Hydraulic Dewatered Stacking – Delivering Desaturated Tailings Management Without the Capital Cost of Filtration
Phil Newman1*, Andrea López2, Mark Bruton3 and Auel Kulmagambetova1
1. Anglo American, UK
2. Anglo American, Chile
3. WSP, UK
*This paper was presented at Gecamin's 2024 Tailings Conference, held 12-14 June 2024 in Santiago, Chile. To view the full paper select download file below.
ABSTRACT
Hydraulic Dewatered Stacking (HDS) is an engineered co-disposal tailings management system, developed by Anglo American that delivers a desaturated tailings facility with benefits on safety,
water recovery and significantly changes the approach to closure generating social, environmental and cost benefits.
Conventional tailings dams have basal drainage layers but vertical permeability is poor and many tailings facilities remain saturated throughout their life and beyond mine closure. Horizontal permeability is up to 10x greater and HDS leverages dedicated drainage channels (built with sand derived from the tailings themselves) to create a 3-dimensional drainage system to continuously dewater the facility.
Results at our 150,000m3 demonstration facility have exceeded expectations although challenges remain in the scaling of the system to the target application – a large copper porphyry in a water scarce region such as Chile / Perú.
Access across the tailings has been rapid, and consolidation / moisture content measurements have shown that the zone of influence of the vertical drainage channel has been approximately 20m. Phase 2 (of 3) of the demonstration is now underway and the trial will be completed in Q3, 2024.
This paper talks to the benefits of pursuing a desaturated tailings storage solution and presents the results of a techno-economic analysis comparing filtered stacking and HDS for an indicative 3000 tph copper project in Chile.
Keywords: Hydraulic Dewatered Stacking, filtered tailings, tailings management