Phytoremediation potential of Duranta erecta in cascade hydroponics for effective domestic wastewater treatment

Abstract

Discharging untreated wastewater into natural water systems poses significant risks to public health, economies, and ecological stability worldwide. This study addresses these effects by investigating the phytoremediation potential of Duranta Erecta in cascade hydroponics for treating domestic wastewater. It centers on the removal of dissolved and suspended solids as well as organic matter, representing a groundbreaking effort in this domain. It involved two experimental setups: one integrating Duranta Erecta with media (gravel (EXU-1) and polyester sponge (EXU-2)), and a control setup ((gravel (COU-1) and polyester sponge (COU-2))) using only media. Each configuration consisted of three bioreactors designed to treat wastewater from Kilinto prison camp. Four hydraulic retention times (HRTs) were tested, with the 7-day HRT emerging as the most effective compared to the 1, 3, and 5-day intervals. At the 7-day HRT, experimental units one and two demonstrated substantial reductions in pollutants: suspended solids (96.50 % & 89.3 %), turbidity (94.3 % & 87.2 %), dissolved solids (49.5 % & 45.15 %), biological oxygen demand (94.57 % & 89.78 %), and chemical oxygen demand (95.44 % & 90.65 %). Statistical analysis confirmed these reductions as statistically significant (P < 0.05). These findings highlight Duranta Erecta cascade hydroponics as a promising decentralized wastewater treatment technology, particularly suitable for developing countries like Ethiopia.