GB298792A - Method and apparatus for producing solid blocks of carbon dioxide ice - Google Patents

Abstract

298,792. Thurston, A. P., (Drgice Corporation of America). March 5, 1928. Solidifying.-Solid carbon dioxide of high density is obtained in large blocks by freezing the liquid under a pressure of from 1500 to 2500 lb. per square inch, the liquid being pumped continuously at approximately freezing temperature into the freezing chamber to make up for contraction. The carbon dioxide is obtained from flue gases by compressing the purified gases in stage compressors 12, 15, 18, freezing- out water, and cooling to the liquefaction temperature in a heat exchanger 21, whence the liquid flows into a separating chamber 26. Nitrogen gas escaping is conveyed by a pipe 29 to a rotary expansion motor 30, where its temperature is lowered to -300‹ F and the gas passes to the freezing plant proper, being used to cool liquid ether by means of coils 45. From these coils the nitrogen passes to the heat exchanger 21, thence to the dehydrator 19, and escapes through pipes 50. The cooled ether circulates about freezing chambers 41 into which liquid carbon dioxide flows from the separating chamber 26, and by opening a valve 61 a small high pressure pump 60 comes into action to raise and maintain the pressure in the freezing chambers to the degree stated. The chambers 41 are slightly coned, so that the ice blocks drop out or are easily ejected when the bottoms are opened.