Patent GB-449320-A (GB)
Title: Improvements in or relating to intermittently acting absorption refrigerating apparatus
IPC: F25B17/00
Filed: 1934-12-17
Abstract: 449,320. Refrigerating. ELECTROLUX, Ltd., Luton, Bedfordshire.-(Assignees of Platen-Munters Refrigerating System Aktiebolag ; 2, Norrmalmstorg, Stockholm) Dec. 17, 1934, No. 36136. Convention date, Dec. 16, 1933. [Class 29] Absorption systems.-In apparatus wherein liquor circulates during a generating period between an unheated storage vessel 10 and the generator 14 and during an ensuing absorption period between the storage vessel and an absorber 16, as described in Specifications 431,266, 447,398, and 447,399, [Group V], a liquid seal is set up in a conduit 42 during the generating period to prevent the flow of generated vapour to the cool liquor, and is broken during the absorption period to allow vapour to enter the cool liquor. The circulation of liquor to the generator and the setting up of the liquid column are effected by heat operated gas-lift pumping devices. The system includes an " equalizing " vessel 22, a liquor heat exchanger 12, a " buffer " vessel 19 above the storage vessel 10, rectifiers 34, 44, a condenser 45 and an evaporator 49 with an overflow 50 of known type. The system is initially filled up to the level I and heat is applied to a flue 41 within " pumping " coils 29, 26, and a heating coil 39, of which the lowest serves to effect circulation from the bottom to the top of a collector vessel 24, the next to circulate the liquor through the interchanger and the collector to the upper part of the generator proper, while the uppermost heating coil is connected to the lower and upper ends of the generator and serves solely to heat the liquor. Vapour passes from the generator through a pipe 36 to rectifier 34, where it contacts with liquor overflowing an annular space 35 on to baffle plates, and thence through the second rectifier 44 cooled by a jacket of condensed refrigerant and into the condenser 45. The pressure forces the condensed refrigerant up through a pipe 48 to the receiver 49 of the evaporator, which may be insulated and have exposed pipes depending from it. During this period liquor is raised by the pumping effect in coil 29 from the bottom of the collector 24 to the annular space 35, which communicates by conduits 32, 33 with the buffer vessel 29, and thereby maintains a liquid level in conduit 42 at the height of the overflow wall 31 in vessel 24 to seal the liquor system against entry of vapour. Towards the end of this period overflow of liquor from the evaporator takes place through pipe 51, which at the point 52 receives heat from the equalizing vessel 22. After a time, condensed refrigerant passes down the pipe 51 and is vaporized at the point 52 and absorbed at the point 43 in the conduit 15 connecting the storage vessel with the absorber, and the heat of absorption influences a thermostat 53 to cut off the supply of heat to the generator. The pumping devices cease to operate and liquor flows through conduits 30, coil 29 and pipe 28 to collector 24, and liquor also flows from the buffer vessel through the absorber 16 and conduit 42 into the annular space 35. Conduit 42 is now open to the vapour space of the generator and also, through the rectifier 44 and pipe 48, to the evaporator, so that pressure rapidly falls and evaporation ensues with circulation of liquor through the conduits 15, 16, 18, the buffer vessel and the storage vessel. If, for example on hot days, the vapours are not completely absorbed in the absorber element 16, they will enter the buffer vessel and cause liquor to flow therefrom through conduit 33. When the level in the buffer vessel falls to the mouth of conduit 33, a vapour bubble or plug enters the conduit and thereby reduces the effective head of liquor inducing flow of vapour from the evaporator. This enables the absorber to deal with all the vapour and liquid will again rise in the buffer vessel to increase the effective head. When all vapour has been absorbed the thermostat cools down and again starts the supply of heat. The buffer vessel is provided with a vent pipe for the removal of foreign gases.