Investigation of treatment potential of vertical Gravel &amp; sponge Bed Hydroponic Planted with Durant Erecta for Domestic wastewater
Creators: name: Gebreabe, Solomon Tibebu
Publisher: name: National Academic Digital Repository of Ethiopia
Year: 2020
Subjects: Domestic wastewater, Duranta Erecta, Kilinto Federal Prison Camp

description: Wastewater generated from domestic sources including institutions such as Prison Camp<br> pollutes the environment in general and water bodies in particular. The direct discharge<br> of untreated domestic wastewater from Kilinto Federal Prison Camp causes environmental<br> problems and health risks in the surrounding area including Akaki Fanta River and the<br> downstream communities along the river. The objective of this study is to investigate the<br> treatment potential of vertical (gradual) gravel and Sponge bed hydroponic planted with<br> Duranta Erecta for domestic wastewater generated from Kilinto Federal Prison Camp.<br> Experimental set up of Pilot-scale non-circulating vertical gravel and sponge bed<br> hydroponics planted with Duranta Erecta with their corresponding control units was used<br> for the investigation. Each experimental and control unit contains three reactors.<br> Experimental unit one uses gravel as a media and experimental unit two uses polyester<br> sponge as a media. Five plants per each reactor were planted in both experimental units.<br> There are no plants in both control units. Control unit one only have gravel as a media,<br> but control unit two does not have any media. Onsight sample analysis and composite<br> sampling was used to collect samples from the direct discharge point of untreated Kilinto<br> Prison camp effluent. The wastewater was first characterized by taking a sample for four<br> consecutive months then; it was transported to the experimental site and treated by the<br> pilot-scale hydroponic wastewater treatment plant. Hydraulic retention time of one, three,<br> five and seven days were applied for treating the given wastewater. Grap sampling was<br> used to characterize the influent and treated effluent. Different physicochemical and<br> bacteriological parameters were used to characterize untreated and treated wastewater.<br> Plant growth parameters such as plant morphology and nutrient accumulation was used<br> to study the plants. Pollutants in the influents were reduced significantly (p&lt;0.05) than<br> that of effluents in all experimental and control units. Among the applied four HRT’s<br> maximum removal efficiency for all experimental and control units was obtained at HRT<br> of 7 days (HLR of 4.389*10-7m/Sec). The maximum removal efficiency of experimental<br> units one and two at optimum HRT and HLR in removing solids was 96.45% and 89.31%<br> for TSS, 49.15%, and 32.9% for TDS and 94.32% and 87.24% for turbidity respectively.<br> The maximum removal efficiency of experimental units one and two at optimum HRT in<br> removing organic matter was 94.57% and 89.78% for BOD5, 95.44%, and 90.65% for<br> COD respectively. The maximum removal efficiency of experimental unit one and two at<br> optimum HRT in removing nutrient was 52% and 42.65% for NH3+,99.19% and 47.17%<br> for NO2-, 82.67% and 73.67% for NO3- 54.6% and 43.69% for TN, 51.33% and 42.83%<br> for PO43-, 32.11% and 25.7% for TP respectively. The maximum removal efficiency of<br> experimental units one and two at optimum HRT in removing bacteria was 98.7% and<br> 89.8% for heterotrophic bacteria, 96.21%, and 86.75% for total coliform and 92.9% and<br> 84.01% for fecal coliform respectively. An increment in plant growth parameters. was<br> observed in both experimental units at the end period of the experiment (treatment). Both<br> vertical gravel and sponge bed hydroponics can remove physicochemical and bacteriological<br> pollutants from the prison camp effluent in an effective and environmentally friendly way.<br> Because of its high treatment capacity, its high-cost effectiveness, its ability to increase the<br> aesthetics of the environment, its positive role in decreasing global warming, and many other<br> benefits, scaling up the pilot scales of both Non-circulating vertical gravel and sponge bed<br> hydroponics will have a great advantage in Ethiopia and other developing countries.