[01] Masood Abdusalam Ghanem Ali, Department of Geology and Environment, Faculty of Sciences, Baniwaleed University, Baniwaleed City, Libya. [02] Amer Gheit, Department of Geology and Environment, Faculty of Sciences, Baniwaleed University, Baniwaleed City, Libya. [03] Salim Shouran, Department of Geology and Environment, Faculty of Sciences, Baniwaleed University, Baniwaleed City, Libya.

The research assessed the potential of up flow anaerobic sludge blanket (UASB) reactors to provide full-flow anaerobic treatment of wastewater 35°C. The work was carried out using laboratory-scale UASB reactors fed on a wastewater. The reactors were operated under a range of condition to test their performance and stability based on four main indicators: chemical oxygen demand (COD) removal, total suspended solids (TSS) removal, gas production and gas composition. The results from this investigation showed that UASB reactors operated at a temperature of 35°C were highly effective in the treatment of synthetic sewage at influent COD concentrations from 450 to 2250 mg l^-1 COD at a constant HRT of 1 day, and at HRT from 24 to 8 hours with an influent COD concentration of 450 mg l^-1. The specific methane yield obtained was around 0.32 l CH₄ g^-1 COD removed. COD removal efficiencies were high at ≥ 93% and total suspended solid removal was around 95%. The results confirmed that full flow treatment under mesophilic conditions, was feasible at wastewater temperatures of 35°C. The warm temperate areas that are suited to this application, e.g. Libya also often have relatively low water use and/or high rates of re-use due to water scarcity.

(UASB) Reactors, COD Removal, TSS Removal, Methane, Mesophilic Conditions

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