Performance characterisation of AG/SAG mill pulp lifters using CFD techniques


The pulp lifter is an integral component of autogenous (AG) and semi-autogenous (SAG) grinding mills as it controls the throughput, performance and efficiency of mills. The slurry transport from the AG/SAG mill through grate holes into the discharge trunnion is the main function of the pulp lifter. This process develops complex flow behaviour in the region of the grate and pulp lifter. Efficient and effective removal of pulp/slurry from the mill is the key objective of the pulp lifter design.

This work aims to understand slurry flow behaviour in pulp lifter sections and its contribution to mill performance using computational fluid dynamics (CFD) modelling and Laser Doppler Anemometry (LDA) measurements applied to a laboratory scale mill. The CFD model is validated against the LDA measurements, and then used to build a cohesive computational framework for modelling industrial pulp lifters, to investigate unique problems associated with their design and performance.


• CFD reasonably predicted the LDA measured charge flow velocity and shape.

• CFD predicted the bulk flow measurements reasonably.

• The modelling technique capture the complex flow structure though pulp-lifters.

• Demonstrated the potential of this approach to model complex flows in pulp-lifters.