Specific Electricity Consumption optimization of Raw Grinding Workshop in a Moroccan Cement Plant

The cement plants are the most energy intensive industry. The objective of this study is to optimize the specific electricity consumption of the raw mill workshop for Moroccan cement plant while ensuring the adequate product quality and mill stability. After description of the manufacturing process of clinker and cement three parameters those are mill throughput, hydraulic pressure and mill outlet temperature were retained to test their effect on the mill specific electricity consumption (SECmill) and mill vibration (V). Response surface methodology with the composite central design was followed to analyze and optimize the process. Two models predicting the SECmill and V in function of the three parameters studied were developed, respectively. Basing on the statistical results, these models predict the optimum values of the SECmill and V, with satisfactory error. The optimal configuration to minimize the workshop's specific power consumption was obtained for a maximum mill outlet temperature of 112.5°C, a maximum capacity of mill feed throughput and an average mill rollers hydraulic pressure of 133 bar. The predicted vibration corresponding to this configuration was well below the maximum thresholds that the mill can handle.