Bahadori - National Iranian South Oil Company, Ahvaz
Ayatollahi - University of Shiraz
Moshfeghian - University of Shiraz

An intermediate pressure, called optimum separator pressure, was selected to maximize the oil volume accumulation in the stock – tank, in Pazanan production unit. This production unit produces 36000 bbl/day and it is located in southwestern Iran. Stage separation is a process in which gaseous and liquid hydrocarbons are flashed (separated) into vapor and liquid phases by two or more separators. The purpose of the stage separation then is to reduce the pressure on the produced oil in steps so that more stock–tank oil recovery will result. If the separator pressure is high, large amounts of light components will remain in the liquid phase at the separator and will be lost along with other valuable components to the gas phase at the stock–tank. On the other hand if the pressure is too low, large amounts of light components will be separated from the liquid and they will attract substantial quantities of intermediates and heavier components so it is necessary to optimize separators pressure in winter and summer situation. Considerable gains could be realized by implementing of recommendations.

production unit, optimization, oil recovery