Demulsifier Performance Study: Relationship between Demulsifier Properties with Crude Characteristics

Abstract

Due to the vast range of different types of crude oil characteristics which differ from region to region, wells and even day to day, developing and selecting effective demulsifiers for regional crude oils has been a time-consuming and tedious process. This experimental study defined a relationship between the crude characteristics of wax, asphaltene and crude API with relative solubility number (RSN) properties and chemistry groups of demulsifiers with their performances accordingly. Twenty-five different types of demulsifiers with RSN ranging from ten to twenty-three were tested using demulsifier bottle test. The demulsifiers comprise resin alkoxylate, modified polyol and polyimine derivative. Synthetic crude is used throughout the study with API of 27, 34 and 40. The wax and asphaltene contents of each crude API are varied. Based on the three chemistry groups, resin alkoxylate showed the best performance, while polyimine derivative-based demulsifiers had the poorest performance. The demulsifier with high RSN from 19 to 23 works best in resolving the emulsion compared to the low RSN demulsifiers. These findings provide valuable insights for the petroleum industry, offering guidance on demulsifier selection based on crude characteristics to optimize production, reduce operational costs, and effectively address emulsion-related challenges.