US2138684A - Drying and cooling apparatus - Google Patents

Description

Nov. 29, 1938.

E. A LTENKIRCH DRYING AND COOLING APPARATUS Filed Feb. 17, 1954 Patented Nov. 29, 1938 PATENT oFFicE l2,138,684 DRYING AND COOLING APPARATUS Edmund Altenkirch, Neuenhagen, near Berlin, Germany Application February 17, 1934, Serial No. 711,673 In Germany February 24, 1933 19 Claims.

This invention relates to air conditioning apparatus and more particularly for means for cooling and drying air.

It is well known that silica gel, charcoal, certain kinds of wood, and other substances have the properties of absorbing water or other refrigerating uids at one temperature and discharging the water or uids at a higher temperature. It is also known that certain liquids such l@ as sulphuric acid, lye solution, calciiun chloride solution, etc., have the property of absorbingmeans for removing water from air by an inexpensive and simple apparatus.

It is still another object of the invention to provide air conditioning apparatus which may be operated at low temperatures and thus utilize the heat of the sun for operating it.

3 Other objects and advantages reside in certain novel features of the arrangement and construction of parts as will be apparent from the following description taken in connection with the accompanying drawing in which:

Figure 1 is a fragmentary cross-sectional view of an apparatus for removing moisture from the atmosphere or from other gases which may .be circulated through it, the apparatus illustrating one embodiment of the invention, and

Figure 2 is a fragmentary view of a dwelling house with the wallsshown in cross-section and with another embodiment of the invention incorporated therein which is adapted to dry and cool the air in thevhouse.

f Referring to the drawing in detail and first to the embodiment of the invention shown in Figure 1, the apparatus is shown as consisting of a vertically extending rectangular structure designated at i@ and consisting chieflyv of insulating 5G material, the east and west walls of which have vertically extending rectangular chambers as indicated at il and I2.

Centrally located in the structure I0 is a third vertically extending chamber which may be of 55 any shape, either rectangular or circular as shown nected to the outlet pipe 26.

at I3. This chamber i3 is connected at the top to chimney I4 and, at the bottom to an opening I5, the opening I5 connecting the .chamber I3 to the atmosphere on the north side of the structure. An electric motor I6 and a fan I'I are located in the lower portion of the chamber I3 andv provide means for forcing air upwardly through the chamber I3, the air entering through tige opening I5 and leaving through the chimney lo To prevent the sun from heating the insulating structure I0, a roof i8 may be proyided and air may be circulated thereunder if desired.

Each of the east and west chambers II and I2 constitutes `an absorber-generator and is provided witha number of pans or cup-shaped baffles, those in the east chamber il being' designated i9, and those in the west chamber I2 being designated 26. These cups or pansare' partly filled with a substance such as silica gel, or cal- 2o cium chloride solution, or other substance adapted to absorb water out of the atmosphere if maintained at reasonably low temperatures.' VIf designed for use with solid absorbents, the pans are preferably perforated. staggered between the cups i9 and 2li are a number of baiiie plates indicated at 2i which serve to direct air over lthe pans and in contact with the absorbing substance thereon as air circulates through the apparatus.

The upper ends of the chambers il and I2 30 v are connected together by means of the gas conduit 22. This gas conduit extends into the cham'- bei,` i3 in which it passes downwardly to form a U- bend 23, which is connected by means of the T- connection 2d with a pipe 25. The pipe 25 serves 35 as a water-reservoir and has its lower end con- The pipe 26 may be provided with a faucet, or may drain into a suitable receptacle to collect water supplied to the reservoir 25 by the apparatus. 40

The lower end of each of the chambers II and i2 are connected to the atmphere by means of the gas conduits 21 and 28. Screens or filters (not shown) may be provided in the conduits 21 and 28, to prevent the entrance of insects into 45 the apparatus. If desired the conduits 21 and 28 may be connected to a suitable air pump or a fan for forcing a draft of air through the apparatus.

Since the outer walls of the east and west chambers Il and l2 are made of metal, it will be seen that on a sunny day, heat will be transferred from the sun to the air and to the absorbing ma- 'terial in the east chamber il in the morning and to the air and the absorbing material in the west hereinafter.

chamber i2 in the afternoon.. Other heating devices might also be employed in this apparatus but are not illustrated for the sake of simplicity herein but are shown in the arrangement of Figure 2. It is tol be understood, however, that the arrangement of Figure l is not limited to the use of the heat from the sun alone to operate it.

Assuming that the plates or trays I9 and 2Il of the apparatus of Figure l are lled with' silica gel the apparatus may be operated to remove moisture from air as follows: In the morning the sun will .shine upon the outer wall of the east chamber Il while .the west chamber I2 will be in the shade and at a lower temperature. This will cause the air in the east chamber Ill to have lower density, and, assuming that the pipes 21 and 28 are open to the atmosphere air will rise in the east chamber Il, pass through the conduit 22, which will be maintained at a lower temperature than thatof the chamber Il by the air current set up in the chamber I3. From the conduit 22 the airwill ow downwardly through the west chamber I2 and leave the apparatus through the pipe 28. The air will now in this direction all morning and since the east chamber II is quite warm moisture will be'given up from the silica gel on the pans I9 to the air. This air having a higher moisture content as it enters the gas'conduit 22 than the air entering through the conduit 21, will drop some of its moisture as-it is reduced to the temperature of the atmosphere in the inner chamber I3 of the apparatus. During the initial cycle of the apparatus it may be that there will be little or no condensation in the pipe 22 but as the cycle is repeated condensation in this pipe Will increase -as will be apparent from the description Even during the starting cycle, however, the air entering the conduit 22 will have a higher moisture content .than that entering the chamber I l through the pipe 21.

As the air passes downwardly through the west chamber I2 its moisture content will be reduced due to the absorption of moisture by the silica.

gelI on the trays 20 and thel air leaving the apparatus through the conduit 28 will have a lower moisture content than that entering the apparatus through the conduit'21, the difference being that which has condensed lin the conduit 22.

As the sun passes the` meridian it willv not shine on either the east or on the west walls of the apparatus and air ,circulation therethrough will cease temporarily. In the afternoon the sun will shine on the west chamber. I2. Air will then circulate through the apparatus entering in through the gas pipe 28 passing upwardly through the west chamber I2 through the gas conduit 22 and downwardly through the east chamber II. The silica gel in the west chamber I2 which became highly saturated with water vapor during the morning, now gives up its moisture to the air and as the temperature of the air in pipe 22 is reduced in chamber I3, a large part oi' the water vaporv condenses in the conduit 22 and collects in the reservoir 25.

Likewise the air which ows from pipe 22 into the east chamber I I now has a higher water vapo` pressure than that which enters the west chamber I2 in the morning and the silica gel on the trays I9 become even more saturated than the gel in the trays v20 did in the morning. Nevertheless the air leaving the apparatus through the conduit 21 is in a dryer state than that entering the apparatus through the -conduit 28. From then on, if the quantity of gel in the apparatus and the quantity of air owing therethrough are properly proportioned, water will be retained in the apparatus at each period of operation.

Since heat is being discharged into the air in the inner chamber I3 'of the apparatus a natural draft may be created which will be suicient to cool the gas conduit 22 and cause condensation therein. In this way the apparatus could be operated without the use of moving parts. The use of a motor driven fan as shown in I'I is preferable, however, in that it maintains the gas conduit 22 at a lower temperature.

It will be seen from the above description that means has been provided for using the heat of the sun for obtaining a supply of water from the air. It is also apparent that the apparatus may be operated to cause the heat of the sun to dry air for bringing comfort to human beings or for other purposes and that the drying process may take place without the use of moving parts. The pipes 21 and`28 may be connected to the room in which it is desired to maintain air at a low relative humidity and the conduits 21 and 23 may be connected through various known valve systems and to blowers or fans in such a way that air may be nearly continuously supplied to a chamber at a relative humidity lower than that of the air entering the apparatus. Conversely, assumingl that it is desired to raise the humidity in a room, the conduit 22 might be connected to the room in such a way that it would add moisture yto the air. 'I'hus if chamber I3 were sealed from the atmosphere at the top and bottom, and the pipe 22 were cut oi at the point of entrance into chamber I3, the humidity of the air in the room I3 could be maintained high by operating the apparatus as 'described above. Thus the apparatus o1' Figure 1 may be adapted to condition air in various ways.

Another way of utilizing the principles of the invention to condition air of a dwelling'house or the like is illustrated in Figure 2 in which the arrangement is such that not only the humidity but also the temperature of the air may be changed.'

Referring to the arrangement of Figure 2 in detail it will be seen that a dwelling house is there indicated as havingv an east wall 30 and a west Wall 3|, these walls being shown in cross-section Y and being constructed of heat insulating matethrough opening 35.

'I'he chamber 32 is connected to the room vof the dwelling house by two dampers or doors, the

damper 31 being above the humidifying appa` ratus and opening into the room,v and the-damper 38 being below the humidifying apparatus and opening into the chamber 32. Likewise the chamber 33 is provided with similarly arranged dempers 33 and 40.

Outside o1' the east wall 30 oi'I the dwelling house an absorbing chamber is formed as shown at 4| by means of the vertically extending metallic structure 42. 'I'his chamber contains a number of pans or trays as indicated at 43 adapted to contain calcium chloride or silica gel or other absorbing material, the arrangementr shown having a solution of calcium chloride on the upper three of the baille trays 43, with silica gel on the lower five of these trays. The use of two absorbents in each chamber, which is one feature of the invention, permits absorption toa high degree, because the absorbents will absorb the water vapor at different partial pressures.

For heating the chamber 4l in addition to heat which may be conveyed through the wall 42 of the chamber from the sun, a chimney or heater lll is provided. This chimney also provides means for supportingv thebaiiie plates 65 which serve to direct air passing through the chamber il over the al: sorbing substances on the trays t3. Below the chimney t@ a horizontally extending passage All may be provided and this passage may contain a gas heater, air for combustion being supplied to the heater from the outside by any suitable means. This articial heating means need not be used all the time, but may be used as desired.

The upper end of the chamber il may be connected to the atmosphere or to any air circulator such as a fan by means of the air conduit 8. mie lower end of the chamber il is connected to the chamber 32 in the wall 3d by means of an air passage i9 in the wall 3u.

The arrangement on the outside of the west `wall 3l o the house is exactly the same as that -on the veast side, a chamber 5i being formed by an outer metallic wall 52, the chamber 5i having a number of trays b3 for supporting absorbing material. A chimney til is provided and supports baie plates 55. The chimney Ml is heated by a heater in a horizontally extending conduit 5l. The upper end of chamber 5i is connected to the atmosphere or a fan (not shown) by pipe 53. The lower end of the chamber 5l is connected to the chamber 33 in the wall 3l by means of the air passage 59 in the wall 3i.

I The conditioning of the room in the dwelling is eected preferably automatically by the sun. it

can, however, be eected artificially and perio'dically by alternately heating the chambers ll and 5i. Assuming that it is desired that the apparatus be used to lower the humidity or cool the air in the room and that the apparatus is operated by the sun only, the operation is as follows: in the morning the sun shines against the wall l2 on the east side of the house and the contents of the chamber il are heated. Circulation of air is thus produced by' convection. II'he air enters through the conduit 58 on the west side of the house goes downwardly through the chamberbl, rises in the conduit 59, enters the room after going through the chamber 33 and across the humidier therein, passes through the opening Aat the top of the chamber 33, the damper to being closed at this time. After flowing through the room the air flows downwardly through the conduit t@ in the wall 30, the damper 38 then being open and enters the chamber Ill on the east side of the house, passes upwardly therethrough and leaves this chamber through the conduit t8. The west side of the house being cool and the east side warm during this portion of the cycle,

the humidity of the air in the chamber 5l is de# downwardly through the chamber 5i is lowered to such an extent that as it .passes into the chamber 33 it has a temperature of 35 degrees C. and a dew point of C. This air may be cooled to a temperature of 20 C. by contact with the wicking 36 in the chamber 33 while the dew point of the air is raised to 14 C. By changing theposition of the shutters 39 and 40, the temperature of the air entering the room can be raised and the dew point lowered. For example, if the lower shutter 40 is opened only a small amount the air in the room may assume a temperature of 25 C. while the dew point becomes about 10 C. In operating the apparatus of Figure 2, the direction of air circulation is reversed periodically in synchronism with the heating periods. Where convection alone is usedY to cause circulation of the air, the synchronism of air and heating periods is automatic, the heating of chamber di causing circulationA of air in the direction just described and the heating of chamber l causing circulation in a reverse direction.

When operated by the sun, circulation of air eiected by convection ceases as the sun passes the meridian. In the afternoon when the sun shines upon the west side of the house so that the direction of circulation of air is reversed, the air enters the apparatus through the conduit d8, passes downwardly through the chamber @l and into the room through the chamber 32 in the wall 33. In general, it should be said that during this portion of the cycle the damper 3l should be open and damper 38 closed, while the damper v39 is closed and damper @il open. Air then leaves the room through the damper d, passes downwardly through the passage 59 and upwardly through the chamber 5|, leaving the apparatus through the conduit 58.

inasmuch as the absorbent material in chamber il became very dry during,r the morning, due to the fact that it was heated, the air -now entering the chamber 32 will be even dryer than that which enters the chamber 33 in the morning.

l'n the afternoon the air entering the room may be cooled by means of the humidifier 36 and its associated apparatus in the chamber 32 just as it was cooled by the'humidier in the chamber 33 in the morning.

It will be seen that when operated in this way the apparatus provides means for drying and cooling airsupplied to a room, and on warm summerdays when the sun is shining the air may be conditioned by means of the sun alone. It will also be sean that it is possible to air condition a room without the use `of moving parts, the air being circulated through the room merely by convection currents. It is to be understood,.how ever, that. it is within the purview of the invention to cause the air to circulate in the directions indicated above by usingfans or blowers. It is also contemplated to promote circulation in the desired direction under the pressures created by wind blowing around the house, as for example, across the roof. The conduits i3 and 58 may be connected to funnels or vents on the roof so positioned as to create the desired draft through the house depending upon the direction and magnitude of the wind. Due to the provision of the heaters il and 57 the apparatus can be operated without utilizing the heat of the sun and the period of heating or cooling of the chambers il and 5! can be varied as desired.

It is also possible to use the apparatus of Figure 2 to raise the humidity of air entering the room by causing the air to circulate in the opposite directions to those given above. Thus if the air is circulated, `by means of a fan or the like l the room, downwardly through passages 32 andl 49 and upwardly through chamber 4i, while the invention to so construct the chambers iland 5l as to permit them to be slowly turned so as to face the .sun and thus operate at maximum eiciency.

It is also contemplated to place the conduits conveying air into and out of the room in heat exchange relation so as to increase the effectiveness of the apparatus.

While the apparatus has been explained in connection with the conditioning of air, it is obvious that other inert gases could be conditioned thereby and absorbable constituents other than water removed therefrom. n

Various other changes in the arrangement and construction oi parts may be made without departing from the spirit of the invention or the scope of the annexed claims. j

I claim:

l. Apparatus for conditioning the air in a room comprising two chambers, absorbent material in said chambers, means for conveying air through one of said chambers, the room, and the other of said chambers, means f or periodically reversing the direction of ow of the air comprlsing means for alternately heating said chambers to cause the absorbent in the chamber heated to give' up moisture to the air therein.

2. Apparatus for conditioning the air in a room comprising two chambers, absorbent ma.- terial in said chambers, means for conveying air through one of said chambers, the room, and the otherof said chambers, means for periodically reversing the direction of i'low of the air comprising means for alternately heating said chambers to cause the absorbent in the chamber heated to give up moisture to the air therein and means for cooling the air entering the room by causing water t0 evaporate into the air.

3. Intermittent absorption refrigerating apparatus comprising a rst absorber-generator, a second absorber-generator, an evaporator, means for periodically causing an inert gas to ow first through the rst mentioned absorber-generator, the evaporator and the second mentioned absorber-generator and then through the second mentioned absorber-generator, the evaporator and the first mentioned absorber-generator comprising means for heating each of said absorbergenerators only when the inert gas is owing through it after having passed through the other absorber-generator and the evaporator.

4. The process of conditioning air Which consists in periodically passing the air over two separate bodies of absorbent material, first in one direction and then in thev other, maintaining the body over which the air first passes at a lower temperature than the other body thereby causing the body over which the airrst passes to remove moisture from the air and thereby causing ing means and so arranged that when one of said absorber-generators is subjected to the heat of the sun the other is shielded therefrom, and

having an opening in each of said absorber-gelierators near the end remote from said conveying meanasaid apparatus being characterized by the fact that during part of the day air flows in one of said openings, through one of said absorber-generators, through said conveying means and then through the other absorber-generator, and during another part of the day the air flows in the reverse direction, said reverse oW being caused by the reversal of said absorber-generators with respect to the sun, whereby air is dried as it passes through said shielded absorber-generator, and said heated absorber-generator is `reactivated for subsequent use as a drier.

6. Apparatus for conditioning air of the type employing two absorber-generators containing absorbent medium and one of which is periodically subjected to the heat of the sun to reactivate the absorbent while the other is shielded from the heat of the sun to permit water vapor to be absorbed from atmospheric air, and in which means is provided for delivering air discharged irom one absorber-generator to the other, said absorber-generators being characterized by the fact that each has an air inletso positioned that the heating of either one thereof will cause the air therein to rise and thereby cause air to flow first' through o ne absorber-generator, then through said air delivery means, and nally through the other absorber-generator.

7. Apparatus for conditioning air comprising a housing, independent absorber-generators con-l taining absorbent medium positioned at oppo-v site sides of said housing such that the sun may heat rst one and then the other thereof to drive off water vapor contained in said absorbent while one remains shielded from the heat of the sun to dry air passing therethrough, air inlet means to each of said absorber-generators, means within said housing for conducting air between said absorber-generators, and means operable to modify the condition of the air as it passes between said absorber-generators as the result of thermo-syphonic action caused by the heating of one of said absorber-generators by the sun.

8. The process of conditioning air which comprises passing a rising stream of air over absorbent medium heated by the sun to reduce the moisture content of the absorbent, conducting said flowing air stream into an area shielded from the heat of the sun, modifying the absolute humidity of the airV for a utilitarian purpose, then passing the air stream downwardly over absorbent medium shielded from the heat of the sun to dry the air, and periodically reversing the direction of air flow by subjecting said shielded absorber-generator to the heat of the sun.

9. The method of conditioning an enclosure which comprises passing' air overa rst body of absorbent to dry the air, cooling the air by evaporative cooling, conducting the cooled air to an enclosure, venting the air displaced by said cool air to the atmosphere after first conducting the same over partially saturated absorbent heated by the sun to reactivate said absorbent, and then reversingv the direction of air flow by heating the moistened absorbent by solar energy while shielding the rst body of absorbent therefrom.

10. Apparatus for conditioning air consisting of two chambers and an air conducting means connecting the chambers, each chamber containing a body of absorbent material, each chamber having an opening permitting communication between such chamber and a point outside the apparatus, vand each chamber having a heating arsaesa means; thel arrangement being such that when either chamber alone is heated air will pass in series through the other chamber, the air conducting means connecting the chambers, and

'finally through said chamber being heated.

ll. A structure comprising a building having a room to be conditioned, la, pair oi chambers communicating with said room and absorbent bodies in each of said obers; each chber having a conduit for affording counicatlon between the same and the atmosphere outside said structure and each 1|; i 1:.. being positioned on the building to be shaded thereby from the heat of the sun when the other chamber is exposed to the heat of the sun; the arrangement being such that vwhen one of the obers is heated by the'sun a circulation of will be promoted, in series, from the exterior of the building through the other chamber, said room and said chamber heated by the sun.

l2. Apparatus for drying air comprising two inter-connected chambers, each of which contains absorbent material, an opening near the top of each of said chambers to the atmosphere, means i3. Apparatus for remo moisture from vairv comprising a rst s. m containing absorbent material, a second cber containing absorbent material, means connecting said c 1- ers to the atmosphere and a conduit connecting said chambers whereby air lmay dow through said chambers and conduit in either direction, means for exposing the nrst mentioned chamber to a source of heat whereby the air is caused to ow from the rst mentioned chamber to the second mentioned chamber, means lfor exposing said second mentioned chamber to a source of heat after discontinuing the heating of the rst char whereby the air iscaused to iiow from the secon mentioned chamber' to the rst mentioned l1 ber, the 4arrangement being such 'that the absorbent material gives up moisture to the air whenthe chamber in which it is located is heated, and removes Amoisture from the air when the chamber in which it is located is not heated Vto be exposed to the heat of the sun in the afternoon, Vsaid chambers containing independent charges of absorbent material, and means for conveying air periodically in opposite directions n through iir'st one Volf said chambers, said room, and then through the other of said chambers.

15.-'I'he process of conditioning air which comp passing the air over two separate bodies oi absorbent material periodically, rst in one direction, and then in the opposite direction by alternately heating one of said/bodies above the temperature of the other, the process being such that the absorbent bodies are automatically caused to alternately give up moisture to the A air synchronously with the periodic ow of the air, the moisture so given up being moisture which has been absorbed from. the air by one of the bodies when that body was not being heated.

i6. The method of conditioning air which comprises drying one portion of a stream of air for a useful purpose by passing it over absorbent material shielded from the heat of the sun during the forenoon, which absorbent material has body of absorbent material, and then another body thereof, one of said bodies being subject to the heat of the sun and the other being shielded therefrom during part of the day, and the position of said bodies with respect to the sun being reversed during another part of the day, whereby the air passing over said shielded body of absorbent is dried for a' useful purpose, .and the other body of absorbent material being heated bythe sun is being simultaneously reactivated foruse later in drying other air.

18. Apparatus for conditioning air of the type employing two absorber-generators containing absorbent mediums and connected by iluid conveying means including a chamber to be lcondi`4 tioned for conducting air in series therethrough, said apparatus requiring only a source of heat to energize and operate the same and being constructed and arranged to condition atmospheric air at atmospheric pressure, and to automatically cause flow of the air being conditioned therethrough by thermo-syphonic action, said apparatus being characterized by the fact that when one absorber-generator is being heated 4by a source of heat the other is shielded therefrom,

19. Apparatus ior conditioning air of the type employing two absorber-generators containing independent absorbent charges and one of which is alternately subjected to the heat of the sun for a period of time to reactivate the absorbent while the other is shielded from the heat of the sun for a period of time to permit water vapor to be absorbed from atmospheric air, and thereafter said absorber-generators are reversed with respect to the heat of the sun, said vapparatus being characterized by the fact that the dried air delivered by oneL of said absorber-generators is conducted to a point of use which is heat insulated from both of said absorber-generators, the air being subsequently returned to the other absorber-generator for use in reactivating said` last named absorber-generator.

Images