Authors: Slatter, PT


DOI https://doi.org/10.36487/ACG_repo/563_10

Cite As:
Slatter, PT 2005, 'Tailings Transport – Back to Basics!', in R Jewell & S Barrera (eds), Proceedings of the International Seminar on Paste and Thickened Tailings, Australian Centre for Geomechanics, Perth, pp. 165-176, https://doi.org/10.36487/ACG_repo/563_10

Download citation as:   ris   bibtex   endnote   text   Zotero


Abstract:
The underlying principles of tailings transportation are strongly influenced by the paradigms of conventional Newtonian engineering hydrodynamics. However, fundamental differences exist, and the objective of this presentation is to high- light these, and their practical implications. The Bingham plastic rheological model is accepted as an appropriate point of departure, and the fundamentals of the development of the engineering hydrodynamics of tailings transport are presented. In particular, the meaning, measurement, importance and implications of the yield stress are explored. The exploitation of tailings rheology for pressure gradient prediction is then presented, emphasising the key role that the yield stress plays in turbulent, transitional and laminar pipe flow. Discussion centres around the prob- lems associated with the application of each flow regime, and the case for opera- tion in the transition zone is argued. 166 Paste 2005, Santiago, Chile Tailings Transport - Back to Basics! Slatter, P.T. This paper presents a cost comparison between pumping large volumes of dilute thickener feed to a remote thickener located at the tailings storage facility (TSF), and using high pressure positive displacement pumps pumping thickened tailings from a thickener located at the process plant to the tailings residue facil- ity. The study considers only the pump and pipeline system capital and operating costs, and specifically excludes all costs associated with preparation and place- ment. This study shows that for a 2.5 km distance both options have a similar net present cost. As the distance increases to 5 km it is better to locate the thickener at the process plant and pump high density thickened tailings using piston dia- phragm pumps. This is mainly due to the differences in annual operating costs over the life of mine as it is not energy efficient to pump large volumes of dilute slurry long distances. Each site assessment is obviously project specific and this trade-off study shows that it is not immediately obvious as to which pumping solution is the most cost effective.

References:
Cooke, R. (2002) Laminar flow settling: The potential for unexpected problems,
Proc. 15th Int. Conf. on Hydrotransport, Banff, Canada, 3-5 June.
Clayton, S., Grice, T.G. and Boger, D.V. (2003) Analysis of the slump test for on-
site yield stress measurement of mineral suspensions, Int. J. Miner. Process. 70,
pp. 3–21.
Graham, L.J.W., Pullum, L., Chryss, A. and Rudman, M. (2001) Transition to
Turbulence in Non–Newtonian Pipe Flow, 6th World Congress of Chemical En-
gineering, Melbourne, Australia, pp. 23-27.
Huq Md, N. and Slatter, P.T (1998) Real-time identification of the laminar/turbu-
lent transition, 6th Cape Technikon Conference in Civil Engineering, Cape
Technikon, 8th October, 1998.
Jewell, R.J., Fourie, A.B. and Lord, E.R. (Eds) (2002) Paste and Thickened Tail-
ings – A Guide. Published by the Australian Centre for Geomechanics, University
of Western Australia, UniPrint, 2002, pp. 173.
McComb, W.D. (1990) The physics of fluid turbulence, Oxford University Press,
Oxford, ISBN 0-19-856160-1.
McComb, W.D. (2005) Private Communication.
Moody, L.F. (1944) Friction factors for pipe flow, Trans ASME November, 1944.
Nguyen, Q.D. and Boger, D.V. (1992) Measuring the flow properties of yield
stress fluids, Annu. Rev. Fluid Mech. 24, pp. 47-88.
Park, J.T., Mannheimer, R.J., Grimley, T.A. and Morrow, T.B. (1989) Pipe flow
measurements of a transparent non-Newtonian slurry, Journal of fluids engineer-
ing, Vol. 111, pp. 331-336.
176 Paste 2005, Santiago, Chile
Tailings Transport - Back to Basics! Slatter, P.T.
Pullum, L., Graham, L.J.W. and Slatter, P.T. (2004) A non-Newtonian two-layer
model and its application to high density hydrotransport, British Hydromechan-
ics Research Group 16th International Conference on Hydrotransport; Santiago,
April, 2004. ISBN 1 85598 054 1, pp. 579-594.
Slatter, P.T. (1999) The role of rheology in the pipelining of mineral slurries, Min.
Pro. Ext. Met. Rev., Vol 20, pp. 281-300.
Slatter, P.T. (2002) Non-Newtonian Laminar Pipe Flow – A Place In The Sun At
Last!; Invited Keynote Address - 11th International Conference on Transport and
Sedimentation of Solid Particles - Ghent, September, 2002, ISBN 83-87866-34-2,
pp. 33-40.
Slatter, P.T. (2004) The Measurement And Role Of Rheology In Paste Pipelining;
Invited Keynote Address, Paste 2004, International Seminar on Paste and Thick-
ened Tailings, Cape Town 31 March-2 April, 2004.
Slatter, P.T. and Lazarus, J.H. (1993) Critical flow in slurry pipelines; British
Hydromechanics Research Group 12th International Conference on Slurry Han-
dling and Pipeline Transport HYDROTRANSPORT 12; Brugge, Belgium: 28-30
September, 1993, ISBN 0 85298 874, 5 pp. 639 – 654.
Slatter, P.T. and van Sittert, F.P. (1997) The effect of pipe roughness on non-
Newtonian turbulent flow; 9th International Conference on Transport and Sedi-
mentation of Solid Particles - Cracow: 2-5 September, 1997, ISBN 8385582232
pp. 621 – 635.
Slatter, P.T. and Wasp, E.J. (2000) The laminar/turbulent transition in large pipes;
10th International Conference on Transport and Sedimentation of Solid Particles
- WrocBaw: 4-7 September, 2000, ISBN 83 - 87866 - 12 - 1, pp. 389 – 399.
Wilson, K.C. (1979) Deposition Limit Nomograms for Particles of Various Den-
sities in Pipeline Flow, 6th International Conference on the Hydraulic Transport
of Solids in Pipelines, BHRA, Canterbury, UK, September 1979.
Paste 2005, Santiago, Chile 177
Session X Título sección
Determining the Optimum Location of a
High Rate Thickener for a Thickened Tailings System
A.J.C. Paterson
Paterson & Cooke Consulting Engineers Pty Ltd, South Africa
This paper presents a cost comparison between pumping large volumes of
dilute thickener feed to a remote thickener located at the tailings storage facility
(TSF), and using high pressure positive displacement pumps pumping thickened
tailings from a thickener located at the process plant to the tailings residue facil-
ity. The study considers only the pump and pipeline system capital and operating
costs, and specifically excludes all costs associated with preparation and place-
ment.
This study shows that for a 2.5 km distance both options have a similar net
present cost. As the distance increases to 5 km it is better to locate the thickener
at the process plant and pump high density thickened tailings using piston dia-
phragm pumps. This is mainly due to the differences in annual operating costs
over the life of mine as it is not energy efficient to pump large volumes of dilute
slurry long distances.
Each site assessment is obviously project specific and this trade-off study shows
that it is not immediately obvious as to which pumping solution is the most cost
effective.




© Copyright 2021, Australian Centre for Geomechanics (ACG), The University of Western Australia. All rights reserved.
Please direct any queries or error reports to repository-acg@uwa.edu.au