Tuesday, April 30, 2013
Exhibit Hall
Woody biomass is particularly resistant to breakdown and must be size reduced to make pretreatment with steam, acid, or other chemicals that hydrolyze biomass to sugars effective. However, because mechanical size reduction of woody biomass can consume a significant amount of energy, it is important to understand how to minimize size reduction, while still realizing high sugar yields from the combined operations of pretreatment and enzymatic hydrolysis. Thus, this study focused on determining how sugar yields change with particle size. Downscaled composition analysis and enzymatic hydrolysis were applied to different sizes wood chips and powder of Populus tremuloides, and examined whether small size wood chips and powder can always have better pretreatment and have higher sugar release. However, it was found that above a certain pretreatment severity range large size wood chips could also result into higher enzymatic sugar yields, and the reduction in wood chip size is not always required, thus, saving in energy. Furthermore, models are also being developed to better understand the result, and figure out how heat and mass transfer affect pretreatment effectiveness and establish maximum dimensions to high sugar release.