Boxill, L, Costine, A, Fawell, P, Catling, M & Bellwood, J 2018, 'Evaluating the shear resistance and ultimate dewatering performance of polymer-treated tailings', in RJ Jewell & AB Fourie (eds), Proceedings of the 21st International Seminar on Paste and Thickened Tailings
, Australian Centre for Geomechanics, Perth, pp. 277-290.
Anionic copolymers have been used to enhance the dewatering and strength development properties of a wide range of tailings substrates around the mining world for at least two decades. The evaluation and selection of polymer treatment candidates for field application is often based on results obtained from a series of screening experiments to satisfy specified key performance indicators (KPIs). However, if the screening protocol or stated KPIs fail to account for the shear environment the treated tailings will experience during polymer dosing and prior to deposition, what often results is the incorrect selection of the polymer to achieve the desired dewatering and performance criteria post-deposition.
Results from several laboratory-scale screening experiments are used to demonstrate how tailings (both analogues and industrial samples), dosed with the same polymer(s), can exhibit widely different characteristics when subjected to distinct shear conditions. This paper will also show how polymer selection would change depending on whether results from conventional screening criteria were used versus results obtained from an expanded screening protocol that accounts for some of the shear characteristics of the tailings treatment and deposition environment.
Keywords: tailings polymer treatment, topological mixing, controlled shear, conditioning time
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