HUANG Yang, FENG Qi-ming, Gao De-zheng, WANG Wei-qing, XIE Peng, YAN Fang-fang

(School of Environmental Engineering and Resources, Southwest University of Science and Technology, Mianyang 621010, China)

Abstract: Kaolinite-pyrite cinder was separated iron ore concentrate with Fe grade of 57.5% and tailings mainly containing metakoalin using magnetic separation after magnetizing roasting. Effect of kaolinite-pyrite cinder on hydration and hardening of portland cement were characterized by calorimetry, differential thermal analysis and scanning electron microscopy. The results show that the tailings can significantly reduce the heat of hydration of cement and react with Ca(OH)2, improving the microscopic structure of the cement paste for microstructure more homogeneous dense in the late of hydration cement paste. The water requirement of normal consistency and setting time increased when containing tailings in the cement paste. When the tailings take 15% in cement, strength values of cement mortar is higher than the comparative sample and can endure 28 more days of hydration.

Key words: kaolinite; pyrite; cinder; resource; hydration; heat hydration

E-mail: huangyang1122@126.com

ACTA MINERALOGICA SINICA Vol. 33, No. 2, 2013, Page 153-157