Multicomponent Shale Oil Flow in Real Kerogen Structures via Molecular Dynamic Simulation

Jie Liu,Yi Zhao,Qingyan Mei,Yongfei Yang,Shan Yang,Chenchen Wang

doi:10.3390/en13153815

Abstract

As an unconventional energy source, the development of shale oil plays a positive role in global energy, while shale oil is widespread in organic nanopores. Kerogen is the main organic matter component in shale and affects the flow behaviour in nanoscale-confined spaces. In this work, a molecular dynamic simulation was conducted to study the transport behaviour of shale oil within kerogen nanoslits. The segment fitting method was used to characterise the velocity and flow rate. The heterogeneous density distributions of shale oil and its different components were assessed, and the effects of different driving forces and temperatures on its flow behaviours were examined. Due to the scattering effect of the kerogen wall on high-speed fluid, the heavy components (asphaltene) increased in bulk phase regions, and the light components, such as methane, were concentrated in boundary layers. As the driving force increased, the velocity profile demonstrated plug flow in the bulk regions and a half-parabolic distribution in the boundary layers. Increasing the driving force facilitated the desorption of asphaltene on kerogen walls, but increasing the temperature had a negative impact on the flow velocity.

Highlights

The development of shale oil has ameliorated global energy shortages, and many countries have launched programmes to investigate various development approaches [1,2,3]
We examined examined the the effects effectsofofthe the (NEMD)simulation simulationtotoanalyse analysethe theflow flow behaviour behaviour of of shale shale oil
The free slit layer (FSL) was defined as the free space without kerogen, and the rough adsorption layer (RAL) was comprised of the cavities

Summary

Introduction

The development of shale oil has ameliorated global energy shortages, and many countries have launched programmes to investigate various development approaches [1,2,3]. The complex structure of nanopores in shale and the different components in shale oil hinder the further study of shale oil flow behaviours [4,5]. Molecular dynamic (MD) simulations are often used to study the fluid behaviours within nano-confined spaces [13]. Shale is mainly composed of organic and inorganic matter [14,15,16]. The inorganic matter contains quartz and clay minerals. As a source of oil, kerogen is the main component of organic matter [17]. The flow behaviour of shale oil in realistic kerogen channels needs to be investigated

Methods

Results

Conclusion