BESTFZ: CoRyFee - Cost Reduction in Yeast Fermentation for Commercial

The Swedish pretreatment/hydrolysis process of cellulosic biomass and the Danish pentose fermenting yeast technology complement each other and coupled with the Biorefinery Demonstration Plant in Sweden they together comprise the whole Chain leading to 2. generation bioethanol.

The needed amount of enzymes, yeast and energy drives up the operation expenses (OPEX) per produced unit for 2G bioethanol production and as more unit operations are needed to process cellulosic biomass into ethanol compared with a 1G process, a higher initial capital expenditure (CAPEX) is also needed.

Release of inhibiting substances and weak acids during cellulosic biomass pretreatment makes the fermentation step more challenging than in a 1G process. The challenge can be partially circumvented by eg. increasing the yeast amount and tank capacity or adding process units, however all solutions increase OPEX.

We will address the need for reduction of the overall production costs by reducing:

- CAPEX/OPEX by development of an aligned optimized combination of the hydrolysis and fermentation process running at the hydrolysis process pH in a continuous mode.

- Expenses for yeast purchase and propagation by developing an integrated onsite
propagation process based on biomass hydrolysate as feedstock and continuous yeast feed to the fermentation along with the substrate feed