Innovative Recycling Method for Converting Waste into Thermal Insulating Materials

Several industrial waste streams, particularly fiberglass composites, posed a critical environmental challenge due to their limited recyclability and frequent disposal in landfills. This study presented a novel recycling process capable of converting fiberglass composites into an innovative insulating product. Initially, the waste was comminuted and subsequently was mixed with water and alginate to form a viscous suspension. Through a controlled dripping process, the mixture underwent ionic cross-linking, resulting in the formation of spherical granules. A subsequent sublimation-driven water removal step generated a porous structure, which was essential for thermal performance. Experimental characterization of the material confirmed its good insulating properties, with a thermal conductivity of approximately 0.05 W·m⁻¹·K⁻¹ at 20 °C and a bulk density of about 150 kg·m⁻³, highlighting its potential for applications in sustainable construction and energy-efficient building systems. The recycling process was versatile and could be extended to other mineral-based waste, including glass and bricks. Additionally, a Life Cycle Assessment (LCA) approach was employed to quantify the potential environmental benefits of the innovative thermal insulator in comparison with previously reported insulation foams derived from recycled waste and biopolymers, and conventional insulating materials commonly used in many industrial sectors. The material demonstrated a favorable environmental profile, showing reduced impacts in terms of Global Warming Potential (GWP) and a promising decrease of process energy consumption. This approach not only mitigated landfill accumulation but also added value to industrial waste by creating functional materials with strong environmental benefits.