Liquefactor and method for liquefying a gas

Abstract

A liquefactor for a gas includes a framework (O) containing at one end at least one plate-and-fin heat exchanger (E), each plate having a length and a width, and the plates being arranged with their length parallel to the length of the framework and at the other end a turbine (M) to provide cold to the at least one heat exchanger, the framework being orientated such that the turbine is positioned beneath the at least one exchanger.

What is claimed is: 
     
         1 . A liquefactor for a gas that is liquefied at a cryogenic temperature, comprising an assembly comprising a framework, the framework having a substantially elongate parallelepiped shape and having a main axis corresponding to its length and two ends, the framework not containing a distillation column, and inside the framework:
 i) at one end of the framework at least one plate-and-fin heat exchanger, each plate having a length and a width, and the plates being arranged with their length parallel to the axis of the framework,   ii) a line for sending a gas to be liquefied to the at least one heat exchanger,   iii) a line for removing a cooled or liquefied gas from the at least one heat exchanger,   iv) a support mounted inside the framework,   v) at least one turbine, the turbine being fastened to the support and being arranged to drive a compressor arranged outside the framework, the turbine being connected to the at least one exchanger to send a gas cooled or heated in the at least one heat exchanger to be expanded in the turbine and/or to send a gas expanded in the turbine from the turbine to the at least one heat exchanger,   vi) at least one cooler connected to cool gas compressed in the compressor,   vii) a means for conveying a refrigerant to the cooler, and   viii) wherein the turbine is positioned at another end of the framework and the cooler is positioned between the turbine and the at least one heat exchanger, or b) the cooler is positioned at another end of the framework and the turbine is positioned between the cooler and at least one heat exchanger,   wherein the framework is positioned with the main axis vertical, the at least one heat exchanger being positioned above the at least one turbine and the at least one cooler, the line for sending a gas to be liquefied to the heat exchanger in the framework and a means connected to the heat exchanger to remove a liquefied gas from the framework.   
     
     
         2 . The liquefactor according to  claim 1 , comprising at least one partition dividing the framework into at least two portions, the partition having the shape of a rectangular plate arranged perpendicular to the axis of the framework, the partition acting as support for the turbine if the cooler is at the other end of the framework or for the cooler if the turbine is at the other end of the framework, the turbine and the cooler being separated from one another by the partition. 
     
     
         3 . The liquefactor according to  claim 1 , further comprising fastening feet connected to the other end of the framework to place the framework on a foundation. 
     
     
         4 . The liquefactor according to  claim 1 , further comprising a means for fluidically connecting the exchanger to the compressor to convey a gas cooled in the exchanger to the compressor. 
     
     
         5 . The liquefactor according to  claim 1 , further comprising a means for fluidically connecting the exchanger to the turbine to convey a gas expanded in the turbine to the exchanger. 
     
     
         6 . The liquefactor according to  claim 1 , wherein the framework is divided into at least three compartments, each compartment having a dimension that is a portion of the length of the framework, the at least one heat exchanger being in one of the at least three compartments, the turbine in another of the at least three compartments and the at least one cooler in another of the at least three compartments, the compartments containing the turbine, and the at least one cooler forming a parallelepiped wider than the parallelepiped formed by the compartment containing the heat exchanger. 
     
     
         7 . The liquefactor according to  claim 6 , further comprising a fourth compartment containing neither a heat exchanger nor a turbine, but containing connection lines between the at least one heat exchanger and another element, which may be the at least one turbine. 
     
     
         8 . The liquefactor according to  claim 7 , wherein the turbine is positioned at another end of the framework and is connected to the fourth compartment via a compartment arranged side by side with the compartment containing the cooler. 
     
     
         9 . The liquefactor according to  claim 1 , wherein the framework is at least 10 m long, the cooler and the turbine occupying a portion of the length of the framework equal to at least 4 m. 
     
     
         10 . The liquefactor according to  claim 1 , wherein the at least one heat exchanger is thermally insulated. 
     
     
         11 . A method for liquefying a gas at a cryogenic temperature, using an assembly comprising a framework, the framework having a substantially elongate parallelepiped shape and having a main axis corresponding to its length and two ends, the framework not containing a distillation column, and inside the framework:
 i) at one end of the framework at least one plate-and-fin heat exchanger, each plate having a length and a width, and the plates being arranged with their length parallel to the axis of the framework,   ii) a line for sending a gas to be liquefied to the at least one heat exchanger,   a line for removing a cooled or liquefied gas from the at least one heat exchanger,   iv) a support mounted inside the framework,   v) at least one turbine, the turbine being fastened to the support and being arranged to drive a compressor arranged outside the framework, the turbine being connected to the at least one exchanger to send a gas cooled or heated in the at least one heat exchanger to be expanded in the turbine and/or to send a gas expanded in the turbine from the turbine to the at least one heat exchanger,   vi) at least one cooler connected to cool gas compressed in the compressor,   vii) a) the turbine is positioned at another end of the framework and the cooler is positioned between the turbine and the at least one heat exchanger, or b) the cooler is positioned at another end of the framework and the turbine is positioned between the cooler and at least one heat exchanger,   viii) the framework being positioned with its main axis vertical, the at least one heat exchanger being positioned above the at least one turbine and the at least one cooler,   wherein a gas to be liquefied is sent to the heat exchanger in the framework and a liquefied gas is removed from the heat exchanger, a refrigerant is conveyed to the cooler and cold is provided for the liquefaction by expanding a gas in the at least one turbine, the gas having been cooled or heated in the at least one heat exchanger and/or a gas expanded in the turbine being sent to the at least one heat exchanger.   
     
     
         12 . An apparatus for separating air by cryogenic distillation comprising a system of columns, a liquefactor according to  claim 1 , and a means for sending a nitrogen-rich gas to the liquefactor from the column system as gas to be liquefied. 
     
     
         13 . The apparatus according to  claim 12 , further comprising a means for sending a gas liquefied in the liquefactor to the system of columns.