Waste coal gangue was utilized for the fabrication of strength glass-ceramics for environmental management. The optimal utilization rate of coal gangue is 55 wt.% when the utilization rate of another mineral material bauxite is 35 wt.%. The mullite showing high strength is the main crystal phase in the sintered glass-ceramics. The effect of various processing parameters on the microstructure and mechanical performances of the sintered glass-ceramics was systematically studied. Mineralization agent BaCO₃ and MnCO₃ resulted in remarkable enhancement of the mechanical properties of the sintered glass-ceramics. The strength of 148.36-156.12 MPa, water absorption of 0.17-0.02%, and a density of 2.66-2.68 g/cm³ were achieved for the sintered glass-ceramics. The process of forming and sintering also showed a remarkable effect on the microstructural and mechanical properties. By optimization experiments, optimal processing parameters were also determined.

Keywords: Coal gangue; Glass-ceramics, Waste management, Maximal utilization ratio, Process optimization, Mechanics property