Low‐temperature sintering of ceramic proppants by adding solid wastes

Low‐density bauxite‐based ceramic proppants were prepared at sintering temperatures below 1300°C by adding solid wastes coal gangue and magnesium slag. The addition of solid wastes greatly decreases sintering temperature and preparation cost. The density and strength of ceramic proppants were tested according to the standard, and the morphology and phase composition were examined by scanning electron microscopy (SEM) and X‐ray diffraction (XRD). The results show that the main crystal phases are corundum and mullite, and the most suitable sintering temperature is 1250°C. At the sintering temperature apparent density is 2.84 g/cm3, and breakage ratio is 7.16% under 52 MPa closed pressure. Magnesium slag will react with some oxides of raw material at high temperature and form liquid phase, making the structure of ceramic more compact. The prepared ceramic proppants meet China industrial standard requirements SY/T5108‐2014.