Ann: Blackstone Advances NCM Precursor Pilot Plant Testing, page-24

Blackstone Minerals delivers nickel and cobalt feedstock for start of refinery pilot program

John Miller12:17 Wed 06 Apr 2022 - proactive

"As we progress further into pilot plant testing and feasibility studies, we will continue to advance our engagement and collaboration with potential partners and customers for our vertically integrated development strategy,” says MD.

Blackstone Minerals Ltd (ASX:BSX, OTCQX:BLSTF) has taken another step towards de-risking the start of full commercial-scale operations in Vietnam with nickel and cobalt feedstocks for the Ta Khoa Refinery Piloting Program delivered to the ALS Metallurgical Laboratory in Balcatta, Western Australia.

The contractor is in the final preparation stage to begin the piloting program this month.This step comes as Blackstone continues piloting preparation activities at the Ta Khoa Nickel Project in northern Vietnam, including underground development and successful restart and operation of the Ban Phuc nickel concentrator.

The concentrator restart has included the processing of 1,400 tonnes of disseminated sulphide (DSS) sample ore.De-risking projectManaging director Scott Williamson said: “The Ban Phuc mining, processing and maintenance teams have worked tirelessly to refurbish and recommission the Ban Phuc nickel concentrator.

"He said the company was excited to commence the Ta Khoa piloting program with ALS, as it continued to de-risk the project.“Blackstone is committed to sustainable mining and its development plans to recommence full commercial scale operations in Vietnam.

"As we progress further into pilot plant testing and feasibility studies, we will continue to advance our engagement and collaboration with potential partners and customers for our vertically integrated development strategy.

”Underground developmentThe company completed 541 metres of underground development for the ongoing bulk sample project delivering 2,088 tonnes of DSS ore to the mill for processing.

After processing of 1,400 tonnes of the sample ore, 24.5 tonnes of samples were delivered to ALS Laboratories including:7.5 tonnes of Ban Phuc sulphide flotation product;10 tonnes of sulphide flotation products from Trafigura;6 tonnes of sulphide flotation products from other third-party sources; and1-tonne of Cobalt Hydroxide (from Trafigura) as a low-cost alternative to battery-grade cobalt sulphate.

Flotation samples from Ban Phuc ready for shipment.Mining activitiesIn December 2021, Blackstone was granted approval to recommence mining activities as part of ongoing development of the Ta Khoa Project. Approval was received to perform mining works that will involve completion of ~1,000 metres of lateral development.

To March 29, 2022, the company had completed 541 metres of development, delivering 2,088 tonnes of ore to the surface, and averaging 136 metres a month.

Ban Phuc Nickel ConcentratorThe 450,000 tonnes per annum Ban Phuc nickel concentrator was recommissioned in January 2022. This work was completed by the skilled Ban Phuc operating and maintenance team, many of whom were part of the original team that operated the plant in 2013-16.This plant was placed on care and maintenance in September 2016 and has been meticulously maintained.

The efficiency of recommissioning activities and successful operation of the crushing circuit and concentrator, gives Blackstone confidence in its suitability for treating regional massive sulphide vein (MSV) ore bodies.

Blackstone has the optionality to turn on the Ban Phuc nickel concentrator and process MSV orebodies, particularly in an elevated nickel price environment.

About 7.5 tonnes of Ban Phuc flotation samples were packed and shipped to ALS Laboratories in Perth, ready for the pilot program.Pilot programThe primary purpose of the piloting program is to replicate the full scale TKR flowsheet to confirm preliminary test-work conditions and provide an insight into the operation conditions of the continuous plant.Evaluation of the pilot plant data will help to further develop engineering data required for the TKR design and close gaps from previous test-work.

This pilot plant program is broken up into two phases of the downstream refinery flowsheet: the Extraction Phase and Refining Phase.

The Extraction Phase will consist of four campaigns of between seven to 10 days and will cover the front end of the downstream refinery flowsheet entailing the feed concentrate handling/feed to POX up to the production of MHP.

This campaign's focus is to test the design envelope for the POX Autoclave to maximise extraction of nickel, cobalt and manganese.

The Refining Phase will focus on the second half of the flowsheet, including MHP Releach, electrolyte purification (SX), through to NCM Precursor precipitation and drying. The refining solvent extraction stages will be tested over a combined 34 days.