(6ju) Thermodynamic Behavior and Thermophysical Properties of Unusual Fluids: Heavy Oils

My research interest focuses on the prediction of fluid phase behavior and fluid properties for process design and simulation applications. Accurate properties are essential for cost-effective design, simulation, optimization and operation of industrial processes. For instance, transport properties are required for sizing of equipment and defining power requirements; and, thermodynamics properties, including phase equilibria, determine the feasibility of a given process. The goal of this poster is to present a glimpse of my research approach and relevant results from my doctoral, postdoctoral and industrial work.

To date, the subject of my research has been heavy oils and their mixtures with solvents. Modeling heavy oil properties and phase behaviour is challenging as these fluids consist of a wide variety of components ranging from light alkanes to the heaviest and most aromatic components found in nature. In this variety, both chemical family and molecular size are responsible for heavy oil high viscosity (as high as 1x10⁶ cP at room conditions) and its complex phase behaviour; especially partition into multiple phases (even solid phases) upon dilution. The research challenge addressed in my Ph.D. dissertation was to understand the governing physics to construct predictive models for the viscosity and thermal conductivity of heavy oils. Several experimental techniques for the measurement of viscosity and thermal conductivity of heavy oils at high temperatures and pressures (up to 200°C and 10 MPa, respectively) were proposed, developed, and validated; and, the formulated models encompass the whole phase diagram, including the critical and supercritical regions.

My postdoctoral research is aimed at interpreting and modeling the phase behaviour of diluted heavy oils. The main challenge of this project is predicting the formation of a “solid-like” phase rich in asphaltenes. Asphaltenes are a group of heavier, highly aromatic and polar components that self-associate and are insoluble in paraffinic solvents. Cubic Equations of State are not suitable for for asphaltene precipitation. SAFT Equations of State can be used to model asphaltene precipitation but require extensive tuning. I developed a Regular Solution based model that successfully predicts not only the conditions at which the asphaltene rich phase appears but also the mass of material that partition to this phase. Compared to equations of state, the proposed model is simpler, faster and predictive. I currently hold an industrial postdoctoral fellowship position at CNOOC Petroleum. My research is focused on understanding how changes of oil composition induced by thermal cracking affect its thermodynamic behavior. Additionally, I am implementing my Regular Solution based approach on one of the company’s process models. This postdoctoral fellowship has been awarded by MITACS and CNOOC Petroleum North America.

Future Research Plans:

Building on my expertise on data collection, modelling and computational aspects of phase equilibria calculations, I plan to extend my research to the formulation of models for electrolytes. Electrolytes have multiple applications in chemistry, geology, biochemistry, and chemical engineering. Understanding electrolyte thermodynamics is very important in the development of industrial processes such as carbon capture and utilization, removal of carbon dioxide from flue gases, desalination of water, bioprocesses, and pharmaceuticals. However, accurate data and phase behaviour/property models are scarce. This is the gap that my future research program will address.

Teaching Interests:

My teaching experience comes from three years as a teaching assistance (TA) and one term as a course instructor at the University of Calgary (Canada). As a TA, I was responsible for conducting laboratory demonstrations such as heat transfer, process control, mass transfer and fluid dynamics. As an instructor of the graduate level course Phase Behaviour of Reservoir Fluids, I oversaw the design of the course including the outline, assignments, supporting material, exercises, and exams. My teaching interests would focus thermodynamics, transport phenomena (momentum, mass and heat transfer), numerical methods, fluid dynamics and petroleum chemistry. Additionally, I am eager to design and teach a course focused on the application and computational aspects of thermodynamic models (including equations of state) for industrial process calculations.

Selected Publications:

Ramos-Pallares, F.; Schoeggl, F.F.; Taylor, S.D.; Yarranton, H.W. "Prediction of Thermal Conductivity for Characterized Oils and Their Fractions Using an Expanded Fluid Based Model”, Fuel, 2018, 234, 66-80.

Ramos-Pallares, F.; Schoeggl, F.F.; Taylor, S.D.; Yarranton, H.W. “Expanded Fluid- Based Thermal Conductivity Model for Hydrocarbons and Crude Oils”, Fuel, 2018, 224, 68-64.

Ramos-Pallares, F.; Lin, H.; Yarranton, H. W.; Taylor, S.D. “Prediction of the Liquid Viscosity of Characterized Crude Oils Using the Generalized Walther Model”, SPE Journal, 2017, 22, 1487-1505.

Ramos-Pallares, F.; Taylor, S.D.; Satyro, M.A.; Marriott, R.A.; Yarranton, H.W. “Prediction of Viscosity of Characterized Oils and Their Fractions Using the Expanded Fluid Model”, Energy and Fuels, 2016, 30, 7134-7157.

Ramos-Pallares, F.; Schoeggl, F.F.; Taylor, S.D.; Satyro, M.A.; Yarranton, H.W. “Predicting the Viscosity of Hydrocarbon Mixtures and Diluted Heavy Oils Using the Expanded Fluid Model”, Energy and Fuels, 2016, 30, 3575-3595.

Ramos-Pallares, F.; Lin, H.; Taylor, S.D.; Satyro, M.A.; Yarranton, H.W. “Predicting the Viscosity of Characterized Crude Oils”, Proc. 16th American Institute of Chemical Engineers Annual Meeting, San Francisco, CA, 2016.