Black Rock’s Mahenge graphite project in Tanzania continues to impress, with the latest pilot plant metallurgical test work validating and exceeding the initial results returned from Canada last year.
The test work was undertaken by engineering, procurement and construction, or “EPC”, partner Yantai Jinyuan, at its processing facility in China.
Steady state results returned from an oxide ore run through the plant produced a final concentrate grade of 98.7% total graphitic carbon, or “TGC”, at a recovery of 95.5%, with 56.2% of the particle distribution coming in above 100 mesh size, which commands premium prices.
Black Rock CEO John de Vries said: “We … have replicated and enhanced our industry leading processing performance from our second substantial pilot plant run. The 18-tonne pilot plant in China built on the earlier 90 tonne pilot plant run in Canada.”
“Importantly we were able to deliver a higher specification material of +98% TGC while maintaining our target of +60% greater than #100 mesh. We also increased our recovery rate to 95.5%. All of this was delivered in front of our customers, partners and potential investors.”
“A key objective of the plant operation was to enable representatives from China, Korea and Japan the opportunity to validate the remarkable metallurgy that characterises our Mahenge graphite (ores). We are pleased to say feedback was very positive and we look forward to progressing discussions resulting from the review.”
The pilot plant results will be included in the front-end engineering design, or “FEED”, process currently being completed by Yantai, which is due for delivery in the next few months.
The company’s large Mahenge graphite project in Tanzania might be the answer for the emerging expandable graphite sector’s insatiable hunger for coarse flake products, with such a high proportion of the deposit’s processed ores reporting into that high-value category.
Whilst many operators are struggling with skinny margins rarely exceeding USD$200 per tonne for their graphite products, Black Rock’s DFS for Mahenge shows exceptional margins that exceed USD$800 per tonne for its high-quality large flake concentrates.
The former operators are lucky to have 10% or 20% of their product reporting to large graphite flake sizes, which exemplifies the uniqueness of Black Rock’s ores.
The recent pilot plant test in China effectively validates Black Rock’s Mahenge mine processing flow sheet design and the high-quality character of its concentrated ore products.
For Black Rock, it’s all about locking in an appropriate basket price for its quality graphite products, now that the volumes have been agreed with its offtake customers.
Graphite concentrates reporting below 100 mesh size will be processed for battery anode precursors in dedicated facilities to provide materials for independent battery performance testing, with results of this work expected in late May, the company said.
The recent test work results endorse the value of Black Rock’s ore stream from its exciting Mahenge project in Tanzania.
Black Rock released its impressive DFS for the project in October last year, estimating a 32-year project life with a post-tax NPV of USD$895m and IRR of 42.8%.
The CAPEX also looks manageable with only USD$115m required to build the processing plant for phase one.
Current ore reserves stand at 70 million tonnes grading 8.5% TGC, that Black Rock’s DFS says should result in 250,000 tonnes of graphite product processed per annum for nearly 25 years.
In February this year, the company said that its two contiguous mining licences at Mahenge had been approved by the Government, providing further support for project start-up.
By Matt Birney
