Countercurrent saccharification of lime-pretreated corn stover - Part 1

Using the sugar platform, enzymes are a major cost contributor in biofuel production. Conventionally, enzymatic saccharification is performed in batch. To more efficiently use enzymes, a new continuous countercurrent method is explored. Pseudo-continuous countercurrent saccharification was performed on lime-pretreated corn stover at enzyme loadings of 1 mg CTec3/g dry biomass and (1 mg CTec3 + 1 mg HTec3)/g dry biomass and the results were compared with batch. To achieve the same glucan conversion as compared to batch, countercurrent saccharification reduced enzyme loading by 1.6 and 1.4 times at 1 mg protein/g biomass and 2 mg protein/g biomass, respectively. In batch saccharification, the effect of hemicellulase addition was investigated. In countercurrent saccharification, as compared to only 1 mg CTec3/g biomass loading, adding 1 mg HTec3/g biomass increased glucose and xylose yields by 6% and 12%, respectively. The effect of product sugars on enzyme inhibition was studied in batch saccharification.