Authors: Li, AL; Been, K; Wislesky, I; Eldridge, T; Williams, D


DOI https://doi.org/10.36487/ACG_rep/1263_03_Li

Cite As:
Li, AL, Been, K, Wislesky, I, Eldridge, T & Williams, D 2012, 'Tailings initial consolidation and evaporative drying after deposition', in R Jewell, AB Fourie & A Paterson (eds), Proceedings of the 15th International Seminar on Paste and Thickened Tailings, Australian Centre for Geomechanics, Perth, pp. 25-42, https://doi.org/10.36487/ACG_rep/1263_03_Li

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Abstract:
Tailings and mine waste management has an ever-growing importance in mining, including the oil sands industry. Dewatering technologies are being adopted and further developed to reduce the environmental and social impacts of tailings management facilities as well as the risks associated with possible failure of dams that retain liquid or liquefiable tailings. The geotechnical performance of tailings deposits is one of the key issues that needs to be fully addressed for large mining projects, including oil sands projects. It has been demonstrated (Li et al., 2009) that the initial void ratio of tailings immediately following deposition is a critical parameter that affects the performance of tailings deposits under both static and seismic loading conditions, particularly the post-liquefaction stability of tailings deposits. This paper presents a design method that draws upon geotechnical modelling techniques to predict the initial void ratio of tailings following self-weight consolidation and evaporative drying achieved through thin layer deposition. The self-weight consolidation model is based on a large strain consolidation theory (Gibson et al., 1967). For evaporative drying, the governing equation is based on a desiccation model (Gilliland and Sherwood, 1933) established for moisture migration within fine-grained soils due to evaporative drying, but the method also incorporates the soil-water characteristic curve equation (Fredlund and Xing, 1994). Analytical solutions have been derived for the governing equations. The modelling tools developed and presented in this paper provide a means to estimate an optimum layer thickness and drying period to increase in situ density of tailings and reduce the liquefaction potential of tailings deposits.

References:
Ayad, R., Konrad, J.M. and Soulié, M. (1997) Desiccation of a sensitive clay: application of the model CRACK, in Canadian Geotechnical Journal, Vol. 34, pp. 943–951.
Abu-Hejleb, A.N. and Znidarcic, D. (1995) Desiccation theory for soft cohesive soils, Journal of Geotechnical Engineering, Vol. 121, No. 6, pp. 106–114.
Casteleirio, M., Krizek, R.J. and Edil, T.B. (1981) Mathematical model for one-dimensional desiccation and consolidation of sedimented soils, in International Journal for Numerical and Analytical Methods in Geomechanics, Vol. 5, pp. 195–215.
Been, K. and Sills, G.C. (1981) Self-weight consolidation of soft soils: an experimental and theoretical study, Geotechnique, Vol. 31, No. 4, pp. 519–535.
Benson, R.E., Jr., and Sill, B.L. (1991) Evaporative drying of dredged material, in Journal of Waterway, Port, Coastal, Ocean Engineering, Vol. 117, No. 3, pp. 216–234.
Craig, R.F. (1987) Soil mechanics, London, New York, E & FN Spon, 1997, 6th Edition.
Cooling, D.J. (2007) Improving the Sustainability of Residue Management Practices — Alcoa World Alumina Australia, Keynote Address, in Proceedings Tenth International Seminar on Paste and Thickened Tailings (Paste07), A.B. Fourie and R.J. Jewell (eds), 13–15 March 2007, Perth, Australia, Australian Centre for Geomechanics, Perth, pp. 3–16.
Consoli, N.C. and Sills, G.C. (2000) Soil formation from tailings: comparison of predictions and field measurements, in Geotechnique, Vol. 50, No. 1, pp. 25–33.
ERCB (2009) Energy Resources Conservation Board. Directive 074 – Tailings Performance Criteria and Requirements for Oil Sands Mining Schemes.
Fine Tailings Fundamentals Consortium (1995) Advances in oil sands tailings research, Alberta Department of Energy, Edmonton, Alberta, Canada.
Fredlund, D.G. (2006) Unsaturated soil mechanics in engineering practice, Terzaghi Lecture, in ASCE Journal of Geotechnical and Geoenvironmental Engineering, Vol. 132, No. 3 pp. 286–321.
Fredlund, D.G. and Rahardjo, H. (1993) Soil mechanics for unsaturated soils, New York, John Wiley & Sons.
Fredlund, D.G. and Xing, A. (1994) Equations for the soil water characteristic curve, in Canadian Geotechnical Journal, Vol. 31, No. 3, pp. 521–532.
Fredlund, M.D., Wilson, G.W. and Fredlund, D.G. (2002) Representation and estimation of the shrinkage curve, in Proceedings of the 3rd International Conference on Unsaturated Soils, UNSAT 2002, Recife, Brazil, pp. 145–149.
Fredlund, M.D., Stone, J., Stianson, J. and Sedgwick, A. (2011) Determination of water storage and permeability functions for oil sands tailings, in Proceedings 15 International Conference on Tailings and Mine Waste 2011, Vancouver, BC, 6–9 November, pp. 315–328.
Gibson, R.E., England, G.L. and Hussey, M.J.L. (1967) The theory of one-dimensional consolidation of saturated clays, I. Finite non-linear consolidation of thin homogeneous layers, in Geotechnique, Vol. 17, No. 2, pp. 261–273.
Gilliland, E.R. and Sherwood, T.K. (1933) The drying of solids, VI, Industrial and engineering chemistry, pp. 1134–1136.
Howell, T.A., Phene, C.J. and Meek, D.W. (1983) Evaporation from screened class A pans in a semi-arid climate, in Agriculture Meterology, Vol. 19, pp. 111–124.
Jewell, R.J. and Fourie, A.B. (eds) (2006) Paste and Thickened Tailings – A Guide, 2nd edition, Australian Centre for Geomechanics, Perth, 242 p.
Krizek, R., Casteleiro, M. and Edil, T. (1977) Desiccation and consolidation of dredged materials, in Journal of the Geotechnical Engineering Division, Vol. 103 (GT12), pp. 1399–1418.
Lee, K. and Sills, G.C. (1981) The consolidation of a soil stratum, including self-weight effects and large strains, in International Journal for Numerical and Analytical Methods in Geomechanics, Vol. 5, pp. 405–428.
Li, A.L. (2011) Prediction of tailings beach slopes and tailings flow profiles, in Proceedings 14th International Seminar on Paste and Thickened Tailings (Paste2011), R.J. Jewell and A.B. Fourie (eds), 5–7 April 2011, Perth, Australia, Australian Centre for Geomechanics, Perth, pp. 307–322.
Li, A.L., Been, K., Ritchie, D. and Welch, D. (2009) Stability of large thickened, non-segregated tailings slopes, in Proceedings 12th International Seminar on Paste and Thickened Tailings (Paste09), R.J. Jewell, A.B. Fourie, S. Barrera, J. Wiertz (eds), 21‒24 April 2009, Viña Del Mar, Chile, Gecamin Limited, Santiago, Australian Centre for Geomechanics, Perth, pp. 301–311.
Morris, P.H., Graham, J. and Williams, D.J. (1992) Cracking in drying soils, in Canadian Geotechnical Journal, Vol. 29, pp. 263–277.
Morris, P.H., Wong, L.T. and Day, R.A. (2007) Journal of Waterway, Port, Coastal, Ocean Engineering, Vol. 133, No. 4, pp. 268–274.
Richards, B.G. (1965) Determination of the Unsaturated Permeability and Diffusivity Functions from pressure plant outflow data with non-negligible membrane impedance, in Moisture Equilibria and Moisture Changes in Soils Beneath Covered Areas, G.D. Aitchison (ed), a Symposium Convened by Soil Mechanics Section, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Australia.
Stark, T.D., Choi, H. and Schroeder, P. (2005) Settlement of dredged and contaminated material placement area, I: Theory and use of primary consolidation, secondary compression, and desiccation of dredged fill, in Journal of Waterway, Port, Costal, and Ocean Engineering, Vol. 131, No. 2, pp. 43–51.
Swarbrick, G. and Fell, R. (1992) Modelling desiccating behaviour of mine tailings, in Journal of Geotechnical Engineering, Vol. 118, No. 2, pp. 540–555.
Wilson, G.W., Fredlund, D.G. and Barbour, S.L. (1994) Coupled soil-atmosphere modelling for soil evaporation, in Canadian Geotechnical Journal, Vol. 31, pp. 151–161.
Yao, D.T.C., de Oliveria-Filho, W.L., Cai, X.C. and Znidarcic, D. (2001) Numerical solution for consolidation and desiccation of soft soils, in International Journal for Numerical and Analytical Methods in Geomechanics, Vol. 26, pp. 139–161.




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