Agricultural Drainage Water Treatment with Metal-Coated Recycled Glass as Filtration Media

Excess nutrient and pollutant loading from agricultural runoff is a key driver of water quality degradation, necessitating low-cost, in-situ treatment solutions. Filtration beds are commonly employed for this purpose, yet reliance on sand as the primary filter medium is increasingly unsustainable. Crushed recycled glass is a promising alternative, though its performance characteristics and potential for surface modification remain underexplored. This study demonstrates that surface modification of crushed recycled glass with iron species improves turbidity removal, with statistically significant enhancements observed for specific treatment conditions (p < 0.05). Modified media also achieved Fe removal of at least 76% without detectable iron leaching. Orthophosphate removal by modified media, while constrained by the analytical limit of quantification and therefore representing minimum estimates, was consistently higher than that of unmodified glass. These findings show that surface modification of recycled glass can enhance contaminant removal, while highlighting the influence of particle size on overall performance, providing a foundation for future studies on its filtration behavior and potential for field applications.