Pore Structure Regulation in Refractory Grog with Alumina Content over 45 %

Abstract

Increased alumina content in refractory grog is a product of the grog’s firing and, at the same time, it is a raw material used for the production of dense or insulating, shaped or monolithic refractories. Grog characteristics determine the properties of the final product. The specific characteristics of the grog are therefore optimized to suit the refractory product as close as possible. The basic characteristics determining the nature of the grog include its mineralogical composition, chemical composition, and apparent porosity. The present study focuses on ways of reducing the porosity of a high-alumina grog and thus obtaining a raw material suitable for the production of dense refractory materials. The experiments have shown that it is possible to regulate porosity by using clay with better sinterability and phosphoric acid in the production of grog from claystone with alumina content over 40 %, a minimal Fe2O3 content, a minimal content of CaO and alkali oxides.