Development of refractories for the pyro-processing (heat-based) industry in Nigeria through the evaluation of mixtures of Enugu Iva-Pottery clay, Nsu-clay and palm kernel shell waste

Abstract

The energy demand is on the global increase as the world economy is increasing steadily. Hence, the need to develop energy-saving technology with local raw materials and abundant waste materials becomes paramount. The mixtures of Enugu Iva-pottery clay, Nsu clay and PKS were evaluated to improve the quality of locally produced refractory for pyro-processing industries. The chemical and mineralogical composition of the PKS and the clay were determined. Eight recipes were made by varying PKS with quartz from 5 to 35% and produced by the wet pressing technique, then fired to 1200 °C and 1300°C respectively. The mechanical properties were determined by the Modulus of Rupture test, also, the bulk density, linear shrinkage, total shrinkage, apparent porosity, water absorption and thermal efficiency tests of the produced refractories were ascertained. The recipe with 15% PKS sintered well at 1300°C and gave the best optimum results of 1.76g/cm3 bulk density, 6.49% linear shrinkage, 21.384% apparent porosity, 20 cycles of spalling tests at 1300 °C. The results comply well with the standards of refractory properties. The PKS additives have shown significant improvement in the properties of the locally produced refractories and waste control; hence, can promote sustainable development of the local pyro-processing industry.