(621cs) Effect of Milling on Whole Biomass Slow Pyrolysis

Authors: 
Kelley, M. D., Tennessee Technological University
Biernacki, J. J., Tennessee Technological University
Murillo, J. D., Tennessee Technological University

The effect of milling on slow pyrolysis kinetics of whole biomass was explored. Samples were milled using a high intensity ball mill for 2, 4 and 6 hrs. The resulting material was characterized using temperature controlled X-Ray diffraction (XRD), scanning electron microscopy (SEM), thermal gravimetric analysis (TGA) and dilatometry. Milled samples of microcrystalline cellulose, switchgrass (panicum virgatum L.) and tall fescue straw (festuca arundinacea) were prepared. The overall project endeavors to characterize the effect of milling on biomass properties including particle size, contamination level, pyrolysis rates, crystallinity, char and gas formation and shrinkage. High intensity milling has a profound effect on degree of crystallinity. Even short milling times reduce the degree of crystallinity. Rates of hydration are likewise altered as measured by TGA, dramatically reducing the pyrolysis onset temperature and temperature of maximum decomposition rate.