WEBApr 19, 2022 · As a result, it is difficult for the coal seam sealing process to meet engineering quality sealing requirements, which results in problems such as low gas concentration during the extraction process. In this paper, based on the analysis of coal pore and fissure characteristics, and in view of the current situation of gas drainage and .
WhatsApp: +86 18037808511WEBMay 1, 2016 · Coal seam gas (CSG) is a growing industry in Queensland and represents a potential major employer and deliverer of financial prosperity for years to come. CSG is a natural gas composed primarily of methane and is found trapped underground in coal beds. During the gas extraction process, significant volumes of associated water are also .
WhatsApp: +86 18037808511WEBFeb 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) .
WhatsApp: +86 18037808511WEBIn industrial chemistry, coal gasifiion is the process of producing syngas—a mixture consisting primarily of carbon monoxide (CO), hydrogen (H 2), carbon dioxide (CO 2), methane (CH 4), and water vapour (H 2 O)—from coal and water, air and/or oxygen.. Historically, coal was gasified to produce coal gas, also known as "town gas".Coal gas .
WhatsApp: +86 18037808511WEBThe initial phase of CSG production usually involves the extraction of formation water from the coal seams in order to reduce the water pressure and release gas from the coal. At the surface, water in the gas is separated and piped elsewhere for use or further treatment. Gas from underground coal gasifiion (UCG) is sometimes confused with ...
WhatsApp: +86 18037808511WEBOct 26, 2023 · In order to develop precise hole placement technology for gas extraction, this paper combines industrial testing, the evolution law of coal rock damage permeability, and the coal doublepore doublepermeability model; establishes a coupling model of the coal damage deformation field and matrixfracture double diffusion seepage field; and .
WhatsApp: +86 18037808511WEBAug 16, 2011 · As explained by Dennis Cooke at the Conversation, a major community concern about coal seam gas extraction is the process of fracking. Under this process, vast amounts of highpressure water ...
WhatsApp: +86 18037808511WEBJan 1, 2023 · Coal permeability is a crucial property for coal seam gas production. In previous studies, it was assumed that both matrix blocks and coal bridges share an average equalized gas pressure.
WhatsApp: +86 18037808511WEBJun 14, 2023 · The FLAC 3D numerical simulation software simulated the gas extraction process from the coal seam using directional boreholes. Optimal drilling parameters were determined by analyzing plasticity, stress, and enhanced permeability zone distribution patterns during gas extraction with different borehole radii. A .
WhatsApp: +86 18037808511WEBSep 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. ... Zhang J, Liu Y, Ren P, Han H, Zhang S (2021) A fully multifield coupling model of gas extraction and air leakage for inseam borehole. Energy Rep 7:1293–1305
WhatsApp: +86 18037808511WEBApr 1, 2013 · The effects of directional compaction, nonDarcy flow and anisotropic swelling on the extraction of natural gas in coal seam reservoirs are important but not well understood so far. This paper investigated these combined effects through a numerical model which fully couples the interactions of coal seam deformation, anisotropic gas .
WhatsApp: +86 18037808511WEBNov 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 .
WhatsApp: +86 18037808511WEBMay 1, 2016 · Based on the multiphysics field theory, the hydraulicmechanical coupling model of gas extraction in the unloading coal seam was established, and the gas extraction process by drilling borehole in ...
WhatsApp: +86 18037808511WEBMay 2, 2018 · The temperature of the coal seam will be lower than ambient temperature after gas extraction because of the endothermic process, as a result, heat energy flows from the environment into the coal seam. ... Liu,, Cheng,, Jiang,, Li, W., Jin, K.: Interactions between coal seam gas drainage boreholes and the impact of such on ...
WhatsApp: +86 18037808511WEBFeb 5, 2024 · More and more gas extraction in deep coal seam is conducted under extreme geological conditions. The coal permeability determines the efficiency of gas extraction. To research the evolution of permeability and gas seepage in deep coal seam under threedimensional (3D) stress condition, a permeability model (DCTDS model) .
WhatsApp: +86 18037808511WEBApr 19, 2022 · As a result, it is difficult for the coal seam sealing process to meet engineering quality sealing requirements, which results in problems such as low gas concentration during the extraction process.
WhatsApp: +86 18037808511WEBJan 19, 2016 · Biochemical reactions associated with this process transform the organic matter into humic substances, which are the precursors of coal macerals. ... an isotherm should be obtained from each major coal seam. These isotherms can be used to determine the saturation state and estimate a recovery factor by comparing the expected gas .
WhatsApp: +86 18037808511WEBMay 26, 2023 · Coal as the main energy source in the process of industrialization is necessary to ensure rapid economic development (Balat et al. 2010; Wang et al. 2020; Xiang et al. 2021).However, the coal bed conditions are complex in China (, high gas content) potential causing ous safety problems in the process of coal mining, especially .
WhatsApp: +86 18037808511WEBApr 1, 2013 · 1. Introduction. Reservoir compaction may accentuate the nonDarcy flow and induce the anisotropy of permeability during both conventional gas production and unconventional gas (such as coal seam gas) extraction (Clarkson et al., 2007, Majewska et al., 2010, Zeng et al., 2003).The gas flow in porous media is usually pressuredriven .
WhatsApp: +86 18037808511WEBThis welldeveloped fracture network can significantly enhance the rock mass permeability and the reservoir gas extraction. Overall, it can be concluded that the combined characteristics of LCO2 (high compressibility, low viscosity) lead more controllable and effective coal seam hydraulic fracturing process compared with the water based ...
WhatsApp: +86 18037808511WEBMay 1, 2022 · The process of deformation and failure of coal sample ZZ3 was simulated using the ... The underground coal seam gas extraction project is ... Based on the Darcy's law in the flow of gas in the ...
WhatsApp: +86 18037808511WEBApr 1, 2023 · Zhangcun coal mine is loed at the northeast of Changzhi City in Shanxi Province, China. The 3# coal seam is characterized by thickness of ∼6 m, high gas content of m 3 /t, and low permeability of × 10 −17 m shown in Fig. 3 (a), gas extraction is adopted to deplete gas from coal seam, and the inseam boreholes with .
WhatsApp: +86 18037808511WEBApr 1, 2022 · Section snippets Basic assumptions. Coal seams generally contain both coal matrix and fractures, which are typical of dualporosity media [52]. To simplify the methane gas flow process in coal as much as possible, we refer to previous literature [12], [51] when building the dualporosity model of coal bodies and make the following .
WhatsApp: +86 18037808511WEBDOI: / Corpus ID: ; Study on gas seepage from coal seams in the distance between boreholes for gas extraction article{Zhao2018StudyOG, title={Study on gas seepage from coal seams in the distance between boreholes for gas extraction}, author={Dan Zhao and Jian Liu and Jingtao Pan}, journal={Journal of Loss .
WhatsApp: +86 18037808511WEBNov 1, 2022 · The above methods of strengthening coal seam gas extraction introduces one or more gases into the coal seam. The influence of such methods on coal seam gas migration still needs further discussion. ... In summary, other key scientific issues involved in the process of coal mine gas extraction are to reveal the flow state of fluid in the cross ...
WhatsApp: +86 18037808511WEBDec 29, 2023 · In order to increase the permeability of low permeability and high gas coal seam and improve the efficiency and utilization of gas extraction, the permeability enhancement technology of deep hole presplitting blasting is proposed, and the mechanism of blasting induced cracking of deep hole presplitting blasting is analyzed. .
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