Sustainable Mining and Metallurgy

Mixing shear significantly enhances the homogeneity of full tailings, cement and admixtures, and also affects the physicochemical properties of prepared paste slurries. However, the underlying mechanisms remain poorly understood. In order to deeply understand the effect of mixing shear on the properties of paste slurry, the meso-structure of paste slurry was tested by the Focused Feam Reflectometry (FBRM) technique to analyze the effect of shear rate on the meso-structure of full tailings paste. The results indicate that the mixing shear has a significant effect on the pastemeso-structure. As the shear rate increases,the aggregated particles in the paste are dispersed, the average chord length decreases, and the number of real-time particles increases; However, beyond a certain threshold the average chord length of the particles in the paste increases, and the measured number of real-time particles decreases, which suggests that the high-speed shear may alter the physicochemical characteristics of particle surfaces, thereby enhancing inter-particle interaction forces, and these changes further influence the rheological behavior and post-curing mechanical properties of the paste.