Efficiency of a hybrid constructed wetland system in treating industrial wastewater: a path to sustainable phytoremediation and agricultural reuse

Industrial wastewater treatment is a challenging process, but the most challenging is finding a cost-effective natural treatment. The present study evaluates the efficiency of an Integrated Constructed Wetland (ICW) system for treating industrial wastewater, focusing on its performance over a 12-day Hydraulic Retention Time (HRT). The HCWs were planted with specific vegetation combinations, aimed at enhancing pollutant removal rates. Results demonstrate the efficacy of both systems in removing various pollutants, including Total Suspended Solids (TSS), Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Kjeldahl Nitrogen (TKN), and Orthophosphates (OP). The HCWs exhibited substantial removal rates for heavy metals, with percentages ranging from 64% to 70% for Zn, 45% to 54% for Cu, 50% to 58% for Ni, 47% to 54% for Fe, 44% to 59% for Cr, and 34% to 36% for Pb. Additionally, the HCWs effectively removed enteric bacteria, including Mesophilic Flora (MF), Faecal Streptococci (FS), Total Coliforms (TC), and Faecal Coliforms (FC) with total removal that exceeded 95%. Results indicate that the average concentrations of all analyzed pollutants were well below these regulatory thresholds, underscoring the efficacy of the HCW model as a viable solution for industrial wastewater treatment.