Effect of High-Temperature Calcination and Mechanically Ball-Milling on Coal-Gangue Reactivity

Raw kaolinite-coal-gangue is very stable and difficult to leach Al straightly without activation.Two methods,i.e high-temperature calcinations and mechanically ball-milling for kaolinite activation are systemically investigated.Results show that the reactivity of kaolinite-coal-gangue can be markedly (enhanced) by high-temperature calcination or mechanically ball-milling,and the maximum leaching ratio of Al is 75.31% and 88.17%,respectively.Application of calcining and mechanical milling together benefits the activation of coal gangue,and the best effect is achieved by ball-milling followed by calcining.