Influence of slag particle size on performance of ceramic bricks containing red clay and steel-making slag

Abstract

To manage steel-making slag (SS) produced as industrial waste and conserve ceramic raw material resources, it is significant and sustainable to develop new ways of using SS. In this study, a novel ceramic brick was prepared using SS and red clay. The influence of SS particle size and sintering temperature on the sintering process and final properties of the red clay ceramic bricks was investigated. The water absorption capacity and compressive strength of these samples were analyzed. The results showed that the water absorption rate of the samples decreased with decreasing slag particle size and that the compressive strength of the sample reached its peak value at a moderate SS particle size (<0.075 mm) and sintering temperature (1150°C). The effect of SS particle size on the properties of the red clay ceramic bricks was investigated by analyzing the liquid phase and crystal structure. In addition, the relationship between SS particle size and activation energy of the sintering reaction was established, which is expected to provide useful information for the design of a sintering schedule for red clay–SS ceramic tiles with a certain SS particle size. We demonstrated a process for preparing a new type of ceramic brick that exceeds the specifications for pedestrian paving applications, while minimizing problems related to waste SS disposal.