EFFECT OF ADDITIVES ON REFRACTORY PROPERTIES OF SOME SELECTED CLAY DEPOSITS IN NIGER STATE, NIGERIA

Abstract

In metallurgical industries the quality of refractory clay depends largely on the refractory properties of clay and proper selection of clay affect these properties which include Porosities, Compressive strength, Linear shrinkage, Thermal shock resistance, and refractoriness. This gives need on the improvement on some properties of selected Nigerian clays. Clay collected from Bida, Chanchaga, Kpakungu and Maikunkele areas of Niger State were analysed to determine the chemical composition of the clays samples and raw clay were beneficiated and mixed with additives which include ash of Sawdust, Rice husk and Cornhusk in a ratio of 5, 10, 15, 20, 25 and 30 % weight to produce clay bricks which were subjected to tests to determine the effect of the additives on the refractory properties of the clay samples. The result revealed Bida clay increase in porosity from 16.64 % to 35 %, Chanchaga clay increase in porosity from 9.98 % to 38.38 %, Kpakungu clay increase in porosity from 8.12 % to 33.37 % and Maikunkele clay increase in porosity from 10.50 % to 35 %. Compressive strength of the clay samples were reduced Bida clay reduced in compressive strength from 51.58 N/m2 to 8.63 N/m2, Chanchaga clay reduced in compressive strength from 65.85 N/m2 to 29.11 N/m2, Kpakungu clay reduced in compressive strength from 63.59 N/m2 to 20.55 N/m2, Maikunkele clay samples reduced in compressive strength from 59.06 N/m2 to 18.52 N/m2. The refractory temperature of Bida, Chanchaga, Kpakungu and Maikunkele clay samples were increased from 1410°C to 1480°C, 1580°C to 1620°C, 1550°C to 1570°C and 1650°C to 1690°C at 5%wt of additives. Conclusively it was revealed that the additives has a great influence on improving some refractory properties of the clay samples and encourage consumption of local refractory clay in metallurgical industries.