Molecular Simulation of Hydrocarbon Adsorption on Mineral Surfaces: Insights for Hydrocarbon Occurrence in Nano Pores
Keyu Liu1,2, Jungfang Zhang1, and Shuichang Zhang2
1CSIRO Earth Science and Resource Engineering, Bentley, WA, Australia
2Research Institute of Petroleum Exploration and Development, PetroChina, Beijing, China
Molecular simulation (MS) is a computer simulation of physical movements of interacting atoms and molecules in a complicated and complex system. The trajectories of atoms and molecules are determined by numerically solving the Newton’s equations of motion where forces between the atoms and molecules are defined by the fields of molecular mechanics force. Molecular systems consist of a vast number of particles. It is impossible to find the properties of such complex systems analytically. However, MS is able to circumvent such a problem by using numerical methods. MS has been shown to be useful in determining macroscopic thermodynamic properties, mechanical properties and transport properties for systems for which little or no experimental data are available. It effectively links between the microscopic and the macroscopic domains, and theory and experiments.
In the investigation of unconventional petroleum systems such as tight oil and shale gas reservoirs, the occurrence and phase behaviour of hydrocarbons in the nano pores remain enigmatic. There are quite a few hypotheses on how light hydrocarbons and gases are adsorbed on the reservoir matrix under reservoir P/T conditions. Some of the hypotheses cannot be verified in the laboratory due to the physical limitations (e.g. P/T) of the instruments. MS thus provide a valuable tool to evaluate the occurrence and phase behaviour of the hydrocarbons at nanoscales.
AAPG Datapages/Search and Discovery Article #90180©AAPG/SEPM/China University of Petroleum/PetroChina-RIPED Joint Research Conference, Beijing, China, September 23-28, 2013