煤矸石的表面活化对其微观结构和性能的影响

Effects of surface activation on the microstructure and performance of coal gangue

采用流态化煅烧对煤矸石粉料进行表面活化处理,研究煅烧温度和保温时间对煤矸石中高岭石脱水反应程度、煤矸石比表面积和微观结构的影响,测定掺30%煅烧煤矸石水泥的标准稠度用水量和凝结时间。结果表明:650、700、750和800℃下分别流态化煅烧1、2. 5和5 min时,煤矸石中高岭石分解率为3%～49. 8%,高岭石未完全转化成偏高岭石; 30%表面活化煤矸石使水泥标准稠度用水量提高2. 5%～5. 5%,而30%完全活化煤矸石使水泥标准稠度用水量提高9. 1%～16. 4%。

The surface activation of coal gangue powder was carried out by fluidized calcination and the effects of calcination temperature and holding time on the mineral composition,the specific surface area and microstructure of surface-activated coal gangue were investigated. The water requirement of normal consistency and setting time of cements incorporated with 30% surface-activated coal gangue were measured. Results showed that kaolinite was completely converted into metakaolinite,and the decomposition of kaolinite was 3%-49. 8% when coal gangue powder was heated in suspended air at 650,700,750 and 800 ℃ for 1,2. 5 and 5 min. Compared with pure cement paste,the water requirement of normal consistencyof cement with 30% surface-activated and fully activated coal gangues was increased from 2. 5% to 5. 5% and 9. 1% to 16. 4%,respectively.