Specific Mixing Energy: A Key Factor for Cement Slurry Quality

TLDR: In this paper, the relationships between cement mixing and cement slurry quality are investigated and a tentative explanation is proposed through a mechanism of particle deflocculation and dissolution, leading to an increase in the available specific surface area.

Abstract: In this paper, the relationships between cement mixing and cement slurry quality are investigated. Laboratory mixing conditions, using a high shear mixer, are compared to field mixing conditions, including conventional jet mixer, recirculating type mixer and batch mixer. All the mixing conditions can be reduced according to a single parameter, the specific mixing energy, that allows the comparison of laboratory and field mixing with confidence. Typical cement slurry properties, like rheology, free water, fluid loss, thickening time and compressive strength, are measured as a function of the specific mixing energy. All these properties improve when the specific mixing energy increases. The efficiency of cement additives, like dispersants and fluid-loss agents, is also found to vary significantly with the energy. A tentative explanation is proposed through a mechanism of particle deflocculation and dissolution, leading to an increase in the available specific surface area.