Abstract:  Aiming at the process complexity and high energy consumption problems of cement clinker storage and transfer system based on belt conveyor, the energy efficiency of the entire systems was researched using optimization methodology. First of all, a complex storage and transfer system of cement clinker constituted by belt conveyors was analyzed from a process decomposition perspective. Then, optimal control technology was employed to build optimal scheduling strategies for the belt conveyors of the storage and transfer systems, where the feed rates of conveyors were taken as controlled variables. Time-of-use tariff, production prediction of the cement plants, and various constraints such as silo storages were also considered in these optimal scheduling strategies. Finally, the simulation of the proposed optimal scheduling strategies was conducted; and optimal horizons were studied in terms of their effect on energy efficiency. The results indicate that under the conditions with constant predictions and variable predictions, the optimal scheduling strategies can save energy and achieve remarkable cost savings of cement clinker storage and transfer system based on belt conveyor at the same time. When the prediction time is greater than or equal to 4 h, the proposed optimal scheduling strategies can get great profit. The lower requirement for prediction time span relieves the difficulty of field application; thus it makes the strategies more applicable.

Key words:  belt conveyors; storage and transfer system; optimal scheduling; cement clinker