Upgrading and quality-classification of inertinite-rich coal from Western China based on maceral separation

Increasing energy demand and high environmental pressure are calling for grading, quality-based classification and effective utilization of coal in China. Using fine classification and multistage pulverization liberation techniques, a typical inertinite-rich coal was used to study the migration characteristics of ash content, sulfur content and macerals of the classifier products. The results showed that the vitrinite and the inertinite contents obtained using fine classification technique reached the maximum of 61.5% and 73.3%, respectively, with enrichment efficiencies of 16.6% and 55.3%, respectively. In contrast, the maximum vitrinite and inertinite contents treated with the multistage pulverization liberation technique reached 58.9% and 82.8%, respectively, with enrichment efficiencies of 11.8% and 75.4%, respectively. A calculation model and a process model for the pulverization liberation of coal maceral were proposed. The maceral separation techniques developed in this study showed outstanding quality improvement and quality-based classification effects. (C) 2020 Elsevier B.V. All rights reserved.