US3775996A

US3775996A - Tiltable air-cooled absorption refrigeration apparatus of the inert gas type

Info

Publication number: US3775996A
Application number: US00235366A
Authority: US
Inventors: P Blomberg
Original assignee: Electrolux AB
Current assignee: Electrolux AB
Priority date: 1972-03-16
Filing date: 1972-03-16
Publication date: 1973-12-04
Anticipated expiration: 1990-12-04

Abstract

Absorption refrigeration apparatus of the inert gas type is disposed in a vertically extending plane when it is being operated to produce useful refrigeration. Vapor and liquid flow at the same time in parts of the apparatus formed of piping which, when the apparatus is upright, is inclined to the horizontal at an angle greater than 4* and within a range of 20*. By introducing liquid to a supply line at a sufficient height for gravity flow to the piping during operation of the apparatus liquid will always flow to the piping when the apparatus is tilted to either side from the vertical in the vertically extending plane through an angle not exceeding the angle at which the piping is inclined to the horizontal when the apparatus is upright.

Description

Dec. 4, 1973 United States Patent [1 1 Blomberg Anderson........,...Q.................

[ TILTABLE AIR-COOLED ABSORPTION REFRIGERATION APPARATUS OF THE ,INERT GAS TYPE Primary Examiner-William F. O'Dea Assistant Examiner-Peter D. Ferguson Attorney-Edmund A. Fenander [75] Inventor:

[57] ABSTRACT Absorption refrigeration apparatus of the inert gas Sweden [22] Filed: 1972 type is disposed in a vertically ext-ending plane when it is being operated to produce useful refrigeration. Vapor and liquid flow at the same time in parts of the 21 App]. No.: 235,366 I apparatus formed of piping which, when the apparatus is inclined to the horizontal at an angle and within a range of 20. By introducing liquid to a supply line at a sufficient height for gravity flow to the piping during operation of the apparatus liquid will always flow to the piping when the 4 .m h m m re pt m :68 30 3 9 %9 M5 6 1% a 8 0 54 w s I! 9 2 44 6 l 2 m 6 mmh" mmm l m C SM.. UIF 1]] 2 8 555 [rll[ References Cited UNITED STATES PATENTS apparatus is tilted to either side from the vertical in the vertically extending plane through an angle? not ex- 62/490 ceeding the angle at which the piping is inclined to the horizontal when the apparatus is upright. 62/491 X 62/490 X 3,134,245 5/1964 Phillips et a1. 3,137,147 6/1964 Boren et a].

' 1,960,821 5/1934 Maiuri et a1. 3,065,609 11/1962 1 Claim, 5' Drawing Figures TILTABIJE AI-CDOLEI) SORP'IION REFRIGERATION APPARATUS OF THE INERT GAS 'IYlPlE BACKGROUND OF THE INVENTION 1. Field of the Invention In air-cooled absorption refrigeration apparatus of the inert gas type refrigerant expelled from absorption solution in a generator flows to a condenser in which it is liquefied. Liquefied refrigerant is conducted from the condenser to an evaporator in which, due to evaporation and diffusion thereof into an inert gas, a refrigerating effect is produced. The evaporator forms a part of an inert gas circuit which includes an absorber in which refrigerant vapor is absorbed into absorption liquid. The refrigeration apparatus is disposed in a vertiw cally extending plane when it is being operated to produce useful refrigeration.

2. Description of the Prior Art In absorption refrigeration apparatus of the kind under consideration, such apparatus heretofore has been associated with a cabinet which must be supported in a horizontal position to make certain that the apparatus will operate correctly and produce useful refrigeration. Only small mounting errors have been permissible when installing refrigeration apparatus on a cabinet because of the absolute requirement that any inclination of the apparatus must be avoided at 1 all costs. This is so because of the tendency of the refrigeration apparatusto malfunction when it is tilted from the vertical to the slightest degree. I-Ieretofore, it has been a recognized rule that only a maximum deviation of 3 in either direction from the vertical can be tolerated. Within this range refrigeration apparatus of the inert gas type has functioned in a satisfactory manner.

Absorption refrigeration apparatus of the kind under consideration is operated by a source of heat, such as an electrical heating element or a fuel burner operated by liquid or gaseous fuel. It is usually the practice to employ a fuel burner when the refrigeration apparatus is provided on a boat or a travel trailer and a source of electrical supply is not available. But since the maxi-- mum deviation of refrigeration apparatus from the vertical that can be tolerated has not changed, this means that refrigeration apparatus provided on boats and travel trailers, which often are not substantially upright or erect, will malfunction and cease to produce useful refrigeration which is objectionable.

SUMMARY OF THE INVENTION It is an object of my invention to provide absorption refrigeration apparatus of the inert gas type which, when it is operating to produce useful refrigeration, can be inclined in either direction from the vertical through angles larger than heretofore possible.

Another object is to provide such tiltable apparatus capable of produding useful refrigeration when installed in boats subject to rolling and in mobile trailers which assume different angular positions when they are parked on sloping terrain and when being moved from place to place.

More particularly, it is an object to provide such absorption refrigeration apparatus which, when it is operating to produce useful refrigeration, can be tilted to each side from the vertical through an angle greater than 4 and in a range up to I accomplish this by providing my improvement in absorption refrigeration apparatus which is disposed in a vertically extending plane when it is being operated to produce usefulrefrigeration and in which vapor and liquid flow at the same time in parts thereof formed of piping. Further,

such piping, when the apparatus is upright, is inclined BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a side view, in section, of a refrigerator and an air-cooled absorption refrigeration system of the inert gas type associated therewith which embodies my invention;

FIG. 2 is a rear elevational view, partly broken away, of the refrigerator shown in FIG. 1;

FIG. 3 is a fragmentary view taken at line 3-3 of FIG. 2;

FIG. 4 is a diagrammatic representation to illustrate the true inclination to the horizontal of seen in FIG. 1; and

FIG. 5 is a fragmentary view of parts shown in FIG. 1 to illustrate a modification of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT.

Referring to FIGS. 1 and 2, I have shown my invention in connectionwith a refrigerator comprising a cabinet 10 having an inner liner I1 arranged to be supis afforded at a front opening adapted to be closed by an insulated door 16 hinged in any suitable manner (not shown) at the front of refrigerator cabinet I0.

The thermally insulated compartment 15 is arranged to be cooled by an evaporator 17 of absorption refrigeration apparatus of the inert gas type. Refrigeration apparatus of this type comprises a generator 18 con taining a refrigerant, such as ammonia, in solution in a body of absorption liquid, such :as water. As shown in FIGS. 2 and 3 heat is supplied to the generator 18 from a heating tube 19 which may be heated by an electrical heating element20, for example, which is disposed within the tube and connected by conductors ZI to a source of electrical supply. The heat supplied to the generator 18 and'absorption solution expels refrigerant vapor out of solution, and, in a manner to be described hereinafter, refrigerant vapor passes upward from the generator through a vapor supply line or conduit 22 into an air-cooled condenser 23" in which the vapor is liquefied by surrounding cool air which flows in physical contact therewith. The liquefied refrigerant flows from the condenser through a conduit 24 into the upper closed end of the evaporator 17 at 17a.

The evaporator 17 forms the upper straight part of an outer looped coil having a bend 25 and a lower straight partwhich forms the outer passageway of a gas heat exchanger 26, the upper and lower straight parts of the outer coil being in different vertical planes. An inner looped coil extends lengthwise within the outer looped coil and includes a bend 27a and upper and lower straight parts 27b and 270, the part 27b being disposed within the evaporator 17 and the part 27c forming the inner passageway of the gas heat exchanger 26.

.The liquefied refrigerant evaporates and difiuses into an inert pressure equalizing gas, such as hydrogen,

which flows upward through the inner looped coil and passes from the upper open end 27a thereof into the presence of the refrigerant. Due to evaporation of refrigerant into inert gas in the evaporator 17, a refrigerating effect is produced with consequent absorption of heat from the surroundings.

The rich gas mixture of refrigerant and inert gas formed in the evaporator 17, that is, the annular passageway between the upper straight parts of the outer and inner looped coils, .flows from the lower end thereof through the coil bends and the outer passageway of the gas heat exchanger 26, that is, the annular passageway between the lower straight parts of the outer and inner looped coils. The lower ends of the outer and inner looped coils respectively include

parts

26a and 27d which are transverse to the vertical plane of the gas heat exchanger 26 and form the lower part thereof.

. As best seen in FIG. 1, the rich gas, together with an unevaporated refrigerant, flows from the outer passageway of the gas heat exchanger 26 through a conduit 28 into an absorber comprising a vessel 29 and a looped coil 30. In the absorber vessel 29 and looped coil 30 refrigerant vapor is absorbed into liquid absorbent, such as water, which enters through a conduit 31. The hydrogen or inert gas, which is practically insoluble and weak in refrigerant, is returned -to the upper closed end of evaporator 17 from the upper end of the absorber coil 30 through the inner passageway 27d and 270 of the gas heat exchanger 26 and inner passageway 27b of the evaporator 17.

Absorption liquid enriched in refrigerant in the absorber flows from the vessel 29 through an outer passageway 32 of an elongated liquid heat exchanger 33 which, within the generator 18, includes an outer vertical pipe 34 and an inner vertical pipe 35. Rich absorption liquid flows from the passageway 32 through a horizontal conduit 36 into a vertical standpipe 37. The conduit 36 is connected to standpipe 37 at a point 38 which is at a level below the liquid surface level 39 of the column of liquid held in the pipe 37. As seen in FIG. 2, the liquid surface level 39 is at approximately the same level as the liquid surface level in the absorber vessel 29.

The extreme lower end of the pipe 37 is connected to the lower end of a pump pipe or vapor-liquid lift tube 40 heat conductively connected to the heating tube 19, as by welding, for example. Liquid is raised by vaporliquid lift action through the tube or pump pipe 40 into the upper part of the pipe 35. The absorption liquid from which refrigerant vapor has been expelled flows downward by gravity through the inner pipe 35, the latter extending through the liquid heat exchanger 33 and forming an inner passageway thereof. The pipe 35 is connected to the conduit 31 from which weak absorption liquid overflows into the upper end of absorber coil 30 at a point 30a which is below the liquid surface level 41 in pipe 35.

The generator 18, together with a part of the liquid heat exchanger 33, are embedded in a body of insulation 42 retained in a metal shell or casing 43 having an opening 44a in the bottom 44 thereof. The electrical heating element 20, with the conductors 21 connected thereto, is arranged to be positioned within the heating tube 19 through the opening 44a in any suitable manner (not shown).

In the operation of the refrigeration apparatus, vapor generated in the vapor-liquid lift pump 40 flows from the upper end thereof to a gas separation chamber 35a at the extreme upper end of the standpipe 35 and passes through openings 35b in the side wall thereof into the outer passage 45 formed between the inner and

outer pipes

35 and 34, respectively. The vapor in the passage 45 depresses the liquid level therein to a point 46 and flows through enriched absorption liquid in conduit 36 and pipe 37 by bubble action. After the generated vapor is analyzed in this manner in the conduit 36 and pipe 37, the refrigerant vapor passes from the upper part of the pipe 37 and vapor supply line 22 to the condenser 23, as previously explained.

In order to pre-cool liquid refrigerant before it flows into the presence of inert gas at the upper closed end of the evaporator 17, the conduit 24 is heat conductively connected to the gas heat exchanger 26 at 24a, 24b and 24c and heat conductively connected to the evaporator 17 at 24d. The condenser 23 is connected by a conduit 47 to a part of the gas circuit, as to the conduit 28, for example, so that any inert gas which may pass through the condenser 23 can flow to the gas circuit.

With the evaporator 17 positioned in the compartment 15 of the cabinet 10, the other components of the refrigeration apparatus are located in a vertically extending apparatus space 48at the rear of the cabinet which is defined by the rear portions 12a of the lateral side walls of the outer shell 12 which project beyond the rear insulated wall 49. The top of the outer shell 12 extends rearward to the forward part of the apparatus space 48. Natural draft is produced in the space 48 and causes upward circulation of ambient air due to heat radiated by absorber vessel 29 and coil 30 and by the condenser 23, so that surrounding cool air can flow directly over their surfaces and assure adequate cooling of these parts or components. The top and bottom of the space 48 are open to enable air to flow freely upward therein.

As best shown in FIGS. 1 and 2, the gas heat exchanger 26, which extends across the cabinet 10 between the lateral sides thereof, is disposed within a body of insulation 14a retained in a removable wall section 50 of the rear insulated wall 49 to facilitate the insertion of the evaporator 17 within the cabinet. The lower part of the gas heat exchanger 26, which is transverse thereto and formed by the lower ends 26a and 27d of the outer and inner looped coils, respectively, projects rearwardly from the body of insulation into the apparatus space 48. The removable wail section 50 closes an opening in the rear insulated wall 49 and is removably secured thereto in any suitable manner (not shown).

In order that the refrigeration apparatus can be tilted from an upright position at angles substantially larger than heretofore without impairing its ability to produce useful refrigeration, the condenser 23 comprises a pair of

hollow members

51 and 52 which slope upward and are united at 53 at their lower ends and form an angle therebetween. The

hollow members

51 and 52 have an inlet for refrigerant at one level at 54 at the region the vapor supply line 22 is connected to the condenser 23.

Further, the

hollow members

51 and 52 have an outlet for liquefied refrigerant at a lower level at the region 53 erantoutlet 53 for conducting-liquid refrigerant from the condenser 23 to the evaporator 17 at the point 17a. Refrigeration apparatus like that shown in FIGS. 1

and 2 and just described has been constructed and operated to produce useful refrigeration'in whichthe

hollow members

51 and 52 are inclined upward from the horizontal at angles greater than and up to whereby the apparatus can be operated when it is tilted to each side from the vertical through an angle in a range of at least 15. When the apparatus is tilted in this manner in the vertical plane of the

hollow members

51 and 52 in either direction from the vertical, the condenser continues to function in a normal manner and the passageway for vapor in the

hollow members

51 and 52 will not be obstructed or blocked by liquid.

In absorption refrigeration apparatus of the inert gas type provided heretofore, it has only been possible to incline the apparatus about 3 from the vertical, as

- pointed out above, without impairing the ability of the is too low for the reason that this vertical height determines the vertical location of the evaporator which, be-

cause of its position in the cabinet interior, must be as close as possible. to the ceiling of the space being cooled.

As seen in FIG. 2 and described above, the condenser 23 comprises a relatively long length of piping and yet is inclined at a large angle to the horizontal. This is accomplished by dividing the condenser 23 into two

parts

51 and 52, each of which has a large angle of inclination. As pointed out above, refrigeration apparatus like that shown and described has been constructed and operated to produce useful refrigeration in which the

hollow members

51 and 52 are inclined upward from the horizontal at angles greater than 15. With such inclination of the members Si and 52 the apparatus can be operatecl when it is tilted to each side from the vertical through an angle in a range of at least 15. Stated another way, the apparatus, when being operated to produce useful refrigeradon, is tiltable through a predetermined angle to each side from a vertical plane passing through the refrigerant outlet 53 which is dependent upon the angle the

hollow members

51 and 52 are in-' clined and slope upward from the horizontal when the apparatus is upright. Further, the refrigerant supply conduit 24 includes at least one part 24d which, when the apparatus is upright, slopes upward from the horizontal through an angle greater than the predetermined angle.

The condenser 23 illustrated in FIGS. 1 and 2 and described above is disclosed and claimed in copending P. E. Blomberg and K. G. Boreti application SerQNo. 235,367 filed Mar. 16, 1972.

In order to make certain that the vapor-liquid lift pipe or pump 40 will function properly when the refrigeration apparatus is tilted through relatively large angles from the vertical in the manner contemplated by my invention, the absorber vessel 29 is located as close as possible to the generator shell 43 and bottom 44 thereof. By doing this large changes in the level of the liquid body in the absorber vessel 29 and "the height of the liquid column in the pump pipe 40 are avoided when the refrigeration apparatus is tilted'through the largest permissible angle.. Further, the absorber coil 30 and. generator18 are located as near as possible to one another so that the distance between the liquid level 41 in the conduit 35 and overflow point 30a of conduit 31 will be relatively small. This will insure flow of weak absorption liquid into the upper end of the absorber coil 31 even when the apparatus is tilted through the largest permissible angle. 7

- When the refrigeration apparatus is started weak absorption liquid may be present in the conduit 24 through which liquefied refrigerantis supplied to the evaporator 17 from the condenser 23. In order for the condensed refrigerant to displace weak absorption liquid in the conduit 24 the heights of the two legs of the conduit 24 extending downward from the outlet 53 of the condenser. 23 and downward from the liquid overflow point 17a at the evaporator 17 desirably must be related to one another in a particular manner. The leg of the conduit 24 extending'downward from the condenser. region 53 to the lowest part 24b thereof may be referred to as the first leg of the conduit 2d which in a broadsense is U-shaped and forms a liquid trap. The leg of the conduit extending downward from the evaporator region. 17a to the lowest part 24b thereof may be referred to as the second leg of the conduit 24.

The two legs of the U-shaped conduit M are of such length that the ratio of the lengths of the first leg to the second leg is about 1.5 to 1.0. The refrigeration apparatus is constructed so that this ratio will be maintained even when the apparatus is tilted through the largest permissible angle.

In FlG. 2 the evaporator 17 is illustrated as a straight conduit or pipe length having a relatively large inclination to the horizontal. InFlG. 1 it will be seen that the evaporator 17 is adjacent to the rear-wall 49 of the cab inet l0 and parallel thereto. As seen in FIG. 2, the hollow members SI'and 52 substantially bridge the apps.- ratus space 48 at the rear of the cabinet 10 between the lateral sides thereof.

In order for the other components of the refrigeration apparatus to function properlyit is necessary that conduits in which liquid normally is present are not suddenly depleted of liquid or that the heights of the liquid columns change sufficiently so that the normal manner in which the apparatus functions is completely changed.

In accordance with my invention the flow of vapor is not obstructed or blocked by liquid in conduits in which liquid and vapor flow at the same time. As explained above, liquid and vapor flow at the same time in parts of the inert gas circuit including the evaporator 17, gas heat exchanger 26 and absorber 30 which comprise conduits or looped coils formed of piping. In

order to prevent liquid from blocking the flow of vapor the piping of the aforementioned parts, when the apparatus is upright, is inclined to the horizontal at an angle which is greater than 4 and within a range up to Liquid refrigerant is supplied to the evaporator 17 through conduit 24 having an inlet at 53 receiving liquid at one level and an outlet at 17a at a lower level from which liquid flows into the evaporator 17. Absorption. liquid is supplied to the absorber coil through conduit means 35, 31 having an inlet receiving liquid at one level at the vicinity of the openings 35a at the upper end of conduit 35 and an outlet'at a lower level at30a from which liquid flows from conduit 31 into the absorber coil 30.

Each of the inlets for the conduit 24 and conduit means 35, 31 is at such a height above its associated outlet at 17a and 30a, respectively, that liquid will flow through the conduit 24 and conduit means 35, 31 when the. apparatus is being operated and tilted to either side from the vertical through an angle not exceeding the angle at which the evaporator and absorber piping is inclined to the horizontal when the apparatus is upright.'Further, the evaporator, gas heat exchanger and absorber piping is inclined to the horizontal at angles corresponding to the angles at which the

hollow members

51 and 52 of the condenser 23 are inclined to the horizontal.

As seen in FIG. 2 the evaporator 17, gas heat exchanger 26 and straight parts 30b of the absorber coil 30, which are parallel to the vertically extending plane in which the apparatus is disposed, are inclined to the horizontal at a first angle.

The top straight part 30b of the absorber coil 30, for example, is inclined to the horizontal at an angle of about 10, as indicated in FIG. 1. The evaporator 17, gas-heat exchanger 26 and other straight parts of the absorber coilare inclined to the horizontal at about the same angle as the top straight part 30b of the absorber coil.

The bend 25 between the evaporator 17 and gas heat exchanger 26 and the bends 56 connecting the straight parts 30b of the absorber coil 30 also are inclined to the horizontal at about the same angle as the evaporator 17, gas heat exchanger 26 and straight parts of the absorber coil 30. While the inclination of the bends 56 to the horizontal appears to be about 13, as seen in FIG. 1, this is not the true inclination of the bends 56 to the horizontal which actually is less and about 10.

This can best be explained by referring to FIG. 4 in which 1 represents the length of the bends 56 as they appear in FIG. 1 which are at a false angle of inclination a. When the path of flow of the fluids in the bends 56 is taken into consideration, as shown in the bottom part of FIG. 4, it will be observed that the actual length of the bends 56 is l X rr/2.

If in FIG. 4 the designation for the lower end of the bends 56 is now moved from point x (for the false inclination in FIG. 1) to the point y (for the true inclination in FIG. 4), the true angle of inclination B is obtained which is less than the false angle a and about 10, the same angle of inclination to the horizontal as the long straight parts 30b of the absorber coil 30.

However, the bend 25 between the evaporator 17 and gas heat exchanger 26 and the bends 56 connecting the straight parts 30b of the absorber coil 30, may be inclined to the horizontal at a second angle which is larger than the first angle. This is shown in FIG. 5 in which the bends 56 connecting the long straight portions 30b of the coil 30 are inclined to the horizontal at an acute angle which is much greater than the angle of inclination of the bends 56 in FIG. 1. While the angle of inclination of the bends 56 in FIG. 5 are false and not true, as explained above, the inclination of the bends 56 to the horizontal is such that their true inclination is greater than the inclination to the horizontal of the long straight parts 30b of the absorber coil 30'.

In this way the overall height of the apparatus will be reduced, when necessary, and require less vertical space in the cabinet with which it is associated.

It has been found that boats, particularly boats of large size, have inclinations in the fore-aft direction of about 3. Further, it seldom occurs that such fore-aft inclinations exceed 5. Hence, refrigeration apparatus of the kind heretofore provided cannot be employed on boats. However, absorption refrigeration apparatus embodying my invention can be employed on boats with fore-aft inclinations in the range indicated above.

There are many types of boats having different characteristics with respect to the manner in which they move angularly from the vertical. While large boats seldom move angularly from the vertical to any great extent, as pointed out above, sailing vessels and the like from time to time are subjected to considerable rolling and angular movement from the vertical. Hence, in refrigeration apparatus intended for use on sailing vessels the evaporator and absorber piping of necessity must be inclined to the horizontal at relatively large angles; and in refrigeration apparatus intended for use on large size boats the evaporator and absorber piping can be inclined to the horizontal at smaller angles.

I claim:

1. Absorption refrigeration apparatus comprising a. a generator, a condenser, an evaporator, an absorber and members connecting the aforesaid parts to form a complete system for circulation of a refrigerant, an absorption liquid and an inert gas,

b. the inert gas circulating in an inert gas circuit including said evaporator and said absorber, liquid refrigerant and refrigerant vapor flowing at the same time in said evaporator and absorption liquid and refrigerant vapor flowing at the same time in said absorber,

c. said apparatus being disposed in a vertically extending plane when being operated to produce useful refrigeration,

d. the aforesaid parts in which vapor and liquid flow at the same time including piping which, when said apparatus is upright, is inclined to the horizontal at an angle greater than 4,

. the circuit for circulating refrigerant including first circuit means for supplying liquid refrigerant to said evaporator, said first conduit means having an inlet receivingliquid refrigerant at one level andan outlet at a lower level from which liquid flows into said evaporator,

f. the circuit for circulating absorption liquid including second conduit means for supplying absorption liquid to said absorber, said second conduit means having an inlet receiving liquid at one level and an outlet at a lower level from which liquid flows into said absorber, and

g. each of the inlets for the first and second conduit means being at such a height above its associated outlet that liquid will flow through said first and 3,775,996 9 I 10 second ebnduit means when said apparatus is being clined to the horizontal when said apparatus is upoperated and tilted to either side from the vertical ri ht in said vertically extending plane through an angle not exceeding the angle at which said piping is inn s

Claims

1. Absorption refrigeration apparatus comprising a. a generator, a condenser, an evaporator, an absorber and members connecting the aforesaid parts to form a complete system for circulation of a refrigerant, an absorption liquid and an inert gas, b. the inert gas circulating in an inert gas circuit including said evaporator and said absorber, liquid refrigerant and refrigerant vapor flowing at the same time in said evaporatoR and absorption liquid and refrigerant vapor flowing at the same time in said absorber, c. said apparatus being disposed in a vertically extending plane when being operated to produce useful refrigeration, d. the aforesaid parts in which vapor and liquid flow at the same time including piping which, when said apparatus is upright, is inclined to the horizontal at an angle greater than 4*, e. the circuit for circulating refrigerant including first circuit means for supplying liquid refrigerant to said evaporator, said first conduit means having an inlet receiving liquid refrigerant at one level and an outlet at a lower level from which liquid flows into said evaporator, f. the circuit for circulating absorption liquid including second conduit means for supplying absorption liquid to said absorber, said second conduit means having an inlet receiving liquid at one level and an outlet at a lower level from which liquid flows into said absorber, and g. each of the inlets for the first and second conduit means being at such a height above its associated outlet that liquid will flow through said first and second conduit means when said apparatus is being operated and tilted to either side from the vertical in said vertically extending plane through an angle not exceeding the angle at which said piping is inclined to the horizontal when said apparatus is upright.

2. Apparatus as set forth in claim 1 in which said piping of said parts in which vapor and liquid flow at the same time, when said apparatus is upright, is inclined to the horizontal at an angle greater than 5*.

3. Apparatus as set forth in claim 1 in which said piping of said parts in which vapor and liquid flow at the same time, when said apparatus is upright, is inclined to the horizontal at an angle greater than 4* and within a range of 20*.

4. Apparatus as set forth in claim 1 in which all of said piping of said parts in which vapor and liquid flow at the same time, when said apparatus is upright, is inclined to the horizontal at the same angle.

5. Apparatus as set forth in claim 1 in which said piping of said parts in which vapor and liquid flow at the same time includes first parts parallel to said vertically extending plane in which said apparatus is disposed and second parts transverse thereto, the first parts of said piping, when said apparatus is upright, being inclined to the horizontal at an angle greater than 4*, and the second parts of said piping, when said apparatus is upright, being inclined to the horizontal at an angle greater than the angle at which the first parts are inclined to the horizontal.