PASTE & TAILINGS
friction, and high resistance to abrasion and impact. Its chemical resistance( up to 85 ° C), non-scaling surfaces, and ability to perform in corrosive or unstable ground conditions make it well-suited for today’ s mining operations.
In a South Australian iron ore mine, pipeline lifespan increased from 4 – 6 weeks with HDPE to 12 – 16 months with Arterra™ UHMWPE.
A comparative study modelled a 10 km pipeline transporting copper-gold tailings, analysing both HDPE and Arterra™ UHMWPE pipelines under identical conditions – flow rate, slurry density, and internal diameter.
The results showed a total head loss of 204.2 m for HDPE, compared to 174.5 m for Arterra™ UHMWPE pipelines. This translated to a 14.5 % reduction in power consumption, saving 2.1 GWh annually, along with a 1,418-tonne reduction in carbon emissions and A $ 302,346 in energy costs per year.
These findings were supported by Computational Fluid Dynamics( CFD) simulations, which confirmed the significance of weld beads in increasing flow turbulence and head requirements. Furthermore, unlike HDPE, which is limited by standardised sizing, Arterra™ UHMWPE pipelines are manufactured with customised internal diameters.
Weir has introduced Arterra™ Ultra High Molecular Weight Polyethylene( UHMWPE) pipelines
ATMOS on tailings pipeline leak detection
Pipeline leak detection specialist ATMOS International told IM that high profile tailings failures, evolving regulation and growing community awareness have pushed operators to reexamine not just how tailings are stored, but how they are transported. In regions such as Peru and Chile, where mining frequently operates in high consequence environments, tailings pipelines are increasingly recognised as
critical risk assets rather than simple transfer lines.
“ This shift has important implications for leak detection. Technologies that work well for clean liquids or stable process pipelines do not always translate effectively to tailings service. To manage risk properly, operators need to understand why tailings pipelines are fundamentally different and why leak detection strategies and technologies must reflect that reality.”
It adds that unlike long distance oil or gas pipelines, tailings lines are rarely static assets. They often include flexible hoses that must be moved or replaced as tailings storage facilities expand. Discharge points change, sections are taken in and out of service and in some cases, relatively short pipelines include multiple outlets that are used intermittently depending on operational needs.
“ This constant evolution complicates instrumentation. Sensors installed today may need to be relocated tomorrow. Harsh slurry conditions shorten instrument life too. Access can be limited, particularly in remote or elevated terrain. Any leak detection system that relies on dense instrumentation along the pipeline must contend with high installation cost, ongoing maintenance burden and operational disruption. At the same time, the consequences of failure are severe. A leak in a tailings pipeline can release large volumes of contaminated slurry into soil and waterways, potentially triggering landslides, damaging ecosystems and impacting downstream communities.
Sika admixtures help address problems of muscovite in cemented paste backfill
A recent study presented at Paste 2025 in Swakopmund, Namibia by Ikram Elkhoumsi and Tikou Belem from the Université du Québec en Abitibi-Témiscamingue, Canada; Mostafa Benzaazoua from Mohammed VI Polytechnique University, Morocco; and Sika Canada Inc’ s Sara Arcila-Gut explores the substantial impact of muscovite content on both the rheological and mechanical properties of Cemented Paste Backfill( CPB). High muscovite percentages, particularly at 18 %, significantly increase yield stress and viscosity-up to four times higher than CPB without muscovite – indicating a pronounced negative effect on workability. The addition of an admixture( A1) mitigates these adverse effects by reducing water demand, yield stress, shear stress and viscosity, for all muscovite contents investigated in this study. The admixture was provided by Sika and selected based on its compatibility with both muscovite and GUL-binder( primitive cementitious paste). At low to moderate muscovite contents( 0-8 % M80), A1 eliminates water demand entirely at optimal dosages( 0.75-1.5 % wt % A1) and reduces yield stress by up to 97.1 %, significantly easing flow initiation and pumpability. Even at high muscovite content( 18 % M80), A1 achieves a 55.6 % water demand reduction and a 58.5 % yield stress decrease. Shear stress reductions are most pronounced at low shear rates(~ 57 %), where particle agglomeration dominates, while high shear rates see smaller reductions(~ 16 %) as inertial forces prevail. These improvements demonstrated the A1 admixture effectiveness in modifying particle interactions, improving particle dispersion and reducing internal friction, thereby enhancing flowability and pumpability. In addition to its rheological benefits, A1 contributed to substantial strength gains at both 7-days and 28-days curing stages, proving its dual role in improving workability and mechanical performance. At 68 % solids content, UCS growth ranges from 22 to 51 % at 7 days and 48 to 136 % at 28 days with 3 % A1. For 72 % solids content, gains are slightly lower but still substantial, ranging from 26.1 to 94.8 % at 7 days and 2 to 64 % at 28 days. Notably, the highest gains occur in lower-solids formulations( 68 % Cw), where A1 maximises strength development even at elevated muscovite levels, reaching up to 136 % UCS improvement after 28 days. The study highlights also the effectiveness of admixtures in optimising mix designs, as they not only compensate for UCS loss in both 68 and 72 % solid mixes but also enhance strength recovery, with 3 % A1 dosage enabling 68 % solid mixes to approach or even exceed the UCS of the 72 % solid reference while mitigating the adverse effects of the various muscovite additions. For the full paper see Ikram Elkhoumsi, I; Belem, T & Arcila-Gut, S 2025,‘ Assessment of the flowability and compressive strength of cemented paste backfills composed of muscovite-rich tailings: impact of admixtures,’ in AB Fourie, A Copeland, V Daigle & C MacRobert( eds), Paste 2025: Proceedings of the 26th International Conference on Paste, Thickened and Filtered Tailings, Australian Centre for Geomechanics, Perth, pp. 481-496, https:// doi. org / 10.36487 / ACG _ repo / 2555 _ 34
60 International Mining | MARCH 2026