On the unstable behavior of cement grinding circuits

The present work deals with new observations made on a grinding plant of CBR (Mons, Belgium), which reveal an unstable behavior of the process due to the classifier. In particular, the influence of the flow rate entering the classifier is highlighted. The dynamic simulator developed and validated in a previous study is extended to include a new model of first generation classifiers and now reproduces the instability. Practically, the instability makes this process difficult to control. A new control structure has been proposed, tested in simulation and its implementation on the plant offers more efficiency and robustness.