Energy saving and environmental impact decreasing in a walking beam reheating furnace

Abstract

In this work, an Advanced Process Control system aimed at the control and the optimization of a walking beam billets reheating furnace has been designed. In particular, a two-layer linear Model Predictive Control strategy has been adopted. A billets reheating first principles model has been formulated, in order to obtain accurate relationships between furnace zones temperature and billets temperature. To model the effect of the fuel flow rates on the furnace zone temperature, a black-box approach has been adopted. The cooperation between the control architecture and several supervision modules assures a flexible and resilient control, capable to cope with the most critical situations. Simulation tests and real plant results have demonstrated the soundness and the reliability of the proposed approach. With respect to the previous control system, manually operated by plant operators, the designed Advanced Process Control system allows the process to be maintained closer to its variables operating limits. In this way, energy saving and environmental impact decreasing have been obtained.