EP2741036A1 - 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
EP2741036A1
EP2741036A1 EP12306527.8A EP12306527A EP2741036A1 EP 2741036 A1 EP2741036 A1 EP 2741036A1 EP 12306527 A EP12306527 A EP 12306527A EP 2741036 A1 EP2741036 A1 EP 2741036A1
Authority
EP
European Patent Office
Prior art keywords
column
nitrogen
turboexpander
rich gas
heat exchanger
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.)
Withdrawn
Application number
EP12306527.8A
Other languages
German (de)
French (fr)
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 EP12306527.8A priority Critical patent/EP2741036A1/en
Publication of EP2741036A1 publication Critical patent/EP2741036A1/en
Withdrawn legal-status Critical Current

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
    • 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
    • F25J3/04048—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
    • F25J3/0406—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 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
    • F25J3/04248—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
    • F25J3/04284—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
    • F25J3/04309—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 nitrogen
    • F25J3/04315—Lowest pressure or impure nitrogen, so-called waste nitrogen 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
    • F25J3/04248—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.
    • F25J3/04387—Details relating to the work expansion, e.g. process parameter etc. using liquid or hydraulic turbine 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
    • F25J3/04248—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
    • 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
    • F25J2205/00—Processes or apparatus using other separation and/or other processing means
    • F25J2205/02—Processes or apparatus using other separation and/or other processing means using simple phase separation in a vessel or drum
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2235/00—Processes or apparatus involving steps for increasing the pressure or for conveying of liquid process streams
    • F25J2235/42—Processes or apparatus involving steps for increasing the pressure or for conveying of liquid process streams the fluid being 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
    • F25J2240/00—Processes or apparatus involving steps for expanding of process streams
    • F25J2240/02—Expansion of a process fluid in a work-extracting turbine (i.e. isentropic expansion), e.g. of the feed stream
    • F25J2240/10—Expansion of a process fluid in a work-extracting turbine (i.e. isentropic expansion), e.g. of the feed stream the fluid being air
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2245/00—Processes or apparatus involving steps for recycling of process streams
    • F25J2245/42—Processes or apparatus involving steps for recycling of process streams the recycled stream being 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
    • F25J2290/00—Other details not covered by groups F25J2200/00 - F25J2280/00
    • F25J2290/12—Particular process parameters like pressure, temperature, ratios

Definitions

  • the present invention relates to a process and apparatus for the separation of air by cryogenic distillation.
  • the Integrated Gasifier Combined Cycle is usually selected to generate clean energy from coal. This clean energy production technique is especially suited for new coal-based power generation projects specified to operate efficiently and with minimal pollution to the environment.
  • the air separation unit ASU for the IGCC is a combination of an oxygen plant and a nitrogen generator plant.
  • the air separation process frequently used for this type of application is the "elevated pressure" process ie with a low pressure operating at at least 2 bars abs, preferably at least 3 bars abs.
  • An object of the present invention is to provide an air separation unit with reduced energy consumption but which is capable of producing nitrogen and oxygen with a nitrogen/oxygen ratio of 3.6 or less, preferably less than 2.9.
  • the nitrogen/oxygen ratio is defined as the total of nitrogen flow divided by the total of oxygen flow.
  • a process for the separation of air by cryogenic distillation in which air is purified, cooled in a heat exchanger and separated in a column system including at least a first column, a second column and a third column, the first column operating at a higher pressure than the second column, the second column operating at at least 2 bars abs, preferably at at least 4 bars abs, the third column operating at a pressure intermediate to the pressures of first and second columns and the top of the first column being thermally linked to the bottom of the second column via a first reboiler-condenser, oxygen enriched liquid is removed from the first column and sent to the third column, oxygen enriched liquid from the bottom of the third column is sent to the second column, nitrogen enriched liquid from the top of the third column is sent to the second column, nitrogen enriched liquid is removed from the first column and sent to the second column, oxygen rich liquid is removed from the second column, pressurized and vaporized in the heat exchanger to form an oxygen rich gas, nitrogen rich fluid is
  • an apparatus for the separation of air by cryogenic distillation comprising column system including at least a first column, a second column and a third column, the first column operating at a higher pressure than the second column" the third column operating at a pressure between that of the first column and that of the second column, the second column operating at least 2 bars abs and the top of the first column being thermally linked to the bottom of the second column via a first reboiler-condenser, a heat exchanger, a compressor, a turboexpander, purification means for purifying air, means for sending purified air to the heat exchanger to be cooled, means for sending cooled purified air to the first column, a conduit for sending an oxygen enriched liquid from the first column to the third column, a conduit for sending oxygen enriched liquid from the bottom of the third column to the second column , a conduit for sending nitrogen enriched liquid from the top of the third column to the second column, a conduit for removing nitrogen enriched liquid from the first
  • the apparatus may comprise:
  • FIG. 1 a cryogenic air separation process using a standard double column equipped with an intermediate column 300, having a first column 100 operating at between 12 and 17 bars abs and a second column 200 operating at between 4 and 6 bars abs, the first column operating at a higher pressure than the second column and being placed below the second column.
  • the top of the first column 11 is thermally linked to the bottom of the second column 15 by means of a vaporizer-condenser 70.
  • the intermediate column 300 operates at a pressure between the pressures of columns 100 and 200.
  • an air stream 1 of 1000 Nm 3 /h at 15.8 bars (ie compressed to the operating pressure of the first column 100) is divided into two parts.
  • One part 4 is cooled in heat exchanger 400 and sent in gaseous form to the first column 100.
  • the other part 2 (400 Nm 3 /h) is boosted to a higher pressure of 44 bars abs by booster compressor 94 and sent to the heat exchanger 400.
  • One part 3 of the boosted air at 44 bars abs is cooled to an intermediate temperature of the heat exchanger 400, removed from the heat exchanger, compressed in cold compressor 93, cooled and expanded and sent as a liquid stream to column 100.
  • the other part 12 is further boosted in booster 95, cooled in the heat exchanger 400, to an intermediate temperature thereof, expanded in turboexpander 92 as stream 15 and sent to the first column 100 after expansion in gaseous form.
  • the inlet temperature of the cold compressor 93 is warmer than the inlet temperature of turboexpanders 91, 92.
  • Oxygen enriched liquid 10 from the bottom of the first column 100 is expanded in a valve and sent to a third column 300 operating at a pressure between the pressure of the first column and the pressure of the second column 200.
  • the oxygen enriched liquid is separated in the third column forming a bottom liquid further enriched in oxygen 31. Part of this liquid is sent as stream 34 to the top condenser 72 of the third column 300 after expansion in a valve.
  • the vaporized liquid 36 is then sent to the second column 200.
  • the rest 35 is expanded in a valve and sent to the second column 200.
  • An intermediate liquid stream 20 is removed from the first column 100, expanded and sent to the second column 200.
  • Nitrogen enriched liquid 40 from the top of the first column is expanded in a valve and sent to the top of the second column 200.
  • Nitrogen enriched gas from the top of the first column is used to heat bottom reboiler 71 of the third column 300.
  • the liquid produced is sent in part back to the top of the first column 100 and in part as part of stream 40 to the top of the second column.
  • Nitrogen enriched liquid 44 from the top of the third column 300 is expanded and sent to the top of the second column 200.
  • the column system produces a high pressure gaseous oxygen stream 51 by removing liquid oxygen 30 containing at least 80% mol oxygen (in this example 210 Nm 3 /h oxygen at 95% mol oxygen) from the bottom of second column 200, pressurizing it via pump 90 and vaporizing the pumped liquid in exchanger 400. This produces a stream at 67 bars abs.
  • the column system produces a gaseous nitrogen stream 50 at 15.35 bars abs by removing gaseous nitrogen 42 from the top of column 100 and warming it in exchanger 400.
  • Nitrogen rich gas 60 from the top of the second column 200 is warmed in a heat exchanger (not shown) to yield stream 26, a portion 27 is expanded in turboexpander 99 to low pressure close to atmospheric pressure to yield stream 28, which can be partially liquefied, then sent to phase separator 97.
  • the remaining portion 24 of stream 26 is warmed in exchanger 400,to an intermediate temperature and sent as stream 23 to a cold compressor 96, which compresses the nitrogen rich gas to higher pressure as stream 22.
  • the compressed nitrogen rich gas is removed as nitrogen product 53 at about 5 bars abs.
  • the vapor stream 62 from separator 97 is warmed in exchanger 400 and exits the process as a waste or vented low pressure nitrogen 52.
  • the liquid fraction 29 (if it exists) can be pumped by pump 98 and sent to the top of column 200 as additional reflux.
  • the energy generated by expander 99 can be used to drive the compressor 96.
  • Stream 51 may be sent to a gasifier.
  • the ratio between the amount of nitrogen rich gas produced (total of 50 and 53) and the amount of oxygen rich gas 51 produced is less than 3, less than 2.5, or even less than 2,
  • the combination of the turboexpander 99 for expansion of the excess nitrogen and the cold nitrogen compressor allows the produced nitrogen pressure to be increased. This can reduce the number of nitrogen compressor stages required if the product nitrogen is to be compressed to a higher pressure.
  • By adjusting the expanded flow in expander 99 the flow and pressure of the nitrogen product portion 53 can be adapted to satisfy the required nitrogen/oxygen ratio.
  • the process efficiency can be maintained by recovering the energy of the expander 99 to drive the compressor 96 to increase the product pressure of stream 53.
  • Either the cold nitrogen compressor 96 or the cold air compressor 93 must be present, but not necessarily both.
  • the invention could in theory also be applied to a double column without any intermediate pressure column, however to produce low purity oxygen at around 95% purity, the low pressure column would need to operate at around 2 to 2.5 bars. In this case, the nitrogen expander ratio would be very low (from 1.5 to 1.9) and so power recovery would not be optimal.
  • the present invention is consequently reduced to the triple column case where the low pressure column operates at at least 4 bars abs, so as to have a nitrogen expansion ratio which is higher than in the double column case and therefore more suitable for power recovery.

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

In a process for the separation of air by cryogenic distillation in a triple column (100, 200, 300), the ratio between the amount of nitrogen rich gas produced and the amount of oxygen rich gas produced, is less than 3 or even less than 2.5 and a second nitrogen rich gas removed from the column system is expanded in a turboexpander (99) having an inlet temperature lower than the ambient temperature, the turboexpander being driven by a cold compressor (96).

Description

  • The present invention relates to a process and apparatus for the separation of air by cryogenic distillation.
  • The Integrated Gasifier Combined Cycle is usually selected to generate clean energy from coal. This clean energy production technique is especially suited for new coal-based power generation projects specified to operate efficiently and with minimal pollution to the environment.
  • To gasify the coal for the IGCC, impure high pressure oxygen is used. In addition, nitrogen is generally required in a relatively pure state at quite high pressure in the combustion of the synthesis gas in the gas turbine to dilute the synthesis gas or hydrogen produced during the gasification process, so as to reduce the nitrous oxides (NOx) emission levels.
  • To produce oxygen for an IGCC plant, three well known techniques used in the context are:
    • producing the oxygen in an independent ASU (air separation unit),
    • taking air for the ASU from the gas turbine compressor,
    • taking part of the air for the ASU from the gas turbine compressor and using a dedicated compressor to produce the rest.
  • The types of gasification or gas turbine would dictate the required quantity of nitrogen to be used in the IGCC complex. It can be seen from this characteristic that the air separation unit ASU for the IGCC is a combination of an oxygen plant and a nitrogen generator plant.
  • The air separation process frequently used for this type of application is the "elevated pressure" process ie with a low pressure operating at at least 2 bars abs, preferably at least 3 bars abs.
  • Although air separation units operating with this concept have good energy efficiency and reduced power consumption, it is not always possible to use this sort of ASU because it is necessary to reach this high efficiency that the nitrogen/oxygen ratio is very close to that found for air, ie close to 3.6. If the required ratio is lower than this value, for example about 2.5, the power consumption of such a plant is higher that in the case of a conventional "low pressure" process because part of the elevated pressure nitrogen product is not fully utilized and either must be vented or depressurized.
  • It is known from EP-A-0518491 to take nitrogen from a low pressure column and expand it at a low temperature to produce liquid nitrogen. If liquid nitrogen is not required then this approach cannot be used.
  • An object of the present invention is to provide an air separation unit with reduced energy consumption but which is capable of producing nitrogen and oxygen with a nitrogen/oxygen ratio of 3.6 or less, preferably less than 2.9.
  • Since nitrogen or oxygen can be extracted from one or several columns of the process, the nitrogen/oxygen ratio is defined as the total of nitrogen flow divided by the total of oxygen flow.
  • According to an object of the invention, there is provided a process for the separation of air by cryogenic distillation in which air is purified, cooled in a heat exchanger and separated in a column system including at least a first column, a second column and a third column, the first column operating at a higher pressure than the second column, the second column operating at at least 2 bars abs, preferably at at least 4 bars abs, the third column operating at a pressure intermediate to the pressures of first and second columns and the top of the first column being thermally linked to the bottom of the second column via a first reboiler-condenser, oxygen enriched liquid is removed from the first column and sent to the third column, oxygen enriched liquid from the bottom of the third column is sent to the second column, nitrogen enriched liquid from the top of the third column is sent to the second column, nitrogen enriched liquid is removed from the first column and sent to the second column, oxygen rich liquid is removed from the second column, pressurized and vaporized in the heat exchanger to form an oxygen rich gas, nitrogen rich fluid is removed from the column system and warmed in the heat exchanger to form a first nitrogen rich gas, wherein the product ratio, being the ratio between the amount of nitrogen rich gas produced and the amount of oxygen rich gas produced, is less than 3.6 or even less than 2.5 and a second nitrogen rich gas removed from the second column is expanded in a turboexpander having an inlet/outlet pressure ratio of at least 2, or even at least 3, said turboexpander having an inlet temperature lower than the ambient temperature.
  • According to further optional aspects of the invention
    • a nitrogen rich gas removed from the column system or an air stream is compressed in a compressor driven by the turboexpander and having an inlet temperature less than -20°C.
    • the nitrogen rich gas is removed from the second column and divided in two, one part being sent to the compressor and the other part being expanded in the turboexpander.
    • the nitrogen rich gas is expanded in the turboexpander without having been warmed.
    • the product ratio is less than 2.
    • the turboexpander has an inlet temperature of at most -50°C, preferably of at most -100°C.
    • during the second period, the outlet pressure of the turboexpander is substantially equal to the pressure of the second column.
    • gas from the phase separator is sent to the heat exchanger.
    • the compressor is driven by the turboexpander.
    • nitrogen enriched liquid is sent to a phase separator from the outlet of the turboexpander and gas is removed from the phase separator.
    • liquid from the phase separator is sent back to the column system to be separated.
  • According to a further aspect of the invention, there is provided an apparatus for the separation of air by cryogenic distillation comprising column system including at least a first column, a second column and a third column, the first column operating at a higher pressure than the second column" the third column operating at a pressure between that of the first column and that of the second column, the second column operating at least 2 bars abs and the top of the first column being thermally linked to the bottom of the second column via a first reboiler-condenser, a heat exchanger, a compressor, a turboexpander, purification means for purifying air, means for sending purified air to the heat exchanger to be cooled, means for sending cooled purified air to the first column, a conduit for sending an oxygen enriched liquid from the first column to the third column, a conduit for sending oxygen enriched liquid from the bottom of the third column to the second column , a conduit for sending nitrogen enriched liquid from the top of the third column to the second column, a conduit for removing nitrogen enriched liquid from the first column and sending it to the second column, a conduit for removing oxygen rich liquid from the second column, to be pressurized and vaporized in the heat exchanger to form an oxygen rich gas, a conduit for removing nitrogen rich fluid from the column system to be warmed in the heat exchanger to form a first nitrogen rich gas, wherein the product ratio, being the ratio between the amount of nitrogen rich gas produced and the amount of oxygen rich gas produced, is less than 3.6, less than 3 or even less than 2.5 and a conduit for removing a second nitrogen rich gas and sending it to the turboexpander having an inlet temperature lower than the ambient temperature and upstream of the heat exchanger, a phase separator, a conduit for sending nitrogen enriched liquid to the phase separator from the outlet of the turboexpander and a conduit for removing nitrogen enriched gas from the phase separator,
  • According to further optional features, the apparatus may comprise:
    • means for sending nitrogen enriched gas to the compressor, the nitrogen enriched gas being removed either directly from the column system or after warming in the heat exchanger, the compressor being coupled to the turboexpander.
    • pressurizing means for pressurizing the nitrogen enriched liquid and a conduit for sending the pressurized nitrogen enriched liquid to the column system.
  • The invention will be described in greater detail with reference to Figure 1 which represents a process according to the invention.
  • In Figure 1, a cryogenic air separation process using a standard double column equipped with an intermediate column 300, having a first column 100 operating at between 12 and 17 bars abs and a second column 200 operating at between 4 and 6 bars abs, the first column operating at a higher pressure than the second column and being placed below the second column. The top of the first column 11 is thermally linked to the bottom of the second column 15 by means of a vaporizer-condenser 70. The intermediate column 300 operates at a pressure between the pressures of columns 100 and 200.
  • When the process is in operation, an air stream 1 of 1000 Nm3/h at 15.8 bars (ie compressed to the operating pressure of the first column 100) is divided into two parts. One part 4 is cooled in heat exchanger 400 and sent in gaseous form to the first column 100. The other part 2 (400 Nm3/h) is boosted to a higher pressure of 44 bars abs by booster compressor 94 and sent to the heat exchanger 400. One part 3 of the boosted air at 44 bars abs is cooled to an intermediate temperature of the heat exchanger 400, removed from the heat exchanger, compressed in cold compressor 93, cooled and expanded and sent as a liquid stream to column 100. Another part 5 of the boosted air cooled to an intermediate temperature of the heat exchanger 400, expanded in turboexpander 91 as stream 16 and sent to column 100 in gaseous form. The other part 12 is further boosted in booster 95, cooled in the heat exchanger 400, to an intermediate temperature thereof, expanded in turboexpander 92 as stream 15 and sent to the first column 100 after expansion in gaseous form.
  • The inlet temperature of the cold compressor 93 is warmer than the inlet temperature of turboexpanders 91, 92.
  • Oxygen enriched liquid 10 from the bottom of the first column 100 is expanded in a valve and sent to a third column 300 operating at a pressure between the pressure of the first column and the pressure of the second column 200. The oxygen enriched liquid is separated in the third column forming a bottom liquid further enriched in oxygen 31. Part of this liquid is sent as stream 34 to the top condenser 72 of the third column 300 after expansion in a valve. The vaporized liquid 36 is then sent to the second column 200. The rest 35 is expanded in a valve and sent to the second column 200.
  • An intermediate liquid stream 20 is removed from the first column 100, expanded and sent to the second column 200.
  • Nitrogen enriched liquid 40 from the top of the first column is expanded in a valve and sent to the top of the second column 200.
  • Nitrogen enriched gas from the top of the first column is used to heat bottom reboiler 71 of the third column 300. The liquid produced is sent in part back to the top of the first column 100 and in part as part of stream 40 to the top of the second column.
  • Nitrogen enriched liquid 44 from the top of the third column 300 is expanded and sent to the top of the second column 200.
  • The column system produces a high pressure gaseous oxygen stream 51 by removing liquid oxygen 30 containing at least 80% mol oxygen (in this example 210 Nm3/h oxygen at 95% mol oxygen) from the bottom of second column 200, pressurizing it via pump 90 and vaporizing the pumped liquid in exchanger 400. This produces a stream at 67 bars abs.
  • The column system produces a gaseous nitrogen stream 50 at 15.35 bars abs by removing gaseous nitrogen 42 from the top of column 100 and warming it in exchanger 400.
  • Nitrogen rich gas 60 from the top of the second column 200 is warmed in a heat exchanger (not shown) to yield stream 26, a portion 27 is expanded in turboexpander 99 to low pressure close to atmospheric pressure to yield stream 28, which can be partially liquefied, then sent to phase separator 97. The remaining portion 24 of stream 26 is warmed in exchanger 400,to an intermediate temperature and sent as stream 23 to a cold compressor 96, which compresses the nitrogen rich gas to higher pressure as stream 22. The compressed nitrogen rich gas is removed as nitrogen product 53 at about 5 bars abs. The vapor stream 62 from separator 97 is warmed in exchanger 400 and exits the process as a waste or vented low pressure nitrogen 52. The liquid fraction 29 (if it exists) can be pumped by pump 98 and sent to the top of column 200 as additional reflux. The energy generated by expander 99 can be used to drive the compressor 96.
  • Stream 51 may be sent to a gasifier.
  • The ratio between the amount of nitrogen rich gas produced (total of 50 and 53) and the amount of oxygen rich gas 51 produced (known as the "product ratio"), is less than 3, less than 2.5, or even less than 2, The combination of the turboexpander 99 for expansion of the excess nitrogen and the cold nitrogen compressor allows the produced nitrogen pressure to be increased. This can reduce the number of nitrogen compressor stages required if the product nitrogen is to be compressed to a higher pressure. By adjusting the expanded flow in expander 99 the flow and pressure of the nitrogen product portion 53 can be adapted to satisfy the required nitrogen/oxygen ratio. The process efficiency can be maintained by recovering the energy of the expander 99 to drive the compressor 96 to increase the product pressure of stream 53.
  • Either the cold nitrogen compressor 96 or the cold air compressor 93 must be present, but not necessarily both.
  • The invention could in theory also be applied to a double column without any intermediate pressure column, however to produce low purity oxygen at around 95% purity, the low pressure column would need to operate at around 2 to 2.5 bars. In this case, the nitrogen expander ratio would be very low (from 1.5 to 1.9) and so power recovery would not be optimal.
  • The present invention is consequently reduced to the triple column case where the low pressure column operates at at least 4 bars abs, so as to have a nitrogen expansion ratio which is higher than in the double column case and therefore more suitable for power recovery.

Claims (14)

  1. Process for the separation of air by cryogenic distillation in which air is purified, cooled in a heat exchanger (400) and separated in a column system including at least a first column (100), a second column (200) and a third column (300), the first column operating at a higher pressure than the second column, the second column operating at at least 2 bars abs, preferably at at least 4 bars abs, the third column operating at a pressure intermediate to the pressures of first and second columns and the top of the first column being thermally linked to the bottom of the second column via a first reboiler-condenser (70), oxygen enriched liquid (10) is removed from the first column and sent to the third column, oxygen enriched liquid (31) from the bottom of the third column is sent to the second column, nitrogen enriched liquid (44) from the top of the third column is sent to the second column, nitrogen enriched liquid (20) is removed from the first column and sent to the second column, oxygen rich liquid (30) is removed from the second column, pressurized and vaporized in the heat exchanger to form an oxygen rich gas, nitrogen rich fluid (24) is removed from the column system and warmed in the heat exchanger to form a first nitrogen rich gas, wherein the product ratio, being the ratio between the amount of nitrogen rich gas produced (50, 52, 53) and the amount of oxygen rich gas (51) produced, is less than 3.6 or even less than 2.5 and a second nitrogen rich gas (27) removed from the second column is expanded in a turboexpander (99) having an inlet/outlet pressure ratio of at least 2, or even at least 3, said turboexpander having an inlet temperature lower than the ambient temperature.
  2. Process according to Claim 1 wherein a nitrogen rich gas removed from the column system or an air stream is compressed in a compressor (96) driven by the turboexpander (99) and having an inlet temperature less than -20°C.
  3. Process according to Claim 2 wherein the nitrogen rich gas (60) is removed from the second column and divided in two, one part (24) being sent to the compressor (96) and the other part (27) being expanded in the turboexpander (99).
  4. Process according to any preceding claim wherein the nitrogen rich gas is expanded in the turboexpander (99) without having been warmed.
  5. Process according to any preceding claim wherein the product ratio is less than 2.
  6. Process according to any preceding claim wherein the turboexpander (99) has an inlet temperature of at most -50°C, preferably of at most -100°C.
  7. Process according to any preceding claim wherein during the second period, the outlet pressure of the turboexpander (99) is substantially equal to the pressure of the second column.
  8. Process according to any preceding claim wherein gas is sent from the turboexpander (99) to a phase separator (97) and gas from the phase separator (97) is sent to the heat exchanger.
  9. Process according to any preceding claim wherein the compressor is driven by the turboexpander.
  10. Process according to any preceding claim wherein nitrogen enriched liquid is sent to a phase separator (97) from the outlet of the turboexpander and gas (62) is removed from the phase separator.
  11. Process according to Claim 10 wherein liquid (29, 46) from the phase separator (97) is sent back to the column system to be separated.
  12. Apparatus for the separation of air by cryogenic distillation comprising column system including at least a first column (100), a second column (200) and a third column (300), the first column operating at a higher pressure than the second column" the third column operating at a pressure between that of the first column and that of the second column, the second column operating at least 2 bars abs and the top of the first column being thermally linked to the bottom of the second column via a first reboiler-condenser (70), a heat exchanger (400), a compressor (96), a turboexpander (99), purification means for purifying air, means for sending purified air to the heat exchanger to be cooled, means for sending cooled purified air to the first column, a conduit for sending an oxygen enriched liquid from the first column to the third column, a conduit for sending oxygen enriched liquid from the bottom of the third column to the second column , a conduit for sending nitrogen enriched liquid from the top of the third column to the second column, a conduit for removing nitrogen enriched liquid from the first column and sending it to the second column, a conduit for removing oxygen rich liquid from the second column, to be pressurized and vaporized in the heat exchanger to form an oxygen rich gas, a conduit for removing nitrogen rich fluid from the column system to be warmed in the heat exchanger to form a first nitrogen rich gas, wherein the product ratio, being the ratio between the amount of nitrogen rich gas produced and the amount of oxygen rich gas produced, is less than 3.6, less than 3 or even less than 2.5 and a conduit for removing a second nitrogen rich gas and sending it to the turboexpander having an inlet temperature lower than the ambient temperature and upstream of the heat exchanger, a phase separator, a conduit for sending nitrogen enriched liquid to the phase separator from the outlet of the turboexpander and a conduit for removing nitrogen enriched gas from the phase separator.
  13. Apparatus according to Claim 13 comprising means for sending nitrogen enriched gas to the compressor (96), the nitrogen enriched gas being removed either directly from the column system or after warming in the heat exchanger, the compressor being coupled to the turboexpander (99).
  14. Apparatus according to Claim 13 or 14 comprising pressurizing means (98) for pressurizing the nitrogen enriched liquid from the phase separator (97) and a conduit for sending the pressurized nitrogen enriched liquid to the column system.
EP12306527.8A 2012-12-06 2012-12-06 Process and apparatus for the separation of air by cryogenic distillation Withdrawn EP2741036A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP12306527.8A EP2741036A1 (en) 2012-12-06 2012-12-06 Process and apparatus for the separation of air by cryogenic distillation

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP12306527.8A EP2741036A1 (en) 2012-12-06 2012-12-06 Process and apparatus for the separation of air by cryogenic distillation

Publications (1)

Publication Number Publication Date
EP2741036A1 true EP2741036A1 (en) 2014-06-11

Family

ID=47713781

Family Applications (1)

Application Number Title Priority Date Filing Date
EP12306527.8A Withdrawn EP2741036A1 (en) 2012-12-06 2012-12-06 Process and apparatus for the separation of air by cryogenic distillation

Country Status (1)

Country Link
EP (1) EP2741036A1 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107166872A (en) * 2017-04-27 2017-09-15 杭州颐氧健康科技有限公司 Health care gas deep cooling auto-pressurizing device for making and its method
US20220090856A1 (en) * 2020-09-21 2022-03-24 L'air Liquide, Societe Anonyme Pour L'etude Et L?Exploitation Des Procedes Georges Claude Apparatus for the separation of air by cryogenic distillation comprising three columns, including two concentric columns
CN115092891A (en) * 2022-05-16 2022-09-23 西安交通大学 Oxygen generator suitable for plateau environment and method

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0518491A1 (en) 1991-05-14 1992-12-16 Air Products And Chemicals, Inc. Elevated pressure air separation cycles with liquid production
FR2686405A1 (en) * 1992-01-20 1993-07-23 Air Liquide Air separation method and installation, and application of such an installation
JP2001133143A (en) * 1999-11-04 2001-05-18 Toshiba Corp Air separating facility
US6286336B1 (en) * 2000-05-03 2001-09-11 Praxair Technology, Inc. Cryogenic air separation system for elevated pressure product
FR2819046A1 (en) * 2001-01-03 2002-07-05 Air Liquide Cryogenic distillation air separation plant uses compressor to compress nitrogen-rich flow with inlet temperature below that of heat exchanger

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0518491A1 (en) 1991-05-14 1992-12-16 Air Products And Chemicals, Inc. Elevated pressure air separation cycles with liquid production
FR2686405A1 (en) * 1992-01-20 1993-07-23 Air Liquide Air separation method and installation, and application of such an installation
JP2001133143A (en) * 1999-11-04 2001-05-18 Toshiba Corp Air separating facility
US6286336B1 (en) * 2000-05-03 2001-09-11 Praxair Technology, Inc. Cryogenic air separation system for elevated pressure product
FR2819046A1 (en) * 2001-01-03 2002-07-05 Air Liquide Cryogenic distillation air separation plant uses compressor to compress nitrogen-rich flow with inlet temperature below that of heat exchanger

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107166872A (en) * 2017-04-27 2017-09-15 杭州颐氧健康科技有限公司 Health care gas deep cooling auto-pressurizing device for making and its method
US20220090856A1 (en) * 2020-09-21 2022-03-24 L'air Liquide, Societe Anonyme Pour L'etude Et L?Exploitation Des Procedes Georges Claude Apparatus for the separation of air by cryogenic distillation comprising three columns, including two concentric columns
CN115092891A (en) * 2022-05-16 2022-09-23 西安交通大学 Oxygen generator suitable for plateau environment and method
CN115092891B (en) * 2022-05-16 2023-08-15 西安交通大学 Oxygenerator and method suitable for plateau environment

Similar Documents

Publication Publication Date Title
US10746461B2 (en) Cryogenic air separation method for producing oxygen at high pressures
JP4733124B2 (en) Cryogenic air separation method for producing pressurized gas products
US6276171B1 (en) Integrated apparatus for generating power and/or oxygen enriched fluid, process for the operation thereof
EP2713128A1 (en) Process for the separation of air by cryogenic distillation
JP3161696B2 (en) Air separation method integrating combustion turbine
JP2758355B2 (en) Cryogenic air separation method for producing oxygen and pressurized nitrogen
US4962646A (en) Air separation
EP1767884A1 (en) Process and apparatus for the separation of air by cryogenic distillation
CN102652247B (en) Process and unit for the separation of air by cryogenic distillation
CN110678710B (en) Method and apparatus for separating air by cryogenic distillation
US5513497A (en) Separation of fluid mixtures in multiple distillation columns
US5839296A (en) High pressure, improved efficiency cryogenic rectification system for low purity oxygen production
US6718794B2 (en) Method and apparatus for generating energy
EP2741036A1 (en) Process and apparatus for the separation of air by cryogenic distillation
JP2000310481A (en) Method and device for separating cryogenic air
JPH11325717A (en) Separation of air
WO2011084285A2 (en) Process and apparatus for the separation of air by cryogenic distillation
US20080264101A1 (en) Process and Apparatus for Nitrogen Production
EP2662654A1 (en) Process and apparatus for the separation of air by cryogenic distillation
JPH1172286A (en) Method and plant for separating air by low temperature distillation
US20210348839A1 (en) System and method for cryogenic air separation using a booster loaded liquid turbine for expansion of a liquid air stream
JP2024063690A (en) Operation method of nitrogen production device
Smith et al. Air separation unit integration for alternative fuel projects

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

17P Request for examination filed

Effective date: 20121206

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

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

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20141212