Chemical Demulsifier Development Based on Critical Electric Field Measurements

Abstract

Abstract Resolution of water and oil emulsions is critical to the oil field industry. A wide variety of undesirable emulsions are formed during the production, handling and processing of crude oil. Although various methods are used, dehydration of crude oils is mostly achieved by gravitational sedimentation, normally at elevated temperatures and with the addition of chemical demulsifiers. The quantitative evaluation of emulsion stability by a Critical Electric Field (CEF) technique was developed to play a significant role in chemical demulsifier research. It was found that the CEF technique is not only useful in the evaluation of water-in-oil emulsion stability, but also in studying the mechanisms of stabilization as well as demulsification. A method was developed to study the mechanism of emulsion stabilization in terms of flocculation and coalescence behavior of a crude oil emulsion. The effect of chemical demulsifiers on emulsion stability was evaluated in terms of the method developed in this study. By following this approach, it is possible to determine the relative amount of energy required for both flocculation as well as coalescence, in the presence of a chemical demulsifier.