Continuous Realtime Asphaltene Monitoring and Surveillance in Gulf of Mexico Deepwater Production

Abstract Asphaltenes are compounds within crude oil that are both polar and paramagnetic and that have a strong tendency to self-aggregate, leading to flocculation and fouling. Their precipitation and deposition present significant challenges in offshore production, particularly in the Gulf of Mexico (GOM). While chemical treatment programs are commonly employed to mitigate these effects, the difficulty of assessing real-time effectiveness can hinder treatment optimization. This paper presents the results of the first-ever offshore deployment of a novel asphaltene measurement sensor that can help chemical program optimization and improve real-time surveillance capability. The sensor quantifies asphaltene content in real time by detecting its paramagnetic signature, offering a continuous surveillance method that can enhance chemical management strategies. Laboratory validation of that quantification for GOM oils confirmed a consistent correlation between asphaltene content and paramagnetic signature, aligning with similar findings from Middle Eastern crudes. These results provided confidence in the sensor's ability to provide actionable data offshore. The 18-month offshore trial required a collaborative effort between the operator and the sensor provider, addressing challenges such as data integration, sensor calibration and ease of maintenance. Deployment was complicated by the commingling of production from multiple subsea wells into two risers, with the sensor initially installed on only one riser. To overcome these issues, it was possible to integrate real-time asphaltene data with traditional operational parameters such as well alignments and made accessible through both vendor and operator real-time production dashboards. The sensor proved effective in monitoring baseline asphaltene levels subject to changes in subsea configuration, quantifying solvent soak returns, monitoring for changes in asphaltene levels due to changes in chemical treatments and observing relative differences in surface asphaltene content due to compositional variations from zonal production. In addition, the observed similarities in asphaltene behavior across GOM and Middle Eastern crudes suggest universal patterns in deposition processes, despite regional differences in crude properties. This study thereby demonstrates the value of real-time asphaltene surveillance in reducing fouling risks and optimizing offshore production, offering a promising pathway for more efficient and effective chemical management programs.