Wednesday, May 7, 2008 - 4:00 PM
11-05

The IBUS process - Large scale SSF at high dry matter content (>25% WIS)

Mai Østergaard Petersen, DONG Energy, Kraftværksvej 53, DK-7000 Fredericia, Denmark and Jan Larsen Sr., Inbicon, Klippehagevej 22, DK-7000 Fredericia, Denmark.

In the IBUS process all process steps are carried out at high dry matter content thus minimising water and energy consumption. This gives rise to special challenges, especially in the enzymatic hydrolysis and SSF when working with dry matter contents above 25% (water insoluble solids). This is due to difficulties with agitation of the initially very viscous mash. Earlier published experiments with SSF at high dry matter content have shown that the yield of ethanol decreases as the dry matter content increases (1). This is most likely caused by problems with mass transfer caused by high viscosity.
The experiments presented here compare results at high and low dry matter content showing that it is possible to reach the same cellulose conversion (ethanol yield) at high and low dry matter content.

 1. Jørgensen, H., et al., Liquefaction of lignocellulose at high-solids concentrations. Biotechnology and  Bioengineering, 2007. 96(5): p. 862-870.