US2095809A - Process for obtaining krypton and xenon from air - Google Patents

Process for obtaining krypton and xenon from air Download PDF

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Publication number
US2095809A
US2095809A US70967434A US2095809A US 2095809 A US2095809 A US 2095809A US 70967434 A US70967434 A US 70967434A US 2095809 A US2095809 A US 2095809A
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Prior art keywords
krypton
air
liquid
gas
oxygen
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English (en)
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Gomonet Eugene
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Airco Inc
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Air Reduction Co Inc
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
    • F25J3/04—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air
    • F25J3/04642—Recovering noble gases from air
    • F25J3/04745—Krypton and/or Xenon
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2205/00—Processes or apparatus using other separation and/or other processing means
    • F25J2205/30—Processes or apparatus using other separation and/or other processing means using a washing, e.g. "scrubbing" or bubble column for purification purposes
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2270/00—Refrigeration techniques used
    • F25J2270/04—Internal refrigeration with work-producing gas expansion loop
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2270/00—Refrigeration techniques used
    • F25J2270/40—Quasi-closed internal or closed external air refrigeration cycle
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S62/00—Refrigeration
    • Y10S62/923—Inert gas
    • Y10S62/925—Xenon or krypton

Definitions

  • the krypton and the xenon which are contained in very minute proportions in atmospheric air are, as known, less volatile. than all the other constituents of the air. They therefore collect in the oxygen when atmospheric air is treated by liquefaction and rectification in order to obtain its oxygen in a more or less pure state.
  • the quantities of krypton and xenon which can thus be obtained are very small and-cannot meet all the applications to which the peculiar properties of these gases may give rise, for instance the filling of gas-containing glowlamps.
  • krypton and xenon are directly extracted from atmospheric air without th latter having been subjected to a previous separation.
  • This process consists in directly subjecting atmospheric air, which has previously been cooled down to the neighbourhood of its dew point, to a rectification by a washing liquid consisting of a liquefied gas more volatile than krypton or by a mixture of such liquefied gases, the washing liquid being preferably utilized in a quantity large enough to allow the retention of substantially the whole of the krypton and the xenon, but nevertheless smallin proportion to the treated. air, and in concentrating in krypton and xenon the liquid resulting from the rectification by vaporizing nearly the whole of it. i
  • the washing liquid is preferably air which has formerly been freed from its krypton (for the sake of simplicity xenon will no longer be mentioned henceforth) butcit could also be nitrogen or oxygen or a mixture of these two substances in any proportions.
  • the quantity of the washing liquid may be less than the tenth part of the quantity of the treated air. If the Washing liquid contains no krypton the air may be completely free from krypton after its treatment.
  • the providing of the heat which is necessary for vaporizing the krypton-containing liquid preferably takes placein known manner by means of a substantially equivalent quantity of a cold gas which liquefies as the liquid vaporizes andis chosen of such a nature that the liquid resulting from its liquefaction may be used as a rectifying liquid for the treated air.
  • This cold gas may consist of a part of the air jected to the rectification.
  • tial proportion of constituents less volatile than oxygen may besubstantially pure oxygen.
  • the washing liquid instead of being obtained in a condenser-vaporizer by heat exchange of the krypton-containing liquid which has been used for rectifying the air with a corresponding quantity of a gas under the necessary pressure, could also be derived from the treated air itself.
  • the air may be circulated under the necessary pressure in a bundle of tubes for progressive liquefaction with backward return which is outwardly cooled by the vaporization, under a lower pressure, of the greater part of the liquid resulting from the backward return and to which the small quantity of the necessary make-up liquid has been added.
  • the krypton accumulates in the small nonvaporized part which is withdrawn from the backward return apparatus.
  • the air may be passed into a rectification column surmounted at its top by a condenser-vaporizer which is outwardly fed by the liquid which has been used for the rectification.
  • the process of this invention necessitates, at least for the air to be rectified, which constitutes by far the larger partof the treated gas, small pressure differences only.
  • the air may for instance be compressed to a pressure slightlyabove 50 he atmospheric and, after having been cooled, be th external work, preferably in a turbine, so as to provide all or part of the makeup liquid w ch is necessary for carrying out the process.
  • This liquid may also be formed in any liquid is vaporized by means of a substantially equal quantity of a cold gas, this gas may for instance consist of the expanded part of a gas subjected to the known cycle of liquefaction under pressure, whereas the non-expanded part provides the make-up liquid.
  • a cold gas is compressed with heat exchange between the gas to be compressed and the compressed gas, and then divided into two parts; one part is expanded with production of external work to a pressure which still allows of its liquefaction within a bath of the krypton-containing liquid to be vaporized, into which it is passed; the other part flows further in heat exchange with the cold gas to be compressed, and is liquefied by contact therewith, thus providing the make-up liquid.
  • the appended figure diagrammatically shows by way of example a manner for carrying out the process.
  • Air which has not previously been freed from its carbon dioxide is passed at the surrounding temperature, under a small pressure, for instance about 1,7 atm. absolute, alternately into the two cold regenerators Al and A2.
  • the figure shows the flow of the air to be treated through the regenerator Al.
  • the air When leaving this regenerator the air is at a temperature of about. l85 C. It is expanded with production of external work to about atmospheric pressure by passing through the turbine B. When leaving the turbine its temperature amounts to about minus 199 C.
  • the procedure is as follows: About one tenth of the krypton-free air which leaves the column C is compressed in the compressor E to about 15 atm. and the cold air to be compressed is successively passed through the exchangerliquefier G in counter-current to a part of the same air once compressed, then through the exchanger Fin counter-current to the whole of the compressed air; that part of the compressed air which does not fiow through the exchangerliquefier G is expanded in the expansion-machine H to a pressure between 2 and 3 atm.
  • the air could also be expanded after instead of before its rectification, immediately before entering the regenerator A2.
  • That small quantity of liquid which is not vaporized in the vaporizer D is discharged at the 'top of an auxiliary rectification column K at the bottom of which the larger part of the discharged liquid is vaporized by means of a heating coil attests L which is supplied with a portion of the cold compressed air which leaves the exchanger F.
  • the liquid formed in the coil L is united with that formed in the coil I.
  • the gas, containing some krypton, which leaves at the top of the column K is united, by means of the pipe M, with the gas which rises above the yaporizer D.
  • the liquid which is withdrawn in a small quantity at the bottom of the column K is rich in krypton. Krypton may be extracted therefrom in a.
  • a pipe P having a control valve Q connects the pipe M, through which the gas boiled from the liquid in the column K is conducted to the column C, with exchanger-liquefier G so thatoxygen-rich gas may be passed into the gaseous liquefaction system when it is desired to increase the oxygen content of the washing liquid introduced into the top of the column 0.
  • a suitable pump B. may be included in the pipe line P in order to force the oxygen-rich gas therethrough and into the exchanger-liquefier G.
  • a process of obtaining krypton the steps which comprise bringing air in a gaseous state into intimate contact with a liquefied gas more volatile than krypton to thereby wash krypton from said gaseous air and produce a liquid enriched in krypton, and removing nitrogen and the greater part of the oxygen of the gaseous air as waste gas.
  • a process of obtaining krypton and xenon the steps which comprise cooling gaseous air while maintaining it in a gaseous state, bringing said cooled gaseous air into intimate contact with a liquefiedgas more volatile than krypton to thereby wash krypton and xenon from said cooled gaseous air and produce a liquid enriched in krypton and xenon, and removing nitrogen and the greater part of the oxygen of the cooled gaseous air as waste gas.
  • a process of obtaining krypton the steps which comprise bringing air in a gaseous state into intimate contact with a liquefied gas more volatile than krypton to thereby wash krypton from said gaseous air and produce a liquid enriched in krypton, removing nitrogen and the greater part of the oxygen of the gaseous air as waste gas, and treating the obtained kryptonenriched liquid to increase the krypton content thereof.
  • the steps which comprise cooling gaseous air down to the neighborhood of its dew point, bringing said cooled gaseous air into intimate contact with a liquefied gas more volatile than krypton to thereby wash krypton from said gaseous air and produce a liquid enriched in krypton, removing nitrogen and the greater part of the oxygen of the cooled gaseous air, as waste gas, and treating the than krypton sufflcient to retain substantially the whole of the krypton contained in said gaseous air but insufiicient" to retain substantially the whole of the oxygen of said gaseous air, to produce a liquid enriched in krypton.
  • a process of obtaining krypton the steps which comprise cooling gaseous air while maintaining it in a gaseous state, washing said cooled gaseous air with a quantity of liquefied air sumcient to retain substantially the whole of the krypton contained in said cooled gaseous air but insufiicient to retain substantially the whole of the oxygen of said cooled gaseous air, to produce a liquid enriched in krypton, and treating the krypton-enriched liquid to increase the krypton content thereof.
  • a process of obtaining krypton and xenon the steps which comprise cooling atmospheric air down to the neighborhood of its dew po nt, washing said.cooled gaseous air with a liquid mixture of oxygen and nitrogen which is richer than atmospheric air in oxygen. to thereby produce a liquid enriched in krypton and xenon. vaporizing from said krypton-and-xenon-enriched liquid constituents thereof more volatile than krypton and xenon to thereby increase the krypton and xenon content thereof.
  • the steps which comprise cooling gaseous air down to the neighborhood of its dew point, washing said cooled gaseous air with a quantity of a nitrogen-containing liquefied gas sufficient to retain substantially the whole of the krypton of the cooled gaseousair but insumcient to retain substantially the whole 01' the oxygen of the cooled gaseous air, to produce a liquid enriched in krypton and xenon, and vaporizing nearly the whole of the liquid which was used for washing the cooled gaseous air.
  • a process of obtaining krypton the steps which comprise. bringing gaseous air into ,intimate contact with a liquefied gas more volatile than krypton to produce a liquid enriched in krypton, removing as waste gas nitrogen and the greater part of the oxygen of the treated gaseous air. vaporizing from said obtained krypton-enriched liquid constituents thereof more volatile than krypton, and uniting the vaporized constituents with the gaseous air to be treated.
  • a process of obtaining krypton the steps which comprise cooling gaseous air while maintaining it in a gaseous state, washing said cooled gaseous air with a liquefied gas more volatile than krypton to produce a krypton-enriched liquid, removing as waste gas nitrogen and the greater part of the oxygen of the treated gaseous 'air, and vaporizing nearly the whole of the liquid utilized for washing krypton from the treated air by heat exchange with substantially an equivalent quantity of a gas more volatile than krypton, which gas is thus liquefied and serves as a washing liquid for gaseous air to be treated.
  • the steps which comprise cooling gaseous air while maintaining it in a gaseous state, washing said cooled gaseous air with a quantity of a liquefied gas more volatile than krypton which is small in proportion to the amount of cooled gaseous air, compressing a cold gas more volatile than krypton with heat exchange of the cold gas to be compressed successively in a firststage with a part .of the same gas once compressed, whereby said part is liqucfied, and in a second stage with the whole of said gas once compressed, partially expanding that part of the gas once compressed which is not subjected to the first stage heat exchange, liquefying said partially expanded part of the gas by heat exchange with the liquid utilized for the washing of the treated air, whereby said liquid is nearly entirely vaporized, expanding the two liq- .uids resulting from'said liquefaction of the porzation by the liquid to be vaporized, and withdrawinga part of the gas undergoing
  • aprocess of obtaining krypton the steps which comprise passing gaseous air and a liquefied gas more volatile than krypton in opposite directions through a chamber, discharging nitrogen mixed with the greater part of the oxygen from said chamber, collecting krypton-enriched liquid within said chamber, and treating said krypton-enriched liquid to content thereof.
  • the steps which comprise bringing gaseous air intointimate contact with a washing liquid at a temperature lower than the temperature of liquid oxygen at the pressure under which the washing operation increase the krypton .is conducted, to produce a krypton-enriched. liquid, removingas waste gas. nitrogen mixed with the greater part of the oxygen of the gaseous air, and treating the obtained krypton-enriched liquidto increase the krypton content thereof.
  • a process of obtaining krypton the steps which comprise cooling gaseous air while maintaining it in a gaseous state, bringing said cooled gaseous air into intimate contact with a washing liquid at a temperature lower than the temperature oi liquid oxygen at the pressure under which the washing operation is conducted, to produce a krypton-enriched liquid, removing, as waste gas, nitrogen mixed with the greater part of the oxygen of the cooled gaseous air, utilizing said waste gas, before being finally discharged, to cool incoming gaseous air, and treating the obtained krypton-enriched liquid to increase the krypton content thereof.
  • a process of obtaining krypton the steps which comprise bringing gaseous air into intimate contact with a liquefied gas more volatile than krypton at a temperature lower than the tem- 4 perature of liquid oxygen at the pressure under which the washing operation is conducted, to produce a liquid enriched in krypton, a part of said washing liquid being obtained by cooling a preincoming gaseous air, and treating the obtained 7 krypton-enriched liquid fraction to increase thekrypton content thereof.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Separation By Low-Temperature Treatments (AREA)
US70967434 1933-02-09 1934-02-03 Process for obtaining krypton and xenon from air Expired - Lifetime US2095809A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DEA68603A DE628788C (de) 1933-02-09 1933-02-09 Herstellung von Krypton und Xenon

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US2095809A true US2095809A (en) 1937-10-12

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US12913937 Expired - Lifetime US2101300A (en) 1933-02-09 1937-03-05 Process for the manufacture of krypton and xenon by separation from atmospheric air

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US (2) US2095809A (enrdf_load_stackoverflow)
AT (1) AT148690B (enrdf_load_stackoverflow)
BE (1) BE401006A (enrdf_load_stackoverflow)
DE (1) DE628788C (enrdf_load_stackoverflow)
DK (1) DK50939C (enrdf_load_stackoverflow)
FR (2) FR768197A (enrdf_load_stackoverflow)
GB (1) GB432644A (enrdf_load_stackoverflow)
NL (1) NL46810C (enrdf_load_stackoverflow)
SE (1) SE89690C1 (enrdf_load_stackoverflow)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2608070A (en) * 1944-02-11 1952-08-26 Kapitza Peter Leonidovitch Method and means for distillation of low boiling point liquids
US2619813A (en) * 1947-05-14 1952-12-02 British Oxygen Co Ltd Separation of gas mixtures
US2627731A (en) * 1949-06-18 1953-02-10 Hydrocarbon Research Inc Rectification of gaseous mixtures
US2731810A (en) * 1949-01-04 1956-01-24 Qjivaiiov snoonilnod
US2765637A (en) * 1950-10-30 1956-10-09 Air Liquide Frigorific separation process of gas mixture by liquefying and rectifying
US2771751A (en) * 1953-07-24 1956-11-27 Hartford Nat Bank & Trust Co Gas-fractionating installation
US2793511A (en) * 1953-04-29 1957-05-28 Air Liquide Method for obtaining krypton and xenon
US2808709A (en) * 1952-01-12 1957-10-08 Philips Corp Method of separating gas mixtures into fractions of different volatility
US2960838A (en) * 1956-06-19 1960-11-22 Atomic Energy Authority Uk Hydrogen distillation plant
US3222878A (en) * 1962-12-21 1965-12-14 Linde Eismasch Ag Method and apparatus for fractionation of air
US3258930A (en) * 1961-02-23 1966-07-05 Linde Eismasch Ag Process and apparatus for separating gaseous mixtures by low-temperature rectification

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR980658A (fr) * 1948-02-12 1951-05-16 British Oxygen Co Ltd Procédé de séparation fractionnée de l'air
US2664719A (en) * 1950-07-05 1954-01-05 Union Carbide & Carbon Corp Process and apparatus for separating gas mixtures
NL196122A (enrdf_load_stackoverflow) * 1951-11-30 1900-01-01
US3191393A (en) * 1959-12-30 1965-06-29 Air Reduction Krypton-xenon separation from a gas mixture
US4401448A (en) * 1982-05-24 1983-08-30 Union Carbide Corporation Air separation process for the production of krypton and xenon
CN108031138A (zh) * 2017-12-14 2018-05-15 浙江新锐空分设备有限公司 一种氪氙浓缩塔底部蒸发热源系统

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2608070A (en) * 1944-02-11 1952-08-26 Kapitza Peter Leonidovitch Method and means for distillation of low boiling point liquids
US2619813A (en) * 1947-05-14 1952-12-02 British Oxygen Co Ltd Separation of gas mixtures
US2731810A (en) * 1949-01-04 1956-01-24 Qjivaiiov snoonilnod
US2627731A (en) * 1949-06-18 1953-02-10 Hydrocarbon Research Inc Rectification of gaseous mixtures
US2765637A (en) * 1950-10-30 1956-10-09 Air Liquide Frigorific separation process of gas mixture by liquefying and rectifying
US2808709A (en) * 1952-01-12 1957-10-08 Philips Corp Method of separating gas mixtures into fractions of different volatility
US2793511A (en) * 1953-04-29 1957-05-28 Air Liquide Method for obtaining krypton and xenon
US2771751A (en) * 1953-07-24 1956-11-27 Hartford Nat Bank & Trust Co Gas-fractionating installation
US2960838A (en) * 1956-06-19 1960-11-22 Atomic Energy Authority Uk Hydrogen distillation plant
US3258930A (en) * 1961-02-23 1966-07-05 Linde Eismasch Ag Process and apparatus for separating gaseous mixtures by low-temperature rectification
US3222878A (en) * 1962-12-21 1965-12-14 Linde Eismasch Ag Method and apparatus for fractionation of air

Also Published As

Publication number Publication date
DK50939C (da) 1935-11-25
AT148690B (de) 1937-02-25
SE89690C1 (enrdf_load_stackoverflow) 1937-07-13
GB432644A (en) 1935-07-31
FR768197A (fr) 1934-08-01
NL46810C (enrdf_load_stackoverflow) 1939-10-10
FR47423E (fr) 1937-05-05
BE401006A (enrdf_load_stackoverflow) 1934-02-28
US2101300A (en) 1937-12-07
DE628788C (de) 1936-04-16

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