Improving air quality at a New Caledonia mine

Improving the air quality of their Doniambo nickel smelter was a big focus for New Caledonian miner Société Le Nickel (SLN) - something they achieved through an award-winning baghouse (air filter) design.

Société Le Nickel (SLN), one of New Caledonia's largest mining companies, initiated a number of environmental improvement projects at their Doniambo nickel smelter under the umbrella 'Doniambo Propre' (Clean Doniambo).

One of these projects, which required Beca's expertise, involved investigating options for cleaning up off-gases from the ferronickel desulphurisation 'shaking stations' at their smelter site in suburban Nouméa.

Using our IDEAS™ dynamic 3D technology while investigating the pressure drop of potential gas duct configurations, it became apparent this modelling could also investigate heat lost to the direct surrounds of the ducts. If these gas emissions could be reliably cooled to 250°C, a baghouse structure would then become a viable and cost-effective solution.

The further use of IDEAS™ simulation proved the efficacy of a baghouse design, enabling Beca to engineer a system that required no special heat transfer equipment or air dilution. This avoided the need for a more expensive, high maintenance Electrostatic Precipitator solution.

Once this design solution was identified, Beca oversaw construction by a team of local contractors, including the removal and refit of two existing 50 metre high stacks to accommodate the new duct tie-ins and isolation dampers. All this work was completed on schedule in a live environment around existing smelter operations, with no lost-time or safety incidents over 15,000 man hours on site. The Doniambo smelter now enjoys better air quality outcomes which can only benefit the broader community.