EP1767884A1 - Verfahren und Vorrichtung zur Tieftemperaturzerlegung von Luft - Google Patents

Verfahren und Vorrichtung zur Tieftemperaturzerlegung von Luft Download PDF

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Publication number
EP1767884A1
EP1767884A1 EP05108826A EP05108826A EP1767884A1 EP 1767884 A1 EP1767884 A1 EP 1767884A1 EP 05108826 A EP05108826 A EP 05108826A EP 05108826 A EP05108826 A EP 05108826A EP 1767884 A1 EP1767884 A1 EP 1767884A1
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EP
European Patent Office
Prior art keywords
air
heat exchanger
column
compressor
outlet pressure
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Application number
EP05108826A
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English (en)
French (fr)
Inventor
Jean-Pierre Tranier
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude
Original Assignee
LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude
LAir Liquide SA a Directoire et Conseil de Surveillance pour lEtude et lExploitation des Procedes Georges Claude
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Application filed by LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude, LAir Liquide SA a Directoire et Conseil de Surveillance pour lEtude et lExploitation des Procedes Georges Claude filed Critical LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude
Priority to EP05108826A priority Critical patent/EP1767884A1/de
Priority to JP2008531702A priority patent/JP2009509120A/ja
Priority to CNA2006800349904A priority patent/CN101268326A/zh
Priority to US12/067,672 priority patent/US20080223075A1/en
Priority to PCT/EP2006/066601 priority patent/WO2007039478A1/en
Priority to EP06793721A priority patent/EP1938032A1/de
Publication of EP1767884A1 publication Critical patent/EP1767884A1/de
Withdrawn legal-status Critical Current

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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25JLIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02Processes 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
    • F25J3/04Processes 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
    • F25J3/04006Providing pressurised feed air or process streams within or from the air fractionation unit
    • F25J3/04109Arrangements of compressors and /or their drivers
    • F25J3/04139Combination of different types of drivers mechanically coupled to the same compressor, possibly split on multiple compressor casings
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25JLIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02Processes 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
    • F25J3/04Processes 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
    • F25J3/04006Providing pressurised feed air or process streams within or from the air fractionation unit
    • F25J3/04012Providing 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
    • F25J3/04024Providing 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
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25JLIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02Processes 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
    • F25J3/04Processes 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
    • F25J3/04006Providing pressurised feed air or process streams within or from the air fractionation unit
    • F25J3/04078Providing 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
    • F25J3/0409Providing 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
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25JLIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
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    • F25J3/04Processes 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
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    • F25J3/04109Arrangements of compressors and /or their drivers
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    • F25J3/02Processes 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
    • F25J3/04Processes 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
    • F25J3/04006Providing pressurised feed air or process streams within or from the air fractionation unit
    • F25J3/04109Arrangements of compressors and /or their drivers
    • F25J3/04145Mechanically coupling of different compressors of the air fractionation process to the same driver(s)
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    • F25J3/04248Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion
    • F25J3/04278Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion using external refrigeration units, e.g. closed mechanical or regenerative refrigeration units
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25JLIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
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    • F25J3/04Processes 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
    • F25J3/04248Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion
    • F25J3/04284Generation 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
    • F25J3/0429Generation 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
    • F25J3/04296Claude expansion, i.e. expanded into the main or high pressure column
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
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    • F25JLIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02Processes 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
    • F25J3/04Processes 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
    • F25J3/04248Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion
    • F25J3/04284Generation 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
    • F25J3/0429Generation 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
    • F25J3/04303Lachmann expansion, i.e. expanded into oxygen producing or low pressure column
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25JLIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02Processes 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
    • F25J3/04Processes 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
    • F25J3/04248Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion
    • F25J3/04284Generation 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
    • F25J3/04309Generation 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 nitrogen
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25JLIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02Processes 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
    • F25J3/04Processes 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
    • F25J3/04248Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion
    • F25J3/04375Details relating to the work expansion, e.g. process parameter etc.
    • F25J3/04381Details relating to the work expansion, e.g. process parameter etc. using work extraction by mechanical coupling of compression and expansion so-called companders
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25JLIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02Processes 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
    • F25J3/04Processes 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
    • F25J3/04248Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion
    • F25J3/04375Details relating to the work expansion, e.g. process parameter etc.
    • F25J3/04393Details relating to the work expansion, e.g. process parameter etc. using multiple or multistage gas work expansion
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25JLIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02Processes 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
    • F25J3/04Processes 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
    • F25J3/04406Processes 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
    • F25J3/04412Processes 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
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25JLIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2230/00Processes or apparatus involving steps for increasing the pressure of gaseous process streams
    • F25J2230/08Cold compressor, i.e. suction of the gas at cryogenic temperature and generally without afterstage-cooler
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    • F25JLIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
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    • F25J2230/20Integrated compressor and process expander; Gear box arrangement; Multiple compressors on a common shaft
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    • F25J2270/00Refrigeration techniques used
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    • F25J2270/00Refrigeration techniques used
    • F25J2270/66Closed external refrigeration cycle with multi component refrigerant [MCR], e.g. mixture of hydrocarbons
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    • F25J2270/90External refrigeration, e.g. conventional closed-loop mechanical refrigeration unit using Freon or NH3, unspecified external refrigeration
    • F25J2270/902Details about the refrigeration cycle used, e.g. composition of refrigerant, arrangement of compressors or cascade, make up sources, use of reflux exchangers etc.
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    • F25J2290/00Other details not covered by groups F25J2200/00 - F25J2280/00
    • F25J2290/12Particular process parameters like pressure, temperature, ratios

Definitions

  • the present invention relates to a process and apparatus for the separation of air by cryogenic distillation. It relates in particular to processes and apparatus for producing oxygen and/or nitrogen at elevated pressure.
  • Gaseous oxygen produced by air separation plants are usually at elevated pressure about 20 to 50 bar.
  • the basic distillation scheme is usually a double column process producing oxygen at the bottom of the low-pressure column operated at 1.4 to 4 bar.
  • the oxygen must be compressed to higher pressure either by oxygen compressor or by the liquid pumping process. Because of the safety issues associated with the oxygen compressors, most recent oxygen plants are based on the liquid pumping process. In order to vaporize liquid oxygen at elevated pressure there is a need for an additional motor-driven booster compressor to raise a portion of the feed air or nitrogen to higher pressure in the range of 40-80 bars. In essence, the booster replaces the oxygen compressor.
  • the air purification unit conceived for a traditional oxygen plant would operate at about 5-7 bar which is essentially the pressure of the high-pressure column, and it is also desirable to raise this pressure to a higher level in order to render the equipment more compact and less costly.
  • a cold compression process as described in US-A-5,475,980 provides a technique to drive the oxygen plant with a single air compressor.
  • air to be distilled is chilled in the main exchanger then further compressed by a booster compressor driven by an expander exhausting into the high-pressure column of a double column process.
  • the discharge pressure of the air compressor is in the range of 15 bar which is also quite advantageous for the purification unit.
  • One inconvenience of this approach is the increase of the size of the main exchanger due to additional flow recycling which is typical for the cold compression plant.
  • An illustration of this prior art is presented in Figure 1, in which an oil brake is added to the system to dissipate the power required for the refrigeration. In larger plants, a compressor and/or a generator can replace the oil brake.
  • An oxygen enriched liquid stream 28 is expanded and sent from the high-pressure column to the low-pressure column.
  • a nitrogen enriched liquid stream 29 is expanded and sent from the high-pressure column to the low-pressure column.
  • High-pressure gaseous nitrogen 14 is removed from the top of the high-pressure column and warmed in the heat exchanger to form a product stream 24.
  • Liquid oxygen 20 is removed from the bottom of the low pressure column 31, pressurized by a pump 21 and sent as stream 22 to the heat exchanger 5 where it vaporizes by heat exchange with the pressurized air 10 to form gaseous pressurized oxygen 23.
  • a top nitrogen enriched gaseous stream 25 is removed from the low-pressure column 31, warmed in the heat exchanger 5 and then forms stream 26.
  • US-A-5901576 describes several arrangements of cold compression schemes utilizing the expansion of vaporized rich liquid of the bottom of the high-pressure column, or the expansion of high-pressure nitrogen to drive the cold compressor. In some cases, motor driven cold compressors were also used. These processes also operate with feed air at about the high-pressure column's pressure and in most cases a booster compressor is also needed.
  • US-A-6,626,008 describes a heat pump cycle utilizing a cold compressor to improve the distillation process for the production of low purity oxygen for a double vaporizer oxygen process. Low air pressure and a booster compressor are also typical for this kind of process.
  • a process for separating air by cryogenic distillation in a column system comprising a high pressure column and a low pressure column comprising the steps of:
  • an apparatus for the separation of air by cryogenic distillation comprising:
  • the apparatus may include a further expander and means for sending nitrogen from a column of the column system or air to the further expander.
  • one of the second and third compressors may be coupled to the expander and the other of the second and third compressors may be coupled to the further expander.
  • At least one of the second and third compressors is coupled to the air expander.
  • conduit for sending a first part of the air at the first outlet pressure to the second compressor is connected to an intermediate point of the heat exchanger.
  • the second and third compressors are connected in series.
  • the expander may be chosen from the group including an air expander whose outlet is connected to the high pressure column, an air expander whose outlet is connected to the low pressure column, a high pressure nitrogen expander and a low pressure nitrogen expander.
  • the apparatus may include a further expander chosen from the group including an air expander whose outlet is connected to the high pressure column, an air expander whose outlet is connected to the low pressure column, a high pressure nitrogen expander and a low pressure nitrogen expander.
  • the further expander is coupled to one of the second and third expanders.
  • atmospheric air is compressed by the air compressor 1 and purified in the purification unit 2 to yield an air stream (stream 11) free of impurities such as moisture and carbon dioxide that can freeze in the cryogenic equipment.
  • a first portion of this air is compressed in a booster brake compressor 3 to raise its pressure further.
  • This pressurized first portion (stream 4) is then cooled in the main exchanger 5 to condense to form a liquefied air stream (stream 27), which is fed to at least one of the distillation columns, following expansion in a valve.
  • the air may liquefy within or downstream the main exchanger depending on the pressure used.
  • An auxiliary fluid mixture 6 of krypton (90%) and oxygen (10%) is introduced in heat exchanger 5 when it is vaporized and slightly warmed after vaporization to yield a cold auxiliary gaseous stream at an intermediate temperature T1. At least a portion of this cold auxiliary stream (stream 7) is sent to a cold brake compressor 8 at temperature T1 to be compressed to raise its pressure (stream 9). Stream 9 is then sent back to the exchanger at temperature T2 which is greater than T1 and cooled in exchanger 5 to condense to form a liquefied auxiliary stream (stream 10), which is expanded in a valve 16 to form stream 6.
  • a phase separator could be added if stream 6 is a two-phase fluid, the liquid phase being introduced in heat exchanger 5 and the vapor phase mixed with stream 7.
  • the second portion of stream 11 (stream 12) is cooled in exchanger 5 to yield stream 15, which is sent to the expander 13 at an inlet temperature of T3, for expansion into the high pressure column. It is preferable that the power generated by expander 13 be used to drive the booster brake compressor 3.
  • the rest of stream 12 is liquefied as stream 33 and sent to the high pressure column 30.
  • Nitrogen rich gas 14 can be extracted from the high pressure column 30, warmed in exchanger 5 to form stream 17, which is then expanded in expander 18 having an inlet temperature T4.
  • the power of expander 18 can be preferably used to drive the cold booster brake compressor 8.
  • the exhaust of expander 18 (stream 19) then returns to the cold end of exchanger 5 to be re-heated to close to ambient temperature forming stream 24.
  • Pump 21 boosts the pressure of liquid oxygen product 20 extracted at the bottom of the low pressure column 31 to the desired pressure then sends pressurized oxygen stream 22 to exchanger 5 for vaporization and heating to yield the oxygen product 23.
  • the double column system is a traditional type of two-column process as described in numerous patents or papers on air separation technology having a high pressure column 30 and a low pressure column 31, thermally linked by a reboiler-condenser at the bottom of the low pressure column.
  • An argon column (not shown) can be used with the double column system to provide a concentrated argon stream.
  • T1, T2, T3 and T4 are provided as the preferred arrangement. Above, going from the hottest temperature to the coldest the temperatures are T2, T5, T1 and T3. Depending upon the pressure of the vaporized oxygen and the pressure of the column system the order of these temperatures can be modified to optimize the performance of the process.
  • booster brake compressors 3 is a single stage compressor and is usually provided as part of the expander-booster package and therefore its construction is much simpler and its cost structure much lower than the stand-alone or motor-driven booster compressor.
  • compressor 3 may be a stand-alone or motor-driven booster compressor.
  • Compressor 8 could be either a stand-alone or motor driven booster compressor with one to four stages depending upon the pressure of stream 4 and stream 23. It could be driven directly by expander 18 (alternately expander 13) at the same speed or through a gear to optimize the performances of the booster and expander.
  • a portion 53 of the air at the exhaust stream 54 of expander 13 can be warmed in the exchanger 5 then send to the expander 52 for expansion into the low pressure column.
  • the nitrogen rich gas 14 can be extracted and produced directly off the high pressure column 30 to yield the nitrogen product 41.
  • the tandem expander and booster brakes can be mechanically integrated into a single train: the power of the expander 13 drives the two compressor brakes 3 (single stage) and 8 (double stage).
  • a motor and/or generator 60 can extract or add mechanical power to the system depending on the performance and production expected from the plant at a certain time.
  • a speed changer (gear) can be used to optimize the system performance.
  • An illustration of the arrangement with gear is presented in Figure 7. A further expander 18, 52 could also be added to such a system.
  • the process may be modified to vaporize pumped liquid nitrogen as an additional stream or as a stream replacing the pumped oxygen stream.
  • some of the low pressure nitrogen may be expanded in an expander 18.

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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)
EP05108826A 2005-09-23 2005-09-23 Verfahren und Vorrichtung zur Tieftemperaturzerlegung von Luft Withdrawn EP1767884A1 (de)

Priority Applications (6)

Application Number Priority Date Filing Date Title
EP05108826A EP1767884A1 (de) 2005-09-23 2005-09-23 Verfahren und Vorrichtung zur Tieftemperaturzerlegung von Luft
JP2008531702A JP2009509120A (ja) 2005-09-23 2006-09-21 低温蒸留による空気の分離方法及び装置。
CNA2006800349904A CN101268326A (zh) 2005-09-23 2006-09-21 用于通过低温蒸馏分离空气的方法和设备
US12/067,672 US20080223075A1 (en) 2005-09-23 2006-09-21 Process and Apparatus for the Separation of Air by Cryogenic Distillation
PCT/EP2006/066601 WO2007039478A1 (en) 2005-09-23 2006-09-21 Process and apparatus for the separation of air by cryogenic distillation
EP06793721A EP1938032A1 (de) 2005-09-23 2006-09-21 Verfahren und vorrichtung zur trennung von luft durch kryogene destillation

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EP06793721A Withdrawn EP1938032A1 (de) 2005-09-23 2006-09-21 Verfahren und vorrichtung zur trennung von luft durch kryogene destillation

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EP3101374A3 (de) * 2015-06-03 2017-01-18 Linde Aktiengesellschaft Verfahren und anlage zur tieftemperaturzerlegung von luft
EP3575717A3 (de) * 2018-05-31 2020-03-11 Air Products And Chemicals, Inc. Verfahren und vorrichtung zur lufttrennung mit einem geteilten hauptwärmetauscher

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EP2369281A1 (de) * 2010-03-09 2011-09-28 Linde Aktiengesellschaft Verfahren und Vorrichtung zur Tieftemperaturzerlegung von Luft
CN102721262A (zh) * 2012-07-04 2012-10-10 开封空分集团有限公司 粗氪氙的提取装置及利用该装置提取粗氪氙的工艺
WO2014128959A1 (ja) * 2013-02-25 2014-08-28 三菱重工コンプレッサ株式会社 二酸化炭素液化装置
JP6290703B2 (ja) * 2014-05-08 2018-03-07 レール・リキード−ソシエテ・アノニム・プール・レテュード・エ・レクスプロワタシオン・デ・プロセデ・ジョルジュ・クロード 液化ガスの製造装置および製造方法
EP2980514A1 (de) * 2014-07-31 2016-02-03 Linde Aktiengesellschaft Verfahren zur Tieftemperaturzerlegung von Luft und Luftzerlegungsanlage
US20160245585A1 (en) * 2015-02-24 2016-08-25 Henry E. Howard System and method for integrated air separation and liquefaction
US20200355429A1 (en) * 2017-11-29 2020-11-12 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Cryogenic distillation method and apparatus for producing pressurized air by means of expander booster in linkage with nitrogen expander for braking
US11578916B2 (en) * 2017-12-29 2023-02-14 L'Air Liquide, Societe Anonyme Pour L'Etude Et L'Exploitation Des Procedes Georqes Claude Method and device for producing air product based on cryogenic rectification
FR3090831B1 (fr) 2018-12-21 2022-06-03 L´Air Liquide Sa Pour L’Etude Et L’Exploitation Des Procedes Georges Claude Appareil et procédé de séparation d’air par distillation cryogénique
EP4004468B1 (de) * 2019-07-26 2024-07-17 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Verfahren und vorrichtung zur trennung von luft durch kryogenische destillation
CN114017992B (zh) * 2021-11-09 2023-03-31 四川空分设备(集团)有限责任公司 一种适用于lng冷能负荷变化的空分***

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US20080223075A1 (en) 2008-09-18
WO2007039478A1 (en) 2007-04-12
EP1938032A1 (de) 2008-07-02
JP2009509120A (ja) 2009-03-05
CN101268326A (zh) 2008-09-17

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