Rosh Pinah commissions new SAG mill as mine expansion nears completion

The Rosh Pinah zinc mine in southwestern Namibia is set to double its processing throughput after completing the commissioning of a new SAG (semi-autogenous grinding) mill.

On Monday, private equity firm Appian Capital Advisory, which holds a 90% interest in the mine, announced the successful commissioning of the SAG mill, which represents the final major processing component of the mine’s planned expansion.

Situated in the Namib Desert, roughly 20 km north of the Orange River, the zinc-lead mine has been operating since 1969, establishing itself as a cornerstone of the local mining town, also named Rosh Pinah.

The ongoing expansion — known as RP2.0 — comprises further development of the underground mine, including the newly developed WF3 portal and decline, as well as the construction of new surface facilities. 

The new SAG mill, which replaces the existing ball mill as part of the new surface infrastructure, is expected to double the mine’s processing throughput to 1.4 million tonnes of ore per annum from 700,000 tonnes currently following ramp-up.

In addition to an expanded processing capacity, the SAG mill is also designed to enhance the plant’s ability to treat harder ore types, which become more prevalent as mining progresses.

Its commissioning brings the full RP2.0 circuit into operation as an integrated system, incorporating the paste fill and water treatment plants and expanded flotation (entire new zinc circuit), thickening and filtration capacity, Appian stated in the press release.

The expansion extends the operation’s economic life and improves resource utilization across the orebody, strengthening Rosh Pinah as a long-life base metals project in Namibia, the firm also said.

According to Appian, the project is advancing on schedule and on budget, with overall construction progress now surpassing 95%.

“Commissioning the SAG mill marks the completion of our core processing infrastructure and reflects the quality of execution by the RPZ team throughout the RP2.0 program,” stated Ignacio Bustamante, Head of Base Metals at Appian.

“With the full circuit now operational, the project is positioned to achieve a step-change in production output,” he added.