Case 4 Nickel Smelter and Oxygen Production

The Kalgoorlie niekel mine is about 6 m south of Kalgoorlie, Australia. It is operated by Western Mining Corporation and fed by a modern oxygen plant. Niekel was first diseovered at nearby Kambalda in 1966. By 1970, eoneentrated niekel sulfide ore was being mined and delivered to the Kwinana refinery near Perth. Then, in 1972, a smelter was built near Kalgoorlie so that produetion at the Kambalda mine eould be inereased. 

Dry niekel eoneentrate is brought from the mine by rail and stored in eight 1,000-t silos before being eombined with flux and reeyeled furnaee dust. Eventually, it is fed into Kalgoorlie s flash furnaee where temperatures reaeh 1,350°C (2,500°F). 

In Western Mining s flash smelting proeess, reaetion air is preheated to 480°C (920°F) and enriehed until the oxygen eontent is 24%. The reaetion eharge and eombustion air are mixed, and heat for smelting eomes from the eombustion of fuel oil (some of it present in the flux) and sulfur in the eoneentrate. The proeess yields matte, a refined ore with 44% niekel eontent. 

Batehes of matte are then tapped from the sides of the furnaee into ladles and transferred to eonverters. More flux is added, and air is 

In a business where oxygen plants play a key role in the eost of the end produet, Western Mining needs high proeess effieieneies. This prompted the eompany to seleet a eustom-built eentrifugal eompressor and turboexpander. 

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