Liquid-continuous column distillation

Abstract

Bubble columns fractionate with vapor-liquid mass transfer efficiencies approaching that of distillation towers when vapor velocities in excess of 50% of jet flood are used. If the vapor velocities are pushed above about 70% of jet flood then the distillation performance of a given column packing becomes similar for both liquid continuous operation (bubble column mode) and vapor continuous operation (ordinary distillation tower mode).

The invention claimed is:  
     
         1 . An improvement in the distillation of mixtures comprising contacting a fractionatable liquid mixture in a distillation zone under conditions of temperature and pressure to fractionate said mixture vapor wherein the improvement comprises maintaining said distillation zone as liquid continuous and maintaining said vapor at a rate of greater than 50% of jet flood to less than 100% of jet flood.  
     
     
         2 . The distillation according to  claim 1  wherein said vapor rate is at least 70% of jet flood.  
     
     
         3 . The distillation according to  claim 1  wherein said mixture comprise organic compounds.  
     
     
         4 . The distillation according to  claim 4  wherein said mixture comprises hydrocarbons.  
     
     
         5 . The process of fractionating a liquid mixture comprising placing a liquid mixture in a fractionation zone under conditions of temperature and pressure to fractionate said mixture, maintaining a continuous liquid phase in said fractionation zone and a vapor having a rate through said fractionation zone of greater than 50% of jet flood to less than 100% of jet flood.  
     
     
         6 . The process according to  claim 5  wherein a solid component is present said fractionation zone.  
     
     
         7 . The process according to  claim 6  wherein said solid component comprises particulate material.  
     
     
         8 . The process according to  claim 7  wherein said particulate material comprises inert materials.  
     
     
         9 . The process according to  claim 7  wherein said particulate material comprises a catalyst and components of said mixture are reactive alone or with said vapor.  
     
     
         10 . The process according to  claim 9  wherein said catalyst comprises a slurry.  
     
     
         11 . The process according to  claim 9  wherein said catalyst comprises a fluidized bed.  
     
     
         12 . The process according to  claim 9  wherein said catalyst comprises a distillation structure.  
     
     
         13 . The process according to  claim 6  wherein said solid component comprises a plurality of distillation structures.  
     
     
         14 . The process according to  claim 6  wherein said solid component comprises a plurality of trays.  
     
     
         15 . The process according to  claim 9  wherein said catalyst comprises a slurry in combination with a packing.  
     
     
         16 . The process according to  claim 6  wherein said solid component comprises packing structures.  
     
     
         17 . The process according to  claim 6  wherein said packing structures comprises heat exchanger bundles.  
     
     
         18 . The process according to  claim 17  wherein a slurry of is present.  
     
     
         19 . The process according to  claim 5  wherein said vapor rate is greater than 70% of jet flood.  
     
     
         20 . The distillation according to  claim 9  wherein said mixture comprise 
 organic compounds.  
 
     
     
         21 . The distillation according to  claim 20  wherein said mixture comprises hydrocarbons.  
     
     
         22 . A process for the production of methanol comprising the steps of: 
 (a) feeding solvent containing a methanol catalyst to a column containing a liquid continuous phase;    (b) feeding a gas containing carbon monoxide, carbon dioxide and hydrogen to said column below the catalyst containing solvent feed at a rate such that the gas is flowing upward in said column at a rate equal greater than 50% of jet flood to less than 100% of jet flood;    (c) withdrawing methanol from said column as overheads; and    (d) withdrawing catalyst containing solvent from said column as bottoms.    
     
     
         19 . The process according to  claim 18  wherein said catalyst comprises copper and zinc supported on alumina.  
     
     
         23 . The process according to  claim 18  where a portion of said solvent is vaporized and removed as overheads.  
     
     
         24 . The process according to  claim 20  wherein all of said vaporized solvent in said overheads is condensed and returned to said column as reflux.  
     
     
         25 . The process according to  claim 18  wherein spent catalyst is removed in a slip stream and makeup catalyst is added as needed.