Thermal Stability and Heat-Resistance Evaluation of Agro-Waste Reinforced Polymer Composites for Gas Processing Facility Applications

Abstract Gas processing and associated energy facilities operate under sustained thermal exposure conditions that require reliable insulation and heat-resistant materials to maintain operational integrity and safety. In Nigeria, most thermal insulation materials used in gas facilities are imported, increasing project costs and exposing operators to supply chain disruptions. This study evaluates the thermal stability and heat-resistance characteristics of a locally sourced agro-waste reinforced polymer composite as a potential non-structural insulation material for gas facility applications. Snail shell powder (SSP), an abundant calcium-rich agro-waste, was incorporated as a particulate reinforcement in a polystyrene (PS) matrix at volume fractions of 5%, 10%, and 15%, with particle sizes of 425 μm, 212 μm, and 106 μm. Composite samples were fabricated using the hand lay-up technique. Thermal stability and degradation behavior were assessed using thermogravimetric analysis (TGA), while flammability behavior was evaluated in accordance with ASTM D635 horizontal burning tests. TGA results indicated that SSP reinforcement delayed the onset of thermal degradation of the polystyrene matrix, with degradation initiating at approximately 380 °C and peak mass loss occurring near 435 °C. Increased SSP content resulted in higher residual char formation at 800 °C, suggesting improved heat resistance and enhanced thermal shielding behavior. Flammability testing showed that burning rates were influenced by filler loading, with lower SSP volume fractions exhibiting reduced burning rates, while higher filler content demonstrated a trade-off between thermal stability and flame propagation characteristics. The findings demonstrate that SSP-reinforced polystyrene composites exhibit improved thermal stability compared to neat polystyrene and show potential as non-load-bearing thermal insulation or backing materials for applications such as pipe insulation systems, instrument enclosures, and cable tray linings in gas processing facilities. This work supports the use of locally available agro-waste materials to enhance supply chain resilience, reduce material import dependence, and promote sustainable material solutions within Nigeria's evolving gas and energy infrastructure.