Measurement accuracy selection for designing observers of metallurgical plant performances

Process optimization requires an accurate on-line estimation of performance indicators such as the net revenue. Measurements coupled to mass (or energy) conservation submodels are frequently used in metallurgical plants for the reconciliation of models and raw data, followed by an estimation of the plant performance. The success of real-time plant optimisation is strongly dependent on the quality of the performance index estimation, which is directly related to the measurement strategy and raw data accuracy. A method is proposed to define the required variances of the various measurements to ensure an accurate estimation of the plant performance. The cost of having low raw data variance increases with the quality and the frequency of the maintenance of the measurement procedures and equipments, factors that are considered in the proposed design method.