Prediction of power of a vibration rod mill during cellulose decrystallization processing by DEM

The crystallinity index of cellulose decrystallized with a vibration rod mill was well correlated with input energy of the vibration rod mill. In order to predict the energy, rod behavior was simulated by discrete element method (DEM). Decrystallization of cellulose was performed using a vibration rod mill to increase the reactivity. The decrystallization speed increased with an increase in the number of rods and the crystallinity index of cellulose after pulverization can be uniquely identified by the input energy [kWh/kg], which is actual power times pulverization time divided by cellulose mass charged into the vibration rod mill. Therefore, the actual power of the vibration rod mill was calculated using DEM simulation, wherein rods were constructed by connecting spherical particles using the multi-sphere method. The coefficients of friction and restitution were determined based on the movement of the rod in the mill cylinder from the experiments. The power calculated agrees with the actual power. This study suggests that the power of the vibration rod mill can be predicted using DEM and that the crystallinity index can be predicted without experimentation.