The effect of high solids loading in ethanol production integrated with a pulp mill
Journal article, 2016
In this paper, two ethanol processes integrated with a softwood pulp mill are compared with regard to their steam demand, process integration potential and profitability. The processes differ in the solids loading in the simultaneous saccharification and fermentation step and in the resulting ethanol concentration. The results show that a higher ethanol concentration does not necessarily lead to significant reductions in steam demand. Instead, it is demonstrated that the steam demand for distillation is highly dependent on the design of the distillation plant. Nevertheless, a higher solids loading (high gravity) can be beneficial for the treatment of the stillage from the distillation plant. A higher solids loading results either in a lower steam demand for evaporation of the stillage or possibly in a reduced demand for effluent treatment compared to a conventional solids loading process. While the results show that a higher ethanol concentration leads to advantages in energy costs and investment costs for the distillation plant, they also show that the potential benefits of a high-gravity process are offset by the expected decrease in ethanol yield, which leads to higher raw material costs. (C) 2016 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.
saccharification
pretreatment
wood
biomass
High gravity
Ethanol
enzymatic-hydrolysis
energy efficiency
Engineering
Biorefinery
softwood
Techno-economic assessment
Pinch analysis
simultaneous
lignocellulosic ethanol
Pulp mill
fermentation
corn stover
Author
Elin Svensson
Chalmers, Energy and Environment, Industrial Energy Systems and Technologies
Valeria Lundberg
Chalmers, Energy and Environment, Industrial Energy Systems and Technologies
M. Jansson
Innventia
Charilaos Xiros
Chalmers, Biology and Biological Engineering, Industrial Biotechnology
Thore Berntsson
Chalmers, Energy and Environment, Industrial Energy Systems and Technologies
Chemical Engineering Research and Design
0263-8762 (ISSN) 1744-3563 (eISSN)
Vol. 111 387-402Subject Categories (SSIF 2011)
Chemical Engineering
DOI
10.1016/j.cherd.2016.05.026