EV Nickel talks Ni, Co extraction at W4

Executive Summary

• EV Nickel Inc. reported strong results from a continuous pilot-scale bioleaching and downstream metals recovery test program on flotation concentrates from its W4 nickel project near Timmins, Ontario.
• The pilot circuit achieved over 90% nickel and cobalt extraction, successfully produced high-purity nickel sulphate (up to 98.2% purity), and demonstrated effective iron removal and magnesium recovery.
• The results validate the technical viability of the company's flotation-bioleach processing flow sheet, positioning it as a low-carbon alternative to traditional smelting and supporting plans for future engineering and economic studies.

Key Details

• Nickel and Cobalt Extraction: Achieved 90.1% nickel and 89.6% cobalt extraction at day 6 of the continuous pilot operation.
• Pilot Operation Duration: The pilot circuit operated continuously for 11 days, followed by five days of batch operation.
• Metals Recovery: Greater than 99% recovery of Nickel (Ni) and Cobalt (Co) as a mixed hydroxide precipitate (MHP) from the pregnant leach solution.
• Product Purity: Successfully produced precipitated nickel sulphate (NiSO4.6H2O) with a purity of up to 98.2%.
• Iron Removal: Effective iron removal of greater than 99% with minimal nickel and cobalt losses.
• Byproduct Recovery: Magnesium was successfully recovered as a saleable byproduct.
• Batch/Semi-Continuous Testing: Ni extraction of up to 98.9% and Co extraction of up to 98.8% were achieved in batch and semi-continuous testing.
• Solids Density: Process is amenable to 15- to 20-per-cent solids density with estimated continuous retention times of four to six days.
• Nutrient Optimization: Bench-scale optimization showed nutrient requirements can be reduced to 25% of baseline levels without materially impacting performance.
• Bacterial Scaling: Indigenous bacterial cultures were successfully scaled up from laboratory volumes to 600 litres.
• Feed Grade: The pilot program utilized blended flotation concentrates grading approximately 6.4% nickel.
• Acid Consumption: The process displayed significantly lower acid consumption compared to other hydrometallurgical extraction processes.
• Recycling: Nickel not captured in the nickel sulphate is recycled back into the MHP circuit for future recovery.
• Design Criteria: Preliminary design criteria were developed for a bioleach circuit based on processing 800 tonnes per day of W4 nickel ore.
• Future Work: The company plans to continue optimization focused on improving oxygen transfer efficiency, increasing pulp density, and refining nickel sulphate crystallization.

Notable Quotes

• "After more than four years of development and testing, the results being reported today demonstrate that EV Nickel is ready to advance towards a full-scale bioleaching facility at the W4 project," said Paul Davis, vice-president, exploration. "In addition, the company is now positioned to work with other project owners to advance bioleaching solutions across the nickel sector."
• "The successful completion of this continuous pilot program is a major technical milestone for EV Nickel," said Mr. Davis. "Achieving over 90-per-cent Ni extraction while also demonstrating a clear pathway to high-purity nickel sulphate reinforces the strategic value of our Shaw Dome project and its potential to supply responsibly produced nickel into the electric vehicle market."