Abstract: Stockpiled fly ash with high carbon-content and low reactivity was used to prepare belite cement by hydrothermal treatment followed by low temperature calcination. The effects of CaO content of starting mixture, hydrothermal treatment time at 97 ℃±2 ℃, calcination temperature and durating time on the composition of the precursor and clinker, and on the properties of the fly ash belite cement were investigated. The results show that the mullite and quartz in fly ash nearly do not take part in the reactions during hydrothermal treatment at 97 ℃±2 ℃ and calcination at 800 ℃. The main hydraulic minerals in the belite cement clinker are α’L-C2S and C12A7 when the clinker was calcined at 800 ℃, while β-C2S and gehlenite exist when the clinker was calcined at 900 ℃ or higher temperature. Fly ash belite cement with the compressive strength as high as 30.2 MPa at 28 d was prepared from mixture with the CaO content of 30%, by hydrothermal treatment at 97 ℃ for 10 h followed by calcination at 800 ℃ for 1 h. Fly ash belite cement is characterized by rapid setting, which makes it suitable for rush-repairing project, however, high water requirement which result in looser microstructure and higher porosity of the hardened cement paste.
杜 超,刘 飞,万媛媛,龚泳帆,方永浩. 低质高碳粉煤灰制备粉煤灰贝利特水泥及其特性研究[J]. 《材料导报》期刊社, 2017, 31(24): 30-34.
DU Chao, LIU Fei, WAN Yuanyuan, GONG Yongfan, FANG Yonghao. Preparation of Fly Ash Belite Cement from High-carbon Low-quality Fly Ash and Its Properties. Materials Reports, 2017, 31(24): 30-34.
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2017, Vol. 31 
