US2088276A

US2088276A - System for the conversion of heat

Info

Publication number: US2088276A
Application number: US645484A
Authority: US
Inventors: Nesselmann Kurt; Altenkirch Edmund
Original assignee: Siemens AG
Current assignee: Siemens Schuckertwerke AG; Siemens AG
Priority date: 1931-12-08
Filing date: 1932-12-02
Publication date: 1937-07-27
Anticipated expiration: 1954-07-27
Also published as: FR747191A

Description

July 27, 1957- K. NESSELMANN ET AL SYSTEM FOR THE CONVERSION OF HEAT Filed Dec. 2, 1932 9 Sheets-Sheet 1 i W V W y 3 K. NESSELMANN ETAL 2,088,276

I SYSTEM FOR THE CONVERSION OF HEAT Filed Dec. 2, 1932 1y21,1931-- K. NESSEL'MAN Em 2 088 276 SYSTEM FOR THE CONVERSION OF HEAT Filed Dec. 2, 1932 9 Sheets-Shept 3 y 1937' K. NESSELMANN ET AL ,088,276

SYSTEM FOR THE CONVERSION OF HEAT 9 Sheets-Sheet 4 Filed Dec. 2, 1932 y I K. NESSELMANN ET AL 2,088,276

SYSTEM FOR THE CONVERSION OF HEAT filled-Dec. 2, 1952 9 Sheets-Sheet s did July 27, 1937. I K. NESSELMANN ET m. 2,088,276

- SYSTEM FOR THE CONVERSION OF HEAT 9 Shegjsl-Sheeb 6 Filed Dec; 2, 1932' July 1937. K. N ESSELM ANN ET AL SYSTEM FOR THE CONVERSION 0515mm- 9 Sheets-Sheet 7 Filed Dec. 2, 1952 Jul); 7, 1937- K. NESSELMANN ET AL 2,088,276

SYSTEM FOR THE CONVERSION OF HEAT Filed Dec. 2, 1952' 9 Sheets-Shet a J y ,1 K. NESSELMAN'N ET AL ,088,276

SYSTEM FOR THE CONVERSIONOF HEAT Filed necfz, 1932 9 Sheets-Sheet e Patented July 27, 1937 SYSTEM FOR- THE CONVERSION OF I IEAT Kurt Nes'selmann, Berlin-Siemcnsstadt, and Edmund Altenkirch, Neuenhagen, near Berlin,

Germany, assignors to ,Siemens- Schuckertwerke Aktiengesellschaft, Bcrlin-Siemensstadt, Germany,- a corporation of Germany Application December 2, 1932, Serial No. 645,484 In Germany December-8,- 1931 H 15 Claims. Our invention relates to a system for the conversion of heat in which one or more absorption apparatus of the intermittent .type are employed in a special manner for increasing the-efliciency of systems operating with heat converters.

As it is well known in the art all refrigerating apparatus of the absorption type contain parts which take up and some which give up heat. In absorption refrigerating apparatus of the intermlttent type the generator (or absorber-generator) takes up heat during the generating period, whereas the condenser (or condenser-evaporator) gives up heat. On the other hand, during .the absorption period the evaporator (or condenser-evaporator) takes up heat, whereas the absorber (or absorber-generator)- gives up heat. That is to say in each two'successive periods, generating and absorption period, a conversion of heat takes place, i. e., a conversion of heat of a given temperature to heat of another temperature during which heat is taken up twice and given up twice.

Heat converters according to the invention are absorption refrigerating apparatus of the intermittent or continuous type, steam power'plants, steam accumulators, in general all such systems in which heat of a given temperature is converted to heat of another temperature or into another form of energy. with this object in view accord- 30 ing to the invention a system for the conversion of heat is provided in which absorption refrigerating apparatus of the intermittent type are asso ciated with one another or with other heat con- 'verters to form a system so that parts of the apparatus are in heat exchange with one another in such a manner that on the. one hand an exchange takes place between heat-which in one part of an intermittently operating absorption apparatus is liberated by condensation or absorp- 40 tion or is taken up as heat of generation or evaporationand onthe other hand the heat which is simultaneously taken up in one part of one of the. other heat converters as heat of'generation or evaporation and liberated as heat of 45 condensation or absorption. The system is preferably carried out in such a way as not to cause a heat exchange in the above-described manner between the parts of one'and the same absorption apparatus of the intermittent type. The main feature of such systems is to convert heat in all cases by avoiding as far as possible irreversible cycles.

Q g The accompanying drawings forming part of this application illustrate several embodiments of 55 .our invention.

In the drawings:

Fig. 1 shows diagrammatically a system in which two refrigerating apparatus of the absorp-' tion intermittent type are in heat exchange relation with each other for the production of re? 5 frigeration;

Fig. 2 shows diagrammatically a. modification of the invention in which three apparatus of the absorption intermittent type are in heat exchange for the production of live steam by waste heat;

Fig. 3 shows diagrammatically another modification in which two absorption refrigerating apparatus of the intermittent type are in heat exchange relation with eachother both during the generating and absorption period for the production of refrigeration;

Fig. 4 shows diagrammatically a further modiflcation of the invention in which an absorption apparatus of the intermittent type as heat accumulatoris in heat exchange with a steam generating plant;

Fig. 5 shows a diagrammatic view of another modified form of the invention in which an absorption apparatus of the intermittent type is used as a cold accumulator;

Fig. 6 shows diagrammatically a thermal power plant operating with four absorption refrigerating apparatus of the intermittent type;

Fig. 'Iillustratesin diagrammatic form another embodiment of the invention in which a continuously operating absorption refrigerating apparatus with an absorption apparatus of the V intermittent type for the production of heat and refrigeration are combined;

Fig.- 8 shows diag ammatically another modiflcation of theinvention in which an absorption apparatus of'the intermittent type is in heat exchange with a continuous absorption apparatus for the production of refrigeration of a particularly low temperature;

'Fig. 9 shows diagrammatically a system in which a continuously operating absorption refrigerating apparatus is in heat exchange with an absorption apparatus of the intermittent type serving as heat accumulator and Fig. 10 shows diagrammatically another embodiment of the inventionin which an inter-- mittently operating absorption apparatus is in heat exchange relation with a continuous absorption apparatus. llnthe first three embodiments of our invention two or more absorption apparatus of the intermittent type in heat exchan e relation with one another. Ina system ,i'or the convergiven up or taken up by one part of an intermittently operating absorption apparatus is supplied to or abstracted from a heat absorbing or heat radiating part of another refrigerant apparatus of the intermittent type.

In such a system, it is possible to utilize predetermined temperature ranges by approaching as far as possible the reversible cycle of conversion for the production of heat and refrigeration without being limited in this case with respect to the temperature at which the heat or cold is to be produced, as is, for instance, the case when employing absorption apparatus not in heat exchange relation with one another as a heat converter. The apparatus may be arranged in heat exchange with one another in various manners, depending upon the object in view. Absorption refrigerating apparatus of the intermittent type are so associated with one another that a heat exchange takes place, when the apparatus are working simultaneously in the same operating period or when they are working in different operating periods. The absorption apparatus may be so associated with one another that they are in heat exchange relation only during the generating period. In this case a high heating temperature may be utilized-for producing a greater amount of refrigeration. It is also possible to associate the apparatus with one another. for an exchange of heat during the absorption period. 7

This is particularly the case when heat of low temperature is to be used for the production of heat of higher temperature. Fina1ly,a heat exchange between apparatus is also possible during the generating period as well as during the absorption period. This case may be applied to advantage when producing refrigeration of a very low temperature ,by utilizing a high heating temperature.

By arranging more or less apparatus in a' suitable manner in heat exchange with one another it is thus possible to cover the corresponding temperature ranges in a most efficient manner depending upon the object in view.

If a predetermined maximum temperature range should be subdivided to cover a number of narrow temperature ranges, an even number (at least 6) of absorption apparatus of the intermittent type are required. This may be effected by arranging the absorption apparatus of the intermittent type in such a manner that during the generating period another number of absorption apparatus or apparatus groups are in heat exchange With one another than during the absorption period.

Incarrying out the invention as shown in Fig. 1, we provided two refrigerating apparatus of the absorption intermittent type which are connected in series during their common generating period and in parallel during the absorption period. This implies that a heat exchange between the apparatus takes place during the generating period and not during the absorption period. In this embodiment absorption apparatusare employed operating with solid absorbents or adsorbents.

In Fig. 1, l denotes the absorber-generator of the first apparatus. It consists of an enclosure 2, an inner tube 3 and back and front bottom plates 4 and 5. These parts are welded together to form a gas-tight container. Within the whole of the generator, heat conducting cross-ribs 6 are disposed which on the one hand serve to transfer the heat as uniformly as possible to the solid absorbent contained in the absorber-gento the air-cooled outer walls of the absorbergenerator. In the front bottom plate 5 a charging passage 1 is arranged through which the absorbing material, for instance, calcium chlorid or strontium bromide, is introduced into the generator. In the heat conducting cross-ribs 6 are formed openings 8 through which the refrigerant passes. Within tht inner tube 3 of the generator i an electric heating element 9 is disposed which is connected to the supply circuit consisting of the conductors II and I2 through a contact making clock I. By the contact making clock the heating element 9 is energized for a predetermined space of time and deenergized for another predetermined space of time.

During the generating period the gaseous refrigerant passes from the absorber-generator I through a conduit l3 into a container which serves as a condenser ll, whence the liquid refrigerant flows through a conduit I5 into an intermediate reservoir l6 surrounded by the insulation of the cooling chamber 24 of the refrigerator, an evaporator coil l1 being connected to the container Hi. The condenser H of the first absorption apparatus is designed in the form of an inner heating tube of the absorber-generator I8 of a second absorption refrigerating apparatus. This absorber-generator is designed in a manner similar to the absorber-generator l. The heat of condensation of the first absorption apparatus is utilized to heat the absorber-generator I8 so that during the condensation in the first absorption apparatus, the refrigerant is expelled from the absorber-generator I8. The vapor refrigerant passes through a conduit l9 into an aircooled condenser 20, from which the ,liquid refrigerant flows into an intermediate reservoir 2! likewise surrounded by the insulation of the cooling chamber 24 of the refrigerator in the same manner as the reservoir I6, the reservoir 2| being associated with the corresponding evaporator coil 22. Both evaporator coils are located in' a cold storage tank 23 projecting into the cooling chamber 24. 25 denotes an ice container for freezing ice cubes.

At the beginning of the absorption period the heating element 9 of the absorber-generator I is deenergized by means of the contact making clock [0. The temperature of both generatorabsorbers l and I 8 drops under the influence of the cooling air which comes into contact with the outer walls of the generator so that the pressure in both absorption apparatus is lowered, thus initiating the evaporation in the evaporator coils l1 and 22 for the refrigeration. The refrigerant of both absorption apparatus now returns in opposite direction to.the corresponding absorbergenerators where it is reabsorbed by the absorbent contained therein.

It is preferable to employ different absorbents with suitable refrigerants in both absorption apparatus. For instance as absorbent magnesium chloride and as refrigerant ethylamine might be employed for the first absorption apparatus, whereas in the second apparatus calcium chloride as absorbent and as refrigerant ammonia.

The advantage of this system in which the absorptionapparatus are in heat exchange with each other lies in the fact that by arranging both absorption apparatus in series during the generating' period a higher generating temperature tus to be heated. In this case the heat has todrop from the higher temperature level to the lower temperature level in an irreversible manner. Applying an absorption apparatus of the intermittenttype according to the invention theirreversibility of the process is avoided.

To produce live steam by waste heat, three ap-'v paratus of the absorption intermittent type as disclosed in Fig. 2 operate in parallel during their common generating period and in series during the absoption period. In this case absorption'apparatus are employed which operate with liquid absorbents. The absorber-generators of the absorption apparatus are designated by the numerals III, I2I and I3I. The apparatus are heated by waste steam during the generating period. The waste steam is supplied from a supply-conduit IIlI to the individual heating bodies II II, I20 and I30 cooperating with the respective absorberg"enerators through parallel connected branch conduits provided with corresponding'valves 1, I21; and- I31. The discharge conduits for the condensate enter a conduit I02. As a result of the heating the operating. medium contained in the absorber-generator is expelled from the solution. The vaporous operating medium passes through corresponding conduits H3, I23 and I33 into the respective condenser-evaporators II4, I24, and I34 which are cooled during this interval by the water'fiowing through the coolers IIG, I26 and I36. The conduit I03 serves to supply cooling water to the coolers, the supply being controlled by the corresponding valves II9, I29 and I39. The individual discharge conduits for the cooling water enter a common return conduit I04. By this cooling, the operating medium is condensed in the condenser-evaporators and the liquid operatingmedium is collected as shown inFig.2.

The evaporation of the operating medium expelled in the condenser-evaporators II4, I24, and I34 is eflected in this embodiment by shutting on after the generating period the heat applied to the absorber-generators with theaid of the valves Iil, I21 and I31 and by interrupting the supply of the cooling water to the coolers IIo,

I26 and I35 by means of the valves II9, I29 and I39. At the same time, devices for the transfer of heat are put into operation which transfer the heat required for the evaporation to the condenser-evaporators. II4 has at its lower portion a heating body 5 and the latter is supplied with waste'steam by opening the valve II8 which was closed during the generatingperiod. As a result of the application of heat, the operating medium evaporates in the condenser-evaporator H4 and again returnsto the weak solution in the absorber-gem.

erator III through a conduit H2. The vaporous.

operating medium is introduced below thelo west liquid level in the absorber-generator III with the aid of a perforated gas conduit I. The heat developing during the absorption period is uti-'- lized to heat thecondenser-evaporator I24. vTo

this'end, a closed system for the transfer of heat is available consisting of an evaporator III arranged in" the lower part of the absorber-generator III and of the condenser I43 associated therewith and disposed in the lower part0! the 0011- The condenser-evaporator one another.

In the embodiment shown denser evaporator I24. In the conduit connecting the evaporator I and the condenser I43 a valve I42 is provided. In this system I4I, I42, and I43 for the transfer of heat, an auxiliary medium is employed in a well-known manner which evap-. orates' in theevaporator HI and condenses in sequently, the operating medium also evaporates in the condenser-evaporator I34 and returns to the absorber-generator I3I through the conduit I32. ,A system I6I, I52 and IE3 serves to transfer the heat of absorption from the absorbergenerator I3I to a steam'boiler I64 employed for producing live steam. The condenser I63 of the system for the transfer of heat is arranged in the lower part of said steam boiler. The steam leaves the steam boiler through the conduit provided with the valve I68. I69 is a water supply conduit for the steam boiler and I10 a drain conduit. To the top of the condenser-evaporators II4, I24, and I34 conduits I44, I45, and I46 provided respectively with stop valves are connected through which the apparatus are charged with the absorption solution. In order that the solvent entrained during the operation from the absorber-generator into" the condenser-evaporator may flow back, drain conduits I41, I48 and I49 are employed, the latter being provided with valves I54, I and I56 which are opened from time to time by the attendant.

The controlof the valves which serve for the reversal of the periods may be effected by hand by the attendant, the valves being preferably so arranged as to be controlled by a common control member. In this manner, it is possible to carry out simultaneously all reversals by means of a single handle. It is also possible to provide in the case of large systems an electric control system for the reversal of the valves. All absorber-generators and condenser-evaporators as well as the steam boiler are prdvided in this embodiment with heat insulation.

By the arrangement 'shown in Fig. 2 a COIISid-r erably greater difference between the heating temperature attained and the waste heat temperature is obtained with a relatively small difference between the waste heat temperature and the cooling water temperature than with absorption apparatus not in heat exchange 'with in Fig. 3 in which refrigeration is produced in the cooling chamber of the refrigerator, the numeral I1I denotes the absorber-generator of the first absorption apparanged above the refrigerator through a conduit I'll. This condenser-evaporator is in direct heat-exchange relation with the absorber-genera.- tor I" of the second absorption apparatus. since the absorber-generator III is located within the condenser-evaporator I12 as disclosed in Fig. 3.

The heat of condensation of the first absorption apparatus is consequently transferred in this case directly through the walls of the absorber-generator I16 to the solid absorbent contained in the second absorber-generator so that here the refrigerant is also driven off. The latter passes through a conduit I11 into an air-cooled condenser I18. The liquid refrigerant of the second apparatus then flows into an intermediate reservoir I19, surrounded by the insulation of the refrigerator. To the bottom of the intermediate container I19 an evaporator coil I80 is connected in the usual manner. The evaporator coil I80 is arranged in a cold storage tank projecting into .the cooling chamber I8I. At the end of the generating period, the heating element I15 is deenergized, thereby puttingv into operation a system for cooling the absorber-generator I1 I. This cooling system consists of a cooling jacket I83 surrounding the' absorber-generator I1I. From the upper part of the cooling jacket I83 a conduit I84 leads to a cooler I86 which radiates heat to the surrounding air. A conduit I81 extends from this cooler to the lower part of the cooling jacket I83. An expansion vessel I85 is connected to the rising conduit I80. This cooling system is filled with a liquid to the level as shown in the expansion vessel I85. The circulation of liquid is controlled by means of a valve I88 which is adjusted by an electromagnet I89. The heating element I15 and the electromagnet I89 are connected to the supply circuit I9I, I92 through a contact making clock I90. The latter controls the system in such a manner that the valve is closed during the generating period and open during the absorption period.

As a result of the cooling duringthe absorption period the solid absorbent in the absorbergenerator IN is capable of reabsorbing the refrigerant. The latter evaporates now in the condenser-evaporator I12 and returns to the absorber-generator I1I through'the conduit I13. The heat of absorption is abstracted from the solid absorbent contained in the absorber-generator I16 by evaporating the refrigerant in the condenser-evaporator I12. Consequently, the refrigerant also evaporates now in the evaporator I80 and returns to the absorber-generator I16. The heat of evaporation necessary for this purpose is abstracted in a well-known manner from the cooling chamber I8I, thereby attaining the desired cooling effect. The absorber-generator III and the condenser-evaporator I12 are provided with heat insulation. By the system described in this embodiment it is possible to produce refrigeration at a very low temperature that could not be attained with absorption apparatus notin heat exchange with one another. Since further a high generating temperature may be employed similar to the first embodiment, the ratio of refrigeration produced to the heat applied, both expressed in calories, is favorable in spite of the low temperature of refrigeration.

In the above-described three embodiments the operating medium is driven off by applying heat energy to absorber-generators. Under circumstances, it is also advantageous for the reversible utilization of a certain amount of cold at a low temperature to effect the generation of the operating medium not by the heat given oil by a heating device located in the absorber-generator but by the use of a source of cold; for instance by the use of carbon dioxide snow. In this case the operating medium is expelled by carrying off the heat'of condensation at a temperature which ,lies lower than the temperature at which the condensate evaporates during the absorption period.

By combining heat converters with refrigerating apparatus of the absorption intermittent type, the latter may be employed in a special manner as heat and cold accumulators. A convenient application of the inventive idea may be, for instance, realized by combining an intermittently operating absorption apparatus with another heat converter so that the absorption apparatus is capable of giving up heat, absorbed and stored by the absorption apparatus during the generating period, to the heat converter during theabsorption period.

Fig. 4 illustrates an absorption apparatus of the intermittent type operating with a liquid absorbent and in heat exchange with a steam producing plant, the apparatus of the intermittent type being employed as a heat accumulator.

20I denotes a heat accumulator filled, for instance, with alkali liquor and insulated against the outside atmosphere. 202 is also a heat-insulated collecting vessel for condensed water vapor. This vessel is provided with a steam dome, to which a steam outlet conduit 208 is connected, the conduit being provided with a shutoff valve 209. The collecting vessel 202 forms a part of a liquidcirculating system consisting of a back and forth bent conduit 203 placed in the accumulator MI and of a diifusor 205. In the difi'usor 205, a nozzle is disposed which forms one end of a conduit 206 leading from a source of steam (not shown), the conduit 206 being provided with a valve 201. The circulating system consisting of the collecting vessel 202, the conduit 203 and the conduits 204 and 2I4 is at first filled with water to the level as shown in the vessel 202. On opening the valve 201 steam is blown into the diffusor 205, and then condensed in the condenser 203. The condensate fills up gradually the collecting vessel 202. In this case the heat of condensation is transferred to the alkali liquor contained in the container 20I, thus causing water to evaporate from the alkali solution. The water vapor passes into a vessel 2 employed as condenser-evaporator through a conduit 2I2 connected at the upper part to the vessel 20I. The vessel 2 is surrounded by a circulation jacket 2I5 provided with an insulating covering, an inlet conduit 2I6 for the cooling water being connected to the lowest for some distance beneath the ground water level 2I0 and is connected to a pump 2i! which serves to force the ground water to the jacket 2I5. The water after having cooled the condenser-evaporator 2H and escaped from the upper part of thejacket 2I5 is carried off by the conduit 2I8. In this manner the water vapor driven off from the alkali solution is condensed in the vessel 2II.

In order to discharge the heat accumulator 20I valve 201 is to be closed and valve 209 to be opened. The water vapor leaving the accumulator will cause a drop of pressure in the accumulating

system

202, 204, 203 and, therefore, a drop in temperature takes place. After a short time the temperature of the water contained in pipe 203 becomes lower than the temperature of the solution in the absorber 20I. that the heat flows-from the alkali solution 20I to the water contained in pipe 203. As a consequence, the alkali solution in the vessel 20I begins to absorb the water vapor which is pro- 7 That means duced in the vessel 2| l. The heat necessary for developing this water vapor is delivered from the ground water 2l0 which is pumped with the aid oi the pump 2" to the jacket of the evaporator 5 2H and returns through the pipe '2l8. The heat of absorption developed in the absorber 2M is discharged to the waterin the pipe 202, thus producing water vapor in the accumulating system. After the 'water in the evaporator 2 is 10 evaporated and the'alkali solutiondn theabsorber 2M diluted, the discharging process is finished and the reverse process has to take place as described inthe last paragraph. i

In Fig. 5 is shown an embodiment of our invention as applied to an absorption refrigerating apparatus of the intermittent type in heat exchange with another absorption apparatus of the intermittent type used as cold accumulator. 22l denotes the absorber-generator of an intermittently operating absorption refrigerating apparatus in which a solid absorbent, for instance, calcium chlorid is utilized.

A heating element 222 applies heat to .the absorber-generator HI and is connected to the supply circuit my through a contact making clock 223. 224 is the air-cooled condenser of the apparatus. During the generating period the liquid refrigerant passes from the condenser 22l into an intermediate container 226 to which an evaporator coil 228 placed ina cold storage tank225 is con-' nected.

As soon as theheating element 222 is deener-' liquid refrigerant evaporates in the gized the evaporator 228 which supplies cold to the storage tank 225. The vapor returns to the absorbergenerator 22l where it is reabsorbed.

Although the evaporator 228 is located in the cold storage tank 225, variations of temperature in the cooling chamber occur insuch an apparatus, since no refrigeration is produced at all during the heating. period. .In order to avoid the variations of temperature another intermittently operating absorption refrigerating apparatus is provided whose condenser-evaporator 23l 45 is located in the cooling chamber, whereas its absorber-generator 230 is arranged above the refrigerator. The absorber-generator 230 is not provided with a heating element as is the case with the absorber-generator 22].

The last-described additional absorption apparatus230, 23l acts as a cold accumulator. The air in the cooling chamber circulates in the direction or the arrows, as shown in Fig. 5, during the absorption period of the apparatus produc- 55 ing refrigeration. A baiile plate 235 divides the cooling chamber in such a manner that the circulating air passes alongthe condenser-evaporator23l 'ot the accumulator apparatus placed in the cooling chamber. The condenser-evapso orator 2M is'provided with outer heat radiating ribs 234'. By the cooling effect brought aboutduring the absorption period of the absorption apparatus proper, the pressure in the interior of the accumulator apparatus is decreased so that the:

65 refrigerant is expelled in the latterirom the solid absorbent contained in the absorber-generator. In this case the refrigerant vapor escapse into a conduit 223 through an inner perforated conduit and reaches the condenser-evap- 70 orator 23l where it is llquefled.'

The condenser-evaporator 23l of the accumulator apparatus which has acted as condenser duringthe absorption period oi the absorption 1 apparatus proper-now operates as evaporator 75 during the heating period of the absorption ap- 'paratus proper since the temperature now rises in the cooling chamber. The condenser-evap orator 23l prevents, owing to the refrigeration produced thereby, an undue rise of temperature in the refrigerator during the generating period of the apparatus proper. The air in the cooling chamber then circulates in opposite direction- Consequently, by this system the temperature in the cooling chamber is prevented iromattaining 'too high a value during the generating period of the absorption apparatus proper and from'dropping to too low a value during the absorption period without consuming unnecessary cold or heat energy.

As already stated in the introduction, the heat converter combined with 'an intermittently operating absorption apparatus to form a system .may also consist of a thermal power plant; In such combinations, it is possible to utilize great diflerences in temperature for producing mechanical energy in thermal power plants by approaching as far as possible the reversible transformation cycle without exposing the parts of the thermal power plant to extremely high or lowtemperatures'. In general, it is possible to associate in this case the intermittently operating apparatus with the thermal power plant in one or more points of the apparatus so as to cause aheat exchange with one another. An apparatus of the intermittent type may, for instance, be combined with a thermal power plant in such a manner that a heat exchange occurs either during the generating period of the intermittently operating. apparatus or during the absorption period. In the first case heat may be, for instance, supplied by the condenser of the intermittently operating apparatus to a heat absorbing part of the thermal power plant or, for instance bleed steam, of the thermalpower plant, may be utilized for heating the generator of the intermittently operation absorption apparatus. Should the thermal powerplant be in heat exchange with the absorptionapparatus during the absorption period, the absorber of the intermittently operating apparatus may be in heat exchange with a heat absorbing part; for instance with a steam generator of the thermal power plant, or the evaporator of the intermittently operating apparatus in heat exchange relation with a heat radiating portion of the power plant; for instance with a condenser. In this case, for instance, a heat exchangebetween the absorption apparatus of the intermittent type and the power plant is also possible in two .points of the absorption apparatus. Finally, it is also possible to cause a heat exchange between the thermal power plant andtheintermittently operating absorption apparatus during the generatingperiod as well as duringthe absorption period.

Fig. 6 illustrates a plant which comprises three turbines of difleren't'pressure stages. Two of the intermittently operating absorption apparatus 1 are connected to the turbine of the highest pressure stage and the other two to the turbine 01 the lowest pressure stager The high-pressure steam generator of the plant is designated ,by the reference character D. To the steam generator D a superheaterU is connected, from which a steam conduit 2 leads to the high-pressure turbine T1. The exhaust steam conduit 30,2 of this turbine branches oil? at point 303. A portion of the exhaust steam passes from this point to the medium-pressure turbine T1 through a conduit 304, whereas the remaining portion of the exhaust steam flows to 75 erator ZW. The steam produced in the latter reaches the point 3|3 through a conduit 3 at which point the exhaust steam conduit 3l2 of the medium pressure turbine T2 enters. The conduits 3| l and 3l2 join at point 3|3, whence the vapor flows into the lowpressure turbine T3 through a conduit 3. As soon as the steam expands in the turbine T3 it passes as exhaust heat through the conduit 3l5 into the condenser C: where it is condensed. The condensate then flows through a conduit 3| 6 into a feed pump P, which feeds the condensate back into the high-pressure steam generator D through a conduit 3ll, a preheater VW and a conduit 3| 8.

The thermal cycleof the operating medium of the turbines is in heat exchange in a series of points with heat radiating and heat absorbing parts of the four intermittently operating absorption apparatus, that is to say heat is imparted to the high-pressure steam generator D and to the intermediate pressure steam generator ZW from the heat radiating parts of the absorption apparatus, whereas heat is abstracted from the intermediate pressure condenser C1 and the condenser C2 by the heat absorbing parts of the absorption apparatus. The absorber-generators of the four intermittently operating ab sorption apparatus are designated by the reference characters A1, A2, A3, A4 and the corresponding condenser-evaporators by K1, K2, K1, K4. The conduits between each absorber-generator and the corresponding condenser-evaporator are designated by the numerals 32l to 324. In bringing about a heat exchange between the absorption apparatus of the intermittent type and the thermal power plant, various systems for the transfer of heat are provided which transfer the heat by means of circulating liquids. For the circulation of the liquids, pumps P1, P2, P3, P4, P5, P6, P1, P8 are employed. In all heat radiating or heat absorbing parts of the plant either coils built in these parts or jackets surrounding these parts are provided for the transfer of heat through which the circulation of the liquid takes place. The system is so designed that the absorber-generators A1 and A2 of the absorption apparatus in heat exchange with the high-pressure portion of the thermal power plant receive their heat of generation from a heating boiler H and that further their heat of absorption is supplied to the high-pressure steam generator D. Similarly, the heat of condensationevolving in the condenser-evaporator K1 and K2 is supplied to the high-pressure steam generator D, whereas the heat required for the evaporation is supplied to the condenser-vaporators K1 and K2. by the intermediate pressure condenser C1 of the thermal power plant The absorber-generators A3 and A4 or the'absorption apparatus of the intermittent type in heat exchange with the low-pressure portion of the thermal power plant receive their heat of generation from the condenser 02 of the thermal power plant, whereas the 'heat of absorption of said absorber-generators is supplied to the intermediate pressure steam generator ZW. The heat of condensation is supplied by the corresponding condenser-evaporators Ka-and K4 to a cooler K, whereas the heat of evaporation to the condenserevaporators K3 and K4 by the condenser 02 of the thermal power plant. 4

To ensure a continuous operation of the heatexchange devices, two absorption apparatus of the intermittent type are always operating together in such a manner that one apparatus has its generating period while the other has its absorption period. The liquid circulating systems which serve to transfer the heatbetween heat converters are periodically reversed. To this end, a series of valves designated in Fig. 6 by the reference characters V1, V2, V3 to V12 are employed. These valves assume alternately in a given period always the position shown in the figure or a position obtained by a rotation of 90 in a counter-clockwise direction.

In the valve position as shown in Fig. 6 the absorber-generator A1 is heated by the heating boiler H. The latter is heated by an outside source of heat 326,- whereby the liquid for the transfer of heat contained therein is heated. It passes through the valve V3, a conduit 33l into a jacket 332 surrounding the absorber-generator A1 andthence, driven by the pump P1, back to the heating boiler H through the valve V1 and a conduit 333. As a result of the heating of the absorber-generator A1, the operating 'medium contained therein passes off from the solution in the form of gas and reaches the condenserevaporator K1 through the conduit 32!. From the condenser-evaporator, the heat of condensation is supplied by the following circulation of liquid to the high-pressure steam generator D. The liquid circulates, driven by the pump P4,

through the .valve- V5, a conduit 365, a conduit through a valve V2, a conduit 345, a conduit 336, a heating coil 331 located in the high-pressure steam generator D, a conduit 3 and through a jacket 342 surrounding the absorbergenerator A2 back into the pump P2.

Simultaneously heat of evaporation is supplied from the intermediate pressure condenser C1 to the condenser-evaporator K2. For this transfer of heat a circulating liquid is utilized which, driven by the pump Pa, passes through the valve V4, a conduit 353, a cooling coil 358 located in the intermediate pressure condenser C1, the valve V6, a conduit 35! and a jacket 352 surrounding the condenser-evaporator K2 back into the pump P3.

The operation of both absorption apparatus in heat exchange with the low-pressure turbine T3 is in the valve position as shown in the drawings as follows:

The absorption apparatus A3, K: has its generating period, since the absorber-generator A3 is heated by the condenser C2 of the thermal power plant by a system in which a liquid circulates, the circulation being brought aboutby the pump P7. This system may be traced from the pump P7 through a jacket 3" surrounding the absorber-generator A3, a cooling coil 313 placed in the condenser C2 and through the valve V11 back to the pump P1. The corresponding tion with a low outside temperature. The system is traced from the pump Pa through a jacket 311 surrounding the condenser-evaporator K3, the valve V1, the cooler K, the valve V2 back to the pump Pa.

The fourth absorption apparatus A4, K4 has its absorption period in the position of valve shown in Fig. 6. The absorber-generator A4 is cooled by circulating liquid which transmits the 7 evaporator K4, a cooling coil 312 placed in the condenser C2 and the valve Va back to the pump P5.

The absorption apparatus are operated in such a manner that the generating and absorption periods have the same duration. The valves V1 to V12 are rotated 90 in the counter-clock direction at the end of an operating period. By this reversal of the valves, the liquid circulating systems, in which the absorber-generators and the condenser-evaporators of the absorption apparatus of the intermittent type are in heat exchange with the heat' absorbing and heat radiating parts of the thermal power plant are reversed in such a manner that the absorber-generators A1 and A3 now operate as absorbers and theabsorber-generators A2 and A4 as generators.

Accordingly, the liquid circulating systems ofthe' condenser-evaporators with the valves in the reversed position are connected in such a manner that the condenser-evaporators K1 and K3 now operate as evaporators and the condenser-evaporators K2 and K4 as condensers.

Without further tracing the liquid circulating systems for this valve position, it will be apparent from the drawings that the absorber-generator A2 in the new valve position receives its heat of generation from the heating coil H. The condenser-evaporator K2 transfers the heat. of condensation to the high-pressure steam generator D. The absorber-generator A1 transmits its heat of absorption to the high-pressure steam generator D and the condenser-evaporator K1 receives the necessary heat of evaporation from the intermediate pressure condenser C1. The absorber-generator A: transfers its heat of absorption to the intermediate pressure steam generator ZW. The corresponding condenser-evaporator K3 receives its heat of evaporation from the condenser C2; finally the absorber-generator A4 receives the heat of generation from the condenser C2 and the corresponding condenser K2 transfers the heat of condensation to the cooler K.

As'operating medium for the thermal power plant, waterwapor might be utilized. Both heat converters operatingwithin the lower temperature range (absorption apparatus of the intermittent type A3, K3 and A4, K4) may be, for in-' stance, operated with a solution of ammonia and water, whereas the heat converters operating within the higher temperature range (absorption apparatus of the intermittent type A1, Kr and A2,

m may'b'e operated with aqueous sodium hyignated by the numerals 38I droxide solution. In the system for the transfer of heat brine may be, for instance, em-..

ployed for the lower temperature range, whereas for the higher temperature range oils of high boiling point, for instance, paraffin oil, are em-' ployed to advantage. The expansion vessels des- 384 are connected to the highest points of the four systems forthe transfer of heat.

In the systems shown in Figs. 2 and 6 intermittent absorption refrigerating apparatus are principle from that of the usual intermittent absorption refrigerating apparatus. In the latter the generator-absorber is heated by a. heat source (for instance an electric heating element) during the generating period, whereas the condenser is in heat contact with a cooling medium. During this period ahigh pressure prevails inv the apparatus hitherto employed. During the absorption period the evaporator is in heat contact with the cooling chamber air. Thisalso employed, the operation of which differs in air serves as a heat source, whereas the generator-absorber is in heat exchange relation with the cooling medium so that the latter takes up heat from the generator-absorber. During this period the lower pressure prevails in the known apparatus.

In contradistinction thereto intermittent ab-- sorption apparatus are employed in the systems disclosed in Figs. 2 and 6 in which'apparatus the lower pressure prevails during the generating period and the higher pressure during the absorption period. The generating process is then brought about by bringing the condenser evaporator in ,heat contact with the cooling medium of lower temperature, whereas the generator-absorber is in heat exchange relation with a heat source of mean temperature. Under these operating conditions, the refrigerant taken up by the absorbent evaporates, passes into the condenser and is liquefied therein. During the absorption period the condenser-evaporator is brought -into heat-exchange relation with the heat source of the mean temperature and the generator-absorber then forms a heat source of this case, it is of a particular advantage that the high temperature of the medium heated by the heating vessel H or of the media operating in the absorption apparatus do not come into contact with the steam power engines. A further advantage lies in the fact that the steam need not be expanded to the pressure corresponding to the low surrounding temperature, which cannot be eifected economically owing to the very large volumes of steam. It is, consequently,, possible in the above-described manner to utilize predetermined differences intemperature of. very high value in an approximately reversible manner, so that the temperature of the operating medium does not reach the limit temperatures.

Finally, absorption apparatus of the intermittent type may be applied to advantage also in combination with continuously operating apparatus for carrying out a conversion of heat in various manner. In Figs. '7 to 10 are illustrated four embodiments of the invention in a diagrammatic form for the above sphere of application.

Fig. 7 shows the combination of a continuously operating absorption refrigerating apparatus with an absorption apparatus of the intermittent type for the transfer of heat and the production of refrigeration. 40! denotes the absorber-generator of an intermittently operating absorption refrigerating apparatus which operates with a liquid refrigerant. The heating of the absorbergenerator is effected by a heating element 402. During the generating period the ammonia vapor reaches a vessel 404 serving as condenser through a conduit 403 connected to the top of the absorber-generator, an intermediate vessel 439 and a conduit 440. The condenser 404 is surrounded by a cooling jacket 405 which is connected through circulation conduits 406 and 40! with a heating body 408 located in the heat insulated generator 42! of the continuously operating absorption apparatus to form a closed system for the transfer of heat. In this system a liquid is contained which upon taking up the heat of con densation of the intermittently operating apparatus evaporates in the lower part 405 andis again condensed by the radiation of -heat in the upper part 408. In this manner the heat of condensation of the intermittently operating apparatus is utilized for heating the generator 42! of the continuously operating apparatus. The refrigerant of the apparatus of the intermittent absorption type flows from the condenser 404 through a conduit 448 connected to the lower part thereof into an evaporator 449, where it is-collected.

Asa result of this heating the refrigerant is driven off from the rich solution contained in the generator 42!. "The refrigerant vapor passes through a percolator pipe 423 together with the weak solution raised by the refrigerant vapor into the heat insulated gas separating chamber 424, where the refrigerant vapor is separated from the weak solution. The refrigerant vapor then passes through the conduit 425 into a condenser 426 where it is condensed, the condenser 426 being arranged in an air shaft 2. The liquid refrigerant flows through a conduit 42! into the evaporator 43! which is placed in another air shaft 3. The conduit 42! leading from the condenser 426 to the evaporator 43! has the form of a U-shaped conduit, whose descending portion is'connected to the bottom of the condenser-426 and whose rising portion 429 is enlarged before entering the evaporator 43! to a branch vessel 430. The latter is in turn connected to the lowest point of the conduit leading from the condenser through a U-shaped conduit 428. The U-shaped conduit system provides for a difference in pressure between the condenser and the evaporator.

The vaporous refrigerant passes through a conduit 432 into the lower part of an absorber 433 in which the weak solution from the gas separating chamber 424 and passing through the U-shaped conduit 434 flows downwardly in opposite direction to the vaporous refrigerant. Here the refrigerant is reabsorbed by the weak solution and the rich solution flows from the bottom of the absorber through the conduit 435, the heat exchanger 44! and a conduit 44la into a heat-insulated storage tank 435 and thence passesthrough a U-shaped conduit 43'! back into the generator 42!.

The heat exchanger 44! is disposed on the one hand in the conduit 435 leading from the absorber 433 to the storage vessel 436 and on the other hand in the conduit 434 leading from the gas separating chamber 424 to the absorber 438 is In order to carry off the heat of absorption the absorber-generator 40! is surrounded by a cooling jacket 409 in the upper part of which a circulation conduit 442 is connected which leads through a valve M to the upper part of a return cooler 4!! arranged in the air shaft 4!2.'

From the lowest end of the return cooler 4!! a conduit 443 extends to the lowest point of the jacket 409. In this closed circulating system a liquid is contained which evaporates upon taking up the heat of absorption of the absorber-generator 40! and which is cooled by the air rising in the air shaft 4l2. This system for the transfer of heat is put into operation at the beginning of the absorption period by opening the valve 4!0. For actuating the valve 0 an electromagnet 444 is provided which is connected to the supply circuit 446, 44'! in parallel relation with the heating element 402 through a contact making clock 445. The system for the transfer of

heat

405, 406, 401, 408, which heats the generator of the continuously operating absorption apparatus during the generating period of the intermittently operating absorption apparatus is not in operation during the absorption period. Consequently, an electric heating element 422 arranged in the generator 424 must be energized if an uninterrupted operation of the continuous absorption apparatus is to be maintained. The heating element 422 is, therefore, also connected in parallel relation with the'heating element 402 and the magnet 444 to the contact making clock 445.

Owing to the cooling down of the absorbergenerator 40! the pressure decreases in the intermittently operating absorption apparatus so that the liquid refrigerant evaporates again in the evaporator 449 and from which it returns to the intermediate vessel 439 through the conduit 448', the condenser 404 and the conduit 440. From the intermediate vessel 439 the vaporous refrigerant is introduced into the weak absorption solution contained in the absorber-generator 40! through the conduit 450. The evaporator 449 is also provided with a .jacket' 4!4 similar to that ofthe condenser 404. The jacket M4 is connected with a heat-transfer apparatus 4|5 disposed in the air shaft 3 through circulation conduits 45!, 452 to form a closed system for the transfer of heat. By this system the heat of evaporation of the absorption apparatus of the intermittent type is abstracted from the air flowing in the shaft 4 !3 during the absorption period. In order to avoid losses of heat or refrigeration the

vessels

404 and 449 are heat insulated. The evaporator 449 of the intermittently operating absorption apparatus is so designed that the liquid solvent entrained into the evaporator during the generating period flows automatically again into the absorber-generator 40!. To this end, partitions 453 and 454 are arranged in the evaporator 440 which conduct the liquid refrigerant in a given direction through the evaporator vessel 449. The upper partitions 453 are provided with openings 455 through which the refrigerant vapor flows during the evaporation. The solvent entrained into the evaporator is gradually forced towards the outlet of the conduit 456 by the liquid refrigerant flowing into the only apparatus. parts 5, 43l which abstract "paratus may be employed accordingly, both for heat from the air flowing in this shaft. Here a cold current of airconsequently flowsv in the direction of the arrow. The corresponding apmentioned heating body provided for heating.

the generator, .whereas the apparatus of the absorption intermittent type connected to the heating body 408 produces refrigeration. Both absorption apparatus of the intermittent type required in this case must be accordingly so operated that their operating periods are timely displaced, that is to say one apparatus hasits generating period while the other operates during the absorption period and reversely.

Fig. 8 shows an absorption apparatus of the intermittent type in heat exchange with a continuous absorption apparatus in two points of the absorption apparatus of the intermittent type for the production of refrigeration of two different temperatures, one of which is particularly low. The continuously operating apparatus contains ammonia as refrigerant and water as solvent. The reference characters in Fig. 8 are the same as those in Fig. '1 as far as like apparatus parts are concerned. 460 denotes the absorber-generator of the absorption apparatus of the intermittent type. absorbent, for instance, strontium bromide, saturated with ammonia. During the generating period the absorber-generator 460 is heated by 463 through the conduit 462.

' is open during the generating period of the intermittently operatingabsorption apparatus and closed during the absorption period. By this system the heat of condensation is transferred from the condenser-evaporator 463 to the gen-, erator'42l by alternate evaporation in the evaporator 464 and subsequent condensation in the condenser 465. Besides this exchange of heat between the last two mentioned parts, there also exists another'system for the transfer of heat.

between both apparatus. The absorber-genera tor 460 of the absorption apparatus of the intermittent typeis surrounded by a cooling jacket 461 which is connected with a condenser 468 ar- It is filled with a solid 7 ranged in the evaporator 43l of the continuous absorption apparatus through two circulation conduits 469', 418. A valve 41I arranged in the circulation conduit 410 is closed during the generating period and brought to an open position a during the absorption period. By the medium circulating in the above-described system for-the transfer of heat, the absorber-generator of the intermittently operating absorption apparatus is cooled by the evaporator 43f of the continuous absorption apparatus. From the evaporator 412 of the continuous absorption apparatus the refrigeration produced by the continuous absorption apparatus is transferred to the cooling chamber 414 by a system for the transfer of heat which consists of an evaporator 413 located. in the cooling chamber: 414 and of a condenser 415 disposed in the evaporator 412 being connected by two circulation conduits 416, 411. The refrigeration produced by the condenser-evaporator 463 of the absorption apparatus of the inter. mittent type is transferred to another cooling cha ber 48!! by means of a similar transfer system 18, 419.

The embodiment shown in Fig. '7 difiers from the continuous absorption apparatus in that the latter in the present case operates with an admixture of an inert gas in the evaporator and absorber. The evaporator 412 forms with the absorber 433 together with two gascirculating conduits 413i, 482 a system in whichthe gas mixture circulates in the direction of the arrow in a well-known-manner. To cause a circulation of gas mixture refrigerant. vapor is employed which is supplied to a nozzle 484 through a conduit 483 which is branched ofi the conduit 425.

rator 412 of the continuous operating apparatus,

refrigeration of relatively lower temperature is produced as compared to the temperature prevailing in-the evaporator 412 of the continuous absorption apparatus. Accordingly, the temperature of the cold! transferred to the cooling chamber 48!! is particularly low.

In the system shown in Fig. 9 an absorption apparatus of the intermittent type is employed as heat accumulator in connection with a continuous absorption apparatus.

In a heat-insulated generator 58!, heated by an electric heating element 502 a rich solution, for instance, an aqueoussodium hydroxide solution, iscontained therein, from which the water is driven off by application ofheat. The water vapor thus expelled raises the hot solution through a small percolator pipe ll3 to a gas separating chamber 584, where the absorption solution is separated from the vapor. The solution flows from the gas separating chamber 584 through av U-shaped conduit 505 into the upper part of the absorber 506 in which the solution trickles downwardly over bafile plates 501 arranged therein. The refrigerant vapor is supplied from the gas separator 504 through a conduit 508, in which an intermediate vessel 509 is inserted to an air-cooled condenser 5I0 designed in the form of a coil and connected by a conduit 5 with a small vapor separator 5l2. A U-shap'ed return conduit 5l3 leading from the .vapor separator 5l2.to"the lowest part of the condenser 5"] provides for a column of liquid refrigerant in the conduit 5| l. The liquid refrigerant passes from the container 5l2 through a conduit 5l4 into the evaporator 5l5 which is prodrug the absorber-generator, a coil vided inside with baflle plates and outside with ribs 5H. A connecting pipe 5l8 conveys the refrigerant vapor from the lower part of the evaporator 5l5 to the absorber 506 where it is taken up by the weak absorption solution trickling downwardly. The absorber 506 is provided outside with cooling ribs 5| 0 which assist the dissipation of heat of absorption to the surrounding atmosphere. The enriched absorption solu tion flows back to the generator 50l through a U-shaped liquid conduit 52l connected to the pipe 5M and being in heat exchange with the U-shaped conduit 505. Within the absorber 506 extends in the central portion thereof a liquid collecting vessel 520 which projects for some distance above the absorber and forms the condenser-evaporator of an intermittently operating absorption apparatus. The walls thereof consist of a metal which has a good heat conductivity. 5223 denotes the absorber-generator of the absorption apparatus of the intermittent type. It consists of a pressure-tight container which is formed in a tubular outer jacket the bottom plates 52d and being welded thereto. The interior of the generator is traversed by a gas perforated conduit 525 to which heat conducting cross-ribs 52? are connected which are also in a good heat conducting contact relation with the interior walls of the absorbergenerator. The cells formed by the cross-ribs are filled with a solid absorbent, for instance calcium chlorid, which is saturated with ammonia as operating medium. In order to heat the absorber-generator, a liquid system is employed which consists of a jacket 523 surround- 525 wound around the heating element 502 of the generator 50!, and of two conduits 530 and EM. An expansion vessel 533 is connected to the highest point of the circulating system through a conduit 552. A conduit 53d leading to the upper portion of the condenser-evaporator 528 is connected to the perforated conduit 525 of the generator.

The heat is stored up in the following manner: Thegenerator 5M is heated, on the one hand, by the heating element 502 so that the continuous absorption apparatus is put into operation, and at the same time the circulating liquid contained in the coil 529 is heated so that the liquid begins to circulate and heats the absorber-generator 522 indirectly. Consequently, the operating medium passes oil fromthe chemical compound contained in the absorber-generator 522 and reaches the condenser-evaporator 520 provided with cooling ribs 535 through the conduit 534. By the cooling effect of the air the operating medium is condensed and collects in the lower part of the condenser-evaporator,

Since the temperature inside thegenerator 505- is relatively high as a result of Heat of absorption developed a portion of the liquid operating medium evaporates again in the 'lower part of the condenser-evaporator 520 surrounded by the absorber 506. The vapor condenses again in the upper air-cooled portion of the condenser-evaporator 520. In this manner the heat of absorp- The electric heating element of the generator 501 is energized until the operating medium is driven off from the generator-absorber 522 and collected in the condenser-evaporator 520 as liquid operating medium. As soon as the heating element of the generator 50! of the continuous absorption apparatus is deenerglzed, the circulation of liquid between the coil 529 and the Jacket of the absorber-generator 528 is brought gradually to rest, so that no more ammonia vapor is driven off from the absorber-generator 522. The operating medium contained in the condenserevaporator 520 diminishes gradually by evaporating slowly, owing to the heat of absorption taken up from the absorber 596 of the continuous absorption apparatus. The ammonia vapor flows back through the conduit to the absorbergenerator 522 where it is reabsorbed. The heat resulting from this absorption is given up to the circulating liquid contained in the jacket 52%) so that the liquid now circulates in the opposite direction, thus heating indirectly the rich solution contained in the generator 505. In this the development of the refrigerant vapor in the continuous absorption apparatus will not be in terrupted, notwithstanding that the heating element 552 is deenergized. Accordingly, the condenser 550 is further charged with refrigerant vapor and the evaporator with liquid refrigerant. The production of refrigeration is, therefore, also continued as long as the heat required for the generation is evolved by the absorption of fresh quantities of ammonia vapor in the absorbergenerator 522.

In the above-described manner, the periods of the heat storage (and of the application of heat to the generator 50! by means of the heating element 5G2) and the periods of regeneration of heat (and of the application of heat to the generator 506 by means of the coil 529) alternate continuously with each other.

In the system shown in Fig. 10 an intermittently operating absorption apparatus is in heat exchange with a continuous absorption apparatus, whereby the storing up of energy of intermittently operating absorption apparatus is utilized in a special manner for the operation of a continuous absorption apparatus in a similar manner as in the preceding embodiment. In this case, a system for the direct heating of the generator is provided only for the absorber-generator of the absorption apparatus of the intermittent type but not for the generator of the continuous apparatus. The operation of this system is as follows:

During the generation period the heating element 602 of the absorber-generator GM of the intermittently operating absorption apparatus is energized. The operating medium thereby passes off from the absorber-generator 60E in the form of gas through a conduit 603 and is liquefied in the condenser-evaporator 604. The heat of condensation isutilized to heat indirectly during this period the

generator

605, 606 of the continuous absorption apparatus. To this end, a system for the transfer of heat consisting of a heat absorbing body 60! located in the condenser-evaporator 604 and of a heating body 608 disposed in the generator 606 is provided. The conduit connecting these two parts 601 and 608 is provided with a valve 609 which during the generating period of the absorption apparatus of the intermittent type is brought to the position as shown in Fig. 10. The-conduit between the parts 601 and 608 of the system for the transfer of heat is partly designed as a heat transfer coil 6I0 which is in heat exchange relation with the percolatorcoil m which forms a part of the conduit BIZ leadin from the absorber-6| I to the generator 608. The liquid operating in the transfer system 601, 60., till heats the liquid in the coil 80! so that gas bubbles are developed therein which convey the rich solution to the gas separator 806' in which a further generation takes place owing to the heat evolved by the heating body 808.

During the absorption period, the heating element 602 is deenergizeh and the valve 609 is rotated 90 in the clockwise direction. In this manner a cooling jacket 6|3 surrounding 'the absorber-generator Bill is insertedin the system for the transfer of heat instead of the cooler 60! located in'the condenser-evaporator 604 so that the solution passing into the gas separatbr is heated, as was previously the case with the heat of condensation, by the heat of absorption.

The circulation of the refrigerant in the continuous absorption apparatus takes place as follows:

The vaporous refrigerant expelled in the coil- 605 and in the gas separating *chamber 606 reaches through a rectifier 628 and a conduit 6 the water-cooled condenser 6L5 where it is The liquid refrigerant flows from the condenser it! through a conduit, 616 into a the evaporator 6". Between the latter and the equally water-cooled absorber 6 two conduits 618, M9 are provided, in which the inert gas circulates in order to convey the vaporous refrlgerant from the evaporator Gil to the absorber 6. The conduits H8, H9 may be in heat exchange with one another. The richsolution then returns in'the above-described manner from th absorber 6H to the gas separating chamber 606 through the conduit 6I2 connected to bottom of the absorber oil. In order to cool the absorber 6H and the condenser Sllwater is used which flows from a conduit 62!! through a cooling jacket 62! surrounding the absorber 6H and thence through a conduit 622 to the container 623 in which the condenser 615 is disposed, whence the water passes through a conduit 824 into a coil 625. The latter is in heat exchange relation with another coil 626 which forms together with aheat-transfer'body 621 arranged in the condenser-evaporator Bill a closed system for the transferof heat. The liquid contained in this system isheated by the cooling water and thereby caused to circulate. In this case, the heat supplied to the condenser-evaporator 804 during the absorption period serves to evaporate the liquid operating medium. I

The advantage of this embodiment of our invention consists in the fact that the generator. of the continuous absorption apparatus needs no direct heating. To heat the same, the heat of condensation and of absorption of the inter-.

mittently operating apparatus is alternately utilized which must be heated only during the generating periods. Such an operation is, for instance, of particular advantage if in operating the system forthe production of refrigeration electricity is available at low rates during the night, without interrupting, however, the production of refrigeration. a

In case a continuousabsorption apparatus and an intermittently operating absorption apparatus are employed in the same system for the production of refrigeration the system may be so designed that the continuous absorption apparatus serves to supply refrigeration during the gener- 5 rating period to the refrigeration cabinet which accepts from the operation of an absorption apparatus of the intermittently operating type.- Finally, it

is also possible to combine in a system a'con-- tinuous absorption apparatus and an absorption apparatus of theintermittent type in such a manner that a periodically increased production of refrigeration required for a refrigeration cabinet which is cooled by means of the continuous absorption apparatus is effected by the intermittently operating absorption apparatus during the absorption period.

In all the above-described embodiments are "shown intermittently operating absorption apparatus in which a vaporous refrigerant is con densed and the liquid refrigerant is again evap- -.orated. Intermittently operating absorption apparatus may also be employed in which the operating medium is liquefied in a solid or liquid absorbing medium from which it is again evaporated during the absorption period. Instead of continuous absorption apparatus, in which the operating medium is liquefied in the condenser, resorber apparatus maybe employed, in which the operating medium is liquefied-in a solution, a

from which it is again evaporated without departing from the spirit and scope of the inven tion.

We claim as our invention:-

1. In a system in which a thermal power plant is. associated with an intermittently operating absorption apparatus, comprising a generator and absorber, means for heating said generator during the generating period by the steam of the power plant, said means being so arranged as to condense. during the heating period the steam of the thermal power plant, said absorber being so arranged that it gives up its heat of absorp tion to the condensate of the thermal power plant toevaporate the condensate.

2. In a system for the conversion of heat, comprising several heat converters at least two of which being intermittent absorption apparatus operating with diiferent absorbents and working media and another being a thermal power plant, each having a unit in which the vaporous operating medium passes from the vaporous state to another state of aggregation and an operating medium vapor developing unit, heat-exchange means between said absorption apparatus and said plant, said means being so arranged asto cause the heat liberated in the first-named unit of one of said converters to be supplied to the last-named unit of the other of said converters for the development of the operating medium vapor.

3. In a system for the conversion of heat, comprising several heat converters at least one of which being an intermittent absorption apparatus and another being a thermal power plant, the absorption apparatus of the intermittent type comprising an absorber-generator and a condenser, means for heatingsaid absorber-generator, and means for giving up the heat-of condensation developed in said condenser to a heat absorbing part of the thermal power plant.

4. In a system for the conversion of heat, comprising several heat converters at least one of which being an intermittent absorption apparatus and another being a thermal power plant, the