EP0505812B1 - Low temperature air separation process - Google Patents

Low temperature air separation process Download PDF

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Publication number
EP0505812B1
EP0505812B1 EP92104008A EP92104008A EP0505812B1 EP 0505812 B1 EP0505812 B1 EP 0505812B1 EP 92104008 A EP92104008 A EP 92104008A EP 92104008 A EP92104008 A EP 92104008A EP 0505812 B1 EP0505812 B1 EP 0505812B1
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sub
stage
pressure
work
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German (de)
French (fr)
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EP0505812A1 (en
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Wilhelm Dipl.-Ing. Rohde (Fh)
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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
    • F25J3/04248—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
    • F25J3/04006—Providing pressurised feed air or process streams within or from the air fractionation unit
    • F25J3/04012—Providing pressurised feed air or process streams within or from the air fractionation unit by compression of warm gaseous streams; details of intake or interstage cooling
    • F25J3/04018—Providing pressurised feed air or process streams within or from the air fractionation unit by compression of warm gaseous streams; details of intake or interstage cooling of main feed air
    • 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
    • F25J3/04006—Providing pressurised feed air or process streams within or from the air fractionation unit
    • F25J3/04012—Providing pressurised feed air or process streams within or from the air fractionation unit by compression of warm gaseous streams; details of intake or interstage cooling
    • F25J3/04024—Providing pressurised feed air or process streams within or from the air fractionation unit by compression of warm gaseous streams; details of intake or interstage cooling of purified feed air, so-called boosted air
    • 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
    • F25J3/04006—Providing pressurised feed air or process streams within or from the air fractionation unit
    • F25J3/04078—Providing pressurised feed air or process streams within or from the air fractionation unit providing pressurized products by liquid compression and vaporisation with cold recovery, i.e. so-called internal compression
    • F25J3/0409—Providing pressurised feed air or process streams within or from the air fractionation unit providing pressurized products by liquid compression and vaporisation with cold recovery, i.e. so-called internal compression of oxygen
    • 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
    • F25J3/04006—Providing pressurised feed air or process streams within or from the air fractionation unit
    • F25J3/04078—Providing pressurised feed air or process streams within or from the air fractionation unit providing pressurized products by liquid compression and vaporisation with cold recovery, i.e. so-called internal compression
    • F25J3/04103—Providing pressurised feed air or process streams within or from the air fractionation unit providing pressurized products by liquid compression and vaporisation with cold recovery, i.e. so-called internal compression using solely hydrostatic liquid head
    • 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
    • F25J3/04006—Providing pressurised feed air or process streams within or from the air fractionation unit
    • F25J3/04109—Arrangements of compressors and /or their drivers
    • F25J3/04115—Arrangements of compressors and /or their drivers characterised by the type of prime driver, e.g. hot gas expander
    • 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
    • F25J3/04151—Purification and (pre-)cooling of the feed air; recuperative heat-exchange with product streams
    • F25J3/04157—Afterstage cooling and so-called "pre-cooling" of the feed air upstream the air purification unit and main heat exchange line
    • 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
    • F25J3/04151—Purification and (pre-)cooling of the feed air; recuperative heat-exchange with product streams
    • F25J3/04187—Cooling of the purified feed air by recuperative heat-exchange; Heat-exchange with product streams
    • F25J3/04193—Division of the main heat exchange line in consecutive sections having different functions
    • 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
    • F25J2215/00—Processes characterised by the type or other details of the product stream
    • F25J2215/50—Oxygen or special cases, e.g. isotope-mixtures or low purity O2
    • 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
    • F25J2240/00—Processes or apparatus involving steps for expanding of process streams
    • F25J2240/02—Expansion of a process fluid in a work-extracting turbine (i.e. isentropic expansion), e.g. of the feed stream
    • F25J2240/10—Expansion of a process fluid in a work-extracting turbine (i.e. isentropic expansion), e.g. of the feed stream the fluid being air
    • 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
    • F25J2245/00—Processes or apparatus involving steps for recycling of process streams
    • F25J2245/40—Processes or apparatus involving steps for recycling of process streams the recycled stream being air
    • 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
    • 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
    • Y10S62/939—Partial feed stream expansion, air

Definitions

  • the invention relates to a process for the low-temperature extraction of air, in which feed air is compressed, cleaned, cooled and divided into several partial streams into the pressure stage and into the low-pressure stage of a two-stage rectification device, the feed air being brought to approximately the pressure stage pressure in a first compressor stage Cleaning stage is cleaned by adsorption and then divided into a first and a second partial stream, the first partial stream is fed to the pressure stage and the second partial stream is expanded while performing work and is fed to the low-pressure stage, the work obtained in the expansion of the second partial stream to compress a process stream, in particular air is used.
  • DE-A-3643359 shows such a method, in which both partial flows are fed downstream of the cleaning stage to a main heat exchanger, the warm end of which has approximately ambient temperature.
  • the second partial flow is cooled to a lower temperature in the main heat exchanger before it is relieved of pressure.
  • the work gained during the expansion is used exclusively to compress the second partial flow.
  • One of the relevant methods of GB-A-1520103 is to bring the total air upstream of the cleaning stage from ambient temperature into indirect heat exchange with the total air downstream of the cleaning stage .
  • the invention is therefore based on the object of specifying a method, which has a high efficiency and in particular a more cost effective air purification.
  • This object is achieved in that the second partial stream is heated to above ambient temperature in indirect heat exchange against compressed feed air before the work-relieving expansion and in that the process stream, for the compression of which work obtained in the expansion of the second partial stream is used, is not equal to the second partial stream .
  • the process according to the invention makes it possible to treat the entire feed air in a single cleaning stage, namely under pressure stage pressure.
  • the investment costs and the high operating costs for an additional low-pressure cleaning stage are eliminated.
  • the excess compression energy that is put into the second partial flow can be recovered in a turbine partly as mechanical work and partly converted into cold.
  • the work is usually given completely and directly to a compressor by mechanical coupling, but additionally or alternatively, a generator can also be driven.
  • a generator can also be driven.
  • the second partial flow is previously warmed to above ambient temperature . In this way, heat can be extracted from compressed compressed air cheaply.
  • a product or an intermediate product flow can flow through the compressor driven by the turbine. In general, it is most convenient to use the work gained from work relaxation to compress feed air.
  • cooling can be generated in the process by branching off a third partial stream downstream of the adsorption, post-compressing in a second compressor stage, then cooling, relieving work and feeding it into the low-pressure stage, with work obtained during the work-relieving expansion of the third partial stream to post-compress the third Partial flow is used in the second compressor stage. In this case, pressure that is not required is also used to generate process cooling.
  • the invention provides two variants for the transfer of work and cold:
  • the feed air must be pre-cooled anyway. It generally leaves a cooler operated with cooling water of approximately 25 ° C. and a temperature of approximately 35 ° C. and must be brought to approximately 10 ° C. to 15 ° C. for the adsorption in the cleaning stage. This is generally accomplished by an external refrigeration system or by cold cooling water taken from an evaporative cooler operated with dry nitrogen. This pre-cooling can now be at least partially carried out by the cleaned second partial flow, so that the costs for the refrigeration system are reduced or the nitrogen is available for other tasks.
  • work gained in the work-relieving expansion of the second partial flow is used in a third compressor stage for post-compression of the third partial flow.
  • This third compressor stage is preferably connected upstream of the second compressor stage and serves to increase the pressure difference during the expansion of the third partial flow. It is also expedient if, in addition or as an alternative, a fourth partial flow is branched off downstream of the cleaning stage, subsequently compressed in a fourth compressor stage, then cooled, decompressed and fed into the pressure stage, with work obtained in the work-relieving relaxation of the second partial flow to recompress the fourth partial flow in the fourth compressor stage is used.
  • the relief of the fourth partial flow is generally brought about by a throttle valve.
  • third and the fourth partial flow are post-compressed in a common third compressor stage.
  • the third and fourth compressor stages are implemented as a single machine relatively inexpensively.
  • a second type of transfer of the heat to the second partial stream is that the heating of the second partial stream prior to its expansion by indirect heat exchange with the third and / or fourth partial stream after the compression in the third or fourth compressor stage is carried out.
  • This measure makes it possible to achieve a particularly favorable adaptation of the flows to the inlet temperature of the main heat exchanger by cooling the partial flow or streams that are subsequently compressed.
  • the cold available before the second partial flow enters the expansion turbine is used particularly efficiently at this point.
  • Post-compression of the fourth partial flow above the pressure column pressure is particularly advantageous if oxygen is to be obtained under increased pressure in the process.
  • liquid oxygen is led out of the low-pressure stage, brought to pressure and evaporated in indirect heat exchange with the post-compressed fourth partial flow.
  • the part of the air available under a higher pressure column pressure is used here for an energetically favorable production of pressurized oxygen.
  • the oxygen is pressurized in liquid form (either by a pump or by utilizing a hydrostatic potential) and then evaporated under the increased pressure.
  • the high-pressure air condenses in counterflow to the evaporating oxygen and emits latent heat.
  • the indirect heat exchange is preferably carried out in the main heat exchanger block through which the other feed and product flows also flow.
  • the invention also relates to a device for the low-temperature extraction of air according to claim 11 .
  • air separation plants more than 100,000 Nm3 / h, preferably more than 200,000 Nm3 / h, most preferably between 200,000 and 400,000 Nm3 / h separation air
  • the advantages of the invention are particularly evident.
  • Use in the context of GUD (combined cycle) plants or plants for steel production (eg COREX process) is also advantageous.
  • FIGS. 1 and 2 show schematically in FIGS. 1 and 2.
  • the same reference numerals are used in both drawings for analog process steps.
  • atmospheric air is drawn in via a line 1 from a first compressor stage 2 and compressed to a pressure of 5 to 10 bar, preferably about 5.65 bar, and cooled to 5 to 25 ° C., preferably about 12 ° C. and freed of impurities such as water, carbon dioxide and hydrocarbons in a cleaning stage 4 filled with a molecular sieve.
  • the feed air is branched into a first partial flow 101 and a second partial flow 102.
  • the first partial stream 101 is cooled in the main heat exchanger 5 against product streams and fed into the pressure stage 7 of a conventional two-stage rectification column 6.
  • Gaseous oxygen 9 and gaseous nitrogen 10 are taken from the low-pressure stage 8 (working pressure 1.2 to 1.6 bar, preferably about 1.3 bar) and heated in the main heat exchanger 5 to about ambient temperature.
  • the nitrogen can be used to regenerate the molecular sieve of cleaning stage 4 (line 11) and / or also for other purposes, for example for cooling cooling water in an evaporative cooler, via line 12.
  • the second partial flow 102 is heated in a heat exchanger 3 against the compressed feed air, expanded in a turbine 13, cooled and blown into the low-pressure stage 8.
  • the feed air flow is additionally cooled between heat exchanger 3 and cleaning stage 4 (not shown in the drawing), for example by indirect heat exchange with water cooled by evaporative cooling.
  • a third partial flow 103 is also branched off downstream of the cleaning stage 4, further compressed in a second compressor 14, cooled to an average temperature in the main heat exchanger 5 and then expanded in a turbine 15 for generating cooling.
  • the work obtained when releasing the partial flow is mechanically transferred to the second compressor 14.
  • the relaxed third partial flow 103 is introduced into the low-pressure stage 8 together with the relaxed and cooled second partial flow 102.
  • FIG. 2 shows an exemplary embodiment for a second variant of the method.
  • the second partial flow is branched off at a branch point 21 from the first partial flow 101, warmed in the heat exchanger 3 'and relaxed in the turbine 13'.
  • the work obtained is transferred to a third compressor 16.
  • the third partial flow is compressed in the third compressor to a pressure of at least 15 bar, preferably about 20 to 50 bar, and then cooled in the heat exchanger 3 'against the second partial flow 102 before it relaxes, before the second secondary compressor 14 coupled to the turbine 15 reached.
  • a fourth partial flow 104 is branched off from the third partial flow (22), cooled in the main heat exchanger 5 and throttled into the pressure stage 7.
  • oxygen is evaporated, which was taken from line 9 of the low-pressure stage and brought to a pressure of at least 4 bar, preferably 20 to 100 bar, in a pump 17.
  • the high pressure air in the fourth partial flow condenses almost completely during the heat exchange and is fed into the pressure stage 7 above the first partial flow 101.
  • the process with direct feed of feed air to the low pressure stage proves to be economically advantageous if a purity of 85 to 98% is to be achieved in the product oxygen (lines 23 and 24 in the exemplary embodiment). If, for example, an oxygen purity of 96% is desired, up to 35% of the feed air can be fed directly into the low-pressure stage via the second and third partial streams 102, 103 without significantly reducing the oxygen yield.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Health & Medical Sciences (AREA)
  • Emergency Medicine (AREA)
  • Separation By Low-Temperature Treatments (AREA)
  • Separation Of Gases By Adsorption (AREA)
  • Transition And Organic Metals Composition Catalysts For Addition Polymerization (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Solid-Sorbent Or Filter-Aiding Compositions (AREA)

Abstract

A low-temperature air separation process is described, in particular for producing oxygen of medium purity. In the process, the entire feed air (1) is compressed in a first compressor stage (2) and purified by adsorption (4). A first part-stream (101) of the air is fed into the pressure stage (7) of a two-stage rectification column (6). A second part-stream is fed directly to the low-pressure stage (8). According to the invention, it is separated off from the remaining feed air after the adsorption (4), warmed (3) by exchange with compressed feed air and expanded, producing work (13). The work thus recovered is used at least partially for compressing (2) the feed air. <IMAGE>

Description

Die Erfindung betrifft ein Verfahren zur Tieftemperaturzeriegung von Luft, bei dem Einsatzluft verdichtet, gereinigt, abgekühlt und in mehrere Teilströme aufgeteilt in die Druckstufe und in die Niederdruckstufe einer zweistufigen Rektifiziereinrichtung eingeleitet wird, wobei die Einsatzluft in einer ersten Verdichterstufe auf etwa Druckstufendruck gebracht, in einer Reinigungsstufe durch Adsorption gereinigt und anschließend in einen ersten und in einen zweiten Teilstrom aufgeteilt wird, der erste Teilstrom der Druckstufe zugeführt wird und der zweite Teilstrom arbeitsleistend entspannt und der Niederdruckstufe zugeleitet wird, wobei bei der Entspannung des zweiten Teilstroms gewonnene Arbeit zur Verdichtung eines Prozeßstroms, insbesondere von Einsatzluft verwendet wird. The invention relates to a process for the low-temperature extraction of air, in which feed air is compressed, cleaned, cooled and divided into several partial streams into the pressure stage and into the low-pressure stage of a two-stage rectification device, the feed air being brought to approximately the pressure stage pressure in a first compressor stage Cleaning stage is cleaned by adsorption and then divided into a first and a second partial stream, the first partial stream is fed to the pressure stage and the second partial stream is expanded while performing work and is fed to the low-pressure stage, the work obtained in the expansion of the second partial stream to compress a process stream, in particular air is used.

Die DE-A-3643359 zeigt ein derartiges Verfahren, bei dem beide Teilströme stromabwärts der Reinigungsstufe einem Hauptwärmetauscher zugeführt werden, dessen warmes Ende etwa Umgebungstemperatur aufweist. Der zweite Teilstrom wird in dem Hauptwärmetauscher vor seiner arbeitsleistenden Entspannung auf eine niedrigere Temperatur abgekühlt. Die bei der Entspannung gewonnene Arbeit wird ausschließlich zur Verdichtung des zweiten Teilstroms eingesetzt.DE-A-3643359 shows such a method, in which both partial flows are fed downstream of the cleaning stage to a main heat exchanger, the warm end of which has approximately ambient temperature. The second partial flow is cooled to a lower temperature in the main heat exchanger before it is relieved of pressure. The work gained during the expansion is used exclusively to compress the second partial flow.

Ein dem einschlägigen Verfahren der GB-A-1520103 wird die Gesamtluft stromaufwärts der Reinigungsstufe von Umgebungstemperatur aus in indirektem Wärmetausch mit der Gesamtluft stromabwärts der Reinigungsstufe gebracht. One of the relevant methods of GB-A-1520103 is to bring the total air upstream of the cleaning stage from ambient temperature into indirect heat exchange with the total air downstream of the cleaning stage .

Ein ähnliches Verfahren ist aus der EP-A 0 342 436 bekannt. Hier wird die Einsatzluft zunächst nur auf Niederdruckstufendruck komprimiert und auf dem mittleren Druckniveau in einen ersten und in einen zweiten Teilstrom aufgeteilt. Lediglich der erste Teilstrom, der teilweise in die Drucksäule eingespeist wird, wird weiter verdichtet. Dieser Prozeß bewirkt zwar eine sehr wirtschaftliche Verwendung der Kompressionsenergie. Allerdings ist man gezwungen, die Entfernung von Kohlendioxid, Kohlenwasserstoffen und Wasser aus dem zweiten Teilstrom in einer eigenen Reinigungsstufe, in der Regel einer Molsiebstation, vorzunehmen. Durch den niedrigen Druck benötigt dieses Molsieb hohe Mengen an Regeneriergas. Diese stehen dann für andere Zwecke nicht mehr zur Verfügung, insbesondere nicht für eine kostengünstige Verdunstungskühlung des für die Vorkühlung der Luft benötigten Kühlwassers.A similar process is known from EP-A 0 342 436. Here, the feed air is initially only compressed to low-pressure stage pressure and divided into a first and a second partial flow at the medium pressure level. Only the first partial flow, which is partly fed into the pressure column, is further compressed. This process causes a very economical use of the compression energy. However, one is forced to remove carbon dioxide, hydrocarbons and water from the second partial stream in a separate cleaning stage, usually a molecular sieve station. Due to the low pressure, this molecular sieve requires large amounts of regeneration gas. These are then no longer available for other purposes, in particular not for cost-effective evaporative cooling of the cooling water required for the pre-cooling of the air.

Der Erfindung liegt daher die Aufgabe zugrunde, ein Verfahren anzugeben, das eine hohe Wirtschaftlichkeit und insbesondere eine kostengünstigere Luftreinigung aufweist.The invention is therefore based on the object of specifying a method, which has a high efficiency and in particular a more cost effective air purification.

Diese Aufgabe wird dadurch gelöst, daß der zweite Teilstrom vor der arbeitsleistenden Entspannung in indirektem Wärmetausch gegen verdichtete Einsatzluft auf über Umgebungstemperatur angewärmt wird und daß der Prozeßstrom, zu dessen Verdichtung bei der Entspannung des zweiten Teilstroms gewonnene Arbeit verwendet wird, nicht gleich dem zweiten Teilstrom ist.This object is achieved in that the second partial stream is heated to above ambient temperature in indirect heat exchange against compressed feed air before the work-relieving expansion and in that the process stream, for the compression of which work obtained in the expansion of the second partial stream is used, is not equal to the second partial stream .

Durch die erfindungsgemäße Verfahrensführung ist es möglich, die gesamte Einsatzluft in einer einzigen Reinigungsstufe zu behandeln, und zwar unter Druckstufendruck. Es entfallen die Investitionskosten und der hohe Betriebsaufwand für eine zusätzliche Niederdruck-Reinigungsstufe. Die überschüssige Kompressionsenergie, die in den zweiten Teilstrom gesteckt wird, kann in einer Turbine teils als mechanische Arbeit zurückgewonnen, teils in Kälte umgesetzt werden.The process according to the invention makes it possible to treat the entire feed air in a single cleaning stage, namely under pressure stage pressure. The investment costs and the high operating costs for an additional low-pressure cleaning stage are eliminated. The excess compression energy that is put into the second partial flow can be recovered in a turbine partly as mechanical work and partly converted into cold.

Die Arbeit wird in der Regel vollständig und direkt durch mechanische Kopplung an einen Verdichter abgegeben, zusätzlich oder alternativ kann jedoch auch ein Generator angetrieben werden. Um die arbeitsleistende Entspannung unter günstigen Bedingungen durchzuführen, wird der zweite Teilstrom vorher auf über Umgebungstemperatur angewärmt. Dabei kann verdichteter Einsatzluft günstig Wärme entzogen werden.The work is usually given completely and directly to a compressor by mechanical coupling, but additionally or alternatively, a generator can also be driven. In order to carry out the relaxation work under favorable conditions, the second partial flow is previously warmed to above ambient temperature . In this way, heat can be extracted from compressed compressed air cheaply.

Durch den von der Turbine angetriebenen Verdichter kann beispielsweise ein Produkt- oder einer Zwischenproduktstrom fließen. Im allgemeinen ist die Verwendung der bei der arbeitsleistenden Entspannung gewonnenen Arbeit zur Verdichtung von Einsatzluft am günstigsten.A product or an intermediate product flow can flow through the compressor driven by the turbine. In general, it is most convenient to use the work gained from work relaxation to compress feed air.

Zusätzlich kann in dem Verfahren Kälte erzeugt werden, indem stromabwärts der Adsorption ein dritter Teilstrom abgezweigt, in einer zweiten Verdichterstufe nachverdichtet, anschließend abgekühlt, arbeitsleistend entspannt und in die Niederdruckstufe eingespeist wird, wobei bei der arbeitsleistenden Entspannung des dritten Teilstroms gewonnene Arbeit zur Nachverdichtung des dritten Teilstroms in der zweiten Verdichterstufe eingesetzt wird. Hierbei wird ebenfalls nicht benötigter Druck für die Erzeugung von Verfahrenkälte ausgenutzt.In addition, cooling can be generated in the process by branching off a third partial stream downstream of the adsorption, post-compressing in a second compressor stage, then cooling, relieving work and feeding it into the low-pressure stage, with work obtained during the work-relieving expansion of the third partial stream to post-compress the third Partial flow is used in the second compressor stage. In this case, pressure that is not required is also used to generate process cooling.

Für die Übertragung von Arbeit und Kälte stellt die Erfindung zwei Varianten zur Verfügung:The invention provides two variants for the transfer of work and cold:

Zum einen kann bei der arbeitsleistenden Entspannung des zweiten Teilstroms gewonnene Arbeit zum Antrieb der ersten Verdichterstufe eingesetzt werden. Da diese Arbeit selbstverständlich nicht für den Antrieb des Luftverdichters ausreicht, muß die Welle, die in der Regel Entspannungsturbine und erste Verdichterstufe verbindet, zusätzlich durch einen Motor angetrieben werden.On the one hand, work gained during the work-relieving expansion of the second partial flow can be used to drive the first compressor stage. Since this work is of course not sufficient to drive the air compressor, the shaft, which usually connects the expansion turbine and the first compressor stage, must also be driven by a motor.

Dabei ist es vorteilhaft, wenn die Anwärmung des zweiten Teilstroms vor seiner Entspannung durch indirekten Wärmetausch mit Einsatzluft hinter der ersten Verdichterstufe und vor der Reinigungsstufe durchgeführt wird.It is advantageous if the heating of the second partial flow is carried out before it is relaxed by indirect heat exchange with feed air after the first compressor stage and before the cleaning stage.

An dieser Stelle muß die Einsatzluft ohnehin vorgekühlt werden. Sie verläßt in der Regel einen mit Kühlwasser von etwa 25°C betriebenen Kühler mit einer Temperatur von ca. 35°C und muß für die Adsorption in der Reinigungsstufe auf etwa 10°C bis 15°C gebracht werden. Dies wird im allgemeinen durch eine externe Kälteanlage oder durch kaltes Kühlwasser bewerkstelligt, das einem mit trockenem Stickstoff betriebenen Verdunstungskühler entnommen wird. Diese Vorkühlung kann nun zumindest teilweise von dem gereinigten zweiten Teilstrom übernommen werden, so daß die Kosten für die Kälteanlage verringert werden beziehungsweise der Stickstoff für andere Aufgaben zur Verfügung steht.At this point, the feed air must be pre-cooled anyway. It generally leaves a cooler operated with cooling water of approximately 25 ° C. and a temperature of approximately 35 ° C. and must be brought to approximately 10 ° C. to 15 ° C. for the adsorption in the cleaning stage. This is generally accomplished by an external refrigeration system or by cold cooling water taken from an evaporative cooler operated with dry nitrogen. This pre-cooling can now be at least partially carried out by the cleaned second partial flow, so that the costs for the refrigeration system are reduced or the nitrogen is available for other tasks.

In einer zweiten Variante wird bei der arbeitsleistenden Entspannung des zweiten Teilstroms gewonnene Arbeit in einer dritten Verdichterstufe zur Nachverdichtung des dritten Teilstroms eingesetzt.In a second variant, work gained in the work-relieving expansion of the second partial flow is used in a third compressor stage for post-compression of the third partial flow.

Diese dritte Verdichterstufe ist vorzugsweise der zweiten Verdichterstufe vorgeschaltet und dient zur Erhöhung der Druckdifferenz bei der Entspannung des dritten Teilstroms. Günstig ist es außerdem, wenn stromabwärts der Reinigungsstufe zusätzlich oder alternativ ein vierter Teilstrom abgezweigt, in einer vierten Verdichterstufe nachverdichtet, anschließend abgekühlt, entspannt und in die Druckstufe eingespeist wird, wobei bei der arbeitsleistenden Entspannung des zweiten Teilstroms gewonnene Arbeit zur Nachverdichtung des vierten Teilstroms in der vierten Verdichterstufe eingesetzt wird. Die Entspannung des vierten Teilstromes wird im allgemeinen durch ein Drosselventil bewerkstelligt.This third compressor stage is preferably connected upstream of the second compressor stage and serves to increase the pressure difference during the expansion of the third partial flow. It is also expedient if, in addition or as an alternative, a fourth partial flow is branched off downstream of the cleaning stage, subsequently compressed in a fourth compressor stage, then cooled, decompressed and fed into the pressure stage, with work obtained in the work-relieving relaxation of the second partial flow to recompress the fourth partial flow in the fourth compressor stage is used. The relief of the fourth partial flow is generally brought about by a throttle valve.

Die Numerierung der Verdichterstufen ist hier zu ihrer klaren Unterscheidung eingeführt, sie bedeutet nicht, daß bei Existenz der vierten Verdichterstufe auch notwendigerweise die oben erwähnte zweite oder dritte Verdichterstufe vorhanden sein müssen.The numbering of the compressor stages is introduced here to clearly differentiate them, it does not mean that if the fourth compressor stage exists, the above-mentioned second or third compressor stage must also necessarily be present.

Es hat sich jedoch als vorteilhaft erwiesen, wenn der dritte und der vierte Teilstrom in einer gemeinsamen dritten Verdichterstufe nachverdichtet werden. Dritte und vierte Verdichterstufe werden dabei als eine einzige Maschine relativ kostengünstig realisiert.However, it has proven to be advantageous if the third and the fourth partial flow are post-compressed in a common third compressor stage. The third and fourth compressor stages are implemented as a single machine relatively inexpensively.

Eine zweite Art der Übertragung der Wärme auf den unter hohem Druck stehenden zweiten Teilstrom besteht nach einem weiteren Aspekt der Erfindung darin, daß die Anwärmung des zweiten Teilstroms vor seiner Entspannung durch indirekten Wärmetausch mit dem dritten und/oder vierten Teilstrom nach der Nachverdichtung in der dritten beziehungsweise vierten Verdichterstufe durchgeführt wird.According to a further aspect of the invention, a second type of transfer of the heat to the second partial stream, which is under high pressure, is that the heating of the second partial stream prior to its expansion by indirect heat exchange with the third and / or fourth partial stream after the compression in the third or fourth compressor stage is carried out.

Durch diese Maßnahme läßt sich eine besonders günstige Anpassung der Ströme an die Eintrittstemperatur des Hauptwärmetauschers erreichen, indem der oder die nachverdichteten Teilströme abgekühlt werden. Die vor Eintritt des zweiten Teilstroms in die Entspannungsturbine zur Verfügung stehende Kälte wird an dieser Stelle besonders effizient eingesetzt.This measure makes it possible to achieve a particularly favorable adaptation of the flows to the inlet temperature of the main heat exchanger by cooling the partial flow or streams that are subsequently compressed. The cold available before the second partial flow enters the expansion turbine is used particularly efficiently at this point.

Eine Nachverdichtung des vierten Teilstroms über den Drucksäulendruck hinaus ist vor allem dann günstig, wenn bei dem Verfahren Sauerstoff unter erhöhtem Druck gewonnen werden soll. Hierbei wird in vorteilhafter Weiterbildung des erfinderischen Gedankens flüssiger Sauerstoff aus der Niederdruckstufe herausgeführt, auf Druck gebracht und in indirektem Wärmeaustausch mit dem nachverdichteten vierten Teilstrom verdampft.Post-compression of the fourth partial flow above the pressure column pressure is particularly advantageous if oxygen is to be obtained under increased pressure in the process. In an advantageous development of the inventive concept, liquid oxygen is led out of the low-pressure stage, brought to pressure and evaporated in indirect heat exchange with the post-compressed fourth partial flow.

Die unter höherem als Drucksäulendruck zur Verfügung stehende Teilmenge der Luft wird hier für eine energetisch günstige Herstellung von Drucksauerstoff verwendet. Der Sauerstoff wird in flüssiger Form auf Druck gebracht (entweder durch eine Pumpe oder durch Ausnützung eines hydrostatischen Potentials) und anschließend unter dem erhöhten Druck verdampft. Die Hochdruckluft kondensiert im Gegenstrom zum verdampfenden Sauerstoff und gibt dabei latente Wärme ab. Der indirekte Wärmetausch wird vorzugsweise in dem Hauptwärmetauscherblock vorgenommen, den auch die anderen Einsatz- und Produktströme durchströmen.The part of the air available under a higher pressure column pressure is used here for an energetically favorable production of pressurized oxygen. The oxygen is pressurized in liquid form (either by a pump or by utilizing a hydrostatic potential) and then evaporated under the increased pressure. The high-pressure air condenses in counterflow to the evaporating oxygen and emits latent heat. The indirect heat exchange is preferably carried out in the main heat exchanger block through which the other feed and product flows also flow.

Dabei ist es günstig, wenn der partiell kondensierte vierte Teilstrom anschließend oberhalb des ersten Teilstroms in die Druckstufe eingeleitet wird.It is advantageous if the partially condensed fourth partial flow is then introduced into the pressure stage above the first partial flow.

In der Regel kondensiert bei dem Wärmetausch mit Drucksauerstoff der größte Teil der Hochdruckluft, so daß ein gewisser Vortrenneffekt ausgenutzt werden kann, indem das Kondensat mindestens einen theoretischen Boden, vorzugsweise etwa vier bis acht theoretische Böden oberhalb der übrigen Drucksäulenluft eingespeist wird.As a rule, most of the high-pressure air condenses during the heat exchange with pressurized oxygen, so that a certain pre-separation effect can be exploited by feeding the condensate at least one theoretical plate, preferably about four to eight theoretical plates, above the remaining pressure column air.

Die Erfindung betrifft außerdem eine Vorrichtung zur Tieftemperaturzeriegungvon Luft nach Patentanspruch 11. The invention also relates to a device for the low-temperature extraction of air according to claim 11 .

Besonders vorteilhaft ist die Anwendung des erfindungsgemäßen Verfahrens und/oder der erfindungsgemäßen Vorrichtung zur Gewinnung von Sauerstoff geringer Reinheit.The use of the method according to the invention and / or the device according to the invention for obtaining oxygen of low purity is particularly advantageous.

Hiermit sind Sauerstoffreinheiten unterhalb von 99%, vorzugsweise zwischen 85% und 98% (bezogen auf das Volumen) gemeint. Bei Luftzerlegungsanlagen (mehr als 100.000 Nm³/h, vorzugsweise mehr als 200.000 Nm³/h, höchst vorzugsweise zwischen 200.000 und 400.000 Nm³/h Zerlegungsluft) kommen die Vorteile der Erfindung besonders deutlich zum Tragen. Vorteilhaft ist auch ein Einsatz im Rahmen von GUD-(combined cycle)-Anlagen oder von Anlagen zur Stahlgewinnung (z.B. COREX-Verfahren).This means oxygen purities below 99%, preferably between 85% and 98% (by volume). In air separation plants (more than 100,000 Nm³ / h, preferably more than 200,000 Nm³ / h, most preferably between 200,000 and 400,000 Nm³ / h separation air), the advantages of the invention are particularly evident. Use in the context of GUD (combined cycle) plants or plants for steel production (eg COREX process) is also advantageous.

Im folgenden werden die Erfindung und weitere Ausbildungen der Erfindung anhand zweier Ausführungsbeispiele näher erläutert, die in den Figuren 1 und 2 schematisch dargestellt ist. Soweit wie möglich werden in beiden Zeichnungen für analoge Verfahrensschritte dieselben Bezugszeichen verwendet.The invention and further developments of the invention are explained in more detail below with reference to two exemplary embodiments, which are shown schematically in FIGS. 1 and 2. As far as possible, the same reference numerals are used in both drawings for analog process steps.

Gemäß dem Verfahrensschema der Figur 1 wird atmosphärische Luft über eine Leitung 1 von einer ersten Verdichterstufe 2 angesaugt und auf einen Druck von 5 bis 10 bar vorzugsweise etwa 5,65 bar, komprimiert, auf 5 bis 25°C, vorzugsweise etwa 12°C abgekühlt und in einer mit einem Molsieb gefüllten Reinigungsstufe 4 von Verunreinigungen wie beispielsweise Wasser, Kohlendioxid und Kohlenwasserstoffen befreit.According to the process diagram of FIG. 1, atmospheric air is drawn in via a line 1 from a first compressor stage 2 and compressed to a pressure of 5 to 10 bar, preferably about 5.65 bar, and cooled to 5 to 25 ° C., preferably about 12 ° C. and freed of impurities such as water, carbon dioxide and hydrocarbons in a cleaning stage 4 filled with a molecular sieve.

Unmittelbar hinter der Reinigungsstufe 4 wird die Einsatzluft in einen ersten Teilstrom 101 und in einen zweiten Teilstrom 102 verzweigt. Der erste Teilstrom 101 wird im Hauptwärmetauscher 5 gegen Produktströme abgekühlt und in die Druckstufe 7 einer gewöhnlichen zweistufigen Rektifiziersäule 6 eingespeist. Als Produkte werden der Niederdruckstufe 8 (Arbeitsdruck 1,2 bis 1,6 bar, vorzugsweise etwa 1,3 bar) gasförmiger Sauerstoff 9 und gasförmiger Stickstoff 10 entnommen und im Hauptwärmetauscher 5 auf etwa Umgebungstemperatur angewärmt. Der Stickstoff kann zur Regenerierung des Molsiebs der Reinigungsstufe 4 eingesetzt (Leitung 11) und/oder auch für andere Zwecke, beispielsweise zur Abkühlung von Kühlwasser in einem Verdunstungskühler über Leitung 12 abgezogen werden.Immediately after the cleaning stage 4, the feed air is branched into a first partial flow 101 and a second partial flow 102. The first partial stream 101 is cooled in the main heat exchanger 5 against product streams and fed into the pressure stage 7 of a conventional two-stage rectification column 6. Gaseous oxygen 9 and gaseous nitrogen 10 are taken from the low-pressure stage 8 (working pressure 1.2 to 1.6 bar, preferably about 1.3 bar) and heated in the main heat exchanger 5 to about ambient temperature. The nitrogen can be used to regenerate the molecular sieve of cleaning stage 4 (line 11) and / or also for other purposes, for example for cooling cooling water in an evaporative cooler, via line 12.

Der zweite Teilstrom 102 wird in einem Wärmetauscher 3 gegen die verdichtete Einsatzluft angewärmt, in einer Turbine 13 entspannt, abgekühlt und in die Niederdruckstufe 8 eingeblasen. Der Einsatzluftstrom wird zwischen Wärmetauscher 3 und Reinigungsstufe 4 zusätzlich abgekühlt (in der Zeichnung nicht dargestellt), beispielsweise durch indirekten Wärmetausch mit durch Verdunstungskühlung abgekühltem Wasser.The second partial flow 102 is heated in a heat exchanger 3 against the compressed feed air, expanded in a turbine 13, cooled and blown into the low-pressure stage 8. The feed air flow is additionally cooled between heat exchanger 3 and cleaning stage 4 (not shown in the drawing), for example by indirect heat exchange with water cooled by evaporative cooling.

Ein dritter Teilstrom 103 wird ebenfalls stromabwärts der Reinigungsstufe 4 abgezweigt, in einem zweiten Verdichter 14 weiterverdichtet, im Hauptwärmetauscher 5 auf eine mittlere Temperatur abgekühlt und danach in einer Turbine 15 zur Kälteerzeugung entspannt. Die beim Entspannen des Teilstroms gewonnene Arbeit wird mechanisch auf den zweiten Verdichter 14 übertragen. Der entspannte dritte Teilstrom 103 wird gemeinsam mit dem entspannten und abgekühlten zweiten Teilstrom 102 in die Niederdruckstufe 8 eingeführt.A third partial flow 103 is also branched off downstream of the cleaning stage 4, further compressed in a second compressor 14, cooled to an average temperature in the main heat exchanger 5 and then expanded in a turbine 15 for generating cooling. The work obtained when releasing the partial flow is mechanically transferred to the second compressor 14. The relaxed third partial flow 103 is introduced into the low-pressure stage 8 together with the relaxed and cooled second partial flow 102.

Die Figur 2 zeigt ein Ausführungsbeispiel für eine zweite Variante des Verfahrens. Der zweite Teilstrom wird hier an einem Verzweigungspunkt 21 vom ersten Teilstrom 101 abgezweigt, im Wärmetauscher 3′ angewärmt und in der Turbine 13′ entspannt. Die dabei gewonnene Arbeit wird auf einen dritten Verdichter 16 übertragen.FIG. 2 shows an exemplary embodiment for a second variant of the method. The second partial flow is branched off at a branch point 21 from the first partial flow 101, warmed in the heat exchanger 3 'and relaxed in the turbine 13'. The work obtained is transferred to a third compressor 16.

Der dritte Teilstrom wird im dritten Verdichter auf einen Druck von mindestens 15 bar, vorzugsweise etwa 20 bis 50 bar, komprimiert und anschließend im Wärmetauscher 3′ gegen den zweiten Teilstrom 102 vor dessen Entspannung abgekühlt, bevor er den mit der Turbine 15 gekoppelten zweiten Nachverdichter 14 erreicht.The third partial flow is compressed in the third compressor to a pressure of at least 15 bar, preferably about 20 to 50 bar, and then cooled in the heat exchanger 3 'against the second partial flow 102 before it relaxes, before the second secondary compressor 14 coupled to the turbine 15 reached.

Hinter der dritten Verdichterstufe 16 und dem Wärmetauscher 3′ wird aus dem dritten Teilstrom ein vierter Teilstrom 104 abgezweigt (22), im Hauptwärmetauscher 5 abgekühlt und in die Druckstufe 7 eingedrosselt. Im Gegenstrom hierzu wird Sauerstoff verdampft, der über Leitung 9 der Niederdruckstufe entnommen und in einer Pumpe 17 auf einen Druck von mindestens 4 bar, vorzugsweise 20 bis 100 bar, gebracht wurde. Die Hochdruckluft im vierten Teilstrom kondensiert bei dem Wärmeaustausch fast vollständig und wird oberhalb des ersten Teilstroms 101 in die Druckstufe 7 eingespeist.After the third compressor stage 16 and the heat exchanger 3 ', a fourth partial flow 104 is branched off from the third partial flow (22), cooled in the main heat exchanger 5 and throttled into the pressure stage 7. In countercurrent to this, oxygen is evaporated, which was taken from line 9 of the low-pressure stage and brought to a pressure of at least 4 bar, preferably 20 to 100 bar, in a pump 17. The high pressure air in the fourth partial flow condenses almost completely during the heat exchange and is fed into the pressure stage 7 above the first partial flow 101.

Das Verfahren mit Direkteinspeisung von Einsatzluft in die Niederdruckstufe erweist sich als wirtschaftlich günstig, wenn beim Produktsauerstoff (Leitungen 23 und 24 im Ausführungsbeispiel) eine Reinheit von 85 bis 98% erzielt werden soll. Falls beispielsweise eine Sauerstoffreinheit von 96% gewünscht ist, können bis zu 35% der Einsatzluft über den zweiten und dritten Teilstrom 102, 103 direkt in die Niederdruckstufe eingespeist werden, ohne die Sauerstoffausbeute merklich zu verringern.The process with direct feed of feed air to the low pressure stage proves to be economically advantageous if a purity of 85 to 98% is to be achieved in the product oxygen (lines 23 and 24 in the exemplary embodiment). If, for example, an oxygen purity of 96% is desired, up to 35% of the feed air can be fed directly into the low-pressure stage via the second and third partial streams 102, 103 without significantly reducing the oxygen yield.

Claims (12)

  1. Process for the low-temperature separation of air, in the course of which feed air (1) is compressed (2), purified (4), cooled (5) and, divided into a plurality of sub-streams, is introduced into the pressure stage (7) and into the low-pressure stage (8) of a two-stage rectifying appliance (6),
    - the feed air (1) being brought, in a first compressor stage (2), to approximately the pressure stage pressure, being purified by adsorption in a purification stage (4) and then being divided into a first (101) and into a second (102) sub-stream,
    - the first sub-stream (101) being fed to the pressure stage (7) and
    - the second sub-stream (102) being expanded in a manner so as to perform work (13, 13′) and being passed to the low-pressure stage (8),
    - work produced in the course of the expansion (13, 13′) of the second sub-stream (102) being employed for the compression (2, 16) of a process stream, in particular of feed air,
    characterized in that
    - the second sub-stream (102), prior to the work-performing expansion (13, 13′), is warmed up to above ambient temperature in indirect heat exchange (3, 3′) against compressed feed air, and in that
    - the process stream for whose compression (2, 16) work produced in the course of the expansion (13, 13′) of the second sub-stream (102) is employed is not identical with the second sub-stream (102).
  2. Process according to Claim 1, characterized in that a third sub-stream (103) is shunted off downstream of the adsorption (4), is subjected to secondary compression in a second compressor stage (14), is then cooled (5), is expanded (15) in a manner so as to perform work and is fed into the low-pressure stage (8), work produced during the work-performing expansion (15) of the third sub-stream being employed for the secondary compression of the third sub-stream in the second compressor stage (14).
  3. Process according to Claim 1 or 2, characterized in that work produced during the work-performing expansion (13) of the second sub-stream is employed to drive the first compressor stage (2).
  4. Process according to Claim 3, characterized in that the warming up of the second sub-stream prior to its expansion is carried out by indirect heat exchange (3) with feed air downstream of the first compressor stage (2) and upstream of the purification stage (4).
  5. Process according to Claim 2, characterized in that work produced during the work-performing expansion (13′) of the second sub-stream is employed in a third compressor stage (16) for the secondary compression of the third sub-stream.
  6. Process according to any one of Claims 1 to 5, characterized in that downstream of the purification stage (4) a fourth sub-stream (104) is shunted off, is subjected to secondary compression in a fourth compressor stage, is then cooled (5), expanded and fed into the pressure stage (7), work produced during the work-performing expansion (13′) of the second sub-stream being employed for the secondary compression of the fourth sub-stream in the fourth compressor stage (16).
  7. Process according to Claim 5 and 6, characterized in that the third (103) and fourth (104) sub-stream are subjected to secondary compression in a shared third compressor stage (16).
  8. Process according to any one of Claims 5 to 7, characterized in that the warming up of the second sub-stream (102) prior to its expansion is carried out by indirect heat exchange (3′) with the third and/or fourth sub-stream (104) after the secondary compression in the third (16) or fourth compressor stage, respectively.
  9. Process according to any one of Claims 5 to 8, characterized in that liquid oxygen is passed out (9) from the low-pressure stage (8), is pressurized (17) and is evaporated in indirect heat exchange (5) with the fourth sub-stream (104) subjected to secondary compression.
  10. Process according to Claim 9, characterized in that the fourth sub-stream (104) condenses at least partially in the course of the indirect heat exchange (5) with evaporating oxygen and is then introduced, above the first sub-stream (101), into the pressure stage (7).
  11. Apparatus for the low-temperature separation of air, comprising
    - a first compressor stage (2) for compressing feed air (1) to approximately pressure stage pressure, whose outlet is in flow communication with the inlet of a purification stage (4) which comprises an adsorption means,
    - a main heat exchanger (5),
    - a rectifying appliance (6) comprising a pressure column (7) and a low-pressure column (8),
    - a first sub-stream line (101) which runs from the outlet of the purification stage (4) to the pressure column (7),
    - a second sub-stream line (102) which runs from the outlet of the purification stage (4) via an expansion machine (13, 13′) to the low-pressure column (8), and
    - means for transferring the work produced in the expansion machine (13, 13′) to a means (2, 16) for compressing a process stream, in particular feed air,
    characterized in that
    - the second sub-stream line (102) upstream of the expansion machine (13, 13′) is run through a heat exchanger (3, 3′) for warming up to above ambient temperature in indirect heat exchange (3, 3′) against compressed feed air, and in that
    - the means (2, 16) for compressing a process stream and the expansion machine (13, 13′) are not connected to one another in such a way that the same process stream flows through both machines.
  12. Use of the process according to any one of Claims 1 to 10 and/or of the apparatus according to Claim 11 for producing low-purity oxygen.
EP92104008A 1991-03-26 1992-03-09 Low temperature air separation process Expired - Lifetime EP0505812B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE4109945 1991-03-26
DE4109945A DE4109945A1 (en) 1991-03-26 1991-03-26 METHOD FOR DEEP TEMPERATURE DISPOSAL OF AIR

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EP0505812A1 EP0505812A1 (en) 1992-09-30
EP0505812B1 true EP0505812B1 (en) 1995-10-18

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EP (1) EP0505812B1 (en)
CN (1) CN1064125C (en)
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DK (1) DK0505812T3 (en)
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Cited By (21)

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DE102007031759A1 (en) 2007-07-07 2009-01-08 Linde Ag Method and apparatus for producing gaseous pressure product by cryogenic separation of air
DE102007031765A1 (en) 2007-07-07 2009-01-08 Linde Ag Process for the cryogenic separation of air
DE102009034979A1 (en) 2009-04-28 2010-11-04 Linde Aktiengesellschaft Method for producing pressurized oxygen by evaporating liquid oxygen using a copper and nickel heat exchanger block
EP2312248A1 (en) 2009-10-07 2011-04-20 Linde Aktiengesellschaft Method and device for obtaining pressurised oxygen and krypton/xenon
EP2458311A1 (en) 2010-11-25 2012-05-30 Linde Aktiengesellschaft Method and device for creating a gaseous, pressurised product by the cryogenic decomposition of air
DE102010052544A1 (en) 2010-11-25 2012-05-31 Linde Ag Process for obtaining a gaseous product by cryogenic separation of air
EP2520886A1 (en) 2011-05-05 2012-11-07 Linde AG Method and device for creating gaseous oxygen pressurised product by the cryogenic decomposition of air
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DE102011121314A1 (en) 2011-12-16 2013-06-20 Linde Aktiengesellschaft Method for producing gaseous oxygen product in main heat exchanger system in distillation column system, involves providing turbines, where one of turbines drives compressor, and other turbine drives generator
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Families Citing this family (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5379598A (en) * 1993-08-23 1995-01-10 The Boc Group, Inc. Cryogenic rectification process and apparatus for vaporizing a pumped liquid product
FR2728663B1 (en) 1994-12-23 1997-01-24 Air Liquide PROCESS FOR SEPARATING A GASEOUS MIXTURE BY CRYOGENIC DISTILLATION
US5802873A (en) * 1997-05-08 1998-09-08 Praxair Technology, Inc. Cryogenic rectification system with dual feed air turboexpansion
US5758515A (en) * 1997-05-08 1998-06-02 Praxair Technology, Inc. Cryogenic air separation with warm turbine recycle
US5924307A (en) * 1997-05-19 1999-07-20 Praxair Technology, Inc. Turbine/motor (generator) driven booster compressor
US5934105A (en) * 1998-03-04 1999-08-10 Praxair Technology, Inc. Cryogenic air separation system for dual pressure feed
US5901579A (en) * 1998-04-03 1999-05-11 Praxair Technology, Inc. Cryogenic air separation system with integrated machine compression
US6000239A (en) * 1998-07-10 1999-12-14 Praxair Technology, Inc. Cryogenic air separation system with high ratio turboexpansion
JP4782380B2 (en) * 2003-03-26 2011-09-28 エア・ウォーター株式会社 Air separation device
JP4515225B2 (en) * 2004-11-08 2010-07-28 大陽日酸株式会社 Nitrogen production method and apparatus
US7263859B2 (en) * 2004-12-27 2007-09-04 L'air Liquide, Societe Anonyme A Directoire Et Conseil De Surveillance Pour L'etude Et L'exploitation Des Procedes Georges Claude Process and apparatus for cooling a stream of compressed air
US7437890B2 (en) * 2006-01-12 2008-10-21 Praxair Technology, Inc. Cryogenic air separation system with multi-pressure air liquefaction
CN102721263A (en) * 2012-07-12 2012-10-10 杭州杭氧股份有限公司 System and method for separating air by utilizing cryogenic cooling technology
US20150168056A1 (en) * 2013-12-17 2015-06-18 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Method For Producing Pressurized Gaseous Oxygen Through The Cryogenic Separation Of Air
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Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1520103A (en) * 1977-03-19 1978-08-02 Air Prod & Chem Production of liquid oxygen and/or liquid nitrogen
FR2461906A1 (en) * 1979-07-20 1981-02-06 Air Liquide CRYOGENIC AIR SEPARATION METHOD AND INSTALLATION WITH OXYGEN PRODUCTION AT HIGH PRESSURE
JPS62102074A (en) * 1985-10-30 1987-05-12 株式会社日立製作所 Method of separating gas
US4715873A (en) * 1986-04-24 1987-12-29 Air Products And Chemicals, Inc. Liquefied gases using an air recycle liquefier
DE3643359C2 (en) * 1986-12-18 1993-11-18 Linde Ag Process and device for air separation by two-stage rectification
DE3738559A1 (en) * 1987-11-13 1989-05-24 Linde Ag METHOD FOR AIR DISASSEMBLY BY DEEP TEMPERATURE RECTIFICATION
DE3817244A1 (en) * 1988-05-20 1989-11-23 Linde Ag METHOD FOR DEEP TEMPERATURE DISPOSAL OF AIR
GB8904275D0 (en) * 1989-02-24 1989-04-12 Boc Group Plc Air separation
US5114449A (en) * 1990-08-28 1992-05-19 Air Products And Chemicals, Inc. Enhanced recovery of argon from cryogenic air separation cycles

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Also Published As

Publication number Publication date
AU653120B2 (en) 1994-09-15
DE4109945A1 (en) 1992-10-01
DE59204027D1 (en) 1995-11-23
DK0505812T3 (en) 1995-12-18
EP0505812A1 (en) 1992-09-30
ES2077898T3 (en) 1995-12-01
US5263328A (en) 1993-11-23
AU1316692A (en) 1992-10-01
CA2063928C (en) 2003-05-06
CN1064125C (en) 2001-04-04
ZA922185B (en) 1993-09-24
ATE129336T1 (en) 1995-11-15
CA2063928A1 (en) 1992-09-27
CN1065326A (en) 1992-10-14

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