FLS PC-blend: a PC-based system for pile control and tactical production monitoring

At most modern cement plants and other mineral processing plants, the composition of the ground raw blend must be within certain limits to ensure proper performance of the subsequent process stages. This is achieved by analysing the current blend and adjusting the feeding rates of the individual blend components in accordance with the blend composition. The FLS-QCX system is an example of a control system developed for this purpose. It has now been applied worldwide in cement plants for a decade. Generally, the major blend components mined from a plant's own raw material deposits are stockpiled in buffer stores which may or may not be of the prehomogenizing type. If the material stream reclaimed from such piles shows great composition variation over short periods, all raw mill feeding devices must have a high capacity to allow the raw blend control system to perform the necessary adjustments. If on the other hand, the average pile composition varies considerably from pile to pile, all equipment from mine to mill must have sufficient capacity to respond to the blend control adjustments. In order to avoid peak capacities on a new plant or shortage of feeding capacity when running an existing one, it is necessary to maintain the composition of the buffer store piles within certain limits. This applies both to the total quantity of each pile, as well as the cross-sectional quantities reclaimed successively from the pile. The FLS Pc-Blend system has been developed primarily for that purpose and will be described