Control and optimization of a cement rotary kiln: A model predictive control approach

In this paper, a Model Predictive Control strategy is used to stabilize a temperature profile along a cement rotary kiln minimizing fuel specific consumption. The adopted system architecture is composed of two different optimization layers that interact in order to improve control performances and to meet possibly variable economic goals. The developed cooperation logic between the two layers that takes into account priority ranking of controlled variables constraints has been proven to improve system performances. The developed MPC system has been implemented on a cement plant and its performances are compared to the performances of the previous system based on standard PID controllers. The results are very satisfactory in terms of economic benefits and of minimization of environmental noxious emissions.