The slurry transport system of every mining operation is based on one of two designs: gravity feed or pump delivery. Gravitational systems are effective for mine sites located on higher ground than the tailings storage facility (TSF), particularly those that produce tailings slurries with Newtonian behavior. Under these circumstances the gravitational potential energy allows slurry transport without mechanical assistance. Pump systems are required at sites that are unable to reach the TSF with gravity alone, this can be due to the elevation change or high friction losses within the system, as is often the case with high density slurries exhibiting non-Newtonian behavior. Each operation is unique and has particular design considerations and operational parameters that must be accounted for when designing a feed system. These specificities, including concentration, tailings mineralogy and PSD, can have a major impact on the operation - as the flow behavior of the slurry may change from Newtonian to non-Newtonian or vice-versa. Slurry transport systems based on a pump can be adapted to new conditions through the versatility and flexibility afforded by the additional mechanical energy. Gravity systems on the other hand are governed exclusively by the available gravitational energy, and so accurate prediction of the behavior of non-Newtonian fluids is required. Burger et al (2014) presented a method based on experimental data to improve the design of a range of open channels to transport non-Newtonian fluids. This paper describes an alternative method to determine flow behavior for Bingham plastic fluids in open channels based on the premise used by Slatter (1994), which replaced the pipe diameter with four times the hydraulic radius for a turbulent pipe flow model.
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