WEBJan 1, 2023 · A Nonequilibrium model for coal multiphysics. In this section, a nonequilibrium coal multiphysics model is formulated, which includes three governing equations representing mechanical deformation of coal seams, gas flow in the fractures and matrixfracture mass transport, respectively. The new nonequilibrium porosity and permeability .
WEBFeb 11, 2022 · Gas is one of the main factors causing coal mine accidents in China. Understanding the mechanism of the influence of mine pressure on coal seam gas emission has important theoretical guiding significance for coal mine enterprises to be able to control gas. This paper chose the 72,909 working face in the Du'erping coal mine as .
WEBManaging produced water from coal seam gas projects: impliions for an emerging industry in Australia Environ Sci Pollut Res ... produced water has been defined as water that is brought to the land surface during the process of recovering methane gas from coal seams and includes water sourced from CSG wells as well as flowback water ...
WEBJan 1, 2017 · The adsorbed gas in the coal seam takes more than 80% of the total, while the content of adsorbed gas mainly depends on the porosity of coal, gas pressure and temperature. ... We combine the MATLAB and the COMSOL Multiphysics to obtain numerical solution and achieve the evolution process of coal and gas outburst .
WEBMar 6, 2024 · Thick coal seam fracture stimulations were conducted to enhance pregas drainage efficiency through the use of a highly pressurized multidischarge carbon dioxide gas fracturing technique. This method also offers potential as a strategy for carbon dioxide sequestration, aiding in the reduction of atmospheric carbon dioxide levels and thereby .
WEBFeb 25, 2021 · Coal bed methane (CBM) is a primary clean energy source found in coal seams. The recovery ratio of CBM is very low, especially with ground extraction, due to the strong adsorption of CH4 on the pores and fissures of coal and low permeability of the coal bed. On the basis of the theory of energy balance, a theory of enhanced CBM (ECBM) .
WEBJul 11, 2022 · Secondly, the mechanism of N 2 injection to enhance coal seam gas drainage (N 2ECGD) was discussed: with the gradual decrease of gas pressure in the drainage process, coal seam gas enters a lowpressure state, the driving force of flow is insufficient, and the drainage enters the exhaustion period. The nitrogen injection .
WEBOct 1, 2020 · This study used computer simulation to select appropriate process designs to make coal seam gas (CSG) associated water comply with beneficial reuse regulations. ... Development and commercialization of coal seam gas (CSG) deposits has primarily occurred within the past 30 years in countries such as USA, Australia, Canada, China, .
WEBNov 6, 2014 · Enhanced coal bed methane recovery (ECBM) is the process in which a displacing gas, such as CO 2 (CO 2ECBM) or N 2 (N 2ECBM) is introduced into the coal seam through an injection well and held there for a sufficient period to enable a substantial amount of methane to be desorbed from the surfaces of the coal seam. Following the .
WEBFeb 1, 2024 · Abundant industrial experiences have shown that directional air drilling technology is effective for gas drainage when drilling broken and soft coal seams. In this paper, the Eulerian–Eulerian model was used to simulate the gas–solid twophase flow behavior of compressed air transporting coal dust in broken soft coal seams. The .
WEBDownload scientific diagram | Coal seam gas production process (created by the author using data from Rice and Nuccio 2000) from publiion: A study on the carbon dioxide injection into coal seam ...
WEBJul 1, 2012 · II102 mining area overall is a monoclinic structure, and the vertical elevation is from −475 to −700 main mining seam is #10 coal seam belonged to the nonoutburst prone coal (Measured results of gas basic parameters are shown in Table 2), and the average thickness is m. Roof lithology is generally mediumfine sandstone, and .
WEBJul 16, 2019 · Coal and gas outburst is a kind of dynamic phenomenon and mainly driven by gas pressure. 12, 13 The coal seams are prone to be fractured, and outburst process will be largely accelerated with the presence of high gas pressure. 14 By and large, the phenomenon of outbursts is the process of coal energy dissipation, 15, 16 which is .
WEBApr 1, 2013 · The blasting damage of coal seam, together with the subsequent gas migration can be captured as a fully coupled process among coal seam damage and gas flow. In this respect, the formation of blasting damaged zone is considered as the combined contribution of blasting stress wave and quasistatic explosion gas pressure, based on .
WEBJul 28, 2023 · Coal seam gas extraction is not only a source of clean and natural energy but also a means to address the pressing issue of gas control . Undoubtedly, methane ... Q. Simulation on the temperature evolution law of coal containing gas in the freezing coring process. J. China Coal Soc. 2021, 46, 199–210. [Google Scholar] Wang, X.; Zhou, F.; .
WEBJun 21, 2023 · Coal Seam Gas. Coal Seam Gas (CSG) is a naturally occurring methane gas found in most coal seams and is similar to conventional natural gas. In Australia the commercial production of CSG commenced in 1996 in the Bowen Basin, Queensland. Since then production has increased rapidly, particularly during the first decade of the 21st .
WEBSep 19, 2023 · The gas migration process in the coal seam can be divided into gas desorption and diffusion in the matrix to the fractures and then into the borehole through seepage. The mass exchange between coal matrix and fracture follows Fick's law of diffusion (Yu et al. 2007):
WEBThe amount of gas retained in coal depends on a number of factors such as the rank of coal, the depth of burial, the immediate roof and floor to the coal seam, geologic anomalies, tectonic pressures, and temperature prevailing at the end of the coalifiion process. In general, the higher the rank of coal and the greater the depth of coal seam ...
WEBJun 30, 2013 · The major steps for this drilling and completion technique are. Drilling the production hole to the top of the coal seam. Running and cementing casing. Drilling a hole through the coal seam. Increasing the diameter of the hole by a technique known as underreaming (Fig. 1)
WEBCoal seam gas pressure is the core index of coal mine gas disaster prevention and control. Research on active nitrogen injection pressure measurement can effectively shorten the pressure measurement time and is of great significance to improve the pressure measurement efficiency. The purpose of this paper is to study the variation in gas .
WEBJul 17, 2023 · In order to assist model derivation, the following hypotheses were tested: (1) the coal deformation is infinitesimal and elastic; (2) gas is an ideal gas, and gas flow in the coal seam is an isothermal process; (3) gas flow in the matrix or fracture is Darcy seepage; and (4) gas flow between matrix and fracture follow Fick's law.
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