Performance of Hybrid Constructed Wetland System for the Treatment of Secondary Wastewater Effluent under Arid Climate Conditions (Southeastern Algeria): A Laboratory Scale Investigation

Document Type : Original Research Paper

Authors

1 Laboratory of Water and Environmental Engineering in the Saharan Region, Faculty of applied sciences, Department of civil and hydraulic engineering, University of Kasdi Merbah Ouargla, PO Box 511, Ouargla, 30000, Algeria

2 Laboratory of Water and Environmental Engineering in the Saharan Region, Ecole Normale Supérieure, University of Kasdi Merbah Ouargla, PO Box 511, 30000, Ouargla, Algeria

3 Research Laboratory in Subterranean and Surface Hydraulics, University of Biskra, 07000, Biskra, PO Box 145 RP, Biskra, 07000, Algeria

4 Hydraulic and Civil Engineering Department, University of El Oued, PO Box 789, El Oued, 39000, Algeria

5 Laboratoire de Protection des Ecosystèmes en zones Arides et Semi-Arides, Department of Technical Sciences, University of Kasdi Merbah Ouargla, PO Box 511, Ouargla, 30000, Algeria

6 Laboratory of Water and Environmental Engineering in the Saharan Region, University of Kasdi Merbah Ouargla, PO Box 511, Ouargla, 30000, Algeria

7 University of Amine Elokkal El Hadj Moussa Eg Akhamouk Tamanghasset, 11000 Tamanrasset

8 Laboratory of Water and Environment, Bioresource, Physical-Geochemistry, Legislation and Development Socio-Economic, University of Tamanghasset, Algeria

9 University of El Oued, PO Box 789, El Oued, 39000, Algeria

10.22059/poll.2022.349117.1637

Abstract

Constructed wetland (CWs) systems offer an economical alternative to wastewater (WW) treatment in developing countries. So this study investigated lab-scale hybrid constructed wetlands (HCWs) with plant species Canna indica and Typha latifolia in mono and mixed culture for removing organic matter and nutrients from municipal wastewater (MWW) under arid climatic conditions. A HCW system consists of a storage tank feeding four series of vertical flow constructed wetlands (VFCWs) followed by horizontal flow-constructed wetlands (HFCWs). The results indicate that the planted beds performed better in removing suspended solids (TSS) (89.93% by Typha latifolia), biochemical oxygen demand (BOD5) (95.01% by mixed-culture), chemical oxygen demand (COD) (90.77 by Typha latifolia), nitrite (NO2-) (89.99% by mixed-culture), ammonium nitrogen (NH4+) (99.98 % by mixed-culture), and orthophosphate (PO43-) (87.22% by Typha latifolia) as compared to the unplanted bed for the same parameters (87.85%, 92.87%, 77.35%, 85.30%, 99.75%,  and 80.95%), respectively. The nitrate (NO3−) concentration in the effluent recorded the highest increase in the VFCW unit planted with mixed culture from 0.44 to 0.999 mg/l and decreased in the second stage to 0.588 mg/l at the HCW outlet. The mean values of the testing parameters in different HCW systems were not significant between the mono and mixed culture (P > 0.05), with a significant difference (P <0.05) between the VFCWs and HFCWs. The finding of this study demonstrated that Canna indica and Typha latifolia have been effective in WW treatment by HCW systems.

Keywords


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