Enhancing Thermal Performance of Autoclaved Aerated Concrete (AAC) Incorporating Sugar Sediment Waste and Recycled AAC with Phase Change Material-Coated Applications for Sustainable Energy Conservation in Building

This research focuses on the integration of waste materials derived from sugar sediment and recycled AAC into the manufacturing process of autoclaved aerated concrete (AAC) to enhance its physical, mechanical, and thermal characteristics. Furthermore, the investigation explores the prospect of augmenting the thermal efficiency of the AAC composite by applying different quantities of paraffin phase change material (PCM) coatings to its external surface. Throughout the thermal testing phase, temperature control was consistently maintained at three distinct levels: 40 °C, 50 °C, and 60 °C, facilitated by a heater serving as the thermal source. The investigation unveiled that the optimal composition encompassed a 10% by weight replacement of sand with recycled AAC content. This formulation resulted in a peak compressive strength of around 5.85 N/mm 2 , along with a maximum tobermorite phase ratio of 25.5%. The elevated strength is directly associated with the heightened crystalline nature of the tobermorite phase. The most favorable configuration incorporated a 20 g PCM-coated material, demonstrating remarkable outcomes, including an extension of the time lag by about 55%, a reduction in the decrement factor by around 56.4%, as well as a substantial reduction in room temperature of roughly 15.8% compared to standard AAC without PCM coating, all at a stable temperature of 60 °C. The integration of sustainable waste materials and PCM technology, as illustrated in this study, notably contributes to resource conservation and the advancement of energy-efficient architectural practices.