The Quellaveco copper-molybdenum concentrator, commissioned in June 2022, processes open-pit ore through a conventional crushing, milling, and flotation circuit at 3,500 masl, with recent throughput reaching 142 kt/d.
Report context
This report is dated 3 November 2025 (FINAL) and describes the Quellaveco processing facilities as of that date. The concentrator was commissioned in June 2022 with a nominal capacity of 127.5 kt/d, subsequently increased to 133.3 kt/d based on plant performance, and is achieving 142 kt/d throughput, which forms the basis of the Life of Asset Plan (LoAP). Anglo American is considering options to achieve 150 kt/d. The plant is located at an elevation of 3,500 masl, presenting design challenges related to extreme cold weather and oxygen deprivation.
Processing route
Comminution and grinding
Run-of-mine (ROM) ore is delivered by truck to twin primary gyratory crushers. Crushed ore is conveyed via a 4.7 km overland conveyor with a tunnel to a coarse ore stockpile with 75 kt live capacity. The primary crusher plant is designed for up to 10,625 t/h at 65% availability. Primary crushed ore at approximately 150 mm feeds two parallel milling circuits, each comprising one 12.4 m diameter by 6.7 m long SAG mill (23.5 MW drive) and one 8.5 m diameter by 13.4 m long ball mill (22.2 MW drive) in closed circuit with cyclones. The final grind target is P80 150–180 µm.
Flotation and regrind
Milled product is conditioned with flotation reagents and pumped to flotation. The flotation circuit consists of four banks of rougher tank cells, each bank with eight 300 m³ cells. Rougher concentrate is reground in three regrind vertimills, with the fine product reporting to a twin stream cleaner/cleaner scavenger circuit, followed by final cleaning in four column flotation cells. A coarse particle flotation (CPF) circuit with Hydrofloat technology treats rougher flotation tailings to improve overall recovery.
Molybdenum separation and concentrate handling
Bulk concentrate containing copper, molybdenum, and silver is thickened in one 50 m diameter thickener and pumped to the molybdenum separation circuit. Molybdenite is recovered via selective reverse flotation using twin stream multi-stage flotation. Float tails report to the final copper concentrate thickener, while multi-stage cleaner concentrate reports to the molybdenum concentrate filtration plant. Final copper concentrate is filtered to a low moisture filter cake and trucked to the export terminal at Ilo. Molybdenum concentrate is filtered, dried, and trucked to refineries in Chile or for export.
Tailings and ancillary facilities
Tailings are thickened in twin 120 m diameter thickeners to approximately 50% solids and pumped via an 18 km launder to the Cortadera TSF, with reclaim water returned to the plant. Ancillary facilities include reagent storage and mixing, a blower, and compressed air. Milk of lime is delivered as hydrated lime with a target pH of 11.0–11.5 for copper recovery optimization. Solid (xanthate) and liquid flotation reagents (collectors and frothers) are stored and mixed on site. Flocculant is used in thickening. Sulphuric acid is used for molybdenum flotation at pH 8. Reagent storage capacity is about 15 days onsite and 7 days for lime. Grinding balls (125 mm diameter for SAG, 75 mm for ball milling) have expected consumption of 0.25 kg/t and 0.50 kg/t respectively, with 7 days storage in plant bins. Blower air is supplied to flotation tank cells, and compressed air is available for instrumentation and general use.
Recent performance
The plant ramp-up in tonnage was achieved at the end of 2023, with 4.0 Mt milled per month. Head grade has decreased from about 1.0% Cu to a current grade of about 0.8% Cu. Molybdenum grade is less than 0.03%, averaging 0.018%, with 2025 head grade at 0.015% Mo. Silver head grade ranges from 1.9 g/t to 3.3 g/t Ag, averaging 2.3 g/t Ag. Copper concentrate production is about 100 kt/m (dry) with concentrate grade ranging from 33% to 27% Cu. In the first six months of 2025, copper recovery ranged from 80% to 85% (average 82%), and molybdenum recovery averaged 65%. Monthly mill runtime varies from 88% to 99%, with an average of 94%. At full production, the concentrator requires approximately 170 MW of power, 35 ML/d of water (with 85% recycle), and about 100,000 t/a of process consumables.
Key reported parameters
| Parameter | Value | Basis |
|---|---|---|
| Nominal capacity (original) | 127.5 kt/d | Design |
| Nominal capacity (increased) | 133.3 kt/d | Plant performance |
| Current throughput | 142 kt/d | Actual |
| Potential expansion | 150 kt/d | Under consideration by Anglo American |
| Equivalent annual throughput | 38–40 Mt/a at 5,600 t/h and 0.98% Cu | Design |
| Plant elevation | 3,500 masl | Site condition |
| Primary crusher capacity | 10,625 t/h at 65% availability | Design |
| Coarse ore stockpile live capacity | 75 kt | Design |
| Overland conveyor length | 4.7 km | Design |
| SAG mill dimensions | 12.4 m dia x 6.7 m long, 23.5 MW | Design |
| Ball mill dimensions | 8.5 m dia x 13.4 m long, 22.2 MW | Design |
| Final grind size | P80 150–180 µm | Design |
| Rougher flotation | 4 banks x 8 x 300 m³ cells | Design |
| Regrind mills | 3 vertimills | Design |
| Column flotation cells | 4 | Design |
| Bulk concentrate thickener diameter | 50 m | Design |
| Tailings thickener diameter | 2 x 120 m | Design |
| Tailings launder length | 18 km | Design |
| Tailings solids density | ~50% | Design |
| Lime pH target | 11.0–11.5 | Process requirement |
| Molybdenum flotation pH | 8 | Process requirement |
| Reagent storage | ~15 days | Site inventory |
| Lime storage | 7 days | Site inventory |
| Grinding ball consumption, SAG | 0.25 kg/t (125 mm) | Expected |
| Grinding ball consumption, ball mill | 0.50 kg/t (75 mm) | Expected |
| Grinding ball storage | 7 days | Site inventory |
| Monthly mill runtime | 88–99%, average 94% | Actual (reported) |
| Copper head grade, current | ~0.8% | Actual |
| Copper recovery (H1 2025) | 80–85%, average 82% | Actual |
| Molybdenum recovery | Average 65% | Actual |
| Molybdenum head grade | <0.03%, average 0.018%; 2025 at 0.015% | Actual |
| Silver head grade | 1.9–3.3 g/t, average 2.3 g/t | Actual |
| Copper concentrate production | ~100 kt/m (dry) | Actual |
| Copper concentrate grade | 33–27% Cu | Actual range |
| Power demand at full production | ~170 MW | Reported requirement |
| Water demand at full production | 35 ML/d (85% recycle) | Reported requirement |
| Process consumables | ~100,000 t/a | Reported requirement |
Project website: https://www.angloamerican.com/our-portfolio/our-products/copper/quellaveco
Technical qualifications
The report presents design specifications, actual operating data, and testwork observations. The 142 kt/d throughput is an actual operating level used as the basis for the LoAP, while the 150 kt/d expansion remains under consideration by Anglo American and is not yet committed. Production data reported in figures and tables are sourced from Quellaveco production records; the report states that the Qualified Person is of the opinion that the selected milling and flotation process is suitable for Quellaveco ore and that concentrator performance is fair and reasonable. The report notes the plant was commissioned in June 2022, with ramp-up achieved at the end of 2023, and does not provide long-term historical performance data beyond monthly figures shown in the source figures.
Source: Quellaveco , 2025 Technical Report, Section 17: Recovery Methods, FINAL 3 November 2025.
