Generalizing a shear–volume power model for stirred mill power prediction

• Mill geometries are decomposed into shear–volume pairs.
• The shear–volume pairs allow for a closed-form expression for the power.
• The closed-form expressions for common stirred mill geometries are given.
• The shear–volume power and the Bond equation are combined.

A stirred milling model, based on the concept of shear–volume power, was developed and applied to geometries typically found in mineral processing systems. Generalising this model permits its use to model more complex mill geometries, such as those describing a tapered disk mill and the CoBal mill. Due to the additive property of the shear–volume power, the calculation of the power of complex mills is possible through geometric decomposition. This approach is supported by the calculation of the shear–volume power of a number of simple geometries commonly found in mills, and is used in the calculation of the shear–volume power of a tapered disk mill and the CoBal mill. Finally, by incorporating a breakage model, an equation that offers some usefulness in the design, operation and optimization of stirred mills is presented.