EP2597409A1 - Process and apparatus for the separation of air by cryogenic distillation - Google Patents

Process and apparatus for the separation of air by cryogenic distillation Download PDF

Info

Publication number
EP2597409A1
EP2597409A1 EP11306552.8A EP11306552A EP2597409A1 EP 2597409 A1 EP2597409 A1 EP 2597409A1 EP 11306552 A EP11306552 A EP 11306552A EP 2597409 A1 EP2597409 A1 EP 2597409A1
Authority
EP
European Patent Office
Prior art keywords
pressure column
column
liquid
conduit
argon
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.)
Granted
Application number
EP11306552.8A
Other languages
German (de)
French (fr)
Other versions
EP2597409B1 (en
Inventor
Bao Ha
Jean-Renaud Brugerolle
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.)
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
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Air Liquide SA, LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude filed Critical Air Liquide SA
Priority to EP11306552.8A priority Critical patent/EP2597409B1/en
Priority to CN201280057446.7A priority patent/CN103988036B/en
Priority to PCT/EP2012/068948 priority patent/WO2013075867A1/en
Priority to US14/359,176 priority patent/US20140318179A1/en
Publication of EP2597409A1 publication Critical patent/EP2597409A1/en
Application granted granted Critical
Publication of EP2597409B1 publication Critical patent/EP2597409B1/en
Not-in-force legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • 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
    • 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
    • F25J3/04048—Providing pressurised feed air or process streams within or from the air fractionation unit by compression of cold gaseous streams, e.g. intermediate or oxygen enriched (waste) streams
    • F25J3/04054—Providing pressurised feed air or process streams within or from the air fractionation unit by compression of cold gaseous streams, e.g. intermediate or oxygen enriched (waste) streams of 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
    • F25J3/04084—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 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
    • F25J3/04006—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
    • F25J3/04151—Purification and (pre-)cooling of the feed air; recuperative heat-exchange with product streams
    • F25J3/04163—Hot end purification of the feed air
    • F25J3/04169—Hot end purification of the feed air by adsorption of the impurities
    • F25J3/04175—Hot end purification of the feed air by adsorption of the impurities at a pressure of substantially more than the highest 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
    • F25J3/04284—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
    • F25J3/04296—Claude expansion, i.e. expanded into the main or high pressure column
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
    • F25J3/04—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air
    • F25J3/04248—Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion
    • F25J3/04375—Details relating to the work expansion, e.g. process parameter etc.
    • F25J3/04393—Details relating to the work expansion, e.g. process parameter etc. using multiple or multistage gas work expansion
    • 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
    • F25J3/04436—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 at least a triple pressure main column system
    • F25J3/04448—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 at least a triple pressure main column system in a double column flowsheet with an intermediate pressure column
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
    • F25J3/04—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream for air
    • F25J3/04642—Recovering noble gases from air
    • F25J3/04648—Recovering noble gases from air argon
    • F25J3/04654—Producing crude argon in a crude argon column
    • F25J3/04709—Producing crude argon in a crude argon column as an auxiliary column system in at least a dual pressure main column system

Definitions

  • the present invention relates to a process and apparatus for the separation of air by cryogenic distillation.
  • an intermediate pressure column can be added to the double column process to improve the distillation performance.
  • the main function of the intermediate pressure column is to distil the rich liquid bottom of the high pressure column to yield additional nitrogen rich liquid reflux for the low pressure column.
  • the intermediate pressure column is usually bottom heated or reboiled by condensing the nitrogen rich gas from the top of the high pressure column.
  • Double column process could have a side-arm column for argon extraction.
  • the reboil of the intermediate pressure column can be provided by feed gas to the argon side-arm column or by some gases derived from the argon column itself.
  • the intermediate pressure column operates at a pressure in between the pressures of the low pressure column and the high pressure column.
  • the argon and intermediate pressure columns can be used with the double column process, for example, to produce argon and to maximize the high pressure nitrogen extraction from the high pressure column. Good process efficiency can be achieved.
  • oxygen enriched liquid at the bottom of the high pressure column is fed to the intermediate pressure column and the resulting liquid extracted from the bottom of the intermediate pressure column is then partially vaporized in the top condensers of the intermediate and argon columns to provide the needed refluxes.
  • EP-A-0828123 utilizes the intermediate pressure column to improve the argon recovery when both liquid oxygen and liquid nitrogen are pumped and vaporized.
  • some liquid air is fed to the intermediate pressure column to produce additional bottom liquid of the intermediate pressure column.
  • Intermediate liquid with composition similar to air is mixed with intermediate pressure column's bottom liquid to provide cooling of the top condenser of the intermediate pressure column.
  • the top condenser of the argon column is also cooled by vaporizing bottom liquid of the intermediate pressure column.
  • Figure 2 discloses the use of the intermediate pressure column to enhance argon recovery.
  • the process is similar to that of EP-A-0828123 but more or almost all liquid air extracted from the high pressure column is sent to the intermediate pressure column to yield additional liquid nitrogen reflux.
  • the bottom stream of the intermediate pressure column is partially vaporized in its top condenser for cooling.
  • the liquid fraction is fed to the top condenser of the argon column and vaporized to supply the needed cooling.
  • the two top condensers of the intermediate and argon columns are in series in terms of receiving vaporizing liquid from the bottom of the intermediate pressure column.
  • a process for the separation of air by cryogenic distillation in a column system including a high pressure column, a low pressure column, the bottom of the low pressure column being thermally coupled with the top of the high pressure column, an intermediate pressure column, operating a pressure between that of the high pressure column and that of the low pressure column, and an argon column wherein:
  • an apparatus for the separation of air by cryogenic distillation comprising a column system including a high pressure column, a low pressure column, the bottom of the low pressure column being thermally coupled with the top of the high pressure column, an intermediate pressure column, operating a pressure between that of the high pressure column and that of the low pressure column, and an argon column a heat exchanger, means for sending purified compressed air to be cooled in the heat exchanger, means for sending cooled purified compressed air from the heat exchanger at least in part to the high pressure column, a conduit for sending nitrogen enriched liquid from the top of the high pressure column to the top of the low pressure column, a conduit for removing oxygen rich liquid from the low pressure column, said conduit being connected to first pressurization means, a conduit for sending pressurized oxygen rich liquid from the first pressurization means to the heat exchanger or another heat exchanger, a conduit for removing nitrogen rich liquid from the column system connected to second pressurization means, a conduit connecting the second pressurization means to the heat exchange
  • Purified air has been treated to remove the water and carbon dioxide which it contains.
  • Oxygen rich liquid contains at least 70% mol. oxygen, preferably at least 85% mol. oxygen. It contains less than 100% mol. oxygen.
  • Nitrogen rich liquid contains at least 85% mol. nitrogen, preferably at least 90% mol nitrogen. It contains less than 100% moll nitrogen.
  • Oxygen enriched liquid contains at least 25% mol oxygen, or at least 30% mol oxygen.
  • the high pressure column operates at between 4 and 8 bar, the intermediate pressure column at between 2 and 3 bar, the argon column at between 1 and 2 bar, the low pressure column at between 1 and 2 bar.
  • the gaseous oxygen produced by pumping and vaporizing can be as low as 2 bar and as high as 80 bar or even 100 bars.
  • the upper limit of the high pressure of pumped oxygen is usually dictated by the maximum allowable working pressure of the brazed heat exchanger.
  • the intermediate stream withdrawn from the high pressure column and sent to the intermediate pressure column top condenser contains between 18 and 25 mol% oxygen.
  • Figure 1 shows the column portion of a process operating according to the invention and Figures 2 and 3 show two alternative corresponding heat exchanger portions, to be used for oxygen pressures above 15 bars abs.
  • gaseous air 2 and liquid air 4 are fed to high pressure column 100.
  • Oxygen enriched liquid 10 formed at the bottom of the high pressure column 100 is divided in two. One portion 12 is expanded and sent to an intermediate level of the low pressure column 101. Another portion 11 is expanded and sent to top condenser 105 of the argon column where it vaporizes to form stream 13 which is sent to the low pressure column 101.
  • all the oxygen enriched liquid 10 can be sent to the condenser 105 and partially condensed. In this case, stream 12 is absent and liquid from condenser 105 is sent to the low pressure column 101.
  • the top of the high pressure column 100 is thermally coupled to the bottom of the low pressure column 101 via a condenser-reboiler 104.
  • Nitrogen enriched liquid 40 from the top of the high pressure column 100 is divided in two, one portion 41 being sent to the top of the low pressure column 101 as reflux. Nitrogen enriched gas is removed from the top of the low pressure column 101.
  • a side liquid stream 20 with composition similar to air, containing between 18 and 25% mol. oxygen is extracted from column 100.
  • the side liquid stream could be replaced or supplemented by a part of liquid air stream 4 or another liquid air stream.
  • a portion 22 of stream 20 (or stream 4, not illustrated) is partially vaporized in the top condenser 107 of intermediate pressure column 103.
  • Condenser 107 could be a falling film vaporizer.
  • the vapor 123 containing around 10% mol. oxygen) is sent to the low pressure column 101.
  • a portion 24 of the liquid fraction 26 of the partially vaporization is then fed to column 103.
  • Column 103 operates at about 2 bar and its condenser 107 at 1.4 bar.
  • Gravity feed or a pump 110 can be used to transfer this liquid from condenser 107 to a position between 2 and 5 theoretical trays above the bottom of intermediate pressure column 103.
  • Oxygen enriched liquid 60 from the bottom of column 103 containing preferably between 70 and 75 mol% oxygen is expanded and sent to the low pressure column. It is useful to note that a liquid air stream formed from the condensation of air for vaporizing liquid oxygen and liquid nitrogen products in the main heat exchanger can be sent to the top condenser of the intermediate column instead of using a part of the liquid stream 20 extracted from the high pressure column.
  • the average temperature difference for condensers 106, 107 should be between 0.8 and 0.9°C.
  • Column 103 produces additional reflux liquid 23 for the top of the low pressure column 101.
  • Column 102 is a typical side-arm argon column for a double column process. A portion 54 of argon enriched feed gas from the low pressure column 101 is separated in the argon column 102 to form argon product 80 in liquid form as shown or in gaseous form. The bottom liquid 52 from the argon column is sent back to the low pressure column 101.
  • a portion 51 of argon enriched feed gas 50 from the low pressure column 101 is condensed in the bottom reboiler 106, preferably of the falling film type, of column 103 to yield liquid 53 which is then fed to column 102 or 101 to be separated.
  • the argon column 102 is equipped with a top condenser 105 which vaporizes a portion 11 of oxygen enriched liquid 10 produced at the bottom of the high pressure column 100.
  • Another portion 45 of stream 40 is pumped by pump 121 to high pressure, vaporized and warmed to yield high pressure nitrogen product.
  • Liquid oxygen 30 produced at the bottom of column 101 is pumped by pump 120 to high pressure, vaporized and warmed to yield high pressure oxygen product.
  • the embodiment shown in Figure 2 can be used to vaporize efficiently the liquid products 31, 42.
  • the liquid products are vaporized in pumps 120,121, the oxygen being pressurized to a pressure between 15 and 80 bars abs.
  • the cold compression technique is utilized and is described as follows:
  • a multi stage booster compressor comprising several stages 209, 210 and 211 is added to further compress the fraction 82 feeding compressor 207.
  • Multiple pressurized streams 95 and 96 can be generated by the booster compressor to vaporize efficiently the liquid products to form liquid air streams 97 and 99.
  • a cold booster has an inlet temperature of below -20°C.

Landscapes

  • 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)

Abstract

An apparatus for the separation of air by cryogenic distillation comprises a column system including a double column (100, 101), an intermediate pressure column (103), operating a pressure between that of the high pressure column and that of the low pressure column, and an argon column (102), a heat exchanger (200), a conduit for sending purified compressed air to be cooled in the heat exchanger, a conduit for sending cooled purified compressed air from the heat exchanger at least in part to the high pressure column, means for pressurizing and vaporizing oxygen rich liquid (30) from the low pressure column, means for pressurizing and vaporizing nitrogen rich liquid (40), a conduit for sending argon enriched gas (50, 54) from the low pressure column to the argon column, said argon column having a top condenser (105), a conduit for removing argon rich fluid (80) from the top of the argon column, a conduit for sending a liquid air stream (4, 20, 22) at least in part to a top condenser (107) of the intermediate pressure column where it is partially vaporized to form a vapor and a liquid, a conduit for sending the vapor (123) formed in the top condenser of the intermediate pressure column to the low pressure column and a conduit for sending the liquid (24) from the top condenser of the intermediate pressure column to the intermediate pressure column to be separated.

Description

  • The present invention relates to a process and apparatus for the separation of air by cryogenic distillation.
  • Most oxygen plants are based on the LOX pumped cycle wherein liquid oxygen is pressurized by pump and vaporized by condensing pressurized air and then warmed to form the pressurized gaseous oxygen product. Usually about 25 to 35% of the feed air is liquefied by vaporizing the oxygen product. The liquid pumped cycle is not only applied for liquid oxygen but some liquid nitrogen can also be vaporized as well based on the same concept. When both liquid oxygen and liquid oxygen are pumped and vaporized by condensing air to form pressurized oxygen and nitrogen, an important quantity of air as high as 50% of total feed air must be liquefied.
  • By producing gaseous oxygen and nitrogen products by pumping liquid, costly product compressors can be avoided resulting in significant cost reduction. However, by liquefying important quantity of feed air, the high pressure column of the double column process is deprived of gaseous feed air such that its ability to provide the liquid reflux for the low pressure column is adversely affected. Reduction of feed air also reduces the condensing gas at the top of the high pressure column and this translates into less reboiler duty for the low pressure column. The distillation performance will suffer when both liquid oxygen and liquid nitrogen in significant quantities are pumped by condensing air. A loss of oxygen recovery will therefore occur. When all liquid oxygen and about the same molar flow of liquid nitrogen are vaporized, as much as 7-10% loss oxygen recovery can be expected. More power and more feed air, i.e. larger plant size, are needed to produce the same quantity of oxygen.
  • In cryogenic air separation technology, an intermediate pressure column can be added to the double column process to improve the distillation performance. The main function of the intermediate pressure column is to distil the rich liquid bottom of the high pressure column to yield additional nitrogen rich liquid reflux for the low pressure column. The intermediate pressure column is usually bottom heated or reboiled by condensing the nitrogen rich gas from the top of the high pressure column. Double column process could have a side-arm column for argon extraction. Sometimes, the reboil of the intermediate pressure column can be provided by feed gas to the argon side-arm column or by some gases derived from the argon column itself. The intermediate pressure column operates at a pressure in between the pressures of the low pressure column and the high pressure column.
  • The argon and intermediate pressure columns can be used with the double column process, for example, to produce argon and to maximize the high pressure nitrogen extraction from the high pressure column. Good process efficiency can be achieved. In those processes, oxygen enriched liquid at the bottom of the high pressure column is fed to the intermediate pressure column and the resulting liquid extracted from the bottom of the intermediate pressure column is then partially vaporized in the top condensers of the intermediate and argon columns to provide the needed refluxes.
  • However, in situations where both liquid oxygen and liquid nitrogen are vaporized, and sometimes with a liquid production requirement, too much liquid air is formed such that the quantity of rich liquid at the bottom of the high pressure column is sharply reduced. Because of this effect, the use of intermediate pressure column with argon column becomes less effective or not practical for the simple reason that there is not sufficient liquid rich to drive the argon and intermediate pressure columns. In some cases, in order to assure a positive temperature difference in the condenser of the intermediate pressure column, some liquid air or liquid rich in nitrogen must be injected or mixed with the bottom liquid to lower its boiling temperature. This mixing can introduce irreversibility in the distillation system and cause a loss of efficiency. The new process addresses the above shortcomings by providing an alternative technique to process the additional liquid air efficiently.
  • The process of EP-A-0828123 utilizes the intermediate pressure column to improve the argon recovery when both liquid oxygen and liquid nitrogen are pumped and vaporized. In order to remedy the issue of lack of oxygen enriched liquid, some liquid air is fed to the intermediate pressure column to produce additional bottom liquid of the intermediate pressure column. Intermediate liquid with composition similar to air is mixed with intermediate pressure column's bottom liquid to provide cooling of the top condenser of the intermediate pressure column. The top condenser of the argon column is also cooled by vaporizing bottom liquid of the intermediate pressure column.
  • In Technical Disclosure IPCOM000019394D, Figure 2 discloses the use of the intermediate pressure column to enhance argon recovery. The process is similar to that of EP-A-0828123 but more or almost all liquid air extracted from the high pressure column is sent to the intermediate pressure column to yield additional liquid nitrogen reflux. The bottom stream of the intermediate pressure column is partially vaporized in its top condenser for cooling. The liquid fraction is fed to the top condenser of the argon column and vaporized to supply the needed cooling. In this arrangement, the two top condensers of the intermediate and argon columns are in series in terms of receiving vaporizing liquid from the bottom of the intermediate pressure column.
  • According to an object of the invention, there is provided a process for the separation of air by cryogenic distillation in a column system including a high pressure column, a low pressure column, the bottom of the low pressure column being thermally coupled with the top of the high pressure column, an intermediate pressure column, operating a pressure between that of the high pressure column and that of the low pressure column, and an argon column wherein:
    1. i) purified compressed air is cooled in a heat exchanger and sent at least in part to the high pressure column,
    2. ii) nitrogen enriched liquid is sent from the top of the high pressure column to the top of the low pressure column,
    3. iii) oxygen rich liquid is removed from the low pressure column, pressurized and vaporized in the heat exchanger or another heat exchanger,
    4. iv) nitrogen rich liquid is removed from the column system, pressurized and vaporized in the heat exchanger or another heat exchanger,
    5. v) argon enriched gas is sent from the low pressure column to the argon column, said argon column having a top condenser, and argon rich fluid is removed from the top of the argon column,
    6. vi) oxygen enriched liquid from the bottom of the high pressure column is partially vaporized in the top condenser of the argon column and the gas thereby formed is sent to the low pressure column,
    7. vii) an intermediate stream is removed at an intermediate point of the high pressure column and sent at least in part to a top condenser of the intermediate pressure column where it is partially vaporized to form a vapor and a liquid,
    8. viii) the vapor formed in the top condenser of the intermediate pressure column is sent to the low pressure column,
    9. ix) the liquid from the top condenser of the intermediate pressure column is sent to the intermediate pressure column to be separated,
    10. x) a liquid from the bottom of the intermediate pressure column is sent to the low pressure column, and
    11. xi) a liquid from the top of the intermediate pressure column is sent to the top of the low pressure column.
  • Preferably:
    • the intermediate pressure column has a bottom reboiler and wherein argon enriched gas from the low pressure column is condensed in the bottom reboiler.
    • the liquid sent from the top condenser of the intermediate pressure column is the only feed to the intermediate pressure column.
    • all the oxygen enriched liquid from the high pressure column is sent to argon column top condenser or to the low pressure column and the argon column top condenser, without passing through the intermediate pressure column top condenser.
    • all the bottom liquid of the intermediate pressure column is sent to the low pressure column without passing through the intermediate pressure column top condenser.
    • part of the liquid from the intermediate pressure column top condenser is sent to the low pressure column.
    • the liquid from the top condenser is sent to the intermediate pressure column between 2 and 5 theoretical trays above the bottom of the intermediate pressure column.
    • at least part of the air is cooled to an intermediate temperature of the heat exchanger, compressed in a compressor, further cooled in the heat exchanger and sent to at least the high pressure column.
    • the bottom liquid of the intermediate pressure column contains at least 70% mol. oxygen.
    • at least one of the bottom reboiler and the top condenser of the intermediate pressure column is a falling film reboiler.
    • at least one part of the feed air is compressed from a first pressure to a second pressure in a warm booster, fed to the heat exchanger at the second pressure, cooled, expanded in a first turboexpander and sent to the high pressure column and at least another part of the feed air is sent to the heat exchanger at the first pressure, divided into three portions, the first portion being compressed from the first pressure to a third pressure in a cold booster, cooled, expanded and sent to the high pressure column, the second portion being expanded in a second turboexpander and sent to the high pressure column and the third portion being cooled to the cold end of the heat exchanger and sent to the high pressure column.
  • According to another object of the invention, there is provided an apparatus for the separation of air by cryogenic distillation comprising a column system including a high pressure column, a low pressure column, the bottom of the low pressure column being thermally coupled with the top of the high pressure column, an intermediate pressure column, operating a pressure between that of the high pressure column and that of the low pressure column, and an argon column a heat exchanger, means for sending purified compressed air to be cooled in the heat exchanger, means for sending cooled purified compressed air from the heat exchanger at least in part to the high pressure column, a conduit for sending nitrogen enriched liquid from the top of the high pressure column to the top of the low pressure column, a conduit for removing oxygen rich liquid from the low pressure column, said conduit being connected to first pressurization means, a conduit for sending pressurized oxygen rich liquid from the first pressurization means to the heat exchanger or another heat exchanger, a conduit for removing nitrogen rich liquid from the column system connected to second pressurization means, a conduit connecting the second pressurization means to the heat exchanger or another heat exchanger, a conduit for sending argon enriched gas from the low pressure column to the argon column, said argon column having a top condenser, a conduit for removing argon rich fluid from the top of the argon column, a conduit for sending oxygen enriched liquid from the bottom of the high pressure column to the top condenser of the argon column to be partially vaporized, a conduit for sending the gas thereby formed to the low pressure column, a conduit for sending an intermediate stream removed at an intermediate point of the high pressure column at least in part to a top condenser of the intermediate pressure column where it is partially vaporized to form a vapor and a liquid, a conduit for sending the vapor formed in the top condenser of the intermediate pressure column to the low pressure column, a conduit for sending the liquid from the top condenser of the intermediate pressure column to the intermediate pressure column to be separated, a conduit for sending a liquid from the bottom of the intermediate pressure column to the low pressure column and a conduit for sending a liquid from the top of the intermediate pressure column to the top of the low pressure column.
  • Preferably:
    • the intermediate pressure column has a bottom reboiler and the apparatus comprises a conduit for sending argon enriched gas from the low pressure column to be condensed in the bottom reboiler.
    • the liquid from the top condenser of the intermediate pressure column is sent to the intermediate pressure column between 2 and 5 theoretical trays above the bottom of the intermediate pressure column.
    • the apparatus comprises a compressor, a conduit for sending at least part of the air cooled to an intermediate temperature of the heat exchanger to the compressor, a conduit for sending air from the compressor to be further cooled in the heat exchanger and a conduit for sending the air from the compressor via the heat exchanger to at least the high pressure column.
    • the apparatus comprises a third pressurization means for pressurizing the liquid removed from the top condenser of the intermediate pressure column , before sending it to be separated in the intermediate pressure column.
  • Purified air has been treated to remove the water and carbon dioxide which it contains.
  • Oxygen rich liquid contains at least 70% mol. oxygen, preferably at least 85% mol. oxygen. It contains less than 100% mol. oxygen.
  • Nitrogen rich liquid contains at least 85% mol. nitrogen, preferably at least 90% mol nitrogen. It contains less than 100% moll nitrogen.
  • Oxygen enriched liquid contains at least 25% mol oxygen, or at least 30% mol oxygen.
  • For the present invention, the high pressure column operates at between 4 and 8 bar, the intermediate pressure column at between 2 and 3 bar, the argon column at between 1 and 2 bar, the low pressure column at between 1 and 2 bar.
  • All pressures mentioned are absolute pressures
  • The gaseous oxygen produced by pumping and vaporizing can be as low as 2 bar and as high as 80 bar or even 100 bars. The upper limit of the high pressure of pumped oxygen is usually dictated by the maximum allowable working pressure of the brazed heat exchanger.
  • The intermediate stream withdrawn from the high pressure column and sent to the intermediate pressure column top condenser contains between 18 and 25 mol% oxygen.
  • To illustrate the invention, Figure 1 shows the column portion of a process operating according to the invention and Figures 2 and 3 show two alternative corresponding heat exchanger portions, to be used for oxygen pressures above 15 bars abs.
  • In Figure 1, gaseous air 2 and liquid air 4 are fed to high pressure column 100. Oxygen enriched liquid 10 formed at the bottom of the high pressure column 100 is divided in two. One portion 12 is expanded and sent to an intermediate level of the low pressure column 101. Another portion 11 is expanded and sent to top condenser 105 of the argon column where it vaporizes to form stream 13 which is sent to the low pressure column 101. Alternatively all the oxygen enriched liquid 10 can be sent to the condenser 105 and partially condensed. In this case, stream 12 is absent and liquid from condenser 105 is sent to the low pressure column 101.The top of the high pressure column 100 is thermally coupled to the bottom of the low pressure column 101 via a condenser-reboiler 104. Nitrogen enriched liquid 40 from the top of the high pressure column 100 is divided in two, one portion 41 being sent to the top of the low pressure column 101 as reflux. Nitrogen enriched gas is removed from the top of the low pressure column 101.
  • A side liquid stream 20 with composition similar to air, containing between 18 and 25% mol. oxygen is extracted from column 100. Alternatively the side liquid stream could be replaced or supplemented by a part of liquid air stream 4 or another liquid air stream. A portion 22 of stream 20 (or stream 4, not illustrated) is partially vaporized in the top condenser 107 of intermediate pressure column 103. Condenser 107 could be a falling film vaporizer. The vapor 123 containing around 10% mol. oxygen) is sent to the low pressure column 101. A portion 24 of the liquid fraction 26 of the partially vaporization is then fed to column 103. Column 103 operates at about 2 bar and its condenser 107 at 1.4 bar. Gravity feed or a pump 110 can be used to transfer this liquid from condenser 107 to a position between 2 and 5 theoretical trays above the bottom of intermediate pressure column 103. Oxygen enriched liquid 60 from the bottom of column 103 containing preferably between 70 and 75 mol% oxygen is expanded and sent to the low pressure column. It is useful to note that a liquid air stream formed from the condensation of air for vaporizing liquid oxygen and liquid nitrogen products in the main heat exchanger can be sent to the top condenser of the intermediate column instead of using a part of the liquid stream 20 extracted from the high pressure column.
  • Preferably the average temperature difference for condensers 106, 107 should be between 0.8 and 0.9°C. Column 103 produces additional reflux liquid 23 for the top of the low pressure column 101. Column 102 is a typical side-arm argon column for a double column process. A portion 54 of argon enriched feed gas from the low pressure column 101 is separated in the argon column 102 to form argon product 80 in liquid form as shown or in gaseous form. The bottom liquid 52 from the argon column is sent back to the low pressure column 101. A portion 51 of argon enriched feed gas 50 from the low pressure column 101 is condensed in the bottom reboiler 106, preferably of the falling film type, of column 103 to yield liquid 53 which is then fed to column 102 or 101 to be separated. The argon column 102 is equipped with a top condenser 105 which vaporizes a portion 11 of oxygen enriched liquid 10 produced at the bottom of the high pressure column 100.
  • Another portion 45 of stream 40 is pumped by pump 121 to high pressure, vaporized and warmed to yield high pressure nitrogen product. Liquid oxygen 30 produced at the bottom of column 101 is pumped by pump 120 to high pressure, vaporized and warmed to yield high pressure oxygen product.
  • The embodiment shown in Figure 2 can be used to vaporize efficiently the liquid products 31, 42. The liquid products are vaporized in pumps 120,121, the oxygen being pressurized to a pressure between 15 and 80 bars abs. The cold compression technique is utilized and is described as follows:
    • Feed air compressed by compressor 201 to an elevated pressure of about between 15 and 25 bar is dried and its CO2 content is removed in the front end purification unit 208. The resulting dried and CO2 free stream 80 is divided into several portions. Portion 83 is cooled in heat exchanger 200 to an intermediate temperature thereof, a portion 91 of portion 83 is expanded in turboexpander 204 into the high pressure column 100. Second portion 84 of portion 83 is cold compressed, at a inlet temperature which is an intermediate temperature of the heat exchanger, in cold booster 202 to higher pressure to yield stream 85. Stream 85 is next cooled in exchanger 200 and liquefied to form liquid air stream 4. Another portion 79 of the cooled stream 83 is further cooled and liquefied to yield a second liquid air stream 6. Streams 4 and 6 are fed at least in part to the high pressure column 100 as feeds. A third portion 82 of feed air is further compressed in warm booster 207, cooled in exchanger 200 to yield cooled compressed stream 88 which is then expanded in turboexpander 203 into the high pressure column 100. The power generated by turboexpanders 203 and 204 can be used to drive boosters 202 and 207. Depending upon the pressure levels and the quantities of oxygen and nitrogen to be vaporized in the heat exchanger 200, it is sometime beneficial to also extract a portion of cooled compressed stream 88 and liquefy it in exchanger 200 in a similar fashion as stream 79. The resulting liquid stream (not shown) is then fed to the column system. By generating those auxiliary liquid streams, less liquid, i.e. lower flow, needs to be compressed by the cold compressor to satisfy the refrigeration balance at the cold end of the exchanger. More efficient system can be achieved by reducing the required cold compression flow.
  • The embodiment shown in Figure 3 can be used to reduce the plant power consumption. A multi stage booster compressor comprising several stages 209, 210 and 211 is added to further compress the fraction 82 feeding compressor 207. Multiple pressurized streams 95 and 96 can be generated by the booster compressor to vaporize efficiently the liquid products to form liquid air streams 97 and 99.
  • For lower oxygen pressures, more conventional vaporization processes such may be used. For very low pressures, the oxygen vaporizes in a dedicated vaporizer like a bath type vaporizer.
  • A cold booster has an inlet temperature of below -20°C.

Claims (15)

  1. Process for the separation of air by cryogenic distillation in a column system including a high pressure column (100), a low pressure column (101), the bottom of the low pressure column being thermally coupled with the top of the high pressure column, an intermediate pressure column (103), operating a pressure between that of the high pressure column and that of the low pressure column, and an argon column (102) wherein:
    i) purified compressed air is cooled in a heat exchanger (200) and sent at least in part to the high pressure column,
    ii) nitrogen enriched liquid (40, 41) is sent from the top of the high pressure column to the top of the low pressure column,
    iii) oxygen rich liquid (30) is removed from the low pressure column, pressurized and vaporized in the heat exchanger or another heat exchanger,
    iv) nitrogen rich liquid (42) is removed from the column system, pressurized and vaporized in the heat exchanger or another heat exchanger,
    v) argon enriched gas is sent from the low pressure column to the argon column, said argon column having a top condenser (105), and argon rich fluid (80) is removed from the top of the argon column,
    vi) oxygen enriched liquid (11) from the bottom of the high pressure column is partially vaporized in the top condenser of the argon column and the gas (13) thereby formed is sent to the low pressure column,
    vii) a liquid air stream (4) or a stream (20, 22) containing between 18 and 25 mol.% oxygen withdrawn from an intermediate point of the high pressure column is sent at least in part to a top condenser (107) of the intermediate pressure column where it is partially vaporized to form a vapor and a liquid,
    viii) the vapor (123) formed in the top condenser of the intermediate pressure column is sent to the low pressure column,
    ix) the liquid (24) from the top condenser of the intermediate pressure column is sent to the intermediate pressure column to be separated,
    x) a liquid (60) from the bottom of the intermediate pressure column is sent to the low pressure column, and
    xi) a liquid from the top of the intermediate pressure column (23) is sent to the top of the low pressure column.
  2. Process according to Claim 1 wherein the intermediate pressure column has a bottom reboiler (106) and wherein argon enriched gas (51) from the low pressure column is condensed in the bottom reboiler.
  3. Process according to Claim 1 or 2 wherein the liquid (24) sent from the top condenser of the intermediate pressure column is the only feed separated in the intermediate pressure column.
  4. Process according to any preceding claim wherein all the oxygen enriched liquid (10, 11, 12) from the high pressure column is sent to the argon column top condenser (105) or to the low pressure column and the argon column top condenser, without passing through the intermediate pressure column top condenser.
  5. Process according to any preceding claim wherein all the bottom liquid (60) of the intermediate pressure column is sent to the low pressure column without passing through the intermediate pressure column top condenser.
  6. Process according to any preceding claim wherein part (25) of the liquid from the intermediate pressure column top condenser (107) is sent to the low pressure column.
  7. Process according to any preceding claim wherein the liquid (24) from the top condenser is sent to the intermediate pressure column (103) between 2 and 5 theoretical trays above the bottom of the intermediate pressure column.
  8. Process according to any preceding claim wherein at least part of the air is cooled to an intermediate temperature of the heat exchanger (200), compressed in a compressor (202), further cooled in the heat exchanger and sent to at least the high pressure column (100).
  9. Process according to any preceding claim wherein the bottom liquid (60) of the intermediate pressure column (103) contains at least 70% mol. oxygen.
  10. Process according to any preceding claim wherein at least one of the bottom reboiler (106) and the top condenser (107) of the intermediate pressure column (103) is a falling film reboiler.
  11. Process according to any preceding claim wherein at least one part of the feed air is compressed from a first pressure to a second pressure in a warm booster (207) , fed to the heat exchanger at the second pressure, cooled, expanded in a first turboexpander (203) and sent to the high pressure column and at least another part of the feed air is sent to the heat exchanger at the first pressure, divided into three portions, the first portion being compressed from the first pressure to a third pressure in a cold booster (202), cooled, expanded and sent to the high pressure column, the second portion being expanded in a second turboexpander (204) and sent to the high pressure column and the third portion being cooled to the cold end of the heat exchanger and sent to the high pressure column.
  12. Apparatus for the separation of air by cryogenic distillation comprising a column system including a high pressure column (100), a low pressure column (101), the bottom of the low pressure column being thermally coupled with the top of the high pressure column, an intermediate pressure column (103), operating a pressure between that of the high pressure column and that of the low pressure column, and an argon column (102), a heat exchanger (200), a conduit for sending purified compressed air to be cooled in the heat exchanger, a conduit for sending cooled purified compressed air from the heat exchanger at least in part to the high pressure column, a conduit for sending nitrogen enriched liquid (40,41) from the top of the high pressure column to the top of the low pressure column, a conduit for removing oxygen rich liquid (30) from the low pressure column, said conduit being connected to first pressurization means (120), a conduit for sending pressurized oxygen rich liquid from the first pressurization means to the heat exchanger or another heat exchanger, a conduit for removing nitrogen rich liquid (40) from the column system connected to second pressurization means (121), a conduit connecting the second pressurization means to the heat exchanger or another heat exchanger, a conduit for sending argon enriched gas (50,54) from the low pressure column to the argon column, said argon column having a top condenser (105), a conduit for removing argon rich fluid (80) from the top of the argon column, a conduit for sending oxygen enriched liquid (10, 11) from the bottom of the high pressure column to the top condenser of the argon column to be partially vaporized, a conduit for sending the gas (13) thereby formed to the low pressure column, a conduit for sending a liquid air stream (4) or a liquid stream (20, 22) containing between 18 and 25% oxygen removed at an intermediate point of the high pressure column at least in part to a top condenser (107) of the intermediate pressure column where it is partially vaporized to form a vapor and a liquid, a conduit for sending the vapor (123) formed in the top condenser of the intermediate pressure column to the low pressure column, a conduit for sending the liquid (24) from the top condenser of the intermediate pressure column to the intermediate pressure column to be separated, a conduit for sending a liquid (60) from the bottom of the intermediate pressure column to the low pressure column and a conduit for sending a liquid (23) from the top of the intermediate pressure column to the top of the low pressure column.
  13. Apparatus according to Claim 12 wherein the intermediate pressure column (103) has a bottom reboiler (106) and comprising a conduit for sending argon enriched gas (51) from the low pressure column to be condensed in the bottom reboiler.
  14. Apparatus according to Claim 12 or 13 wherein the liquid (24) from the top condenser is sent to the intermediate pressure column (103) between 2 and 5 theoretical trays above the bottom of the intermediate pressure column.
  15. Apparatus according to any of Claims 12 to 14 comprising a compressor, a conduit for sending at least part of the air cooled to an intermediate temperature of the heat exchanger to the compressor (202), a conduit for sending air from the compressor to be further cooled in the heat exchanger and a conduit for sending the air from the compressor via the heat exchanger to at least the high pressure column.
EP11306552.8A 2011-11-24 2011-11-24 Process and apparatus for the separation of air by cryogenic distillation Not-in-force EP2597409B1 (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
EP11306552.8A EP2597409B1 (en) 2011-11-24 2011-11-24 Process and apparatus for the separation of air by cryogenic distillation
CN201280057446.7A CN103988036B (en) 2011-11-24 2012-09-26 For the method and apparatus by separating air by cryogenic distillation
PCT/EP2012/068948 WO2013075867A1 (en) 2011-11-24 2012-09-26 Process and apparatus for the separation of air by cryogenic distillation
US14/359,176 US20140318179A1 (en) 2011-11-24 2012-09-26 Process And Apparatus For The Separation Of Air By Cryogenic Distillation

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP11306552.8A EP2597409B1 (en) 2011-11-24 2011-11-24 Process and apparatus for the separation of air by cryogenic distillation

Publications (2)

Publication Number Publication Date
EP2597409A1 true EP2597409A1 (en) 2013-05-29
EP2597409B1 EP2597409B1 (en) 2015-01-14

Family

ID=46889069

Family Applications (1)

Application Number Title Priority Date Filing Date
EP11306552.8A Not-in-force EP2597409B1 (en) 2011-11-24 2011-11-24 Process and apparatus for the separation of air by cryogenic distillation

Country Status (4)

Country Link
US (1) US20140318179A1 (en)
EP (1) EP2597409B1 (en)
CN (1) CN103988036B (en)
WO (1) WO2013075867A1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR3010778A1 (en) * 2013-09-17 2015-03-20 Air Liquide PROCESS AND APPARATUS FOR PRODUCING GAS OXYGEN BY CRYOGENIC DISTILLATION OF AIR
EP2634517B1 (en) * 2012-02-29 2018-04-04 L'Air Liquide Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude Process and apparatus for the separation of air by cryogenic distillation

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
PL2963370T3 (en) * 2014-07-05 2018-11-30 Linde Aktiengesellschaft Method and device for the cryogenic decomposition of air
EP3067650B1 (en) * 2015-03-13 2018-04-25 Linde Aktiengesellschaft Installation and method for producing gaseous oxygen by cryogenic air decomposition
CN107580670B (en) * 2015-03-13 2020-02-28 林德股份公司 Apparatus for producing oxygen by cryogenic air separation
KR101854623B1 (en) 2016-06-15 2018-05-04 베니트엠 주식회사 Method for regenerating ammonium bicarbonate solution
JP7355978B2 (en) * 2019-04-08 2023-10-04 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 Cryogenic air separation equipment
US12078415B2 (en) * 2019-07-26 2024-09-03 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Process and apparatus for the separation of air by cryogenic distillation
JP7495675B2 (en) * 2019-09-18 2024-06-05 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 High Purity Oxygen Production System
EP4151940A1 (en) * 2021-09-18 2023-03-22 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Method and apparatus for cryogenic air separation

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0828123A2 (en) 1996-09-05 1998-03-11 The Boc Group Plc Air separation
EP1055891A1 (en) * 1999-05-25 2000-11-29 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Cryogenic distillation system for air separation
DE10061908A1 (en) * 2000-12-12 2002-06-27 Messer Ags Gmbh Device for low temperature decomposition of air, for recovery of nitrogen, oxygen and argon, comprises two-stage rectifier column comprising high pressure column

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5689975A (en) * 1995-10-11 1997-11-25 The Boc Group Plc Air separation
US5966967A (en) * 1998-01-22 1999-10-19 Air Products And Chemicals, Inc. Efficient process to produce oxygen
US5956974A (en) * 1998-01-22 1999-09-28 Air Products And Chemicals, Inc. Multiple expander process to produce oxygen
FR2814229B1 (en) * 2000-09-19 2002-10-25 Air Liquide METHOD AND PLANT FOR AIR SEPARATION BY CRYOGENIC DISTILLATION
DE10113790A1 (en) * 2001-03-21 2002-09-26 Linde Ag Three-column system for low-temperature air separation
US9222725B2 (en) * 2007-06-15 2015-12-29 Praxair Technology, Inc. Air separation method and apparatus
FR2948184B1 (en) * 2009-07-20 2016-04-15 Air Liquide METHOD AND APPARATUS FOR AIR SEPARATION BY CRYOGENIC DISTILLATION
US8899075B2 (en) * 2010-11-18 2014-12-02 Praxair Technology, Inc. Air separation method and apparatus

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0828123A2 (en) 1996-09-05 1998-03-11 The Boc Group Plc Air separation
EP1055891A1 (en) * 1999-05-25 2000-11-29 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Cryogenic distillation system for air separation
DE10061908A1 (en) * 2000-12-12 2002-06-27 Messer Ags Gmbh Device for low temperature decomposition of air, for recovery of nitrogen, oxygen and argon, comprises two-stage rectifier column comprising high pressure column

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
ANONYMOUS: "Intermediate pressure column in air separation", RESEARCH DISCLOSURE, MASON PUBLICATIONS, HAMPSHIRE, GB, vol. 425, no. 44, 1 September 1999 (1999-09-01), XP007124790, ISSN: 0374-4353 *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2634517B1 (en) * 2012-02-29 2018-04-04 L'Air Liquide Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude Process and apparatus for the separation of air by cryogenic distillation
FR3010778A1 (en) * 2013-09-17 2015-03-20 Air Liquide PROCESS AND APPARATUS FOR PRODUCING GAS OXYGEN BY CRYOGENIC DISTILLATION OF AIR
WO2015040306A3 (en) * 2013-09-17 2015-06-11 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Process and apparatus for producing gaseous oxygen by cryogenic distillation of air
US9976803B2 (en) 2013-09-17 2018-05-22 L'air Liquide Societe Anonyme Pour L'etude Et L'exploitattion Des Procedes Georges Claude Process and apparatus for producing gaseous oxygen by cryogenic distillation of air

Also Published As

Publication number Publication date
WO2013075867A1 (en) 2013-05-30
EP2597409B1 (en) 2015-01-14
US20140318179A1 (en) 2014-10-30
CN103988036A (en) 2014-08-13
CN103988036B (en) 2016-02-10

Similar Documents

Publication Publication Date Title
EP2597409B1 (en) Process and apparatus for the separation of air by cryogenic distillation
EP1782011B1 (en) Low temperature air separation process for producing pressurized gaseous product
US8695377B2 (en) Process and apparatus for the separation of air by cryogenic distillation
EP1972875A1 (en) Process and apparatus for the separation of air by cryogenic distillation
US20050126221A1 (en) Process and apparatus for the separation of air by cryogenic distillation
EP0877217B2 (en) Cryogenic air separation with warm turbine recycle
JP3556914B2 (en) Air separation method and air separation device using the same
EP2634517B1 (en) Process and apparatus for the separation of air by cryogenic distillation
NO174684B (en) Process for the production of nitrogen by distillation of air
US20080223075A1 (en) Process and Apparatus for the Separation of Air by Cryogenic Distillation
US6347534B1 (en) Cryogenic distillation system for air separation
US6202441B1 (en) Cryogenic distillation system for air separation
US6196024B1 (en) Cryogenic distillation system for air separation
US6276170B1 (en) Cryogenic distillation system for air separation
US6318120B1 (en) Cryogenic distillation system for air separation

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

AX Request for extension of the european patent

Extension state: BA ME

17P Request for examination filed

Effective date: 20131129

RBV Designated contracting states (corrected)

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

INTG Intention to grant announced

Effective date: 20140814

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

REG Reference to a national code

Ref country code: CH

Ref legal event code: EP

REG Reference to a national code

Ref country code: IE

Ref legal event code: FG4D

REG Reference to a national code

Ref country code: AT

Ref legal event code: REF

Ref document number: 707277

Country of ref document: AT

Kind code of ref document: T

Effective date: 20150215

REG Reference to a national code

Ref country code: DE

Ref legal event code: R096

Ref document number: 602011013108

Country of ref document: DE

Effective date: 20150226

REG Reference to a national code

Ref country code: NL

Ref legal event code: VDEP

Effective date: 20150114

REG Reference to a national code

Ref country code: AT

Ref legal event code: MK05

Ref document number: 707277

Country of ref document: AT

Kind code of ref document: T

Effective date: 20150114

REG Reference to a national code

Ref country code: LT

Ref legal event code: MG4D

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20150114

Ref country code: LT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20150114

Ref country code: FI

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20150114

Ref country code: NO

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20150414

Ref country code: HR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20150114

Ref country code: ES

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20150114

Ref country code: BG

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20150414

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: RS

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20150114

Ref country code: IS

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20150514

Ref country code: NL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20150114

Ref country code: PL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20150114

Ref country code: LV

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20150114

Ref country code: AT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20150114

Ref country code: GR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20150415

REG Reference to a national code

Ref country code: DE

Ref legal event code: R097

Ref document number: 602011013108

Country of ref document: DE

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20150114

Ref country code: DK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20150114

Ref country code: RO

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20150114

Ref country code: EE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20150114

Ref country code: CZ

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20150114

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 5

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed

Effective date: 20151015

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20150114

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SI

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20150114

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: BE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20150114

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: MC

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20150114

Ref country code: LU

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20151124

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: CH

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20151130

Ref country code: LI

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20151130

REG Reference to a national code

Ref country code: IE

Ref legal event code: MM4A

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20151124

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 6

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: HU

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT; INVALID AB INITIO

Effective date: 20111124

Ref country code: SM

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20150114

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: CY

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20150114

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: MT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20150114

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 7

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: TR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20150114

Ref country code: MK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20150114

Ref country code: PT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20150114

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: AL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20150114

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20181120

Year of fee payment: 8

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20181120

Year of fee payment: 8

Ref country code: FR

Payment date: 20181123

Year of fee payment: 8

REG Reference to a national code

Ref country code: DE

Ref legal event code: R119

Ref document number: 602011013108

Country of ref document: DE

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20191124

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20191124

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20200603

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20191202