The permeability and diffusion coefficient of coal show multiscale characteristics due to the influence of multiscale pore sizes. The gas pressure will continuously decrease during the coalbed methane (CBM) extraction. However, there are contradictory perceptions in the effect of gas pressure on the diffusion coefficient and permeability. Therefore, it is essential to clarify the influence mechanism of gas pressure on multiscale diffusion-seepage. Diffusion-seepage experiments are carried out using particle coal and cylindrical coal without stress loading. Meanwhile, seepage experiments measured by the steady-state method are conducted under stress loading. The results show that the apparent diffusion coefficient is dynamically attenuated with time in the experiments of particle and cylindrical coal. A new model of multiscale dynamic apparent diffusion is proposed. The mechanism of gas flow in multiscale pores is elucidated. The multiscale pores determine the attenuation of the diffusivity and permeability of coal. The initial apparent permeability decreases and then increases with the increase of gas pressure, which is caused by the effect of gas pressure stretching and multiscale flow regime. Three patterns of permeability with gas pressure, monotonically increasing, monotonically decreasing, and U-shaped changes, will occur.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC10551909 | PMC |
| http://dx.doi.org/10.1021/acsomega.3c03806 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
A high fraction of inspired oxygen does not mitigate atelectasis-induced lung tissue hypoxia or injury in experimental acute respiratory distress syndrome.
Sci Rep
January 2025
Department of Pathology, Dokkyo Medical University School of Medicine and Graduate School of Medicine, 880 Kitakobayashi, Mibu, Shimotsugagun, Tochigi, 321-0293, Japan.
Although alveolar hyperoxia exacerbates lung injury, clinical studies have failed to demonstrate the beneficial effects of lowering the fraction of inspired oxygen (FO) in patients with acute respiratory distress syndrome (ARDS). Atelectasis, which is commonly observed in ARDS, not only leads to hypoxemia but also contributes to lung injury through hypoxia-induced alveolar tissue inflammation. Therefore, it is possible that excessively low FO may enhance hypoxia-induced inflammation in atelectasis, and raising FO to an appropriate level may be a reasonable strategy for its mitigation.
View Article and Find Full Text PDFEnhanced Prediction of CO-Brine Interfacial Tension at Varying Temperature Using a Multibranch-Structure-Based Neural Network Approach.
Langmuir
January 2025
Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education, School of Energy and Power Engineering, Dalian University of Technology, Dalian 116023, P. R. China.
Interfacial tension () between CO and brine depends on chemical components in multiphase systems, intricately evolving with a change in temperature. In this study, we developed a convolutional neural network with a multibranch structure (MBCNN), which, in combination with a compiled data set containing measurement data of 1716 samples from 13 available literature sources at wide temperature and pressure ranges (273.15-473.
View Article and Find Full Text PDFModeling of CO solubility and partial pressure in blended diisopropanolamine and 2-amino-2-methylpropanol solutions via response surface methodology and artificial neural network.
Sci Rep
January 2025
School of Chemical, Petroleum and Gas Engineering, Iran University of Science and Technology, P.O. Box: 16765-163, Tehran, Iran.
In this study, Response Surface Methodology (RSM) and Artificial Neural Networks (ANN) were developed to estimate the equilibrium solubility and partial pressure of CO in blended aqueous solutions of diisopropanolamine (DIPA) and 2-amino-2-methylpropanol (AMP). In this study, several key parameters were analyzed to understand the behavior of the aqueous DIPA/AMP system for CO capture. Including DIPA (9-21 wt%), AMP (9-21 wt%), temperature (323.
View Article and Find Full Text PDFInfluencing factors and quantitative prediction of gas content of deep marine shale in Luzhou block.
Sci Rep
January 2025
State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, 610500, China.
The exploration and development of deep marine shale gas has made significant breakthroughs, but factors influencing gas contents of deep marine shale are elusive, and quantitative prediction methods of gas content needs to be refined urgently. In this study, the deep marine shale of Longmaxi Formation in Luzhou area was taken as an example, vitrinite reflectance analysis, kerogen microscopy experiment, TOC content analysis, mineral composition analysis, gas content measurement, isothermal adsorption experiment, physical property analysis and argon ion polishing scanning electron microscopy experiment were carried out to find out factors affecting the gas content of deep marine shale, and a gas content prediction model has been worked out. Conclusions below have been reached: the content of adsorbed gas is mainly affected by Ro, TOC content, porosity, water saturation, clay mineral content, formation temperature and pressure; the content of free gas is mainly controlled by porosity, water saturation, formation temperature and pressure; according to the prediction models, the adsorbed gas content, free gas content and total gas content of each well were quantitatively calculated, and the study area was divided into Class I (with a total gas content ≥ 11 m/t), Class II (with a total gas content between 9 m/t and 11 m/t), and Class III (with a total gas content < 9 m/t) gas-bearing areas.
View Article and Find Full Text PDFNumerical analysis of the hydraulic fracture propagation behavior encountering gravel in conglomerate reservoirs.
Sci Rep
January 2025
State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, 610500, China.
Hydraulic fracturing, which forms complex fracture networks, is a common technique for efficiently exploiting low-permeability conglomerate reservoirs. However, the presence of gravel makes conglomerate highly heterogeneous, endowing the deformation, failure, and internal micro-scale fracture expansion mechanisms with uniqueness. The mechanism of fracture expansion when encountering gravel in conglomerate reservoirs remains unclear, challenging the design and effective implementation of hydraulic fracturing.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!