An innovative design and development of up-flow compact constructed wetland for sewage treatment.

Abstract

The growing demand for sustainable sewage treatment requires technologies that overcome the limitations of energy-intensive and chemical-dependent systems. This study presents an innovative solution addressing both environmental and operational challenges with the design and development of an Up-flow Compact Constructed Wetland (UCCW) based Sewage Treatment Plant (STP). This system integrates preliminary, primary, secondary, and tertiary treatment units into a single setup. The performance of UCCW based STP was evaluated over 720 days under different Hydraulic Retention Times (HRTs), considering seasonal variations in both rectangular and circular configurations. The system achieved significant pollutant removal as Total Suspended Solids (96%), Chemical Oxygen Demand (86%), Biochemical Oxygen Demand (90%), Total Nitrogen (70%), Total Phosphorus (65%), and Fecal Coliforms (99%) at a 36-h HRT. These parameters meet discharge standards, except FC, which requires disinfection for safe reuse and recycling. Further, Response Surface Methodology (RSM) and Monte Carle Simulation of UCCW based STP confirmed optimal and reliable performance at a 36-h HRT. Compared to conventional treatment technologies, the UCCW based STP demonstrated higher efficiency, a smaller footprint (1m²/KLD), better operational flexibility, cost-effectiveness, and minimal operation & maintenance to make it sustainable for decentralised treatment.