Method and device for separation at sub-ambient temperature

Abstract

In a method for separation at sub-ambient temperature, a mixture of fluid at sub-ambient temperature is sent to a system of separation columns comprising at least one separation column, a fluid enriched in a lighter component of the mixture leaves the top of one column of the system and a fluid enriched in a heavier component is withdrawn from the bottom of one column of the system, the cold source of a heat pump using the magnetocaloric effect is thermally connected to a first zone of one column of the system and the hot source of the same heat pump is thermally connected to a second zone of the same or of another column of the system.

1 - 15 . (canceled) 
     
     
         16 . A method for separation at sub-ambient temperature, the method comprising the steps of:
 sending a mixture of fluid at sub-ambient temperature into a system of separation columns comprising at least one separation column; and   withdrawing a fluid enriched in a lighter component of the mixture from the top of one column of the system and withdrawing a fluid enriched in a heavier component from the bottom of one column of the system;   wherein the cold source of a heat pump using the magnetocaloric effect is directly or indirectly thermally connected to a first zone of a column of the system and the hot source of the same heat pump is directly or indirectly thermally connected to a second zone of the same or of another column of the system,   wherein the minimum temperature of the first zone is lower than the maximum temperature of the second zone.   
     
     
         17 . The method as claimed in  claim 16 , in which a gas of the first zone condenses at least partially and is possibly sent back to the first zone. 
     
     
         18 . The method as claimed in  claim 16 , in which a liquid of the second zone is vaporized at least partially and is possibly sent back to the second zone. 
     
     
         19 . The method as claimed in  claim 16 , in which at least a fluid coming from the first or second zone is placed in direct contact with a magnetocaloric material of a heat pump using the magnetocaloric effect. 
     
     
         20 . The method as claimed in  claim 16 , in which the exchange of heat is performed at least in part between a fluid coming from the first or second zone and a heat-transfer fluid that has been in contact with a magnetocaloric material of a heat pump using the magnetocaloric effect via an exchanger. 
     
     
         21 . The method as claimed in  claim 16 , in which the exchange of heat is performed at least in part between a fluid coming from the first or second zone and a heat-transfer fluid that has been in contact with a magnetocaloric material of a heat pump using the magnetocaloric effect through an intermediate heat-transfer circuit. 
     
     
         22 . The method as claimed in  claim 16 , in which the mixture is air. 
     
     
         23 . The method as claimed in  claim 22 , in which the heat pump using the magnetocaloric effect condenses a nitrogen-enriched gas in the first zone and vaporizes an oxygen-enriched liquid in the second zone. 
     
     
         24 . The method as claimed in  claim 16 , in which a plurality of heat pumps is employed, heat being supplied to several heat pumps from a first zone and/or heat coming from several heat pumps being sent to a second zone. 
     
     
         25 . The method as claimed in  claim 16 , in which the main components of the mixture are carbon monoxide and/or carbon dioxide and/or hydrogen and/or methane and/or nitrogen. 
     
     
         26 . The method as claimed in  claim 16 , in which in order to produce a liquid in the bottom of the column containing more than 97 mol % oxygen, argon is removed from the liquid withdrawn at the bottom of the column by separating an argon-enriched intermediate gas from the column in a distillation column in order to produce a flow that is more rich in argon. 
     
     
         27 . The method as claimed in  claim 16 , in which use is made of several heat pumps using the magnetocaloric effect, one of which is used to condense an intermediate gas tapped off higher up the column and another is used to vaporize an intermediate liquid from lower down the column. 
     
     
         28 . The method as claimed in  claim 16 , to produce a column bottom liquid containing less than 96.5 mol % oxygen, in which a heat pump using the magnetocaloric effect is used to vaporize an intermediate liquid from lower down the column. 
     
     
         29 . The method as claimed in  claim 16 , in which the hot source operates at the highest temperature of the heat pump. 
     
     
         30 . A device for separation at sub-ambient temperature, comprising a system of separation columns comprising at least one separation column to which a mixture of fluid at sub-ambient temperature is sent, a pipe for withdrawing a fluid enriched with a lighter component of the mixture from the top of one column of the system and a pipe for withdrawing a fluid enriched in a heavier component from the bottom of one column of the system, in which the cold source of a heat pump using the magnetocaloric effect is directly or indirectly thermally connected to a first zone of a column of the system and the hot source of the same heat pump being directly or indirectly thermally connected to a second zone of the same or of another column of the system, the arrangement of the first and second zones in the column or columns being such that the minimum temperature of the first zone is lower than the maximum temperature of the second zone.