Ausmelt at Whyalla
Ausmelt has modified the plant, located 2km north of Whyalla, previously used by SASE for use as a zinc recovery operation. The source of zinc feed are residues from Nyrstar Ltd's Australian zinc operations.
Ausmelt will smelt the residues, along with coal and fluxes, to separate the zinc from the residue. There will be three products, high grade zinc oxide, slag and gypsum. The zinc oxide will be shipped back to Nyrstar so they can recover the zinc as metal. The slag, which has had the valuable metals stripped out of it and which is inert, will be stockpiled on the Ausmelt site. Gypsum is produced when sulphur dioxide is scrubbed from the smelter gas in order to meet EPA regulations for emission limits. The gypsum will be stored in a lined pond on site.
The residues contain low levels of lead and Ausmelt is spending most of the project’s capital on containment of emissions. Almost all the lead will leave the site in the main product to be processed at Risdon from where it will enter the mainstream use of the metal. The very small amount left will be sealed in the furnace slag at levels well below safe storage limits.
Ausmelt has built a sealed shed to store residues. This shed has its own baghouse which is kept under negative pressure in order to contain dust. A sealed system to contain the product oxide has been established, which also operates under negative pressure, with its own baghouse. Product is loaded directly from the sealed system into bulker bags which are tied shut before leaving the product building.
Residues are delivered to site by covered trucks and product is taken away in covered trucks. These trucks will go no further south than the Norrie Rd extension. The plant includes a contained wash down station to make sure that trucks are clean when they leave site.
Click here to view a PDF of the Whyalla Smelter (8.0 Mb)
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