Howie, E, Orlov, I, Veevers, JM & Reyes, E 2025, 'Praestospeed 120 Modular Dissolving System: a novel technology to improve the performance of flocculants on tailings management operations', in AB Fourie, A Copeland, V Daigle & C MacRobert (eds), Paste 2025: Proceedings of the 27th International Conference on Paste, Thickened and Filtered Tailings, Australian Centre for Geomechanics, Perth, pp. 641-654, https://doi.org/10.36487/ACG_repo/2555_46 (https://papers.acg.uwa.edu.au/p/2555_46_Veevers/) Abstract: In a time where tailings management operations have gained increased focus within the mineral processing industry, the process of using flocculants to maximise the rate of solid-liquid separation is becoming more common practice across a variety of tailings management operations. This paper describes how important it is for mineral processing operations to achieve optimal flocculant preparation for both flocculated tailings treatment and filtered tailings operations. For the flocculation of mineral tailings slurries to be cost-effective it is essential to maximise the hydration properties of the flocculant while still achieving the required flocculant performance; whether it is applied directly to the tailings deposition area, into a tailings thickener feed or prior to tailings filtration. Solenis, through its development of the Praestospeed™ 120 Modular Dissolving System, is able to offer improvements to the flocculant make-up in a manner that is beyond the capabilities of conventional equipment and with a significantly reduced footprint. The use of this unit provides sustainable tailings management for large-scale tailings operations, enabling lower flocculant dose requirements together with a reduction in freshwater requirements. The main features for this development are described in this paper, together with some recent full-scale examples in tailings operations. Keywords: sustainability, flocculants, solid-liquid separation, tailings management, filtered tailings, polymertreated tailings, Praestospeed 120 Modular Dissolving System