Physical and Microscopic Characterization of Thermal Treatment Products of Plant Waste for Recycling in Sustainable Construction

Organic plant waste is a significant source of environmental pollution, necessitating proper disposal methods. One sustainable approach is recycling this waste for beneficial applications. Recent studies have explored the potential of incorporating organic waste into construction materials. In this study, selected municipal organic wastes—orange peel, corn cob and husk, pineapple leaf, and garden grass—were characterized and evaluated for their suitability in mortar and concrete production. A preliminary assessment involved substituting various percentages of sand with these organic residues in mortar mixtures. Among the tested materials, garden grass yielded the most promising results, exhibiting compressive strengths comparable to the control sample after seven days of curing. Based on these findings, mortar and concrete samples were prepared with 5% and 10% volumetric replacement of sand by grass. After seven days of curing, mortar samples with 5% and 10% grass replacement achieved 88% and 74.6% of the control sample’s compressive strength, respectively. Similarly, concrete samples reached 87% and 85% of the control strength after 28 days of curing. These results suggest that recycling garden grass as a partial sand substitute in mortar and concrete is a viable option. However, further research is necessary to determine the optimal substitution percentage and to evaluate long-term durability, ensuring safe and effective implementation in construction applications.