The development and field application of new surfactant chemistries for application to heavy oils

Abstract

A critical part of any Oilfield production processing is oil and water separation and although this area has had highly efficacious demulsifier products developed for a number of production scenarios the application to "heavy" oils remains problematic. Over 70% of the future recoverable reserves have been designated as heavy oil and these developments will pose a number of unique oil and water separation challenges in production, transportation and refining compared to lighter crudes. Demulsification and desalting of these challenging crudes is needed in a wide variety of secondary and tertiary enhanced oil recovery applications and techniques, including waterflooding, steam assisted gravity drainage and cyclic steam stimulation. This paper describes the laboratory development and subsequent field-testing of a specific range of chemistry for application to broad spectrum of heavy oil scenarios. It was found that specific properties related to interfacial tension were important, and this will be elaborated further. From the data, a model situation using specifically selected heavy oils has been developed for the evaluation of a number of surfactant chemistries, the criteria also includes a structure versus performance relationship to identify optimum surfactant properties. This work has resulted in a tailored range of demulsifiers, which will add to the relatively small number of chemistries able to effectively be applied across the growing heavy oil development and production area. In addition to technical efficacy recognition of environmental impact and some specific chemistry relating to application in environmental regulated areas such as the North Sea will be discussed. Copyright 2013, Society of Petroleum Engineers.