Electrocoagulation with aluminum electrodes was used to treat the vegetable oil refinery wastewater (VORW) in a batch reactor. The effects of operating parameters such as pH, Current density, PAC (poly aluminum chloride) dosage and Na2SO4 dosage on the removal of organics and COD removal efficiency have been investigated. It has been shown that the removal efficiency of COD increased with the increasing applied current density and increasing PAC and Na2SO4 dosage and the most effective removal capacity was achieved at the pH 7. The results indicate that electrocoagulation is very efficient and able to achieve 98.9% COD removal in 90 min at 35 mA cm(-2) with a specific electrical energy consumption of 42 kWh (kg CODremoved)(-1). The effluent was very clear and its quality exceeded the direct discharge standard. (C) 2007 Elsevier Ltd. All rights reserved.