Study On The Optimization Deep Desalting Technology Of Crude Oil

In recent years, with the increasing of crude oil demand and heavier, inferior trend, it made the device desalting efficiency droping and operation unstable, the reaching standard rates of salt and water were significantly reduced, and the process can’t meet the requirements of the qualified rate more than90%, which effected the follow-up crude processing, and increased the energy consumption. Therefore, the electric desalting device reaching the standard has became one of the difficulties and hotspots for domestic and foreign refineries,which need to be resolved.In order to seek an economic effectively method to solve the problem of salt and water content below standard after the deep desalting, the paper based on the current technology of the crude oil electric desalting, first of all, the demulsifiers of electric desalting process were researched and evaluated in the laboratory, it was found that demulsifier E-H was the best one, then the demulsifier E-H was used in the industrial scale-up. When the electric desalting temperature was130℃, the salt content of two levels desalting were up to the standard, the oil content of drainage was qualified. Second, the electric desalting device was transformed, the AC/DC transformer was transformed into pulse transformer. It was found that the salt content of two levels desalting and the oil content of drainage were up to the standard when the output power was200KVA, and the energy consumption reduced obviously,so the pulse transformer was better than AC/DC transformer. Third, the decalcifying agent MTPR was used in the electric desalting technology, the results showed that the decalcifying effect of MTPR was good and did not impact the drainage water quality significantly. Finally, through the optimization of the electric desalting technology, the best technology parameters were concluded:one level desalting temperature and two level desalting temperature were135℃and130℃, the dosage of E-H demulsifier was10mg/1, the injection quantity of water was3%, one level desalting and two level desalting mixed strength were0.06MPa and0.05MPa, the electric field intensity was1000v/cm, the stayying time was2minutes.Through the optimization of technological process for electric desalting and the transformation of the electric desalting device, the electric desalting effect of current device was improved ultimately. The salt content of two levels desalting was less than3mg/1, the water content was less than0.3%, and the oil content of drainage was less than150mg/l, which made the electric desalting device realize the long-term operation and provide high quality materials for subsequent processing device.