Crude oil usually contains amounts of water and salt compounds.The presence of salt in crude oil causes many problems in the oil refining process, such as corrosion, fouling, poisoning of the catalysts and plugging. So salt compounds must be removed from crude oil in refinery units. In this study, the treatment methodology of crude oil desalting was investigated by applying the analytic hierarchy process (AHP). For choosing a prioritizing treatment and practical method of crude oil desalting Expert Choice software was applied to simplify decision. There are many processes for desalting such as Thermal, Gravity and Electrical methods. The modified Electrostatic, Reverse Osmosis and Hydro cyclone process were selected as alternative options and cost, efficiency, time of reaction and scale-up were chosen as criteria. The obtained results were illustrated which cost option ranked first among criteria at 43.9% and modified Electrostatic was selected as the proposed method with 48.3% of priority.
