Related Experiment Video
Updated: Jan 6, 2026
Mesocosm-Scale Constructed Wetland Design for Wastewater Treatment
Published on: May 2, 2025
Effect of organic loading rates on olive pomace biochar-enhanced vertical flow constructed wetlands for wastewater
Sofiane El Barkaoui1,2, Naaila Ouazzani1,3, Houria Ryah1,3
1Laboratory of Water Sciences, Microbial Biotechnologies and Natural Resources Sustainability, Faculty of Sciences Semlalia, Cadi Ayyad University, 40000, Marrakech, Morocco.
Abstract:
This study investigates the performance of vertical flow constructed wetlands (VF-CWs) using olive pomace biochar (CW-B) versus a sand-only control (CW-C) under two organic loading rates (OLR): low (20 g COD/m2.d) and high (70 g COD/m2.d). At low OLR, CW-B achieved higher removal efficiencies than CW-C, with 60% vs. 50% for COD, 85% vs. 71% for NH₄⁺-N, 74% vs. 52% for TKN, 81% vs. 67% for TSS, and over 3-log unit reductions in faecal indicators. Increasing OLR led to an overall decrease in treatment efficiency, although CW-B remained superior. Biochar had a limited effect on phosphorus, sulphate, and hardness removal. Release of NO₂ and NO₃ confirmed active nitrification, which decreased at high OLR. These results highlight the potential of olive pomace biochar as a sustainable and effective VF-CW substrate, especially under moderate organic loads.
