Biological Systems Engineering, Department of


First Advisor

Deepak Keshwani

Date of this Version


Document Type



Emanuel, Ellen. "Techno-economic Implications of Fed-batch Enzymatic Hydrolysis" (2017).


A THESIS Presented to the Faculty of The Graduate College at the University of Nebraska In Partial Fulfillment of Requirements For the Degree of Master of Science, Major: Agricultural and Biological Systems Engineering, Under the Supervision of Professor Deepak R. Keshwani. Lincoln, Nebraska: November, 2017.

Copyright (c) 2017 Ellen Emanuel


As ethanol production continues to increase in the United States, cellulosic ethanol continues to gain traction as a viable option for meeting ethanol demands. In this work, a literature review of techno-economic analyses for cellulosic ethanol was conducted. It was found that pretreatment methods greatly affect the ethanol production costs. There is a lack of techno-economic data comparing a batch enzymatic hydrolysis to a fed-batch enzymatic hydrolysis for a separate hydrolysis and fermentation production process. Consequently, a techno-economic analysis comparing cellulosic ethanol production using batch versus fed-batch enzymatic hydrolysis was conducted. SuperPro Designer software (Intelligen, Scotch Plains, New Jersey), a process simulation tool, was used to simulate ethanol production. The simulation revealed that the biggest difference between batch and fed-batch hydrolysis was facilities costs, which decreased by 41% when using fed-batch enzymatic hydrolysis. A sensitivity analysis revealed that our ethanol production costs were most sensitive to the cost of the corn stover biomass. In general our results support the idea that fed-batch enzymatic hydrolysis does improve the techno-economics of cellulosic ethanol production, even if the improvements came in process steps we did not expect.

Advisor: Deepak R. Keshwani

EtOH9_5 - CB - SPD base case.spf (834 kB)
SuperPro Designer file for batch hydrolysis base case

EtOH9_5 - CFB - SPD base.spf (831 kB)
SuperPro Designer file for fed-batch hydrolysis base case