Efficiency of wet-grinding on the mechano-chemical activation of granulated blast furnace slag (GBFS)

Abstract

This work aims at evaluating the effect of wet grinding on the properties of blast furnace slag (BFS) and the properties of BFS-cement mixtures. Different grinding time are considered from 10 min to 50 min at intervals of 10 min. The morphology and structure properties of ground BFS and the physical properties of BFS slurries as the function of grinding duration are analyzed. BFS cement pastes with wet-grinding BFS content of 50% are characterized. Setting time, mechanical property, microstructure and hydration products analyses are performed to evaluate the performance of wet-grinding BFS. The results indicate that wet grinding is an effective method to treat BFS, which can decrease the average particle size to 2.95 μm after 50 min of grinding, but no significant influence on the bulk minimum particle size. Wet grinding not only gives rise to a transition of zeta potential value from minus to plus, but also cause the value to increase constantly with the treatment duration. Mixtures containing wet grinding BFS present high reactivity according to the shortening of setting time, improvement of mechanical strength and reduction of porosity and Ca(OH)2.