Preparation of Aluminum Dross Microporous Bricks and the Pore Formation Mechanisms

Considering the harmful impact of the disposing of secondary aluminum dross (SAD) on the environment, we suggest producing aluminum dross microporous bricks (ADMBs) from SAD as a solution. These bricks possess thermal insulation properties, and we conducted research to study the impact of carbon powder particle sizes and sintering temperatures on their compressive strength, thermal conductivity, bulk density, and porosity. Additionally, we examined the mechanism of pore formation in the ADMBs. The results showed that the best overall performance of the prepared ADMBs was achieved with a porosity of 55.87%. There are three main types of internal pores. The first type is formed by the removal of carbon powder, which is generally formed near the surface layer of the ADMBS, and the hole size is related to the particle size of the carbon powder. The second type is formed by the expansion of holes, generally formed in the center of the ADMBS, the cavity size of which is related to the sintering temperature. The third type is formed by the expansion of cracks and is generally formed near the location where the original carbon powder was present.