Methane diffusivity controls matrix-to-cleat gas transfer in coalbed methane reservoirs and varies with pore structure, pressure, and water saturation. A three-dimensional pore–throat network combines steady-state Fickian transport with invasio...
Sorption-enhanced methanation has consequent advantages compared to conventional methanation approaches; namely, the production of pure methane and enhanced kinetics thanks to the application of Le Châtelier’s principle. In this paper, we...
Knowledge of the gas adsorption rate and diffusion characteristics in shale are very important to evaluate the gas transport properties. However, research on methane adsorption rate characteristics and diffusion behavior in shale is not well establis...
Coalbed methane (CBM) content is generally estimated using the isotherm theory between pressure and adsorbed amounts of methane. It usually determines the maximum content of adsorbed methane or storage capacity. However, CBM content obtained via labo...
The massive emission of low concentrations (≤0.5%) of methane (CH4) from ventilation roadways results in resource waste and environmental pollution. To mitigate these emissions, an enrichment tower for low-concentration methane is designed, and segre...
The analysis of phenomena related to gas transport in hard coal is important with regard to the energetic use of coal bed methane (CBM), the reduction of greenhouse gas emissions to the atmosphere (CO2) and the prevention of natural hazards such as m...
This work examined the effects of secondary annular flow area on flame stability in an experimental diffusion flame burner. The burner was composed of a horizontally mounted, rectangular chamber that utilized a retractable spark plug for ignition and...
CO2 methanation with renewable hydrogen is a promising strategy for carbon valorization and synthetic natural gas (SNG) production. However, the molecular mechanisms behind catalyst-dependent adsorption and mass transport in zeolite-confined spaces a...
China has abundant deep coalbed methane (CBM) resources; however, high temperature, stress, and reservoir pressure complicate the gas adsorption–desorption–diffusion–seepage processes, severely restricting the development of deep CB...
The performance of diffusion flame (DF) burners strongly depends on how effectively combustion gases mix and retain heat, yet the influence of exhaust nozzle geometry on these processes remains insufficiently characterized. This study examines how va...
Mercury intrusion porosimetry (MIP) has been utilized for decades to obtain the pore size, pore volume and pore structure of variable porous media including inorganic rocks and organic rock (e.g., shales and coals). Diffusivity and permeability are t...
This study aims to qualitatively and quantitatively assess the ability of the flow solver “reactingFoam” of the open-source OpenFOAM software v.2506 for a control-volume-based computational fluid dynamics (CFD) solver in treating the reac...
Eutrophication is prevalent in urban lakes; however, a knowledge gap exists regarding eutrophication influences on carbon dynamics in these ecosystems. In the present study, we investigated the carbon dioxide (CO2) and methane (CH4) concentration and...
The article presents the results of an experimental comparison of methane transport in the pore structure of a membrane catalyst under isothermal and non-isothermal Knudsen diffusion conditions. It is shown that under the conditions of non-isothermal...
Here, we analyze the degassing process of a byproduct (methane) formed during the peroxide-induced crosslinking of polyethylene. A diffusion model based on Fick’s law is used to obtain the controlling factors of degassing in a crosslinked polye...
Underground hydrogen storage in depleted gas reservoirs has emerged as a key technology for large-scale hydrogen energy storage. However, the occurrence state of hydrogen is governed by residual methane and reservoir mineral surfaces. This study comb...
Green ammonia has become an increasingly popular fuel in recent years because of its combustion process without carbon oxide release. Adding ammonia to methane fuel for co-combustion has become one of the important research topics in the current comb...
Horizontal wells with multi-stage fractures have been widely used to improve coalbed methane (CBM) production from coalbed methane reservoirs. The main focus of this work is to establish a new semi-analytical method in the Laplace domain and investig...
This study investigates the transport of methane released from gas hydrate decomposition through sedimentary layers to quantify its flux into the atmosphere, a critical process given methane’s role as a major greenhouse gas. A novel methodology...
Coalbed methane (CBM) is an unconventional natural gas primarily stored in coal seams. The efficient recovery of CBM mainly depends on the desorption and diffusion process. In this study, a stepwise wetting–corrosion method employing a combinat...
The leakage of methane from the subsurface on the coalfield or natural gas field invariably becomes an important issue nowadays. In notable addition, materials such as activated carbon, zeolites, and Porapak have been successfully identified as adsor...
The self-diffusion coefficients of carbonaceous fuels in a supercritical CO2 environment provide transport information that can help us understand the Allam Cycle mechanism at a high pressure of 300 atm. The diffusion coefficients of pure CO2 and bin...
The diffusion–adsorption behavior of methane in coal is an important factor that both affecting the decay rate of gas production and the total gas production capacity. In this paper, we established a pore-scale Lattice Boltzmann (LB) model coup...
The aim of this paper was to investigate the repeatability of sorption processes occurring in the coal-methane system during multiple measurement series. For research purposes, three granular samples of coal sorbent were used. The samples were subjec...
The article presents the experimental study analysis results of the methane combustion efficiency in a high-enthalpy oxygen-containing flow (HOF) inside of constant cross-section channel, finite along the length. The range of initial HOF enthalpies w...
Coals from the south-western part of the Upper Silesian Coal Basin have a strong outburst susceptibility. The objective of this study was to identify the influence of coalification degree on methane sorption and micro scale strength properties of 24...
The stratigraphic-diffusive type of gas hydrate system is formed by microbial methane produced in a shallow slope space when flowing laterally into hydrate stable zones and is worth studying for both energy supply and academic understanding. A deposi...
In order to study the importance of the diffusion mechanism of CH4 and CO2 in coal for the development of coalbed methane, the aim of this paper is to reveal the influence mechanism of pressure, temperature, water content and other factors on the mol...
With the rapid growth of the economy, people are increasingly reliant on energy sources. However, in recent years, the energy crisis has gradually intensified. As a clean energy source, methane has garnered widespread attention for its development an...
Biological methanation of carbon dioxide (CO2) using hydrogen (H2) offers a promising route for upgrading biogas and storing renewable energy within existing gas infrastructures. However, the low solubility of H2 in aqueous systems remains a major bo...
This article presents an analysis of kinetic studies of dry methane reforming (DRM) in a reactor with a membrane catalyst (RMC) in the modes of a contactor with “diffusion” and “forced” mass transfer. Comparison of the specifi...
(1) Background: New technologies involving gas hydrates under pre-nucleation conditions such as gas separations and storage have become more prominent. This has necessitated the characterization and modeling of the transport properties of such system...
Observing the vertical diffusion distribution of methane fugitive emissions from oil/gas facilities is significant for predicting the pollutant’s spatiotemporal transport and quantifying the random emission sources. A method is proposed for met...
CO2-enhanced coalbed methane recovery (CO2-ECBM) has been demonstrated as an effective enhanced oil recovery (EOR) technique that enhances the production of coalbed methane (CBM) while achieving the goal of CO2 sequestration. In this paper, the grand...
Reduction of nitric oxides (NOx) in aircraft engines and in gas turbines by lean combustion is of great interest in the design of novel combustion systems. However, the stabilization of the flame under lean conditions is a main issue. In this context...
Grand Canonical Monte Carlo (GCMC) simulation and Molecular Dynamics (MD) simulations were used to study the effects of temperature (310 K to 400 K), pressure (≤30 MPa) and water content (0 molecule/nm3 to 9 molecule/nm3) on the adsorption and dif...
This article presents research results into the application of an artificial neural network (ANN) to determine coal’s sorption parameters, such as the maximal sorption capacity and effective diffusion coefficient. Determining these parameters i...
The structure of methane/air tubular diffusion flames with
In this study, a 3D multicomponent multiphase simulator with a new fracture characterization technique is developed to simulate the enhanced recovery of coalbed methane. In this new model, the diffusion source from the matrix is calculated using the...
The pore structure of coal reservoirs is the main factor influencing the adsorption–diffusion rates of coalbed methane. Mercury intrusion porosimetry (MIP), low-pressure nitrogen adsorption (LP-NA), low-pressure carbon dioxide adsorption (LP-CA), and...
Mixtures of hydrogen with common hydrocarbon fuels are considered viable for reducing carbon footprint in modern industry, power production, and transportation. The addition of hydrogen alters the kinetics and thermophysical properties of the mixture...
Adsorption and diffusion are the key factors affecting coalbed methane (CBM) accumulation, resource assessment and production prediction. To study the adsorption and diffusion mechanism of Fukang low-rank coal at the microscopic level, samples of Fuk...
Rapid industrialization and the influx of human resources have led to the establishment of industrial complexes near urban areas, exposing residents to various air pollutants. This has led to a decline in air quality, impacting neighboring residentia...
Global energy demand escalates the interest in effective and durable catalytic systems for the dry reforming of methane (DRM), a process that converts CO2/CH4 into H2/CO syngas. Porous silica-supported nickel (Ni) catalysts are recognized as a promis...
During coalbed methane production, water plays a crucial role in methane adsorption and diffusion; however, the adsorption and diffusion of methane in water-bearing low-rank coal remain difficult to characterize synergistically within a unified molec...
Measurements of nuclear spin relaxation times over a wide temperature range have been used to determine the interaction energies and molecular dynamics of light molecular gases trapped in the cages of microporous structures. The experiments are desig...
This study numerically investigates the critical fuel concentration and flammable regions of methane–air and methane oxy-fuel counterflow diffusion flames. The goal is to determine the effects of strain rate, oxidizer composition, and radiative...
Variable-flow displacement has been effectively used to enhance oil recovery; however, it has rarely been investigated for coalbed methane production, and the CH4 diffusion laws in this process are not clear. In this paper, we carried out a study on...
Gas-fired boilers, gas stoves, and wall-mounted gas boilers are the main consumers of gas fuel, but they generally encounter problems when operating at high altitudes, such as reduced thermal efficiency and increased pollutant emissions. Previous stu...
Experimental measurements of midwave infrared thermal images of methane diffusion flames at different concomitant flow velocities were obtained as snapshot data to analyze the flame scintillation effect. The spectral proper orthogonal decomposition (...
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