CA2710776A1 - Process and apparatus for the separation of light-boiling components from hydrocarbon mixtures - Google Patents

Process and apparatus for the separation of light-boiling components from hydrocarbon mixtures Download PDF

Info

Publication number
CA2710776A1
CA2710776A1 CA2710776A CA2710776A CA2710776A1 CA 2710776 A1 CA2710776 A1 CA 2710776A1 CA 2710776 A CA2710776 A CA 2710776A CA 2710776 A CA2710776 A CA 2710776A CA 2710776 A1 CA2710776 A1 CA 2710776A1
Authority
CA
Canada
Prior art keywords
condensation
temperature level
boiling fraction
process according
outlet means
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.)
Abandoned
Application number
CA2710776A
Other languages
French (fr)
Inventor
Johannes Menzel
Sascha Wenzel
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.)
ThyssenKrupp Industrial Solutions AG
Original Assignee
Uhde Gmbh
Johannes Menzel
Sascha Wenzel
Thyssenkrupp Uhde Gmbh
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 Uhde Gmbh, Johannes Menzel, Sascha Wenzel, Thyssenkrupp Uhde Gmbh filed Critical Uhde Gmbh
Publication of CA2710776A1 publication Critical patent/CA2710776A1/en
Abandoned legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D3/00—Distillation or related exchange processes in which liquids are contacted with gaseous media, e.g. stripping
    • 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
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C7/00—Purification; Separation; Use of additives
    • C07C7/09—Purification; Separation; Use of additives by fractional condensation
    • 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
    • F25J3/0233—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream characterised by the separated product stream separation of CnHm with 1 carbon atom or more
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
    • F25J3/0228—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream characterised by the separated product stream
    • F25J3/0238—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
    • F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
    • F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
    • F25J3/0228—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream characterised by the separated product stream
    • F25J3/0252—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream characterised by the separated product stream separation of hydrogen
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • 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
    • F25J2200/50—Processes or apparatus using separation by rectification using multiple (re-)boiler-condensers at different heights of the column
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2200/00—Processes or apparatus using separation by rectification
    • F25J2200/74—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
    • F25J2215/00—Processes characterised by the type or other details of the product stream
    • F25J2215/62—Ethane or ethylene
    • 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
    • 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
    • F25J2270/60—Closed external refrigeration cycle with single component refrigerant [SCR], e.g. C1-, C2- or C3-hydrocarbons
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2270/00—Refrigeration techniques used
    • F25J2270/90—External refrigeration, e.g. conventional closed-loop mechanical refrigeration unit using Freon or NH3, unspecified external refrigeration
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
    • F25J2290/00—Other details not covered by groups F25J2200/00 - F25J2280/00
    • F25J2290/40—Vertical layout or arrangement of cold equipments within in the cold box, e.g. columns, condensers, heat exchangers etc.

Abstract

Process and apparatus for the separation of a feed mixture into a higher-boiling and a lower boiling fraction in a continuously operated distillation apparatus comprising at least one inlet pipe for feeding one or more feed mixtures, an outlet means for the lower-boiling fraction, an outlet means for the higher-boiling fraction and a heating device, in which the distillation apparatus includes at least two condensation stages, each of a different temperature level, the condensation stages provided upstream in direction of the vapour flow having a higher temperature level than the downstream condensation stages, separation-effective internals being installed between the condensation stages, partial condensation taking place in the condensation stages, partial amounts that have not condensed in these stages being fed to downstream separation-effective internals or condensation stages of lower temperature level and partial amounts that have condensed being passed via separation-effective internals in direction of the outlet means for the higher-boiling fraction, a basically vaporous fluid being obtained at the condensation stage of the lowest temperature level, where it partially condenses, the uncondensed part of the fluid being fed to the outlet means for the lower--boiling fraction and the condensed part being passed to a section of the distillation apparatus which is upstream of the condensation stage having the lowest temperature level, and the condensation stage of the lowest temperature level having a temperature of below -40 °C.

Description

Process and apparatus for the separation of light-boiling components from hydrocarbon mixtures [0001] The invention relates to a process and an apparatus for the separation of light-boiling components from a hydrocarbon stream, particularly for the separation of a C2 fraction from a C3+ fraction to be obtained as target product, e.g. in the dehydrogenation of light hydrocarbons, but also suitable for other separation tasks within the range of C, to C4-[0002] Usually, such separations are performed by means of a so-called "coldbox" in combination with a distillation column. The distillation column is referred to and operated as a de-ethanizer because all substances of boiling points less or equal to that of ethane are separated overhead by this de-ethanizer.
[0003] Before entering the coldbox, the feed mixture is cooled down to approx.
-25 C.
The condensate gained is passed directly into the de-ethanizer. Vapours that have not condensed are further cooled to approx. -90 C in the coldbox, the product-enriched condensate thus obtained also being directed to the de-ethanizer after heat exchange. The coldbox therefore performs a one-step rough separation.
[0004] The remaining vapour phase basically comprising uncondensable components, e.g. hydrogen, is depressurised after heat exchange in the flow entering the coldbox. The light-boiling substances cool down to approx. -110 C due to the Joule-Thompson effect. This temperature level is used to partially condense the stream entering the coldbox. The uncondensed light-boiling substances are basically free from C3+ components.
[0005] Finally all product-enriched condensate phases are led to a final separation in the de-ethanizer where the remaining light-boiling components are separated form the heavier boiling components. For this purpose a temperature of about -20 C is necessary at the head of the column.
[0006] Evaporating propane or propene can be used at -30 C as a cooling agent for cooling the feed mixture before it enters the coldbox, for operating the coldbox and for cooling the de-ethanizer.
[0007] The generation of cold for such a process is extremely expensive. The aim of the invention is, therefore, to provide a process and an apparatus by which the consumption of cold can be reduced to a significant degree.
[0008] The aim of the invention is achieved according to the main claim by a process for the separation of a feed mixture = into a higher-boiling and a lower boiling fraction in a continuously operated distillation apparatus comprising at least one inlet pipe for feeding one or more feed mixtures, an outlet means for the lower-boiling fraction, an outlet means for the higher-boiling fraction and a heating device, in which = the distillation apparatus includes at least two condensation stages, each of a different temperature level, = the condensation stages provided upstream in direction of the vapour flow having a higher temperature level than the downstream condensation stages, = separation-effective internals are installed between the condensation stages, = partial condensation takes place in the condensation stages, = partial amounts that have not condensed in these stages are fed to downstream separation-effective internals or condensation stages of lower temperature level and partial amounts that have condensed are passed via separation-effective internals in direction of the outlet means for the higher-boiling fraction, = a basically vaporous fluid is obtained at the condensation stage of the lowest temperature level, where it partially condenses, = the uncondensed part of the fluid being recycled to the outlet means for the lower-boiling fraction and the condensed part being recycled to a section of the distillation apparatus which is upstream of the condensation stage having the lowest temperature level, = and the condensation stage of the lowest temperature level having a temperature of below -40 C.
[0009] In embodiments of the invention, the distillation apparatus comprises three to five successive condensation stages, each of a different temperature level.
[0010] In a further embodiment of the invention the condensation stage of the lowest temperature level is operated at a temperature between -120 C and -70 C and a pressure of at least 2 MPa absolute, preferably at least 3 MPa.
[0011] In a further embodiment of the invention the mixture which leaves the distillation apparatus as lower-boiling fraction is depressurised, the mixture thereby cooling down further under exploitation of the Joule-Thompson-effect, and thus being used to cool the condensation stage with the lowest temperature level.
[0012] In a further embodiment of the invention the depressurisation is performed by an expansion turbine.
[0013] Further embodiments of the invention relate to the use of suitable feed mixtures which are of particular advantage to the process for the purpose of obtaining useful products.
[0014] In a further embodiment of the invention the process is used for feed mixtures basically containing hydrogen, hydrocarbons of up to two carbon atoms and hydrocarbons of at least three carbon atoms. At the outlet means for the lower-boiling fraction a mixture is obtained which basically contains hydrogen and hydrocarbons of up to two carbon atoms and basically no hydrocarbons of at least three carbon atoms. At the outlet means for the higher-boiling fraction a mixture is obtained, which basically contains hydrocarbons of at least three carbon atoms and basically neither hydrogen nor hydrocarbons of up to two carbon atoms.
[0015] In a further embodiment of the invention the process is used for feed mixtures containing less than 2 mol-% each of carbon dioxide and water or water vapour.
[0016] In a further embodiment of the invention the feed mixture used is a reaction mixture from the catalytic dehydrogenation of hydrocarbons.
[0017] In a further embodiment of the invention the segment of the distillation apparatus, through which that part of the feed mixture that has condensed in the condensation stage of the highest temperature level is passed to the outlet means for the higher-boiling fraction, is provided as a stripping section of the distillation apparatus.
[0018] In further embodiments of the invention feed mixtures of a relatively small content of components of low boiling point are preferably fed at a point below the condensation stage of the highest temperature level and feed mixtures of a relatively high content of components of low boiling point are preferably fed at a point above the condensation stage of the highest temperature level.
[0019] In a further embodiment of the invention the condensation stages are provided in the form of condensers.
[0020] In a further embodiment of the invention the condensation stages are cooled by cooling water, evaporating ammonia, propane, propene and/or by exploitation of the Joule-Thompson effect when depressurising process gases.
[0021] In a further embodiment of the invention the heating device is operated by external waste heat.
[0022] The invention achieves the aim also by a distillation apparatus suitable for the separation of a feed mixture, comprising:
= one or more inlet pipes for feeding one or more feed mixtures, = an outlet means for the lower-boiling fraction, = an outlet means for the higher-boiling fraction, = at least one heating device, = at least two successive condensers, and = separation-effective internals installed between the condensers.
[0023] In alternative inventive embodiments of the distillation apparatus the latter consists of one single distillation column or consists of a cascade of several distillation columns in which condensers are installed between the distillation columns. In particular it may be provided that the distillation apparatus comprises 3, 4 or 5 successive condensers, each being operated at a different temperature level.
[0024] What was achieved in two process steps in the past, can now be implemented in one single process step according to the invention, without providing an upstream coldbox, which is an advantage of the invention.
[0025] By the use of the distillation apparatus according to the process involving several condensers operating at different temperature levels it is achieved that it is not required to provide the total amount of cooling fluid for the condensation at the lowest temperature level and therefore at the highest costs. Instead, the intermediate condensers are operated at temperature levels of approx. +45 C, +15 C and -30 C, respectively, which is a further advantage of the invention.
[0026] The main part of the rising vapours in the column, if used, therefore condenses before entering the column head condenser and flows downwards as liquid. The coldness level necessary for operating the column head condenser, about -80 C, and the related condensation performance can be produced by depressurising the high-boiling substances within the apparatus itself, which is a further advantage of the invention.
[0027] In the following the invention is illustrated in detail by means of three examples:
Fig. 1 shows an embodiment of the inventive process, in which the distillation apparatus consists of one single distillation column and several intermediate condensers;
Fig. 2 shows an embodiment of the inventive process, in which the distillation apparatus comprises a stripping section and a rectifying section separately of each other;
Fig. 3 shows an embodiment of the inventive process, in which the distillation apparatus comprises three sections with intermediate condensers between these sections.
[0028] In all three examples, vaporous feed mixture 1 can be cooled down first to 15 C
in an ammonia vaporiser 2, for example. In another heat exchanger 3 the obtained C2 fraction 4 is cooled down further to about 10 C, making part of the vapour condense. Vapour phase 5 and condensate 6 are fed separately into the distillation apparatus.
Depending on the composition of the feed mixture the inlet can also be above the condensation stage of the highest temperature level.
[0029] In the example shown in E4,1 the liquid flows downwards in distillation column 7 and is partly evaporated again. The non-evaporated part is drawn-off as a C3+
product 8 at the bottom of distillation column 7. The light-boiling substances rise upward as vapour and partly condense in first condenser 9, which is designed as a two-piece condenser located above the feed tray, cooling water and ammonia being used one after the other as cooling agents. Further rising vapours are partly liquefied in second condenser 10, which is operated with propane or propene as cooling agent so that only a small part of the vapours arrives at head condenser 11. The vapours not condensed in head condenser 11 constitute the C2 fractions 12 and 13 which are depressurised after the condensation in expander 14, hereby cooling down to about -125 C. This cooled vapour 15 is used as cooling agent for the cold side of head condenser 11, where it heats up to about -50 C. Subsequently C2 fraction 4 is conveyed through heat exchanger 3 for cooling feed mixture 1.
[0030] In the example shown in Fig. 2 the liquid flows downwards in stripping column 16 and is partly evaporated again. The non-evaporated part is drawn-off as a C3+
product 8 at the bottom of stripping column 16. The vaporous light-boiling substances 17 flow into first condenser 9, which is designed as a two-piece condenser, where they partly condense, cooling water and ammonia being used as cooling agents one after the other.
Condensate 18 and vapours 19 are given into rectification column 20. Part of the bottom product of rectification column 20 is used as reflux 21 for stripping column 16. Further rising vapours are liquefied in part in second condenser 10, which is operated with propane as cooling agent so that only a small part of the vapours arrives at head condenser 11. Vapours not being condensed in head condenser 11 constitute the C2 fractions 12 and 13 which are depressurised after the condensation in expander 14, hereby cooling down to about -125 C.
This cooled vapour 15 is used as cooling agent for the cold side of head condenser 11, where it heats up to about -50 C. Subsequently this C2 fraction 4 is conveyed through heat exchanger 3 for cooling feed mixture 1.
[0031] In the example shown in Fig. 3 the liquid flows downwards in stripping column 16 and is partly evaporated again. The non-evaporated part is drawn-off as a C3+
product 8 at the bottom of stripping column 16. Vaporous light-boiling substances 17 flow to first condenser 9, which is designed as a two-piece condenser, where they partly condense, cooling water and ammonia being used one after the other as cooling agents.
Condensate 18 and vapours 19 are given into first rectification column 22.
Part of the bottom product of first rectification column 22 is used as reflux for stripping column 16. Further rising vapours are liquefied in part in second condenser 10, which is operated with propane or propene as cooling agent, condensate and vapours are led into second rectification column 23. The bottom product of the second rectification column 23 serves as reflux for the first rectification column 22, in this way only a small part of the vapours arrives at head condenser 11. Vapours not having condensed in head condenser 11 constitute C2 fractions 12 and 13 which are depressurised after the condensation in expander 14, hereby cooling down to about -125 C. This cooled vapour 15 is used as cooling agent for the cold side of head condenser 11, where it heats up to about -50 C. Subsequently this C2 fraction 4 is conveyed through heat exchanger 3 for cooling feed mixture 1.
[0032] In contrast to the preceding variants, this last variant involves the advantage that only the upper part of the second rectification column must be of a design resistant against low temperature and insulated more strongly against heat transfer, which is one of the advantages of the invention.
[0033] In all three examples the heat amount necessary for the operation of the vaporisers exceeds those of the state of the art, but this heat is to be provided at only about 75 C, which is why usually waste heat from other process sections of a plant complex are used which would otherwise have to be removed expensively by means of air coolers, which is another advantage of the invention. In total, a higher refrigerating capacity will be required but the heat can be removed at a less expensive cooling level, which is another advantage of the invention.
[0034] Further advantages of the process of the invention in comparison to the processes mentioned at the beginning are:
By using cooling water, about 25 % of the ammonia refrigeration capacity can be saved, so that a smaller ammonia refrigeration unit is necessary.
The propane refrigeration capacity is about 55 % less so that the compressor capacity for the propane refrigeration circuit is about 50 % less and the compressor can be of a correspondingly smaller size.

Claims (14)

1 claims 1. Process for the separation of a feed mixture obtained from the catalytic dehydrogenation of hydrocarbons, which contains less than 2 mol-% each of carbon dioxide and water or water vapour, into a higher-boiling and a lower-boiling fraction in a continuously operated distillation apparatus comprising at least one inlet pipe for feeding one or more feed mixtures, an outlet means for the lower boiling fraction, an outlet means for the higher boiling fraction and a heating device, characterised in that .cndot. the distillation apparatus includes at least two condensation stages, each of a different temperature level, .cndot. the condensation stages provided upstream in direction of the vapour flow having a higher temperature level than the downstream condensation stages, .cndot. separation-effective internals are installed between the condensation stages, .cndot. partial condensation takes place in the condensation stages, .cndot. partial amounts that have not condensed in these stages are fed to downstream separation-effective internals or condensation stages of lower temperature level and partial amounts that have condensed are passed via separation-effective internals in direction of the outlet means for the higher-boiling fraction, .cndot. a basically vaporous fluid is obtained at the condensation stage of the lowest temperature level, where it partially condenses, .cndot. the uncondensed part of the fluid being fed to the outlet means for the lower-boiling fraction and the condensed part being passed to a section of the distillation apparatus which is upstream of the condensation stage having the lowest temperature level, .cndot. and the condensation stage of the lowest temperature level having a temperature of below -40 °C.
2. Process according to claim 1, characterised in that the distillation apparatus comprises three to five successive condensation stages, each having a different temperature level.
3. Process according to claim 1 or 2, characterised in that the condensation stage of the lowest temperature level is operated at a temperature between -120 °C and -70 °C and a pressure of at least 2 MPa absolute.
4. Process according to claim 3, characterised in that the condensation stage of the lowest temperature level is operated at a temperature between -120 °C
and -70 °C
and a pressure of at least 3 MPa absolute.
5. Process according to any of the claims 1 to 4, characterised in that the mixture which leaves the distillation system as lower boiling fraction is depressurised, the mixture thereby cooling down by exploitation of the Joule-Thompson effect and thus being used to cool the condensation stage of the lowest temperature level.
6. Process according to claim 5, characterised in that the depressurisation is performed by an expansion turbine.
7. Process according to any of the claims 1 to 6, characterized in that a mixture is used as feed mixture which basically consists of hydrogen, hydrocarbons of up to two carbon atoms and hydrocarbons of at least three carbon atoms. At the outlet means for the lower-boiling fraction a mixture is obtained which contains hydrogen and hydrocarbons of up to two carbon atoms and basically no hydrocarbons of at least three carbon atoms. At the outlet means for the higher-boiling fraction a mixture is obtained which contains hydrocarbons of at least three carbon atoms and basically neither hydrogen nor hydrocarbons of up to two carbon atoms.
8. Process according to any of the claims 1 to 7, characterised in that the segment of the distillation apparatus, via which that part of the feed mixture condensed in the condensation stage of the highest temperature level is passed to the outlet means for the higher-boiling fraction, is provided as a stripping section of the distillation apparatus.
9. Process according to any of the claims 1 to 8, characterised in that feed mixtures of a small content of components of low boiling point are preferably fed at a point below the condensation stage of the highest temperature level.
10. Process according to any of the claims 1 to 9, characterised in that feed mixtures of a high content of components of low boiling point are preferably fed at a point above the condensation stage of the highest temperature level.
11. Process according to any of the claims 1 to 10, characterised in that the condensation stages are provided in the form of condensers.
12. Process according to any of the claims 1 to 11, characterised in that the condensation stages
13. Process according to any of the claims 1 to 12, characterised in that one or more heating devices are operated by external waste heat.
14. Distillation apparatus to operate a process according to any of the claims 1 to 13, comprising a) one or more inlet pipes for feeding one or more feed mixtures, b) an outlet means for the lower-boiling fraction, c) an outlet means for the higher-boiling fraction, d) at least one heating device, e) at least two successive condensers, and f) separation-effective internals installed between the condensers, characterised in that the distillation apparatus consists of a cascade of a several distillation columns, in which condensers are provided between the distillation columns.
CA2710776A 2007-12-28 2008-12-22 Process and apparatus for the separation of light-boiling components from hydrocarbon mixtures Abandoned CA2710776A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE102007063347.7 2007-12-28
DE102007063347A DE102007063347A1 (en) 2007-12-28 2007-12-28 Process for the separation of low-boiling components from a hydrocarbon stream
PCT/EP2008/011049 WO2009083227A2 (en) 2007-12-28 2008-12-22 Method and device for separating off low-boiling components from hydrocarbon mixtures

Publications (1)

Publication Number Publication Date
CA2710776A1 true CA2710776A1 (en) 2009-07-09

Family

ID=40690838

Family Applications (1)

Application Number Title Priority Date Filing Date
CA2710776A Abandoned CA2710776A1 (en) 2007-12-28 2008-12-22 Process and apparatus for the separation of light-boiling components from hydrocarbon mixtures

Country Status (12)

Country Link
US (1) US20110041550A1 (en)
EP (1) EP2225007A2 (en)
JP (1) JP2011508031A (en)
KR (1) KR20100125228A (en)
CN (1) CN101932368A (en)
BR (1) BRPI0821955A2 (en)
CA (1) CA2710776A1 (en)
DE (1) DE102007063347A1 (en)
EA (1) EA201070803A1 (en)
MX (1) MX2010007195A (en)
WO (1) WO2009083227A2 (en)
ZA (1) ZA201004516B (en)

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2969746B1 (en) * 2010-12-23 2014-12-05 Air Liquide CONDENSING A FIRST FLUID USING A SECOND FLUID
US10852060B2 (en) * 2011-04-08 2020-12-01 Pilot Energy Solutions, Llc Single-unit gas separation process having expanded, post-separation vent stream
CN108883342A (en) * 2015-12-18 2018-11-23 贝克特尔碳氢技术解决方案股份有限公司 System and method for using rear end turbo-expander to recycle desired light hydrocarbon from refinery flares
WO2018037330A1 (en) * 2016-08-25 2018-03-01 Sabic Global Technologies B.V. Above cryogenic separation process for propane dehydrogenation reactor effluent
CN109722267A (en) * 2017-10-31 2019-05-07 珠海市启夏能源科技有限公司 A kind of tower tank combined type condensate gasification system and its production technology
CN111545086B (en) * 2020-05-27 2021-11-09 新疆大学 Reversible switch type foam system and preparation method thereof
FR3123971B1 (en) * 2021-06-09 2023-04-28 Air Liquide Cryogenic purification of biogas with withdrawal at an intermediate stage and external solidification of carbon dioxide.
FR3123973B1 (en) 2021-06-09 2023-04-28 Air Liquide Cryogenic purification of biogas with pre-separation and external solidification of carbon dioxide
FR3123968B1 (en) * 2021-06-09 2023-04-28 Air Liquide Process for the separation and liquefaction of methane and CO2 comprising the withdrawal of steam from an intermediate stage of the distillation column

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3444696A (en) * 1967-02-10 1969-05-20 Stone & Webster Eng Corp Demethanization employing different temperature level refrigerants
IT1058546B (en) * 1976-03-26 1982-05-10 Snam Progetti PROCESS FOR CRACKING BY CRACKING GAS REFRIGERATION IN ETHYLENE PRODUCTION PLANTS
GB2205933A (en) * 1987-06-12 1988-12-21 Costain Petrocarbon Separation of hydrocarbon mixtures
IT1241471B (en) * 1990-07-06 1994-01-17 Tpl PROCESS AND EQUIPMENT FOR THE MAXIMUM RECOVERY OF ETHYLENE AND PROPYLENE FROM THE GAS PRODUCED BY HYDROCARBON PYROLYSIS.
US5361589A (en) * 1994-02-04 1994-11-08 Air Products And Chemicals, Inc. Precooling for ethylene recovery in dual demethanizer fractionation systems
US6560989B1 (en) * 2002-06-07 2003-05-13 Air Products And Chemicals, Inc. Separation of hydrogen-hydrocarbon gas mixtures using closed-loop gas expander refrigeration
US20070062216A1 (en) * 2003-08-13 2007-03-22 John Mak Liquefied natural gas regasification configuration and method

Also Published As

Publication number Publication date
BRPI0821955A2 (en) 2015-06-23
WO2009083227A3 (en) 2009-09-17
EA201070803A1 (en) 2011-02-28
US20110041550A1 (en) 2011-02-24
WO2009083227A9 (en) 2009-11-05
CN101932368A (en) 2010-12-29
KR20100125228A (en) 2010-11-30
EP2225007A2 (en) 2010-09-08
JP2011508031A (en) 2011-03-10
ZA201004516B (en) 2011-03-30
DE102007063347A1 (en) 2009-07-02
MX2010007195A (en) 2010-09-30
WO2009083227A2 (en) 2009-07-09

Similar Documents

Publication Publication Date Title
US20110041550A1 (en) Process and apparatus for the separation of light-boiling components from hydrocarbon mixtures
CA1337820C (en) Process for c _recovery
US20060218968A1 (en) High propane recovery process and configurations
US8256243B2 (en) Integrated olefin recovery process
US5755115A (en) Close-coupling of interreboiling to recovered heat
US10315971B2 (en) Process for recovering heat from a hydrocarbon separation
SA110310707B1 (en) Hydrocarbon gas processing
WO2012075266A2 (en) Ngl recovery from natural gas using a mixed refrigerant
US20110036120A1 (en) Method and apparatus for recovering and fractionating a mixed hydrocarbon feed stream
MX2007000242A (en) Configurations and methods for gas condensate separation from high-pressure hydrocarbon mixtures.
CA2388266C (en) System and method for liquefied petroleum gas recovery
US3813890A (en) Process of continuous distillation
US2916888A (en) Hydrocarbon purification process
CA2517261C (en) Improved distillation sequence for the purification and recovery of hydrocarbons
JPH07258119A (en) Recovery of ethylene
JP5793139B2 (en) Hydrocarbon gas treatment
US11066346B2 (en) Method and system for obtaining one or more olefins
JP5802259B2 (en) Hydrocarbon gas treatment
JP5552160B2 (en) Hydrocarbon gas treatment
EP1009963B1 (en) Process for separating hydrocarbons and for the production of a refrigerant
US6487876B2 (en) Method for providing refrigeration to parallel heat exchangers
US11060037B2 (en) Method for purifying a gas rich in hydrocarbons
MXPA96004439A (en) Lightweight component washed in ale plaque decalor exchangers

Legal Events

Date Code Title Description
FZDE Dead

Effective date: 20131224