WO2019180374A1 - Method and appliance for separating a synthesis gas by cryogenic distillation - Google Patents

Method and appliance for separating a synthesis gas by cryogenic distillation Download PDF

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Publication number
WO2019180374A1
WO2019180374A1 PCT/FR2019/050624 FR2019050624W WO2019180374A1 WO 2019180374 A1 WO2019180374 A1 WO 2019180374A1 FR 2019050624 W FR2019050624 W FR 2019050624W WO 2019180374 A1 WO2019180374 A1 WO 2019180374A1
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WO
WIPO (PCT)
Prior art keywords
column
gas
liquid
withdrawn
carbon monoxide
Prior art date
Application number
PCT/FR2019/050624
Other languages
French (fr)
Inventor
Bertrand DEMOLLIENS
Original Assignee
L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation 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
Priority claimed from FR1852439A external-priority patent/FR3079288B1/en
Application filed by L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude filed Critical L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude
Priority to KR1020207028610A priority Critical patent/KR20200135805A/en
Priority to US16/982,846 priority patent/US20210055047A1/en
Priority to SG11202008918SA priority patent/SG11202008918SA/en
Priority to EP19716467.6A priority patent/EP3769022A1/en
Priority to CN201980020597.7A priority patent/CN111886465B/en
Priority to PCT/FR2019/050624 priority patent/WO2019180374A1/en
Publication of WO2019180374A1 publication Critical patent/WO2019180374A1/en

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
    • F25J3/0204—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 characterised by the feed stream
    • F25J3/0223—H2/CO mixtures, i.e. synthesis gas; Water gas or shifted synthesis gas
    • 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
    • F25J3/0228—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 characterised by the separated product stream
    • F25J3/0233—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 characterised by the separated product stream separation of CnHm with 1 carbon atom or more
    • 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
    • F25J3/0228—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 characterised by the separated product stream
    • F25J3/0252—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 characterised by the separated product stream separation of hydrogen
    • 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
    • F25J3/0228—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 characterised by the separated product stream
    • F25J3/0257—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 characterised by the separated product stream separation 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
    • F25J3/0228—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 characterised by the separated product stream
    • F25J3/0261—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 characterised by the separated product stream separation of carbon monoxide
    • 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
    • F25J2200/40—Features relating to the provision of boil-up in the bottom of a 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
    • F25J2200/50—Processes or apparatus using separation by rectification using multiple (re-)boiler-condensers at different heights of the 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
    • F25J2200/70—Refluxing the column with a condensed part of the feed stream, i.e. fractionator top is stripped or self-rectified
    • 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
    • F25J2200/74—Refluxing the column with at least a part of the partially condensed overhead gas
    • 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
    • F25J2200/76—Refluxing the column with condensed overhead gas being cycled in a quasi-closed loop refrigeration cycle
    • 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
    • F25J2205/04—Processes or apparatus using other separation and/or other processing means using simple phase separation in a vessel or drum in the feed line, i.e. upstream of the fractionation step
    • 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
    • F25J2205/24—Processes or apparatus using other separation and/or other processing means using regenerators, cold accumulators or reversible heat exchangers
    • 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
    • F25J2205/30—Processes or apparatus using other separation and/or other processing means using a washing, e.g. "scrubbing" or bubble column for purification purposes
    • 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
    • F25J2235/60—Processes or apparatus involving steps for increasing the pressure or for conveying of liquid process streams the fluid being (a mixture of) hydrocarbons
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2270/00—Refrigeration techniques used
    • F25J2270/02—Internal refrigeration with liquid vaporising loop
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2270/00—Refrigeration techniques used
    • F25J2270/04—Internal refrigeration with work-producing gas expansion loop
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2270/00—Refrigeration techniques used
    • F25J2270/24—Quasi-closed internal or closed external carbon monoxide refrigeration cycle
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2270/00—Refrigeration techniques used
    • F25J2270/88—Quasi-closed internal refrigeration or heat pump cycle, if not otherwise provided
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2270/00—Refrigeration techniques used
    • F25J2270/90—External refrigeration, e.g. conventional closed-loop mechanical refrigeration unit using Freon or NH3, unspecified external refrigeration
    • F25J2270/902—Details about the refrigeration cycle used, e.g. composition of refrigerant, arrangement of compressors or cascade, make up sources, use of reflux exchangers etc.

Definitions

  • the present invention relates to a method and an apparatus for separating a synthesis gas by cryogenic distillation.
  • the synthesis gas contains as major components hydrogen, methane and carbon monoxide. It may also contain nitrogen.
  • the first column carries out a methane wash in order to recover a fraction rich in CO and methane in the tank and at the top a fraction rich in hydrogen.
  • the second column or column of exhaustion (called flash column in English) is used to evacuate the few percent of hydrogen contained in the liquid fraction of the first column.
  • the present invention improves performance by using existing wash column equipment with intermediate gas cooling. Among the objects of the invention, it is desired:
  • the idea of the invention is to cool and at least partially condense a gas withdrawn into an upper part of the exhaust column in an exchanger where at least one intermediate gas is cooled in the methane washing column and returning at least a portion of the at least partially condensed gas to the top of the exhaust column.
  • the depletion column includes an upper portion and a lower portion, below the upper portion.
  • the CO efficiency of about 0.5 to 1% can be increased compared to the case with the minaret.
  • this overhead gas of the counter-current exhaustion column with another fluid of the cold box, for example liquid CO.
  • a liquid CO capacity is installed at the top of the methane scrubbing column in order to operate at the temperature above the temperature. lowest possible. It would therefore be sufficient to add the gas from the exhaustion column into a heat exchanger for heating the liquid CO from the capacity in order to increase the CO recovery efficiency.
  • This overhead gas from the exhaustion column represents only a fraction of the synthesis gas flow (2-3%), whereas the gas treated in normal time represents approximately the total flow of hydrogen, ie 70% of the flow rate. .
  • the addition of this overhead column fluid in the heat exchanger is therefore marginal in terms of investment and improves performance.
  • a process for separating a synthesis gas comprising hydrogen, carbon monoxide and methane and optionally nitrogen by cryogenic distillation in which: i) the gas of synthesis is purified and cooled to a cryogenic temperature,
  • the cooled synthesis gas is separated by a first means to produce a hydrogen-depleted liquid
  • the separation carried out by the first means is constituted by a washing step in a washing column with at least a part of the methane-enriched liquid withdrawn from a carbon monoxide and methane separation column having an overhead condenser, the condenser being cooled by a carbon monoxide cycle, and
  • the hydrogen-depleted liquid is introduced into the upper part of a depletion column which also comprises a lower part, iv) a hydrogen-enriched gas is withdrawn at the top of the depletion column,
  • a liquid is withdrawn in the tank from the exhaustion column and sent to the separation column, a carbon monoxide enriched and methanol-depleted gas is withdrawn at the top of the separation column, a liquid depleted in carbon monoxide and enriched in methane is withdrawn in the bottom of the separation column and the carbon monoxide enriched gas is heated by heat exchange with the synthesis gas of step i) to form a product, vi) a gas withdrawn into the upper part of the depletion column is at least partially condensed and returned at least in part to the upper part of the depletion column characterized in that the gas withdrawn in the upper part of the column at least partially condensed in a heat exchanger which also serves to cool at least one gas withdrawn from the washing column, the heat exchanger also serving to heat a refrigerant.
  • the gas withdrawn at the top of the depletion column condenses against at least a portion of the carbon monoxide cycle liquid.
  • the synthesis gas comprises nitrogen and the liquid withdrawn from the depletion column or a fluid derived from this liquid is separated in a denitrogenation column, the liquid of which serves to at least partially condense the overhead gas of the column exhaustion.
  • the gas withdrawn into the upper part of the depletion column is at least partially condensed by heat exchange with a carbon monoxide enriched liquid withdrawn from the separating column which heats up and optionally vaporises at least partially.
  • the liquid enriched in carbon monoxide is withdrawn from a distillation section of the separation column or from a capacity forming the head of the separation column.
  • the gas withdrawn from the top of the depletion column is a top gas of the exhaust column withdrawn at a level above any means of heat transfer and mass of the exhaust column.
  • the gas withdrawn from the upper part of the depletion column is withdrawn at least one theoretical plate below the head of the depletion column, a part of the methane-enriched liquid withdrawn from the separation column being sent to a level of the column of exhaustion above the level of withdrawal of the gas.
  • the separation carried out by the first means does not include a washing step with a liquid enriched in methane.
  • the process is kept cold by a cycle using the carbon monoxide enriched gas from the separation column.
  • the hydrogen-depleted liquid contains between 1 and 3 mol% of hydrogen.
  • the refrigerant is enriched in carbon monoxide
  • the refrigerant is a liquid enriched in carbon monoxide, possibly from the separation column, which vaporizes in the second heat exchanger
  • the second heat exchanger is heated only by means of the refrigerant.
  • an apparatus for separating a synthesis gas comprising hydrogen, carbon monoxide, methane and optionally nitrogen by cryogenic distillation comprising a heat exchanger, a first separation means which is a methane washing column, a depletion column and optionally a carbon monoxide and methane separation column, means for purifying the synthesis gas, means for sending the purified gas to cooling in the heat exchanger to a cryogenic temperature, means for sending the cooled synthesis gas to the first means for producing a hydrogen-depleted liquid, means for introducing the hydrogen-depleted liquid into the upper part of the column of depletion which also comprises a lower part, means for withdrawing a hydrogen-enriched gas at the top of the depletion column, means for for withdrawing a liquid in the bottom of the exhaust column, a second heat exchanger, means for sending a gas withdrawn into the upper part of the exhaust column and means for sending at least a portion of the gas at least partially condensed in the second heat exchanger to
  • the apparatus may also include:
  • a denitrogenization column for separating the liquid withdrawn from the depletion column or a fluid derived from this liquid.
  • means for withdrawing the carbon monoxide enriched liquid is from a distillation section of the separation column or from a capacity forming the top of the separation column.
  • the cold holding means of the process comprise a cycle using the carbon monoxide enriched gas from the separation column.
  • the second heat exchanger is an indirect heat exchanger.
  • Figure 1 shows a process using a phase separator 9, a methane scrubbing column 15, a depletion column and a carbon monoxide and methane separation column 45, for example containing structured packings for the columns. and capable of operating at cryogenic temperatures.
  • the synthesis gas 1 containing carbon monoxide, methane and carbon monoxide is purified with water and / or carbon dioxide in the purification unit 3 before arriving at the heat exchanger 7 where it cools to a cryogenic temperature and partially condenses.
  • the two phases are separated in a phase separator 9 to form a hydrogen-enriched gas 11 and a hydrogen-depleted liquid 13.
  • the gas 11 is sent to the bottom of the methane scrubber column which produces a gas enriched with hydrogen that heats up in the exchanger. Part of this gas 19 serves to regenerate the purification unit 3.
  • At least one intermediate gas 21 A, 21 B, 21 C withdrawn from the column 15 is cooled in a heat exchanger 23 by indirect heat exchange with a process fluid, here the liquid 51.
  • the tank liquid 17 of the column 15 joins the liquid 13 of the separator 9 and the mixture 91 containing between 1 and 3 mol% of hydrogen is sent to the top of a depletion column 25.
  • a top gas 27 of the The exhaust column at least partially condenses in the heat exchanger 23. At least a portion 31 of the at least partially condensed gas is returned to the top of the depletion column 25 to provide reflux liquid.
  • the remainder 29 can be heated in the heat exchanger 7 against the synthesis gas 5.
  • the refrigerant gas 27 leaving to be cooled in the heat exchanger 23 undergoes at least partial condensation.
  • partial condensation liquid and gas are created. It is possible that a portion of the liquid created passes through another pipe 31 or then falls through the pipe 27 from which the refrigerant gas to be cooled, to join the column 25. In this second case, the pipe 31 is not necessary .
  • a liquid 33 taken in the bottom of the depletion column 25 cools in the exchange 7 and is sent to the separation column 45.
  • Another part of the same liquid 35 vaporizes in a bottom reboiler 37 and is returned to the tank from the column of exhaustion.
  • the separation column comprises a plurality of distillation separation sections and optionally a capacity 99. It has a bottom reboiler 73 which serves to heat the bottom liquid 75, the formed gas being returned to the vessel.
  • the tank liquid 77 enriched with methane is divided in two. Part 83 vaporizes in exchanger 7 to form fuel.
  • the remainder 85 is pressurized by a pump 87 and is sent to the top of the washing column 15.
  • the overhead gas from the carbon monoxide enriched column 43 is fed to a product compressor 57 which produces a gas enriched with carbon monoxide 57.
  • Part of the carbon monoxide enriched gas 61 is cooled and split in half.
  • Part 65 is expanded in a turbine 67 to provide cold.
  • the expanded gas 89 is returned to the inlet of the compressor 57.
  • the remaining gas 69 continues to cool in the exchanger 7 and is used to heat the reboilers 73 and 37 (flow rates 93 and 73).
  • the gas used for the reboiling is thus partially condensed and feeds as the flow 97 the capacity 99 at the top of the separation column 45.
  • the gas 41 of the capacity 99 feeds the compressor 57.
  • the liquid 47 of the capacity 99 is sent to a phase separator 49, the liquid 51 of the separator serves as a refrigerant in the heat exchanger 23 for cooling the intermediate gases 21 A, 21 B, 21 C and the overhead gas 27 of the depletion column.
  • the liquid 51 is thus vaporized and returned to the phase separator 49 whose gas 53 supplies the compressor 57.
  • a liquid withdrawn from the separation section of the separation column can replace the liquid 47 or other liquid of the process.
  • the exhaustion column comprising a methane washing section, a part of the liquid 85 pressurized by the pump 87 being sent to the top of the depletion column 25 and another part being sent as for Figure 1 at the top of the washing column 15.
  • the gas 27 withdrawn from the depletion column 25 is taken at least one theoretical plate below the head of the column.
  • the at least partially condensed gas in the exchanger 23 returns to the exhaust column adjacent to the draw-off point and the rising gas in the upper part of the depletion column (washing section 25A) becomes more enriched in hydrogen, to reduce the number of theoretical plates required.
  • the invention also applies to the case where the process does not use a methane scrubbing column.
  • the first separation is carried out simply by partial condensation in the separator 9.
  • the gas 11 is heated and the hydrogen-depleted liquid 13 is sent to the depletion column 25.
  • This may include a methane wash section, as for Figure 2, or not as needed.
  • methane wash section 25A is present and thus the gas 27 drawn off in the exhaustion column is taken at an intermediate level as in FIG. 2.
  • the heat exchanger 23 is simplified and allows a heat exchange between two single fluids, the gas to be cooled 27 and the liquid to be heated 51.
  • the gas 27 is taken at the top of the column 25.

Abstract

The invention relates to a method for separating a synthesis gas comprising hydrogen and carbon monoxide by cryogenic distillation, according to which the synthesis gas (1, 5) is cleaned and cooled to a cryogenic temperature, the cooled synthesis gas is separated by a first means (15) in order to produce a hydrogen-depleted liquid (33), the hydrogen-depleted liquid is introduced into the upper part of a stripping column (25) and a hydrogen-enriched gas (27) is drawn off at the head of the stripping column, at least partially condensed and sent back to the upper part of the stripping column.

Description

PROCEDE ET APPAREIL DE SEPARATION D’UN GAZ DE SYNTHESE METHOD AND APPARATUS FOR SEPARATING A SYNTHESIS GAS
PAR DISTILLATION CRYOGENIQUE BY CRYOGENIC DISTILLATION
La présente invention est relative à un procédé et à un appareil de séparation d’un gaz de synthèse par distillation cryogénique. The present invention relates to a method and an apparatus for separating a synthesis gas by cryogenic distillation.
Le gaz de synthèse contient comme composants majeurs l’hydrogène, le méthane et le monoxyde de carbone. Il peut également contenir de l’azote.  The synthesis gas contains as major components hydrogen, methane and carbon monoxide. It may also contain nitrogen.
Il est connu d’utiliser des procédés de type lavage au méthane, décrits dans EP 0 465 366, pour séparer un gaz de synthèse en ses différents constituants. Ce procédé repose notamment sur l’utilisation d’une fraction d’un fluide riche en méthane récupéré en cuve de colonne CO/CH4 comme fluide de lavage, l’autre fraction de ce fluide étant alors récupérée sous forme de purge de méthane.  It is known to use methods of the methane washing type, described in EP 0 465 366, for separating a synthesis gas into its various constituents. This process is based in particular on the use of a fraction of a methane-rich fluid recovered in a CO / CH4 column vessel as a washing fluid, the other fraction of this fluid then being recovered in the form of a methane purge.
La première colonne réalise un lavage au méthane afin de récupérer en cuve une fraction riche en CO et en méthane et en tête une fraction riche en hydrogène.  The first column carries out a methane wash in order to recover a fraction rich in CO and methane in the tank and at the top a fraction rich in hydrogen.
La deuxième colonne ou colonne d’épuisement (dite flash column en anglais) sert à évacuer les quelques pourcents d’hydrogène contenus dans la fraction liquide de la première colonne.  The second column or column of exhaustion (called flash column in English) is used to evacuate the few percent of hydrogen contained in the liquid fraction of the first column.
II est également connu d’après le brevet FR 2 807 505 A1 ou FR 2 807 504 It is also known from the patent FR 2 807 505 A1 or FR 2 807 504
A1 de procéder à des refroidissements successifs du gaz dans la colonne de lavage au méthane. A1 to successively cool the gas in the methane wash column.
En effet, le lavage étant exothermique et plus efficace à basse température, se rapprocher de la température la plus froide possible permet d’améliorer le rendement du lavage au méthane de la première colonne.  Indeed, the washing being exothermic and more effective at low temperature, approaching the coldest possible temperature improves the performance of the methane washing of the first column.
Des procédés selon le préambule de la revendication 1 sont connus de WO2013/178901 et EP317851. Selon ces procédés de l’art antérieur, le gaz de tête de la colonne d’épuisement est refroidi au moyen d’un échangeur dédié présent dans la colonne ou d’une colonne auxiliaire associée à la colonne de lavage au méthane.  Methods according to the preamble of claim 1 are known from WO2013 / 178901 and EP317851. According to these methods of the prior art, the overhead column of the exhaustion column is cooled by means of a dedicated exchanger present in the column or of an auxiliary column associated with the methane washing column.
La présente invention permet d’améliorer les performances, en utilisant un matériel existant de colonne de lavage avec refroidissement de gaz intermédiaire. Parmi les objets de l’invention, il est souhaité : The present invention improves performance by using existing wash column equipment with intermediate gas cooling. Among the objects of the invention, it is desired:
• Soit améliorer le rendement de récupération de CO dans une unité de séparation de gaz de synthèse,  • Either improve the recovery efficiency of CO in a synthesis gas separation unit,
• Soit optimiser l’investissement à iso-rendement de CO par une disposition particulière de la colonne d’épuisement.  • Either optimize the CO iso-efficiency investment by a particular disposition of the depletion column.
L’idée de l’invention est de refroidir et de condenser au moins partiellement un gaz soutiré en une partie supérieure de la colonne d’épuisement dans un échangeur où se refroidit au moins un gaz intermédiaire de la colonne de lavage au méthane et d’en renvoyer au moins une partie du gaz au moins partiellement condensé vers la partie supérieure de colonne d’épuisement. La colonne d’épuisement comprend une partie supérieure et une partie inférieure, en dessous de la partie supérieure.  The idea of the invention is to cool and at least partially condense a gas withdrawn into an upper part of the exhaust column in an exchanger where at least one intermediate gas is cooled in the methane washing column and returning at least a portion of the at least partially condensed gas to the top of the exhaust column. The depletion column includes an upper portion and a lower portion, below the upper portion.
En refroidissant, ce gaz soutiré de la partie supérieure, se condense une portion importante de CO et de méthane. La fraction liquide retombera en reflux de tête de colonne d’épuisement et augmentera par là même le rendement de CO et de méthane. Cela permet de remplacer partiellement le minaret de EP 0 317 851 A2 et de récupérer du rendement pour un coût marginal (voir ci-après) By cooling, this gas withdrawn from the upper part, condenses a large portion of CO and methane. The liquid fraction will reflux back to the top of the exhaust column and thereby increase the yield of CO and methane. This makes it possible to partially replace the minaret of EP 0 317 851 A2 and to recover yield for a marginal cost (see below)
Cela permet également de faciliter l’opération. En général, lorsque la colonne d’épuisement est mal-réglée, une quantité non négligeable de CO part en tête de colonne. Ce refroidissement permet donc de faciliter l’opération de l’unité et de pouvoir compenser certaines pertes de rendement de CO en augmentant légèrement le débit du compresseur de cycle. This also makes the operation easier. In general, when the depletion column is badly adjusted, a significant amount of CO goes to the top of the column. This cooling thus makes it possible to facilitate the operation of the unit and to be able to compensate for certain losses of CO efficiency by slightly increasing the flow rate of the cycle compressor.
Différents fluides peuvent être utilisés, selon les colonnes présentes, pour condenser le gaz de tête de la colonne d’épuisement.  Different fluids can be used, depending on the columns present, to condense the overhead gas of the depletion column.
Ensuite, dans le cas où l’on combine cette invention avec un minaret de colonne d’épuisement tel que décrit dans le EP 0 317 851- A2, le gaz de tête montant dans le minaret entrera dans la section de lavage à une température plus basse. Le lavage au méthane du minaret sera donc d’autant plus efficace.  Then, in the case where this invention is combined with a depletion column minaret as described in EP 0 317 851-A2, the rising head gas in the minaret will enter the wash section at a higher temperature. low. The methane wash of the minaret will therefore be all the more effective.
On pourra augmenter le rendement de CO d’environ 0,5 à 1 % par rapport au cas avec le minaret.  The CO efficiency of about 0.5 to 1% can be increased compared to the case with the minaret.
On pourra par exemple refroidir ce gaz de tête de la colonne d’épuisement à contre-courant d’un autre fluide de la boîte froide comme par exemple du CO liquide. Il est intéressant de noter que dans le cadre de lavage au méthane, suivant le dispositif décrit dans le FR 2 807 505- A1 , une capacité de CO liquide est installée en tête de colonne de lavage au méthane afin d’opérer à la température la plus basse possible. Il suffirait donc d’ajouter le gaz provenant de la colonne d’épuisement dans un échangeur servant à réchauffer le CO liquide provenant de la capacité afin d’augmenter le rendement de récupération de CO. Ce gaz de tête de la colonne d’épuisement ne représente qu’une fraction du débit de gaz de synthèse (2-3%), tandis que le gaz traité en temps normal représente environ tout le débit d’hydrogène soit 70% du débit. L’ajout de ce fluide de tête de colonne d’épuisement dans l’échangeur est donc marginal en termes d’investissement et permet d’améliorer le rendement. For example, it is possible to cool this overhead gas of the counter-current exhaustion column with another fluid of the cold box, for example liquid CO. It is interesting to note that in the context of methane scrubbing, according to the device described in FR 2 807 505-A1, a liquid CO capacity is installed at the top of the methane scrubbing column in order to operate at the temperature above the temperature. lowest possible. It would therefore be sufficient to add the gas from the exhaustion column into a heat exchanger for heating the liquid CO from the capacity in order to increase the CO recovery efficiency. This overhead gas from the exhaustion column represents only a fraction of the synthesis gas flow (2-3%), whereas the gas treated in normal time represents approximately the total flow of hydrogen, ie 70% of the flow rate. . The addition of this overhead column fluid in the heat exchanger is therefore marginal in terms of investment and improves performance.
Selon un objet de l’invention, il est prévu un procédé de séparation d’un gaz de synthèse comprenant de l’hydrogène, du monoxyde de carbone et du méthane et éventuellement d’azote par distillation cryogénique dans lequel : i) le gaz de synthèse est épuré et refroidi jusqu’à une température cryogénique,  According to one object of the invention, there is provided a process for separating a synthesis gas comprising hydrogen, carbon monoxide and methane and optionally nitrogen by cryogenic distillation in which: i) the gas of synthesis is purified and cooled to a cryogenic temperature,
ii) le gaz de synthèse refroidi est séparé par un premier moyen pour produire un liquide appauvri en hydrogène , la séparation effectuée par le premier moyen est constituée par une étape de lavage dans une colonne de lavage avec au moins une partie du liquide enrichi en méthane soutiré d’une colonne de séparation de monoxyde de carbone et de méthane ayant un condenseur de tête, le condenseur étant refroidi par un cycle de monoxyde de carbone, et  ii) the cooled synthesis gas is separated by a first means to produce a hydrogen-depleted liquid, the separation carried out by the first means is constituted by a washing step in a washing column with at least a part of the methane-enriched liquid withdrawn from a carbon monoxide and methane separation column having an overhead condenser, the condenser being cooled by a carbon monoxide cycle, and
iii) le liquide appauvri en hydrogène est introduit dans la partie supérieure d’une colonne d’épuisement qui comprend également une partie inférieure, iv) un gaz enrichi en hydrogène est soutiré en tête de la colonne d’épuisement,  iii) the hydrogen-depleted liquid is introduced into the upper part of a depletion column which also comprises a lower part, iv) a hydrogen-enriched gas is withdrawn at the top of the depletion column,
v) un liquide est soutiré en cuve de la colonne d’épuisement et envoyé à la colonne de séparation, un gaz enrichi en monoxyde de carbone et appauvri en méthane est soutiré en tête de la colonne de séparation, un liquide appauvri en monoxyde de carbone et enrichi en méthane est soutiré en cuve de la colonne de séparation et le gaz enrichi en monoxyde de carbone est réchauffé par échange de chaleur avec le gaz de synthèse de l’étape i) pour former un produit, vi) un gaz soutiré dans la partie supérieure de la colonne d’épuisement est au moins partiellement condensé et renvoyé au moins en partie à la partie supérieure de la colonne d’épuisement caractérisé en ce que le gaz soutiré dans la partie supérieure de la colonne d’épuisement est au moins partiellement condensé dans un échangeur de chaleur qui sert également à refroidir au moins un gaz soutiré de la colonne de lavage, l’échangeur de chaleur servant également à réchauffer un fluide frigorigène. v) a liquid is withdrawn in the tank from the exhaustion column and sent to the separation column, a carbon monoxide enriched and methanol-depleted gas is withdrawn at the top of the separation column, a liquid depleted in carbon monoxide and enriched in methane is withdrawn in the bottom of the separation column and the carbon monoxide enriched gas is heated by heat exchange with the synthesis gas of step i) to form a product, vi) a gas withdrawn into the upper part of the depletion column is at least partially condensed and returned at least in part to the upper part of the depletion column characterized in that the gas withdrawn in the upper part of the column at least partially condensed in a heat exchanger which also serves to cool at least one gas withdrawn from the washing column, the heat exchanger also serving to heat a refrigerant.
Selon d’autres aspects facultatifs :  According to other optional aspects:
le gaz soutiré en partie supérieur de la colonne d’épuisement se condense contre au moins une partie du liquide de cycle de monoxyde de carbone.  the gas withdrawn at the top of the depletion column condenses against at least a portion of the carbon monoxide cycle liquid.
le gaz de synthèse comprend de l’azote et le liquide soutiré de la colonne d’épuisement ou un fluide dérivé de ce liquide est séparé dans une colonne de déazotation, dont le liquide sert à condenser au moins partiellement le gaz de tête de la colonne d’épuisement.  the synthesis gas comprises nitrogen and the liquid withdrawn from the depletion column or a fluid derived from this liquid is separated in a denitrogenation column, the liquid of which serves to at least partially condense the overhead gas of the column exhaustion.
le gaz soutiré dans la partie supérieure de la colonne d’épuisement est au moins partiellement condensé par échange de chaleur avec un liquide enrichi en monoxyde de carbone soutiré de la colonne de séparation qui se réchauffe et éventuellement se vaporise au moins partiellement.  the gas withdrawn into the upper part of the depletion column is at least partially condensed by heat exchange with a carbon monoxide enriched liquid withdrawn from the separating column which heats up and optionally vaporises at least partially.
- le liquide enrichi en monoxyde de carbone est soutiré d’une section de distillation de la colonne de séparation ou d’une capacité formant la tête de la colonne de séparation.  the liquid enriched in carbon monoxide is withdrawn from a distillation section of the separation column or from a capacity forming the head of the separation column.
le gaz soutiré de la partie supérieure de la colonne d’épuisement est un gaz de tête de la colonne d’épuisement soutiré à un niveau au-dessus de tout moyen de transfert de chaleur et de masse de la colonne d’épuisement.  the gas withdrawn from the top of the depletion column is a top gas of the exhaust column withdrawn at a level above any means of heat transfer and mass of the exhaust column.
le gaz soutiré de partie supérieure de la colonne d’épuisement est soutiré au moins un plateau théorique en dessous de la tête de la colonne d’épuisement, une partie du liquide enrichi en méthane soutiré de la colonne de séparation étant envoyée à un niveau de la colonne d’épuisement au-dessus du niveau de soutirage du gaz.  the gas withdrawn from the upper part of the depletion column is withdrawn at least one theoretical plate below the head of the depletion column, a part of the methane-enriched liquid withdrawn from the separation column being sent to a level of the column of exhaustion above the level of withdrawal of the gas.
la séparation effectuée par le premier moyen ne comprend pas d’étape de lavage avec un liquide enrichi en méthane.  the separation carried out by the first means does not include a washing step with a liquid enriched in methane.
le procédé est tenu en froid par un cycle utilisant le gaz enrichi en monoxyde de carbone provenant de la colonne de séparation. le liquide appauvri en hydrogène contient entre 1 et 3% mol d’hydrogène. the process is kept cold by a cycle using the carbon monoxide enriched gas from the separation column. the hydrogen-depleted liquid contains between 1 and 3 mol% of hydrogen.
le fluide frigorigène est enrichi en monoxyde de carbone  the refrigerant is enriched in carbon monoxide
le fluide frigorigène est un liquide enrichi en monoxyde de carbone, éventuellement provenant de la colonne de séparation, qui se vaporise dans le deuxième échangeur de chaleur  the refrigerant is a liquid enriched in carbon monoxide, possibly from the separation column, which vaporizes in the second heat exchanger
le deuxième échangeur de chaleur est réchauffé uniquement au moyen du fluide frigorigène.  the second heat exchanger is heated only by means of the refrigerant.
Selon un autre objet de l’invention, il est prévu un appareil de séparation d’un gaz de synthèse comprenant de l’hydrogène, du monoxyde de carbone, du méthane et éventuellement de l’azote par distillation cryogénique comprenant un échangeur de chaleur, un premier moyen de séparation qui est une colonne de lavage au méthane, une colonne d’épuisement et éventuellement une colonne de séparation de monoxyde de carbone et de méthane, des moyens pour épurer le gaz de synthèse, des moyens pour envoyer le gaz épuré se refroidir dans l’échangeur de chaleur jusqu’à une température cryogénique, des moyens pour envoyer le gaz de synthèse refroidi au premier moyen pour produire un liquide appauvri en hydrogène , des moyens pour introduire le liquide appauvri en hydrogène dans la partie supérieure de la colonne d’épuisement qui comprend également une partie inférieure, des moyens pour soutirer un gaz enrichi en hydrogène en tête de la colonne d’épuisement, des moyens pour soutirer un liquide en cuve de la colonne d’épuisement, un deuxième échangeur de chaleur, des moyens pour y envoyer un gaz soutiré dans la partie supérieure de la colonne d’épuisement et des moyens pour envoyer au moins une partie du gaz au moins partiellement condensé dans le deuxième échangeur de chaleur vers la partie supérieure de la colonne d’épuisement, des moyens pour envoyer le liquide de cuve de colonne d’épuisement à la colonne de séparation de monoxyde de carbone et de méthane, des moyens pour soutirer un gaz enrichi en monoxyde de carbone et appauvri en méthane en tête de la colonne de séparation, des moyens pour soutirer un liquide appauvri en monoxyde de carbone et enrichi en méthane en cuve de la colonne de séparation et des moyens pour envoyer le gaz enrichi en monoxyde de carbone se réchauffer dans l’échangeur de chaleur par échange de chaleur avec le gaz de synthèse pour former un produit caractérisé en ce qu’il comprend des moyens pour envoyer au moins un gaz soutiré de la colonne de lavage se refroidir dans le deuxième échangeur de chaleur et des moyens pour envoyer au moins un fluide frigorigène se réchauffer dans le deuxième échangeur de chaleur. According to another object of the invention, there is provided an apparatus for separating a synthesis gas comprising hydrogen, carbon monoxide, methane and optionally nitrogen by cryogenic distillation comprising a heat exchanger, a first separation means which is a methane washing column, a depletion column and optionally a carbon monoxide and methane separation column, means for purifying the synthesis gas, means for sending the purified gas to cooling in the heat exchanger to a cryogenic temperature, means for sending the cooled synthesis gas to the first means for producing a hydrogen-depleted liquid, means for introducing the hydrogen-depleted liquid into the upper part of the column of depletion which also comprises a lower part, means for withdrawing a hydrogen-enriched gas at the top of the depletion column, means for for withdrawing a liquid in the bottom of the exhaust column, a second heat exchanger, means for sending a gas withdrawn into the upper part of the exhaust column and means for sending at least a portion of the gas at least partially condensed in the second heat exchanger to the top of the depletion column, means for sending the exhaustion column bottom liquid to the carbon monoxide and methane separation column, means for withdrawing a gas enriched in carbon monoxide and depleted of methane at the top of the separation column, means for withdrawing a liquid depleted of carbon monoxide and enriched in methane tank of the separation column and means for sending the gas enriched in monoxide of carbon heat up in the heat exchanger by heat exchange with the synthesis gas to form a product characterized in that it comprises means for send at least one gas withdrawn from the washing column to cool in the second heat exchanger and means for sending at least one refrigerant to heat in the second heat exchanger.
L’appareil peut également comprendre :  The apparatus may also include:
- des moyens pour soutirer le gaz en partie supérieure de la colonne d’épuisement et pour l’envoyer se condenser contre au moins une partie du liquide de cycle de monoxyde de carbone.  means for withdrawing the gas in the upper part of the depletion column and for sending it to condense against at least a part of the carbon monoxide cycle liquid.
si le gaz de synthèse comprend de l’azote, une colonne de déazotation pour séparer le liquide soutiré de la colonne d’épuisement ou un fluide dérivé de ce liquide.  if the synthesis gas comprises nitrogen, a denitrogenization column for separating the liquid withdrawn from the depletion column or a fluid derived from this liquid.
des moyens pour envoyer le liquide soutiré de la colonne d’épuisement pour servir à condenser au moins partiellement le gaz de tête de la colonne d’épuisement.  means for sending the liquid withdrawn from the depletion column to at least partially condense the overhead gas of the depletion column.
des moyens pour permettre un échange de chaleur entre le gaz soutiré dans la partie supérieure de la colonne d’épuisement et un liquide enrichi en monoxyde de carbone soutiré de la colonne de séparation qui se réchauffe et éventuellement se vaporise au moins partiellement.  means for permitting heat exchange between the gas withdrawn in the upper part of the depletion column and a carbon monoxide enriched liquid withdrawn from the separating column which heats up and optionally vaporises at least partially.
des moyens pour soutirer le liquide enrichi en monoxyde de carbone est d’une section de distillation de la colonne de séparation ou d’une capacité formant la tête de la colonne de séparation.  means for withdrawing the carbon monoxide enriched liquid is from a distillation section of the separation column or from a capacity forming the top of the separation column.
des moyens pour soutirer le gaz soutiré de la partie supérieure de la colonne d’épuisement comme gaz de tête de la colonne d’épuisement soutiré à un niveau au-dessus de tout moyen de transfert de chaleur et de masse de la colonne d’épuisement.  means for withdrawing gas withdrawn from the top of the depletion column as overhead gas of the exhaust column withdrawn at a level above any heat transfer and mass means of the exhaust column .
- des moyens pour soutirer le gaz soutiré de partie supérieure de la colonne d’épuisement au moins un plateau théorique en dessous de la tête de la colonne d’épuisement.  - Means for withdrawing the gas withdrawn from the upper part of the depletion column at least one theoretical plate below the head of the depletion column.
des moyens pour envoyer une partie du liquide enrichi en méthane soutiré de la colonne de séparation à un niveau de la colonne d’épuisement au- dessus du niveau de soutirage du gaz.  means for sending a portion of the methane-enriched liquid withdrawn from the separation column to a level of the depletion column above the gas withdrawal level.
les moyens de maintien en froid du procédé comprennent un cycle utilisant le gaz enrichi en monoxyde de carbone provenant de la colonne de séparation. le deuxième échangeur de chaleur est un échangeur de chaleur indirecte. the cold holding means of the process comprise a cycle using the carbon monoxide enriched gas from the separation column. the second heat exchanger is an indirect heat exchanger.
L’invention sera décrite de manière plus détaillée en se référant aux figures, chacune desquelles représente figurativement un procédé selon l’invention.  The invention will be described in more detail with reference to the figures, each of which represents figuratively a method according to the invention.
La Figure 1 montre un procédé utilisant un séparateur de phase 9, une colonne de lavage au méthane 15, une colonne d’épuisement 25 et une colonne de séparation de monoxyde de carbone et de méthane 45, contenant par exemple des garnissages structurés pour les colonnes et capables de fonctionner à des températures cryogéniques.  Figure 1 shows a process using a phase separator 9, a methane scrubbing column 15, a depletion column and a carbon monoxide and methane separation column 45, for example containing structured packings for the columns. and capable of operating at cryogenic temperatures.
Le gaz de synthèse 1 contenant du monoxyde de carbone, du méthane et du monoxyde de carbone est épuré en eau et/ou en dioxyde de carbone dans l’unité d’épuration 3 avant d’arriver à l’échangeur de chaleur 7 où il se refroidit jusqu’à une température cryogénique et se condense partiellement.  The synthesis gas 1 containing carbon monoxide, methane and carbon monoxide is purified with water and / or carbon dioxide in the purification unit 3 before arriving at the heat exchanger 7 where it cools to a cryogenic temperature and partially condenses.
Les deux phases sont séparées dans un séparateur de phases 9, pour former un gaz 11 enrichi en hydrogène et un liquide appauvri en hydrogène 13. Le gaz 11 est envoyé en cuve de la colonne de lavage au méthane 15 qui produit un gaz 19 enrichi en hydrogène qui se réchauffe dans l’échangeur. Une partie de ce gaz 19 sert à régénérer l’unité d’épuration 3.  The two phases are separated in a phase separator 9 to form a hydrogen-enriched gas 11 and a hydrogen-depleted liquid 13. The gas 11 is sent to the bottom of the methane scrubber column which produces a gas enriched with hydrogen that heats up in the exchanger. Part of this gas 19 serves to regenerate the purification unit 3.
Au moins un gaz intermédiaire 21 A, 21 B, 21 C soutiré de la colonne 15 est refroidi dans un échangeur de chaleur 23 par échange de chaleur indirecte avec un fluide du procédé, ici le liquide 51.  At least one intermediate gas 21 A, 21 B, 21 C withdrawn from the column 15 is cooled in a heat exchanger 23 by indirect heat exchange with a process fluid, here the liquid 51.
Le liquide de cuve 17 de la colonne 15 rejoint le liquide 13 du séparateur 9 et le mélange 91 contenant entre 1 et 3% mol d’hydrogène est envoyé en tête d’une colonne d’épuisement 25. Un gaz de tête 27 de la colonne d’épuisement se condense au moins partiellement dans l’échangeur de chaleur 23. Une partie 31 au moins du gaz au moins partiellement condensé est renvoyée en tête de la colonne d’épuisement 25 pour fournir du liquide de reflux. Le reste 29 peut se réchauffer dans l’échangeur de chaleur 7 contre le gaz de synthèse 5.  The tank liquid 17 of the column 15 joins the liquid 13 of the separator 9 and the mixture 91 containing between 1 and 3 mol% of hydrogen is sent to the top of a depletion column 25. A top gas 27 of the The exhaust column at least partially condenses in the heat exchanger 23. At least a portion 31 of the at least partially condensed gas is returned to the top of the depletion column 25 to provide reflux liquid. The remainder 29 can be heated in the heat exchanger 7 against the synthesis gas 5.
Le gaz frigorigène 27 qui part se faire refroidir dans l’échangeur de chaleur 23 y subira une condensation au moins partielie. En cas de condensations partielle, il y a création de liquide et de gaz. Il est possible qu'une partie du liquide créé passe par une autre conduite 31 ou alors retombe par le tuyau 27 dont provient le gaz frigorigène à refroidir, pour rejoindre la colonne 25. Dans ce deuxième cas, le tuyau 31 n’est pas nécessaire. Un liquide 33 pris en cuve de la colonne d’épuisement 25 se refroidit dans l’échanger 7 et est envoyé à la colonne de séparation 45. Une autre partie du même liquide 35 se vaporise dans un rebouilleur de cuve 37 et est renvoyé en cuve de la colonne d’épuisement. The refrigerant gas 27 leaving to be cooled in the heat exchanger 23 undergoes at least partial condensation. In case of partial condensation, liquid and gas are created. It is possible that a portion of the liquid created passes through another pipe 31 or then falls through the pipe 27 from which the refrigerant gas to be cooled, to join the column 25. In this second case, the pipe 31 is not necessary . A liquid 33 taken in the bottom of the depletion column 25 cools in the exchange 7 and is sent to the separation column 45. Another part of the same liquid 35 vaporizes in a bottom reboiler 37 and is returned to the tank from the column of exhaustion.
La colonne de séparation comprend plusieurs sections de séparation par distillation et éventuellement une capacité 99. Elle a un rebouilleur de cuve 73 qui sert à chauffer le liquide de cuve 75, le gaz formé étant renvoyé à la cuve. Le liquide de cuve 77 enrichi en méthane est divisé en deux. Une partie 83 se vaporise dans l’échangeur 7 pour former du carburant. Le reste 85 est pressurisée par une pompe 87 et est envoyé en tête de la colonne de lavage 15.  The separation column comprises a plurality of distillation separation sections and optionally a capacity 99. It has a bottom reboiler 73 which serves to heat the bottom liquid 75, the formed gas being returned to the vessel. The tank liquid 77 enriched with methane is divided in two. Part 83 vaporizes in exchanger 7 to form fuel. The remainder 85 is pressurized by a pump 87 and is sent to the top of the washing column 15.
Le gaz de tête de la colonne 43 enrichi en monoxyde de carbone est envoyé à un compresseur de produit 57 qui produit un gaz enrichi en monoxyde de carbone 57. Une partie du gaz enrichi en monoxyde de carbone 61 est refroidie et se divise en deux. Une partie 65 est détendue dans une turbine 67 pour fournir du froid. Le gaz détendu 89 est renvoyé à l’entrée du compresseur 57. Le reste du gaz 69 poursuit son refroidissement dans l’échangeur 7 et sert à réchauffer les rebouilleurs 73 et 37 (débits 93 et 73). Le gaz ayant servi pour le rebouillage est ainsi partiellement condensé et alimente comme débit 97 la capacité 99 en tête de la colonne de séparation 45. Le gaz 41 de la capacité 99 alimente le compresseur 57. Le liquide 47 de la capacité 99 est envoyé à un séparateur de phases 49, le liquide 51 du séparateur sert de fluide frigorigène dans l’échangeur de chaleur 23 pour refroidir les gaz intermédiaires 21 A, 21 B,21 C ainsi que le gaz de tête 27 de la colonne d’épuisement. Le liquide 51 est ainsi vaporisé et renvoyé au séparateur de phases 49 dont le gaz 53 alimente le compresseur 57.  The overhead gas from the carbon monoxide enriched column 43 is fed to a product compressor 57 which produces a gas enriched with carbon monoxide 57. Part of the carbon monoxide enriched gas 61 is cooled and split in half. Part 65 is expanded in a turbine 67 to provide cold. The expanded gas 89 is returned to the inlet of the compressor 57. The remaining gas 69 continues to cool in the exchanger 7 and is used to heat the reboilers 73 and 37 (flow rates 93 and 73). The gas used for the reboiling is thus partially condensed and feeds as the flow 97 the capacity 99 at the top of the separation column 45. The gas 41 of the capacity 99 feeds the compressor 57. The liquid 47 of the capacity 99 is sent to a phase separator 49, the liquid 51 of the separator serves as a refrigerant in the heat exchanger 23 for cooling the intermediate gases 21 A, 21 B, 21 C and the overhead gas 27 of the depletion column. The liquid 51 is thus vaporized and returned to the phase separator 49 whose gas 53 supplies the compressor 57.
Un liquide soutiré de la section de séparation de la colonne de séparation peut remplacer le liquide 47 ou un autre liquide du procédé.  A liquid withdrawn from the separation section of the separation column can replace the liquid 47 or other liquid of the process.
Selon une variante du procédé, illustrée à la Figure 2, la colonne d’épuisement comprenant une section de lavage au méthane, une partie du liquide 85 pressurisé par la pompe 87 étant envoyée en tête de la colonne d’épuisement 25 et une autre partie étant envoyé comme pour la Figure 1 en tête de la colonne de lavage 15.  According to a variant of the process, illustrated in FIG. 2, the exhaustion column comprising a methane washing section, a part of the liquid 85 pressurized by the pump 87 being sent to the top of the depletion column 25 and another part being sent as for Figure 1 at the top of the washing column 15.
Dans ce cas, le gaz 27 soutiré de la colonne d’épuisement 25 est pris au moins un plateau théorique en dessous de la tête de la colonne. Le gaz au moins partiellement condensé dans l’échangeur 23 retourne à la colonne d’épuisement à côté du point de soutirage et le gaz montant dans la partie supérieure de la colonne d’épuisement (section de lavage 25A) devient plus enrichi en hydrogène, permettant de réduire le nombre de plateaux théoriques requis. In this case, the gas 27 withdrawn from the depletion column 25 is taken at least one theoretical plate below the head of the column. The at least partially condensed gas in the exchanger 23 returns to the exhaust column adjacent to the draw-off point and the rising gas in the upper part of the depletion column (washing section 25A) becomes more enriched in hydrogen, to reduce the number of theoretical plates required.
Comme montre la Figure 3, l’invention s’applique également au cas où le procédé n’utilise pas de colonne de lavage au méthane. Ici la première séparation est effectuée simplement par condensation partielle dans le séparateur 9. Le gaz 11 est réchauffé et le liquide appauvri en hydrogène 13 est envoyé à la colonne d’épuisement 25. Celle-ci peut comprendre une section de lavage au méthane, comme pour la Figure 2, ou pas selon les besoins.  As shown in FIG. 3, the invention also applies to the case where the process does not use a methane scrubbing column. Here the first separation is carried out simply by partial condensation in the separator 9. The gas 11 is heated and the hydrogen-depleted liquid 13 is sent to the depletion column 25. This may include a methane wash section, as for Figure 2, or not as needed.
Ici la section de lavage au méthane 25A est présente et donc le gaz 27 soutiré en colonne d’épuisement est pris à un niveau intermédiaire comme pour la Figure 2.  Here the methane wash section 25A is present and thus the gas 27 drawn off in the exhaustion column is taken at an intermediate level as in FIG. 2.
Ainsi tout le méthane pressurisé est envoyé en tête de colonne d’épuisement 25.  Thus all the pressurized methane is sent to the top of the exhaustion column.
En l’absence d’une colonne de lavage 15, l’échangeur de chaleur 23 est simplifié et permet un échange de chaleur entre deux seuls fluides, le gaz à refroidir 27 et le liquide à réchauffer 51.  In the absence of a washing column 15, the heat exchanger 23 is simplified and allows a heat exchange between two single fluids, the gas to be cooled 27 and the liquid to be heated 51.
Si la section 25A est absente, le gaz 27 est pris en tête de colonne 25.  If the section 25A is absent, the gas 27 is taken at the top of the column 25.

Claims

Revendications claims
1. Procédé de séparation d’un gaz de synthèse comprenant de l’hydrogène, du monoxyde de carbone et du méthane et éventuellement d’azote par distillation cryogénique dans lequel : A process for separating a synthesis gas comprising hydrogen, carbon monoxide and methane and optionally nitrogen by cryogenic distillation in which:
i) le gaz de synthèse (1 ,5) est épuré et refroidi jusqu’à une température cryogénique,  i) the synthesis gas (1, 5) is purified and cooled to a cryogenic temperature,
ii) le gaz de synthèse refroidi est séparé par un premier moyen (9, 15) pour produire un liquide appauvri en hydrogène (91 ), la séparation effectuée par le premier moyen est constituée par une étape de lavage dans une colonne de lavage (15) avec au moins une partie du liquide enrichi en méthane soutiré d’une colonne de séparation de monoxyde de carbone et de méthane ayant un condenseur de tête, le condenseur étant refroidi par un cycle de monoxyde de carbone, et  ii) the cooled synthesis gas is separated by a first means (9, 15) to produce a hydrogen-depleted liquid (91), the separation by the first means is a washing step in a washing column (15); ) with at least a portion of the methane enriched liquid withdrawn from a carbon monoxide and methane separation column having an overhead condenser, the condenser being cooled by a carbon monoxide cycle, and
iii) le liquide appauvri en hydrogène est introduit dans la partie supérieure d’une colonne d’épuisement (25) qui comprend également une partie inférieure, iv) un gaz enrichi en hydrogène (27, 29) est soutiré en tête de la colonne d’épuisement,  iii) the hydrogen-depleted liquid is introduced into the upper part of a depletion column (25) which also comprises a lower part; iv) a hydrogen-enriched gas (27, 29) is withdrawn at the top of the column; 'exhaustion,
v) un liquide (33) est soutiré en cuve de la colonne d’épuisement et envoyé à la colonne de séparation (45), un gaz (43) enrichi en monoxyde de carbone et appauvri en méthane est soutiré en tête de la colonne de séparation, un liquide (77) appauvri en monoxyde de carbone et enrichi en méthane est soutiré en cuve de la colonne de séparation, le gaz enrichi en monoxyde de carbone est réchauffé par échange de chaleur avec le gaz de synthèse de l’étape i) pour former un produit (29),  v) a liquid (33) is withdrawn in the bottom of the exhaustion column and sent to the separation column (45), a gas (43) enriched in carbon monoxide and depleted in methane is withdrawn at the top of the column of separation, a liquid (77) depleted in carbon monoxide and enriched in methane is withdrawn in the bottom of the separation column, the carbon monoxide enriched gas is heated by heat exchange with the synthesis gas of step i) to form a product (29),
vi) un gaz (27) soutiré dans la partie supérieure de la colonne d’épuisement est au moins partiellement condensé et renvoyé au moins en partie à la partie supérieure de la colonne d’épuisement caractérisé en ce que le gaz soutiré dans la partie supérieure de la colonne d’épuisement est au moins partiellement condensé dans un échangeur de chaleur (23) qui sert également à refroidir au moins un gaz (210, 211 ) soutiré de la colonne de lavage, l’échangeur de chaleur servant également à réchauffer un fluide frigorigène. vi) a gas (27) withdrawn in the upper part of the exhaust column is at least partially condensed and returned at least partly to the upper part of the depletion column characterized in that the gas withdrawn in the upper part of the exhaust column is at least partially condensed in a heat exchanger (23) which also serves to cool at least one gas (210, 211) withdrawn from the washing column, the heat exchanger also serving to heat a Refrigerant.
2. Procédé selon la revendication 1 dans lequel le gaz (27) soutiré en partie supérieure de la colonne d’épuisement se condense contre au moins une partie (51 ) du liquide de cycle de monoxyde de carbone. 2. The method of claim 1 wherein the gas (27) withdrawn at the top of the exhaust column condenses against at least a portion (51) of the carbon monoxide cycle liquid.
3. Procédé selon l’une des revendications précédentes dans lequel le gaz de synthèse (1 , 3) comprend de l’azote et le liquide soutiré de la colonne d’épuisement (25) ou un fluide dérivé de ce liquide est séparé dans une colonne de déazotation (55), dont le liquide sert à condenser au moins partiellement le gaz de tête de la colonne d’épuisement. 3. Method according to one of the preceding claims wherein the synthesis gas (1, 3) comprises nitrogen and the liquid withdrawn from the depletion column (25) or a fluid derived from this liquid is separated in a denitrogenation column (55), the liquid of which serves to at least partially condense the overhead gas of the depletion column.
4. Procédé selon l’une des revendications précédentes dans lequel le gaz (27) soutiré dans la partie supérieure de la colonne d’épuisement est au moins partiellement condensé par échange de chaleur avec un liquide enrichi en monoxyde de carbone soutiré de la colonne de séparation (45) qui se réchauffe et éventuellement se vaporise au moins partiellement. 4. Method according to one of the preceding claims wherein the gas (27) withdrawn into the upper part of the depletion column is at least partially condensed by heat exchange with a carbon monoxide enriched liquid withdrawn from the column of separating (45) which heats up and optionally vaporises at least partially.
5. Procédé selon la revendication 4 dans lequel le liquide (47) enrichi en monoxyde de carbone est soutiré d’une section de distillation de la colonne de séparation (45) ou d’une capacité formant la tête de la colonne de séparation. The method of claim 4 wherein the carbon monoxide enriched liquid (47) is withdrawn from a distillation section of the separation column (45) or a capacity forming the head of the separation column.
6. Procédé selon l’une des revendications précédentes dans lequel le gaz soutiré de la partie supérieure de la colonne d’épuisement (27) est un gaz de tête de la colonne d’épuisement soutiré à un niveau au-dessus de tout moyen de transfert de chaleur et de masse de la colonne d’épuisement. 6. Method according to one of the preceding claims wherein the gas withdrawn from the top of the depletion column (27) is a top gas of the exhaust column withdrawn at a level above any means of heat and mass transfer from the exhaustion column.
7. Procédé selon l’une des revendications 1 à 6 dans lequel le gaz soutiré de partie supérieure de la colonne d’épuisement est soutiré au moins un plateau théorique en dessous de la tête de la colonne d’épuisement, une partie du liquide enrichi en méthane soutiré de la colonne de séparation étant envoyée à un niveau de la colonne d’épuisement au-dessus du niveau de soutirage du gaz. 7. Method according to one of claims 1 to 6 wherein the gas withdrawn from the top of the depletion column is withdrawn at least one theoretical plate below the head of the depletion column, a portion of the enriched liquid methane withdrawn from the separation column being sent to a level of the depletion column above the gas withdrawal level.
8. Procédé selon l’une des revendications 1 à 6 dans lequel la séparation effectuée par le premier moyen ne comprend pas d’étape de lavage avec un liquide enrichi en méthane. 8. Method according to one of claims 1 to 6 wherein the separation performed by the first means does not include a washing step with a methane enriched liquid.
9. Procédé selon l’une des revendications précédentes qui est tenu en froid par un cycle utilisant le gaz enrichi en monoxyde de carbone provenant de la colonne de séparation (45). 9. Method according to one of the preceding claims which is kept cold by a cycle using the carbon monoxide enriched gas from the separation column (45).
10. Procédé selon l’une des revendications précédentes dans lequel le liquide (17) appauvri en hydrogène contient entre 1 et 3% mol d’hydrogène. 10. Method according to one of the preceding claims wherein the liquid (17) depleted of hydrogen contains between 1 and 3 mol% of hydrogen.
11. Appareil de séparation d’un gaz de synthèse comprenant de l’hydrogène, du monoxyde de carbone, du méthane et éventuellement de l’azote par distillation cryogénique comprenant un échangeur de chaleur (7), un premier moyen de séparation (9, 15) qui est une colonne de lavage au méthane , une colonne d’épuisement (25) et éventuellement une colonne de séparation (45) de monoxyde de carbone et de méthane, des moyens (3) pour épurer le gaz de synthèse, des moyens pour envoyer le gaz épuré se refroidir dans l’échangeur de chaleur jusqu’à une température cryogénique, des moyens pour envoyer le gaz de synthèse refroidi au premier moyen pour produire un liquide appauvri en hydrogène (17), des moyens pour introduire le liquide appauvri en hydrogène dans la partie supérieure de la colonne d’épuisement qui comprend également une partie inférieure, des moyens pour soutirer un gaz enrichi en hydrogène (27) en tête de la colonne d’épuisement, des moyens pour soutirer un liquide (33) en cuve de la colonne d’épuisement, un deuxième échangeur de chaleur (23), des moyens pour y envoyer un gaz (27) soutiré dans la partie supérieure de la colonne d’épuisement et des moyens pour envoyer au moins une partie du gaz au moins partiellement condensé dans le deuxième échangeur de chaleur vers la partie supérieure de la colonne d’épuisement, des moyens pour envoyer le liquide de cuve (33) de colonne d’épuisement (25) à la colonne de séparation de monoxyde de carbone et de méthane (45), des moyens pour soutirer un gaz (43) enrichi en monoxyde de carbone et appauvri en méthane en tête de la colonne de séparation, des moyens pour soutirer un liquide (77) appauvri en monoxyde de carbone et enrichi en méthane en cuve de la colonne de séparation et des moyens pour envoyer le gaz enrichi en monoxyde de carbone se réchauffer dans l’échangeur de chaleur par échange de chaleur avec le gaz de synthèse pour former un produit caractérisé en ce qu’il comprend des moyens pour envoyer au moins un gaz (210, 211 ) soutiré de la colonne de lavage se refroidir dans le deuxième échangeur de chaleur et des moyens pour envoyer au moins un fluide frigorigène se réchauffer dans le deuxième échangeur de chaleur. 11. Apparatus for separating a synthesis gas comprising hydrogen, carbon monoxide, methane and optionally nitrogen by cryogenic distillation comprising a heat exchanger (7), a first separation means (9, 15) which is a methane scrubbing column, a depletion column (25) and optionally a separation column (45) of carbon monoxide and methane, means (3) for purifying the synthesis gas, means for sending the purified gas to cool in the heat exchanger to a cryogenic temperature, means for sending the cooled synthesis gas to the first means for producing a hydrogen-depleted liquid (17), means for introducing the depleted liquid in hydrogen in the upper part of the depletion column which also comprises a lower part, means for withdrawing a hydrogen-enriched gas (27) at the top of the depletion column, means for drawing off a liquid (33) in the bottom of the exhaustion column, a second heat exchanger (23), means for sending a gas (27) withdrawn into the upper part of the depletion column and means for sending to the at least a portion of the at least partially condensed gas in the second heat exchanger to the top of the depletion column, means for supplying the spent-tank liquid (33) to the separation column (25) of carbon monoxide and methane (45), means for withdrawing a gas (43) enriched in carbon monoxide and depleted of methane at the top of the separation column, means for withdrawing a liquid (77) depleted in carbon monoxide carbon and enriched in methane in the bottom of the separation column and means for sending the enriched carbon monoxide gas to heat in the heat exchanger by heat exchange with the synthesis gas to form a product characterized in that it comprises means for sending at least one gas (210, 211 ) withdrawn from the washing column to cool in the second heat exchanger and means for sending at least one refrigerant to heat in the second heat exchanger.
12. Appareil selon la revendication 11 dans lequel le deuxième échangeur de chaleur est un échangeur de chaleur indirecte (23). Apparatus according to claim 11 wherein the second heat exchanger is an indirect heat exchanger (23).
13. Appareil selon la revendication 11 ou 12 comprenant des moyens pour soutirer le gaz en partie supérieure de la colonne d’épuisement et pour l’envoyer se condenser contre au moins une partie du liquide (47,51 ) de cycle de monoxyde de carbone. Apparatus according to claim 11 or 12 including means for withdrawing gas from the top of the exhaust column and condensing it against at least a portion of the carbon monoxide cycle liquid (47, 51). .
14. Appareil selon la revendication 11 , 12 ou 13 où le fluide frigorigène est un liquide (47,51 ) enrichi en monoxyde de carbone et comprenant des moyens pour soutirer le liquide enrichi en monoxyde de carbone est d’une section de distillation de la colonne de séparation ou d’une capacité formant la tête de la colonne de séparation. 14. Apparatus according to claim 11, 12 or 13 wherein the refrigerant is a liquid (47,51) enriched in carbon monoxide and comprising means for withdrawing the carbon monoxide enriched liquid is a distillation section of the separation column or a capacity forming the head of the separation column.
15. Appareil selon l’une des revendications 11 à 14 dans lequel les moyens de maintien en froid du procédé comprennent un cycle (47,51 ,57,67) utilisant le gaz enrichi en monoxyde de carbone provenant de la colonne de séparation. 15. Apparatus according to one of claims 11 to 14 wherein the cold holding means of the method comprises a cycle (47,51, 57,67) using the carbon monoxide enriched gas from the separation column.
PCT/FR2019/050624 2018-03-21 2019-03-20 Method and appliance for separating a synthesis gas by cryogenic distillation WO2019180374A1 (en)

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Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0313883A2 (en) * 1987-10-27 1989-05-03 Linde Aktiengesellschaft Hydrogen-carbonmonoxide separation process using partial condensation at low temperatures
EP0317851A2 (en) 1987-11-24 1989-05-31 Linde Aktiengesellschaft Process and apparatus for separating a gas mixture
EP0465366A1 (en) 1990-07-04 1992-01-08 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Process and installation for the simultaneous production of methane and carbon monoxide
US20010027858A1 (en) * 2000-04-07 2001-10-11 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Liquid gas manifold for a matter and/or heat exchange column, and column using such a manifold
FR2807504A1 (en) 2000-04-07 2001-10-12 Air Liquide COLUMN FOR CRYOGENIC SEPARATION OF GASEOUS MIXTURES AND METHOD FOR CRYOGENIC SEPARATION OF A HYDROGEN AND CO CONTAINING MIXTURE USING THE SAME
EP2122282A2 (en) * 2006-12-21 2009-11-25 L'AIR LIQUIDE, Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude Method for separating a mixture of carbon monoxide, methane, hydrogen, and optionally nitrogen by cryogenic distillation
WO2013178901A2 (en) 2012-05-31 2013-12-05 L'air Liquide,Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Device and method for cryogenically separating a mixture of carbon monoxide and methane plus hydrogen and/or nitrogen

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2655137B1 (en) * 1989-11-28 1992-10-16 Air Liquide AIR DISTILLATION PROCESS AND INSTALLATION WITH ARGON PRODUCTION.
FR2728663B1 (en) * 1994-12-23 1997-01-24 Air Liquide PROCESS FOR SEPARATING A GASEOUS MIXTURE BY CRYOGENIC DISTILLATION
EP2149769A1 (en) * 2008-07-31 2010-02-03 BP Alternative Energy International Limited Separation of carbon dioxide and hydrogen
CN101659316A (en) * 2009-09-15 2010-03-03 王德荣 Marine inert gases system
CN102435045A (en) * 2011-12-14 2012-05-02 杭州中泰深冷技术股份有限公司 Liquid nitrogen washing purified synthetic gas and device for cryogenically separating and recovering LNG (liquefied natural gas) thereof
CN104445272B (en) * 2014-11-28 2016-04-27 王文领 A kind of conversion gas phlegma comprehensive reutilization method containing ammonia, carbonic acid gas

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0313883A2 (en) * 1987-10-27 1989-05-03 Linde Aktiengesellschaft Hydrogen-carbonmonoxide separation process using partial condensation at low temperatures
EP0317851A2 (en) 1987-11-24 1989-05-31 Linde Aktiengesellschaft Process and apparatus for separating a gas mixture
EP0465366A1 (en) 1990-07-04 1992-01-08 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Process and installation for the simultaneous production of methane and carbon monoxide
US20010027858A1 (en) * 2000-04-07 2001-10-11 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Liquid gas manifold for a matter and/or heat exchange column, and column using such a manifold
FR2807504A1 (en) 2000-04-07 2001-10-12 Air Liquide COLUMN FOR CRYOGENIC SEPARATION OF GASEOUS MIXTURES AND METHOD FOR CRYOGENIC SEPARATION OF A HYDROGEN AND CO CONTAINING MIXTURE USING THE SAME
FR2807505A1 (en) 2000-04-07 2001-10-12 Air Liquide LIQUID-GAS DISPENSER FOR MATERIAL AND / OR HEAT EXCHANGE COLUMN, AND COLUMN USING SUCH A DISPENSER
EP2122282A2 (en) * 2006-12-21 2009-11-25 L'AIR LIQUIDE, Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude Method for separating a mixture of carbon monoxide, methane, hydrogen, and optionally nitrogen by cryogenic distillation
WO2013178901A2 (en) 2012-05-31 2013-12-05 L'air Liquide,Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Device and method for cryogenically separating a mixture of carbon monoxide and methane plus hydrogen and/or nitrogen

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