Washability assessment of Indian coking coal for optimized beneficiation and sustainable utilization

Abstract

The characterization of coal is fundamental prerequisite for designing washing circuits and achieving optimal utilization of cleaned coal products. Unlike traditional approaches, this research employs a particle size-specific washability analysis, providing a novel approach to improving coal beneficiation processes. Using Indian coking coal as a case study, the research evaluates washability characteristics across various size fractions utilizing advanced washability parameters such as Optimum Degree of Washability (ODW), Washability Number (WN), Index of Washability (IW), and Near Gravity Material Index (NGMI). Results reveal that smaller particle sizes enhance washability, with consistent ODW values suggesting uniform characteristics across sizes. Variations in WN and IW imply that finer fractions exhibit greater cleaning potential, while NGMI highlights the challenges associated with washing these finer particles. Key findings include achieving low ash content (<18%) at a specific gravity of 1.65, rendering the coal suitable for metallurgical applications. The comparison of washability parameters provides a comprehensive understanding of coal suitability for beneficiation processes and its potential to yield low ash content in cleaned coal products. These insights are pivotal for optimizing coal beneficiation processes and promoting sustainable and efficient utilization of Indian coking coal in the metallurgical industry.