Fester, VG, Kabwe, AM & Slatter, PT 2011, 'Diaphragm valve head loss coefficients for coarse particles transported in a non-Newtonian carrier fluid', in R Jewell & AB Fourie (eds), Paste 2011: Proceedings of the 14th International Seminar on Paste and Thickened Tailings, Australian Centre for Geomechanics, Perth, pp. 417-426, https://doi.org/10.36487/ACG_rep/1104_36_Fester (https://papers.acg.uwa.edu.au/p/1104_36_Fester/) Abstract: The head loss coefficients for coarse particles in water have been tested in turbulent flow in various types of fittings and valves (Turian et al., 1983) and it was found that they are the same as that for water only. This has not been done for coarse particles in a non-Newtonian carrier fluid to date, particularly in laminar flow. Efficient design is only possible if reliable loss coefficient data are available. For paste slurries which are in use in many industrial settings, this situation is exacerbated by the necessity to use less water, resulting in laminar flow designs becoming more common. In many applications, these pastes could contain coarse particles. The use of diaphragm valves is common in the mineral processing industries. The objective of this work is to evaluate the head loss coefficients for coarse particles transported in a non-Newtonian carrier in a diaphragm valve in laminar, transitional and turbulent flow. A silica sand-kaolin slurry was tested at various concentrations in a diaphragm valve. This work provides important information on the behaviour of coarse particles in a non-Newtonian carrier fluid when flowing through a diaphragm valve.