Robust control of a flash dryer plant

In this paper, model-based control is applied to an industrial plant, a flash dryer for starch, with the aim of improving the robustness of the regulation and to find a remedy to some undesired features of its behavior. Since on-line measures of the output variable of the process, the starch moisture, are not available, a classic regulation for the process is not possible and the desired moisture value has to be fixed by the operator setting some other parameters by means of empirical rules. An observer is implemented, to estimate the moisture from the other process variables. No a priori knowledge on the process being available, a black-box approach is chosen. The obtained model is then used for an open-loop regulation of the starch moisture and its robustness is tested.