EP0636237B1 - Process for the low-temperature air separation and air separation plant - Google Patents

Process for the low-temperature air separation and air separation plant Download PDF

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Publication number
EP0636237B1
EP0636237B1 EP93920521A EP93920521A EP0636237B1 EP 0636237 B1 EP0636237 B1 EP 0636237B1 EP 93920521 A EP93920521 A EP 93920521A EP 93920521 A EP93920521 A EP 93920521A EP 0636237 B1 EP0636237 B1 EP 0636237B1
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EP
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Prior art keywords
column
pressure column
low
packing
specific surface
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Revoked
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EP93920521A
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German (de)
French (fr)
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EP0636237A1 (en
Inventor
Wilhelm Rohde
Anton Moll
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Linde GmbH
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Linde GmbH
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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
    • F25J3/04763—Start-up or control of the process; Details of the apparatus used
    • F25J3/04866—Construction and layout of air fractionation equipments, e.g. valves, machines
    • F25J3/04896—Details of columns, e.g. internals, inlet/outlet devices
    • F25J3/04909—Structured packings
    • 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
    • F25J3/04248—Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion
    • F25J3/04284—Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion using internal refrigeration by open-loop gas work expansion, e.g. of intermediate or oxygen enriched (waste-)streams
    • F25J3/0429—Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion using internal refrigeration by open-loop gas work expansion, e.g. of intermediate or oxygen enriched (waste-)streams of feed air, e.g. used as waste or product air or expanded into an auxiliary column
    • F25J3/04303—Lachmann expansion, i.e. expanded into oxygen producing or low pressure column
    • 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
    • F25J3/04406—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 using a dual pressure main column system
    • F25J3/04412—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 using a dual pressure main column system in a classical double column flowsheet, i.e. with thermal coupling by a main reboiler-condenser in the bottom of low pressure respectively top of high pressure column
    • 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
    • F25J3/04648—Recovering noble gases from air argon
    • F25J3/04654—Producing crude argon in a crude argon column
    • F25J3/04666—Producing crude argon in a crude argon column as a parallel working rectification column of the low pressure column in a dual pressure main column system
    • F25J3/04672—Producing crude argon in a crude argon column as a parallel working rectification column of the low pressure column in a dual pressure main column system having a top condenser
    • F25J3/04678—Producing crude argon in a crude argon column as a parallel working rectification column of the low pressure column in a dual pressure main column system having a top condenser cooled by oxygen enriched liquid from high pressure column bottoms
    • 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
    • F25J3/04763—Start-up or control of the process; Details of the apparatus used
    • F25J3/04866—Construction and layout of air fractionation equipments, e.g. valves, machines
    • F25J3/04896—Details of columns, e.g. internals, inlet/outlet devices
    • F25J3/04915—Combinations of different material exchange elements, e.g. within different columns
    • F25J3/04921—Combinations of different material exchange elements, e.g. within different columns within the same column
    • 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
    • F25J2200/00—Processes or apparatus using separation by rectification
    • F25J2200/20—Processes or apparatus using separation by rectification in an elevated pressure multiple column system wherein the lowest pressure column is at a pressure well above the minimum pressure needed to overcome pressure drop to reject the products to atmosphere
    • 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
    • F25J2235/00—Processes or apparatus involving steps for increasing the pressure or for conveying of liquid process streams
    • F25J2235/58—Processes or apparatus involving steps for increasing the pressure or for conveying of liquid process streams the fluid being argon or crude argon
    • 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
    • Y10S62/902—Apparatus
    • Y10S62/905—Column
    • Y10S62/906—Packing
    • 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
    • Y10S62/924—Argon

Definitions

  • the invention relates to a process for the low-temperature decomposition of air, in which purified and cooled air is passed into a distillation system having at least one rectification column and is rectified there by countercurrent mass transfer between a vapor and a liquid phase, the mass transfer in at least one partial area of at least one rectification column is caused by a pack.
  • packing includes both ordered packings and unordered packings (packed beds).
  • EP-A-0 321 163 it is known from EP-A-0 321 163 to use a packing at least in a partial area of the low pressure column of a two-stage air separator. It is proposed to use packs known from other areas of distillation, since it is said that the special properties of the pack are not important. Such, for example ordered, packs usually have a specific surface area (ie the surface available for mass transfer relative to the total volume of the pack) of 125 to 700 m 2 / m 3 . The use of higher density packs in industrial air separators is not yet known.
  • EP-A-0 467 395 in which a blanket range between 250 and 1000 m 2 / m 3 is cited, is limited in its concrete design to specific surfaces up to a maximum of 700 m 2 / m 3 .
  • the present invention is therefore based on the object of specifying a method and a device of the type mentioned at the outset which are economically particularly favorable, in particular due to relatively low installation costs.
  • This object is achieved in that the mass transfer in at least a partial area of at least one rectification column is effected by a packing which has a specific surface area of more than 1000 m 2 / m 3 .
  • the dense packing otherwise preferably has an ordered structure, similar to, for example, packings known from DE-C-27 22 424 or DE-B-27 22 556.
  • a smooth packing is preferably used, the structure of which is described in WO-A-9319335, to which reference is expressly made here.
  • the mass transfer in the top and / or in the bottom section of the rectification column is at least partially effected by a packing which has a specific surface area of more than 1000 m 2 / m 3 .
  • the uppermost column section can be, for example, the pure nitrogen section of an air separation column, through which only a part of the nitrogen product is passed, and the lowest section around the oxygen section, which generally also has a relatively low throughput of gas and has liquid.
  • the packing which is particularly dense in terms of the mass transfer area, can fully develop its advantages.
  • the rectification column in which mass transfer in at least one partial area is at least partially effected by a packing which has a specific surface area of more than 1000 m 2 / m 3 , is preferably a low-pressure column, as occurs, for example, in a double-column process.
  • a low-pressure column as occurs, for example, in a double-column process.
  • large partial areas or also the entire area of the low-pressure column that is effective for mass transfer can be equipped with a tight packing.
  • a crude argon column is connected to a low-pressure column.
  • this is the low-pressure column of a two-stage column, but in principle it is also possible to connect a crude argon column to a single column for nitrogen-oxygen separation.
  • a package with more than 1000 m 2 / m 3 can be used both in the crude argon column and in the low pressure column or only in one of the two columns, for example in the low pressure column.
  • the mass transfer is effected at least in a partial area of the crude argon column by a packing which has a specific surface area of at least 1000 m 2 / m 3 .
  • a large part, essentially all or all of the mass transfer in the crude argon column can be brought about by such a packing.
  • Another aspect of the invention relates to a process for the low-temperature separation of air, in which purified and cooled air is passed into a distillation system which has at least two rectification columns, including a low-pressure column and a crude argon column, and there by countercurrent mass transfer between each Vapor and a liquid phase is rectified, whereby in the process an argon-containing oxygen stream is removed from the low pressure column and broken down into crude argon and into a residual fraction in the crude argon column and the mass transfer is effected in at least a portion of the crude argon column by an orderly packing.
  • the above-described object is achieved in that the mass transfer is effected at least in a partial area of the crude argon column by an orderly packing which has a specific surface area of at least 1000 m 2 / m 3 .
  • the mass transfer is preferably effected at least in a partial area of the rectification column or the crude argon column by an ordered packing which has a specific surface area of at least 1100 m 2 / m 3 .
  • the invention is also advantageous to apply the invention to a double-column process in which the distillation system has a pressure column and a low-pressure column, at least some of the cleaned and cooled air being introduced into the pressure column and an oxygen-enriched and a nitrogen-rich fraction from the pressure column in the low pressure column are introduced.
  • This double column can, for example, serve exclusively for the production of oxygen and / or nitrogen, or additional separation columns can be connected for the production of noble gases.
  • the height reduced by the invention has a particularly great advantage.
  • pumps otherwise required for conveying the liquid fractions from the pressure column to the low pressure column can be dispensed with. This is especially true when the head of the low pressure column is cooled by indirect heat exchange with a fraction from the lower area of the pressure column.
  • the mass transfer in the section of the low-pressure column which lies below the point where the oxygen-enriched fraction from the pressure column is fed in, is at least partially effected by a pack which has a specific Has surface area of more than 1000 m 2 / m 3 .
  • This section is commonly referred to as the oxygen section. Since the feeds of the two fractions from the pressure column lie above this section, this section has a relatively low load.
  • the pure nitrogen section which lies between the head of the low-pressure column, from which a pure nitrogen fraction is removed, and the removal point of an impure nitrogen fraction below the head, and to the intermediate argon section.
  • the latter is located between the point of withdrawal of an argon-containing oxygen stream which is led to the crude argon column and the feed point of a fraction evaporated from the top of the crude argon column in indirect heat exchange with gas.
  • the mass transfer is preferably effected at least partially by a packing which has a specific surface area of more than 1000 m 2 / m 3 .
  • the mass exchange in the pressure column can also be effected at least partially by a packing. It can be a pack with a high specific surface area, but also the use of a less dense one Packing is possible. The use of a very dense packing is only rarely used in the pressure column.
  • the invention also relates to an air separation plant according to claims 15 and 21.
  • Claims 16 to 20 and 22 to 28 relate to special embodiments of these air separation plants according to the invention.
  • cleaned air 1 is cooled under a pressure of 4 to 20 bar, preferably 5 to 12 bar, in a heat exchanger 2 against product flows to approximately dew point and fed into the pressure column 3 of a two-stage rectification device.
  • the pressure column 3 is in heat exchange relationship with a low-pressure column 5 via a common condenser-evaporator 4.
  • FIG. 3 shows a crude argon column 15 connected to the air rectification.
  • An argon-containing oxygen stream is taken from the lower region of the low-pressure column 5 (below the bottom liquid line 6) via argon transfer line 14, passed into the lower region of the crude argon column 15 and there into a crude argon product 16 and a residual fraction 17 disassembled. The remaining fraction is returned to the low pressure column. It can either flow back via line 14 (if a corresponding gradient is present) or, as shown in FIG. 3, can be conveyed by means of a pump 18 via its own line 17.
  • the head of the crude argon column is cooled by a crude argon condenser 19, on the evaporation side of which sump liquid which is brought in via line 20 evaporates from the pressure column 3.
  • the evaporated fraction is fed via line 21 to the low pressure column. It can be introduced, for example, at the level of the sump liquid line 6. However, a feed between the mouth of the sump liquid line 6 and the connection of the argon transfer line is particularly advantageous.
  • FIG. 4 shows a combination of the variants in FIGS. 2 and 3.
  • relaxed air is blown directly into the low-pressure column 5 in a turbine 12. Similar to the method in FIG. 2, it is possible to introduce the turbine air, for example, at the level of the bottom liquid line 6. It is preferably, as shown in FIG. 4, fed in from the crude argon condenser 19 in the region between the bottom liquid inlet 6 and the introduction of the vaporized fraction 21. So the impure oxygen section is further divided into two subsections C 1 and C 2 .
  • the mass transfer in some sections of the low-pressure column 5 is at least partially effected by a packing which has a specific surface area of more than 1000 m 2 / m 3
  • / or the mass transfer in the crude argon column 15 is at least partially effected by a packing which has a specific surface area of at least 1000 m 2 / m 3 .
  • Packs do not have to be used in every section of the low-pressure column to implement the invention; in one or more sections, the mass transfer can also be effected partially or exclusively by other mass transfer elements, for example by conventional rectification trays such as bubble-cap trays or sieve trays. In a section in which a packing is arranged in one or more sub-areas, the mass transfer in other sub-areas can be brought about by other mass transfer elements.
  • packs are mainly used in all sections of the low-pressure column 5 in order to effect the mass transfer.
  • a simple form of realizing the invention is a method according to FIG. 1, in which in a nitrogen section, for example in the oxygen section E and / or in the pure nitrogen section, a packing with a specific surface area of more than 1000 m 2 / m 3 is used.
  • the following table shows a numerical example for a low-pressure column with five sections according to FIG. 3.
  • the designation of the sections in the exemplary embodiments of the other figures is chosen so that the values in the table can be transferred directly to these variants.
  • the table contains a range of numbers for the load (throughput of rising gas) relative to the impure nitrogen section B, a preferred range of numbers for a pack to be used in the section and two particularly preferred numerical values of specific exemplary embodiments.
  • TABLE section relative load% specific surface area m 2 / m 3 A Pure nitrogen section 60-75 600-1250 750 1100 B Impure nitrogen section 100 350-800 500 750 C. Impure oxygen section about 90 350-800 500 750 D Argon intermediate section 40-50 600-1500 1100 1250 E Oxygen section 75-85 500-1250 750 1100
  • section B which is most heavily loaded, a relatively coarse packing is used.
  • Sections with a lower load, for example section E, are preferably provided with finer packs.
  • the intermediate argon section D preferably contains a pack with a particularly high specific surface area.
  • the value of 1500 m 2 / m 3 is not an upper limit, in principle higher specific surfaces are also conceivable.
  • the packs used in different sections can otherwise have the same or different structure. However, it is preferred to use packs arranged in one, several or all sections, as described in WO-A-9319335 with the same priority. Different specific surfaces are created by different amplitudes in the folding of the slats from which the package is made.
  • the overall height of the low-pressure column 5 of the exemplary embodiments is significantly lower than, for example, when packs with a specific surface area of less than 1000 m 2 / m 3 are used exclusively.
  • the mass transfer in one or more partial areas or in the entire column can also be effected by packing in the pressure column 3 and / or in particular in the crude argon column 15. These preferably also have the structure described in WO-A-9319335.
  • Packs of different specific surface areas can also be used in the crude argon column, but a pack with a constant specific surface area is preferably used.
  • the particularly preferred values of the specific surface area of this packing are 1000 to 1500 m 2 / m 3 , preferably 1100 to 1250 m 2 / m 3 .
  • the packing density in the crude argon column can also be below this limit, preferably 700 to 900 m 2 / m 3 , in particular at approx. 750 m 2 / m 3 .
  • a particularly dense packing is also particularly favorable in air separation plants and processes in which a rectification column is installed in a vacuum container, for example a liquid tank.
  • a vacuum container for example a liquid tank.
  • the application of the invention to methods and devices in which liquid oxygen is evaporated against a condensing fraction is also advantageous.
  • the oxygen product is often brought under pressure in liquid form (so-called internal compression), for example by using a hydrostatic potential or by a pump. If air condensed against evaporating oxygen is fed into a central point of the pressure column, it may be expedient to use packings of different densities in the pressure column above and below this feed point.

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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)
  • Vaporization, Distillation, Condensation, Sublimation, And Cold Traps (AREA)

Abstract

In the process for low-temperature air separation, cleaned and cooled air is taken into a distilling system having at least one rectifier column and rectified there by counterflow material exchange between a vapour and a liquid phase. The substance exchange in at least one partial region of at least one rectifier column (3, 5, 15) is effected by a packing with a specific area of at least 1000 m2/m3.

Description

Die Erfindung betrifft ein Verfahren zur Tieftemperaturzerlegung von Luft, bei dem gereinigte und abgekühlte Luft in ein mindestens eine Rektifiziersäule aufweisendes Destilliersystem geleitet und dort durch Gegenstrom-Stoffaustausch zwischen einer Dampf- und einer Flüssigkeitsphase rektifiziert wird, wobei der Stoffaustausch in mindestens einem Teilbereich mindestens einer Rektifiziersäule durch eine Packung bewirkt wird.The invention relates to a process for the low-temperature decomposition of air, in which purified and cooled air is passed into a distillation system having at least one rectification column and is rectified there by countercurrent mass transfer between a vapor and a liquid phase, the mass transfer in at least one partial area of at least one rectification column is caused by a pack.

Seit einiger Zeit hat man begonnen, in der Tieftemperaturtechnik, insbesondere bei der Luftzerlegung Packungen einzusetzen, die bisher hauptsächlich für andere Trennaufgaben verwendet wurden. Der Begriff Packung schließt hier sowohl geordnete Packungen als auch ungeordnete Packungen (Füllkörperschüttungen) ein.For some time now, low temperature technology, especially air separation, has started to use packings that were previously mainly used for other separation tasks. The term packing here includes both ordered packings and unordered packings (packed beds).

Beispielsweise aus der EP-A-0 321 163 ist bekannt, mindestens in einem Teilbereich der Niederdrucksäule eines zweistufigen Luftzerlegers eine Packung einzusetzen. Dabei wird vorgeschlagen, aus anderen Gebieten der Destillation bekannte Packungen zu verwenden, da es angeblich nicht auf die speziellen Eigenschaften der Packung ankommt. Üblicherweise besitzen derartige, beispielsweise geordneten, Packungen eine spezifische Oberfläche (d.h. für den Stoffaustausch zur Verfügung stehende Oberfläche relativ zum Gesamtvolumen der Packung) von 125 bis 700 m2/m3. Der Einsatz von Packungen höherer Dichte in industriellen Luftzerlegern ist bisher nicht bekannt. Auch die EP-A-0 467 395, in der pauschal ein Bereich zwischen 250 und 1000 m2/m3 genannt ist, beschränkt sich in der konkreten Ausführung auf spezifische Oberflächen bis höchstens 700 m2/m3.For example, it is known from EP-A-0 321 163 to use a packing at least in a partial area of the low pressure column of a two-stage air separator. It is proposed to use packs known from other areas of distillation, since it is said that the special properties of the pack are not important. Such, for example ordered, packs usually have a specific surface area (ie the surface available for mass transfer relative to the total volume of the pack) of 125 to 700 m 2 / m 3 . The use of higher density packs in industrial air separators is not yet known. EP-A-0 467 395, in which a blanket range between 250 and 1000 m 2 / m 3 is cited, is limited in its concrete design to specific surfaces up to a maximum of 700 m 2 / m 3 .

Durch den gegenüber ausschließlich mit konventionellen Rektifizierböden ausgestatteten Kolonnen verringerten Druckabfall kann das Verfahren bei gleichen Produktspezifikationen mit geringerem Einsatzdruck gefahren werden, Dem dadurch bewirkten Rückgang an Energiekosten stehen jedoch erhöhte Kosten für die Herstellung der Rektifiziersäule gegenüber.Due to the reduced pressure drop compared to columns equipped exclusively with conventional rectification trays, the process can be carried out with the same product specifications with a lower operating pressure. However, the resulting reduction in energy costs is offset by increased costs for the production of the rectification column.

Der vorliegenden Erfindung liegt daher die Aufgabe zugrunde, ein Verfahren und eine Vorrichtung der eingangs genannten Art anzugeben, die wirtschaftlich besonders günstig sind, insbesondere durch relativ geringe Anlagekosten.The present invention is therefore based on the object of specifying a method and a device of the type mentioned at the outset which are economically particularly favorable, in particular due to relatively low installation costs.

Diese Aufgabe wird dadurch gelöst, daß der Stoffaustausch in mindestens einem Teilbereich mindestens einer Rektifiziersäule durch eine Packung bewirkt wird, die eine spezifische Oberfläche von mehr als 1000 m2/m3 aufweist.This object is achieved in that the mass transfer in at least a partial area of at least one rectification column is effected by a packing which has a specific surface area of more than 1000 m 2 / m 3 .

Durch Einspeisungen und Abführungen von verschiedenen Fraktionen weisen verschiedene Abschnitte einer Luftzerlegersäule in der Regel verschiedene Belastungen, das heißt unterschiedliche Durchsätze an Dampf und Flüssigkeit auf. Wenn insbesondere in relativ gering belasteten Teilbereichen einer Rektifiziersäule eines Luftzerlegungsverfahrens eine Packung eingesetzt wird, hat es sich im Rahmen der Erfindung gezeigt, daß durch den Einsatz einer Packung mit sehr hoher spezifischer Oberfläche die Höhe der entsprechenden mit Packungen gefüllten Säulenbereiche erheblich geringer ist. Im Vergleich zu den aus dem Stand der Technik bekannten Verfahren ergeben sich bei gleicher Stoffaustauschwirkung eine geringere Gesamthöhe der Säule und die damit verbunden entsprechend niedrige Anlagekosten. Dies gilt selbstverständlich in verstärktem Maße bei einer Rektifiziersäule, bei der in allen gepackten Abschnitten Packungen von mehr als 1000 m2/m3 eingesetzt werden.Due to the feeding and discharge of different fractions, different sections of an air separation column generally have different loads, that is to say different throughputs of steam and liquid. If a packing is used in particular in relatively lightly loaded partial areas of a rectification column of an air separation process, it has been shown in the context of the invention that by using a packing with a very high specific surface, the height of the corresponding pillar areas filled with packing is considerably lower. In comparison to the methods known from the prior art, the total mass of the column is lower and the correspondingly low investment costs are associated with the same mass transfer effect. Of course, this applies to an even greater extent in the case of a rectification column in which packs of more than 1000 m 2 / m 3 are used in all packed sections.

Aus früheren Messungen im Bereich von spezifischen Oberflächen bis etwa 500 m2/m3 war jedoch zu erwarten, daß sich die hydraulischen Eigenschaften einer sehr dichten Packung deutlich verschlechtern, daß insbesondere der Druckverlust pro theoretischem Boden mit steigender Packungsdichte merklich anwächst und auch der für eine bestimmte Gasbelastung benötigte Kolonnendurchmesser ansteigt. In der begründeten Erwartung, daß sich dieser Zusammenhang bei höheren absoluten spezifischen Oberflächen fortsetzen würde, kamen solche dichteren Packungen wegen der vorauszusehenden wirtschaftlichen Nachteile beim Einsatz in industriellen Luftzerlegern nicht in Frage. Darüber hinaus war außerdem mit größeren Problemen bei der Verteilung von Gas und insbesondere von Flüssigkeit auf die Packung sowie bei der Querverteilung von Gas und Flüssigkeit innerhalb der Packung zu rechnen.From previous measurements in the range of specific surfaces up to about 500 m 2 / m 3 , however, it was to be expected that the hydraulic properties of a very dense packing would deteriorate significantly, that in particular the pressure loss per theoretical floor would increase noticeably with increasing packing density and also for one certain gas load required column diameter increases. In the reasonable expectation that this relationship would continue at higher absolute specific surfaces, such denser packings were out of the question because of the foreseeable economic disadvantages when used in industrial air separators. In addition, major problems with the distribution of gas and, in particular, liquid onto the package and with the transverse distribution of gas and liquid within the package were also to be expected.

Im Rahmen umfangreicher Messungen, die in einer aufwendigen Versuchsanlage unter den Bedingungen eines industriellen Luftzerlegers durchgeführt wurden, hat sich herausgestellt, daß im Falle der Rektifikation von Luftgasen die hydraulischen Verschlechterungen bei Packungen mit spezifischer Oberfläche oberhalb etwa 1000 m2/m3 sehr viel geringer ausfallen, als nach bisherigen Erkenntnissen zu erwarten war. Dieser Effekt ist so bedeutend, daß beim Einsatz derart dichter Packungen bei der Luftrektifikation die Vorteile hinsichtlich der Anlagekosten die Nachteile in der Hydraulik deutlich überwiegen. Dies gilt insbesondere beim Einsatz dieser Art von Packungen in relativ gering belasteten Abschnitten einer Säule oder in einer Säule mit konstanter Gasbelastung.In the context of extensive measurements, which were carried out in a complex test facility under the conditions of an industrial air separator, it was found that in the case of rectification of air gases, the hydraulic deterioration in packs with a specific surface area above about 1000 m 2 / m 3 was much less than was to be expected based on previous knowledge. This effect is so significant that when using such dense packs for air rectification, the advantages in terms of system costs Disadvantages in hydraulics clearly outweigh them. This applies in particular when using this type of packing in relatively lightly loaded sections of a column or in a column with a constant gas load.

Die dichte Packung weist ansonsten vorzugsweise geordnete Struktur auf, ähnlich wie beispielsweise aus DE-C-27 22 424 oder DE-B-27 22 556 bekannte Packungen. Bevorzugt wird jedoch eine glatte Packung eingesetzt, deren Struktur in der WO-A-9319335 beschrieben ist, auf die hier ausdrücklich Bezug genommen wird.The dense packing otherwise preferably has an ordered structure, similar to, for example, packings known from DE-C-27 22 424 or DE-B-27 22 556. However, a smooth packing is preferably used, the structure of which is described in WO-A-9319335, to which reference is expressly made here.

In vorteilhafter Weiterbildung des Erfindungsgedankens wird der Stoffaustausch im obersten und/oder im untersten Abschnitt der Rektifiziersäule mindestens teilweise durch eine Packung bewirkt wird, die eine spezifische Oberfläche von mehr als 1000 m2/m3 aufweist. Bei dem obersten Säulenabschnitt kann es sich beispielsweise um den Rein-Stickstoff-Abschnitt einer Luftzerlegersäule handelt, durch den nur ein Teil des Stickstoffprodukts geführt wird, bei dem untersten Abschnitt um den Sauerstoff-Abschnitt, der in der Regel ebenfalls einen relativ geringen Durchsatz an Gas und Flüssigkeit aufweist. An diesen Stellen kann die von der Stoffaustauschfläche her besonders dichte Packung ihre Vorteile voll entfalten.In an advantageous development of the inventive concept, the mass transfer in the top and / or in the bottom section of the rectification column is at least partially effected by a packing which has a specific surface area of more than 1000 m 2 / m 3 . The uppermost column section can be, for example, the pure nitrogen section of an air separation column, through which only a part of the nitrogen product is passed, and the lowest section around the oxygen section, which generally also has a relatively low throughput of gas and has liquid. At these points, the packing, which is particularly dense in terms of the mass transfer area, can fully develop its advantages.

Bei der Rektifiziersäule, in der Stoffaustausch in mindestens einem Teilbereich mindestens teilweise durch eine Packung bewirkt wird, die eine spezifische Oberfläche von mehr als 1000 m2/m3 aufweist, handelt es sich vorzugsweise um eine Niederdrucksäule, wie sie beispielsweise bei einem Doppelsäulenverfahren vorkommt. Insbesondere können weite Teilbereiche oder auch der gesamte für den Stoffaustausch wirksame Bereich der Niederdrucksäule mit einer dichten Packung ausgestattet sein.The rectification column, in which mass transfer in at least one partial area is at least partially effected by a packing which has a specific surface area of more than 1000 m 2 / m 3 , is preferably a low-pressure column, as occurs, for example, in a double-column process. In particular, large partial areas or also the entire area of the low-pressure column that is effective for mass transfer can be equipped with a tight packing.

Die Vorteile des erfindungsgemäßen Verfahrens kommen im Falle des Anschlusses einer Rohargonsäule an eine Niederdrucksäule noch stärker zur Geltung. In der Regel handelt es sich dabei um die Niederdrucksäule einer zweistufigen Säule, grundsätzlich ist jedoch auch der Anschluß einer Rohargonsäule an eine Einzelsäule zur Stickstoff-Sauerstoff-Trennung möglich. Gemäß der Erfindung kann sowohl in der Rohargonsäule als auch in der Niederdrucksäule oder lediglich in einer der beiden Säulen, beispielsweise in der Niederdrucksäule, eine Packung mit mehr als 1000 m2/m3 eingesetzt werden.The advantages of the method according to the invention come to the fore even more when a crude argon column is connected to a low-pressure column. As a rule, this is the low-pressure column of a two-stage column, but in principle it is also possible to connect a crude argon column to a single column for nitrogen-oxygen separation. According to the invention, a package with more than 1000 m 2 / m 3 can be used both in the crude argon column and in the low pressure column or only in one of the two columns, for example in the low pressure column.

Besonders günstig ist es, wenn der Stoffaustausch mindestens in einem Teilbereich der Rohargonsäule durch eine Packung bewirkt wird, die eine spezifische Oberfläche von mindestens 1000 m2/m3 aufweist. In vielen Fällen kann ein großer Teil, im wesentlichen der gesamte oder auch der gesamte Stoffaustausch in der Rohargonsäule durch eine derartige Packung bewirkt werden.It is particularly favorable if the mass transfer is effected at least in a partial area of the crude argon column by a packing which has a specific surface area of at least 1000 m 2 / m 3 . In many cases, a large part, essentially all or all of the mass transfer in the crude argon column can be brought about by such a packing.

Ein weiterer Aspekt der Erfindung bezieht sich auf ein Verfahren zur Tieftemperaturzerlegung von Luft, bei dem gereinigte und abgekühlte Luft in ein Destilliersystem geleitet wird, das mindestens zwei Rektifiziersäulen, darunter eine Niederdrucksäule und eine Rohargonsäule, aufweist, und dort durch Gegenstrom-Stoffaustausch zwischen jeweils einer Dampf- und einer Flüssigkeitsphase rektifiziert wird, wobei bei dem Verfahren ein argonhaltiger Sauerstoffstrom aus der Niederdrucksäule entnommen und in der Rohargonsäule in Rohargon und in eine Rest fraktion zerlegt wird und der Stoffaustausch in mindestens einem Teilbereich der Rohargonsäule durch eine geordnete Packung bewirkt wird. Hierbei wird die oben beschriebene Aufgabe dadurch gelöst, daß der Stoffaustausch mindestens in einem Teilbereich der Rohargonsäule durch eine geordnete Packung bewirkt wird, die eine spezifische Oberfläche von mindestens 1000 m2/m3 aufweist.Another aspect of the invention relates to a process for the low-temperature separation of air, in which purified and cooled air is passed into a distillation system which has at least two rectification columns, including a low-pressure column and a crude argon column, and there by countercurrent mass transfer between each Vapor and a liquid phase is rectified, whereby in the process an argon-containing oxygen stream is removed from the low pressure column and broken down into crude argon and into a residual fraction in the crude argon column and the mass transfer is effected in at least a portion of the crude argon column by an orderly packing. Here, the above-described object is achieved in that the mass transfer is effected at least in a partial area of the crude argon column by an orderly packing which has a specific surface area of at least 1000 m 2 / m 3 .

Als Beispiel sei hier auf ein Verfahren zur rein rektifikatorischen Abtrennung von Sauerstoff und Argon in einer Rohargonsäule hingewiesen, die Packungen enthält und eine sehr hohe Trennstufenzahl aufweist (EP-A-0 377 l17). Es ergibt sich damit eine sehr große Bauhöhe der Rohargonsäule. Durch den erfindungsgemäßen Einsatz einer Packung mit sehr hoher spezifischer Oberfläche, beispielsweise 1200 oder 1500 m2/m3, können die Bauhöhe einer derartigen Rohargonsäule und damit die Investitionskosten für die Anlage entscheidend reduziert werden.As an example, reference is made here to a process for the purely rectifying separation of oxygen and argon in a crude argon column which contains packings and has a very high number of separation stages (EP-A-0 377 1117). This results in a very large overall height of the raw argon column. By using a package according to the invention with a very high specific surface area, for example 1200 or 1500 m 2 / m 3 , the overall height of such a crude argon column and thus the investment costs for the system can be significantly reduced.

Vorzugsweise wird der Stoffaustausch mindestens in einem Teilbereich der Rektifiziersäule beziehungsweise der Rohargonsäule durch eine geordnete Packung bewirkt, die eine spezifische Oberfläche mindestens 1100 m2/m3 aufweist.The mass transfer is preferably effected at least in a partial area of the rectification column or the crude argon column by an ordered packing which has a specific surface area of at least 1100 m 2 / m 3 .

Vorteilhaft ist außerdem die Anwendung der Erfindung auf ein Doppelsäulenverfahren, bei dem das Destilliersystem eine Drucksäule und eine Niederdrucksäule aufweist, wobei mindestens ein Teil der gereinigten und abgekühlten Luft in die Drucksäule eingeleitet wird und eine sauerstoffangereicherte und eine stickstoffreiche Fraktion aus der Drucksäule in die Niederdrucksäule eingeleitet werden. Diese Doppelsäule kann beispielsweise ausschließlich zur Gewinnung von Sauerstoff und/oder Stickstoff dienen, oder es können zusätzliche Trennsäulen zur Gewinnung von Edelgasen angeschlossen sein.It is also advantageous to apply the invention to a double-column process in which the distillation system has a pressure column and a low-pressure column, at least some of the cleaned and cooled air being introduced into the pressure column and an oxygen-enriched and a nitrogen-rich fraction from the pressure column in the low pressure column are introduced. This double column can, for example, serve exclusively for the production of oxygen and / or nitrogen, or additional separation columns can be connected for the production of noble gases.

Durch die Verbindung mit der in aller Regel unterhalb der Niederdrucksäule angeordneten Drucksäule bewirkt die durch die Erfindung verringerte Bauhöhe einen besonders großen Vorteil. Es kann unter Umständen auf ansonsten benötigte Pumpen zur Förderung der flüssigen Fraktionen aus der Drucksäule zur Niederdrucksäule verzichtet werden. Dies gilt insbesondere dann, wenn der Kopf der Niederdrucksäule durch indirekten Wärmeaustausch mit einer Fraktion aus dem unteren Bereich der Drucksäule gekühlt wird. Beim erfindungsgemäßen Einsatz der dichten Packung kann sogar die Höhendifferenz zwischen Sumpf der Drucksäule und Kopf der Niederdrucksäule allein durch die vorhandene Druckdifferenz überwunden werden.Due to the connection to the pressure column, which is generally arranged below the low-pressure column, the height reduced by the invention has a particularly great advantage. Under certain circumstances, pumps otherwise required for conveying the liquid fractions from the pressure column to the low pressure column can be dispensed with. This is especially true when the head of the low pressure column is cooled by indirect heat exchange with a fraction from the lower area of the pressure column. When using the dense packing according to the invention, even the height difference between the sump of the pressure column and the head of the low pressure column can be overcome solely by the pressure difference present.

Falls nur Teile der Niederdrucksäule mit der Packung hoher spezifischer Oberfläche ausgestattet werden, ist es günstig, wenn der Stoffaustausch in dem Abschnitt der Niederdrucksäule, der unterhalb der Einspeisestelle der sauerstoffangereicherten Fraktion aus der Drucksäule liegt, mindestens teilweise durch eine Packung bewirkt wird, die eine spezifische Oberfläche von mehr als 1000 m2/m3 aufweist. Dieser Abschnitt wird allgemein als Sauerstoffabschnitt bezeichnet. Da die Einspeisungen der beiden Fraktionen aus der Drucksäule oberhalb dieses Abschnittes liegen, weist dieser eine relativ geringe Belastung auf.If only parts of the low-pressure column are equipped with the pack of high specific surface area, it is advantageous if the mass transfer in the section of the low-pressure column, which lies below the point where the oxygen-enriched fraction from the pressure column is fed in, is at least partially effected by a pack which has a specific Has surface area of more than 1000 m 2 / m 3 . This section is commonly referred to as the oxygen section. Since the feeds of the two fractions from the pressure column lie above this section, this section has a relatively low load.

Ähnliches gilt für den Rein-Stickstoff-Abschnitt, der zwischen dem Kopf der Niederdrucksäule, an dem eine Rein-Stickstofffraktion entnommen wird und der Entnahmestelle einer Unrein-Stickstofffraktion unterhalb des Kopfes liegt, und für den Argon-Zwischenabschnitt. Letzterer befindet sich zwischen der Entnahmestelle eines argonhaltigen Sauerstoffstroms, der zur Rohargonsäule geführt wird und der Einspeisestelle einer in indirektem Wärmeaustausch mit Gas vom Kopf der Rohargonsäule verdampften Fraktion. Bevorzugt wird in einem dieser Abschnitte oder in beiden der Stoffaustausch mindestens teilweise durch eine Packung bewirkt, die eine spezifische Oberfläche von mehr als 1000 m2/m3 aufweist.The same applies to the pure nitrogen section, which lies between the head of the low-pressure column, from which a pure nitrogen fraction is removed, and the removal point of an impure nitrogen fraction below the head, and to the intermediate argon section. The latter is located between the point of withdrawal of an argon-containing oxygen stream which is led to the crude argon column and the feed point of a fraction evaporated from the top of the crude argon column in indirect heat exchange with gas. In one or both of these sections, the mass transfer is preferably effected at least partially by a packing which has a specific surface area of more than 1000 m 2 / m 3 .

Zusätzlich kann auch der Stoffaustausch in der Drucksäule mindestens teilweise durch eine Packung bewirkt werden. Es kann sich dabei um eine Packung hoher spezifischer Oberfläche handeln, aber auch der Einsatz einer weniger dichten Packung ist möglich. Seltener kommt der Einsatz einer sehr dichten Packung ausschließlich in der Drucksäule in Frage.In addition, the mass exchange in the pressure column can also be effected at least partially by a packing. It can be a pack with a high specific surface area, but also the use of a less dense one Packing is possible. The use of a very dense packing is only rarely used in the pressure column.

Die Erfindung betrifft außerdem eine Luftzerlegungsanlage gemäß den Patentansprüchen 15 und 21.The invention also relates to an air separation plant according to claims 15 and 21.

Die Patentansprüche 16 bis 20 und 22 bis 28 betreffen besondere Ausführungsarten dieser erfindungsgemäßen Luftzerlegungsanlagen.Claims 16 to 20 and 22 to 28 relate to special embodiments of these air separation plants according to the invention.

Im folgenden werden die Erfindung sowie weitere Einzelheiten der Erfindung anhand von Ausführungsbeispielen näher erläutert, die in den Zeichnungen schematisch dargestellt sind. Die in den Figuren gezeigten Verfahren weisen jeweils mindestens zwei Rektifizierstufen auf; die Erfindung ist jedoch auch auf einstufige Luftzerlegungsverfahren anwendbar.The invention and further details of the invention are explained in more detail below with reference to exemplary embodiments which are shown schematically in the drawings. The methods shown in the figures each have at least two rectification stages; however, the invention is also applicable to single stage air separation processes.

Es zeigen im einzelnen:

Figur 1
ein Luftzerlegungsverfahren gemäß der Erfindung mit drei Abschnltten in der Niederdrucksäule,
Figur 2
ein Verfahren mit vier Abschnitten in der Niederdrucksäule, bei dem zusätzlich ein Teil der Luft direkt in die Niederdrucksäule eingeblasen wird,
Figur 3
eine andere Variante des erfindungsgemäßen Verfahrens mit einer der Niederdrucksäule angeschlossenen Rohargonsäule und fünf Abschnitten in der Niederdrucksäule und
Figur 4
eine weitere Variante mit Rohargonsäule und direkter Lufteinblasung mit sechs Abschnitten in der Niederdrucksäule.
The individual shows:
Figure 1
an air separation process according to the invention with three sections in the low pressure column,
Figure 2
a process with four sections in the low-pressure column, in which part of the air is additionally blown directly into the low-pressure column,
Figure 3
another variant of the method according to the invention with a crude argon column connected to the low pressure column and five sections in the low pressure column and
Figure 4
another variant with raw argon column and direct air injection with six sections in the low pressure column.

Die einander entsprechenden Verfahrensschritte und Vorrichtungsmerkmale sind in den Ausführungsbeispielen mit denselben Bezugszeichen versehen.The corresponding method steps and device features are provided with the same reference symbols in the exemplary embodiments.

Bei dem in dem Schema von Figur 1 dargestellten Verfahren wird gereinigte Luft 1 unter einem Druck von 4 bis 20 bar, vorzugsweise 5 bis 12 bar in einem Wärmetauscher 2 gegen Produktströme auf etwa Taupunkt abgekühlt und in die Drucksäule 3 einer zweistufigen Rektifiziereinrichtung eingespeist. Die Drucksäule 3 steht über einen gemeinsamen Kondensator-Verdampfer 4 in Wärmeaustauschbeziehung zu einer Niederdrucksäule 5.In the process shown in the diagram of FIG. 1, cleaned air 1 is cooled under a pressure of 4 to 20 bar, preferably 5 to 12 bar, in a heat exchanger 2 against product flows to approximately dew point and fed into the pressure column 3 of a two-stage rectification device. The pressure column 3 is in heat exchange relationship with a low-pressure column 5 via a common condenser-evaporator 4.

Sumpfflüssigkeit 6 und Stickstoff 7 werden aus der Drucksäule 3 abgezogen, in einem Gegenströmer 8 unterkühlt und in die Niederdrucksäule 5 eingedrosselt. Aus der Niederdrucksäule werden Sauerstoff 9, Stickstoff 10 und unreiner Stickstoff 11 entnommen. Die Produkte können auch mindestens teilweise flüssig entnommen werden. Dies ist der Übersichtlichkeit halber in den Verfahrensschemen nicht dargestellt.Bottom liquid 6 and nitrogen 7 are withdrawn from the pressure column 3, subcooled in a countercurrent 8 and throttled into the low pressure column 5. Oxygen 9, nitrogen 10 and impure nitrogen 11 are removed from the low pressure column. The products can also be removed at least partially in liquid form. For the sake of clarity, this is not shown in the process diagrams.

Die Niederdrucksäule 5 weist in Verfahren und Vorrichtung von Figur 1 folgende Abschnitte auf:

A
Rein-Stickstoff-Abschnitt (oberhalb der Unreinstickstoffleitung 11)
B
Unrein-Stickstoff-Abschnitt (begrenzt durch Unreinstickstoffleitung 11 und Sumpfflüssigkeitsleitung 6)
E
Sauerstoff-Abschnitt (unterhalb der Mündung der Sumpfflüssigkeitsleitung 6)
The low-pressure column 5 has the following sections in the method and device of FIG. 1:
A
Pure nitrogen section (above impure nitrogen line 11)
B
Impure nitrogen section (limited by impure nitrogen line 11 and bottom liquid line 6)
E
Oxygen section (below the mouth of the sump liquid line 6)

Bei dem in Figur 2 dargestellten Ausführungsform von erfindungsgemäßem Verfahren und Vorrichtung gemäß der Erfindung wird ein Teil der zu zerlegenden Luft in einer Turbine 12 arbeitsleistend entspannt und über Leltung 13 unter Umgehung der Vorzerlegung in Drucksäule 3 direkt in die Niederdrucksäule 5 eingeblasen. Die Turbinenluft 13 kann dabei beispielsweise in Höhe der Sumpfflüssigkeitsleitung 6 in die Niederdrucksäule eingespeist werden; günstiger ist jedoch eine Zuführung im Bereich unterhalb der Sumpfflüssigkeitseinführung, wie sie in Figur 2 dargestellt ist. Dadurch werden in der Niederdrucksäule insgesamt vier Abschnitte definiert:

A und B
wie in Figur 1
C
Unrein-Sauerstoff-Abschnitt (begrenzt durch Sumpfflüssigkeitsleitung 6 und Einblaseleitung 13 für Turbinenluft)
E
Sauerstoff-Abschnitt (unterhalb der Mündung der Einblaseleitung 13)
In the embodiment of the method and device according to the invention shown in FIG. 2, part of the air to be broken down is expanded in a turbine 12 in a work-performing manner and is blown directly into the low-pressure column 5 via ventilation 13, bypassing the pre-separation in the pressure column 3. The turbine air 13 can, for example, be fed into the low-pressure column at the level of the sump liquid line 6; However, a feed in the area below the bottom liquid inlet, as shown in FIG. 2, is more favorable. This defines a total of four sections in the low pressure column:
A and B
as in Figure 1
C.
Impure oxygen section (limited by sump liquid line 6 and injection line 13 for turbine air)
E
Oxygen section (below the mouth of the injection line 13)

Figur 3 zeigt eine der Luftrektifikation angeschlossene Rohargonsäule 15. Uber Argonübergangsleitung 14 wird ein argonhaltiger Sauerstoffstrom aus dem unteren Bereich der Niederdrucksäule 5 (unterhalb der Sumpfflüssigkeitsleitung 6) entnommen, in den unteren Bereich der Rohargonsäule 15 geleitet und dort in ein Rohargonprodukt 16 und eine Restfraktion 17 zerlegt. Die Restfraktion wird in die Niederdrucksäule zurückgeleitet. Sie kann entweder über die Leitung 14 zurückfließen (falls ein entsprechendes Gefälle vorhanden ist) oder, wie in Figur 3 gezeigt, mittels einer Pumpe 18 über eine eigene Leitung 17 gefördert werden.FIG. 3 shows a crude argon column 15 connected to the air rectification. An argon-containing oxygen stream is taken from the lower region of the low-pressure column 5 (below the bottom liquid line 6) via argon transfer line 14, passed into the lower region of the crude argon column 15 and there into a crude argon product 16 and a residual fraction 17 disassembled. The remaining fraction is returned to the low pressure column. It can either flow back via line 14 (if a corresponding gradient is present) or, as shown in FIG. 3, can be conveyed by means of a pump 18 via its own line 17.

Der Kopf der Rohargonsäule wird durch einen Rohargonkondensator 19 gekühlt, auf dessen Verdampfungsseite über Leitung 20 herangeführte Sumpfflüssigkeit aus der Drucksäule 3 verdampft. Die verdampfte Fraktion wird über Leitung 21 zur Niederdrucksäule geführt. Sie kann beispielweise auf Höhe der Sumpfflüssigkeitsleitung 6 eingeleitet werden. Besonders vorteilhaft ist jedoch eine Einspeisung zwischen Mündung der Sumpfflüssigkeitsleitung 6 und Anschluß der Argonübergangsleitung.The head of the crude argon column is cooled by a crude argon condenser 19, on the evaporation side of which sump liquid which is brought in via line 20 evaporates from the pressure column 3. The evaporated fraction is fed via line 21 to the low pressure column. It can be introduced, for example, at the level of the sump liquid line 6. However, a feed between the mouth of the sump liquid line 6 and the connection of the argon transfer line is particularly advantageous.

Durch die beschriebene Verfahrensweise ergeben sich in der Niederdrucksäule von Figur 3 folgende Unterteilungen:

A und B
wie in Figur 1
C
Unrein-Sauerstoff-Abschnitt (begrenzt durch Sumpfflüssigkeitsleitung 6 und Leitung 21 zur Einführung der verdampften Fraktion aus dem Rohargonkondensator 19)
D
Argon-Zwischenabschnitt (begrenzt durch Leitung 21 zur Einführung der verdampften Fraktion aus dem Rohargonkondensator 19 und Entnahmeleitung 14 für die in der Rohargonsäule zu zerlegende argonhaltige Sauerstofffraktion)
E
Sauerstoff-Abschnitt (unterhalb der Entnahmeleitung 14 für die in der Rohargonsäule zu zerlegende argonhaltige Sauerstofffraktion)
The procedure described results in the following subdivisions in the low pressure column of FIG. 3:
A and B
as in Figure 1
C.
Impure oxygen section (limited by bottom liquid line 6 and line 21 for introducing the vaporized fraction from the crude argon condenser 19)
D
Intermediate argon section (delimited by line 21 for introducing the vaporized fraction from the crude argon condenser 19 and removal line 14 for the argon-containing oxygen fraction to be broken down in the crude argon column)
E
Oxygen section (below the extraction line 14 for the argon-containing oxygen fraction to be broken down in the crude argon column)

In Figur 4 ist eine Kombination der Varianten der Figuren 2 und 3 dargestellt. Ausgehend von Figur 3 wird als zusätzliches Merkmal in einer Turbine 12 arbeitsleistend entspannte Luft direkt in die Niederdrucksäule 5 eingeblasen. Ähnllch wie beim Verfahren der Figur 2 ist es möglich, die Turbinenluft beispielsweise in Höhe der Sumpfflüssigkeitsleitung 6 einzuführen. Bevorzugt wird sie, wie in Figur 4 gezeigt, im Bereich zwischen Sumpfflüssigkeitseinführung 6 und Einleitung der verdampften Fraktion 21 aus dem Rohargonkondensator 19 eingespeist. So wird der Unrein-Sauerstoff-Abschnitt weiter in zwei Unterabschnitte C1 und C2 unterteilt.FIG. 4 shows a combination of the variants in FIGS. 2 and 3. Starting from FIG. 3, as an additional feature, relaxed air is blown directly into the low-pressure column 5 in a turbine 12. Similar to the method in FIG. 2, it is possible to introduce the turbine air, for example, at the level of the bottom liquid line 6. It is preferably, as shown in FIG. 4, fed in from the crude argon condenser 19 in the region between the bottom liquid inlet 6 and the introduction of the vaporized fraction 21. So the impure oxygen section is further divided into two subsections C 1 and C 2 .

Erfindungsgemäß wird der Stoffaustausch in einigen Abschnitten der Niederdrucksäule 5 mindestens teilweise durch eine Packung bewirkt, die eine spezifische Oberfläche von mehr als 1000 m2/m3 aufweist, und/oder der Stoffaustausch in der Rohargonsäule 15 wird mindestens teilweise durch eine Packung bewirkt, die eine spezifische Oberfläche von mindestens 1000 m2/m3 aufweist.According to the invention, the mass transfer in some sections of the low-pressure column 5 is at least partially effected by a packing which has a specific surface area of more than 1000 m 2 / m 3 , and / or the mass transfer in the crude argon column 15 is at least partially effected by a packing which has a specific surface area of at least 1000 m 2 / m 3 .

Zur Verwirklichung der Erfindung müssen nicht in jedem Abschnitt der Niederdrucksäule Packungen eingesetzt werden; in einem oder mehreren Abschnitten kann der Stoffaustausch auch teilweise oder ausschließlich durch andere Stoffaustauschelemente bewirkt werden, beispielsweise durch konventionelle Rektifizierböden wie Glocken- oder Siebböden. In einem Abschnitt, in dem in einem oder in mehreren Teilbereichen eine Packung angeordnet ist, kann der Stoffaustausch in anderen Teilbereichen durch andere Stoffaustauschelemente bewerkstelligt werden. Bevorzugt werden in allen Abschnitten der Niederdrucksäule 5 hauptsächlich Packungen eingesetzt, um den Stoffaustausch zu bewirken.Packs do not have to be used in every section of the low-pressure column to implement the invention; in one or more sections, the mass transfer can also be effected partially or exclusively by other mass transfer elements, for example by conventional rectification trays such as bubble-cap trays or sieve trays. In a section in which a packing is arranged in one or more sub-areas, the mass transfer in other sub-areas can be brought about by other mass transfer elements. Preferably, packs are mainly used in all sections of the low-pressure column 5 in order to effect the mass transfer.

Eine einfache Form der Realisierung der Erfindung ist ein Verfahren gemäß Figur 1, bei dem in einem Stickstoffabschnitt, beispielsweise dem im Sauerstoff-Abschnitt E und/oder im Rein-Stickstoff-Abschnitt eine Packung mit einer spezifische Oberfläche von mehr als 1000 m2/m3 eingesetzt wird.A simple form of realizing the invention is a method according to FIG. 1, in which in a nitrogen section, for example in the oxygen section E and / or in the pure nitrogen section, a packing with a specific surface area of more than 1000 m 2 / m 3 is used.

Die folgende Tabelle zeigt ein Zahlenbeispiel für eine Niederdrucksäule mit fünf Abschnitten gemäß Figur 3. Die Bezeichnung der Abschnitte in den Ausführungsbeispielen der übrigen Figuren ist so gewählt, daß die Werte der Tabelle unmittelbar auf diese Varianten übertragen werden können. Die Tabelle enthält für jeden der Abschnitte A bis E einen Zahlenbereich für die Belastung (Durchsatz an aufsteigendem Gas) relativ zum Unrein-Stickstoff-Abschnitt B, einen bevorzugten Zahlenbereich für eine in dem Abschnitt einzusetzende Packung sowie zwei besonders bevorzugte Zahlenwerte von konkreten Ausführungsbeispielen. TABELLE Abschnitt relative Belastung % spezifische Oberfläche m2/m3 A Rein-Stickstoff-Abschnitt 60-75 600-1250 750 1100 B Unrein-Stickstoff-Abschnitt 100 350-800 500 750 C Unrein-Sauerstoff-Abschnitt ca.90 350-800 500 750 D Argon-Zwischenabschnitt 40-50 600-1500 1100 1250 E Sauerstoff-Abschnitt 75-85 500-1250 750 1100 The following table shows a numerical example for a low-pressure column with five sections according to FIG. 3. The designation of the sections in the exemplary embodiments of the other figures is chosen so that the values in the table can be transferred directly to these variants. For each of the sections A to E, the table contains a range of numbers for the load (throughput of rising gas) relative to the impure nitrogen section B, a preferred range of numbers for a pack to be used in the section and two particularly preferred numerical values of specific exemplary embodiments. TABLE section relative load% specific surface area m 2 / m 3 A Pure nitrogen section 60-75 600-1250 750 1100 B Impure nitrogen section 100 350-800 500 750 C. Impure oxygen section about 90 350-800 500 750 D Argon intermediate section 40-50 600-1500 1100 1250 E Oxygen section 75-85 500-1250 750 1100

Aus der Tabelle ist ersichtlich, daß im Abschnitt B, der am höchsten belastet ist, eine relativ grobe Packung zum Einsatz kommt. Niedriger belastete Abschnitte, beispielsweise Abschnitt E, werden vorzugsweise mit feineren Packungen ausgestattet. Der Argon-Zwischenabschnitt D enthält bevorzugt eine Packung mit besonders hoher spezifischer Oberfläche. Der Wert 1500 m2/m3 ist dabei keine Obergrenze, grundsätzlich sind auch höhere spezifische Oberflächen denkbar.From the table it can be seen that in section B, which is most heavily loaded, a relatively coarse packing is used. Sections with a lower load, for example section E, are preferably provided with finer packs. The intermediate argon section D preferably contains a pack with a particularly high specific surface area. The value of 1500 m 2 / m 3 is not an upper limit, in principle higher specific surfaces are also conceivable.

Die in verschiedenen Abschnitten eingesetzten Packungen können ansonsten gleiche oder verschiedene Struktur aufweisen. Bevorzugt werden jedoch in einem, mehreren oder allen Abschnitten geordnete Packungen eingesetzt, wie sie in der WO-A-9319335 mit gleichem Zeitrang beschrieben sind. Verschiedene spezifische Oberflächen werden durch verschiedene Amplituden bei der Faltung der Lamellen erzeugt, aus denen die Packung hergestellt ist.The packs used in different sections can otherwise have the same or different structure. However, it is preferred to use packs arranged in one, several or all sections, as described in WO-A-9319335 with the same priority. Different specific surfaces are created by different amplitudes in the folding of the slats from which the package is made.

Durch den erfindungsgemäßen Einsatz von Packungen sehr hoher spezifischer Oberfläche fällt die Bauhöhe der Niederdrucksäule 5 der Ausführungsbeispiele wesentlich geringer aus als beispielsweise beim ausschließlichen Einsatz von Packungen einer spezifischen Oberfläche von weniger als 1000 m2/m3.Due to the use of packs of very high specific surface area according to the invention, the overall height of the low-pressure column 5 of the exemplary embodiments is significantly lower than, for example, when packs with a specific surface area of less than 1000 m 2 / m 3 are used exclusively.

In den Ausführungsbeispielen der Figuren 1 bis 4 beziehungsweise 3 und 4 kann auch in der Drucksäule 3 und/oder insbesondere in der Rohargonsäule 15 der Stoffaustausch in einem oder mehreren Teilbereichen oder in der gesamten Kolonne durch Packungen bewirkt werden. Diese weisen vorzugsweise ebenfalls die in der WO-A-9319335 beschriebene Struktur auf.In the exemplary embodiments in FIGS. 1 to 4 or 3 and 4, the mass transfer in one or more partial areas or in the entire column can also be effected by packing in the pressure column 3 and / or in particular in the crude argon column 15. These preferably also have the structure described in WO-A-9319335.

Es können auch in der Rohargonsäule Packungen unterschiedlicher spezifischer Oberfläche eingesetzt werden, vorzugsweise wird jedoch eine Packung mit konstanter spezifischer Oberfläche verwendet. Die besonders bevorzugten Werte der spezifischen Oberfläche dieser Packung liegen bei 1000 bis 1500 m2/m3, vorzugsweise bei 1100 bis 1250 m2/m3. Bevorzugt findet im wesentlichen der gesamte Stoffaustausch in der Rohargonsäule 15 an einer derart dichten Packung statt.Packs of different specific surface areas can also be used in the crude argon column, but a pack with a constant specific surface area is preferably used. The particularly preferred values of the specific surface area of this packing are 1000 to 1500 m 2 / m 3 , preferably 1100 to 1250 m 2 / m 3 . Preferably, essentially the entire mass transfer in the crude argon column 15 takes place on such a tight packing.

Falls bereits in der Niederdrucksäule oder in der Drucksäule eine Packung mit einer spezifischen Oberfläche von mehr als 1000 m2/m3 eingesetzt wird, können die Packungsdichte in der Rohargonsäule auch unterhalb dieser Grenze liegen, vorzugsweise bei 700 bis 900 m2/m3, insbesondere bei ca. 750 m2/m3.If a packing with a specific surface area of more than 1000 m 2 / m 3 is already used in the low pressure column or in the pressure column, the packing density in the crude argon column can also be below this limit, preferably 700 to 900 m 2 / m 3 , in particular at approx. 750 m 2 / m 3 .

Besonders günstig ist der Einsatz einer besonders dichten Packung außerdem bei Luftzerlegungsanlagen und -verfahren, bei denen eine Rektifiziersäule in einen Vakuumbehälter, beispielsweise einen Flüssigkeitstank eingebaut ist. (Einzelheiten zu derartigen Verfahren und Vorrichtungen sind der DE-A-41 35 302 zu entnehmen.) Durch den Einbau einer Packung mit einer spezifischen Oberfläche von - mehr als 1000 m2/m3 in einen oder mehrere Teilbereiche oder in den gesamten für den Stoffaustausch wirksamen Bereich einer derartigen Säule kann deren Bauhöhe verringert werden. Es vermindern sich damit nicht nur die Herstellungskosten der Säule selbst, sondern auch diejenigen des sie umschließenden Vakuumbehälters.The use of a particularly dense packing is also particularly favorable in air separation plants and processes in which a rectification column is installed in a vacuum container, for example a liquid tank. (Details of such methods and devices can be found in DE-A-41 35 302.) By installing a pack with a specific surface area of - more than 1000 m 2 / m 3 in one or more sub-areas or in the whole for the Mass transfer effective area of such a column can be reduced in height. This not only reduces the manufacturing costs of the column itself, but also those of the vacuum container surrounding it.

Daneben ist auch die Anwendung der Erfindung auf Verfahren und Vorrichtungen vorteilhaft, bei denen flüssig gewonnener Sauerstoff gegen eine kondensierende Fraktion (beispielsweise Hochdruckluft) verdampft wird. Bei solchen Verfahren wird das Sauerstoffprodukt oftmals flüssig auf Druck gebracht (sogenannte Innenverdichtung), beispielsweise durch Ausnutzung eines hydrostatischen Potentials oder durch eine Pumpe. Im Falle der Einspeisung von gegen verdampfenden Sauerstoff kondensierter Luft an einer mittleren Stelle der Drucksäule kann es günstig sein, oberhalb und unterhalb dieser Einspeisestelle verschieden dichte Packungen in der Drucksäule zu verwenden.In addition, the application of the invention to methods and devices in which liquid oxygen is evaporated against a condensing fraction (for example high-pressure air) is also advantageous. In such processes, the oxygen product is often brought under pressure in liquid form (so-called internal compression), for example by using a hydrostatic potential or by a pump. If air condensed against evaporating oxygen is fed into a central point of the pressure column, it may be expedient to use packings of different densities in the pressure column above and below this feed point.

Claims (28)

  1. Process for the low-temperature fractionation of air, in which purified and cooled air is passed into a distillation system having at least one rectifying column and is there rectified by countercurrent mass transfer between a vapour phase and a liquid phase, the mass transfer being effected in at least one partial area of at least one rectifying column by an arranged packing, characterized in that the mass transfer is effected in at least one partial area of at least one rectifying column by an arranged packing which has a specific surface area of more than 1,000 m2/m3.
  2. Process according to Claim 1, characterized in that the mass transfer in the uppermost section of the rectifying column is effected at least in part by a packing which has a specific surface area of more than 1,000 m2/m3.
  3. Process according to Claim 1 or 2, characterized in that the mass transfer in the lowest section of the rectifying column is effected at least in part by a packing which has a specific surface area of more than 1,000 m2/m3.
  4. Process according to one of Claims 1 to 3, characterized in that the or a rectifying column in which the mass transfer is effected in at least a partial area at least in part by a packing which has a specific surface area of more than 1,000 m2/m3 is constructed as a low-pressure column.
  5. Process according to one of Claims 1 to 4, characterized in that the distillation system has a low-pressure column and a crude argon column and in that an argon-containing oxygen stream is withdrawn from the low-pressure column and is fractionated in the crude argon column into crude argon and a residual fraction.
  6. Process according to Claim 5, characterized in that the mass transfer is effected at least in a partial area of the crude argon column by a packing which has a specific surface area of at least 1,000 m2/m3.
  7. Process for the low-temperature fractionation of air, in which purified and cooled air is passed into a distillation system which has at least two rectifying columns, including a low-pressure column and a crude argon column, and is there rectified by countercurrent mass transfer between a vapour phase and a liquid phase in each case, in the process an argon-containing oxygen stream being withdrawn from the low-pressure column and being fractionated in the crude argon column into crude argon and a residual fraction and the mass transfer being effected in at least a partial area of the crude argon column by an arranged packing, characterized in that the mass transfer is effected at least in a partial area of the crude argon column by an arranged packing which has a specific surface area of at least 1,000 m2/m3.
  8. Process according to one of Claims 1 to 7, characterized in that the mass transfer is effected at least in a partial area of the rectifying column or the crude argon column by an arranged packing which has a specific surface area of at least 1100 m2/m3.
  9. Process according to one of Claims 1 to 7, characterized in that the distillation system has a pressure column and a low-pressure column, at least some of the purified and cooled air being introduced into the pressure column and an oxygen-enriched fraction and a nitrogen-rich fraction being introduced from the pressure column into the low-pressure column.
  10. Process according to Claim 9, in which an argon-containing oxygen stream is withdrawn from the low-pressure column beneath the feed-in point of the oxygen-enriched fraction and is fractionated in a crude argon column into crude argon and a residual fraction, and in which gas from the top of the crude argon column is brought into indirect heat exchange with an evaporating fraction from the pressure column, the fraction which is evaporated in the indirect heat exchange being introduced into the low-pressure column, characterized in that the mass transfer in the section of the low-pressure column which is situated between the feed-in point of the evaporated fraction and the take-off point of the argon-containing oxygen stream is effected at least in part by a packing which has a specific surface area of more than 1,000 m2/m3.
  11. Process according to Claim 9 or 10, characterized in that the mass transfer in the section of the low-pressure column which is situated below the feed-in point of the oxygen-enriched fraction from the pressure column is effected at least in part by a packing which has a specific surface area of more than 1,000 m2/m3.
  12. Process according to one of Claims 4 to 11, characterized in that a pure nitrogen fraction is withdrawn from the top of the low-pressure column and an impure nitrogen fraction is withdrawn below the top and in that the mass transfer in the section of the low-pressure column which is situated between the take-off points of pure and impure nitrogen is effected at least in part by a packing which has a specific surface area of more than 1,000 m2/m3.
  13. Process according to one of Claims 9 to 11, characterized in that the mass transfer in the pressure column is effected at least in part by a packing.
  14. Process according to Claim 13, characterized in that the mass transfer in at least a partial area of the pressure column is effected by a packing which has a specific surface area of at least 1,000 m2/m3.
  15. Air fractionation plant having a distillation system which has at least one rectifying column which contains mass transfer elements, the mass transfer elements in at least a partial area of at least one rectifying column being formed by an arranged packing which has a specific surface area of more than 1,000 m2/m3.
  16. Air fractionation plant according to Claim 15, characterized in that the mass transfer elements in the uppermost section of the rectifying column are formed at least in part by a packing which has a specific surface area of more than 1,000 m2/m3.
  17. Air fractionation plant according to Claim 15 or 16, characterized in that the mass transfer elements in the lowest section of the rectifying column are formed at least in part by a packing which has a specific surface area of more than 1,000 m2/m3.
  18. Air fractionation plant according to one of Claims 15 to 17, characterized in that the or a rectifying column in which the mass transfer elements are formed at least in part by a packing which has a specific surface area of more than 1,000 m2/m3 is constructed as a low-pressure column.
  19. Air fractionation plant according to one of Claims 15 to 18, characterized in that the distillation system has a low-pressure column and a crude argon column and in that low-pressure column and crude argon column are connected together via an argon transfer line.
  20. Air fractionation plant according to Claim 19, characterized in that the mass transfer elements at least in a partial area of the crude argon column are formed by a packing which has a specific surface area of at least 1,000 m2/m3.
  21. Air fractionation plant having a distillation system which has a low-pressure column and a crude argon column which contain mass transfer elements and are connected together via an argon transfer line, characterized in that the mass transfer elements at least in a partial area of the crude argon column are formed by an arranged packing which has a specific surface area of at least 1,000 m2/m3.
  22. Air fractionation plant according to one of Claims 15 to 21, characterized in that at least in a partial area of the rectifying column or the crude argon column the mass-transfer elements are formed by an arranged packing which has a specific surface area of at least 1100 m2/m3.
  23. Air fractionation plant according to one of Claims 15 to 22, characterized in that the distillation system has a pressure column and a low-pressure column, a feed line for the air to be fractionated opening into the pressure column and a bottom-phase liquid line and a pressure nitrogen line leading from the pressure column into the low-pressure column.
  24. Air fractionation plant according to Claim 23, in which an argon transfer line is connected to the low-pressure column below the opening of the bottom liquid-phase line and leads into a crude argon column which has a top condenser whose evaporation space is connected via a liquid line to the pressure column and via a gas line to the low-pressure column, characterized in that the mass-transfer elements in the section of the low-pressure column which is between the opening of the gas line and the argon transfer line are formed at least in part by a packing which has a specific surface area of more than 1,000 m2/m3.
  25. Air fractionation plant according to Claim 23 or 24, characterized in that the mass-transfer elements in the section of the low-pressure column which is situated below the opening of the bottom liquid-phase line are formed at least in part by a packing which has a specific surface area of more than 1,000 m2/m3.
  26. Air fractionation plant according to one of Claims 20 to 25, characterized by a pure nitrogen line which is connected to the upper region of the low-pressure column and by an impure nitrogen line which is connected to the low-pressure column below the pure nitrogen line, the mass-transfer elements in the section of the low-pressure column which is arranged between pure nitrogen line and impure nitrogen line being formed at least in part by a packing which has a specific surface area of more than 1,000 m2/m3.
  27. Air fractionation plant according to one of Claims 23 to 26, characterized in that the mass-transfer elements in the pressure column are formed at least in part by a packing.
  28. Air fractionation plant according to one of Claims 23 to 27, characterized in that the mass transfer in at least a partial area of the pressure column is effected by a packing which has a specific surface area of at least 1,000 m2/m3.
EP93920521A 1992-03-20 1993-03-17 Process for the low-temperature air separation and air separation plant Revoked EP0636237B1 (en)

Applications Claiming Priority (5)

Application Number Priority Date Filing Date Title
DE4209131 1992-03-20
DE4209131 1992-03-20
DE4224068 1992-07-21
DE4224068A DE4224068A1 (en) 1992-03-20 1992-07-21 METHOD FOR DEEP TEMPERATURE DISASSEMBLY OF AIR AND AIR DISASSEMBLY SYSTEM
PCT/EP1993/000623 WO1993019336A1 (en) 1992-03-20 1993-03-17 Process for the low-temperature air separation and air separation plant

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EP0636237A1 EP0636237A1 (en) 1995-02-01
EP0636237B1 true EP0636237B1 (en) 1997-01-02

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US (1) US5613374A (en)
EP (1) EP0636237B1 (en)
JP (1) JPH07504742A (en)
CN (1) CN1073227C (en)
AU (1) AU3749493A (en)
CA (1) CA2132524A1 (en)
DE (2) DE4224068A1 (en)
RU (1) RU2107871C1 (en)
WO (1) WO1993019336A1 (en)

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EP2645031A1 (en) 2012-03-29 2013-10-02 Linde Aktiengesellschaft Separating column for a low temperature air separator facility, low temperature air separator facility and method for low temperature separation of air
EP2645033A1 (en) 2012-03-29 2013-10-02 Linde Aktiengesellschaft Transportable package with a cold box and method for manufacturing a low temperature air separator facility
DE102013003417A1 (en) 2012-03-29 2013-10-02 Linde Aktiengesellschaft Separation column for a cryogenic air separation plant, cryogenic air separation plant and process for the cryogenic separation of air
DE102012006484A1 (en) 2012-03-29 2013-10-02 Linde Aktiengesellschaft Transportable package with a coldbox and method of manufacturing a cryogenic air separation plant
WO2013143646A2 (en) 2012-03-29 2013-10-03 Linde Aktiengesellschaft Transportable package with a cold box, and method for producing a low-temperature air separation system
DE202013012594U1 (en) 2012-03-29 2017-10-11 Linde Aktiengesellschaft Transportable package with a coldbox

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RU94043327A (en) 1996-08-20
AU3749493A (en) 1993-10-21
WO1993019336A1 (en) 1993-09-30
CN1080991A (en) 1994-01-19
CA2132524A1 (en) 1993-09-30
EP0636237A1 (en) 1995-02-01
DE4224068A1 (en) 1993-09-23
RU2107871C1 (en) 1998-03-27
CN1073227C (en) 2001-10-17
JPH07504742A (en) 1995-05-25
US5613374A (en) 1997-03-25

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