Towards zinc metal at McArthur River

A conceptual design for producing 300,000 tpa zinc directly from McArthur River bulk concentrates is presented. It takes into account the availability of natural gas and the associated increasing importance of Darwin as a hub for natural gas from the Timor Sea. The Albion process for producing zinc at the mine site has been reported as unsuitable because of the costs involved in electricity generation. Clearly, this applies to all hydrometallurgical processes employing electrowinning. What is needed is a radical rethink of pyrometallurgical treatment. Emphasis is given to what has become known as the “Warner process”, modified to yield considerable savings in energy requirements by removing the need for an air separation and massively increasing the intensity throughout. Particular attention is given to the condensation of zinc without fog formation, followed by in-line refining to SHG. The principal reactor involved is identical in size and vacuum pumping system to the Port Talbot (UK) recirculating degasser for producing ultra low carbon steel.