Title:
Improving the Performance of Enzymes in Hydrolysis of High Solids Paper Pulp delivered from MSW
Author(s):
Puri, D.J., Heaven, S., Banks, C.J.
Document(s):
Paper
Abstract:
The research aimed at improving the overall conversion efficiency of the CTec® family of enzymes by identifying factors that lead to inhibition and seeking methods to overcome these through process modification and manipulation. Pulp derived from municipal solid waste was processed in an industrial-scale washing plant and diluted to a total solids content of 18.5% TS before single-stage enzyme hydrolysis which resulted in a maximum glucan conversion of 68%. It was found that two-stage hydrolysis could give higher conversion if sugar inhibition was removed by an intermediate fermentation step between hydrolysis stages, resulting in a 9% increase in glucan conversion. This system, however, was not as effective as direct removal of the sugar products, including xylose, by washing of the residual pulp at pH 5. This allowed reactivation of the pulp-bound enzymes and improved the water availability resulting in a 14% increase in conversion compared to the no wash control. Inhibition of enzyme activity could be alleviated by replenishment of ß-glucosidase which was shown to be washed out with the sugar solution resulting in an overall glucan conversion of 88% (20% increase over the control). Furthermore the addition of both primary and secondary hydrolysates resulted in a glucose solution with close to 8% sugars which is an ideal starting point for fermentation. This is a significant improvement over a single-step process.
Keywords:
bioethanol, enzymatic hydrolysis, lignocellulose, municipal solid waste (MSW)
Topic:
R&D on Processes for Solid, Liquid and Gaseous Fuels from Biomass
Subtopic:
Bioethanol production and sugar release from lignocellulosic biomass
Event:
21st European Biomass Conference and Exhibition
Session:
3DO.8.5
Pages:
1382 - 1386
ISBN:
978-88-89407-53-0
Paper DOI:
10.5071/21stEUBCE2013-3DO.8.5
Price:
FREE
