As an enabler to support Namdeb’s Life of Mine extension to 2042, a decision was made to construct the Alternate Feed Stream (AFS) as a second feed point for run of mine ore into #3 Plant Treatment facility situated within the Southern Coastal Mine (SCM).

The AFS will enable an additional 280 tons per hour (tph) throughput into the treatment plant, and is designed to effectively treat diamondiferous gravel sourced from clay rich areas, which would cause extensive blockages and downtime in the existing plant front end.

The pre-feasibility study started mid 2020 as one of the outcomes of the Southern Coastal Extension Project study (SCEP) with the aim to provide a solution to extend the Life of Mine at Namdeb beyond 2022. Construction of the AFS started in April 2022, and is envisaged to be completed during the 3rd (third) quarter of 2023, whilst the full handover to Operations is planned for November 2023.

Incorporating innovation and technology is a crucial aspect of achieving desired operational efficiencies and thus key design features of the feed stream include:

• Front-end tipping bin with a low-profile SAMSON feeder (to control the material feed volume) and vibrating Grizzly screen (fitted with high pressure spray water) to remove oversize material and flush material into the downstream process.
• Scrubber positioned directly downstream from the scalping screen to properly “break up” and wash the product gravels of all remaining clay.
• Vibrating wet sizing screen with high pressure spray water to further separate DMS feed (Diamondiferous) gravel from oversize and undersize material.
• A series of belt conveyors, to feed the DMS product material to existing DMS stockpile and oversize material to the existing crushing stockpile respectively.

ADP Namibia, the EPCM management contractor is responsible for the project management, procurement, engineering, and construction management of the plant, whilst K Neumayer Civil Contractors is responsible for earthworks, civil/concrete works and remaining structural and mechanical installations.

Another local company, West Coast Automation Systems, is responsible for the electrical and instrumentation installations as well and software programming.

The project prides itself with an exceptional safety record, and whilst the project is 95% (percent) complete to date, 186,000 Lost Time Injuries (LTI’s) free manhours have been achieved. This is a clear testimony that safety, one of Namdeb’s foundational values, is considered a top priority.

This remarkable accomplishment should be attributed to a dedicated collective workforce that remains the strongest link in ensuring the safe construction of the state-of-the-art treatment facility, and this certainly adds a solid impetus to achieve Namdeb’s vision of becoming the pride of Namibia’s mining to 2050 and beyond!

Contributed by Namdeb