DEVELOPMENT OF REFRACTORY BRICKS FROM LOCAL RAW MATERIALS

Abstract

Aluminosilicate refractory bricks for lining melting furnaces were produced from kaolin. Raw kaolin was processed and refined to remove impurities that may lower the refractoriness of the bricks. Part of this was thereafter used for the production of grog. Samples dimensioning 25.4 x 50.8 x 101.6mm were moulded from varying ratios of processed kaolin and grog mix using 18% tempering water. These were dried naturally in air and then in an oven at 120°C and fired at different temperatures ranging from 1000 to 1500°C. The samples were thereafter tested for such properties as apparent porosity, volumetric drying shrinkage, volumetric firing shrinkage, thermal shock resistance, cold compression strength and refractoriness. Results obtained indicated that the 20:80 grog:kaolin mix possesses good refractory properties for lining melting furnaces. Cost comparison of lining furnaces with bricks produced using existing and the new system was undertaken. The new system was found to cost 67% of the existing system.