Molecular Dynamics Simulation of Asphaltene Deposition During CO_2 Miscible Flooding

摘要

We use molecular dynamics (MD) to calculate the interaction of aggregates with different solvents at 370 K to simulate the course of CO2 injection and present a review of what prerequisites can influence the asphaltene deposition. The solvents are pure CO_2; a mixture of methane and ethane; a mixture of methane, ethane, and octane; and a mixture of octane and CO_2. The results show that pure CO_2 would enhance the hydrogen bond and the dipolar interaction in asphaltene aggregates. The pi-pi charge-transfer interaction will be greatly enhanced after CO_2 injection at 370 K. This indicates that the more aromatic clusters and heteroatoms the asphaltenes have, the greater the deposition of asphaltene will be after CO_2 injection.