TY - JOUR
T1 - Comparison of fractal dimensions from nitrogen adsorption data in shale
T2 - via different models
AU - Liu, Kouqi
AU - Ostadhassan, Mehdi
AU - Jang, Ho Won
AU - Zakharova, Natalia V.
AU - Shokouhimehr, Mohammadreza
N1 - Funding Information:
The authors appreciate ND Core Library, Jeff Bader – the director and state geologist – as well as Kent Holland – library technician – for providing us with the samples. This research was supported by the National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT (2020M2D8A206983011). Furthermore, the nancial supports of the Basic Science Research Program (2017R1A2B3009135) through the National 18 Research Foundation of Korea is appreciated.
Publisher Copyright:
© 2021 The Royal Society of Chemistry.
PY - 2021/1/8
Y1 - 2021/1/8
N2 - The roughness of pore surfaces in shale reservoirs can affect the fluid flow, which makes it necessary to be characterized. Fractal dimension, a key component in fractal geometry, can be used to describe the surface irregularities. In this paper, we evaluated and compared the fractal dimensions of several shale samples with three major fractal models based on nitrogen adsorption isotherms. The results showed that Frenkel-Halsey-Hill (FHH), Neimark, and Wang-Li models all can be applied for fractal dimension characterization of shale samples. From theoretical thermodynamics, these three models should be considered identical based on the FHH equation. However, the experimental data obtained from these samples showed that the fractal dimensions that are derived from the Neimark model and Wang-Li model are the same while a discrepancy was observed with the results from the FHH model. The difference in the fractal dimensions in the experimental data among these three models was attributed to the micropore structures. It was found that as the micropore surface area or the micropore volume increases in the samples, the difference in the fractal dimensions would increase as well. If the number of micropores present in the samples is limited, all three models can become suitable for fractal dimension calculation in shale samples, otherwise, the Neimark or Wang-Li model is preferred. This journal is
AB - The roughness of pore surfaces in shale reservoirs can affect the fluid flow, which makes it necessary to be characterized. Fractal dimension, a key component in fractal geometry, can be used to describe the surface irregularities. In this paper, we evaluated and compared the fractal dimensions of several shale samples with three major fractal models based on nitrogen adsorption isotherms. The results showed that Frenkel-Halsey-Hill (FHH), Neimark, and Wang-Li models all can be applied for fractal dimension characterization of shale samples. From theoretical thermodynamics, these three models should be considered identical based on the FHH equation. However, the experimental data obtained from these samples showed that the fractal dimensions that are derived from the Neimark model and Wang-Li model are the same while a discrepancy was observed with the results from the FHH model. The difference in the fractal dimensions in the experimental data among these three models was attributed to the micropore structures. It was found that as the micropore surface area or the micropore volume increases in the samples, the difference in the fractal dimensions would increase as well. If the number of micropores present in the samples is limited, all three models can become suitable for fractal dimension calculation in shale samples, otherwise, the Neimark or Wang-Li model is preferred. This journal is
UR - http://www.scopus.com/inward/record.url?scp=85099757889&partnerID=8YFLogxK
U2 - 10.1039/d0ra09052b
DO - 10.1039/d0ra09052b
M3 - Article
AN - SCOPUS:85099757889
VL - 11
SP - 2298
EP - 2306
JO - RSC Advances
JF - RSC Advances
SN - 2046-2069
IS - 4
ER -