Mechanism of Mechanical Activation of Circulating Fluidized Bed Fly Ash

Circulating fluidized bed (CFB) fly ash with high loss on ignition is hard to utilize, which become a hindrance for promoting the CFB power plant. In the paper, cementitious activity of the fly ash is improved by milling it. And the effects of mechano-chemistry and carbon structure on its activity during grinding process were studied by XRD, SEM and FTIR techniques in combination with mechanical property test. The results reveal the mechanism of mechanical activation of fly ash, which is that the change of structure of carbon in fly ash is mainly contributed to improvement of its activity. In the process of grinding fly ash, carbon particles porous structure was destroyed, the water absorption of fly ash was declined, thus reducing water requirement of cementitious system and enhancing the mechanical properties of paste.