Process and apparatus for air separation

Abstract

A first process stream of the air separation is compressed in a first compressor ( 2 ). The first compressor ( 2 ) is mechanically coupled ( 4 ) to a steam turbine ( 1 ) and to an electric motor ( 3 ).

1 . In a process for air separation comprising feeding air in, wherein feed air is fed to an air separation unit, and compressing a first process stream of the air separation is compressed in a first compressor ( 2 ), the improvement wherein said first compressor isbeing mechanically coupled ( 4 ) to a steam turbine ( 1 ) driven by an external fluid and to an electric motor ( 3 ).  
     
     
         2 . A process according to  claim 1 , wherein said first compressor is the main feed air compressor of said air separation unit.  
     
     
         3 . A process according to  claim 1 , wherein said first compressor is a booster air compressor of said air separation unit.  
     
     
         4 . A process according to  claim 1 , wherein said first compressor is a product gas compressor of said air separation unit.  
     
     
         5 . A process according to  claim 1 , wherein said a first process stream is feed air for said air separation unit.  
     
     
         6 . A process according to  claim 1 , wherein said a first process stream is a product gas of said air separation unit.  
     
     
         7 . A process according to  claim 1 , wherein said a first process stream is a recycle gas of said air separation unit.  
     
     
         8 . A process according to  claim 1 , wherein during at least a first operating period, electric energy is supplied to the motor.  
     
     
         9 . A process according to  claim 1 , wherein the electric motor ( 3 ) is a motor/generator and wherein during at least a second operating period, electric energy is withdrawn from the motor/generator.  
     
     
         10 . A process according to  claim 2 , wherein the electric motor ( 3 ) is a motor/generator and wherein during at least a second operating period, electric energy is withdrawn from the motor/generator.  
     
     
         11 . A process according to  claim 1 , wherein a second process stream of the air separation is compressed in a second compressor ( 5 ) and the second compressor is mechanically coupled to the first compressor ( 2 ).  
     
     
         12 . A process according to  claim 11 , wherein the mechanical coupling between the second compressor ( 5 ) and the first compressor ( 2 ) is realized by a gear system ( 6 ).  
     
     
         13 . In an apparatus for air separation comprising a first compressor ( 2 ) and means for connecting the inlet or the outlet of the first compressor to an air separation unit, the improvement wherein the first compressor ( 2 ) is mechanically coupled to a steam turbine ( 1 ) for work expansion of a fluid and to an electric motor ( 3 ).  
     
     
         14 . An apparatus according to  claim 13 , wherein the electric motor ( 3 ) is a motor/generator.  
     
     
         15 . An apparatus according to  claim 13 , further comprising a second compressor ( 5 ) which is mechanically coupled to the first compressor ( 2 ).  
     
     
         16 . An apparatus according to  claim 14 , further comprising a second compressor ( 5 ) which is mechanically coupled to the first compressor ( 2 ).  
     
     
         17 . An apparatus according to  claim 15 , wherein the mechanical coupling between the second compressor ( 5 ) and the first compressor ( 2 ) is realized by a gear system ( 6 ).  
     
     
         18 . An apparatus according to  claim 16 , wherein the mechanical coupling between the second compressor ( 5 ) and the first compressor ( 2 ) is realized by a gear system ( 6 ).  
     
     
         19 . An apparatus for compressing and expanding fluids, comprising a first compressor ( 2 ), a steam turbine ( 1 ), a second compressor ( 5 ), and a electric motor ( 3 ), all being mechanically coupled ( 4   a,    4   b,    6 ).  
     
     
         20 . An apparatus according to  claim 19 , wherein 
 the first compressor ( 2 ) and the turbine ( 1 ) are mechanically coupled by a common shaft ( 4   a ),    the second compressor ( 5 ) and the electric motor ( 3 ) mechanically coupled by a common shaft ( 4   b ), and    the compressor-turbine combination and the compressor-motor combination are mechanically coupled via a gear system ( 6 ).    
     
     
         21 . Apparatus according to  claim 19 , whereby the electric motor ( 3 ) is a motor/generator.  
     
     
         22 . Apparatus according to  claim 20 , whereby the electric motor ( 3 ) is a motor/generator.