US2589229A - Adsorbing device - Google Patents

Description

March 18, 1952 s. s. DAUPHINEE 21,539,229

ADSORBING DEVICE Filed Aug. 14, 1946 4 Sheets-Sheet l i911. ll-I.

INVENTOR Genrge S. Daupfwne e TTORNEY March 18, 1952 G. s. DAUPHINEE 2,589,229

ADSORBING DEVICE Filed Aug. 14, 1946 4 Sheets-Sheet 2 i7 i5 16 i ii llllV Patented Mar. 18, 1952 UNITED STATES PATENT OFFICE George S. DQ233233??? T assignor,

by mesne assignments, to W. B. Connor Engineering Corporation, New York, N. Y., a corporation of New York Application August 14, 1946, Serial N 0. 690,551

6 Claims. (01. 1ss 4.0)'

; This invention relates to improvements in air conditioning apparatus and the like and more particularly to an improved air recovery device for removing'odorous and adulterating gases or fluids from a re-circulated portion of the surrounding air.

The invention is particularly applicable although, not limited to the process of Continuously extracting accumulated gaseous impurities from used ventilating air in the circuit of an air conditioning system so that this air may be used over again repeatedly. In this manner the high thermal and psychrometric values of the air will be conserved which otherwise would have been wasted because of the presence of these gaseous impurities.

Certain present conditions have created a definite demand for more compact equipment of this type,- that is devices which will purify a greater quantity of air per unit face area and with less resistance to air flow. This requirement applies particularly to systems serving comparatively small areas, suchas the passenger space in railroad cars, busses, aeroplanes and the like where the bulk and the weight of the equipment must be kept at a minimum without decrease of its capacity.

The air purification device to which the present invention is applicable isconstructed along the same principle as that disclosed in my Patents No. 2,214,737, datedSeptember 17th, 1940, and No. 2,303,332, dated December 1st, 1942. It has been found. however, that the space requirement for the device disclosed in the first mentioned patent is entirely too high for the aforementioned type of service even though it has a satisfactorily low resistance to the air flow. On the other hand, the space requirement of the device disclosed in the last mentioned patent might be satisfactory but the resistance to the air flow is too high at the desired rate of flow.

It is. therefore among the objects of the present invention to provide an air recovery device that will meet the aiorement'ioned requirements as to space and weight and resistance to the air flow. Furthermore in the equipment heretofore used the renewal of the carbon in the individual units required separate handling. This would present .a great obstacle in the small and compact device according to the invention. It is, there ore, a further object to provide an air recovery device in which the carbon inthe individual units can be removed and renewed single operation. 1 e

Other objects and advantagesinherent in the invention will become apparent from the follow-- ing specification taken in conjunction with the accompanying drawings which disclose by way of example two different embodiments of the invention.

Referring 'in greater detail to the drawing throughout which the same reference characters are used to indicate the same or analogous parts:

Figure 1 is a top plan view of an air recovery device according to the invention partly in section.

Figure 2 is a front elevation thereof.

'Figure 3 is a section taken along the line 3 3 of Figure 2.

Figure 4 is a section of a modification taken along the line 44.of Figure 6. 5

Figure 5 is a section of the individual carbon canister used in the modification shown in Figure 4and drawn to an enlarged scale. 1 v Figure 6 is a front elevation of the front plate taken in the direction of the arrows li -6 in Figure 4. 4

The device as heretofore indicated consists of a cell or panel comprising several individual carbon containing units. For the'purpose of the. invention, the capacity of this cell should be at least 250 cubic feet per minute per square foot face area of the panel and the resistance to this rate of air flow should not be more than 0.2 w. g. (water gauge). In the conventional devices it has not been possible to reduce the resistance to such a low value and still maintain the capacity mentioned. It is not absolutely necessary however to circulate all of the air through the carbon bed, as the volume of circulation required for air conditioning is based upon other considerations than that of merely extracting the impure gases from the. air. Thus quite satisfactory conditions from an air purification standpoint can be obtained by passing only about of the recirculated. air through the carbon bed and bypassing the other 25%. I

Thepresent invention contemplates therefore an air recovery device having means for letting a portion of the recirculated air by-pass the carbon bed. This by-pass is so located as to discharge into the stream on the downstream side of the porous carbon wall and obviously this arrangement lessens the general resistance consid-' metal or other self sustaining material I I and I2 which are bent in zig-zag or accordion pleated fashion to form a plurality of alternately reversed V-shaped elements which extend between the flanged top casing I3 and the flanged bottom casing I4 and the side members I5 and IS.

The carbon containing cell I0, formed by the sheets I I and I2, is closed at one end by means of the side member I6 which is provided with a pad or gasket I! of rubber or similar material against which are pressed the edges of the metal sheets I I and I2 to provide a tight closure when the device is assembled. The side member !5 may be welded to or otherwise permanently connected to the top and bottom casings I3 and 4.

The other end of the cell formed by the sheets II and I2 is closed by the side member I5, which is detachable and which presses the rubber pad I9 firmly against the edges of the sheets.

The side member I5 may be clamped firmly in position by means of the angle irons I8 which ever, a rectangular cross sectional form has been adopted which normally has little resistance the perforated sheets I I and I2 enclosing the carb on mass may be formed with small circular depressions 21 which are spaced along the sheets, -to suit requirements. The flat bottoms of these depressions register with those of similar depressions in the opposite sheet and are spot welded at point of contact.

These depressions obviously add to the structural strength of the porous member and the reduction in purifying sur- 1 face area caused by these depressions is negligible.

When assembling or filling the cell with carbon, a special screen cover is placed over the open end; that is the end with the detachable cover area providing a plurality of pockets A. As indicated, however, the entire volume of the recirculated air is not passed through this porous area. In order to carry out the objects of the invention, the V-shaped cell may be provided with slots 2I on the intake side or front side of the cell. These slots are preferably located at the bend of the V and are formed by extenslons 22 and 22a of the sheets II and I2 respectively which are welded or otherwise attached to one-another to provide flared openings for the slots 2 I. The gap or opening of the slot is maintained at the desired width by means of the spacer members 24 which are spot welded or otherwise connected intermediate the extensions 22 and 22a at predetermined intervals.

It has been found that with an air flow of 250 cubic feet per square foot face area and a resistance of 0.2" w. g. the width of the gap should be about 1% of an inch.

The sheets II and I2 which form the porous element defining the pockets A are spot welded or otherwise joined at the rear or exit side of the cell at the extreme ends of the extensions 25 and 26 of the sheets II and I2 respectively. Because of the thinness of the sheets, these joints are. pliable and therefore can act as hinges to allowv a variation of the space between the slots 2| The aforementioned space may be varied within the limits to suit the dimensions of the panel as dictated by space requirements. For example, if the cell dimensions were 24 inches and the number of pockets I6, the space between the slots would be 1.50 inches. On the other hand, if thecell dimension were 20 inches and the number of pockets I3, then the spacing would be 1.50 inches.

It will be understood that the alignment bars 20 can be stamped to suit any desired spacing.

I5. The cover is so made that the carbon space is open and the pocket space is closed. The cell is'now dropped into a box, a few inches taller than'the cell and open at the top, into'which it fits closely. Carbon can now be poured over the top of the cell and the carbon space of the perforated elements so filled. The rubber pad l9 isnow placed over the open end and then the cover I5 is placed over this and pressed down so that the edge of the element metal penetrates into the surface of the rubber pad.' The cover I5 is then bolted in place and the cell is complete, It will thus be readily seen that the assembling, filling and replacement of carbon can be accomplished without handling of the individual elements. I

Assuming now that the air capacity of the cell or panel shown, to meet the demand, is at least 250 cubic feet per square foot face area of panel, 75% of this enters the pocket andpasses through the porous activated carbon wall forming the said pocket, 25% passes through the by-pass" indicated. The preferred air velocity through the porous wall is feet per minuteand the overall resistance to air flow is 0.2" w. g. Since velocity varies as the square root of the pressure and since according to the standard formula the square root of l" w. g. pressure corresponds to a velocity of 4005 feet per minute under standard air conditions, the air velocity through the by-pass is 4005 4072"": 1790 feet per minute. Due to this high velocity, the width of the slot comprising the by-pass is small, being in the order of 1 5". It is obvious that the capacity per square foot of face area could be in.- creased by increasing the depth of the cell in the general direction of airflow. thus increasing the width or area of the porous wall. This however,

would cause an increase in the air velocity A standing vertically, the carbon would, due to the excessivevibration, settle to the lowerportion and no container except a truly circular one would i withstand the bulging action produced by -,.the

through the space between the pockets A and thus increase the overall resistance. From my experience in the-service mentioned.abo'v'e', the above width of the porous wall should be preferably not more than 4 and. the :rateof air flow per square foot face area-250-feet and resistance not more than 0.2" w. g. With theserequirements, the design is predicated on passing through the carbon and 25% through the by-pass, constituting the entire air circulated. as previously stated, the; volume of en wall and lessens the general resistance as the;

effect of this by-pass is to promote air fiow through the porous wall in the general direction of air flow. 2 The equipment covered by Patent No. 2,303,332

at the same capacity as the cell above described has a resistance of 0.55" w. g. or 275% greater than the new cell. The resistance of 0.55" w. g. is not practical for the services mentioned. I Referring now to the modification illustrated in Figures 4 to 6 the panel or cell comprising a. casing defining a rectangular enclosure, a front plate32 and a rear'plate 33 and a plurality of conical carbon containing perforated canisters 34 which are assembled between the plates 33 and 32.

The rear plate 33 is provided with spaced circular openings 35 to receive the base projection 36 of the canister 34 into which it fits snugly. This rear plate is in fixed assembly with the casing 3| by means of the flange 31 which is spot welded or otherwise securely fastened to both the casing 3| and the plate 33.

The front plate 32 is in construction similar to plate 33 except it is detachable by means of bolts 38. The top plate is provided with spaced circular holes 39 to receive the top of the canisters 34 and they are concentric with the holes 35 of thebottom plate. It is also provided with holes 41 (see Figure 6) located between the holes 39 to admit the air to be purified.

The canister comprises an outer conical casing 34a and an inner conical casing 341). These casings are concentric and the intervening space 4| is of uniform thickness throughout. This spacing is maintained by means of the bottom closure member 42 and the upper closure member 43. In addition to closing the space 4|, the lower member 42 is provided with a flange extension 44 to" reenforce the end 36 of the conical casing 341) which projects through the opening 35.

In the case of the top closure 43 this is provided with an outstanding flange 45 which in cooperation with the top plate 32 serves to lock the canister 34 into fixed position. It will be further noted that this closure is provided with a central opening 46 for the purpose explained later.

The conical casings 34a and 34b are perforated and can be made of any suitable sheet material, preferably tinplate 0.010" to 0.015" thickness. The space 4| is filled with granular activated car. bon and the canister vibrated to completely pack the granules so that no serious further settlement will occur when the cell is in service.

The cell or panel is positioned into the air circuit passage or duct so that the air to be purified will transverse it, entering through the hole 41 in front plate 32 and leaving through hole 35 in rear plate 33. To be more specific, the air path is as follows: It enters through holes 41,

thence passes through the perforated conical casing 34a, thence through the porous carbon mass in the space 4|, thence through the perforated conical casing 342) and thence outward through the open base of the conical canister. In passing through the carbon mass, the gaseous im- 6 purities contained in the air are adsorbed and retained by the action of the activated carbon.

Air also enters the opening 46 in the closure 43. This quantity of air is approximately 25 of the total quantity passing and is not purified. As previously indicated, the purification of approximately 75% of the air in the circuit of an air conditiong system, I have found to be suflicient and most practical as the cell or panel now occupies only 75% of the space it would otherwise occupy if 100% of the air were purified, which, as stated above, is not necessary.

This cell illustrated has been designed for total capacity of 250 cubic feet of air per square foot face area of the defined rectangle. 75% of this is purified and 25% is by-passed as above explained. The resistance to air flow at the above capacity is not more than 0.2" w. g. Accordingly, it satisfies the present demand as outlined and accomplishes the main object.

Like the embodiment in Figures 1 to 3, in this conical canister type provision is also made to fill the canister with carbon and to renew "the carbon without handling the individual canisters separately. The procedure when renewing the carbon is as follows:

' Plate 32 is removed, also end closures 43. An-

other plate (not shown) similar to plate 32 but with the air access holes omitted is now substituted for plate 32 and bolted in place. The top carbon space exposed and open. The cell may be tippedover to allow the carbon to flow out into any suitable container. For refilling, the cell is now set down with the plate upward. The holes 46 are fitted with any suitable plugs or otherwise closed in any suitable manner. Carbon is now poured over the top area and the 'canisters so filled. When. filled and vibrated to complete settlement, the plugs and the extra plate are removed and the regular plate 32 put back and bolted up. The cell is now ready and complete for use.

In this type, the carbon canisters being circular, there is no anxiety in regard to distortion or bulging due to carbon settlement.

The smaller the diameter of the cones chosen the greater will be the carbon wall area obtainable in any given rectangular area. I have by preference chosen approximately 3" for the major diameter. These are suitable for rectangles 2'7", 24", 21", 18", 15" and 12", as all of these lengths are exactly divisible by 3. 20" and 16" are quite popular. Accordingly, for

20" the diameter of the cone would be approximately 2%" and for the 16" the diameter of the cone would be approximately 3 For the width of carbon space between the cone wall, I have chosen as experience has shown this to be about correct for the service outlined. A greater thickness of bed would, of course, give longer life but the thicker the bed the greater the resistance to air flow. Accordingly, the bed and 0.2" w. g. resistance, I have found to be a good compromise.

It should be understood that this disclosure is given by way of example and not by way of limitation. 0n the other hand, the invention lends itself to a variety of expressions within the scope of the appended claims.

What is claimed is:

1. A device for adsorbing adulterants comprising a casing having an intake side and an outlet side for permitting circulation of air therethrough, a series .of'hollow. adsorbing elements extending between the'inlet side andgthe outlet side-ofsaid casing, the-adsorbent'wall members of said lhollow elements convergingtowards the intake-side of. said casing, each'of'said elements having an enlarged outlet opening adjacent the outlet side of said casing and a restricted inlet opening-adjacent the intake side of said casing whereby a portion of the air circulated through said device will be jetted through said hollow elements.

2. A device for adsorbing adulterants having an intake side and an outlet side for permitting circulation of 'air through said device, comprising an adsorbing element penetrable by the circulated air and having side walls converging towardsthe intake side of said device and defining an intermediate space, said element'having a-restricted inlet opening adjacent the-intake side of said device and an enlarged outlet opening-ad'- jacent the outlet side of said device, whereby a portion of the-air circulated through said device will be jetted through said elementsl 3. A device foradsorbingadulterants having an intake sideand'an outlet side for permitting circulation of air through said device,-comprising an adsorbing element penetrable bythe circulated airand having side Walls converging towardsthe intake side of said device and defining an intermediate space, said element having arestricted inlet opening adjacent the intake side of said-device and an enlarged outlet openingadjacent the outlet side of said device, whereby a portion of the air circulated through said device will be jetted through said elements, and means for varying the degree of slant of said convergingwalls.

, 4'; A device for adsorbing adulterants having an intake side and an outlet side permitting circulation of air through said device, comprising an adsorbing element penetrable by the circulated', air and extending in zig-zag formation across said'device defining a plurality of intermediate alternately reversed triangular shaped pockets, said element having an inlet opening in the bends adjacent the intake side of said device-.- sai d;inlet opening-beingrestricted with. re? spect-to-thebaseof said pockets, whereby a pore tionof the: air, circulated throughsaid device will be jetted through-said elements.

5. A device for adsorbing adulterants having an intake side and an outlet side permitting circulation of air through said device, comprising an adsorbing element penetrable by the circulated air and extending in-zig-zag formation across said device defining a plurality of intermediate alternately reversed, triangular shaped pockets, said element having an inlet opening in thebends adjacent the intake side of said device, said-inletopening being restricted with respect to the base of said pockets, whereby a portion of the air circulated through said device will be jetted through said elements and hinge means atthe bends of said adsorbing element adjacent the outlet side of said device for varying the width of said pockets.

6. A device for-adsorbing adulterants having an intake side and an outlet side for permitting circulation of, air through said device, comprising a conically shaped hollow adsorbing element defining an annular space, said element having an enlarged outlet opening adjacent the outlet sideof said device and a restricted inlet opening adjacent the intake side of said casing, whereby a portion of the air circulated through said device'will be-jetted through said elements.

GEORGES. DAUPHINEE.

REFERENCES CITED The following references are of record inthe file of'this patent:

UNITED STATES PATENTS Number Name Date 1,863,578 Morse ,et al June 21, 1932 2,075,036 Hollis Mar. 30, 1937 2,214,737 Dauphinee Sept. 17, 1940 2,303,332. Dauphinee Dec. 1, 1942 2,303,334 Dauphinee Dec. 1, 1942 FOREIGN PATENTS Number Country Date 257,879 Great-Britain Jan. 24; 1927

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