EVALUATION OF ALUMINOSILICATE REFRACTORY MADE WITH FIRECLAY AND SECONDARY ALUMINIUM DROSS

Abstract

The aluminosilicate refractory material was studied in mixtures of fireclay, chamotte, and secondary aluminium dross. The high content of dross waste was blended, approaching 80% by weight, with fireclay to investigate the influential factors on mould capacity and physico-mechanical properties, which were evaluated based on bulk density, porosity, volume change, water absorption, and cold compressive strength. The aluminium dross, characterized by high porosity and a particle size distribution with a significant proportion under 0.3 mm, significantly influenced moulding parameters, requiring a moisture level of up to 18% and resulting in a reduced bulk density of specimens. The results also indicated that an increase in the amount of aluminium dross raised the porosity and water absorption, but decreased the compressive strength. The performance of the specimens was significantly improved when the maximum size of the aluminium dross particles was reduced from 2.5 mm to 0.3 mm, and the firing temperature was increased from 1400 ˚C to 1450 ˚C. Consequently, the water absorption decreased from 16.6% to 23.5%, and the compressive strength increased by 78.4% to 140%, particularly eliminating the volume-expansive phenomenon in specimens containing the dross waste. Moreover, the microstructure of specimens was also characterized by X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM) techniques.