Modern Mining October 2022

profitability

minerals, as well as depressants and frothers suit able for PGM ores. More recently, Axis House has been putting the AM810 reagent through its paces at a PGM mine in Brits in the Northwest Province, specifically targeting the oxidised minerals. The mine, which has been on care and maintenance since 2013, recently re-engineered the operation to be more cost effective. As part of its drive to keep costs to a minimum, the PGM and chrome miner was one of the first in line to test the AM810 reagent at its flagship opera tion and has since been achieving excellent results. “Aside from having undertaken extensive lab tests on the material sourced from the miner’s tail ings storage facility, Axis House also undertook plant trials, over a few weeks, and is now running exten sive trial tests spanning up to two months. We are confident of being able to improve on the first set of grades, which have already delivered impressive results,” explains Stubbs. Providing some background to the project, Oostendorp says that the processing plant at the mine consists of two separate plants – one target ing a more abrasive application while the scavenger circuit aims at a much finer material. “Owing to the low PGM basket price in 2012, the miner was forced to shut down the plant as it ceased to be economical. However, following improved platinum prices, the mine recently restarted and with the AM810 and DPG-12 delivering outstanding results, the scavenger plant will no longer sit idle but ramp up production and hence increase profitability for the mine.” Axis House is also in the process of developing a suitable selective frother at the Cape Town laboratory, to further minimise any Chromite entrained to the PGM concentrate. In addition to being trialled at the chrome and PGM operation, the suite of PGM flotation reagents is also being tested on ore from platinum produc ers in the area, including at a number of mid-tier and

junior miners as well as by a large-scale operator. Collectors, frothers and flocculants are the main products currently being tested. Explaining the testing process, Stubbs says that products are initially tested at both the client’s lab and at Axis House’s facilities in Cape Town and Johannesburg, followed by pilot plant trials and then onto full-scale plant, for a short period of a few weeks and then by an extensive trial lasting up to two months.

A microflotation unit being put to work.

Below left and right: Axis House’s new suite of PGM flotation reagents is being tested on ore from platinum producers.

October 2022  MODERN MINING  9