Biomass fermentation

Since fermentation takes place in a dilute aqueous solution, the reaction continues until the alcohol concentration approaches about 14%. At higher concentrations, the process becomes self-inhibitory. By-products from starch fermentation to ethanol can include higher-molecular-weight alcohols, glycerine, and ethers. Usually no more than 10% starch is converted to these compounds. Atmospheric distillation, vacuum distillation, and membrane separation techniques can be used to recover ethanol from the final fermented product. The distillate bottoms, called stillage, are recovered as a by-product for animal feed. A biomass fermentation flow diagram is provided in FIGURE 12-2. 

Such a country is Brazil. Burdened under a massive balance of payments deficit due mainly to a lack of any petroleum reserves, Brazilians have been looking to other fuel sources for some time. Already some Brazilian gasoline contains a substantial percentage of ethanol derived from biomass fermentation (principally sugar cane bagasse and molasses). 

Recovery of volatile organic flavor compounds (ethyl acetate, EA ethyl propionate, EP ethyl butyrate, EB) Product recovery from biomass fermentation processes... 

Vane LM. A review of pervaporation for product recovery from biomass fermentation processes. J. Chem. Tech. Biotech. 2005 80 603-629. 

The OMBRE approach is applied to a biomass fermentation model [1], which, assuming Monod-type kinetics for biomass growth and substrate consumption, is described by the following DAEs set ... 

Ethanol-from-biomass fermentation is an example of product inhibition, while high fermentable carbohydrate concentrations also can become inhibitive. Aiba and Shoda developed a mathematical model for the anaerobic fermentation, where nine constants are required to describe the model,... 

In a recent study, it was found that a high initial cell concentration increased the rate of xylose utilization and ethanol formation in P. stipitis [20]. Results from our previous work [20] and this work suggest that there are two options available for using P. stipitis for biomass fermentation. The first option is to operate at suboptimal conditions of low aeration where adaptation or a high initial cell concentration improves the speed of the fermentation. The second option is to operate at optimal fermentation conditions where microaerophilic conditions need to be maintained. Choosing between these two options under industrial conditions will require cost benefit analysis to determine the most viable option. 

Spano, L. "Revised Economic Analysis of Cellulose Process Technology", Fuels From Biomass Fermentation Newsletter Rensselaer Polytechnic Institute, Troy, N. Y., July 1978, Item 4, p 9. 

PLA is primarily considered for medical implants and drug delivery, but broader applications in packaging and consumer goods are also targeted. An attractive feature of this material is the relatively low cost of the monomer, lactic acid, which can be derived from biomass (fermentation), coal, petroleum, or natural gas. 

Product recovery from biomass fermentation processes... 

Rabaey, K., Lissens, G., Verstraete, W. (2005). Microbial fuel cells performances and perspectives. In P. Lens, P. Westerman, A. Haberbauer, A. Moreno (Eds.), Biofuels for fuel cells Renewable energy from biomass fermentation. London IWA Publishing. 

Butanol (C4H,oO) Glucose, corn, waste biomass Fermentation of organics Fermentation... 

Butyric acid can be conventionally produced by oxidation of butyraldehyde. A variety of anaerobic bacteria are able to produce butyric acid as the major end product during fermentation process. Nevertheless, Clostridium species have been used preferentially for butyric acid production because of their plain medium requirements and comparatively high product yields. The major focus in current research is on C. butyricum with a pH range between 5.0 and 7.0. But optimisatirHi of C. tyrobutyricum within green biomass fermentation could be very worthwhile because of the fact that C. tyrobutyricum is able to ferment lactate produced by Lactobacteriaceae. Furthermore, C. tyrobutyricum tolerates low pH values down to 4.2 which could be an advantage in big-scale implementation. 

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