Effectiveness of vertical system planted with Renealmia Alpinia used in sub-humid climate to treat urban wastewater: a case study in the pilot site Bouregreg-ONEE RABAT

Abstract

Wastewater treatment is a global environmental issue. In Morocco, 45% of wastewater is treated before its discharge. Their impact on the environment is further aggravated by the degradation or absence of the sewerage liquid system. The constructed wetlands are alternative systems for the treatment of wastewater. Therefore, the aim of this study was to evaluate period adaptation (60 days) of a substitute plant Renealmia alpinia, and its potential for treating wastewater generated by the campus of the National Office of Electricity and Drinking Water (ONEE) of Rabat. A pilot experimental setup (tank) was constructed. The pumping rate was adjusted to 0.7 m3 / h while the density of R. alpinia planting on the surface of the filter massif was 6 plants/m2. At the end of monitoring, planting density was superior of 30, and R.alpinia plants have completed this phase clearly without any disease symptoms present. The treated water obtained from outlet and wastewater were analysed for various water quality parameters such as Biological oxygen demand (BOD), Chemical oxygen demand (COD) and Suspended solids (SS). The vertical system is able to remove 49 % of BOD, 80 % of COD, 88 % of SS. The results obtained are within the permissible limits for domestic rejects according to National legislation of Morocco. Overall results demonstrated that the selected plant posses a high potential for treating wastewater, it could represent a sustainable and inexpensive biotechnological strategy for untreated wastewater.