Dynamic Behavior of Closed Grinding Systems and Model Uncertainty

The object of the present study is to investigate the dynamic of closed circuit cement mills. The model that has been developed, involving integral part and a first order filter, is based exclusively on industrial data sets of three cement mills routine operation, collected in a up to one year period. The model parameters uncertainty is also assessed varying from 28% to 35% as the gain is concerning and 33% to 40% as regards the time delay. The grinding of different cement types in the same cement mill is determined as a significant source of model uncertainty. The described system identification can be utilized for the effective tuning of a robust controller regulating the cement mills operation.