In this work, a metallurgical simulator, developed in a previous project, was implemented to complete the operation of a L-150 pilot Jameson flotation cell, available at the Process Control Laboratory. The cell was instrumented and its distributed control system includes the pulp to air ratio, the froth depth and the wash water flow rate controllers. A fraction of the tailings can be recycled in order to keep a constant flow rate to the downcomer, independently of the fresh feed flow rate. This hybrid system combines the real operating variables of the pilot plant (feed flow rate, air flow rate, froth depth, wash water flow rate, downcomer pressure and gas hold up) with virtual variables, characterizing the feed (solids per cent, particle size distribution by classes, grades of mineralogical species by classes). All these variables are fed to a simulator to predict the characteristics of the concentrate and tailings (mass flow rate, grades, particle size distribution). The expert control strategy developed is based on the maximization of the cell Cu recovery subject to the technical specifications of the produced concentrate are met. To achieve this, the quality of the concentrate and tailings, predicted by the metallurgical simulator, are monitored on line. The cell recovery is estimated when an on line steady state test is passed. The expert system modifies the set points of the distributed control system. The supervisory control includes two main routines: expert feedback control, acting whenever a steady state is reached, and expert feed forward control, to compensate for measured disturbances on the characteristics of the feed. Several cases for different feed conditions are discussed and evaluated.
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