Sofrà, F & Boger, DV 2011, 'Rheology for thickened tailings and paste — history, state-of-the-art and future directions', 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. 131-133, https://doi.org/10.36487/ACG_rep/1104_12_Sofra
A significant development during the evolution of thickened tailings and paste technology has been the increased understanding of the importance of rheology for both design and operation of thickened tailings and paste systems. It is now well accepted that dewatering, pipeline transport and deposition processes are all rheology governed and that the more the rheology is understood, and in some cases manipulated, the more successful the operation will be. This increased knowledge and adoption of rheology has led to a paradigm shift where tailings are engineered to suit the environment rather than engineering the environment to suit the tailings.
In the early to mid 1970s when Eli Robinsky first introduced the concept of thickened tailings disposal, the systems were based primarily on empirical flume tests. Since that time, numerous advances in measurement techniques have facilitated the understanding of the influence of variables such as particle size distribution and shape, shear effects (rate and time of shear) and mineralogy on the rheology of tailings. Compressional rheology has also emerged as a whole new area of interest. This progress, coupled with advances in understanding the interrelationship between surface chemistry and rheology, has highlighted methods of exploiting and/or manipulating the dewatering, flow and depositional properties of tailings and backfill. As flocculant and other additive technologies advance, we may begin to see more complex rheological phenomena and new measurement techniques may need to be adopted or developed for a fuller understanding and exploitation of slurry and paste rheology. The paper examines the driving issues faced in the past, now and likely in the future, the testwork that has been developed and its applicability or limitations and how this has progressed thickened tailings and paste technology.
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