Molecular Structure of Petroleum Interfaces in Relation to Environmental Stewardship and Efficient Production

Nanoscale, microscale, and ionic aggregation both in the bulk and interfaces are becoming increasingly viable in relation to efficient production of hydrocarbon resources as well the environmental stewardship. Use of small quantities of functional molecules has the potential to improve both efficiency and reduce environmental impact in hydrocarbon production. Salt concentration in the injected water may have a profound effect on improved oil recovery. The functional molecules in small quantities can reduce the need for harmful chemicals in flow assurance and safe production of natural gas considered by many as the transformational fuel. In relation to the effect of salt concentration, the understanding of the mechanisms despite some 500 papers on the subject is limited. Molecular structure at the fluid-fluid and fluid-solid interfaces would provide insight.

 

This presentation will cover a combination of MD simulations and basic concepts to compute aggregation of molecules and molecular structures. The structure of methane and propane hydrates are computed first; some 50 and 150 molecules are assembled to form the unit cells of methane and propane hydrates, respectively. In a more detailed demonstration, the contact angle in two petroleum fluid systems will be predicted as a function of NaCl concentration. Mica is the substrate. For the first time we demonstrate agreement from atomistic MD simulations of contact angle and lab measurements. We also show that the oil composition can result in non-monotonicity of contact angle with salt concentration in line with our recent measurements.