US 2491645 A
Description (OCR text may contain errors)
Dec. 20, 1949' A. R. CLARK E L APPARATUS FOR WASHING AIR Filed Nov. 23. 1944 James C. Buck LQIQOa/v ATTORNEY Patented Dec. 20, 1949 UNITED STATES PATENT OFFICE APPARATUS FOR WASHING AIR Albert R. Clark and James C. Buck, Toledo, Ohio, assignors to The De Vilbiss Company, Toledo, Ohio, a corporation of Ohio Application November 23, 1944, Serial No. 564,818
This invention relates to an improved apparatus for washing air to remove dust and other suspended particles arising from industrial operations such as paint spraying, grinding and polishing.
A principal object of the invention is to provide improved means for introducing water into the air to be cleaned.
Another object is the provision of means for more effectively and rapidly separating the water from the air after the foreign particles have been caught by the water.
A further object of the invention is to provide a washing chamber in which the baflles and guides are mounted so that they may be readily removed for cleaning purposes and may be easily placed back in operating position.
More specifically this invention relates to an air washing apparatus in which a blower or fan creates a strong current of air through the waterwash chamber and the velocity of the air is utilized to disrupt the surface of the water in the water tank and draw the water into the air. The particular structural feature, which is mostly responsible for the superior results obtained, is
the water pick-up bar comprising a horizontally extending rectangular plate with its principal surface in a vertical plane. This bar is positioned across the air entrance to the waterwash chamber and, when the apparatus is ready to function, its bottom edge is substantially level with the top of the water in the water tank which forms the base portion of the apparatus.
When the blower or fan is put in operation and pulls air through the waterwash chamber, the pressure therein is reduced below atmospheric and this causes the water level in the section of the tank immediately below the chamber to rise and the level of the water outside of the chamber beyond the water pick-up bar to drop proportionately. This tends to form a narrow opening between the bottom edge of the bar and the receding water surface, and there is created a turbulent rise or wave of water just beyond the bi bar, marking the juncture of the two water levels. Air rushing beneath the bar strikes against this wave and carries away a portion of it. Water continues to surge toward the bar to fill in the wave and thus continues to meet and mix with the low, upwardly into confluence with the upper air; and the combined streams of air then travel together into the waterwash chamber. Cons-iderable water is drawn into the air in this apparatus and the water is so well broken up and dispersed that a thorough washing of the air is obtained.
Other supplemental features as well as additional objects and advantages will be more fully apparent from the following detailed description with reference to the accompanying drawings in which:
Figure 1 is a vertical sectional view of the apparatus embodying the invention; and
Figure 2 is a fragmentary perspective view of a portion of the apparatus showing one end of the water pick-up bar and its supporting bracket.
In the drawings the main waterwash chamber l is positioned above a water tank 2. To maintain the water at the proper level in the water tank 2 a water inlet 30, controlled by float valve assembly 3 I, is provided. At the top of the waterwash chamber is an outlet adapter 3 from which the air flows through duct 4 to blower 5. The blower is driven by motor 6 with belt 1. The blower 5 and motor 6 are mounted upon platform 8 which is supported principally by rods 9, only one of which is illustrated.
As indicated by large dotted arrows, the air to be cleaned is drawn into the entrance I!) of the apparatus and flows past, both over and under, the water pick-up bar II, which is positioned just above the normal surface level of the water in the tank 2. A major portion of the air travels above the bar I I as the'opening there is much larger than that below the bar. The bar I! is adjustably mounted by means of bolts [2 to brackets [3 which are welded to the sides of the tank.
With the water (the movement of which is indicated by small solid arrows) that is picked up by the air in passing under bar II, the air proceeds with considerable velocity through the narrow horizontal passage formed between the surthe air, the water travels laterally from the forward edge I! of guide IS with considerable force and a major portion of the water strikes against guide 18. This portion of the water then drops downwardly and flows across the top of partition Id, at the edge of which it is again picked up by the upwardly flowing air current.
The balance of the water that does not impinge against guide 18 ,moves .upwardly with the air and, as directed by guide l8a, turns with it above the end ll of guide l6. Through the effect of the subsequent reversal of the air flow caused by guides l9 and I9a, most of the water remaining in the air is here precipitated and flows down the rear side of guide I6 and :betweenguide l5 and the rear wall 20 of the water chamber back into the water tank 2.
In its further journey upwardly through the waterwash chamber, the air is divided into two channels by guides 21 and 22 which together make a rather fiat V across the waterwash chamber. The portion of the air directed by .guide'fi strikes against therear wall 20. In this impingement most of zthe small amount of water remaining in the air ,is separated therefrom and flows down wall 20 .over bafilc .23 upon guide 19a and then downwardly between guide l9 and wall 20 and hence between guide l5 and wall 23 into the water tank.
There is no air movement in the lower p r ion of this path as its end isclosed Off by the Water and there is little air movement through the hppersection of the path due to its restrictive dimensions.
The portion of the .air directed forwardly by guide 2! strikes against the forward .Wall 24. This impingement extracts water still carried by the air and such water runs down wall .24 .over baiile 25 upon guide .1811. and through the narrow passage formed between guide 18 and Wall 24.
,By this path it avoids being carried .along with cau ht y the T baffle '26 or the side ,bafiles 21 and 28. This water will .dropinto the V formed by guides 2| and 22 and down th ou h the op ing between them. It then may become again entrained in he air and prec pita ed agains either the front or rear wall of the chamber.
It is apparen t e efore, hat wat r sep at from the air in the middle and upper sections of the waterwash chamberv flows downwardly along the rear .and forward walls 26 and 24, and bypasses the path of the main stream of air during most, if not all, of its downward travel.
In this manner it avoids the upward pull of such air. In previous waterwash apparatus of this general type, the water separated from the air after the washing phase must pass through the main body of moving air in returning to the Water tank.
As a result, some of the water is repeatedly picked up by the air and carried further along with it. For this reason more extensive separating baffles or eliminators are required to finally remove all water from the air. apparatus larger and more costly.
In the center of applicants tank below the surface of the water is a transverse plate 29 extending across the tank on three angle iron bars. It serves to prevent a pulsating surge of water This makes the in the water tank that otherwise develops during the operation of the apparatus. The exact position and shape of this plate may be altered considerably without affecting the results secured.
In order that the waterwash chamber and water tank may be eas ly cleaned, doors 32 and 33 hinged respectively at 34 and 35, are provided at theilower ends of the walls 20 and 24. Also, the various guides and baffles are so mounted on angle iron brackets welded to the sides of the .ohamber that they may be easily removed. Most of these brackets are formed of small angle iron segments-with one leg lying flat against the side wall and the other extending therefrom to act as a shoulder upon which the end of the guide or :baffie may set or be bolted. Such brackets are also used to hold the guide from being thrust upwardly by the air movement. In order to secure them more firmly in place the vertical guides are provided with hooks which extend over the brackets. Some of these brackets are indicated as 3.6. Other brackets 3'! are angle iron bars running across the width of the chamber.
While water is referred to herein as the c1eaning medium, other liquids such as a mIneral oil might be more suitable under certain circumstances. As little, if any, change would be required to adapt the apparatus to other cleaning liquids, this invention should not be considered as restricted to the use of water. Likewise, it should not be considered as restricted to the washing of air as it would be equally as effective in cleaning other gases.
'It may be seen from the foregoing that the invention provides a simple but decidedly effective apparatus for washing air. While a particular embodiment of the invention has been presented, it is obvious that the design and position of the water pick-up bar maybe considerably modified Without departing from the spirit of the invention. Similarly, changes may be made in regard to the return passages for the water which avoid the main stream of air, as well as in the turbulence preventing plate 29 without going beyond the scope of the invention.
Having thus described this invention, we claim:
1. In an apparatus ,for washing air, a water tank, a passage for the air to be cleaned including a portion of said tank just above the surface of the water in the tank, a narrow transverse member dividing said passage horizontally across its lower portion and checking the air flow sufficiently to cause an appreciable drop in pressure beyond the member, the member being spaced to permit a slight opening beneath it for the flow of air, the difference in pressure on either side of the member causing the water level to be higher just beyond the member, so that the air passing beneath the member strikes against the eddying rise of water between the two Water" levels, and a horizontal extension of the air passage immediately beyond the transverse member where the air passing above and below the member unite in a common stream.
2. In an apparatus for washing air, a water tank, a waterwash section, means for causing the air to flow through the waterwash section a passage over the surface of the water in the tank for the air travelling to the waterwash section, a transverse bar across the lower portion of the passage near the air entrance momentarily splitting the air flow horizontally and directing the lower portion of the air into commingling relation with the water, and horizontally extending baffle means below the surface of the water beyond the transverse bar to reduce turbulence of the water caused by the movement of the water into commingling relation with the air.
3. In a waterwash apparatus, a water tank, a vertical chamber above the tank the chamber having front, rear, and side walls, means for guiding water-charged air upwardly through the chamber including a bafile member extending from one side wall to the other side wall of the chamber and spaced slightly from the rear wall of the chamber, a main portion of the baflle being parallel with the rear wall and defining a narrow vertical passage therewith, an upper section of the bafile inclined upwardly and forwardly from the parallel portion, and means above the inclined section for removing water from the air and dropping it upon this section from which the water flows down between the parallel portion and the adjacent wall and back to the water tank.
4. In an apparatus for washing air, a water wash chamber in which the water and air are thoroughly mixed together, a passage for the air to be washed leading to said chamber, means for rapidly drawing the air through the passage and the chamber, a tank for water associated with said passage, the surface of the water forming a substantial portion of the lower wall of the passage the upper wall of the passage including a vertical- 1y declining section, and a vertically fiat transverse member rigidly positioned across the passage extending a short distance upwardly from the water whereby the velocity of the air passing over the upper edge of the transverse member creates a vacuum behind the member to draw water upwardly into confluence with the air.
5. In an apparatus for washing air, a water wash chamber, a guide member positioned across the chamber for directing the air in a tortuous path, a pair of opposed brackets on opposite walls of the chamber providing inclined ledges upon which the ends of the guides are supported, a laterally extending hook on each end of the guide going over the upper end of the respective ledge to prevent the guide from sliding sideways down the inclined surface, and a second pair of 0pposed brackets on the same opposite walls setting against the upper sides of the ends of the guides to prevent the latter being raised by the upward force of the air stream.
6. In an apparatus for washing air, a water tank, a horizontal passage for the air to be cleaned including a portion of said tank just above the water in the tank, means for causing the air to flow through the horizontal passage, a narrow transverse member lying across the lower portion of said passage and checking the air flow therethrough sufficiently to cause an appreciable drop in pressure beyond the member, the member being spaced to permit a slight opening beneath it for the flow of a portion of the air, the difference in pressure on either side of the member causing the water level to be higher just beyond the member, so that the air passing beneath the member strikes against the eddying rise of water between the two water levels, and an extension of the air passage immediately beyond the transverse member where the air passing above and below the member unite in a common stream.
ALBERT R. CLARK. JAMES C. BUCK.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 1,214,114 Andrews Jan. 30, 1917 1,842,663 Ellis Jan. 26, 1932 2,119,207 Gibbs May 31, 1938 2,120,490 Drummond June 14, 1938 2,167,839 Henderson Aug. 1, 1939 2,171,574 Lambert et al Sept. 5, 1939 2,259,626 Erikson Oct. 21, 1941 2,373,330 Nutting Apr. 10, 1945 2,379,795 Fenn July 3, 1945 2,383,138 Ludwig Aug. 21, 1945 2,395,960 Clark Mar. 5, 1946