Evaluation of rheology-modifying and conventional flocculants across various tailings through a dynamic thickening test

Authors: Matinin, A; Bower, M; Bonneau, A Download Paper Open access courtesy of:

DOI https://doi.org/10.36487/ACG_repo/2655_58

Cite As:
Matinin, A, Bower, M & Bonneau, A 2026, 'Evaluation of rheology-modifying and conventional flocculants across various tailings through a dynamic thickening test', in AB Fourie, M Horta, M Oliveira & S Wilson (eds), Paste 2026: Proceedings of the 28th International Conference on Paste, Thickened and Filtered Tailings, Australian Centre for Geomechanics, Perth, pp. 1-14, https://doi.org/10.36487/ACG_repo/2655_58



Abstract:
Modern mining operations are increasingly challenged by declining ore grades, stricter environmental regulations, and limited access to water resources. At the same time, many plants are operating above their original nameplate capacities, putting additional stress on the existing infrastructures. In the design phase of mineral processing plants, tailings thickening is often treated as a secondary process – as ‘waste’ primarily associated with tailings management. It does not always receive the same attention as the money-making parts of the process such as the flotation or leaching stages and rarely sees attention in terms of optimisation. However, poor thickening performance can have a significant negative impact on overall plant efficiency due to low water recovery and poor process water quality. Improving the flocculant chemistry is a particularly attractive approach for enhancing thickening performance. It can often be implemented rapidly without major capital expenditure (capex) or structural modifications and without impacting operational cost (opex). In many cases, conventional anionic flocculants (acrylamide-co-sodium acrylate polymer) are unable to ensure optimal performance, especially when plants are pushed above their design limits. In challenging situations with high water recovery requirements, the use of these flocculants may lead to high rake torque, poor underflow density, or unsatisfactory flux rates. Increasing the flocculant dosage is not always effective and can further exasperate the problems. Rheology-modifying flocculants, particularly those based on Sodium 2-acrylamido-2-methylpropane sulfonate (ATBS) anionic monomer, offer a competitive alternative. These flocculants are more efficient at reducing slurry viscosity. Although their overall charge density may be lower, the sulfonic acid groups in ATBS offer enhanced performance and reliability. This study compares the performance of conventional anionic flocculants with ATBS-based rheologymodifying flocculants through extensive static and dynamic testing across a variety of ore types and processing conditions. Results clearly demonstrate the potential benefits of selecting the most adapted flocculant chemistry to improve flux rates, underflow characteristics, enhance water recovery, and reduce energy consumption without a costly process redesign.

Keywords: thickening, rheology-modifying flocculants, settling rate, clarity, dynamic thickening test, yield stress, flux rate, rake torque

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