Monday, May 2, 2011
Grand Ballroom C-D, 2nd fl (Sheraton Seattle)
A semi-continuous pretreatment method was tested at low severity conditions and compared with the batch treatments. The semi-continuous pretreatment method, initiated with 10% solids concentration, was performed by removing some of the aqueous phase along with released xylan after each pretreatment and returning the separated solids along with a new batch of biomass at 10% solids concentration. After 3 such treatments, the solid obtained from the semi-continuous treatment was enzymatically hydrolyzed, and the total sugar released from the semi-continuous treatment was compared with that obtained after pretreatment at 30% solids concentration in a traditional batch reactor. Due to additional pretreatment on the recycled biomass, glucose release during pretreatment and enzymatic hydrolysis with low enzyme loadings was improved in the semi-continuous pretreatment process. This process provides the ability to handle higher solids concentrations with less xylan and total sugar loss in a batch reactor, along with a lower enzyme requirement during enzymatic hydrolysis.