US2174482A - Method of operating a compression refrigeration system - Google Patents

Description

P. SCHLUMBOHM Sept. r26, 1939.

METHOD 0F OPERATING A COMPRESSION REFRIGERATION SYSTEM Original Filed Nov. 19, 1932 Patented Sept. 26, 1939 PATENT OFFICE METHOD OF OPERATING A COMPRESSION REFRIGERATION SYSTEM Peter Schlumbohm, New-York, N. Y.

original application November 19, 1932, sei-iai No. 643,344. Divided and this application February 23, 1938, Serial No. 192,167.

vember 25, 1931 I 2 Claims.

Following my invention, frozen cooling medium 10 is applied within the condenser, so that the vapor of the compressed refrigerant may contact directly the surface of the frozen cooling medium. The great advantage of this step will be evident from the following calculation: If the'frozen l5 cooling medium would be applied from thev outside of the condenser wall, some fi've to ten cen- 'tigrades would be lost for the heat transfer through the condenser wall;l If water is the refrigerant and water ice is the cooling medium,

2 this means that in the case of my method the true vapor pressure of water ice,.4.5 mm. Hg, would represent the condenser pressure, whereas in the other case the condenser pressure might easily rise, to pressures like 9 mm. Hg.

25 Assuming that the water-refrigerant is evaporating in the evaporator at a pressure of 2.25 mm, Hg, the ratio of compression would-have to be 1:4 if the known art was-applied and could be reduced to 1:2 if my new method is used.

30 Lowering the ratio of compression is of special importance if the compressors, which are required to compress the refrigerant, are ofthe type of the centrifugal compressor or of the type of the jet compressor, and just these types 35 are applied with preference for handling the large volume of refrigerant vapors as to be handled per B. t. u. in the case of such refrigerants like water.

'I'he invention is illustrated diagrammatically,

40 partly in section and 'partly in view, in the acdenser 3. VThe suction tube of the compressor- In Germany Nois designated 5 and the pressure tube (exhaust) is designated 4. 'Ihe condenser 3 is filled with the frozen cooling medium I, which practically will be in most cases frozen`water. The frozen cooling medium is e. g. placed on ajgrili 6 to al- 5 low the melted cooling medium and the condensed refrigerant to drip off and to be withdrawn from lthe bottom of the condenser by means of a tube 1. Following my invention it is important to withdraw these liquids quickly 10 and constantly from the condenser before they would beA warmed up by the condenser walls and cause higher presures inthe condenser than the pressure of the frozen cooling medium, which in the case of -water ice is 4.5 mm. Hg. Following my invention this low pressure of 4.5 mm.. Hg is further protected against the higher pressure of the jet of a water jet pump I9 by providing a liquid column S in the syphon trap 2l. This arrangement makes it possible to withdraw liquids from-the 4.5 mm. Hg pressure domain of the condenser into the about 12 mm. Hg pressure domain of the water jet pumps suction chamber.

Following my invention, the low pressure in the condenser 3 is furthermore maintained by providing an air pump 2| to withdraw non-condensable gas like air through tube 9 from the condenser. The exhaust tube I0 of the air pump maybe connected to the suction chamber of the water jet pump I8, as illustrated, the latter one working as pre-vacuum pump for the pump 2|.

Having now described the nature of my new method and having given an example ofthe manner in which it may be performed, what I claim is:

1. 'I'he method of operating a compression refrigeration system in which refrigerant vapor is compressed and condensed in a. condenser in heat exchange with a cooling medium, comprising the 40 step of condensingthe compressed refrigerant vapor in direct contact with frozen cooling medium and absorbing the condensation heat of the refrigerant by the melting of the cooling medium.

2..'I'he method as claimed in claimv 1, com- 45 prising the additional step of constantly withdrawing from the condenser liquid refrigeran

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