PERTH (miningweekly.com) – A prefeasibility study (PFS) for the Ta Khoa nickel project (TKNP), in Vietnam, has estimated that the project could produce 151 000 t of nickel over its 9.2-year mine life.

ASX-listed Blackstone Minerals, which held a 90% interest in TKNP, this week noted that first production was earmarked for 2025, ramping up to a nameplate design of 8-million tonnes a year by 2027.

The project will have a steady state production rate of 18 000 t/y of nickel recovered from 225 000 t/y of concentrate.

Blackstone told shareholders that the outcomes of the TKNP PFS have been integrated into the company’s overall business plan to produce nickel, cobalt, manganese (NCM) precursor products, with the TKNP and the Ta Khoa refinery project (TKR) collectively making up the greater Ta Khoa project.

The economics of the greater Ta Khoa project are underpinned by some 50% concentrate feed for the TKR being provided by the TKNP.

Blackstone noted that the integrated Ta Khoa project modelled assumed a life-of-operation for the TKR of 10.3 years, with TKR having steady state refining capacity of 400 000 t/y, and first production of NCM precursor starting in early 2025.

As only around 50% of total concentrate supply from the TKNP will be used, it will result in some stockpiling of TKNP concentrate, which could result in possible life extension.

The base case project would require a total capital investment of $854-million, and would have a pay-back period of 1.8 years, with average annual operating cash flows estimated at $533-million. Blackstone has estimated life-of-operation all-in sustaining costs of $12 253/t of NCM, and all-in costs of $13 192/t.

The study also estimated a post-tax net present value of $1.99-billion and an internal rate of return of 47%.

Blackstone said this week that it was immediately progressing approval to commence definitive feasibility studies for the TKNP.

Definitive feasibility studies for the TKR will be supported by pilot plant testing, and NCM precursor offtake agreements.

Blackstone is expected to make a final investment decision on the Ta Khoa project by early 2023.