Reimagining biofiltration for sustainable industrial wastewater treatment

Abstract The discharge of wastewater from large-scale industrial facilities continues to pose serious environmental and public health risks due to the presence of complex mixtures of organic pollutants, pathogenic microorganisms, suspended solids, and hazardous trace metals. Conventional treatment systems often fall short in effectively addressing these diverse contaminants, especially under fluctuating load conditions. This study explores the potential of biofiltration-based treatment systems, including re-engineered wetlands, fixed-bed biofilters, fluidized-bed reactors, and biofilm-supported units, as sustainable and adaptable alternatives for industrial wastewater remediation. The paper critically evaluates their mechanistic underpinnings, design principles, and pollutant removal efficiencies across varied industrial contexts. Key operational parameters such as media selection, hydraulic loading, biofilm dynamics, and system maintenance are discussed in detail. Comparative performance analysis against national regulatory discharge standards for COD, BOD, TSS, and heavy metals underscores the capability of biofiltration systems to meet compliance targets while offering environmental co-benefits. The findings highlight biofiltration as a promising pathway for integrating ecological design into sustainable industrial water management frameworks. Graphical abstract