Authors: Dunmola, A; Simms, P

Purchase Paper

Cite As:
Dunmola, A & Simms, P 2010, 'Solute mass transport and atmospheric drying of high-density gold tailings', in R Jewell & AB Fourie (eds), Proceedings of the Thirteenth International Seminar on Paste and Thickened Tailings, Australian Centre for Geomechanics, Perth, pp. 279-289.

Download citation as:   ris   bibtex   endnote   text   Zotero


Abstract:
The accumulation of salts on the surface of thickened tailings is well-known to suppress evaporation and consolidation, thereby having both negative economic and environmental implications for surface deposition operations. The current research studied and related the 1D mass transport of dissolved solute within a layer of acid-generating thickened gold tailings to salt crust formation and evaporation using a model wax column technique. The electrical conductivity, matric suction, total suction and gravimetric water content at 1 cm intervals of a column of desiccating thickened tailings was determined over a period of 15 days and related to measured evaporation rates over the same period. Results from this paper showed evidence of salt accumulation at the top 1 cm of thickened tailings layer, which reduced the rate of evaporation after 12 days. Osmotic suction was observed to be the major mechanism of reduction in evaporation rate by salts, as opposed to any physical crust effects. Therefore, it may be possible to anticipate suppression of evaporation by salts through modelling ion transport, a technique that could be used to optimise thickened tailings deposition schemes with respect to controlling salt accumulation.

References:
Agus, S.S. and Schanz, T. (2005) Comparison of four methods for measuring total suction, Vadose zone J., Vol. 4(4),
pp. 1087–1095.
Akinremi, O.O. and Cho, C.M. (1991) Phosphate transport in Ca-saturated systems: II, Experimental results in a model
system, Soil Sci. Soc. Am. J., Vol. 55, pp. 1282–1287.
Bryan, R. (2008) Drying and oxidation of surface-disposed thickened tailings, M.A.Sc. Thesis, Department of Civil and
Environmental Engineering, Carleton University, Ottawa ON, Canada.
Chen, X.Y. (1992) Evaporation from salt-encrusted sediment surface: Field and laboratory studies, Aust. J. Soil
Research, Vol. 30, pp. 429–442.
Fisseha, B., Bryan, R. and Simms, P. (2009) Evaporation, unsaturated flow and oxidation in multi-layer deposits of gold
paste tailings, In Proceedings 12th International Seminar on Paste and Thickened Tailings, Australian Centre of
Geomechanics, Perth, Australia, pp. 251–260.
Fisseha, B., Glancy, T. and Simms, P. (2007) The influence of the initial degree of saturation on the shrinkage curve of
silts, In Proceedings 60th Can. Geotech. Conference, Ottawa, Canada, pp. 1010–1015.
Fredlund, D.G. and Xing, A. (1994) Equations for the soil-water characteristic curve, Can. Geotech. J., Vol. 31,
pp. 521–532.
Fujiyasu, Y. and Fahey, M. (2000) Experimental study of evaporation from saline tailings, J. Geotech. Geolo. Eng.,
Vol. 126(10), pp. 18–27.
Hao, X., Cho, L.M. and Racz, G.J. (2000) Chemical retardation of phosphate diffusion in simulated acid soil amended
with lignosulfonate, Can. J. Soil Sci., Vol. 80, pp. 289–299.
International Commission on Large Dams (ICOLD) (1989) Tailings dam safety guideline, Bulletin 74, 112 p.
Khasawneh, F.E., Sample, E.C. and Hashimoto, I. (1974) Reactions of ammonium ortho- and polyphosphate fertilizers
in soil, I. Mobility of phosphorus, Soil Sci. Soc. Am. J., Vol. 38, pp. 446–451.
Khasawneh, F.E. and Soileau, J.M. (1969) Soil preparation and sampling techniques for studying ion movement, Soil
Sci. Soc. Am. Proc., Vol. 33, pp. 476–477.
Newman, P. (2003) Thickened the answer to dam problems, Materials World, Vol. 11(1), pp. 24–26.
Newson, T. and Fahey, M. (1997) Salinization due to evaporation from tailings, Geo-environmental Engineering,
Contaminated ground: fate of pollutants and remediation, Proceeding Conference, Cardiff Thomas Telford,
London, pp. 128–133.
Olatuyi, S.O., Akinremi, O.O., Flaten, D.N. and Crow, G.H. (2009) Accompanying cations and anions affect the
diffusive transport of phosphate in a model calcareous soil system, Can. J. Soil Sci., Vol. 89(2), pp. 179–188.
Rasaam, D.W. and Williams, D.J. (1999) A relationship describing the shear strength of unsaturated soil, Can. Geotech.
J., Vol. 36, pp. 363–368.
Simms, P., Dunmola, A. and Fisseha, B. (2009) Generic predictions of drying time in surface deposited thickened
tailings in a “wet” climate, in Proceedings Mine Waste and Tailings Conf., Banff, pp. 749–758.
Simms, P., Grabinsky, M. and Zhan, G. (2007) Modeling evaporation of thickened tailings from the Bulyanhulu mine,
Can. Geotech. J., Vol. 44, pp. 1417–1432.
Williams, D.J. and Stolberg, D.J. (2006) Field performance of capillary break covers over hypersaline tailings in an arid
climate, In Proceedings 4th International Conference on Unsaturated Soils, Geotech. Special Pub. 147,
pp. 777–788.
Wilson, G.W., Fredlund, G.W. and Barbour, S.L. (1997) The effect of soil suction on evaporative fluxes from soil
surfaces, Can. Geotech. J., Vol. 34, pp. 145–157.
Solute mass transport and atmospheric drying of high-density gold tailings A. Dunmola and P. Simms
290 Paste 2010, Toronto, Canada




© Copyright 2019, 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