Porosity controls and fractal disposition of organic-rich Permian shales using low-pressure adsorption techniques

Hazra, Bodhisatwa; Wood, David A.; Vishal, Vikram; Varma, Atul Kumar; Sakha, Dhruba; Singh, Ashok K.

doi:10.1016/j.fuel.2018.02.023

Cited by 140 publications

(88 citation statements)

References 73 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The differences of porosity, connectivity, and topology of pore space always determine the macroscopic seepage properties [10,11]. The pore space of the reservoir core can be obtained by multi-laboratory test methods [12][13][14][15]. The obtained pore space images and parameters can also lay the foundation for calculation of permeability [16][17][18].…”

Section: Introductionmentioning

confidence: 99%

Pore Structure Fractal Characterization and Permeability Simulation of Natural Gas Hydrate Reservoir Based on CT Images

et al. 2020

View full text Add to dashboard Cite

The gas-water two-phase seepage process is complex during the depressurization process of natural gas hydrate in a clayey silt reservoir in the South China Sea, the transport mechanism of which has not been clarified as it is affected by the pore structure. In this study, we select six clayey silt samples formed after the dissociation of natural gas hydrate in the South China Sea, employing CT scanning technology to observe the pore structure of clayey silt porous media directly. The original CT scanning images are further processed to get the binarized images of the samples, which can be used for simulation of the porosity and absolute permeability. Based on the fractal geometry theory, pore structures of the samples are quantitatively characterized from the aspect of pore distribution, heterogeneity, and anisotropy (represented by three main fractal geometric parameters: fractal dimension, lacunarity, and succolarity, respectively). As a comparison, the binarized CT images of two conventional sandstone cores are simulated with the same parameters. The results show that the correlation between porosity and permeability of the hydrate samples is poor, while there is a strong correlation among the succolarity and the permeability. Fractal dimension (represents complexity) of clayey silt samples is higher compared with conventional sandstone cores. Lacunarity explains the difference in permeability among samples from the perspective of pore throat diameter and connectivity. Succolarity indicates the extent to which the fluid in the pore is permeable, which can be used to characterize the anisotropy of pore structures. Therefore, these three fractal parameters clarify the relationship between the microstructure and macroscopic physical properties of clayey silt porous media.

show abstract

Section: Introductionmentioning

confidence: 99%

Pore Structure Fractal Characterization and Permeability Simulation of Natural Gas Hydrate Reservoir Based on CT Images

et al. 2020

View full text Add to dashboard Cite

show abstract

“…However, the CS2 and CS3 samples with steeper isotherm slopes at a higher relative pressure show larger pore volumes after high-temperature combustion. 49 Thus, the capacity of the CS2 and CS3 samples to store water molecules was improved.…”

Section: Results and Discussionmentioning

confidence: 99%

Experimental Study of the Wettability Characteristic of Thermally Treated Shale

Yang

Gu²,

Chen

et al. 2020

ACS Omega

View full text Add to dashboard Cite

Extraction of shale gas from shale reservoirs is significantly affected by shale wettability. Recently, thermal recovery technologies (e.g., combustion) have been tested for shale gas recovery. This requires an understanding of the wettability change mechanism for thermally treated shale samples. In this study, the effect of combustion on shale wettability was investigated. Shale samples were first processed to obtain smooth surfaces and then combusted at temperatures of 200, 400, and 800 °C. The initial contact angles and dynamic behavior of water droplets on shale surfaces were recorded using the sessile drop method. It was found that pores and fractures were generated on the shale surfaces following high-temperature combustion. The pore volume and diameter increased with increasing combustion temperature, which improved the connectivity of hydrophilic pore networks. Compared to a raw shale sample, the shale sample combusted at 400 °C showed a smaller initial water contact angle and a more rapid decrease in the contact angle because of the oxidation of organic matter and generation of pore structures. Water droplets were found to completely spread over the surface of the shale sample combusted at 800 °C because of the generation of fractures. Moreover, the van der Waals potential between water droplets and combusted shale samples was determined to be stronger. However, the initial contact angle and dynamic behavior of water droplets did not show a significant change for the shale sample combusted at 200 °C. As a result, high-temperature combustion (≥400 °C) can be used to significantly improve the hydrophilicity of shale.

show abstract

“…A value of D equal to 2 indicates a perfectly smooth surface, while a fractal dimension approaching 3 indicates a more heterogeneous pore structure or a completely irregular and rough surface 26,31 . The fractal dimension calculated from LPNA data has been demonstrated to be useful in characterizing pore structure heterogeneity 21,32,33 . Among several models, such as the Langmuir model, the thermodynamic model, and the BET model, which can be used to measure the fractal dimension of shale using LPNA data, the Frenkel‐Halsey‐Hill (FHH) model is considered as the most extensively applicable model for fractal dimension calculations and has been widely applied in porous materials.…”

Section: Samples and Methodsmentioning

confidence: 99%

“…26,31 The fractal dimension calculated from LPNA data has been demonstrated to be useful in characterizing pore structure heterogeneity. 21,32,33 Among several models, such as the Langmuir model, the thermodynamic model, and the BET model, which can be used to measure the fractal dimension of shale using LPNA data, the Frenkel-Halsey-Hill (FHH) model is considered as the most extensively applicable model for fractal dimension calculations and has been widely applied in porous materials. The FHH model can be described by the following equation:…”

Section: Fractal Dimensions From Lpnamentioning

confidence: 99%

Reservoir heterogeneity of the Longmaxi Formation and its significance for shale gas enrichment

Zhang

Liang

Pang

et al. 2020

Energy Science & Engineering

View full text Add to dashboard Cite

show abstract

Porosity controls and fractal disposition of organic-rich Permian shales using low-pressure adsorption techniques

Cited by 140 publications

References 73 publications

Pore Structure Fractal Characterization and Permeability Simulation of Natural Gas Hydrate Reservoir Based on CT Images

Pore Structure Fractal Characterization and Permeability Simulation of Natural Gas Hydrate Reservoir Based on CT Images

Experimental Study of the Wettability Characteristic of Thermally Treated Shale

Reservoir heterogeneity of the Longmaxi Formation and its significance for shale gas enrichment

Contact Info

Product

Resources

About