Development of Refractories from Local Kaolin

Refractories are materials that can withstand high temperatures and chemical attack of slags without failing, they can be classified as acid, basic or neutral; some are also referred to as special refractories; these are very expensive materials, such as zirconia reserved for research purposes (Gilchrist,1977).They are thermal insulators which are used essentially in the metallurgical industries for furnace linings, kilns, nozzles for pouring molten metal, heat exchangers and driers, to mention a few (Hassan, 2001 and Guo, 2004). Refractory materials are extensively used in the metal industries, along with glass melting and other heat treatment operations. The atmosphere in which a refractory is to operate can dictate the materials that can be used in particular applications; for example, graphite refractories can operate at temperatures of up to several thousand degrees celsius under reducing conditions, or oxygen free conditions, such as vacuum. The type of materials that a refractory comes into contact with can also dictate which material will be suitable for a particular refractory purpose.