FPX Nickel's 2023 prefeasibility study for the Baptiste nickel project in central British Columbia makes a 60% Ni awaruite concentrate, briquetted for shipment, and a mixed hydroxide precipitate. Capacity expands to 162 kt/d from Year 10.
The Baptiste Nickel Project NI 43-101 Technical Report and Prefeasibility Study, British Columbia, Canada, was prepared by Ausenco Engineering Canada for FPX Nickel Corp., with an effective date of September 6, 2023 and a report date of October 18, 2023. The plant makes two nickel products. An awaruite (Ni3Fe) concentrate from magnetic separation and flotation accounts for about 93% of nickel production. A mixed hydroxide precipitate (MHP) recovers nickel dissolved during flotation and from leaching of the flotation tails. Phase 1 treats 108 kt/d (39.4 Mt a year), and from Year 10 an independent Phase 2 line raises the total to 162 kt/d (59.1 Mt a year). The design is based on testwork since 2012, industry benchmarks and Ausenco experience. The design head grade is 0.15% Davis tube recoverable (DTR) Ni.
Critical Data
| Parameter | Value | Unit | Notes |
|---|---|---|---|
| Report effective date | September 6, 2023 | Not applicable | Ausenco for FPX Nickel Corp. |
| Throughput | 108 kt/d Phase 1, 162 kt/d Phase 2 | Not applicable | 39.4 and 59.1 Mt/a |
| Design head grade | 0.15% DTR Ni, 2.84% DTR Fe | Not applicable | BWi 23.5 kWh/t |
| Primary crusher | 1.5 m x 2.8 m gyratory, 1,372 kW | Not applicable | 6,000 t/h, P80 85 mm |
| SAG mills | Two 11.6 m x 9.1 m EGL, 25 MW gearless | Not applicable | 2,446 t/h per line |
| Ball mills | Two 7.9 m x 13.1 m EGL, 2 x 8.4 MW | Not applicable | P80 250 µm |
| Magnetic separation | Rougher, cleaner and recleaner LIMS with scavengers | Not applicable | About 94% of DTR Ni into about 5% of the mass |
| First regrind | Horizontal ball mill to P80 65 µm | Not applicable | With a 190 t/h continuous gravity concentrator |
| Second regrind | 5,000 kW stirred mill to P80 18 µm | Not applicable | 3 to 5 mm ceramic media |
| Awaruite flotation | Four 160 m³ roughers, four cleaner stages | Not applicable | pH about 4.0 to 4.8 with SIPX |
| Awaruite concentrate | 60% Ni, 25% Fe | Not applicable | 85.4% DTR Ni recovery from flotation feed |
| Tailings leach | 8 h with sulphuric acid and air | Not applicable | About 50% Ni extraction |
| MHP | 89% of dissolved Ni recovered | Not applicable | Caustic calcined magnesia to pH 8.1 |
Overview
A single gyratory crusher feeds a covered coarse ore stockpile and two SAG-ball grinding lines. Each line feeds rougher and rougher-scavenger low-intensity magnetic separation (LIMS). The combined magnetic concentrate goes to a ball mill regrind with gravity concentration, then cleaner LIMS. A stirred mill regrind follows, then recleaner LIMS. The final magnetic concentrate is thickened and floated at mildly acidic pH to a 60% Ni awaruite concentrate. This is dewatered by LIMS and a filter press, briquetted without binder and bagged. Flotation tails are leached with sulphuric acid. A bleed of brine passes iron removal, MHP precipitation and magnesium removal.
Key Process Stages
Crushing. Run-of-mine ore at F80 312 mm is dumped into a 450 t dump pocket with a rock breaker. The gyratory crusher, choke fed where possible, runs at 75% availability. The covered stockpile holds 54 kt live (270 kt total), with two reclaim tunnels of two apron feeders each.
Grinding. Each SAG mill runs at 70% solids with 125 mm media, and its pebbles are returned to the mill. Ball mills use 60 mm media and are closed with twenty 650 mm cyclones (18 operating) at a 250% circulating load. Cyclone overflow at 35% solids goes to magnetic separation.
Magnetic separation and regrind. Rougher LIMS tails pass dedicated scavenger LIMS, and the non-magnetic tails go to the tailings facility. Tailings flow there by gravity for the first seven years, and a pumping system is added in Year 8. A single ball mill closed with cyclones regrinds the combined concentrate to P80 65 µm. A continuous centrifugal gravity concentrator on one cyclone underflow recovers liberated awaruite, about 50% of the DTR Ni in its feed. Eight cleaner LIMS with scavengers follow. The stirred mill then regrinds the cleaner concentrate to P80 18 µm ahead of recleaner LIMS.
Awaruite flotation. A 22 m high-rate thickener raises the magnetic concentrate to 70% solids. In conditioning, recycled brine and sulphuric acid dilute it to 25% solids at pH 4.0 to 4.5. Four 160 m³ rougher cells are followed by four cleaner stages of 10, 5, 3 and 3 m³ cells, held at pH 4.5 to 4.8. The cells are closed and ventilated centrally. About 2.2% of the nickel dissolves during flotation.
Concentrate dewatering and briquetting. A dewatering LIMS raises the concentrate from 20% to 65% solids. A filter press takes it to 86% solids, and the cake is washed with fresh water to displace brine. An ambient-temperature, binder-less roller press makes briquettes, which are packed in 1 m³ UN-rated bags for container shipment.
Tailings leach and MHP. Flotation tails are thickened and leached for 8 hours with sulphuric acid and air sparging, extracting about 50% of the nickel. Excess brine passes four aerated iron precipitation tanks to pH 5.5, using limestone and then lime, and an 8 m thickener. Three 233 m³ MHP tanks follow, where caustic calcined magnesia raises the pH to 8.1. The MHP is thickened in a 14 m thickener, filtered on a 52 m² press to 50% moisture and bagged. Magnesium is then precipitated with lime in two tanks.
Additional Interesting Data and Summary
The Phase 2 design conservatively treats the expansion as an independent line. Later studies will look at integrating it into the original concentrator. The sulphuric acid tank is climate controlled to prevent freezing. Limestone is ground on site in a dedicated ball mill.
In summary, the 2023 Baptiste prefeasibility study concentrates a very low-grade awaruite ore through three stages of magnetic separation and two regrinds. Acidic flotation produces a high-grade nickel-iron alloy concentrate, and a small tailings leach and MHP circuit captures the dissolved nickel.
Key Processes
- Gyratory crushing and covered stockpile
- SAG and ball milling to P80 250 µm
- Three-stage low-intensity magnetic separation
- Ball mill regrind with continuous gravity concentration
- Stirred mill regrind to P80 18 µm
- Acidic awaruite flotation with four cleaner stages
- Magnetic and filter press dewatering, briquetting and bagging
- Sulphuric acid leaching of flotation tails
- Iron removal, MHP precipitation and magnesium removal
Source: Baptiste Nickel Project NI 43-101 Technical Report and Prefeasibility Study, British Columbia, Canada, prepared by Ausenco Engineering Canada Inc. for FPX Nickel Corp., effective date September 6, 2023.
Earlier report summaries
Earlier versions of this profile, based on older technical reports, are retained below for source traceability. Dates and figures reflect each report’s own effective date and are superseded by the current information above.
Baptiste Nickel Project — 2020 PEA
This PEA outlines a 120,000 tpd mineral processing flowsheet using crushing, HPGR, ball milling, magnetic separation, and flotation to produce a 63.4% Ni concentrate from the Baptiste Deposit.
Report context
This technical report, dated September 2020, presents a preliminary economic assessment (PEA) for the Baptiste Nickel Project. The processing design is based on testwork performed using samples from the Baptiste Deposit, as described in Chapter 13 of the report.
Processing route
Primary and secondary crushing
The process flowsheet begins with primary and secondary crushing with screening, followed by stockpiling. The primary and secondary crushing plant utilization has been assumed at 70%.
HPGR and ball milling
Crushed product is fed to HPGR (high-pressure grinding roll) crushing with screening and ball milling to achieve the primary grind size. The initial primary grind size is 300 µm, dictated by the tailings deposition strategy and the tailings storage facility (TSF) design. For the first 21 years of operation (Phase 1), this grind size is the finest that will generate sufficient sand tailings to accommodate the tailings deposition plan.
Starting in Year 22 (Phase 2), process tailings will be disposed of using an in-pit deposition strategy, removing the grind size constraint. BBA performed a high-level analysis indicating that a 170 µm primary grind size should be targeted for improved DTR Ni recovery in Phase 2.
The concentrator and ancillary facilities are designed for 24 h/d, 7 d/w, 365 d/y operation. Plant utilization downstream of the crushed product stockpile has been assumed at 92%. Most equipment incorporates a design factor of 15% above nominal to account for operational variability.
Magnetic separation and regrind
Following ball milling, the ground material undergoes a primary magnetic separation step. The magnetic concentrate is then reground to the final grind size of P80 25 µm, which is required to achieve proper awaruite liberation. A further magnetic separation step processes the reground material.
Flotation and product dewatering
The fine magnetic concentrate is subjected to flotation. Based on testwork, a final flotation concentrate grade of 63.4% Ni can be achieved. The final concentrate is dewatered and briquetted into the final saleable product.
Ramp-up considerations
The first year of operation is assumed to be a ramp-up year with mill throughput at 75% of nominal capacity. Year 22 is also assumed at 75% of nominal throughput to account for construction and tie-ins to incorporate the added grinding capacity for Phase 2.
Key reported parameters
| Parameter | Value | Basis |
|---|---|---|
| Nominal processing capacity | 120,000 tpd (43.8 Mtpa) | PEA design |
| Primary grind size (Phase 1, Years 1-21) | 300 µm | Dictated by TSF design |
| Primary grind size (Phase 2, Year 22+) | 170 µm | BBA high-level analysis |
| Final flotation concentrate grade | 63.4% Ni | Testwork |
| Final grind size (P80) | 25 µm | Required for awaruite liberation |
| Crushing plant utilization | 70% | Design assumption |
| Downstream plant utilization | 92% | Design assumption |
| Equipment design factor | 15% above nominal | Design assumption |
| Ramp-up throughput (Year 1 and Year 22) | 75% of nominal | PEA assumption |
| DTR Ni recovery equation | DTR Ni Rec % = (-0.0376 × Primary grind size µm) + 95.93 | Developed from testwork |
Project website: https://fpxnickel.com/projects-overview/baptiste-nickel-project/
Technical qualifications
The recovery equation for DTR (Davis Tube Recoverable) Ni recovery was developed from testwork performed using samples from the Baptiste Deposit. The final flotation concentrate weight recovery is calculated based on the targeted final grade of 63.4% Ni, which is assumed for this PEA. The 170 µm primary grind size target for Phase 2 is based on a high-level analysis by BBA that estimated increased capital and operating costs for improved DTR Ni recovery.
Source: NI 43-101 Technical Report, PEA of the Baptiste Nickel Project, September 2020. Processing sections as cited.
