Romo, D & Martinson, R 2013, 'New projects – conventional or high density tailings?', in R Jewell, AB Fourie, J Caldwell & J Pimenta (eds), Proceedings of the 16th International Seminar on Paste and Thickened Tailings
, Australian Centre for Geomechanics, Perth, pp. 327-340.
The development of the Chilean copper mining industry has been accelerated as a result of the continued global demand for resources. Every mining project faces unique engineering challenges and is forced to make key decisions. In Chile new mining projects face two special challenges: to optimise fresh water consumption and energy consumption, both of which have a very high cost. Due to the scarcity of water, many new Chilean mines now make use of sea water, which is pumped from the coast to the elevated mine sites, incurring significant energy costs.
In order to optimise fresh water consumption, high density tailings disposal is an attractive option to reduce the plant make-up water requirements, in the same way as other non-conventional tailings systems. In spite of the attractiveness of this technology, it may necessitate greater installed power for the viscous tailings pump and pipeline system, depending on the specific properties of the slurry to be handled.
A new Pucobre S.A. project has faced both challenges by carrying out several engineering studies and bench scale test programs. The project is located in the IV Region in Chile, over 300 km north of Santiago, and intends to process copper sulphides at a rate over 15,000 tonnes per day, which will require a tailings deposit with storage capacity over 100 million tonnes. At this time the project has completed prefeasibility engineering.
This paper presents the initial engineering evaluations and studies undertaken to determine the most suitable location of the tailings deposition site and tailings technology by assessing water savings and energy consumption benefits of using high density tailings. The paper discusses the bench scale sedimentation, rheology and flume tests conducted and their importance in the early engineering phases needed for the trade-off studies between conventional and thickened tailings systems. The paper also presents the factors and reasons for selecting high density tailings technology as the most appropriate conceptual solution for the project.