粉磨煅烧次序对煤系偏高岭土胶凝性能的影响  

Effect of Grinding and Calcination Sequence on Cementitious Properties of Coal-Based Metakaolin

作　　者：张凯丰 杨雨玄 刘文欢[1] 李辉[1,2,3] Zhang Kaifeng;Yang Yuxuan;Liu Wenhuan;Li Hui(School of Materials Science and Engineering,Xi’an University of Architecture and Technology,Xi’an,Shaanxi 710055;Ecological Cement Engineering Research Center of the Ministry of Education,Xi’an,Shaanxi 710055;Shaanxi Ecological Cement Concrete Engineering Research Center,Xi’an,Shaanxi 710055)

机构地区：[1]西安建筑科技大学材料科学与工程学院,陕西西安710055 [2]生态水泥教育部工程研究中心,陕西西安710055 [3]陕西省生态水泥混凝土工程研究中心,陕西西安710055

出　　处：《非金属矿》2023年第3期95-98,102,共5页Non-Metallic Mines

基　　金：国家重点研发计划项目(2021YFB3802000);国家重点研发计划项目子课题(2021YFB3802003)。

摘　　要：利用微波可对物料内外整体加热的特性,将破碎后煤系高岭岩先经微波煅烧后再磨细处理(先烧后磨),制备煤系偏高岭土。以煤系偏高岭土的活性Si、Al溶出率和微观结构形貌,以及煤系偏高岭土制备的胶砂试样的活性指数、力学和工作性能为评价指标,研究粉磨与煅烧次序对煤系偏高岭土胶凝性能影响。结果表明,当微波煅烧温度为650℃,煅烧时间为15 min时,采用“先磨后烧”和“先烧后磨”工艺制备的煤系偏高岭土,活性Si、Al溶出率分别为51.22%、80.90%和53.2%、80.75%,活性指数分别为92%和98%,28 d抗压强度分别为50.4 MPa和53.6 MPa,28 d抗折强度分别为7.6 MPa和7.8 MPa,胶砂流动度分别为158 mm和186 mm。“先烧后磨”制备的煤系偏高岭土颗粒粒径分布更细,结构更致密。In this paper,coal-based metakaolin was prepared by using the characteristics of microwave to heat the entire material inside and outside.The crushed coal-based kaolin was first calcined by microwave and then finely ground("calcining before grinding").The effects of grinding and calcination sequence on the cementitious properties of coal-based metakaolin were studied by using the active Si/Al dissolution rate and microstructure morphology of the metakaolin,and the activity index,mechanics and workability of the samples prepared with coal-based metakaolin as evaluation indicators.The results showed that when the microwave calcination temperature was 650℃and the calcination time was 15 min,the active Si and Al dissolution rates of coal-based metakaolin prepared by the"grinding before calcining"and"calcining before grinding"processes were 51.22%,80.90%and 53.2%,80.75%,respectively.The activity indexes were 92%and 98%,respectively.The compressive strengths at 28 d were 50.4 MPa and 53.6 MPa,and the flexural strengths at 28 d were 7.6 MPa and 7.8 MPa,respectively.The fluidities of the mortar were 158 mm and 186 mm,respectively.The coal-based metakaolin prepared by"calcining before grinding"had a finer particle size distribution and a denser structure.

关 键 词：微波煅烧 煤系高岭岩 辅助性胶凝材料 

分 类 号：P619.232[天文地球—矿床学] TU528[天文地球—地质学]