Review of the Current Laboratory Methods To Select Asphaltene Inhibitors

Abstract

Asphaltene deposition is a long-standing problem that threatens the uninterrupted production of crude oil. Unlike other flow assurance problems, downhole asphaltene deposition is not well-understood partly as a result of the complexity and diversity of the asphaltene chemical structure. Continuous downhole asphaltene inhibitor injection is one of the preventive strategies used to mitigate the asphaltene deposition problem. Such chemicals that are injected in low dosage are screened in the laboratory before field implementation. Over the last 20 years, various asphaltene testing methods have been proposed for product selection and research and development. Still, the lack of lab to field correlation remains a challenge for the operators, service providers, and chemical companies. Therefore, the search for robust, rapid, and reproducible lab screening methods for asphaltene inhibitors is ongoing. This review summarizes lab evaluation techniques adopted by different researchers, their governing principles, and the pros and cons. It may serve as a guide for adopting appropriate strategies and pursuing further investigations on the lessons learned. The hope is that, with a more in-depth understanding of the current methodologies, a better workflow can be designed to select the proper asphaltene control products for field implementation.