This 2012 technical report covers mineral processing and metallurgical testing for the Taparko-Bouroum gold assets in Burkina Faso.
Report context
The Taparko-Bouroum Assets Technical Report, dated July 2012, was prepared for High River Gold Mines Ltd under NI 43-101 standards for the Taparko and Bouroum project areas in Burkina Faso. The report documents mineral processing and recovery methods at the Taparko-Bouroum Group Property, including historical plant operations, proposed design parameters, and metallurgical testwork results.
Processing route
Ore characteristics
The Taparko-Bouroum Group Property ore is described in Section 13.1.1 as free milling in nature. Gold occurs as fine, free grains within quartz veins and as disseminations within the host rocks. The ore is amenable to gravity concentration followed by cyanidation.
Process plant description
Section 17.2 describes the process plant as a conventional carbon-in-leach (CIL) gold recovery facility. The plant flowsheet includes coarse ore stockpiling, crushing, grinding, gravity gold recovery, cyanide leaching, desorption and electrowinning, and carbon regeneration.
Coarse ore stockpiling
According to Section 17.3, run-of-mine ore is delivered to a coarse ore stockpile prior to crushing. The stockpile provides surge capacity between mining and processing operations.
Crushing
Section 17.4 details two separate crushing circuits. Hard ore crushing (Section 17.4.1) uses a primary jaw crusher followed by secondary and tertiary cone crushers in a closed-circuit arrangement. Soft ore crushing (Section 17.4.2) employs a separate circuit with a hammer mill or impact crusher to handle weathered, clay-rich material that would cause blinding in cone crushers.
Grinding
Section 17.5 describes the grinding circuit, which consists of a semi-autogenous grinding (SAG) mill followed by a ball mill in closed circuit with hydrocyclones. The SAG mill accepts crushed ore feed, and the ball mill reduces the material to the target grind size for CIL feed.
Gravity gold recovery
Section 17.6 indicates that a gravity gold recovery circuit is installed between grinding and leaching. The gravity circuit recovers coarse free gold using centrifugal concentrators, with the concentrate directed to a shaker table for final upgrading.
Cyanide leaching
Section 17.7 states that the cyclone overflow product reports to a CIL circuit. The CIL circuit consists of a series of agitated tanks where cyanide is added to dissolve gold, and activated carbon is introduced to adsorb the gold-cyanide complex. Leach residence time and carbon concentration are controlled to optimise recovery.
Desorption and electrowinning
Section 17.8 describes the stripping process where loaded carbon is treated with a hot caustic-cyanide solution to desorb gold. The pregnant solution is then processed through electrowinning cells to deposit gold onto steel wool cathodes.
Carbon regeneration
Section 17.9 notes that stripped carbon is thermally regenerated in a rotary kiln to restore activity before being returned to the CIL circuit.
Process control and monitoring
Section 17.10 indicates that the plant is equipped with a distributed control system (DCS) for process monitoring and control. Instrumentation includes flowmeters, density gauges, pH probes, and level sensors for key process areas.
Plant sampling
Section 17.11 outlines a routine sampling programme covering mill feed, mill discharge, cyclone overflow and underflow, leach feed, leach tails, carbon solutions, and final bullion.
Key reported parameters
| Parameter | Units | Design | Historical Actual | Testwork Basis |
|---|---|---|---|---|
| Process plant type | , | Carbon-in-leach (CIL) | CIL | , |
| Crushing circuit | , | Primary jaw, secondary/tertiary cone (hard ore); hammer mill (soft ore) | As designed | , |
| Grinding circuit | , | SAG mill + ball mill + hydrocyclones | As designed | , |
| Gravity recovery circuit | , | Centrifugal concentrators + shaker table | As designed | , |
| Leach circuit | , | Agitated CIL tanks | As designed | , |
| Gold desorption | , | Hot caustic-cyanide stripping | As designed | , |
| Electrowinning | , | Steel wool cathodes | As designed | , |
| Carbon regeneration | , | Rotary kiln | As designed | , |
| Ore type | , | Free milling, fine free gold in quartz veins | , | Free milling confirmed |
| Plant sampling frequency | , | Routine (mill feed, discharge, cyclone products, leach streams, carbon solutions, bullion) | As per protocol | , |
Project website: https://ca.investing.com/equities/high-river-gold-mines-ltd-company-profile
Technical qualifications
The report in Section 1.10 states that mineral processing is based on a conventional CIL flowsheet with gravity recovery. Section 17.12 provides production data from historical operations. Section 13.1.1 describes ore characteristics and metallurgical testing confirming the ore as free milling. Sections 17.14 through 17.17 report consumables, process operating costs, process capital costs, and water supply information. No additional flowsheet details, performance data, or economic analyses beyond those explicitly stated in the original sections are provided.
Source: High River Gold Mines Ltd, The Taparko-Bouroum Assets, Burkina Faso, NI 43-101 Technical Report, July 2012, Sections 1.10, 13.1.1, 17.1–17.17.
