EP4345406A1 - Anlage und verfahren zur abtrennung von flüssiggas aus brenngas durch kryogene destillation - Google Patents

Anlage und verfahren zur abtrennung von flüssiggas aus brenngas durch kryogene destillation Download PDF

Info

Publication number
EP4345406A1
EP4345406A1 EP22198757.1A EP22198757A EP4345406A1 EP 4345406 A1 EP4345406 A1 EP 4345406A1 EP 22198757 A EP22198757 A EP 22198757A EP 4345406 A1 EP4345406 A1 EP 4345406A1
Authority
EP
European Patent Office
Prior art keywords
gas
condenser
outlet line
line
distillation column
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
EP22198757.1A
Other languages
English (en)
French (fr)
Inventor
Gary R. MARTIN
Shraddha KARALE
Himanshu Misra
Ashishkumar SHAH
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sulzer Management AG
Original Assignee
Sulzer Management AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Sulzer Management AG filed Critical Sulzer Management AG
Priority to EP22198757.1A priority Critical patent/EP4345406A1/de
Priority to PCT/EP2023/074787 priority patent/WO2024068241A1/en
Publication of EP4345406A1 publication Critical patent/EP4345406A1/de
Pending legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
    • F25J3/0228—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
    • F25J3/0204—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
    • F25J3/0204—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
    • F25J3/0219—Refinery gas, cracking gas, coke oven gas, gaseous mixtures containing aliphatic unsaturated CnHm or gaseous mixtures of undefined nature
    • 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
    • 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
    • F25J3/0242—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 3 carbon atoms 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
    • F25J2200/02—Processes or apparatus using separation by rectification in a single 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
    • F25J2200/40—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
    • F25J2200/74—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
    • F25J2205/00—Processes or apparatus using other separation and/or other processing means
    • F25J2205/02—Processes or apparatus using other separation and/or other processing means using simple phase separation in a vessel or drum
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2210/00—Processes characterised by the type or other details of the feed stream
    • F25J2210/12—Refinery or petrochemical off-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
    • F25J2230/00—Processes or apparatus involving steps for increasing the pressure of gaseous process streams
    • F25J2230/30—Compression 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
    • F25J2270/04—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
    • F25J2270/12—External refrigeration with liquid vaporising loop

Definitions

  • the present invention relates to a plant and a method for separating in general a feed composition comprising methane and C 2+ -hydrocarbons into a methane depleted fraction as product composition and into a methane enriched fraction as well as specifically to a plant and a method for separating liquified petroleum gas from fuel gas by cryogenic distillation.
  • Refinery fuel gas is generated during the petroleum refinery process and is a gas mixture consisting essentially of short-chain hydrocarbons, namely mainly of methane and smaller amounts of ethane, propane and butane.
  • refinery fuel gas may contain non-hydrocarbons, such as hydrogen, nitrogen, carbon monoxide, carbon dioxide or the like, and small amounts of larger-chain hydrocarbons.
  • refinery fuel gas has been combusted for decades for instance in the refinery plant itself, such as in process heaters, in turbines or the like.
  • Examples for such other applications are for instance the use as raw material for chemical syntheses or in form of liquified petroleum gas (LPG) - which essentially consists of C 3-4 -hydrocarbons and C 2 -hydrocarbons - as cooling agent, as fuel for homes or the like.
  • LPG liquified petroleum gas
  • This separation of a C 2-4 -hydrocarbon-rich fraction or of a C 3-4 -hydrocarbon-rich fraction, respectively, from refinery fuel gas has also environmental benefits. More specifically, methane has a higher upper heating value and leads to lower specific carbon dioxide emissions during combustion compared to the ingredients of C 2-4 -hydrocarbons or liquified petroleum gas, respectively. This is nowadays a particular advantage, since it helps industrial companies to reduce carbon emissions and thus to improve their environmental social and governance scores.
  • the object underlying the present invention is to provide a plant and a method for separating in general a feed composition comprising methane and C 2+ -hydrocarbons into a methane depleted fraction as product composition and into a methane enriched fraction and specifically to provide a plant and a method for separating liquified petroleum gas from fuel gas by cryogenic distillation, which have a reduced energy demand during operation, but nevertheless an excellent separation efficiency.
  • this object is satisfied by providing a plant for separating a feed composition comprising methane and C 2+ -hydrocarbons into a methane depleted fraction as product composition and into a methane enriched fraction, in particular for separating liquified petroleum gas from (refinery) fuel gas, wherein the plant comprises:
  • the condenser the cold expanded gas obtained in the turboexpander as cooling agent, in order to achieve a suitably low temperature at the overheads of the condenser and to thereby obtain a sufficiently high separation of liquefied petroleum gas from the fuel gas.
  • the arrangement of the gas-liquid separator upstream of the turboexpander helps to decrease the energy demand for operating the plant, because the liquid fraction of the methane enriched fraction being condensed in the condensers does not need to be processed in the turboexpander, but only the gas fraction of the methane enriched fraction. This does not exclude that downstream of the turboexpander a further gas-liquid separator is arranged; however, it is important that one gas-liquid separator is arranged upstream of the turboexpander and that the liquid fraction obtained therein is recycled into the distillation column.
  • Separating a feed composition comprising methane and C 2+ -hydrocarbons into a methane depleted fraction as product composition and into a methane enriched fraction means in accordance with the present invention that the methane depleted fraction contains - on a percentage basis - less methane than the feed composition and that the methane enriched fraction contains more methane than the feed composition.
  • the condenser for condensing a portion of the methane enriched fraction so as to produce a mixed-phase effluent comprising a condensed phase and a vapor phase may be connected with the overheads outlet line of the distillation column directly or indirectly.
  • the condenser is indirectly connected with the overheads outlet line of the distillation column.
  • a pre-condenser for condensing a portion of the methane enriched fraction is arranged between the overheads outlet line of the distillation column and the condenser, wherein the pre-condenser is connected with the overheads outlet line of the distillation column and the condenser is connected with the pre-condenser.
  • the present invention is not particularly limited concerning the kind of the pre-condenser.
  • good results are in particular obtained, when the pre-condenser is part of a single-stage vapor compression refrigeration unit. This allows to energy-efficiently cool the methane enriched fraction obtained as overheads fraction of the distillation column.
  • the pre-condenser preferably is part of a single-stage vapor compression refrigeration unit, which comprises two heat exchangers, a throttle and a compressor, wherein one of the two heat exchangers is the pre-condenser.
  • a first of the two heat exchangers being the pre-condenser is connected via a vapor line for the cooling agent (or refrigerant, respectively) with the compressor, which in turn is connected via a vapor line for compressed cooling agent with the second heat exchanger.
  • the second heat exchanger preferably further comprises a liquid outlet line for the condensed cooling agent, which is connected via a line with the throttle, which in turn is connected via a liquid/vapor line with the first heat exchanger or pre-condenser, respectively. While the second heat exchanger functions as condenser for the cooling agent, the first heat exchanger functions as evaporator for the cooling agent and as pre-condensor for the methane enriched fraction.
  • the second heat exchanger which is hotter and releases heat preferably by cooling it with air and/or water, is a condenser and the first heat exchanger or pre-condenser, respectively, which is colder and accepts heat, is an evaporator.
  • the cooling agent enters the compressor as a low pressure and low temperature vapor. Then, the pressure of the vapor is increased and the cooling agent leaves the compressor as a higher temperature and higher pressure superheated gas.
  • This hot pressurized gas of the cooling agent then passes through the second heat exchanger or condenser, respectively, where it releases heat to the surroundings as it cools and condenses completely.
  • the cooler high-pressure liquid of the cooling agent then passes through the throttle or Joules Thomson throttle valve, which is in fact an expansion valve, which reduces the pressure of the cooling agent abruptly and thereby causes that the temperature of the cooling agent drops drastically.
  • the cold low-pressure mixture of liquid and vapor of the cooling agent then travels through the first heat exchanger or pre-condenser, respectively, or evaporator, respectively, where the cooling agent vaporizes completely as it accepts heat from the surroundings before it returns to the compressor as a low pressure low temperature gas to start the cycle again.
  • the methane enriched fraction is led through the first heat exchanger and the first heat exchanger is for the methane enriched fraction the pre-condenser, in which the methane enriched fraction is cooled and thereby partially condensed by the cold low-pressure mixture of liquid and vapor of the cooling agent traveling through the first heat exchanger.
  • the two heat exchangers of the pre-condenser are shell and tube heat exchangers.
  • the cooling agent may be led through the tubes of both heat exchangers or through the shells of both heat exchangers.
  • the cooling agent is led through the tubes of both heat exchangers and the methane enriched fraction is led through the shell of the first heat exchanger.
  • the shell of the second heat exchanger may be cooled by air, water or any other medium.
  • a brazed aluminum heat exchanger as well as cold box may be used for the first heat exchanger, which are more energy efficient, but involve higher costs.
  • the throttle or Joules Thomson throttle valve, respectively, of the single-stage vapor compression refrigeration unit is replaced by an expander.
  • a Joules Thomson throttle valve provides for pressure let down, but does not enable recovery of energy, as with an expander, to reduce operating costs.
  • An expander can be used to partially drive a compressor and can be used to generate electricity.
  • an expander can be designed to be close to constant entropy operation whereas, Joules Thomson throttle valve follows constant enthalpy. The difference in stream enthalpy enables additional cooling across the evaporator for an expander compared to a Joules Thomson throttle valve.
  • the condenser for condensing a portion of the methane enriched fraction is connected with the pre-condenser.
  • the pre-condenser comprises an inlet line for the methane enriched fraction obtained as overheads fraction of the distillation column, wherein the inlet line is connected with the overheads outlet line of the distillation column.
  • the pre-condenser comprises an outlet line for the pre-condensed methane enriched fraction, wherein the outlet line is connected with an inlet line of the condenser.
  • the condenser is called condenser, even if the optional, but preferred, pre-condenser is in fact also a condenser.
  • the condenser is a shell and tube condenser.
  • the methane enriched fraction to be cooled and partially condensed may be led through the tubes and the expanded gas generated in the turboexpander may be led through the shell of the condenser or the methane enriched fraction to be cooled and partially condensed may be led through the shell and the expanded gas generated in the turboexpander may be led through the tubes of the shell and tube condenser.
  • the methane enriched fraction is led through the tubes and the expanded gas generated in the turboexpander is led through the shell of the shell and tube condenser.
  • a brazed aluminum heat exchanger as well as cold box may be used for the condenser, which are more energy efficient, but involve higher costs.
  • the gas-liquid separator for the partially condensed methane enriched fraction is connected with the condenser, which means that the condenser comprises an outlet for the methane enriched fraction having been partially condensed therein and that the gas-liquid separator comprises an inlet line being connected with the outlet line of the condenser for the partially condensed methane enriched fraction having been generated in the condenser.
  • the present invention is not specifically limited concerning the type of gas-liquid separator.
  • the gas-liquid separator may be a drum or any other kind of a gas-liquid settling vessel.
  • the gas-liquid separator may comprise one or more internals supporting the separation of gas and liquid phases, such as an inlet diffusor, a de-entrainment device or the like. While the outlet line for gas of the gas-liquid separator is connected with the turboexpander, the outlet line for liquid of the gas-liquid separator is connected with the distillation column, in order to reflux the condensed portion of the methane enriched fraction into the distillation column.
  • a gas-liquid separator for the partially condensed methane enriched fraction is arranged upstream of the turboexpander (but downstream of the distillation column) and that the condensed fraction of the methane enriched fraction is removed there and refluxed into the distillation column, because this helps to decrease the energy demand for operating the plant.
  • the gas-liquid separator assures that all liquid is removed from the methane enriched fraction entering the turboexpander. This is important, because liquid entering a turboexpander can damage the turboexpander. Distillation columns flood for various reasons at unexpected times and when they flood, the overheads fraction includes liquid.
  • the gas-liquid separator also "buffers" such temporary liquid-carryover of the distillation column in the methane enriched fraction.
  • the outlet line for gas of the gas-liquid separator through which the gas portion of the methane enriched fraction flows is connected with the turboexpander, in which the methane enriched fraction is fast expanded and thereby drastically cooled, before the expanded and cooled methane enriched fraction is led as cooling agent to the condenser.
  • the present invention is not particularly restricted concerning the type of the turboexpander, as long as it allows to fast expand and drastically cools the gaseous methane enriched fraction. Good results are for instance achieved, when the turboexpander design follows closely to constant entropy operation.
  • the distillation column may be any distillation column being suitable for cryogenic distillation.
  • the distillation column preferably comprises at least one internal element selected from the group consisting of trays, structured packings, random packings and arbitrary combinations of two or more of the aforementioned elements.
  • distributors and collectors may be included above and below the one or more internal elements.
  • distillation column is designed to be operated so as to have during the operation 15 to 40 theoretical stages and preferably 20 to 30 theoretical stages.
  • the distillation column does not comprise within the distillation column any cooler and does not comprise within the distillation column any condenser.
  • Such internal coolers and condensers are disadvantageous, because they require costly and difficult maintenance over that of conventional condensing exchangers. Moreover, they are disadvantageous in view of the plant investment costs and the operational costs. Furthermore, such internal coolers and condensers are disadvantageous, because they have an increased distillation column height, if the number of internal stages remain the same, or, if the number of internal stages is reduced so as to maintain the height of the distillation column, then the distillation column with such internal coolers and condensers has a lower separation efficiency.
  • a further disadvantage thereof is that a more complexed internal design is necessary in order to fit in the condensor and additional equipment for liquid collection and redistribution into the distillation column.
  • an important feature of the present invention is that the outlet line for expanded gas of the turboexpander is directly or indirectly connected with the condenser so as to cool the methane enriched fraction within the condenser by using the expanded gas of the turboexpander, which is drastically cooled as consequence of the expansion, as cooling agent.
  • the condenser comprises an inlet line for the expanded gas generated by the turboexpander, wherein this inlet line is directly or indirectly connected with the outlet line for expanded gas of the turboexpander.
  • the outlet line for expanded gas of the turboexpander is directly connected with the condenser, i.e. there is no further unit, element or device arranged between the beginning of the outlet line for expanded gas of the turboexpander and the inlet line for the expanded gas into the condenser.
  • the outlet line for expanded gas of the turboexpander is indirectly connected with the condenser so as to cool the methane enriched fraction within the condenser using the expanded gas as cooling agent, i.e. there is at least one further unit, element or device arranged between the beginning of the outlet line for expanded gas of the turboexpander and the inlet line for the expanded gas into the condenser. It is preferred in this embodiment that the outlet line for expanded gas of the turboexpander is connected with a second gas-liquid separator, which is in turn connected with the condenser. Optional gas-liquid separator(s) upstream of the distillation column are not considered in this numeration.
  • the second gas-liquid separator comprises an inlet line being connected with the outlet line for expanded gas of the turboexpander.
  • the second gas-liquid separator comprises an outlet line for gas and an outlet line for liquid, wherein the outlet line for liquid is connected directly or indirectly with the distillation column so as to reflux the liquid into the distillation column, and wherein the outlet line for gas is connected with the condenser or with an inlet line of the condenser, respectively, so as to cool the methane enriched fraction within the condenser.
  • the gaseous phase of the expanded methane enriched fraction is used as cooling agent in the condenser.
  • the outlet line for liquid is preferably connected directly with the distillation column or into the outlet line for liquid of the upstream, i.e. first gas-liquid separator.
  • the provision of the second gas-liquid separator has the advantage that the C 2 -hydrocarbon content of the product composition is slightly increased, whereas the C 2 -hydrocarbon content of the methane enriched fraction is decreased.
  • the provision of the second gas-liquid separator leads to a small increase of the operational costs.
  • the second gas-liquid separator may be embodied as the above-mentioned (first) gas-liquid separator.
  • the second gas-liquid separator may be a drum or any other kind of a gas-liquid settling vessel and it may comprise one or more internals supporting the separation of gas and liquid phases, such as an inlet diffusor, a de-entrainment device or the like.
  • the plant further comprises upstream of the distillation column one or more coolers and/or one or more heat exchangers and/or one or more compressors and/or one or more other devices, such as a gas-liquid separator, a drying unit or the like.
  • the plant preferably comprises a feed line, which means a line being connected with the inlet line of the distillation column and thus feeding the feed composition into the inlet line, but which is connected - before leading into the inlet line - with at least one of the aforementioned elements, i.e. cooler(s), heat exchanger(s), compressor(s) and other device(s).
  • the feed line is connected with a heat exchanger for cooling the feed
  • the heat exchanger comprises an inlet line for the feed composition, an inlet line being connected with the outlet line for withdrawing the expanded gas from the condenser functioning as cooling agent in the heat exchanger, an outlet line for the cooling agent and an outlet line for the cooled feed, wherein the outlet line for the cooled feed is connected with the inlet line of the distillation column or forms the inlet line of the distillation column, respectively.
  • the cold expanded methane rich fraction being removed from the condenser thus cools the feed composition, before the cold feed composition is led into the distillation column.
  • the operational costs are further decreased.
  • the expanded methane rich fraction as the cooling agent may be led through the tubes and the feed composition through the shell of the heat exchanger, or vice versa.
  • the expanded methane rich fraction as the cooling agent is led through the shell and the feed composition through the tubes of the heat exchanger.
  • a brazed aluminum heat exchanger as well as cold box may be used for the heat exchanger, which are more energy efficient, but involve higher costs.
  • the feed line is connected with a first cooler, which is, if the plant comprises the aforementioned heat exchanger, arranged upstream of the heat exchanger.
  • the first cooler may be any kind of cooler, but it is preferably an air cooler.
  • the first cooler comprises an inlet line being connected with the feed line and an outlet line being connected with the inlet of the heat exchanger for the feed composition, or, if such a heat exchanger is not present, with the inlet line for the feed composition into the distillation column.
  • the feed line is further connected with a second cooler being arranged downstream of the first cooler and upstream of the heat exchanger, if a heat exchanger is present.
  • the second cooler may be any kind of cooler, but it is preferably a water cooler.
  • the second cooler comprises an inlet line (which is a section of the feed line) being connected with the outlet line for feed composition of the first cooler (which is another section of the feed line) and an outlet line (which is a section of the feed line) being connected with the inlet for the feed composition of the heat exchanger, or, if such a heat exchanger is not present, with the inlet line for the feed composition into the distillation column.
  • the distillation column comprises a recirculation line and the plant further comprises a reboiler, wherein the recirculation line is connected with the reboiler and leads from the bottom of the distillation column to a side section of the distillation column.
  • the reboiler is further connected with the feed line (one section of the feed line is the inlet line of the reboiler, whereas another section of the feed line is the outlet line of the reboiler for the feed composition), which is directly or indirectly connected, if at least one cooler is present upstream of the distillation column, with the most upstream thereof, or, if no cooler is present, with the heat exchanger or, if such a heat exchanger is not present, with the inlet line for the feed composition into the distillation column.
  • the reboiler comprises an inlet for bottom fraction being connected with the part of the recirculation line deriving from the bottom of the distillation column and an outlet for bottom fraction being connected with the part of the recirculation line leading to the side section of the distillation column.
  • the reboiler comprises an inlet for feed composition being connected with a section of the feed line and an outlet for feed composition being connected with another section of the feed line arranged downstream thereof and leading, if one or more coolers are present, into the most upstream cooler, or, if no cooler but one or more heat exchangers are present, into the respective inlet of the most upstream heat exchanger, or, if no cooler and no heat exchangers are present, into the inlet line of the distillation column.
  • This embodiment allows to use internal heat of the feed composition to heat the bottom fraction of the distillation column to thereby cool the feed composition and reduce the reboiler heating medium utility cost.
  • the feed line is connected with a gas-liquid separator. Since this gas-liquid separator is located upstream of the distillation column, it is not considered for the numeration (first, second and so on) of the gas-liquid separator(s) being arranged downstream of the distillation column.
  • the gas-liquid separator comprises a section of the feed line as inlet line for the feed composition, an outlet line for liquid and an outlet line for gas, wherein the outlet line for gas is connected with a compressor for compressing the feed composition.
  • the compressor comprises a section of the feed line as outlet line, which is directly or indirectly connected, if a reboiler is present, with the inlet for feed composition of the reboiler, or, of no reboiler is present, with the most upstream cooler, if at least one cooler is present upstream of the distillation column, or, if no cooler is present, with the heat exchanger or, if such a heat exchanger is not present, with the inlet line for the feed composition into the distillation column.
  • the feed line is connected with a pretreatment unit, which preferably comprises a molecular sieve or a dryer.
  • the pretreatment unit comprises a section of the feed line as outlet line, which is directly or indirectly connected with the inlet line for the feed composition of the gas-liquid separator being upstream of the distillation column, or, if such a gas-liquid separator is not present, with the inlet for feed composition of the reboiler, or, of no reboiler is present, with the most upstream cooler, if at least one cooler is present upstream of the distillation column, or, if no cooler is present, with the heat exchanger or, if such a heat exchanger is not present, with the inlet line for the feed composition into the distillation column.
  • the present invention relates to a method for separating a feed composition comprising methane and C 2+ -hydrocarbons into a methane depleted fraction as product composition and into a methane enriched fraction, wherein the method is performed in the aforementioned plant.
  • the method comprises in accordance with a first embodiment the steps of:
  • the method comprises the steps of:
  • the method further comprises the steps of leading the feed composition into and through the heat exchanger being arranged upstream of the distillation column and of further leading the methane enriched fraction withdrawn from the condenser in step vi) into and through the heat exchanger being arranged upstream of the distillation column so as to cool the feed composition by using the methane enriched fraction withdrawn from the condenser in step vi) as cooling agent. Afterwards, the cooled feed composition is fed into the distillation column.
  • the method comprises one or more cooling steps for cooling the feed composition by one or more coolers.
  • the method comprises a first cooling step of cooling the feed composition in a first cooler, which is preferably an air cooler, and a second cooling step of cooling the feed composition in a second cooler, which is arranged downstream of the first cooler and which is preferably a water cooler, before the cooled feed composition is fed into the distillation column or, if the aforementioned heat exchange step is performed, into the aforementioned heat exchanger.
  • the feed composition is subjected to a heat exchange in the reboiler. More specifically, the feed composition is led into and through the reboiler being arranged in the recirculation line so as to cool the feed composition by heat exchange with the bottom fraction of the distillation column being recirculated in the recirculation line. The so treated feed composition is then fed into the distillation column or, if the aforementioned heat exchange step with the expanded methane enriched fraction is performed, into the respective heat exchanger, or if the aforementioned one or more cooling steps are performed, into the most upstream of the one or more coolers.
  • the method comprises the steps of gas-liquid-separating the feed composition and to compress the gaseous portion of the feed composition obtained in the gas-liquid-separating step.
  • the compressed gaseous feed composition is then fed into the distillation column or, if the aforementioned heat exchange step with the expanded methane enriched fraction is performed, into the respective heat exchanger, or if the aforementioned one or more cooling steps are performed, into the most upstream of the one or more coolers, or, if the aforementioned heat exchange step with the recirculated bottom fraction of the distillation column is performed, into the reboiler.
  • the feed stream may be pretreated, for instance by subjecting it to a molecular sieve or by drying it, before the pretreated feed composition is led into any of the aforementioned steps.
  • the feed composition is fuel gas, from which liquified petroleum gas is separated as the methane depleted fraction.
  • the feed composition comprises, based on 100% by weight of the feed composition:
  • feed compositions are, based on 100% by weight of the feed composition:
  • a specific example of a product composition is, based on 100% by weight of the respective product composition:
  • a specific example of a methane enriched fraction is, based on 100% by weight of the respective methane enriched fraction:
  • the distillation is performed as cryogenic distillation.
  • the temperature of the mixture within the gas-liquid separator is between -20 to -60°C and preferably between -30 to -50°C, such as -40°C, and/or the temperature of the mixture within the second gas-liquid separator, if present, is between -60 to -100°C and preferably between -70 to -90°C, such as -80°C.
  • the temperature at the bottom of the distillation column is preferably between 55 and 105°C and preferably between 65 and 85°C.
  • the pressure within the distillation column is 14 to 69 bar and preferably 20 to 35 bar.
  • the distillation column comprises at least one internal element selected from the group consisting of trays, structured packings, random packings and arbitrary combinations of two or more of the aforementioned elements, wherein the distillation column is operated so that it has a height to accommodate 15 to 40 theoretical stages and preferably 20 to 30 theoretical stages.
  • a pre-condenser being part of a single-stage vapor compression refrigeration unit is used, in which propylene, propane or ammonia is used as cooling agent.
  • the methane rich fraction is expanded in the turboexpander by at least the factor 3 to 1, preferably 5 to 1 and more preferably 10 to 1.
  • the plant 10 shown in figure 1 comprises a feed inlet line 12 i , 12 ii , 12 iii , 12 iv , 12 v , 12 vi , 12 vii , 12 viii , which is connected, from the upstream direction to the downstream direction, with a dryer 14, with a gas-liquid separator 16, with a compressor 18, with a reboiler 20, with a first cooler 22 being an air-cooler, with a second cooler 23 being a water cooler, with a heat exchanger 24 and with a distillation column 25.
  • the gas-liquid separator 16 comprises a liquid outlet line 26 and an outlet for gas, which is connected with the feed line section 12 iii .
  • the reboiler 20 is connected with a recirculation line 28, 28 i , the first section 28 of which connecting the bottom of the distillation column 25 with the reboiler and the second portion 28' of which connecting the reboiler with a side section of the distillation column 25.
  • the reboiler 20 is a tube and shell reboiler 20 and the recirculation line sections 28, 28 i are connected with the tubes of the reboiler 20, whereas the feed line sections 12 iv , 12 v are connected with the shell of the reboiler 20.
  • the heat exchanger 24 is a tube and shell heat exchanger 24 and the feed line sections 12 vii , 12 viii are connected with the tubes of the heat exchanger 24.
  • the distillation column 25 comprises an overheads outlet line 30 for the methane enriched fraction obtained in the distillation column 25 as overheads fraction and a bottom outlet line 32 for the methane depleted fraction or product composition, respectively, which is obtained in the distillation column 25 as bottom fraction.
  • the overheads outlet line 30 is connected with a pre-condensor 34 being part of a single-stage vapor compression refrigeration unit 35, wherein the pre-condensor 34 is connected via line 36 with the condenser 38.
  • the condenser 38 is a tube and shell condenser, wherein the line 36 leading the methane enriched fraction into the condenser 38 is connected with the shell of the condenser 38.
  • the condenser 38 is also connected with a line 40 being connected with the shell of the condenser 38 for withdrawing the methane enriched fraction from the condenser 38.
  • the line 40 is connected with the gas-liquid separator 42, which comprises an outlet line for gas 44 and an outlet line for liquid 46. While the outlet line for liquid 46 is connected with the distillation column 25 and is in fact a reflux line, the outlet line for gas 44 of the condenser 38 is connected with the turboexpander 48.
  • the turboexpander 48 comprises an outlet line 50 for expanded gas, which is connected with the condenser 38 so as to cool the methane enriched fraction within the condenser 38.
  • the condenser 38 further comprises an outlet line 52 for withdrawing the expanded gas from the condenser 38, which is connected with the heat exchanger 24.
  • Heat exchanger 24 further comprises an outlet line 54 for the methane enriched fraction.
  • the single-stage vapor compression refrigeration unit 35 comprises a first heat exchanger being the pre-condensor 34, a second heat exchanger 62, a throttle 64 and a compressor 66.
  • the first heat exchanger or pre-condensor 34 respectively, is connected via a vapor line 68 for the cooling agent with the compressor 66, which in turn is connected via a vapor line 70 for compressed cooling agent with the second heat exchanger 62.
  • the second heat exchanger 62 further comprises a liquid outlet line 72 for the condensed cooling agent, which is connected with the throttle 64, which in turn is connected via a liquid/vapor line 74 with the first heat exchanger or pre-condensor 34, respectively.
  • the second heat exchanger 62 functions as condenser for the cooling agent
  • the first heat exchanger or pre-condensor 34 respectively functions as evaporator for the cooling agent and as pre-condensor for the methane enriched fraction.
  • the second heat exchanger 62 which is hotter and releases heat preferably by cooling it with air and/or water, is a condenser and the first heat exchanger or pre-condensor 34, respectively, which is colder and accepts heat, is an evaporator.
  • the cooling agent enters the compressor 66 as a low pressure and low temperature vapor.
  • the pressure of the vapor is increased and the cooling agent 66 leaves the compressor as a higher temperature and higher pressure superheated gas.
  • This hot pressurized gas of the cooling agent then passes through the second heat exchanger 62, where it releases heat to the surroundings as it cools and condenses completely.
  • the cooler high-pressure liquid of the cooling agent then passes through the throttle 64, which is in fact an expansion valve, which reduces the pressure of the cooling agent abruptly and thereby causes that the temperature of the cooling agent drops drastically.
  • the cold low-pressure mixture of liquid and vapor of the cooling agent then travels through the first heat exchanger or pre-condensor 34, respectively, or evaporator, respectively, where the cooling agent vaporizes completely as it accepts heat from the surroundings before it returns to the compressor as a low pressure low temperature gas to start the cycle again.
  • the methane enriched fraction is cooled and thereby partially condensed in the pre-condensor 34 by the cold low-pressure mixture of liquid and vapor of the cooling agent traveling therethrough.
  • the feed composition is dried in the dryer, before the dried feed composition is subjected in the gas-liquid separator to a gas-liquid separation. While the liquid fraction of the feed composition is withdrawn from the plant, the gas fraction of the feed composition is compressed in the compressor 18 and then cooled in the reboiler 20, in the first cooler 22, in the second cooler 23 and in the heat exchanger 24, before the cold feed composition is fed into the distillation column. During the distillation, a bottom fraction of methane depleted fraction, which is the product composition or liquefied petroleum gas, respectively, is withdrawn via the bottom outlet line 32 from the distillation column 25 and from the plant 10.
  • a methane enriched fraction is withdrawn from the distillation column via the overheads outlet line 30 and is cooled and partially condensed in the pre-condensor 34 and in the condenser 38, before the so treated methane enriched fraction is separated in the gas-liquid separator 42 into a liquid methane enriched fraction and into a gaseous methane enriched fraction.
  • the liquid methane enriched fraction is withdrawn from the gas-liquid separator 42 the outlet line 46 and refluxed into the distillation column, the gaseous methane enriched fraction is expanded and thereby cooled in the turboexpander 48.
  • the expanded and cooled methane enriched fraction is led as cooling agent through the condensor as well as through the heat exchanger 28, before the methane enriched fraction is withdrawn via the outlet line 54 from the plant 10.
  • the plant 10 shown in figure 3 corresponds to that of figure 1 , except that the outlet line 50 of the turboexpander 48 does not directly lead into the condenser 38, but is first led to a second gas-liquid separator 56 being arranged downstream of the distillation column 25, in which the expanded and cooled methane enriched fraction generated in the turboexpander 48 is separated into a liquid fraction and into a gaseous fraction. While the liquid fraction is withdrawn from the second gas-liquid separator 56 via the outlet line 58 and refluxed into the distillation column, the gaseous fraction is led as cooling agent via line 60 into the condenser 38 and via line 52 into the heat exchanger 24, before the methane enriched fraction is withdrawn from the plant via the outlet line 54.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Separation By Low-Temperature Treatments (AREA)
EP22198757.1A 2022-09-29 2022-09-29 Anlage und verfahren zur abtrennung von flüssiggas aus brenngas durch kryogene destillation Pending EP4345406A1 (de)

Priority Applications (2)

Application Number Priority Date Filing Date Title
EP22198757.1A EP4345406A1 (de) 2022-09-29 2022-09-29 Anlage und verfahren zur abtrennung von flüssiggas aus brenngas durch kryogene destillation
PCT/EP2023/074787 WO2024068241A1 (en) 2022-09-29 2023-09-08 Plant and method for separating liquified petroleum gas from fuel gas by cryogenic distillation

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP22198757.1A EP4345406A1 (de) 2022-09-29 2022-09-29 Anlage und verfahren zur abtrennung von flüssiggas aus brenngas durch kryogene destillation

Publications (1)

Publication Number Publication Date
EP4345406A1 true EP4345406A1 (de) 2024-04-03

Family

ID=83508487

Family Applications (1)

Application Number Title Priority Date Filing Date
EP22198757.1A Pending EP4345406A1 (de) 2022-09-29 2022-09-29 Anlage und verfahren zur abtrennung von flüssiggas aus brenngas durch kryogene destillation

Country Status (2)

Country Link
EP (1) EP4345406A1 (de)
WO (1) WO2024068241A1 (de)

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2601009A (en) * 1949-12-01 1952-06-17 Inst Of Inventive Res Method of low-temperature separation of gases into constituents
US4163652A (en) * 1976-03-26 1979-08-07 Snamprogetti S.P.A. Refrigerative fractionation of cracking-gases in ethylene production plants
US5960644A (en) * 1996-06-05 1999-10-05 Shell Oil Company Removing carbon dioxide, ethane and heavier components from a natural gas
CN106839650A (zh) * 2017-03-21 2017-06-13 四川华亿石油天然气工程有限公司 天然气油气回收系统及工艺
US20180274854A1 (en) * 2015-12-18 2018-09-27 Bechtel Hydrocarbon Technology Solution, Inc. Systems and Methods for Recovering Desired Light Hydrocarbons from Refinery Waste Gas Using a Back-End Turboexpander
US20200032677A1 (en) * 2017-08-08 2020-01-30 Saudi Arabian Oil Company Natural gas liquid fractionation plant waste heat conversion to potable water using modified multi-effect distillation system
DE102019115407A1 (de) * 2019-06-06 2020-12-10 Linde Gmbh Verfahren und Anlage zur Gewinnung eines oder mehrerer Olefine
DE102019115388A1 (de) * 2019-06-06 2020-12-10 Linde Gmbh Verfahren und Anlage zur Gewinnung eines Olefins

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2552451A (en) * 1947-07-03 1951-05-08 Standard Oil Dev Co Fractionation of low molecular weight component mixtures
US2775103A (en) * 1954-12-23 1956-12-25 Phillips Petroleum Co Hydrocarbon separation

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2601009A (en) * 1949-12-01 1952-06-17 Inst Of Inventive Res Method of low-temperature separation of gases into constituents
US4163652A (en) * 1976-03-26 1979-08-07 Snamprogetti S.P.A. Refrigerative fractionation of cracking-gases in ethylene production plants
US5960644A (en) * 1996-06-05 1999-10-05 Shell Oil Company Removing carbon dioxide, ethane and heavier components from a natural gas
US20180274854A1 (en) * 2015-12-18 2018-09-27 Bechtel Hydrocarbon Technology Solution, Inc. Systems and Methods for Recovering Desired Light Hydrocarbons from Refinery Waste Gas Using a Back-End Turboexpander
CN106839650A (zh) * 2017-03-21 2017-06-13 四川华亿石油天然气工程有限公司 天然气油气回收系统及工艺
US20200032677A1 (en) * 2017-08-08 2020-01-30 Saudi Arabian Oil Company Natural gas liquid fractionation plant waste heat conversion to potable water using modified multi-effect distillation system
DE102019115407A1 (de) * 2019-06-06 2020-12-10 Linde Gmbh Verfahren und Anlage zur Gewinnung eines oder mehrerer Olefine
DE102019115388A1 (de) * 2019-06-06 2020-12-10 Linde Gmbh Verfahren und Anlage zur Gewinnung eines Olefins

Also Published As

Publication number Publication date
WO2024068241A1 (en) 2024-04-04

Similar Documents

Publication Publication Date Title
RU2355960C1 (ru) Двухступенчатый отвод азота из сжиженного природного газа
US3205669A (en) Recovery of natural gas liquids, helium concentrate, and pure nitrogen
RU2362954C2 (ru) Очистка сжиженного природного газа
CN101108977B (zh) 在液化天然气制备中的一体化ngl回收
RU2668303C1 (ru) Система и способ для сжижения природного газа (варианты)
US5275005A (en) Gas processing
US7257966B2 (en) Internal refrigeration for enhanced NGL recovery
US4203742A (en) Process for the recovery of ethane and heavier hydrocarbon components from methane-rich gases
CN100592013C (zh) 利用从液化天然气中提取的冷量生产液氧的空气分离方法
US20140083132A1 (en) Process for liquefaction of natural gas
AU701090B2 (en) Method and installation for the liquefaction of natural gas
EA011919B1 (ru) Сжижение природного газа
CA1245546A (en) Separation of hydrocarbon mixtures
SA110310707B1 (ar) معالجة غاز هيدروكربونى
CN1296669C (zh) 氮气排除方法
JPH06101963A (ja) 空気の高圧低温蒸留方法
JPH06117753A (ja) 空気の高圧低温蒸留方法
US4608068A (en) Recovery of C3+ hydrocarbons
EA010538B1 (ru) Сжижение природного газа
CN112179048B (zh) 一种贫氦天然气轻烃回收与提氦的联产系统和方法
RU2317497C2 (ru) Способ сжижения богатого углеводородами потока с одновременным извлечением c3+-богатой фракции с высоким выходом
US4158556A (en) Nitrogen-methane separation process and system
CN102906232A (zh) 来自烃类热裂解设备的裂化气流的处理方法和相关设备
US3203193A (en) Production of nitrogen
NO310163B1 (no) Fremgangsmåte og apparat for kondensering av hydrogen

Legal Events

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

Free format text: ORIGINAL CODE: 0009012

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

Free format text: STATUS: THE APPLICATION HAS BEEN PUBLISHED

AK Designated contracting states

Kind code of ref document: A1

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