Processes and systems for alcohol production and recovery

Abstract

The present invention relates to processes for recovering butanol produced in a fermentative process using, for example, an ethanol production plant which has been reversibly-retrofitted for butanol production, that is, the ethanol production plant may be converted for butanol production, but can also revert to an ethanol production. The present invention also relates to processes for recovering butanol produced in a fermentative process in a butanol production plant that may be converted to ethanol production plant.

1 - 92 . (canceled) 
     
     
         93 . A process for producing one or more product alcohols using a reversibly-retrofitted production plant, comprising:
 (a) providing a reversibly-retrofitted production plant comprising one or more fermentors for the production of one or more product alcohols, wherein at least one fermentor has been retrofitted for the production of one or more product alcohols;   (b) providing an aqueous feedstream obtained from biomass, the aqueous feedstream comprising water and fermentable sugar;   (c) contacting the aqueous feedstream with a fermentation broth in the at least one fermentor, the fermentation broth comprising a microorganism capable of producing one or more product alcohols;   (d) fermenting the fermentable sugar in the at least one fermentor, wherein the microorganism produces one or more product alcohols, whereby the fermentation broth comprises one or more product alcohols;   (e) separating the fermentation broth comprising the one or more product alcohols to produce a product alcohol-rich stream and product alcohol-lean stream; and   (f) recovering the one or more product alcohols from the product alcohol-rich stream.   
     
     
         94 . The process of  claim 93 , further comprising recovering the one or more product alcohols from the product alcohol-lean stream of step (e). 
     
     
         95 . The process of  claim 94 , wherein the one or more product alcohols are recovered from the product alcohol-lean stream utilizing existing distillation equipment. 
     
     
         96 . The process of  claim 95 , wherein the existing distillation equipment comprises a beer column, a side stripper, and a rectifier. 
     
     
         97 . The process of  claim 94 , wherein the one or more product alcohols are recovered from the product alcohol-lean stream utilizing retrofitted distillation equipment. 
     
     
         98 . The process of  claim 93 , further comprising recovering the one or more fusel alcohols from the product alcohol-lean stream of step (e). 
     
     
         99 . The process of  claim 98 , wherein the one or more fusel alcohols are recovered from the product alcohol-lean stream utilizing existing distillation equipment. 
     
     
         100 . The process of  claim 99 , wherein the existing distillation equipment comprises a beer column, a side stripper, and a rectifier. 
     
     
         101 . The process of  claim 98 , wherein the one or more fusel alcohols are recovered from the product alcohol-lean stream utilizing retrofitted distillation equipment. 
     
     
         102 . The process of  claim 93 , wherein the reversibly-retrofitted production plant further comprises one or more pre-flash units, one or more flash units, or a combination thereof. 
     
     
         103 . The process of  claim 93 , wherein step (e) separating the fermentation broth including the one or more product alcohols comprises:
 (I) at least partially vaporizing the fermentation broth forming a vapor stream comprising the one or more product alcohols; and   (II) recovering the one or more product alcohols.   
     
     
         104 . The process of  claim 103 , further comprising:
 (i) condensing the vapor stream comprising the one or more product alcohols to form a liquid stream and a residual vapor stream;   (ii) separating the liquid stream forming an aqueous phase and organic phase comprising one or more product alcohols; and   (iii) recovering the one or more product alcohols from the organic phase.   
     
     
         105 . The process of  claim 93 , wherein step (e) separating the fermentation broth including the one or more product alcohols comprises:
 (I) degassing the fermentation broth;   (II) at least partially vaporizing the degassed fermentation broth forming a vapor stream comprising the one or more product alcohols; and   (III) recovering the one or more product alcohols.   
     
     
         106 . The process of  claim 105 , further comprising
 (i) condensing the vapor stream comprising the one or more product alcohols to form a liquid stream and a residual vapor stream;   (ii) separating the liquid stream forming an aqueous phase and organic phase comprising one or more product alcohols; and   (iii) recovering one or more product alcohols from the organic phase.   
     
     
         107 . The process of  claim 105 , wherein the fermentation broth is degassed to remove at least a portion of non-condensible gases. 
     
     
         108 . The process of  claim 105 , wherein the vaporization of step (II) is conducted at a lower pressure than the degassing of step (I). 
     
     
         109 . The process of  claim 93 , wherein step (e) separating the fermentation broth including the one or more product alcohols comprises:
 (i) contacting the fermentation broth with an extractant to form a biphasic mixture comprising an aqueous phase and an organic phase, wherein the one or more product alcohols partition into the organic phase to form a product alcohol-containing organic phase;   (ii) separating the product alcohol-containing organic phase and the aqueous phase, the aqueous phase comprising the product alcohol-lean stream; and   (iii) recovering the one or more product alcohols from the product alcohol-containing organic phase.   
     
     
         110 . The process of  claim 109 , wherein the product alcohol-containing organic phase is separated from the aqueous phase by siphoning, decantation, centrifugation, mixer-settler, gravity settler, membrane-assisted phase splitting or a combination thereof. 
     
     
         111 . The process of  claim 109 , wherein the extractant is fatty alcohols, fatty acids, fatty esters, fatty aldehydes, fatty amides, triglycerides, monoalkyl phosphates, dialkyl phosphates, trialkyl phosphates, or a combination thereof. 
     
     
         112 . The process of  claim 93 , wherein the one or more product alcohols is ethanol, butanol, or a combination thereof. 
     
     
         113 . The process of  claim 94 , wherein the one or more product alcohols is ethanol, butanol, or a combination thereof. 
     
     
         114 . The process of  claim 95 , wherein the one or more product alcohols is ethanol, butanol, or a combination thereof. 
     
     
         115 . The process of  claim 97 , wherein the one or more product alcohols is ethanol, butanol, or a combination thereof. 
     
     
         116 . The process of  claim 103 , wherein the one or more product alcohols is ethanol, butanol, or a combination thereof. 
     
     
         117 . The process of  claim 104 , wherein the one or more product alcohols is ethanol, butanol, or a combination thereof. 
     
     
         118 . The process of  claim 105 , wherein the one or more product alcohols is ethanol, butanol, or a combination thereof. 
     
     
         119 . The process of  claim 106 , wherein the one or more product alcohols is ethanol, butanol, or a combination thereof. 
     
     
         120 . The process of  claim 109 , wherein the one or more product alcohols is ethanol, butanol, or a combination thereof. 
     
     
         121 . The process of  claim 110 , wherein the one or more product alcohols is ethanol, butanol, or a combination thereof. 
     
     
         122 . The process of  claim 111 , wherein the one or more product alcohols is ethanol, butanol, or a combination thereof.