EP0186555A1 - Selbstkühlendes Verfahren zur Extraktion von schweren Kohlenwasserstofffraktionen - Google Patents

Selbstkühlendes Verfahren zur Extraktion von schweren Kohlenwasserstofffraktionen Download PDF

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Publication number
EP0186555A1
EP0186555A1 EP85402339A EP85402339A EP0186555A1 EP 0186555 A1 EP0186555 A1 EP 0186555A1 EP 85402339 A EP85402339 A EP 85402339A EP 85402339 A EP85402339 A EP 85402339A EP 0186555 A1 EP0186555 A1 EP 0186555A1
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EP
European Patent Office
Prior art keywords
gas
solvent
fraction
phase
heavy
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EP85402339A
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English (en)
French (fr)
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EP0186555B1 (de
Inventor
Joseph Larue
Alexandre Rojey
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IFP Energies Nouvelles IFPEN
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IFP Energies Nouvelles IFPEN
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Priority to AT85402339T priority Critical patent/ATE33673T1/de
Publication of EP0186555A1 publication Critical patent/EP0186555A1/de
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Publication of EP0186555B1 publication Critical patent/EP0186555B1/de
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    • 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
    • C10G5/04—Recovery of liquid hydrocarbon mixtures from gases, e.g. natural gas with liquid absorbents
    • 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
    • C10G2300/00—Aspects relating to hydrocarbon processing covered by groups C10G1/00 - C10G99/00
    • C10G2300/10—Feedstock materials
    • C10G2300/1025—Natural gas

Definitions

  • the present invention relates to a new self-cooled process, based on the principle of absorption-desorption in a solvent and making it possible to extract hydrocarbons of which the number of carbon atoms is at least equal to two, for example from 2 to 6 , of a gas which contains them.
  • This process can find applications in field gas treatment if the gas to be treated is for example a natural gas or an associated gas, and / or in refining and petrochemicals.
  • Gas expansion is the simplest of the processes; it has the drawback of greatly lowering the pressure of the gas and leads to a low recovery rate.
  • the gas is brought into contact with a solvent, in which the heaviest constituents of the gas are absorbed preferentially; the enriched solvent is then subjected to expansion and / or heating to be regenerated and to release the absorbed constituents; certain stages of these processes, in particular the absorption and recovery of heavy fractions, can be refrigerated by an external refrigeration cycle.
  • the most conventional method consists in cooling the gas using an external refrigerating machine; it allows working in a wide range of temperature and pressure and leads to significant recovery.
  • the present process applies in particular to the treatment of a gas containing a light fraction and a heavy fraction, the light fraction containing at least one light constituent of the group comprising hydrogen, nitrogen and hydrocarbons having from 1 to 2 carbon atoms and the heavy fraction containing at least one heavy constituent from the group comprising hydrocarbons having from 2 to 6 carbon atoms, provided that, when the light fraction contains a hydrocarbon containing 2 carbon atoms, the heavy fraction contains at least a hydrocarbon having 3 to 6 carbon atoms.
  • Non-distillable means that the major part, and preferably at least 90%, most often at least 98%, of the liquid phase is not vaporized under the operating conditions of the process.
  • majority (or selective) absorption of the heavy fraction it is meant that the relative proportion of heavy fraction absorbed is greater than the relative proportion of light fraction absorbed.
  • the majority lowering of the heavy fraction gas content means that the relative lowering of the heavy fraction gas content is greater than the relative lowering of the light fraction gas content.
  • the condensate in step (g), can receive heat not only from absorption (step a), but also from condensation (step f) and circulating fluids: depleted solution of the step (e) and separate gas in step (b).
  • the absorption (step a) is carried out in two stages: the mixture of gas and liquid phase yields heat first to a medium external to the process and then to the condensate of step (g).
  • step f it is preferable to carry out the condensation (step f) in two stages: the gaseous phase releases heat first towards the external medium then towards the condensate expanded in step (g).
  • the heavy fraction desorbed may come out entirely vaporized or only partially vaporized.
  • a liquid / vapor fractionation will make it possible to collect a cordensate, for example butane, and the remaining gaseous fraction may be either collected or recycled to be again treated as a mixture with the fresh gas.
  • steps (a) and / or (f) can advantageously take place at least partially at a temperature below room temperature thanks to the cold produced in step (g) .
  • the gas to be treated arrives via line 1; it is mixed with a gas flow coming from line 13; the total gas flow, flowing in line 23, is brought into contact with a solvent phase coming from line 8, and an addition of solvent coming from line 24.
  • GR rich gas
  • the mixture circulating in line 21 enters the exchanger A in which it is cooled by heat exchange with an external fluid entering through the line 25 and emerging through line 26; during this heat exchange, part of the heaviest components of the gas is absorbed in the solvent; the mixture leaves the exchanger A via line 2, and enters the heat exchanger E2 in which it cools; another fraction of the heaviest components of the gas is absorbed in the solvent; the mixture leaves the exchanger E2 via line 17 and enters the tank B2 in which the gas and the liquid are separated; the gas, depleted in heavy constituents, called lean gas (GP), leaves the cylinder B2 via line 19, enters the exchanger E2 in which it heats up by heat exchange and leaves the process through line 16.
  • GP lean gas
  • the liquid phase leaves the balloon B2 via line 18, passes through pump P which raises the pressure, enters via line 20 in exchanger E2 in which it heats up by heat exchange, exits through line 3, enters heat exchanger El in which it heats up through heat exchange, exits through line 4, enters heat exchanger G in which it heats up through heat exchange with a fluid external hot which enters the exchanger G via the line 29 and leaves it via the line 30.
  • SR rich solution
  • SP solvent
  • LPG vapor phase
  • the at least partially condensed fluid leaves the exchanger C via the line 10 enters the exchanger E2 in which it cools, which causes total condensation and / or sub-cooling, exits through the line 15, is expanded in valve V1, enters via line 11 into exchanger E1 in which it vaporizes by heat exchange producing cold, exits through line 12 partially vaporized, and enters balloon B3 in which the two liquid phases and steam are separated; the liquid phase, which contains heavy constituents extracted from the treated gas, leaves the process via line 14, the vapor phase leaves the flask B3 through line 13 and is mixed with the gas to be treated coming from line 1.
  • the absorption of the heavy constituents of the treated gas in the solvent is carried out partially at low temperature; on the other hand, the condensation of the desorbed heavy fractions can be completely carried out at a temperature close to ambient, that is to say that the flow leaving the exchanger C via line 10 can be completely in the liquid state if the pressure in this area of the process is high enough.
  • the rich gas which can be treated by the process according to the invention is a petroleum gas which can come from a production field (natural gas or associated gas) or be a refinery gas or from a petrochemical unit.
  • This gas can contain hydrocarbons, saturated or not, straight chain, branched or cyclic, such as for example methane, ethane, propane, butane, pentane, hexane, ethylene, propylene, butene, acetylene. Heavier constituents may be present, for example heptane, octane, nonane and decane.
  • the proportions of hydrocarbons present are lower as their number of carbon atoms is larger.
  • the method according to the invention makes it possible to recover at least one part of the hydrocarbons other than methane.
  • the gas may also contain some constituents which are not part of the hydrocarbon family and which are not recovered by the process, such as for example hydrogen, nitrogen, carbon dioxide, hydrogen sulfide, l 'water.
  • the solvent used in the process according to the invention is chosen so as to allow the absorption of the heavy constituents of the gas; it is preferably characterized by a boiling point at least 50 ° C and preferably at least 100 ° C higher than that of the heaviest component of the heavy fraction of the gas; it can be a pure body or a mixture. It can be chosen from hydrocarbons; in this case the number of carbon atoms is at least equal to 6; the hydrocarbons can be paraffinic, aromatic or naphthenic, and can be chosen, for example, from oils.
  • the external cooling fluid circulating in the exchangers A and C can be water or ambient air or a fluid coming from a refrigeration machine external to the process.
  • certain exchangers can be of multiple flow: 3 for E1, 5 for E2, but it is also possible to exchange between fluids in pairs.
  • the method according to the invention can treat gases whose pressure is preferably between 0.1 and 20 MPa.
  • Pressure from stages (a, b and g) is preferably within the same domain and that of stages (c, d and f) preferably between 0.2 and 20 MPa, with the additional condition that the pressure of stages (c, d and f) is greater by at least 0.1 MPa, preferably by at least 0.5 MPa, than that of steps (a, b and g).
  • the cooling can precede or follow the pressure reduction: the pressure from step (d) is then passed to that of step (a).
  • the heat supplied to the process in the exchanger G, to carry out the desorption of the absorbed constituents, is at a temperature level preferably between 100 and 300 ° C.
  • the cold produced by the vaporization of a part of the absorbed constituents and which serves to cool the absorption of a part of the heavy constituents of the rich gas and / or to condense said heavy constituents reseparated from the solvent is at a temperature level preferably between 10 and -50 ° C.
  • the gas to be treated enters the process through line 1; its composition is given in Table I; its temperature is 35 ° C, its pressure is 0.15 MPa absolute, its flow rate is 1184 kg / h. It is mixed with the gas coming from line 13 whose flow rate is 1264 kg / h, and with the solvent coming from line 8 whose flow rate is 6650 kg / h; the makeup of solvent provided by line 24 is 27 kg / h.
  • the solvent used is a paraffinic oil whose normal boiling temperature is between 300 and 350 ° C.
  • the gas and solvent mixture passes through the exchanger A which is cooled by cooling water; at the outlet of the exchanger A, the mixture is at a temperature of 35 ° C. It enters the exchanger E2, in which it is cooled down to a temperature of -10 ° C.
  • the two liquid and vapor phases are separated in the flask B2; the gas which has not been absorbed, called lean gas and the composition of which is given in Table 1, leaves the cylinder B2 via line 19, passes through the exchanger E2, and leaves the process at a temperature of 30 ° C. via the line 16; its flow rate is 872 kg / h.
  • the solvent phase enriched in absorbed constituents called rich solution leaves the tank B2 via line 18, passes through the pump P which raises its pressure to 0.74 MPa; it enters the exchanger E2 in which it heats up, exits via line 3, enters the exchanger El in which it heats up, exits through line 4, enters the exchanger G in which it heats up by exchange thermal with a fluid external hot, comes out through line 5 at a temperature of 200 ° C, partially vaporized.
  • tank B1 The two liquid and vapor phases are separated in tank B1; the liquid phase, rich in solvent called lean solution, leaves tank B1 through line 6, enters exchanger E1 in which it cools, exits through line 7, crosses valve V2 undergoing a pressure loss which reduces its pressure substantially to the value of that of the rich gas at the inlet of the process and passes through line 8 to be brought back into contact with the gas to be treated.
  • the vapor phase of the flask B3 leaves through line 13 and is mixed with the rich gas.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Gas Separation By Absorption (AREA)
  • Production Of Liquid Hydrocarbon Mixture For Refining Petroleum (AREA)
  • Vaporization, Distillation, Condensation, Sublimation, And Cold Traps (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
EP85402339A 1984-12-18 1985-11-28 Selbstkühlendes Verfahren zur Extraktion von schweren Kohlenwasserstofffraktionen Expired EP0186555B1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT85402339T ATE33673T1 (de) 1984-12-18 1985-11-28 Selbstkuehlendes verfahren zur extraktion von schweren kohlenwasserstofffraktionen.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8419500 1984-12-18
FR8419500A FR2574811B1 (fr) 1984-12-18 1984-12-18 Nouveau procede autorefrigere d'extraction de fractions lourdes d'hydrocarbures

Publications (2)

Publication Number Publication Date
EP0186555A1 true EP0186555A1 (de) 1986-07-02
EP0186555B1 EP0186555B1 (de) 1988-04-20

Family

ID=9310802

Family Applications (1)

Application Number Title Priority Date Filing Date
EP85402339A Expired EP0186555B1 (de) 1984-12-18 1985-11-28 Selbstkühlendes Verfahren zur Extraktion von schweren Kohlenwasserstofffraktionen

Country Status (7)

Country Link
US (1) US4822948A (de)
EP (1) EP0186555B1 (de)
JP (1) JPS61151297A (de)
AT (1) ATE33673T1 (de)
CA (1) CA1281994C (de)
DE (1) DE3562270D1 (de)
FR (1) FR2574811B1 (de)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1052746C (zh) * 1994-12-24 2000-05-24 中国科学院新疆化学研究所 油田井口汽中无分离轻烃的综合深加工工艺
US5481060A (en) * 1995-04-20 1996-01-02 Uop Process for the removal of heavy hydrocarbonaceous co-products from a vapor effluent from a normally gaseous hydrocarbon dehydrogenation reaction zone
IT201600081851A1 (it) 2016-08-03 2018-02-03 Danieli Off Mecc Metodo ed apparato per produrre ferro di riduzione diretta utilizzando un pretrattamento catalitico di idrocarburi come una sorgente di gas di riduzione
CN110404387A (zh) * 2019-06-19 2019-11-05 河北工程大学 太阳能辅助燃煤机组co2资源化利用系统及装置

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1507634A (en) * 1921-08-29 1924-09-09 Carbide & Carbon Chem Corp Process of making gasoline
US3188287A (en) * 1961-09-07 1965-06-08 Gas Processors Inc Oil absorption process
US3255105A (en) * 1962-12-10 1966-06-07 Phillips Petroleum Co Natural gasoline recovery process control method
US3272735A (en) * 1964-02-03 1966-09-13 Phillips Petroleum Co Oil removal from liquid refrigerant
US3393527A (en) * 1966-01-03 1968-07-23 Pritchard & Co J F Method of fractionating natural gas to remove heavy hydrocarbons therefrom
US4421535A (en) * 1982-05-03 1983-12-20 El Paso Hydrocarbons Company Process for recovery of natural gas liquids from a sweetened natural gas stream
GB2139111A (en) * 1983-04-29 1984-11-07 Inst Francais Du Petrole Process for fractionating a multi-component gaseous mixture

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2762453A (en) * 1951-11-01 1956-09-11 Monsanto Chemicals Separation of acetylene gases
US2794516A (en) * 1955-10-10 1957-06-04 Dow Chemical Co Solvent and process for separating acetylene from gas mixture
US3098107A (en) * 1959-05-22 1963-07-16 Linde Eismasch Ag Method for producing ethylene
US3943185A (en) * 1974-05-28 1976-03-09 Petro-Tex Chemical Corporation Diolefin production and purification
US4334102A (en) * 1981-04-02 1982-06-08 Allied Corporation Removing liquid hydrocarbons from polyether solvents

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1507634A (en) * 1921-08-29 1924-09-09 Carbide & Carbon Chem Corp Process of making gasoline
US3188287A (en) * 1961-09-07 1965-06-08 Gas Processors Inc Oil absorption process
US3255105A (en) * 1962-12-10 1966-06-07 Phillips Petroleum Co Natural gasoline recovery process control method
US3272735A (en) * 1964-02-03 1966-09-13 Phillips Petroleum Co Oil removal from liquid refrigerant
US3393527A (en) * 1966-01-03 1968-07-23 Pritchard & Co J F Method of fractionating natural gas to remove heavy hydrocarbons therefrom
US4421535A (en) * 1982-05-03 1983-12-20 El Paso Hydrocarbons Company Process for recovery of natural gas liquids from a sweetened natural gas stream
GB2139111A (en) * 1983-04-29 1984-11-07 Inst Francais Du Petrole Process for fractionating a multi-component gaseous mixture

Also Published As

Publication number Publication date
JPS61151297A (ja) 1986-07-09
EP0186555B1 (de) 1988-04-20
US4822948A (en) 1989-04-18
DE3562270D1 (en) 1988-05-26
CA1281994C (fr) 1991-03-26
FR2574811B1 (fr) 1988-01-08
ATE33673T1 (de) 1988-05-15
FR2574811A1 (fr) 1986-06-20

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