(170d) An Investigation into the Performance of an Industrial-Scale Roll Mill

Jacob, K., University of Michigan
Koch, J. F., The Dow Chemical Company
Freireich, B., Particulate Solid Research, Inc.
Kodam, M., The Dow Chemical Company
Prediction of mill performance is a difficult task. In order to predict the performance of a roll mill, it is useful to determine the selection and breakage functions of a mill for a particular bulk solid as a function of mill parameters such as roll gap, roll differential speed, and mill feed rate. This enables modeling of the grinding circuit under changing mill and feed conditions and estimation of the product particle size. In this investigation, a production-sized roll mill was fed tightly sized fractions of particles which yielded the selection function and daughter particle size distribution (PSD) directly. In addition, the mill was also fed a polydisperse PSD in order to investigate how well the exit PSD was modelled using the data from the tightly sized fractions. Lastly, the experimental breakage matrix was compared with the predictions of several breakage matrix models.