(74h) Microfluidic Systems That Mimic Reservoir Conditions for Visualizing Asphaltene Aggregation and Deposition Near Wellbore Conditions

Asphaltene deposition is well known as a cause of production rate decline and various other operational problems in most oil production processes. Asphaltenes are typically stable under virgin reservoir condition, however may be destabilized and precipitate from crude oil and deposit on the internal surface of equipment or near-wellbore reservoir during production and transportation. Asphaltenes precipitation and deposition are often due to changes in thermodynamic properties, and pressure has a large effect on the flocculation of asphaltenes. Previous studies have investigated these phenomena in bulk volume (e.g. in stainless steel pipe) but visualization are often missed in these “black-box” type experiments, and the results from such macroscopic observations could not reflect the nature of asphaltenes at micro-scale. Micro-scale behaviors of asphaltenes are important for the fundamental understanding of origins of asphaltene flow assurance problems. Prevention and mitigation of asphaltene problems may also need to be applied at the source of crude oil in wellbore conditions and in porous media. Hence there is a great need to fill in the gap by visualizing asphaltene aggregation and deposition behaviors at micro-scale near wellbore conditions. In this report, we will demonstrate preliminary results of such experiment using microfluidic systems. The variation of asphaltene solubility in model oil with change of pressure will be visualized in micromodel, and flow experiment of asphaltene deposition on porous media surface will also be demonstrated. These microfluidic experiments has the potential to provide new information for fundamental research at wellbore conditions as well as a mean of fast inhibitor development.