Biofuel subsidies from the Canadian government were officially phased out in 2017, which has had a significant effect on the biofuel industry in Canada. Specifically, this change will force biofuel producers to adopt novel technologies that promote more cost-efficient biofuel production, or that result in co-production of high-value products, transforming ethanol plants into multiple-product biorefineries. This project aims to advance research for both of these areas and involves several industrial and government partners that are interested in eventual commercialization of such strategies.
The Bressler lab will explore several byproduct streams generated during industrial processing of macroalgae, crops, and woody materials. This will involve comprehensive compositional analyses to identify molecules/compounds that have direct or indirect commercial value, as well as exploring processing strategies, particularly enzyme treatment, which can facilitate downstream fractionation of these molecules/compounds into separate co-product streams. Finally, following separation, the Bressler lab will examine processing strategies that can be employed to generate value-added products from these co-product streams. As an example of one of the ongoing studies in the lab, the Bressler lab is examining the enzymatic digestion of hardwood kraft pulp to generate a sugar stream for fermentation platforms, as well as a solid residue that is more efficiently converted to cellulose nanocrystals (CNCs), a lightweight and extremely strong nanomaterial that currently sells for $1000 per kilogram.
In addition, the Bressler lab, in collaboration with Prof. Dominic Sauvageau, is examining the incorporation of a self-cycling fermentation strategy for cellulosic ethanol production. Recent data have provided bench-scale proof-of-concept that a cycling strategy could be applied to cellulosic ethanol production, resulting in increased productivity (amount of ethanol produced per year). Based on these preliminary results, the Bressler and Sauvageau labs have developed a 5-L self-cycling fermentation system that will be used to optimize ethanol production from a wide variety of feedstocks.
The identification of by-product streams that can be used as feedstock and co-product generation strategies, combined with the development of novel fermentation technologies that can be applied at commercial scale, will have significant and beneficial outcomes for the cellulosic ethanol industry.