Method For Trapping CO2 By Solid Cryocondensation In A Turbine

Abstract

The present invention relates to a method of capturing carbon dioxide in a fluid comprising at least one compound more volatile than carbon dioxide CO2, for example methane CH4, oxygen O2, argon Ar, nitrogen N2, carbon monoxide CO, helium He and/or hydrogen H2.

1 - 13 . (canceled) 
     
     
         14 . A method for producing at least one CO2-lean gas and one or more CO2-rich primary fluids from a process fluid containing CO2 and at least one compound more volatile than CO2, comprising:
 a) a first cooling of said process fluid by exchange of heat with no change in state;   b) a second cooling of at least part of said process fluid cooled in step a) so as to obtain at least one solid containing predominantly CO2 and at least said CO2-lean gas; and   c) a step comprising liquefaction and/or sublimation of at least part of said solid and making it possible to obtain said one or more CO2-rich primary fluids;   
       wherein step b) is performed in at least one expansion turbine, said solid forming inside said turbine. 
     
     
         15 . The method of  claim 14 , wherein said solid is in the form of carbon dioxide snow. 
     
     
         16 . The method of  claim 14 , wherein said expansion turbine comprises at least one rotor part and at least one stator part situated upstream of said rotor part, and in that step b) is performed in said rotor part. 
     
     
         17 . The method of  claim 16 , wherein said process fluid comprising CO2 and at least one compound more volatile than CO2 remains in the vapor state in said stator part. 
     
     
         18 . The method of  claim 16 , wherein said process fluid is in the supersaturated vapor state in said stator part situated upstream of said rotor part. 
     
     
         19 . The method of  claim 16 , further comprising, a step b1), after step b), in which said solid comprising predominantly CO2 and said CO2-lean gas that were obtained in step b) are separated into at least one CO2-rich fraction and a CO2-lean fraction), said step b1) being performed in a region situated downstream of said rotor part. 
     
     
         20 . The method of  claim 19 , wherein in step b), a rotational movement is imparted to said solid comprising predominantly CO2 and to said CO2-lean gas and in that, in step b1), the separation of said solid containing predominantly CO2 from said CO2-lean gas, both obtained in step b), comprises a separation through a centrifugal effect induced by the rotational movement imparted, in step b), to said solid comprising predominantly CO2. 
     
     
         21 . The method of  claim 14 , wherein certain parts of said turbine are heated. 
     
     
         22 . The method of  claim 14 , wherein said turbine comprises surfaces that are polished and/or that are coated with a given material aimed at limiting heterogeneous nucleation of said solid comprising predominantly CO2 on said surfaces and/or on said coating material. 
     
     
         23 . The method of  claim 14 , wherein said process fluid comprises compounds less volatile than CO2 and in that said method comprises, prior to step b), one or more steps of purifying said process fluid to remove said less volatile compounds. 
     
     
         24 . The method of  claim 14 , wherein said turbine comprises titanium. 
     
     
         25 . The method of  claim 14 , wherein a sweeping gas is injected into said turbine, said sweeping gas coming into contact with said process fluid. 
     
     
         26 . The method of  claim 14 , wherein said turbine has a degree of reaction in excess of 50%.