Designing the Siilinjärvi thickened tailings storage facility

Authors: Fitton, TG; Henriksson, B; Ruhanen, E Download Paper Open access courtesy of:

DOI https://doi.org/10.36487/ACG_rep/1805_19_Fitton

Cite As:
Fitton, TG, Henriksson, B & Ruhanen, E 2018, 'Designing the Siilinjärvi thickened tailings storage facility', in RJ Jewell & AB Fourie (eds), Paste 2018: Proceedings of the 21st International Seminar on Paste and Thickened Tailings, Australian Centre for Geomechanics, Perth, pp. 241-250, https://doi.org/10.36487/ACG_rep/1805_19_Fitton



Abstract:
This case study presents some of the key aspects of the design of the thickened tailings storage facility that recently commenced operation at Yara’s Siilinjärvi apatite mine in Finland. The mine is located near the Arctic Circle, and therefore operates in a cold climate. The tailings are also quite coarse (with a D90 of 700 microns), which creates challenges in the operation of a thickened tailings storage facility. This paper describes a series of pilot plant trials from 2007 to 2010 and demonstration plant beaching trials that took place in 2013 and 2014, not only in terms of the collection of data, but also with respect to the many engineering challenges that were overcome in the thickening and transport of the tailings slurry under these difficult conditions. The beaching trials provided good validating data for the design of the tailings storage facility. The beaching results are presented, along with some discussion of their comparison with the predicted beach slopes used in the tailings storage facility design. The paper further discusses and presents images of the thickeners, pumps, pipelines and tailings storage area.

Keywords: thickened tailings, beach slope, cold climate, tailings storage facility