In the first version of the Inbicon technology, only the C6 sugars were converted to ethanol, while the main part of the C5 sugars ended up in a molasses that could be used for feed or as biogas booster. The lignin is recovered, and used as an excellent solid biofuel. Now, the Inbicon technology has been developed so that both the C5 and the C6 sugars can be converted to ethanol.
The Inbicon technology is based on a one stage steam pretreatment, normally followed by solid/liquid separation and enzymatic hydrolysis. The solid fraction is treated enzymatically at high dry matter. The liquid fraction, containing the main part of the C5 sugars, can be bypassed the hydrolysis. If this is the case they will re-enter in the end of the hydrolysis where the C5 sugars, present as oligomers, are effectively hydrolysed. After this step the substrate is ready for fermentation.
Inbicon has now worked for a few years to identify and test C6/C5 yeasts together with yeast developers/suppliers, and tested performance successfully in large scale. The present presentation will give an impression of the work.