Abstract: Described herein is an operation-control device adapted for controlling operation of a disperser and including an input unit for receiving, from sensing devices, state-values (V1, V2, V3) of at least two different physical entities and/or operational states of the disperser, such as temperature, pressure, etc. A functional-correlation storage unit is configured to store a functional correlation model including correlations of state-values of subsets of physical entities and/or operational states of the mill and indicative of a predetermined plausibility condition associated to a respective correlation. A plausibility-checking unit is configured to determine a flag to the plausibility condition and to provide a corresponding status signal.