Effect of Crude Oil Aging on Asphaltene Inhibitor Product Recommendation

Abstract

Aging refers to the deterioration of hydrocarbon fluids that manifests as changes in the physicochemical characteristics of the fluid upon exposure to ambient conditions. In order to understand the effect of aging of crude oils on asphaltene inhibitor product recommendation, simulated aging studies were performed on a crude oil from Wyoming with known asphaltene issues. The results clearly show that aging of crude oil affects the stability of the oil with respect to asphaltenes and caution must be exercised when recommending asphaltene inhibitor if the evaluations were performed on fluids after long-term storage. A real case study where ambient storage in the lab adversely affects the stability of the crude oil and renders asphaltene inhibitor ineffective further confirms results from simulated aging.

Keywords:

• Aging
• asphaltene stability
• fluid composition
• inhibitor recommendation
• optimization

Acknowledgments

The authors thank Prima Exploration for providing the crude oil employed in this study and Nalco Company for the permission to publish the results. FTIR and TAN analysis by Dr. Jeffrey R. Eveland and Mr. Robert A. Pultz is highly appreciated.