Analysis of Factors Affecting Pozzolanic Activity in Thermal Activated Coal Gangue

The influence factors on pozzolanic activity index(PAI) of thermal activated coal gangue,which include geographic distribution,geological age,chemical composition,mineral composition,content and crystallinity of kaolin in coal gangue,thermal activated scheme of coal gangue,have been discussed comprehensively.The results show that the pozzolanic activity of thermal activated coal gangue in the north of China is stronger than that in the south.The correlation between chemical composition of raw coal gangue and its pozzolanic activity is controlled by its geographic distribution.The PAI of thermal activated coal gangue varies with geological era.The curve of PAI variable with geological era exhibits a saddle-like distribution.The PAI of thermal activated coal gangue has a positive correlation with the content of kaolin,and a negative correlation with the crystallinity of kaolin in raw coal gangue.In the thermal activated scheme of coal gangue,there is an optimum correlation among calcined temperature,temperature-keeping time and cool style.