Comparison of the efficiency of two wastewater treatment schemes using Subsurface Flow Wetlands for contaminant removal

Resumen

Abstract – Effective wastewater treatment is essential to meet environmental and public health standards. This study evaluates the performance of two wastewater treatment schemes using Subsurface Flow Constructed Wetlands (SFCWs) for contaminant removal under varying hydraulic retention times (HRTs) of 3, 5, 7, 9, 11, 13, and 15 days. The analyzed parameters include total coliforms, fecal coliforms, dissolved oxygen (DO), suspended solids (SS), chemical oxygen demand (COD), biochemical oxygen demand (BOD5), ammonium nitrogen, total nitrogen, nitrate nitrogen, total phosphorus, and orthophosphates. The influent wastewater exhibited high levels of organic matter, nutrients, and microbial contamination. Both schemes achieved significant reductions in all evaluated parameters, with varying efficiencies depending on the HRT and treatment scheme. The results underscore the effectiveness of both treatment schemes in achieving substantial contaminant removal, meeting water quality standards, and providing valuable insights for optimizing HRTs and improving treatment outcomes. This study contributes to the development of sustainable wastewater management strategies, particularly valuable for regions with limited resources or high environmental vulnerability. Keywords – subsurface flow constructed wetlands, wastewater treatment, hydraulic retention time, contaminant removal, water quality management.