EP0547946A1 - Verfahren und Apparat zur Herstellung unreinen Sauerstoffs - Google Patents

Verfahren und Apparat zur Herstellung unreinen Sauerstoffs Download PDF

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Publication number
EP0547946A1
EP0547946A1 EP92403330A EP92403330A EP0547946A1 EP 0547946 A1 EP0547946 A1 EP 0547946A1 EP 92403330 A EP92403330 A EP 92403330A EP 92403330 A EP92403330 A EP 92403330A EP 0547946 A1 EP0547946 A1 EP 0547946A1
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EP
European Patent Office
Prior art keywords
column
pressure column
nitrogen
pressure
medium 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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EP92403330A
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English (en)
French (fr)
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EP0547946B1 (de
EP0547946B2 (de
Inventor
Jean-Louis Girault
Philippe Mazieres
Jean-Pierre Tranier
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Air Liquide SA
LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude
Original Assignee
Air Liquide SA
LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude
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Application filed by Air Liquide SA, LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude filed Critical Air Liquide SA
Priority to EP96200235A priority Critical patent/EP0713069B1/de
Publication of EP0547946A1 publication Critical patent/EP0547946A1/de
Publication of EP0547946B1 publication Critical patent/EP0547946B1/de
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Publication of EP0547946B2 publication Critical patent/EP0547946B2/de
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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
    • F25J3/04151—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
    • F25J3/04206—Division of the main heat exchange line in consecutive sections having different functions including a so-called "auxiliary vaporiser" for vaporising and producing a gaseous product
    • 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
    • F25J3/04248—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
    • F25J3/04248—Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion
    • F25J3/04333—Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion using quasi-closed loop internal vapor compression refrigeration cycles, e.g. of intermediate or oxygen enriched (waste-)streams
    • F25J3/04351—Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion using quasi-closed loop internal vapor compression refrigeration cycles, e.g. of intermediate or oxygen enriched (waste-)streams of nitrogen
    • 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
    • F25J3/04418—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 with thermally overlapping high and low pressure columns
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2200/00—Processes or apparatus using separation by rectification
    • F25J2200/20—Processes or apparatus using separation by rectification in an elevated pressure multiple column system wherein the lowest pressure column is at a pressure well above the minimum pressure needed to overcome pressure drop to reject the products to atmosphere
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2200/00—Processes or apparatus using separation by rectification
    • F25J2200/50—Processes or apparatus using separation by rectification using multiple (re-)boiler-condensers at different heights of the column
    • F25J2200/52—Processes or apparatus using separation by rectification using multiple (re-)boiler-condensers at different heights of the column in the high pressure column of a double pressure main column system
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2200/00—Processes or apparatus using separation by rectification
    • F25J2200/50—Processes or apparatus using separation by rectification using multiple (re-)boiler-condensers at different heights of the column
    • F25J2200/54—Processes or apparatus using separation by rectification using multiple (re-)boiler-condensers at different heights of the column in the low pressure column of a double pressure main column system
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2200/00—Processes or apparatus using separation by rectification
    • F25J2200/90—Details relating to column internals, e.g. structured packing, gas or liquid distribution
    • 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
    • F25J2210/00—Processes characterised by the type or other details of the feed stream
    • F25J2210/42—Nitrogen
    • 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
    • F25J2250/00—Details related to the use of reboiler-condensers
    • F25J2250/10—Boiler-condenser with superposed stages
    • 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
    • F25J2250/00—Details related to the use of reboiler-condensers
    • F25J2250/20—Boiler-condenser with multiple exchanger cores in parallel or with multiple re-boiling or condensing streams
    • 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
    • F25J2250/00—Details related to the use of reboiler-condensers
    • F25J2250/30—External or auxiliary boiler-condenser in general, e.g. without a specified fluid or one fluid is not a primary air component or an intermediate fluid
    • F25J2250/40—One 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
    • F25J2250/00—Details related to the use of reboiler-condensers
    • F25J2250/30—External or auxiliary boiler-condenser in general, e.g. without a specified fluid or one fluid is not a primary air component or an intermediate fluid
    • F25J2250/50—One fluid being oxygen
    • 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 present invention relates to a process for producing impure oxygen by air distillation in a double column air distillation installation, the double column comprising a medium pressure column and a low pressure column.
  • the applications concerned by the invention are those which consume large quantities of impure oxygen. These include the gasification processes for coal or petroleum residues, as well as the direct reduction-smelting processes of iron ore.
  • One known means of developing this pressure consists of combining the air distillation apparatus with a gas turbine: the air to be separated is taken wholly or partially at the discharge from the compressor of this turbine, and the low pressure waste gas from the distillation apparatus is returned after compression to the gas turbine, the impure oxygen and the nitrogen being sent to use under the pressure of the column which product.
  • the invention aims to further reduce the energy expenditure necessary for the production of impure oxygen.
  • the invention also relates to an air distillation installation with double column intended for the implementation of such a process.
  • this installation comprises means for supplying the medium pressure column with air to be distilled at at least about 9 bar absolute, and the low pressure column comprises at least two superposed vaporizers-condensers, including one vaporizer-condenser means, means for supplying this tank evaporator-condenser with a first vaporization gas less volatile than the head nitrogen of the medium pressure column, means for supplying the second evaporator-condenser with nitrogen head the medium pressure column, and means for sending the nitrogen thus condensed under reflux at the head of the medium pressure column.
  • FIGS. 1 to 4 schematically represent four embodiments of the air distillation installation in accordance with the invention.
  • the installation shown in Figure 1 is intended to produce oxygen at a purity of the order of 85% under a pressure of the order of 7.4 bar absolute. It essentially comprises a double column 1 for air distillation, consisting of a medium pressure column (or “MP column”) 2 operating at 15.7 bar absolute and a low pressure column (or “LP column”) 3 operating at 6.3 bar absolute, a main heat exchange line 4, a sub-cooler 5, an auxiliary evaporator-condenser 6 and a turbine 7 for blowing air into the low pressure column.
  • Column 3 is superimposed on column 2 and contains in the tank a vaporizer-condenser and, above this, a second vaporizer-condenser 9.
  • the air to be distilled arrives at medium pressure via a line 10 and enters the exchange line 4. Most of this air is cooled to the vicinity of its dew point and leaves the cold end of the line d 'exchange, the rest having left the exchange line at an intermediate temperature, expanded at low pressure in the turbine 7 to keep the installation cold, and blown at an intermediate level in the LP column 3.
  • a fraction of the fully cooled air is introduced, via a pipe 11, at the base of the column MP 2, and the rest is condensed in the vaporizer-condenser 6; part of the liquid obtained is introduced via a line 12 at an intermediate point in column 2, and the rest is, after sub-cooling in 5 and expansion in an expansion valve 13, introduced at an intermediate point in column BP 3 .
  • the "rich liquid” (air enriched in oxygen) collected in the bottom of the MP column is, after sub-cooling in 5 and expansion in an expansion valve 14, introduced at an intermediate point of the LP column.
  • “lean liquid” (impure nitrogen) drawn off at an intermediate point of the column MP is, after sub-cooling in 5 and expansion in an expansion valve 15, introduced at the top of the column BP.
  • the approximately pure nitrogen produced at the head of the MP column is partly removed from the installation as a product, after heating in the exchange line, via a line 16, and, for the rest, sent in the form gas via a line 17, under medium pressure, in the upper evaporator-condenser 9. After condensation, this nitrogen is returned to reflux at the top of the column MP via a line 18.
  • impure nitrogen gas drawn off at an intermediate point in column 2 and, in this example, at the same level as the lean liquid, is sent via a line 19, at medium pressure, to the evaporator-condenser lower 8.
  • the liquid thus obtained is returned under reflux to the column MP, at approximately the same level, via a pipe 20.
  • the pump 23 could be omitted, the impure oxygen then being vaporized at 6 under the low pressure.
  • the temperature of the bottom liquid of the LP column is determined by that of the gas condensed in this vaporizer-condenser.
  • the temperature of the tank liquid, which is impure oxygen is relatively high. Consequently, for a desired purity of this impure oxygen, the pressure of the BP column, that is to say the low pressure, can be increased.
  • impure oxygen and impure nitrogen are obtained under increased pressure, which makes it possible to make savings on their recovery, for example on the energy required to compress the impure nitrogen to the desired pressure in a gas turbine (not shown) coupled to the installation, for example as described in the aforementioned US-A-4,224,045.
  • the upper vaporizer-condenser 9 serves to provide the necessary reflux at the head of the column MP.
  • the impure oxygen is withdrawn in gaseous form from the LP column 3, and is simply reheated in the exchange line 4 before its evacuation via the pipe 24. This is particularly advantageous when the impure oxygen is desired under the low pressure. Consequently, the vaporizer-condenser 6 is eliminated.
  • a fraction of the medium pressure air cooled near its dew point is sent, via a line 26, to the lower vaporizer-condenser 8 in place of the intermediate gas of Figure 1.
  • This intermediate gas feeds an intermediate vaporizer-condenser 27 located between the lower vaporizers-condensers 8 and upper 9.
  • the liquefied air from the vaporizer-condenser 8 is sent partly, via a line 28, to the column MP and partly, after sub-cooling in 5 and expansion in the expansion valve 13, in the column BP.
  • the impure oxygen is withdrawn in liquid form from the tank of the LP column, then is brought by a pump 23 to the desired production pressure, then vaporized and heated under this pressure in the exchange line 4 before being evacuated from the installation via line 24.
  • a nitrogen cycle is provided, known as the rectification support cycle, which is used at the same time to ensure the vaporization of impure oxygen: part of the nitrogen produced at the head of column 3 (which, in this case, has at the head a "minaret" 30 which is fed at its top by pure liquid nitrogen coming from the upper evaporator-condenser 9 and which, consequently, produces pure nitrogen under the low pressure) is, after heating in the exchange line, compressed by a compressor 31 at medium pressure.
  • This medium pressure nitrogen combined with a medium pressure nitrogen stream taken from the pipe 16, is compressed again by a compressor 33 to a vaporization pressure of the impure oxygen compressed by the pump 23, liquefied in the line of exchange, then, after expansion in an expansion valve 34, introduced under reflux at the head of the column MP.
  • FIG. 4 also includes a BP 3 column with a minaret 30.
  • a BP 3 column with a minaret 30 is high pressure air, boosted to a vaporization pressure of the impure oxygen by a booster 35, which ensures the vaporization of the impure oxygen in the exchange line 4.
  • this air is, after liquefaction and expansion in an expansion valve 36 and in the expansion valve 13, distributed between the two columns 2 and 3. consequently, the compressor 33 and the expansion valve 34 of FIG. 3 are eliminated.
  • the nitrogen coming from the compressor 31, compressed to a pressure higher than the medium pressure feeds in gaseous form, after cooling in the exchange line, the lower evaporator-condenser 8, and the resulting liquid nitrogen is, after expansion in an expansion valve 37, combined with medium pressure liquid nitrogen from the upper evaporator-condenser 9.
  • This nitrogen pressure can be chosen between medium pressure and the pressure for which the nitrogen condenses at the cold end of the exchange line .

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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)
EP92403330A 1991-12-18 1992-12-09 Verfahren zur Herstellung unreinen Sauerstoffs Expired - Lifetime EP0547946B2 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP96200235A EP0713069B1 (de) 1991-12-18 1992-12-09 Verfahren und Anlage zur Lufttrennung

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR9115705A FR2685459B1 (fr) 1991-12-18 1991-12-18 Procede et installation de production d'oxygene impur.
FR9115705 1991-12-18

Related Child Applications (2)

Application Number Title Priority Date Filing Date
EP96200235A Division EP0713069B1 (de) 1991-12-18 1992-12-09 Verfahren und Anlage zur Lufttrennung
EP96200235.8 Division-Into 1992-12-09

Publications (3)

Publication Number Publication Date
EP0547946A1 true EP0547946A1 (de) 1993-06-23
EP0547946B1 EP0547946B1 (de) 1996-10-09
EP0547946B2 EP0547946B2 (de) 2000-03-22

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ID=9420168

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EP92403330A Expired - Lifetime EP0547946B2 (de) 1991-12-18 1992-12-09 Verfahren zur Herstellung unreinen Sauerstoffs
EP96200235A Expired - Lifetime EP0713069B1 (de) 1991-12-18 1992-12-09 Verfahren und Anlage zur Lufttrennung

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EP96200235A Expired - Lifetime EP0713069B1 (de) 1991-12-18 1992-12-09 Verfahren und Anlage zur Lufttrennung

Country Status (9)

Country Link
US (1) US5392609A (de)
EP (2) EP0547946B2 (de)
CN (1) CN1068428C (de)
AU (1) AU654601B2 (de)
BR (1) BR9205050A (de)
CA (1) CA2085561A1 (de)
DE (2) DE69214409T3 (de)
ES (2) ES2092661T3 (de)
FR (1) FR2685459B1 (de)

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EP0646755A1 (de) * 1993-09-15 1995-04-05 Air Products And Chemicals, Inc. Verfahren zur Tieftemperaturzerlegung von Luft für die Herstellung von Stickstoff unter erhöhtem Druck mittels gepumpten flüssigen Stickstoffs
EP0766053A2 (de) * 1995-09-29 1997-04-02 Praxair Technology, Inc. Kryogenisches Rektifikationssystem zur Herstellung von Sauerstoff mit doppelter Reinheit
EP1284404A1 (de) * 2001-08-13 2003-02-19 Linde Aktiengesellschaft Verfahren und Vorrichtung zur Gewinnung eines Druckprodukts durch Tieftemperaturzerlegung von Luft
WO2012136939A2 (fr) 2011-04-08 2012-10-11 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Procede et appareil de separation d'air par distillation cryogenique

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US5611219A (en) * 1996-03-19 1997-03-18 Praxair Technology, Inc. Air boiling cryogenic rectification system with staged feed air condensation
US5678427A (en) * 1996-06-27 1997-10-21 Praxair Technology, Inc. Cryogenic rectification system for producing low purity oxygen and high purity nitrogen
US5669236A (en) * 1996-08-05 1997-09-23 Praxair Technology, Inc. Cryogenic rectification system for producing low purity oxygen and high purity oxygen
US5664438A (en) * 1996-08-13 1997-09-09 Praxair Technology, Inc. Cryogenic side column rectification system for producing low purity oxygen and high purity nitrogen
US5682762A (en) * 1996-10-01 1997-11-04 Air Products And Chemicals, Inc. Process to produce high pressure nitrogen using a high pressure column and one or more lower pressure columns
US5675977A (en) * 1996-11-07 1997-10-14 Praxair Technology, Inc. Cryogenic rectification system with kettle liquid column
US5761927A (en) * 1997-04-29 1998-06-09 Air Products And Chemicals, Inc. Process to produce nitrogen using a double column and three reboiler/condensers
US5836175A (en) * 1997-08-29 1998-11-17 Praxair Technology, Inc. Dual column cryogenic rectification system for producing nitrogen
US5839296A (en) * 1997-09-09 1998-11-24 Praxair Technology, Inc. High pressure, improved efficiency cryogenic rectification system for low purity oxygen production
ATE228203T1 (de) 1997-09-26 2002-12-15 Siemens Ag Gehäuse für eine strömungsmaschine
US5806342A (en) * 1997-10-15 1998-09-15 Praxair Technology, Inc. Cryogenic rectification system for producing low purity oxygen and high purity oxygen
US5956972A (en) * 1997-12-23 1999-09-28 The Boc Group, Inc. Method of operating a lower pressure column of a double column distillation unit
US6253576B1 (en) * 1999-11-09 2001-07-03 Air Products And Chemicals, Inc. Process for the production of intermediate pressure oxygen
DE10205878A1 (de) * 2002-02-13 2003-08-21 Linde Ag Tieftemperatur-Luftzerlegungsverfahren
FR2930330B1 (fr) * 2008-04-22 2013-09-13 Air Liquide Procede et appareil de separation d'air par distillation cryogenique
US9453674B2 (en) * 2013-12-16 2016-09-27 Praxair Technology, Inc. Main heat exchange system and method for reboiling
CN106989567A (zh) * 2017-04-25 2017-07-28 河南开元空分集团有限公司 一种低能耗的同时生产富氧气体和高纯氮气的装置和方法
JP2020521098A (ja) 2017-05-16 2020-07-16 イーバート，テレンス，ジェイ． 気体を液化するための装置およびプロセス

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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0584419A1 (de) * 1992-08-28 1994-03-02 Air Products And Chemicals, Inc. Verfahren und Vorrichtung für die Luftzerlegung durch Rektifikation
EP0646755A1 (de) * 1993-09-15 1995-04-05 Air Products And Chemicals, Inc. Verfahren zur Tieftemperaturzerlegung von Luft für die Herstellung von Stickstoff unter erhöhtem Druck mittels gepumpten flüssigen Stickstoffs
EP0766053A2 (de) * 1995-09-29 1997-04-02 Praxair Technology, Inc. Kryogenisches Rektifikationssystem zur Herstellung von Sauerstoff mit doppelter Reinheit
EP0766053A3 (de) * 1995-09-29 1998-01-14 Praxair Technology, Inc. Kryogenisches Rektifikationssystem zur Herstellung von Sauerstoff mit doppelter Reinheit
EP1284404A1 (de) * 2001-08-13 2003-02-19 Linde Aktiengesellschaft Verfahren und Vorrichtung zur Gewinnung eines Druckprodukts durch Tieftemperaturzerlegung von Luft
US6662595B2 (en) 2001-08-13 2003-12-16 Linde Aktiengesellschaft Process and device for obtaining a compressed product by low temperature separation of air
WO2012136939A2 (fr) 2011-04-08 2012-10-11 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Procede et appareil de separation d'air par distillation cryogenique
US9696087B2 (en) 2011-04-08 2017-07-04 L'Air Liquide Société Anonyme Pour L'Étude Et L'Exploitation Des Procedes Georges Claude Method and apparatus for separating air by cryogenic distillation

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Publication number Publication date
DE69230975T2 (de) 2000-10-05
FR2685459A1 (fr) 1993-06-25
EP0713069A1 (de) 1996-05-22
US5392609A (en) 1995-02-28
BR9205050A (pt) 1993-08-10
ES2092661T3 (es) 1996-12-01
DE69214409T2 (de) 1997-05-22
DE69214409T3 (de) 2000-07-13
CN1068428C (zh) 2001-07-11
CA2085561A1 (fr) 1993-06-19
DE69214409D1 (de) 1996-11-14
ES2145967T3 (es) 2000-07-16
AU654601B2 (en) 1994-11-10
EP0547946B1 (de) 1996-10-09
EP0547946B2 (de) 2000-03-22
AU3022192A (en) 1993-06-24
FR2685459B1 (fr) 1994-02-11
EP0713069B1 (de) 2000-04-26
CN1088301A (zh) 1994-06-22
DE69230975D1 (de) 2000-05-31

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