Refractory Clays & Chamotte
Refractory Clays & Chamotte will comprise 12.6% of Kaolin products and 1.1% of all products produced by the Project at full production levels.
The refractory properties of clay are a function of its alumina content and the level of impurities present. The extremely low alkali content of certain kaolin clays makes them important in the manufacture of super-duty firebrick with enhanced hot load bearing properties. Bauxite is sometimes added to kaolin to raise the alumina of the finished product.
Production of refractory kaolin from separated kaolin is extruded into briquettes and dried in a kiln to 1% moisture content, prior to calcination. After calcination, the blocks are crushed and screened to standard range of aggregates.
The iron and steel industry is by far the leading consumer of refractories. There is a growing trend to replace traditional clay refractories with newer products that use chrome, graphite, and zirconia, and hence there is unlikely to be substantial market growth in the future. Exports for this item are good.
The Shinagawa plant in Unanderra manufacture refractory bricks and castables for the BHP Steel making industry of Port Kembla and import around 10,000 tonnes of refractory clays from the U.K. annually. Additional sales are expected from smaller producers of industrial and household refractory items such as:
• Cement refractories,
• Refractory crucibles,
• Industrial ceramics,
• Graphite foundry accessories, and
• Refractory monoliths.
SCM kaolin has excellent refractory properties, i.e. high Pyrometric Cone Equivalent (PCE), low alkalis, and high purity. It would serve as a suitable raw material for refractory kaolin production and become a full import replacement.
The price of calcined kaolin used for use in refractory bricks ranges from AUD450-600.
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