Ortiz, A, Rosewall, A & Goosen, P 2017, 'Pumping system design challenges for high-density iron ore tailings with highly variable slurry rheology', in A Wu & R Jewell (eds), Proceedings of the 20th International Seminar on Paste and Thickened Tailings
, University of Science and Technology Beijing, Beijing, pp. 105-114.
Fine iron ore tailings slurry is commonly deposited in tailings storage facilities across the Pilbara region of Western Australia. Many of these mines process ore from a combination of deposits such as Bedded Iron Deposits (BID), Channel Iron Deposits (CID) and Detrital Iron Deposits (DID), mixing the feed to obtain the product under contract. Each one of these ore deposits presents different particle size distribution and mineralogy, including clay composition, which translates into highly variable properties (and in particular, rheology) for the tailings slurry. This variability in the slurry can occur over a mining cycle (several weeks) or even over the course of a day.
The iron ore process plants typically aim to manage the output solids concentration through the operation of the tailings thickener/s. Thickened tailings systems, due to the relatively high slurry concentration, can experience large changes in slurry rheology with relatively small variations in solids concentration or mineralogy. This high variability in the slurry rheology may became problematic for the thickener control system, operations personnel and finally the tailings pipeline.
This paper discusses some of the challenges encountered when designing high-density tailings pumping systems where the expected rheology “envelope” is significantly wide. Additionally, comments are made on key considerations for the selection of pumping equipment and the pipeline to be able to cope with these potential rheology variations throughout the life of the project.
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