title: Economic evaluation of preconcentration in production of ethanol from dilute sugar solutions.
abstract: The economic feasibility of preconcentrating dilute sugar solutions prior to fermentation is investigated. Two methods, evaporation and reverse osmosis, are compared. A computer program to determine the optimal preconcentration conditions for glucose solutions of 1.5-16 wt% has been developed. It was used to compute the fractional cost for labor and maintenance, preconcentration, fermentation, and distillation. Preconcentration with evaporation resulted in a higher total cost, compared with no preconcentration, for all cases studied, although a six-effect unit was used. Reverse osmosis was found to be economically feasible for preconcentration to about 5-10 wt % depending on the concentration of the feed.
authors.affiliation: Department of Chemical Engineering 1, University of Lund, P.O. Box 124, S-221 00 Lund, Sweden.
authors.forename: G
authors.initials: G
authors.lastname: Zacchi
authors.forename: A
authors.initials: A
authors.lastname: Axelsson