ABSTRACT Upflow anaerobic sludge blanket (UASB) reactor is very effective in treating POME because it has a sludge bed, sludge blanket, gas separator, fluid separator and higher methane production. The aims of this research were to study the effect of flow rate on total COD, dissolved COD, bacterial growth through VSS, total volatile acid formation (TAV), biogas production, sludge volume index…