Loan, C & Arbuthnot, IM 2010, 'Transforming paste thickener technology', in R Jewell & AB Fourie (eds), Paste 2010: Proceedings of the Thirteenth International Seminar on Paste and Thickened Tailings, Australian Centre for Geomechanics, Perth, pp. 365-373, https://doi.org/10.36487/ACG_rep/1063_31_Loan (https://papers.acg.uwa.edu.au/p/1063_31_Loan/) Abstract: Paste thickeners emerged as a technology in the mid 1990s, delivering previously unachievable underflow densities and associated handling properties. Paste underflows were achieved through self-compressive forces within the deep bed of the thickener. High sidewall paste thickeners, however, resulted in significant design difficulties and cost penalties. After two years of internal research, Outotec has determined that applying uniform cumulative shear to settling flocculated aggregates results in a substantial change to the sedimentation process. Applying this uniform cumulative shear to the correct settling zone increases both the throughput of a thickener and its resultant underflow density, reducing the reliance on compressive forces. Such a change in the sedimentation process results in considerable design implications for full-scale paste thickeners. These would include a major reduction in the required unit area and removing the need for high sidewall thickeners. The theory and development of ‘shear enhanced thickening’ (SET), combined with laboratory, pilot scale verification and full-scale technology implementation, will be discussed.