RPZ commissions 7 m SAG mill: comminution upgrade lens for process engineers
Reviewed by Joe Ashwell
First reported on International Mining – News
30 Second Briefing
Rosh Pinah Zinc in Namibia and Appian Capital Advisory have commissioned a new 7 m diameter Metso SAG mill, replacing the existing ball mill as the final major processing component of the RP2.0 expansion. The mill’s start-up completes the core plant upgrade, enabling a shift to single-stage SAG grinding and simplifying the comminution circuit. For process engineers, the change should allow higher throughput and coarser primary grind, with knock-on effects for downstream flotation performance and energy use.
Technical Brief
- Metso-supplied semi-autogenous grinding mill specified with 7 m shell diameter for RP2.0.
- Commissioning marks completion of the last major process-plant item in the RP2.0 flowsheet.
- For similar brownfield zinc operations, single large SAG units are increasingly preferred over multiple smaller ball mills.
Our Take
Taken together with the earlier commissioning of the process water treatment plant and Namibia’s first paste backfill plant at Rosh Pinah, the RP2.0 expansion is emerging as one of the more fully integrated underground zinc flowsheets in our database, with upstream, water and backfill upgrades being executed in close succession.
Appian Capital Advisory’s repeated appearance across the Rosh Pinah zinc, lead and silver upgrades signals a deliberate push to reposition this Namibian asset as a longer-life, lower-dilution operation, which may improve its resilience against zinc price volatility compared with smaller, single-stream African zinc mines in our coverage.
Within our zinc-tagged mining stories, relatively few African operations are simultaneously adding large-diameter SAG milling and paste backfill; this combination at RP2.0 is likely to support tighter stope design and higher throughput, which can put competitive pressure on older zinc-lead mines still reliant on open stoping with rockfill or delayed backfill cycles.
Prepared by collating external sources, AI-assisted tools, and Geomechanics.io’s proprietary mining database, then reviewed for technical accuracy & edited by our geotechnical team.
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