Comparative investigation of eggshell’s particle size distribution as foaming agent for manufacturing glass foam

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Abstract

Various waste materials have been repurposed as secondary raw materials for producing environmentally friendly building products. One type is glass foam which is a thermal insulation material. To produce glass foams, glass powder is mixed with a foaming agent and treated at temperatures higher than 600 °C to inflict gas formation. An essential step in preparing the raw materials is grinding them to an optimal particle size range. Eggshells, due to their high calcium carbonate content, can serve as a foaming agent. However, their plate-like structure makes it challenging to accurately determine size parameters. This study presents a comparison of two different analytical methods—laser diffraction (LD) and dynamic image analysis (DIA). The results show that as grinding time increases, particle size decreases and sphericity improves. Particle breakage begins after 16 minutes achieving optimal size at 30 minutes. Consistency in measurement methods is found at 60 minutes of grinding as particles become more compact and spherical.