Speakers
Description
The escalating global demand for sustainable aquaculture practices coupled with increasing environmental regulations necessitate innovative, cost-effective solutions for wastewater treatment and water reuse in African agricultural systems. This study presents a comprehensive evaluation of a pilot-scale horizontal subsurface flow (HSSF) constructed wetland system specifically designed for treating aquaculture wastewater from African catfish (Clarias gariepinus) production. The system, covering 58.63 m², was established at the CSIR-Crops Research Institute in Ghana. It featured two treatment beds filled with locally-sourced river gravel substrate and was strategically planted with indigenous African species, including Taro (Colocasia esculenta) and sugarcane (Saccharum officinarum L.), selected for their proven phytoremediation capabilities and adaptation to tropical conditions.
The research systematically investigated the interactive effects of hydraulic retention time (1-3 days) and flow rate variations (54-108 L/min) on treatment efficiency. Results demonstrated significant improvements in key water quality parameters. The system effectively increased dissolved oxygen levels to 5.52 mg/L and maintained electrical conductivity (491-677 µS/cm), salinity (0.23-0.32 ppt), and total dissolved solids within acceptable ranges for aquaculture reuse. The system also achieved significant reductions in Total Suspended Solids (TSS) and Biological Oxygen Demand (BOD) (71% and 67% respectively), demonstrating its efficacy in pollutant removal and its potential for nutrient recovery.