Process and Systems for the Fermentative Production of Alcohols

Abstract

The present invention relates to the fermentative production of alcohols including ethanol and butanol, and processes for improving alcohol fermentation employing in situ product removal methods.

1 - 21 . (canceled) 
     
     
         22 . A method for recovering a product alcohol from a fermentation broth comprising
 providing a fermentation broth comprising a microorganism, wherein the microorganism produces product alcohol in a fermentor;   providing a feedstock slurry comprising fermentable carbon source, undissolved solids, oil, and water;   separating the feedstock slurry whereby (i) an aqueous solution comprising fermentable carbon source, (ii) a wet cake comprising solids, and (iii) an oil are formed;   adding the aqueous solution to the fermentation broth;   contacting the fermentation broth with at least one extractant; and   recovering the product alcohol.   
     
     
         23 . The method of  claim 22 , wherein the oil is hydrolyzed to form fatty acids. 
     
     
         24 . The method of  claim 23 , wherein the fermentation broth is contacted with the fatty acids. 
     
     
         25 . The method of  claim 23 , wherein the oil is hydrolyzed by an enzyme. 
     
     
         26 . The method of  claim 25 , wherein the enzyme is one or more lipases or phospholipases. 
     
     
         27 . The method of  claim 22 , wherein the feedstock slurry is generated by hydrolysis of feedstock. 
     
     
         28 . The method of  claim 27 , wherein feedstock is selected from rye, wheat, corn, cane, barley, cellulosic or lignocellulosic material, or combinations thereof. 
     
     
         29 . The method of  claim 22 , wherein the feedstock slurry is separated by decanter bowl centrifugation, three-phase centrifugation, disk stack centrifugation, filtering centrifugation, decanter centrifugation, filtration, vacuum filtration, beltfilter, pressure filtration, filtration using a screen, screen separation, grating, porous grating, flotation, hydroclone, filter press, screwpress, gravity settler, vortex separator, or combination thereof. 
     
     
         30 . The method of  claim 22 , wherein separating the feedstock is a single step process. 
     
     
         31 . The method of  claim 22 , wherein the wet cake is combined with the aqueous solution. 
     
     
         32 . The method of  claim 22 , further comprising contacting the aqueous solution with a catalyst converting oil in the aqueous solution to fatty acids. 
     
     
         33 . The method of  claim 32 , wherein the aqueous solution and fatty acids are added to the fermentation broth. 
     
     
         34 . The method of  claim 32 , wherein the catalyst is deactivated. 
     
     
         35 . A system comprising
 one or more fermentors comprising:
 an inlet for receiving feedstock slurry; and 
 an outlet for discharging fermentation broth comprising product alcohol; and 
   one or more extractors comprising:
 a first inlet for receiving the fermentation broth; 
 a second inlet for receiving extractant; 
 a first outlet for discharging a lean fermentation broth; and 
 a second outlet for discharging a rich extractant. 
   
     
     
         36 . The system of  claim 35 , further comprising
 one or more liquefaction units;   one or more separation means; and   optionally one or more wash systems.   
     
     
         37 . The system of  claim 36 , wherein the separation means is selected from decanter bowl centrifugation, three-phase centrifugation, disk stack centrifugation, filtering centrifugation, decanter centrifugation, filtration, vacuum filtration, belt filter, pressure filtration, membrane filtration, filtration using a screen, screen separation, grating, porous grating, flotation, hydroclone, filter press, screwpress, gravity settler, vortex separator, and combinations thereof. 
     
     
         38 . The system of  claim 35 , wherein the system further comprises on-line measurement devices. 
     
     
         39 . The system of  claim 38 , wherein the on-line measurement devices are selected from particle size analyzers, Fourier transform infrared spectroscopes, near-infrared spectroscopes, Raman spectroscopes, high pressure liquid chromatography, viscometers, densitometers, tensiometers, droplet size analyzers, pH meters, dissolved oxygen probes, or combinations thereof.