增钙煅烧煤矸石的活性评价及其作用机理

EVALUATION OF ACTIVATION AND ITS ACTION MECHANISM OF CALCINED COAL GANGUE WITH CALCIUM

采用增钙煅烧方式活化煤矸石,添加石膏和萤石作矿化剂。对各试样进行游离氧化钙、X射线衍射和核磁共振分析,进一步探讨煅烧过程中矿物组分与微观结构的变化。结果表明:掺加的氧化钙被大量吸收。在一定温度范围内,煅烧煤矸石的硅氧四面体聚合状态发生明显变化,同时生成多种硅酸钙盐矿物。随温度升高,硅氧四面体结构从高聚态向低聚态转变,并伴随生成大量玻璃态和无定型物质,这些物质均有利于改善煤矸石的胶凝活性。

Coal gangue was activated by calcination with calcium, while gypsum and fluorite as mineralized agent. The mineral composition and microstructure of samples were detected or analyzed by free-CaO, X-ray diffraction and nuclear magnetic resonance. Results show that the mixed CaO is largely absorbed. When coal gangue is calcined at a certain temperature, obvious changes in polymerization of silicon-oxygen tetrahedron take place and multifarious silicate minerals are produced. As the temperature increases the silicon-oxygen polyhedron structures are changed from a high polymer to a low polymer state, accompanying the formation of a large amount of glass and amorphous matter, which is beneficial for improving the activation of coal gangue.