以煤气化渣为原料, 采用一步直接烧结法制备了全固废煤气化渣微晶玻璃, 并研究了烧结温度和时间对全固废煤气化渣微晶玻璃晶相演变、机械物理性能和微观结构的影响。结果表明, 煤气化渣具有较强的析晶能力, 得到的微晶玻璃主晶相为钙长石相。在800~1 150 ℃, 随烧结温度的升高, 微晶玻璃结晶度先增高后有所降低。过高的烧结温度会使微晶玻璃内部出现片状结构, 理化性能下降。烧结温度在1 110~1 120 ℃, 微晶玻璃晶粒细小且分布密集, 表现出较好的物理性能。烧结时间对样品性能的影响较小。在烧结温度1 120 ℃、烧结时间2 h条件下, 微晶玻璃维氏硬度为6.92 GPa, 抗折强度为38.29 MPa, 抗压强度为432.72 MPa,体积密度2.618 g/cm3, 吸水率为0.21%, 耐酸碱性分别为3.13%和0.92%, 力学性能较优, 但吸水率及化学稳定性方面还有较大提升空间。

All solid waste coal gasification slag glass-ceramics were prepared by one-step direct sintering with coal gasification coarse slag as the raw material. The effects of sintering temperature and time on crystal phase evolution, mechanical and physical properties and microstructure of all solid waste coal gasification slag glass-ceramics were studied. The results show that the coal gasification slag has strong crystallization tendency, and anorthite is the main crystal phase. As the sintering temperature increases in the range of 800~1 150 ℃, the crystallinity of glass-ceramics increases firstly and then decreases. Flake structure appears in the glass-ceramics and the physical and chemical properties decrease when the sintering temperature is too high. In the range of 1 110~1 120 ℃, the glass-ceramics are fine and densely distributed, and show good physical properties. However, the sintering time has little effect on the properties of samples. When the sintering temperature is 1 120 ℃ and sintering time is 2 h, Vickers hardness of glass-ceramics is 6.92 GPa, flexural strength is 38.29 MPa, compressive strength is 432.72 MPa, bulk density is 2.618 g/cm3, water absorption is 0.21%, and acid and alkali resistance are 3.13% and 0.92%, respectively. Excellent mechanical properties are achieved, however, there is still room for improvement in water absorption and chemical stability.