Blackstone Minerals Ltd (ASX:BSX, OTCQX:BLSTF) says it is making exciting progress on metallurgical test work currently ongoing at its Ta Khoa Refinery Project (TKR) and Ta Khoa Nickel Project (TKN) in Vietnam’s Son La Province in preparation for their respective definitive feasibility studies (DFS).
TKR Downstream Project
The company has made progress on the test work program, including:
- completion of bench test work program: The hydrometallurgical bench test work program successfully confirmed the improved DFS process flowsheet. Data collected during the bench test work program has been used to update the TKR plant design criteria;
- design, procurement, and assembly of piloting equipment: Extensive work has been completed between Blackstone and the DFS consultants Wood and ALS to develop a pilot campaign that is fit for purpose and aligns with the DFS flowsheet;
- successful commissioning of piloting equipment: ALS has successfully assembled the TKR flowsheet and commissioned all unit operations from mixed hydroxide precipitate (MHP) re-leach through to the production of battery grade metal sulphates. The pressure oxidation leach flowsheet will be commissioned by end of August 2022; and
- successful operation of MHP to metal sulphate from third party MHP: Blackstone has successfully piloted the TKR flowsheet, confirming its ability to process third-party MHP to battery grade metal sulphates.
The TKR program will next pilot nickel concentrate feed, sourced from the mine site and third-party nickel sources, to produce MHP for conversion to battery grade metal sulphate in preparation for precursor cathode active material (pCAM) processing. The program is expected to be completed in the fourth quarter of 2022.
POX leach autoclave
TKN Upstream Project
A range of activities are underway for this project, including:
- piloting and bench test work advancing: Blackstone has completed the construction of a pilot plant at the mine. Piloting is underway and will continue through the second half of 2022. Bench testing is undertaken in the metallurgical laboratory at the mine. Comminution test work commenced this month on a range of core samples obtained from a drilling program completed in July 2022. The program of works with ALS Metallurgy in Perth is anticipated to be completed during the second half of 2022, in addition to variability test work for flotation flowsheet validation, dewatering and filtration;
- site visits to Vietnam: DFS consultant GRES has made several trips to the mine site to support the ongoing metallurgical program and work with the site team to design and plan the upcoming test work programs in Vietnam and Perth;
- validation of approach: GRES has validated the suitability of the in-country facilities and the piloting equipment for providing process design data for the DFS; and
- further piloting: Additional re-grind and flotation piloting equipment has been sourced from relevant equipment vendors.
TKN pilot plant
Green Nickel leader
Blackstone managing director Scott Williamson said: “It is very exciting to see the hard work from our Blackstone team and metallurgical partners to successfully design and pilot the respective Upstream and Downstream DFS flowsheets.
"The success of these respective pilot programs demonstrates our commitment to develop competitive and flexible flowsheets to service the future needs of the battery market.
"We will continue to work with our technical and strategic partners to ensure Blackstone is a leader within the Green Nickel™ battery market.”
Carbon-rich
A study by the University of British Columbia (UBC), engaged by Blackstone to assess the project’s ability to capture carbon via carbon mineralisation, has returned exciting results, where waste and tailing materials have been shown to be rich in carbon absorbing minerals, such as brucite and hydrotalcite minerals, and is capable of capturing and storing up to 8.3 grams of CO2 per kilogram of tailings.
“Technology-ready approaches to mineralise CO2 in mine tailings take advantage of the presence of highly reactive gangue minerals which are present in significant abundance in samples from Ban Phuc. Testing of these samples demonstrates the potential for enhanced carbon capture and storage," said UBC’s Dr Greg Dipple.
The final report from UBC is expected next month but initial findings support Blackstone’s ambition to deliver a net-zero emission project, further strengthening its vision to be a Green Nickel™ producer.