Analysis of imbibition of n-alkanes in kerogen slits by molecular dynamics simulation for characterization of shale oil rocks  

作　　者：Qian Sang Xin-Yi Zhao Hui-Min Liu Ming-Zhe Dong 

机构地区：[1]Key Laboratory of Unconventional Oil&Gas Development(China University of Petroleum(East China)),Ministry of Education,Qingdao,266580,Shandong,China [2]School of Petroleum Engineering,China University of Petroleum(East China),Qingdao,266580,Shandong,China [3]Management Center of Oil&Gas Exploration of Shengli Oilfield Branch Company,SINOPEC,Dongying,257001,Shandong,China [4]Department of Chemical and Petroleum Engineering,University of Calgary,Calgary,AB,Canada,T2N 1N4

出　　处：《Petroleum Science》2022年第3期1236-1249,共14页石油科学（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(Grant No.52004317,42090024);the Natural Science Foundation of Shandong Province of China(No.ZR2020ME091);the Fundamental Research Funds for the Central Universities(20CX06016A);the National Science and Technology Major Project(2017ZX05049-004)

摘　　要：Shale oil formations contain both inorganic and organic media.The organic matter holds both free oil in the pores and dissolved oil within the kerogen molecules.The free oil flow in organic pores and the dissolved oil diffusion in kerogen molecules are coupled together.The molecular flow of free n-alkanes is an important process of shale oil accumulation and production.To study the dynamics of imbibition process of n-alkane molecules into kerogen slits,molecular dynamics(MD)simulations are conducted.Effects of slit width,temperature,and n-alkane types on the penetration speed,dynamic contact angle,and molecular conformations were analyzed.Results showed that molecular transportation of n-alkanes is dominated by molecular structure and molecular motion at this scale.The space-confinement conformational changes of molecules slow down the filling speeds in the narrow slits.The n-alkane molecules with long carbon chains require more time to undergo conformational changes.The high content of short-chain alkanes and high temperature facilitate the flow of alkane mixtures in kerogen slits.Results obtained from this study are useful for understanding the underlying nanoscale flow mechanism in shale formations.

关 键 词：Molecular flow IMBIBITION N-ALKANE Kerogen slit Molecular dynamics simulation 

分 类 号：TE311[石油与天然气工程—油气田开发工程]