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
• • 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
  • F25J3/04—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 for air
  • F25J3/04151—Purification and (pre-)cooling of the feed air; recuperative heat-exchange with product streams
  • F25J3/04242—Cold end purification of the feed air
• • 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
  • F25J1/00—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures
  • F25J1/02—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures requiring the use of refrigeration, e.g. of helium or hydrogen ; Details and kind of the refrigeration system used; Integration with other units or processes; Controlling aspects of the process
• • 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
  • F25J3/04—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 for air
  • F25J3/04151—Purification and (pre-)cooling of the feed air; recuperative heat-exchange with product streams
  • F25J3/04187—Cooling of the purified feed air by recuperative heat-exchange; Heat-exchange with product streams
• • 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
  • F25J3/04—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 for air
  • F25J3/04248—Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion
  • F25J3/04278—Generation of cold for compensating heat leaks or liquid production, e.g. by Joule-Thompson expansion using external refrigeration units, e.g. closed mechanical or regenerative refrigeration units
• • 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
  • F25J3/04—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 for air
  • F25J3/044—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 for air using a single pressure main column system only
• • 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
  • F25J3/08—Separating gaseous impurities from gases or gaseous mixtures or from liquefied gases or liquefied gaseous mixtures
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
  • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
  • F25J2200/00—Processes or apparatus using separation by rectification
  • F25J2200/40—Features relating to the provision of boil-up in the bottom of a column
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
  • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
  • F25J2200/00—Processes or apparatus using separation by rectification
  • F25J2200/50—Processes or apparatus using separation by rectification using multiple (re-)boiler-condensers at different heights of the column
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
  • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
  • F25J2200/00—Processes or apparatus using separation by rectification
  • F25J2200/74—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
  • F25J2205/04—Processes or apparatus using other separation and/or other processing means using simple phase separation in a vessel or drum in the feed line, i.e. upstream of the fractionation step
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
  • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
  • F25J2205/00—Processes or apparatus using other separation and/or other processing means
  • F25J2205/10—Processes or apparatus using other separation and/or other processing means using combined expansion and separation, e.g. in a vortex tube, "Ranque tube" or a "cyclonic fluid separator", i.e. combination of an isentropic nozzle and a cyclonic separator; Centrifugal separation
• • 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
  • F25J2205/20—Processes or apparatus using other separation and/or other processing means using solidification of components
• • 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
  • F25J2210/40—Air or oxygen enriched air, i.e. generally less than 30mol% of O2
• • 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
  • F25J2215/04—Recovery of liquid products
• • 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
  • F25J2220/00—Processes or apparatus involving steps for the removal of impurities
• • 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
  • F25J2220/00—Processes or apparatus involving steps for the removal of impurities
  • F25J2220/40—Separating high boiling, i.e. less volatile components from air, e.g. CO2, 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
  • F25J2230/00—Processes or apparatus involving steps for increasing the pressure of gaseous process streams
  • F25J2230/32—Compression of the product 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
  • F25J2230/00—Processes or apparatus involving steps for increasing the pressure of gaseous process streams
  • F25J2230/52—Processes or apparatus involving steps for increasing the pressure of gaseous process streams the fluid being oxygen enriched compared to air, e.g. "crude oxygen"
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
  • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
  • F25J2270/00—Refrigeration techniques used
  • F25J2270/90—External refrigeration, e.g. conventional closed-loop mechanical refrigeration unit using Freon or NH3, unspecified external refrigeration
  • F25J2270/908—External refrigeration, e.g. conventional closed-loop mechanical refrigeration unit using Freon or NH3, unspecified external refrigeration by regenerative chillers, i.e. oscillating or dynamic systems, e.g. Stirling refrigerator, thermoelectric ("Peltier") or magnetic refrigeration

Definitions

• the present invention relates to a process for purifying, cooling and separating a gaseous mixture and to a purification and cooling apparatus a gaseous mixture.
• a gaseous mixture has to be cooled to a temperature below the liquefaction temperature, or even solidification of one of the gaseous components that it contains, this poses particular problems.
• the heat exchanger used for cooling the gaseous mixture is, for example, a plate and fin exchanger comprising passages in which the gaseous mixture cools, these passages may be obstructed by the formation of solids on the walls. passages.
• An object of the present invention is to propose an alternative to conventional schemes for purifying and cooling, or even liquefying, a gaseous mixture.
• An object of the present invention is to provide an alternative to conventional purification schemes of air separation units and other separation and / or liquefaction units, operating at low temperature.
• these liquefaction units include air liquefaction units (for example for energy storage, liquefaction of a gas produced by separating air, for example nitrogen and liquefaction of natural gas.
• Other examples of the separation units include for example, the units for separating a mixture of carbon dioxide containing at least 30% of carbon dioxide as well as hydrogen and / or methane and / or oxygen and / or carbon monoxide at room temperature subambient.
• the separation units may also be cryogenic separation units of mixtures of hydrogen and / or carbon monoxide and / or nitrogen and / or methane, the mixture containing at least 10 mol% of at least one of these components.
• polytetrafluoroethylene also known as Teflon®
• Teflon® allows low adhesion of ice due to low surface tension as described in MG Ferrick, ND Mulherin, BA Coutermarsh, GD Durell, LA Curtis, TL St. Clair, ES Weiser, RJ Cano, Smith TM, CG Stevenson and EC Martinez, Journal of Adhesion Science and Technology, 26 (2012) 473.
• the NUSIL ® R2180 coating based on polysiloxane also significantly reduces the ice adhesion. Similar results were obtained using another amorphous carbon (DLC) coating as described in US-A-8524318.
• DLC amorphous carbon
• surfaces that reduce ice adhesion are generally hydrophobic or superhydrophobic as described in L. Foroughi Mobarakeh, R. Jafari and M. Farzaneh, Applied Surface Science, 284 (2013) 459.
• Another type of surface reduces the adhesion of ice, it is the lubricated surfaces.
• the surface is impregnated with a fluorocarbon-based lubricant such as Krytox® or silicone oils as described in WO-A-2012/100100 and US-A-2006/0281861.
• the ice is in contact with the lubricant, i.e. a liquid phase, thus the adhesion forces are very low.
• the lubricant also has another advantage, it improves the erosion resistance of the surfaces.
• the ice formation temperature can be lowered with salt or glycol compounds. It turns out that a similar phenomenon can occur when a polymer compound, usually a hygroscopic polymer is grafted to a surface. This type of coating can lower the ice formation temperature and reduce the amount of ice formed.
• the most well-known coatings on this subject are of the glycol type (US-A-2010/0086789) but coatings inspired by the structure of the anti-icing proteins have a similar effect as described in L. Makkonen, Journal of Adhesion Science and Technology, 26 (2012) 413.
• GB-A-917286 discloses a low temperature separation process in which a gas containing carbon dioxide is cooled by two exchangers in turn, each allowing a heat exchange between only two fluids and each comprising an area designed to prevent carbon dioxide deposition.
• the heat exchanger of GB-A-917286 necessarily consists of at least two exchange bodies and can not be monobloc.
• a low temperature separation takes place at at most 0 ° C, or at least
• the "hot end” is the part of the heat exchanger that is operating at a maximum average temperature.
• the “cold end” is that part of the heat exchanger that is operating at a minimum average temperature.
• a heat exchanger is a single exchange body or a plurality of exchange bodies, capable of performing a heat exchange.
• the gaseous mixture to be cooled returns to the hot end of the exchanger and comes out, usually at the cold end.
• a heat exchanger is mounted so that its hot end is up and its cold end down.
• the present invention may require having the hot end at the bottom and the cold end at the top.
• the heat exchanger is generally disposed within a thermally insulated cold box.
• Other elements of a separation apparatus may also be in the cold box, for example, a distillation column.
• the gaseous mixture cools in each exchange body having cooling passages designed to reduce the adhesion of the solidified impurity to a surface of the passages and / or
• each exchange body having cooling passages designed to reduce the adhesion of the solidified impurity to a surface of the passages.
• the gaseous mixture withdrawn contains at least part of the solidified impurity
• the gaseous mixture comprises at least one component, preferably a major component, which does not solidify and possibly does not liquefy in the heat exchanger
• the gaseous mixture comprises at least two components, preferably major components, which do not solidify and possibly do not liquefy in the heat exchanger
• an impurity is a component which does not represent more than 10%, mol or 5% mol or even 1% mol or even 0.1% mol or even 0.01% mol of the gaseous mixture.
• the gaseous mixture is purified to remove at least a fraction of the at least one impurity upstream of the heat exchanger, this fraction representing between 20% and 95% of the impurity contained in the gaseous mixture upstream of the process.
• the gaseous mixture is not purified to remove at least a fraction of the at least one impurity upstream of the heat exchanger
• the solidified impurity is collected downstream of the heat exchanger by means of a phase separator and / or a worm cooling passages are at least partially physically modified, the treatment serving to limit or even prevent the formation and / or adhesion of the solidified impurity on a surface of the passages
• the cooled gas mixture downstream of the heat exchanger and / or at least one intermediate level of the heat exchanger is treated to remove the impurity in gaseous and / or liquid and / or solid form.
• the cooled gaseous mixture is treated solely downstream of the heat exchanger and not at least at an intermediate level of the heat exchanger in order to eliminate the impurity in gaseous and / or liquid and / or solid form.
• the cooled gas mixture is treated solely at at least one intermediate level of the heat exchanger and not downstream of the heat exchanger to remove the impurity in gaseous and / or liquid and / or solid form.
• the gas mixture is cooled in the heat exchanger first to a temperature less than or equal to the liquefaction temperature of the at least one impurity but above its solidification temperature, the gas mixture is removed from the exchanger to remove a portion of the impurity in liquid form and returns the gaseous mixture containing impurity in the heat exchanger to cool to the solidification temperature thereof.
• hot end At most 80%, at most 50%, or even at most 30%, or even at most 10% of the impurity present at the inlet of the heat exchanger, called hot end, are removed by collecting it at least once intermediate point of the heat exchanger after cooling, in solid and / or liquid form
• the hot end of the heat exchanger is disposed at a higher level than the cold end.
• the hot end of the heat exchanger is disposed at a lower level than that of the cold end or that of an intermediate level of the exchanger in the case of an inverted U-shaped exchanger and is eliminated at least 50% the impurity, for example water, present in the gaseous mixture to be cooled at the inlet of the heat exchanger, said hot end, by collecting it in solid or liquid form at the hot end of the exchanger where it falls by gravity after cooling in the heat exchanger (because its adhesion to the walls is limited).
• the hot end of the heat exchanger is arranged at the same level as the cold end in the case of an inverted U-shaped exchanger
• the gaseous mixture is air or a mixture whose main components are hydrogen and / or carbon monoxide and / or methane and the at least one impurity is water and / or carbon dioxide; carbon or a mixture whose main component is carbon dioxide and optionally hydrogen and / or carbon monoxide and / or methane and / or oxygen and / or nitrogen and / or argon and the at least one impurity is water.
• At least one surface of the cooling passages has been treated to make it rougher and / or to lubricate and / or to render it hydrophilic and / or hydrophobic and / or hydroscopic and / or hygroscopic so as to limit or even prevent formation and / or the adhesion of solidified impurities, for example ice.
• the heat exchanger may comprise passages of which at least one section has a treatment and / or a coating and / or a geometry and / or, in the case of a plate and fin exchanger, a type of fins which differs from that of another section to operate at a lower temperature range.
• the heat exchanger may comprise passages of which at least one section has a treatment and / or a coating and / or a geometry and / or, in the case of a plate and fin heat exchanger, a type of fins which differs from that of another section located downstream of an intermediate withdrawal point of solidified impurities.
• the gaseous mixture is purified and cooled by a process as described above, optionally further cooled and sent to a column system to be separated by distillation at low temperature or even cryogenic temperature to produce at least one fluid enriched in a component of the gas mixture.
• the fluid enriched in a component of the gaseous mixture heats up in the heat exchanger in the warming passages.
• the heat exchanger comprises at least one heating passage of a fluid, the at least one heating passage having not been treated or coated to limit or even prevent the formation and / or adhesion of impurities solidified, for example ice.
• At least a portion of the solidified impurity exiting the cooling passages of the heat exchanger is returned to the heat exchanger to heat up.
• the at least a portion of the solidified impurity is mixed with another gas prior to heating in the heat exchanger.
• the at least one heating passage to which the solidified impurities are sent has been treated or coated to limit or even prevent the formation and / or adhesion of solidified impurities, for example ice.
• the gas mixture is liquefied or liquefied by a subsequent step of downstream of the exchanger and / or is separated at a subambient temperature downstream of the exchanger, optionally after removal downstream of the remaining impurity exchanger which would solidify at this subambient temperature.
• frigories are provided to the gaseous mixture which cools to at least one intermediate point of the heat exchanger.
• coolants are supplied to the gaseous mixture which cools to at least one intermediate point of the heat exchanger, preferably downstream or upstream of a draw-off point of at least a portion of the solidified or liquefied impurity at a intermediate level of the heat exchanger.
• frigories are provided to the gas mixture by removing at least a portion of the gaseous mixture from the heat exchanger and cooling it.
• Frigories are provided to the gas mixture by means of a refrigerant sent to an intermediate level of the heat exchanger.
• the gaseous mixture cools in the heat exchanger intermittently
• the heat exchanger cools the gaseous mixture to the cold end until a temperature below 0 ° C, or even below -50 ° C, or even below -100 ° C.
• the gaseous mixture is at atmospheric pressure or a pressure greater than atmospheric pressure
• the heat exchanger comprises only one exchange body and is a monobloc exchanger
• the heat exchanger comprises at least two exchange bodies the gaseous mixture cools in cooling passages whose number does not equal the number of heating passages connected to the means of transport of the first gas
• the gaseous mixture cools in cooling passages whose number does not equal the number of heating passages connected to the means of transport of the second gas.
• the passages of the heat exchanger are treated to limit the deposition of impurities but not to prevent it completely, it will be necessary to remove the solids formed in the passages, for example by heating and / or passing the gaseous mixture at a sufficient flow rate (its nominal flow rate or a higher flow rate) and / or at a high pressure with respect to the flow rate and / or pressure used during cooling or by mechanical means, for example the variation of the gas mixture flow rate or the gas mixture flow rate pulsations, or the vibrations applied directly to the exchanger.
• a sufficient flow rate its nominal flow rate or a higher flow rate
• mechanical means for example the variation of the gas mixture flow rate or the gas mixture flow rate pulsations, or the vibrations applied directly to the exchanger.
• an apparatus for cooling and purifying a gas mixture containing at least one impurity comprising a heat exchanger having cooling passages of the gas mixture and heating passages of a gas, means for sending the gaseous mixture containing at least one impurity to cool in the heat exchanger to a temperature equal to or less than that at which the at least one impurity solidifies and means for withdrawing the gaseous mixture , optionally at least partially liquefied, of the heat exchanger, preferably at the cold end and means for collecting at least a portion of the solidified impurity exiting the cooling passages of the heat exchanger and / or at a intermediate of the heat exchanger and means for discharging the gas mixture into the at least one impurity of the heat exchanger characterized in that the pa cooling parts are at least partially coated and / or physically treated and / or chemically treated, the coating and / or treatment serving to limit or even prevent the formation and / or adhesion of the solidified impurity to a surface of
• the apparatus comprises heating passages for a first gas and heating passages for a second gas
• the apparatus comprises means for purifying the gaseous mixture upstream of the heat exchanger in order to remove at least a fraction of the at least one impurity.
• the means for collecting at least a portion of the solidified impurity downstream of the heat exchanger are constituted by a phase separator and / or a worm.
• the heat exchanger is constituted by at least one plate and fin heat exchanger
• the heat exchanger consists of at least two plate and fin heat exchangers made of aluminum or copper or titanium
• the heat exchanger is constituted by at least one coil heat exchanger
• the heat exchanger is constituted by at least one shell and tube heat exchanger
• the apparatus comprises means for treating the cooled gaseous mixture downstream of the heat exchanger and / or at least an intermediate level of the heat exchanger to remove impurity in gaseous and / or liquid form and / or solid.
• the hot end of the heat exchanger is disposed at a higher level than the cold end.
• the hot end of the heat exchanger is disposed at a lower level than that of the cold end or that of an intermediate level of the exchanger in the case of an inverted U-shaped exchanger and is eliminated at least 50% the impurity, for example water, present in the gaseous mixture to be cooled at the inlet of the heat exchanger, said hot end, by collecting it in solid or liquid form at the hot end of the exchanger where it falls by gravity after cooling in the heat exchanger.
• At least one surface of the cooling passages has been treated to make it rougher and / or to lubricate it and / or to have a hydrophobic and / or superhydrophobic surface, and / or with hydrophobic and hydrophilic and / or hygroscopic zones in order to limit or even prevent the formation and / or adhesion of solidified impurities, for example ice.
• the surface of a passage may be impregnated with a lubricant or not.
• the exchanger comprises at least one heating passage of a fluid and at least one surface of the at least one heating passage has been treated to make it rougher and / or to lubricate it and / or to make it hydrophilic and and / or hydrophobic and / or hydroscopic and / or hygroscopic so as to limit or even prevent the formation and / or adhesion of solidified impurities, for example ice.
• a low temperature distillation or even cryogenic temperature separation apparatus comprising a cooling and purification apparatus as described above as well as a column system and means for send the purified and cooled gas mixture through the cooling and purification apparatus to the column system.
• the separation apparatus may not comprise means for cooling the gaseous mixture downstream of the cooling and purification apparatus.
• the apparatus may include means for supplying a fluid enriched in a component of the gaseous mixture to heat in the heat exchanger in warming passages.
• the heat exchanger comprises at least one heating passage of a fluid, the at least one heating passage having not been treated or coated to limit or even prevent the formation and / or adhesion of solidified impurities , for example ice cream.
• the apparatus comprises means for sending at least a portion of the solidified impurity exiting the cooling passages of the heat exchanger to the heat exchanger to heat up.
• the at least one heating passage to which the solidified impurities are sent has been treated or coated to limit or even prevent the formation and / or adhesion of solidified impurities, for example ice.
• the separation and purification apparatus may comprise means for supplying frigories to the gaseous mixture which cools to at least one intermediate point of the heat exchanger.
• the separation and purification apparatus may comprise means for supplying frigories to the gaseous mixture which cools to at least one intermediate point of the heat exchanger, preferably downstream and / or upstream of a draw-off point. at least a portion of the impurity solidified or liquefied at an intermediate level of the heat exchanger.
• the separation and purification apparatus may comprise means for supplying the gas mixture with frigories by removing at least a portion of the gaseous mixture from the heat exchanger.
• the separation and purification apparatus may comprise means for supplying frigories to the gas mixture by means of a refrigerant supplied to an intermediate level of the heat exchanger.
• the challenge is to compensate for the enthalpies of phase changes of the various components by the supply of energy (here cold booster) via external devices to the main exchanger (example: heat pump, cooling unit).
• Figure 12 is a diagram "compensated" by sufficient cold backups.
• Figure 12 is a simulation of the condensation and the solidification of water combined with the solidification of CO 2 .
• FIG 1 there is shown a cryogenic distillation air separation method using a plate and finned aluminum heat exchanger 3 and a single distillation column 27.
• This process allows the production of an enriched liquid in oxygen 43, an oxygen-enriched gas 45 and a nitrogen-enriched gas 47.
• the use of a plate-and-finned brazed aluminum heat exchanger is not essential.
• This exchanger can use other technologies and may for example be a wound heat exchanger or a shell and tube heat exchanger.
• the air to be separated 1 contains water and carbon dioxide, which must be purified upstream of the distillation.
• the compressed air 1 After filtering in a filter F and compression in a compressor C, the compressed air 1 enters the heat exchanger 3 constituted by a single exchange body and called "exchange line" without passing through adsorbent beds typically present in an air separation apparatus. It is conceivable to remove some of the water contained in the air by separating the water that condenses, during compression of the air followed by a cooling step. However, at least 20% of the water present in the ambient air will be removed by passing through the exchanger. The extraction of water on the one hand and the rest of the water and CO2 on the other hand are done at two different places in the exchange line 3.
• a large part of the water is removed in the form of liquid (about 75% of the water present in the air 1 arriving in the exchanger 3, after compression followed by a cooling step) at a temperature close to 0 ° C: the air 5 is withdrawn at this temperature.
• two cold additions are required via two heat pumps, for example at 0 ° C and -25 ° C.
• air 1 1 withdrawn at a colder intermediate level of the exchange line 3 cools with a second heat pump 6 fed by a fluid 13.
• the cooled air 1 1 A is returned to the 'exchange.
• the air already purified with water and cooled in two stages contains ice and solid carbon dioxide is sent to a phase separator 17 and ice and solid carbon dioxide 19 are removed.
• the walls of the cooling passages are treated to limit or prevent the formation and / or adhesion of ice and carbon dioxide on the surfaces, at least in regions where the temperature of the passage is expected to be below the solidification temperature of the water and / or carbon dioxide.
• This treatment may be a physical treatment of the surface or the establishment of a coating as described above, for example superhydrophobic.
• the solid water and carbon dioxide remain in the air and pass through the exchange line to the cold end before being collected in the second phase separator 17.
• Part of the secondary impurities in the air are also separated in the separator 17 at the cold end of the exchanger, either in solid form or in liquid form.
• the purified air 20 is divided into two parts 23, 25.
• the part 23 is sent to the middle of the simple distillation column 27 where it separates to form nitrogen-enriched gas at the top of the column 47 and a liquid enriched in nitrogen. oxygen 43 in the vat of column 27.
• Part 15 of the air is condensed at least partially in a heat exchanger 59 by heat exchange with a fluid flow 57 which cools by means of a heat pump 21 using the magnetocaloric effect.
• a cooling fluid 53 typically ambient air or cooling water is supplied to the heat pump 21 using the magnetocaloric effect. Heated water 55 leaves the heat pump 21.
• the column comprises a bottom reboiler 29 and a top condenser 31.
• the reboiler is heated by means of a fluid circuit 41 in connection with a heat pump using the magnetocaloric effect 33.
• This heat pump using the effect magnetocaloric 33 also serves to cool a fluid 37 which cools the top condenser 31.
• the fluids 37 and 41 may be the same or different.
• An oxygen-enriched liquid 43 is withdrawn in the vat from the column 19 and a nitrogen-enriched gas withdrawn via a pipe 47 is heated in the exchanger 3 and does not serve to regenerate a purification unit, since there do not have any.
• An oxygen-enriched gas 45 is withdrawn in the bottom of the column 27, is heated in the exchanger 3 and is compressed by a compressor 49.
• Figure 1a illustrates a variant of Figure 1 in which the heat exchanger 3 is constituted by two exchange bodies 3a, 3b.
• Each of the bodies 3a, 3b is a plate and fin heat exchanger as described above but other technologies can be envisaged.
• each of the bodies has cooling passages designed to reduce the adhesion of the solidified impurity to a surface of the passages.
• the cooling passages of each body 3a, 3b are at least partially coated and / or physically treated and / or chemically treated, the coating and / or treatment serving to limit or even prevent the formation and / or adhesion of the solidified impurity on a surface of the passages. It is conceivable to use more than two bodies.
• Carbon dioxide and / or solidified water (s) is collected for both bodies and sent to a single container 17.
• the use of several containers is obviously conceivable.
• the purified air of the two bodies is mixed to form the flow 20 and continues its treatment as for Figure 1.
• the gas 47 is heated simultaneously in the two exchange bodies during the distillation, being divided in two upstream of the bodies 3a, 3b and remixed downstream thereof.
• the gas 45 heats up simultaneously in the two exchange bodies during the distillation, being divided in two upstream of the bodies 3a, 3b and remixed downstream thereof.
• each passage receives only a gas to be heated or a gas to be cooled and the flow rates are not reversed during the distillation, the number of passages dedicated to the cooling of the air is not identical to the number of passages intended to reheat. the gas 47 for a given body.
• Figure 1b is schematically illustrated an exchange body corresponding to a body 3, 3a, 3b of one of the other Figures, where it can be seen that the number of passages dedicated to the cooling of the gaseous mixture, in this case air is not identical to the number of passages dedicated to the heating of the first gas, here nitrogen NR corresponding to nitrogen 47 or the number dedicated to the heating a second gas, here oxygen gas OG.
• the heat exchanger 3 is a monoblock heat exchanger which cools all the air intended for distillation during any period during which the distillation takes place. It also heats all the gas from the distillation during any period when the distillation takes place.
• the extraction of water on the one hand and the rest of the water and CO2 on the other hand are also at two different places in the exchange line 3. Now we remove a large part of the water in solid form (approximately 97% of the water present in the air 1 arriving in the exchanger 3) at a temperature close to -25 ° C, so in solid form.
• the air 5 is withdrawn at this point by separating the air and the ice 5B in a phase separator 2 and then the dried air 5A is reinjected to finish its cooling.
• the air sent to the separator 2 has already been cooled upstream by a first makeup of cold at 0 ° C.
• the air is first cooled in the exchange line 3, it is removed from the exchange line and water is removed in liquid form in the separator 2, it cools then the purified air 5A in the exchange line, then by a first cooler 4, then in the exchange line 3, then the air is purified to remove the water in the separator 8, it is cooled in the exchange line, then with a second cooler 6 and the air is cooled to the cold end.
• the solids or liquids 19 (the rest of the water, C0 2 and other secondary impurities) collected in the separator 17 are sent to the exchange line 3 to bring cold. This makes it possible to recover some of the latent heat, and thus to lighten or even simplify the necessary cold additions
• Figure 5 illustrates the case where a worm system 17A is used to extract impurities in the form of ice or a mixture of ice / liquid for reinjecting them directly into the products. This replaces the phase separator 17 of the other figures.
• the heat exchanger can cool the gas containing at least one impurity episodically and the impurity can be melted, for example while the heat exchanger is not working.
• the solid could also be evacuated by agreeing to lose some of the gaseous mixture that then carries the solid, with pneumatic style transport.
• Figure 6 is a variant where all the water and CO 2 present in the air at the hot end are removed at the cold end of the exchange line.
• the extra cold can be provided to compensate for the condensation and the solidification of impurities, as well as their cooling along the exchange line with a multitude of heat pumps, here n heat pumps PAC1, PACn powered by flow rates 9, 13.
• the addition of cold can also be done with a cold temperature slippery. It can also be limited to 1 or 2 colds.
• a portion of the impurities is removed by a conventional adsorption separation system A. This portion may comprise between 20% and 95% of an impurity or impurities present (s). Purification can be done by other means than adsorption.
• the fluid purified at least one impurity enters the exchange line where it ends removing the remaining impurities by solidification / liquefaction and final separation.
• At least one heat pump is always required to compensate for the latent heat of liquefaction and condensation of impurities.
• the impurities can be reinjected into the products, as seen in FIGS. 4 and 5. In the case where the majority of the impurities to be removed are removed upstream in a conventional system A, the cold filling can be done only at the cold end. of the exchanger 3.
• another separation system E is used at the outlet of the fan C to remove a portion of the impurities from the flow, for example in the form of a drying wheel. Then the fluid 1 still loaded with impurities enters the exchange line 3. The impurities are removed at two levels and heat pumps compensate for the latent heat of condensation and liquefaction of impurities. Frozen water / solid CO 2 and solid / liquid secondary impurities are recovered at the cold end without reinjecting it into the products.
• This variant does not use phase separators but generally requires cold input to the exchange line.
• the cold flow rates 45, 47 enter at the top of the exchange line and exit at the bottom.
• the figure is drawn as if the water and / or ice 19 descended through a passage other than the passage through which they are entered, present in the air.
• the exchange line 3 of FIG. 9 is divided into two (exchange line 3 and 3A) in order to draw off the water between the two. an intermediate temperature.
• the cooled air in the line 3 with a cold supply of the cooler 4 is separated in the phase separator to remove a portion of the water 5B.
• the rest of the water and / or ice falls down lines 3 and 3A.
• the at least partially purified air is cooled in the exchange line 3A with a cold supply of the cooler 6 and then cooled in the line 3A again.
• the phase separator 17 is not present in this particular case.
• the two lines 3,3A can be built with the same technology or different technologies (plate heat exchanger and fins, coil exchanger, heat exchanger calender).
• the exchange lines are of the same technology, they do not necessarily have the same construction and may differ in the size of the passages, the number of passages, the type of coating and / or treatment used to limit the deposit solids, the type of fins used, the material in which they are built, etc.
• the air separation apparatus may for example be a double air separation column producing at least one gaseous product and / or at least one liquid product.
• the invention can also be applied to the purification and cooling of other gaseous mixtures having at least one impurity liable to solidify during cooling.
• An impurity is a component which does not represent more than 10%, mol or 5% mol or even 1% mol or even 0.1% mol or even 0.01% mol of the gaseous mixture.
• the supply of cold can be carried out with any known and adapted means (for example, magneto-caloric cooler, conventional compression-expansion refrigeration unit, turbine).
• any known and adapted means for example, magneto-caloric cooler, conventional compression-expansion refrigeration unit, turbine.
• the heat exchanger 3 may comprise passages of which at least one section has a treatment and / or a coating and / or a geometry and / or a type of fins in the case of a plate heat exchanger. and fins which differs from that of another section to operate at a lower temperature range.
• the heat exchanger passage section at a temperature between 20 ° C to 0 ° C will be treated or coated in one way and that at a temperature between 0 ° C to -60 ° C will be treated in another way.
• the treatment or coating may be selected to suit the type of physical phenomenon change (gas-liquid, gas-solid, liquid-solid), or type of impurities concerned (eg water / carbon dioxide).
• the heat exchanger 3 may comprise passages of which at least one section has a treatment and / or a coating and / or a geometry and / or a type of fins in the case of a plate and fin heat exchanger which differs that of another section located downstream of an intermediate withdrawal point of solidified impurities.
• the heat exchanger may consist of at least two heat exchangers of different materials, for example a brazed aluminum heat exchanger and a brazed copper heat exchanger.
• the gaseous mixture cools in each exchange body having cooling passages designed to reduce the adhesion of the solidified impurity to a surface of the crossings

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• 2014
  • 2014-04-30 FR FR1454000A patent/FR3020669B1/fr not_active Expired - Fee Related
• 2015
  • 2015-04-30 CN CN201580023553.1A patent/CN106461321A/zh not_active Withdrawn
  • 2015-04-30 WO PCT/FR2015/051166 patent/WO2015166191A1/fr active Application Filing
  • 2015-04-30 US US15/305,849 patent/US20170045291A1/en not_active Abandoned
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