Aspects of Modeling Coal Enrichment Processes by Gravity Methods

This study examines the challenges associated with processing hard coal, with a specific focus on gravitational enrichment methods and the utilization of jigs for coal separation. The research involves the simulation and modeling of physical property distributions and the analysis of both the feed density distribution and the characteristics of the enrichment products. Findings indicate that the resultant density distributions are influenced not only by the gravitational enrichment process but also by the preceding procedures and the inherent properties of the coal, such as particle size, sulfur content, and ash content, all of which significantly affect the quality of the outcomes. In modeling and optimization efforts, the study emphasizes approximating grain density using selected statistical distributions—specifically, the Weibull, logistic, and Gaudin–Schuhmann–Andreyev (GSA) distributions—before and after the enrichment process. Statistical analyses demonstrate that the GSA distribution most accurately fits the grain density distribution in the feed, while the Weibull distribution provides the best approximation for the separation products. The quality of these approximations was assessed using the coefficient of determination (R 2 ) and the Mean Squared Error (MSE). The best quality of approximation for feed was obtained by means of the GSA distribution function, and the MSE was approximately 3.1 for two analyzed values of feed flow rates. In the case of concentrates and tailings, the results are not unequivocal.