liquid contact can be made more compact than before, and pressure loss can be reduced.

  Hereinafter, preferred embodiments of the present invention will be described. FIG. 1 shows an outline of the configuration of an impurity removing apparatus 1 according to an embodiment. Inside a substantially rectangular tube-shaped chamber 2, an inlet 3, a HEPA filter, etc. A filter 4, a processing unit 5, a fan 6, and an outlet 7 are provided. The fan 6 is supported by an appropriate panel material 8 for ensuring airtightness.

  The processing unit 5 includes a gas-liquid contact material 11 made of a hydrophilic material and a hydrophilic eliminator 21. In the present embodiment, the downstream end of the gas-liquid contact material 11 and a hydrophilic eliminator are provided. 21 is in contact with the upstream end, and the distance between both ends is zero.

  The gas-liquid contact material 11 is composed of two types of corrugated plates 12 and 13. That is, as shown in FIG. 2, the corrugated sheet 12 as the first corrugated sheet is such that the ridges 12a and the grooves 12b are directed obliquely downward toward the downstream side. The corrugated sheet 13 is such that the protrusion 13a and the groove 13b are directed obliquely downward toward the upstream side. A plurality of these corrugated plates 12 and 13 are arranged in parallel in the width direction in the chamber 2 in a vertically standing state, and the corrugated plates 12 and the corrugated plates 13 are alternately arranged. The length M in the airflow direction of the gas-liquid contact material 11 is set to 150 mm.

  The corrugated plates 12 and 13 are made of a hydrophilic material. For example, a corrugated sheet made of polyester fiber non-woven and press-fitted with silica can be used. Of course, various other hydrophilic materials can be used. The thickness of the corrugated plates 12 and 13 is about 0.5 mm.

  Further, in the present embodiment, as shown in FIG. 3, the depression angle θ1 obliquely below the protrusion 12a and the groove 12b in the corrugated sheet 12 is set to 30 ° C., and the protrusion in the corrugated sheet 13 is provided. The depression angle θ2 obliquely below the portion 13a and the groove 13b is also set to 30 ° C. These depression angles θ1 and θ2 can be arbitrarily set in the range of 10 ° to 80 °.

  Further, as shown in FIG. 4, the height h between the top of the ridge 12a and the bottom of the groove 12b in the corrugated sheet 12 is set to 5 mm, and the length between the tops of adjacent ridges. λ is set to 15 mm. The height h is preferably in the range of 3 to 15 mm, and the length λ is preferably in the range of 5 to 30 mm.

  On the other hand, as shown in FIG. 1 and FIG. 2, the hydrophilic eliminator 21 has a plurality of plates 22 in the chamber 2 so that the plate 22 formed by so-called spelling of the hydrophilic material is set up vertically and parallel to the air flow. Installed and configured. As the hydrophilic material, for example, a non-woven fabric of polyester fiber formed by press molding and silica can be used. Of course, other various hydrophilic materials can be used. The thickness of the plate 22 itself is about 1.0 mm. The length N of the hydrophilic eliminator 21 in the air flow direction is set to 60 mm.

  As shown in FIG. 1, the water supply part 31 which supplies water, for example, pure water, above the gas-liquid contact material 11 uses a sprinkler in this embodiment. As for the water supplied from the water supply part 31, the water supplied to the corrugated sheet 12 descends along the surfaces of the ridges 12a and grooves 12b of the corrugated sheet 12 as shown in FIG. Since the protrusion 12a and the groove 12b have a depression angle on the downstream side, part of the protrusion 12a also flows backward and is supplied to the hydrophilic eliminator 21. On the other hand, about what was supplied to the corrugated sheet 13, as shown in FIG. 6, it goes down along the surface of the protruding part 13a and the groove part 13b of the corrugated sheet 13, but the protruding part 13a and the groove part 13b are Since a depression is added on the upstream side, a part of it flows forward. Since the corrugated plates 12 and 13 are both made of a hydrophilic material, the entire surfaces of the corrugated plates 12 and 13 are covered with a thin water film and are always wet.

  The supplied water is pumped up by a pump 33 from a receiving part 32 installed on the lower surface of the processing part 5 and supplied to a water supply part 31 from a supply pipe 34, and the gas-liquid contact material 11, a hydrophilic eliminator. The water that has fallen along 21 is received by the receiving portion 32. Therefore, the water supplied to the gas-liquid contact material 11 circulates. However, the receiving portion 32 is replenished by the replenishment pipe 35 as necessary, such as a shortage due to evaporation or the like. Moreover, the water in the receiving part 32 can be appropriately drained out of the circulation system from the drain pipe 36.

  The impurity removing apparatus 1 according to the present embodiment has the above-described configuration. When the processing air is introduced into the chamber 2, dust or the like is removed by the filter 4 and then the gas-liquid contact material 11 is firstly removed. Pass through. Since the surfaces of the corrugated plates 12 and 13 constituting the gas-liquid contact material 11 are always wet as described above, the protrusions 12a and 13a and the grooves 12a and 12b of the corrugated plates 12 and 13 are used. The surface of the air flow path is always covered with a thin film of water, and when the processing air flows through the flow path, it comes into contact with the water on the surface and the soluble gas is absorbed and removed by the water. .

Then, the air that has passed through the gas-liquid contact material 11 is then subjected to inertial collision with the hydrophilic eliminator 21. At this time, since the surface of the plate 22 of the hydrophilic eliminator 21 is also wetted by the water transmitted through the corrugated plate 12 of the gas-liquid contact material 11, the soluble gas in the processing air is held by the hydrophilic eliminator 21. Absorbed and removed by gas-liquid contact with water. Of course, since the hydrophilic eliminator 21 itself functions as an eliminator, it does not receive the liquid droplets scattered from the gas- liquid contact material 11 and scatter them backward.

  The air from which the soluble gas has been removed by the gas-liquid contact material 11 and the hydrophilic eliminator 21 as described above is led out of the chamber from the outlet 7 by the fan 6 as clean air.

  As described above, in the impurity removing apparatus 1 according to the present embodiment, the hydrophilic eliminator 21 itself, which is responsible for preventing the backward droplets and mist from being scattered, also has a soluble gas removing effect, so that the gas-liquid contact is performed. The burden on the material 11 itself can be reduced, and the length of the gas-liquid contact material 11 in the airflow direction can be shortened accordingly. The hydrophilic eliminator 21 is also sufficient to have a minimum water droplet capturing performance, and the pressure loss can be reduced accordingly.

  Furthermore, as for the water supply to the hydrophilic eliminator 21, since a part of the water supplied to the gas-liquid contact material 11 is used, it is not necessary to supply the hydrophilic eliminator 21 independently and its water supply unit There is no need to receive a pump separately. Therefore, the entire apparatus is also compact from this point.

  In the above embodiment, a watering device is used as the water supply unit 31. Instead, a spray nozzle is installed on the upstream side of the gas-liquid contact material 11 to spray water toward the gas-liquid contact material 11. Things may be used.

  Moreover, in the said embodiment, the distance between the gas-liquid contact material 11 and the hydrophilic eliminator 21 so that the downstream edge part of the gas-liquid contact material 11 and the upstream edge part of the hydrophilic eliminator 21 may contact. Was set to 0, but they may be installed with a distance between them as appropriate. That is, as shown in FIG. 7, when the distance between the downstream end of the gas-liquid contact material 11 and the upstream end of the hydrophilic eliminator 21 is L, both are within a range of L = 1 to 50 mm. May be installed.

More specifically,
(1) When supplying water from the top of the gas-liquid contact material 11 and the average air speed passing through the gas-liquid contact material 11 is less than 3 m / s:
L = 2mm or less. However, as the structure of the gas-liquid contact material 11, it is preferable that at least 5 to 10% of circulating water reaches the downstream end side.
(2) When supplying water from the top of the gas-liquid contact material 11 and the average wind speed passing through the gas-liquid contact material 11 is 3 m / s or more:
When the passing wind speed increases, the amount of scattered water from the downstream end of the gas-liquid contact material 11 increases. Therefore, even if the distance from the hydrophilic eliminator 21 is longer than in the case (1), the surface of the hydrophilic eliminator 21 is It becomes hydrophilic. However, since the falling angle of the scattered water (the angle at which it scatters downstream with respect to the vertical direction) is relatively small, L is preferably within 20 mm. If the length is longer than this, the amount of water supplied to the upper side of the hydrophilic eliminator 21 is reduced, and the replacement of water is extremely reduced, which affects the gas removal performance.
(3) When the water supply is sprayed from the upstream side of the gas-liquid contact material 11:
In this case, since a part of the spray water can reach the downstream hydrophilic eliminator 21 without being captured by the gas-liquid contact material 11, the installation interval between the hydrophilic eliminator 21 and the gas-liquid contact material 11 is increased. Is no longer a limitation, but it is still desirable to be shorter when considering compact equipment.

Next, the results when the impurity removal apparatus 1 according to the present embodiment is actually operated will be described.
First, as treatment conditions, the water supply amount L / G (L: mass of makeup water, G: mass of treatment air) per unit treatment air was 0.05, and the treatment wind speed was 2.5 m.
Pressure loss = 105Pa
Saturation efficiency = 95% (Saturation efficiency is an index indicating gas-liquid contact efficiency. The higher this value, the higher the gas removal performance.)
Device size (air flow direction) = 0.3m

On the other hand, each performance disclosed in Patent Documents 1 to 4 is as follows: Pressure loss 200 to 460 Pa (including pressure loss of eliminator) at 2.5 m / s equivalent Saturation efficiency 91 to 96%
Device size (air flow direction) = 1 to 3.5m

  As described above, the impurity removing apparatus 1 according to the embodiment achieves a significant reduction with respect to the prior art with respect to pressure loss and apparatus size. On the other hand, the saturation efficiency is equivalent. Therefore, according to the present invention, it is possible to achieve a reduction in installation space and device cost and a significant reduction in blast power energy and cost.

  The present invention is particularly useful when supplying clean air to, for example, a semiconductor factory or a precision parts factory, because soluble gas is removed and water droplets and mist are not discharged into the processed air.

It is explanatory drawing which shows the outline of a structure of the impurity removal apparatus concerning embodiment. It is a perspective view of the process part in the impurity removal apparatus concerning embodiment. It is explanatory drawing which shows the depression angle of the protrusion part in two types of corrugated sheets. It is explanatory drawing which shows the distance between the rib parts of a corrugated sheet, and the height between a rib part and a groove part. It is explanatory drawing which shows the flow of the water in a 1st corrugated sheet. It is explanatory drawing which shows the flow of the water in a 2nd corrugated sheet. It is a perspective view for demonstrating the distance between a gas-liquid contact material and a hydrophilic eliminator.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Impurity removal apparatus 2 Chamber 5 Processing part 11 Gas-liquid contact material 12, 13 Corrugated plate 12a, 13a Projection part 12b, 13b Groove part 21 Hydrophilic eliminator 31 Water supply part

Claims (7)

A device that absorbs and removes soluble gas in the processing air by gas-liquid contact,
A chamber capable of circulating the processing air from upstream to downstream in the interior;
A processing unit housed in the chamber, having a gas-liquid contact material made of a hydrophilic material on the upstream side, and having a hydrophilic eliminator on the downstream side;
A water supply unit for supplying water to the gas-liquid contact material;
Have
A plurality of corrugated plates made of a hydrophilic material only in the gas-liquid contact material are arranged in parallel in the width direction in the chamber in a vertically standing state, and protrusions and grooves on the corrugated plates are provided. The first corrugated plate directed obliquely downward toward the downstream side and the second corrugated plate in which the ridges and the grooves in the corrugated plate are directed obliquely downward toward the upstream side are alternately arranged. Structure,
A part of the water supplied toward the gas-liquid contact material is directly supplied from the gas-liquid contact material to the hydrophilic eliminator, and is configured to wet the surface of the hydrophilic eliminator. Impurity removal device. The diagonal angle of the ridge and groove in the first corrugated plate is 10 ° to 80 °, and the diagonal angle of the ridge and groove in the second corrugated plate is 10 ° to 80 °. characterized in that there, impurity removal apparatus according to claim 1. The height between the top of the ridge and the bottom of the groove in each corrugated plate is 3 to 15 mm, and the length between the tops of adjacent ridges is 5 to 30 mm. The impurity removal apparatus according to claim 1 or 2 . Characterized in that the upstream end of the downstream end portion and a hydrophilic eliminator of the gas-liquid contact member is in contact, impurity removal device according to any one of claims 1 to 3. The impurity removal according to any one of claims 1 to 3 , wherein the distance between the downstream end of the gas-liquid contact material and the upstream end of the hydrophilic eliminator is 1 to 50 mm. apparatus. The water supply unit is characterized in that it is intended to feed water directly water into gas-liquid contact member from the upper part of the gas-liquid contact member, an impurity removing device according to claim 1. The water supply unit is characterized in that it is intended to spray water into the gas-liquid contact member from the upstream side of the gas-liquid contact member, an impurity removing device according to claim 1.

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