WEBMay 1, 2021 · The coal's permeability plays a crucial role in coalbed methane (CBM) extraction and coal seam CO 2 sequestration. An accurate understanding of permeability rebound and recovery is therefore essential. ... During the permeability evolution process, coal permeability rebound and recovery is an important behaviour. Currently, studies on .
WhatsApp: +86 18838072829WEBDec 1, 2023 · CBM, mostly methane, is predominantly adsorbed in the micropores of the coal matrix under in situ pressure, whereas the permeability of the reservoir is almost entirely provided by the cleats [3,4]. In the process of CBM extraction, a series of pores and fractures will be formed inside the roadway and surrounding rock under stress .
WhatsApp: +86 18838072829WEBMay 17, 2019 · 1 INTRODUCTION. Globally, Coalbed Methane (CBM), including coal mine methane (CMM) captured from the underground coal mining operations, is attracting growing attention mainly from the perspective of climate change caused by greenhouse gas (GHG) emission. 14 However, China has two additional and very compelling reasons .
WhatsApp: +86 18838072829WEBSep 19, 2023 · China's current energy consumption is primarily fueled by coal, increasing coal mining with growing energy demand. Coal and gas outburst accidents are common problems in coal mining, and prediction methods are fundamental for preventing such accidents. The gas emission characteristics of boreholes are a combination of .
WhatsApp: +86 18838072829WEBJul 1, 2016 · In this work, a fully coupled thermalhydraulicmechanical model with twophase flow for coalbed methane extraction was proposed including coal deformation, gas seepage, water seepage, and thermal transport governing equations. Different coupled models and the influence of several key factors on CBM extraction process were .
WhatsApp: +86 18838072829WEBJul 1, 2016 · Although the interaction of gas and coal has been comprehensively investigated in coalbed methane (CBM) extraction process, fewer scholars have taken the effect of temperature and groundwater into account, which brought a large deviation for CBM extraction design. In this study, a fully coupled thermal–hydraulic–mechanical .
WhatsApp: +86 18838072829WEBNov 1, 2022 · Besides, they studied the variation laws of coal seam permeability, gas pressure and flow rate during heat injection. The following conclusion was drawn: the increase of coal seam temperature after heat injection can promote coalbed methane (CBM) desorption and improve coalbed permeability to realize the goal of increasing .
WhatsApp: +86 18838072829WEBOct 19, 2021 · The process of extracting coalbed methane (CBM) is not only of significance for unconventional energy supply but also important in mine safety. The recent advance in fracking techniques, such as carbon dioxide (CO 2) fracking, intensifies the complexity of stimulated coalbeds. This work focuses on developing a fully coupled .
WhatsApp: +86 18838072829WEBNov 22, 2023 · Based on the basic geological data and production data of coalbed methane wells in the Shouyang Block, the characteristics and influencing factors of coalbed methane well production were analyzed, and the primary controlling factors were identified by the grey correlation method. The results show that the average daily gas .
WhatsApp: +86 18838072829WEBDec 1, 2019 · These results provided important references for the study of coalbed methane extraction. However, these papers simplified the extraction process of CBM as a singlephase gas flow process. In other words, these papers neglected the effect of twophase flow process on coalbed methane extraction.
WhatsApp: +86 18838072829WEBFeb 1, 2000 · Review of technologies available to capture and use methane released from active and closed coal mines. Major coal basins of Asia (Kelafant and others, 1992) Types of well completion methods ...
WhatsApp: +86 18838072829WEBApr 17, 2019 · 1 INTRODUCTION. China is one of the countries with the largest coalbed methane resources. The exploration and development of CBM resources are of great significance for ensuring the safe production of the coal mine, improving the energy structure and purifying the environment in China. 13 CBM is a kind of unconventional .
WhatsApp: +86 18838072829WEBJul 1, 2019 · Coalbed methane (CBM) drainage in underground coal mining is of significance to guarantee mining process safety and bring valuable environmental benefits, as the drainage could help to eliminate methanerelated accidents, reduce greenhouse gas (GHG) emissions and provide a source of clean energy. Due to the .
WhatsApp: +86 18838072829WEBDec 28, 2023 · The injection of CO2 or N2 to displace CH4 in coal seams can improve coalbed methane (CBM) recovery. However, the migration pattern of these gases in the coal matrix is disputed as the Fick ...
WhatsApp: +86 18838072829WEBSep 6, 2022 · In the past, during coal mining and utilization process, a large amount of coalbed methane was directly discharged into the atmosphere, which produced strong greenhouse effect. According to statistics (Yang 2009 ), every year in China, billion m 3 of methane is emitted to the atmosphere and 34% of that is caused by coal mining.
WhatsApp: +86 18838072829WEBJan 1, 2023 · In the technology of Supercritical Carbon Dioxide Enhanced Coalbed Methane (ScCO 2ECBM), permeability evolution is a critical factor influencing the widespread appliion of this theoretical studies primarily focus on factors like pressure, but the influence of phase pressures on permeability evolution .
WhatsApp: +86 18838072829WEBCoalbed methane (CBM) is a valuable clean energy source that is associated with underground mining disasters such as coal and gas outbursts. Therefore, as a byproduct gas of coal, efficient extraction of CBM is beneficial for adequate resource utilization, environmental protection, However, drilling in soft coal seams with CBM accumulation .
WhatsApp: +86 18838072829WEBPermeability rebound and recovery are pivotal in determining the efficacy of coalbed methane (CBM) extraction and the impact of superheated water injection during thermally enhanced CBM extraction. Existing research predominantly focuses on the roles of effective stress and methane desorption shrinkage, often neglecting the critical .
WhatsApp: +86 18838072829WEBOct 15, 2018 · Coal permeability rebound and recovery severely affect the efficiency of coalbed methane extraction and CO 2 storage capability of coal seams, but theoretical research on it is insufficient now. Besides, ambiguity still remains in evolution laws of coal permeability rebound and recovery pressure with the change of various influencing factors.
WhatsApp: +86 18838072829WEBDec 28, 2023 · During a CBM extraction process, methane gas in a coal matrix subsystem diffuses continuously into fractures driven by the FGDG, while the outermost layer of the matrix subsystem is the methane mass transfer boundary between the two. ... Flow of coalbed methane to a gallery. Transport in Porous Media, 41, 1–16. Article .
WhatsApp: +86 18838072829WEBApr 20, 2022 · This paper proposes an improved coupled modeling method for coalbed methane extraction after hydraulic fracturing. Based on the damage mechanics theory, we introduce a state damage variable to record the damage changes at different times and construct the coupling governing equations of the seepage field and solid mechanics .
WhatsApp: +86 18838072829WEBJul 1, 2022 · 1 INTRODUCTION. Coalbed methane (CBM) is an unconventional methane resource with plentiful reserves and is considered a source of clean energy. Global recoverable CBM reserves are estimated at 49 × 10 12 m 3, which accounts for % of the world's unconventional methane resources. 13 Moreover, to prevent and control .
WhatsApp: +86 18838072829WEBOct 1, 2017 · 1. Introduction. Improvements in the understanding of coalgas interactions have altered the manner in which we treat coalbed methane (CBM): from eliminating its threat as a mining hazard to tapping its potential as a clear energy (Chen et al., 2012, Karacan et al., 2011; Li et al., 2015, Liu et al., 2011, Moore, 2012).Compared with .
WhatsApp: +86 18838072829WEBMar 7, 2021 · A novel multilateral well for coalbed methane extraction was proposed in the study. There is a main wellbore at the longitudinal center of coal seam and four lateral wells at the horizontal center in the multilateralwell system. Compared with traditional drainage holes, multilateralwell system has a better performance on coalbed methane .
WhatsApp: +86 18838072829WEBFeb 15, 2020 · Teng et al. put forward that temperature is the key factor affecting CBM extraction, and coal bed heating can effectively promote methane desorption and ... Occurrence mechanism and risk assessment of dynamic of coal and rock disasters in the lowtemperature oxidation process of a coalbed methane reservoir. Energ Fuel, 31 (4) .
WhatsApp: +86 18838072829WEBMay 30, 2018 · In multibranch horizontal well CMB extraction process, the matrix shrinkage caused by temperature reduction and methane desorption dominates, the permeability continues to increase. Due to the effect of temperature on the amount of gas adsorbed by coal, the CH 4 production decreases with the increase of initial reservoir .
WhatsApp: +86 18838072829WEBJun 1, 2017 · In this study, a gas–solid coupling model is used to conduct a numerical solution for coalbed methane migration in the process of underground methane extraction. The effects of the diffusion and suction negative pressure on the methane migration and extraction are studied. Key findings are summarized as follows: (1)
WhatsApp: +86 18838072829WEBFeb 26, 2022 · First, CBM, a natural gas which contains 9095% methane, gets absorbed and stored in coal seams. India has a coal reserve of 285 billion tonnes, the world's fourthlargest coal reserves. and thus, holds significant prospects for exploration and exploitation of CBM. Second, the progress in CBM so far has remained slow.
WhatsApp: +86 18838072829WEBSep 22, 2022 · Coalbed methane (CBM) drilling and completion technologies (DCTs) are significant basis for achieving efficient CBM exploration and exploitation. Characteristics of CBM reservoirs vary in different regions around the world, thereby, it is crucial to develop, select and apply the optimum DCTs for each different CBM reservoir. This paper firstly .
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