Патент USA US2406003код для вставки
Aug. 20, 1946. Y A w. DENNIS ~ ~¿406,003 METHOD AND APPARATUS FOR OBTAINING PURIFIÈD LIQUID OXYGEN Filed oct. 1, 1943 y ~ ATTORNEYS v Patented Aug. 20, 1946 2,406,003 w UNITED STATES PATENT oFFlcE METHGD AND APPARATUS FOR OBTAINING PURIFIED LIQUID OXYGEN v Wolcott Dennis, Darien, Conn., assigner Air Reduction Company, Incorporated, New toYork, vN. Y., a corporation of New York Application October 1, 1943, Serial No. 504,578 ’ 5 claims. (ci. fsa-115.5) This invention relates to the separation and re covery of pure liquid oxygen from atmospheric air by liquefaction and rectification, eliminated eñ’ectively. In the usual methods of separating oxygen from caps 8, eñ’ecting partial rectiñcation of the liquid air introduced through the pipe I6. A condenser section ii having a plurality of tubes I8 is provided in the column 5, and the va suitable for many uses. It is the object of' the present invention to pro vide a method and app which aii'ord a high yield of liquid >oxygen aratus free from impurities such as those mentioned. _ .another object of 25 formed in_the condenser tubes. l 9 is comparatively rich in nitrogen, since most of the oxygen has 30 been separated on the trays i in the form of liquid which accumulates in the vaporizer section i3. Th ` L panying drawing, illustrating an apparatus suit- ' able for the practice of the invention. In carrying out the invention, the air is ini 35 the separation-of the desired constituents. _ eiiiuent or waste gas escapes through a pipe 28 from the top of the column.Surrounding the condenser tubes I9 is a va 45 porizer section 2 ' is‘anexample auxiliary column> operatlng at low pressure, for a little above .column 5 is provided with is liquid contains the impurities hereinbefore mentioned. To remove the impuri 50 ties, the liquid is conveyed through a pipe 30 into the condenser section I1. oi' the column’5 where it surrounds the tubes I8. 'I'he liquid in the va porizer 29 is under relatively low pressure, but the liquid in the condenser section I1 is under a static head of the column of liquid in the pipe 30 55 and vaporizer section 29. 'I'he liquid is vaporized 2,406,008 section I1, affording oxygen in in condenser thethe vapor phase, free from impurities. The latter section il'. The vapor remain in the iscondenser conveyed through a pipe 3l to ~ 4 the static head o! th'e first body. vaporizing the liquid oxygen of the second body by heat ex change with vapors produced by the rectification and reliquefying the oxygen vapor by heat ex ' a coil 32 submerged in the liquid surrounding the change with the ñrst body ot liquid oxygen. 2. The method of recovering liquid oxygen tree tubes I9, and since this vapor is under the static from impurities by separation from atmospheric head provided as hereinbefore described, air which comprises separating nitrogen from the oxygen of the air by liquefaction and rectifica tion, thereby producing a first body of liquid oxy phase oxygen ` readily lìqueñed by heat exchange with the liquid in the vaporizer 29. The liquid oxygen product; is withdrawn from the coil 32 through a pipe 33 controlled by a valve 34 and is delivered to any suitable storage receptacle. - gen at a pressure slightly exceeding one atmos phere, delivering from the ñrst body to a second body lower level under the static head of the first body, vaporizing the nected to the condenser section l1 to permit with 15 liquid oxygen of the second body by heat ex drawal from time to time of liquid containing change with vapors produced by the rectification and reliquefying the oxygen vapor by heat ex impurities. Purges 31 and 38, controlled by valves 39 and 4D, similarly permit removal of liquid from change with the ñrst body of liquid oxygen. 3. In the method of recovering liquid oxygen the vaporizer sections i3 and 29. By locating the condenser section l1 in the 20 free from impurities by separation from atmos pheric air, the steps of maintaining two bodies high pressure column at a point below the main of liquid oxygen at different levels, the lower body oxygen vaporizer 28, it is possible by virtue of being subject to the static head of the upper body, the liquid head available, to vaporize the im vaporizing oxygen from the lower body and re pure oxygen product at suñ'icient pressure to cause the evolved vapor to condense in the con 25 liquefying the vaporized oxygen by heat exchange denser coil 32 by heat exchange with the liquid with the liquid of the upper body. 4. In an apparatus for recovering liquid oxygen surrounding the coil at lower pressure. Since all from atmospheric air, two superposed rectiñers, feeds to the low pressure column are substan a vaporizer at the bottom of the upper column, tially liquid and since the vaporizer is situated at the lower end of said column, it is possible 30 a vaporizer in the lower column, a connection be tween the two vaporizers whereby liquid in the to maintain a maximum of reflux thus ensuring lower vaporizer is subject to the static head of a high degree of rectification. The method and liquid in the upper vaporizer, andv a condenser apparatus as described afford a more eñicient pro in the upper vaporizer connected to the lower cedure and structure permitting the recovery o! vaporizer to receive and reliquefy the vapor de oxygen in a liquid form free from impurities and livered from the lower vaporizer. substantially without serious losses. 5. In an apparatus for recovering liquid oxygen Various changes may be made in the details of from atmospheric air, means for maintaining two the apparatus and the operation thereof with out departing from the linvention or sacrificing bodies of liquid oxygen at diiîerent levels, a con nection whereby the body at the lower level is the advantages thereof. 40 maintained under the static head of the liquid I claim: A purge 35 controlled by a valve 3B is con 1. The method of recovering liquid oxygen free from impurities by -separation from atmospheric air which comprises separating nitrogen from the oxygen of the air by liquefaction and rectifica tion, thereby producing a. ñrst body of liquid oxy gen, delivering liquid oxygen from the first body to a second body of liquid at a lower level under at the higher level, a condenser within the body at the higher level and means for delivering va por from the body at the lower level to the con 45 ' denser. WOLCOTT DENNIS.