US3494751A - Process for the fractionation of natural gas - Google Patents

Process for the fractionation of natural gas Download PDF

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Publication number
US3494751A
US3494751A US69854A US3494751DA US3494751A US 3494751 A US3494751 A US 3494751A US 69854 A US69854 A US 69854A US 3494751D A US3494751D A US 3494751DA US 3494751 A US3494751 A US 3494751A
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United States
Prior art keywords
column
natural gas
methane
fraction
fractionation
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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.)
Expired - Lifetime
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US69854A
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English (en)
Inventor
Martin Friedrich Wilhe Streich
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Messer Griesheim GmbH
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Messer Griesheim GmbH
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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
    • F25J3/0228—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
    • F25J3/0238—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 2 carbon atoms or more
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C7/00—Purification; Separation; Use of additives
    • C07C7/04—Purification; Separation; Use of additives by distillation
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
    • C10G5/00—Recovery of liquid hydrocarbon mixtures from gases, e.g. natural gas
    • C10G5/06—Recovery of liquid hydrocarbon mixtures from gases, e.g. natural gas by cooling or compressing
    • 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
    • F25J3/0209—Natural gas or substitute natural 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
    • F25J2200/00—Processes or apparatus using separation by rectification
    • F25J2200/04—Processes or apparatus using separation by rectification in a dual pressure main column system
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2200/00—Processes or apparatus using separation by rectification
    • F25J2200/70—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
    • 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
    • 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
    • F25J2270/90—External refrigeration, e.g. conventional closed-loop mechanical refrigeration unit using Freon or NH3, unspecified external refrigeration

Definitions

  • a process for the fractionation of a gas mixture comprising methane and higher boiling hydrocarbons includes rectification in a stripping column wherein a sump fraction and a head fraction are produced in the column and the reflux necessary for performing the rectification is produced by cooling the head fraction by at least partly vaporizing the sump fraction under reduced pressure.
  • the present invention is concerned with a new and improved process for the fractionatio of natural gas.
  • high grade natural gas contains the heavy paraffin hydrocarbons in more or less high concentrations, the separation of which may be of interest for various reasons.
  • the calorific value of natural gas can be adjusted to a desired value by separating the heavy hydrocarbons, the complete separation of ethane frequently not being carried out in order to improve the calorific value.
  • the heavy hydrocarbons constitute a potential starting material for a petrochemical industry situated near the pipeline or for the liquid gas market.
  • a process is known in which the heavy hydrocarbons are separated by partial condensation or are concentrated by two-stage partial evaporation.
  • the degree of separation of the higher hydrocarbons is determined by the initial concentrations, the fractionation pressure and the fractionation temperature, so that it is not freely selectable in respect of the individual components.
  • This method is, for example, disadvantageous when low yields of ethane but high yields of propane and all higher boiling hydrocarbons are desired.
  • processes in which the natural gas is partially condensed in a plurality of stages at different temperatures, afiord a certain, although likewise limited latitude.
  • a process in which a liquefied natural gas is introduced into the middle portion of a fractionation column and is separated therein into a high boiling sump liquid and a head gas having a high methane content, the reflux for the top portion of the column being produced by partial liquefaction of the head gas by means of cold natural gas.
  • This process is based on natural gas supplied in liquid form.
  • Another method of fractionating natural gas likewise makes use of separation by rectification and consists in that the cooling for producing the reflux is supplied by at least partial expansion of the methane-containing head gas in a vortex tube.
  • the sump of the 3,494,751 Patented Feb. 10, 1970 stripping part of the column is heated.
  • This method is disadvantageous when there is no use, under reduced pressure, for the quantity of methane produced by the expansion and this methane must, for example, again be recompressed to the pipeline pressure.
  • the evaporation of the sump liquid in the process according to the present invention is advantageously effected only to such an extent that methane can be removed in the following demethanising column without the necessity of incorporating a concentration or intensification part in the head of the demethanising column.
  • the process according to the present invention aflords particular advantages, especially in the fractionation of natural gas under high pressure, because the degree of separation of heavy hydrocarbons is higher for a given quantity of liquid than in the method using partial condensation.
  • the expense of producing the reflux is lower, provided that the starting material is gaseous natural gas, and the demethanisation of the heavy hydrocarbons can be effected more easily, because this is carried out under reduced pressure with more favourable relative volatilities.
  • FIGURE 1 illustrates a flow diagram of an installation for the limited separation, from natural gas, of ethane and for the almost complete separation of all hydrocarbons having higher boiling points than ethane;
  • FIGURE 2 illustrates a flow diagram of a portion of the installation according to FIGURE 1 in which, in contradistinction to FIGURE 1, the natural gas is expanded before entering the column and is then fed into the middle of the rectifying column.
  • the natural gas fractionating plant which is illustrated in FIGURE 1 and which can be used for carrying out the process according to the present invention, comprises a rectifying column 7, a demethanisation column 21, driers 3A and 3B, a countercurrent vessel 5, a reflux condenser 9 and a re-compressor 27.
  • a rectifying column 7 a demethanisation column 21, driers 3A and 3B
  • a countercurrent vessel 5 a reflux condenser 9
  • a re-compressor 27 In the plant illustrated in FIG- URE 2, in addition to the re-compressor 27, there is provided an additional re-compressor 37.
  • the turbine 35 (FIGURE 2) serves for the partial expansion of the natural gas.
  • the quantity wanted for the fractionation is branched off and fed through pipe 2 to one of the two driers 3A, 3B, and possibly to additional purification units (not illustrated).
  • the purified gas is then available in pipe 4, upstream of the low temperature plant, at, for example, a pressure of 50 3 atmospheres and a temperature of 20 C.
  • a typical composition of such-a gas is:
  • the liquid collecting in the sump of the column 7 has a composition of:
  • the heavy hydrocarbon fraction is freed of methane to the desired extent at a pressure of 21 atmospheres and then passed through pipe 24 to the remainder of the fractionating plant.
  • the heat for the upward flow of the vapour is supplied in column 21 via two separate heat exchangers 22 and 23.
  • the use of two heat exchangers 'permits a more'favourable adaptation of the working to'the equilibrium curve or the recovery of a certain amount of cooling at a lower temperature level, which is, for example, advantageous for the transformation of the cooling to the level of the reflux condenser 9.
  • the unfractionated natural gas passes from the line section 1, through valve 30, directly to the line section 31.
  • the cooling required in the reflux condenser 9 additionally to the sump cooling can be supplied in conventional manner through pipe 33, for example, by using a propane-ethane cascade or by means, of cold produced by pre-expansion of the natural gas, as illustrated in FIG- URE 2.
  • the natural gas is expanded before entering the column 7.
  • all the methane must be re-compressed in the compressor 37.
  • a part of this compression energy can be supplied by the turbine 35.
  • Introduction of the natural gas into the middle of the column 7 permits extensive methane separation in column 7 itself.
  • the necessary gas heat is supplied via the heat exchanger 38.
  • the remainder of the cooling for the reflux condenser is supplied by partial expansion of the natural gas in the turbine 35.
  • the first methane fraction is returned via the reflux condenser 9 and gives up sensible cold.
US69854A 1966-02-05 1967-01-17 Process for the fractionation of natural gas Expired - Lifetime US3494751A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DEM68286A DE1302036B (de) 1966-02-05 1966-02-05 Verfahren zur Zerlegung eines aus Methan und schwersiedenden Kohlenwasserstoffen bestehenden Gasgemisches, insbesondere Erdgas, mittels Rektifikation

Publications (1)

Publication Number Publication Date
US3494751A true US3494751A (en) 1970-02-10

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ID=7312547

Family Applications (1)

Application Number Title Priority Date Filing Date
US69854A Expired - Lifetime US3494751A (en) 1966-02-05 1967-01-17 Process for the fractionation of natural gas

Country Status (5)

Country Link
US (1) US3494751A (fr)
DE (1) DE1302036B (fr)
FR (1) FR1515270A (fr)
GB (1) GB1109772A (fr)
NL (1) NL151122B (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3989478A (en) * 1973-09-27 1976-11-02 Petrocarbon Developments Limited Producing gaseous fuels of high calorific value
US4405449A (en) * 1980-08-29 1983-09-20 Procon International Inc. Process for vapor-liquid contacting and fractional distillation
US5026952A (en) * 1986-08-06 1991-06-25 Linde Aktiengesellschaft Process for separating C2 + or C3 + or C4 hydrocarbons from a gaseous mixture
US6735979B2 (en) * 2000-09-26 2004-05-18 Institut Francais Du Petrole Process for pretreating a natural gas containing acid gases

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2557171A (en) * 1946-11-12 1951-06-19 Pritchard & Co J F Method of treating natural gas
US2658360A (en) * 1946-05-08 1953-11-10 Chemical Foundation Inc Transportation of natural gas
US2712730A (en) * 1951-10-11 1955-07-12 Pritchard & Co J F Method of and apparatus for storing gases
US2771149A (en) * 1952-10-13 1956-11-20 Phillips Petroleum Co Controlling heat value of a fuel gas in a gas separation system
US3057706A (en) * 1958-06-25 1962-10-09 Conch Int Methane Ltd Adjusting the heating value and specific gravity of natural gas
US3241933A (en) * 1961-08-17 1966-03-22 Conch Int Methane Ltd Process for the reforming of natural gas
US3331214A (en) * 1965-03-22 1967-07-18 Conch Int Methane Ltd Method for liquefying and storing natural gas and controlling the b.t.u. content
US3407052A (en) * 1966-08-17 1968-10-22 Conch Int Methane Ltd Natural gas liquefaction with controlled b.t.u. content

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB191018698A (en) * 1912-12-13 1910-11-10 Air Liquide Improvements relating to the Dessication of Air and other Gases.
FR562216A (fr) * 1922-04-04 1923-11-07 Air Liquide Procédé d'extraction d'hydrogène par liquéfaction partielle des gaz d'eau, de ville, de fours à coke et autres
DE460927C (de) * 1922-05-27 1928-06-09 Arthur Seligmann Dr Ing Verfahren zur Verfluessigung und Trennung schwer kondensierbarer Gase und Gasgemische unter Zuhilfenahme aeusserer Arbeitsleistung
US2213338A (en) * 1937-01-02 1940-09-03 Baufre William Lane De Method and apparatus for fractionating gaseous mixtures
US3186182A (en) * 1963-05-27 1965-06-01 Phillips Petroleum Co Low-temperature, low-pressure separation of gases

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2658360A (en) * 1946-05-08 1953-11-10 Chemical Foundation Inc Transportation of natural gas
US2557171A (en) * 1946-11-12 1951-06-19 Pritchard & Co J F Method of treating natural gas
US2712730A (en) * 1951-10-11 1955-07-12 Pritchard & Co J F Method of and apparatus for storing gases
US2771149A (en) * 1952-10-13 1956-11-20 Phillips Petroleum Co Controlling heat value of a fuel gas in a gas separation system
US3057706A (en) * 1958-06-25 1962-10-09 Conch Int Methane Ltd Adjusting the heating value and specific gravity of natural gas
US3241933A (en) * 1961-08-17 1966-03-22 Conch Int Methane Ltd Process for the reforming of natural gas
US3331214A (en) * 1965-03-22 1967-07-18 Conch Int Methane Ltd Method for liquefying and storing natural gas and controlling the b.t.u. content
US3407052A (en) * 1966-08-17 1968-10-22 Conch Int Methane Ltd Natural gas liquefaction with controlled b.t.u. content

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3989478A (en) * 1973-09-27 1976-11-02 Petrocarbon Developments Limited Producing gaseous fuels of high calorific value
US4405449A (en) * 1980-08-29 1983-09-20 Procon International Inc. Process for vapor-liquid contacting and fractional distillation
US5026952A (en) * 1986-08-06 1991-06-25 Linde Aktiengesellschaft Process for separating C2 + or C3 + or C4 hydrocarbons from a gaseous mixture
US6735979B2 (en) * 2000-09-26 2004-05-18 Institut Francais Du Petrole Process for pretreating a natural gas containing acid gases

Also Published As

Publication number Publication date
NL6700947A (fr) 1967-08-07
FR1515270A (fr) 1968-03-01
DE1302036B (de) 1969-10-16
NL151122B (nl) 1976-10-15
GB1109772A (en) 1968-04-18

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