Predicting washability using a regression of ash content with controlled rock to coal mix ratio specimen used for calibration

Accurate information on coal washability characteristics is crucial for optimizing beneficiation processes. This study investigates the use of dual-energy X-ray transmission (DE-XRT) in predicting ash content and specific gravity (S.G.) by employing a structured calibration approach. A total of 36 coal samples from a British Columbia mine were analyzed using DE-XRT, S.G. measurements, and ash analysis. A controlled calibration method was developed by systematically varying rock-coal (rock-ash forming minerals) ratios to establish reliable DE-XRT response trends. Results demonstrated strong correlations between DE-XRT-derived relative density and rock mix ratios, confirming its capability in estimating coal quality. The generated washability curves closely followed traditional sink-and-float results, particularly at higher ash contents, validating DE-XRT's potential in coal sorting. These findings highlight DE-XRT as a viable tool for real-time coal quality assessment during its beneficiation. Future work should focus on refining calibration techniques and improving detection in extreme density ranges to enhance prediction accuracy and sorting efficiency.