Analysis of the EAF operation by process modelling

Process modelling is often used for the observation and control of the EAF process. Online process models allow the calculation of values incapable of measurement like the actual liquid and solid steel mass in the furnace or the permanent monitoring of the actual mean temperature of the liquid steel. An additional benefit comes from offline process simulations allowing an affordable scientific investigation of the EAF operation. The process model can be regarded as a software replacement of the real furnace. Since a specific process model may predict not all relevant information and not all model parameters are known with a sufficient accuracy, the process models need to be validated. For studying the fundamental behaviour of the process and its optimization options, the model has to be as simple as possible – but not simpler. By using a multi-zone meltdown model [1], the EAF operation is analysed on a theoretical basis. An exemplary model analysis is provided. The process modelling tools are used to demonstrate how to determine optimum DRI feeding or scrap charging procedures. The model predictive control (MPC) approach for continuous DRI feeding is found to be as efficient as global process optimizations (in theory).