Overview
Nestled in the mineral-rich Carajás Mineral Province of Pará State, Brazil, the Luanga PGM + Au + Ni Project represents a significant development in the global platinum group metals (PGM) and nickel mining landscape. Operated by Bravo Mining Corp., a junior mining company focused on exploration and development in South America, this ambitious project sits on a vast lateritic deposit containing palladium (Pd), platinum (Pt), rhodium (Rh), gold (Au), and nickel (Ni). The strategic location benefits from proximity to established mining infrastructure, including major power grids and transportation networks, which is crucial for its economic viability. A Preliminary Economic Assessment (PEA) effective July 7th, 2025, and prepared by independent consultants GE21 Consultoria Mineral, outlines a robust plan to develop a large-scale processing facility. The project is designed with a phased approach, starting at an initial throughput of 5 million tonnes per year (Mtpy) and ramping up to a full capacity of 10 Mtpy from the third year of operation. This development is poised to become a major supplier of critical battery metals and precious metals, contributing significantly to the local economy and the global supply chain for these essential commodities.
Key Process Stages
The Luanga project will employ a conventional and well-proven mineral processing flowsheet designed to handle fresh material, with a smaller portion of oxidized material to be stockpiled for treatment later in the mine’s life. The circuit is engineered for high efficiency and recovery of the valuable metals, incorporating crushing, grinding, classification, flotation, and dewatering stages. The design is based on extensive metallurgical test work and benchmarking against similar global operations, ensuring operational reliability and optimal performance.
- Stage 1: Primary Crushing Run-of-Mine (ROM) ore is delivered to a primary crushing yard. Material is either fed directly via a fixed grizzly or stockpiled and later reclaimed by a front-end loader into a feed hopper. An apron feeder then transports the ore to a primary MMD 1300 two-axis sizer crusher, powered by an 800 kW motor, which reduces the rock to a conveyable size.
- Stage 2: Three-Stage Comminution Circuit The crushed ore is conveyed via a Long Distance Belt Conveyor (LDBC) to a stockpile feeding the grinding circuit. This sophisticated circuit consists of three key steps: a primary Semi-Autogenous Grinding (SAG) mill (36′ x 17′, 12.8 MW), a secondary open-circuit ball mill for coarse grinding (24′ x 40′, 13.5 MW), and two parallel tertiary ball mills (24′ x 40′, 13.5 MW each) in closed circuit with hydrocyclones. The SAG mill discharge is screened, with oversize (“pebbles”) sent to two HP500 cone crushers before being recirculated. The target final grind size is a very fine P80 of 28 microns to liberate the valuable minerals.
- Stage 3: Classification and Thickening The milled slurry is classified by a battery of sixty-eight 15-inch hydrocyclones. The cyclone overflow (the fine, 28µm product) is pumped to a large 30-meter diameter high-capacity thickener. This step is critical for dewatering the dilute slurry, increasing the pulp density from around 15-20% solids to a thicker slurry, and recovering process water for recycling.
- Stage 4: Froth Flotation The thickened underflow is conditioned to achieve an optimal 35% solids density for flotation. A four-stage flotation circuit is employed: Rougher (4 cells), Scavenger (3 cells), Cleaner (3 cells), and Recleaner (1 column cell). This configuration maximizes recovery; rougher concentrate is upgraded in the cleaners, while rougher tails are scavenged for any remaining values. Scavenger concentrate is recycled to the rougher stage, and cleaner tails are also recycled, creating a highly efficient and selective process to produce a high-grade final concentrate.
- Stage 5: Concentrate and Tailings Dewatering The final recleaner concentrate is thickened and filtered using a pressure plate filter to produce a damp filter cake for transport. Crucially, the plant employs a dry stack tailings (DST) facility for environmental sustainability. Flotation tailings are thickened, and the underflow is pumped to filter presses. The resulting “filter cake” with ~12% moisture is transported by truck to a dedicated storage facility, spread in 20 cm layers, and mechanically compacted to ensure geotechnical stability, drastically reducing water consumption and environmental risk compared to conventional tailings dams.
Critical Data
The following table summarizes the key operational and design parameters for the Luanga processing plant, illustrating the scale and efficiency targets of this major project.
| Parameter | Value | Unit | Notes |
|---|---|---|---|
| Design Throughput (Years 1-2) | 5 | Mtpy | Ramp-up phase |
| Design Throughput (Year 3+) | 10 | Mtpy | Full capacity operation |
| Average Head Grade (4E) | 1.4 | g/t | Pd, Pt, Rh, Au combined |
| Grinding Circuit Power | 53.3 | MW | SAG Mill (12.8MW) + 3 Ball Mills (13.5MW each) |
| Target Grind Size (P80) | 28 | μm | Required for effective mineral liberation |
| Bond Work Index (BWi) | 13 | kWh/t | Indicates medium hardness ore |
| Annual Concentrate Production | 184 | k tonnes | Filtered concentrate for shipping |
| Concentrate Grade – Ni | 4.72 | % | High-grade nickel concentrate |
| Plant Utilization (Grinding/Flotation) | 92 | % | High availability target |
| Total Project Power Demand | 80 | MW | To be supplied via 35km, 230kV transmission line |
Additional Interesting Data and Summary
Beyond the core processing circuit, the Luanga PEA outlines several critical infrastructure and sustainability components that underscore the project’s modern design philosophy. The commitment to a Dry Stack Tailings (DST) facility is a standout feature, reflecting industry best practices for environmental, social, and governance (ESG) compliance. The DSF is designed with a massive storage capacity of 65.7 million cubic meters, occupying 122 hectares. The meticulous compaction procedure—aiming for 95% of Standard Proctor at the edges and 85% in the center—ensures exceptional geotechnical stability and minimizes the long-term environmental footprint, addressing major concerns associated with traditional tailings dams.
Water management is another pillar of the project’s sustainability framework. The plant is designed for maximum water recycling, utilizing overflows from the concentrate and tailings thickeners to supply the majority of the process water demand, significantly reducing freshwater intake. Freshwater will primarily be sourced from an on-site reservoir with a capacity of 2.7 million cubic meters, created by a 15-meter high dam. A contingency plan involving a 4.88 km pipeline to divert water from the external Sereno River (up to 136 m³/h) is in place to mitigate drought-related risks, demonstrating proactive water stewardship.
The power supply strategy involves a significant investment of US$17.3 million to connect to the regional grid via a new 35-kilometer, 230 kV transmission line from the Carajás Substation, to be built by Equatorial Energia. This connection to reliable grid power, as opposed to diesel generation, will result in a lower carbon footprint for the operation. The project’s scale is immense: at full capacity, the crushing circuit will need to handle over 1,600 tonnes per hour, while the grinding circuit will process nearly 1,400 tonnes per hour. The successful execution of the Luanga project has the potential to establish a new, multi-metal producing hub in the Carajás region, generating substantial economic benefits through job creation, local procurement, and government royalties while supplying critical metals to global markets.
Source: NI 43-101 Technical Report | Preliminary Economic Assessment | Project: Luanga PGM + Au + Ni Project | Date: July 2025
