WEBFeb 5, 2020 · Coal seams can also serve as an alternative natural gas source. It is recognized as coal seam gas or termed coal bed methane when natural gas is collected from a coal seam. The gas sticks to the surface of deposits of underground coal, normally lined with water, and forms a thin film on the coal surface because of the water's pressure.
WhatsApp: +86 18037808511WEBNov 24, 2020 · The coal seam gas content in the east and west increases from 5 to m 3 /t. During the roadway excavation of 4304 and 4306 working faces in the eastern mining area, the coal bursts were frequent, the gas emission volume suddenly appeared and fluctuated from large to small, and the antiburst indiors continuously exceeded .
WhatsApp: +86 18037808511WEBDec 15, 2023 · The Independent Expert Scientific Committee on Unconventional Gas Development and Large Coal Mining Development (IESC) is a statutory committee of leading scientists that independently advises government regulators on the impacts that unconventional gas and large coal mining developments may have on Australia's water .
WhatsApp: +86 18037808511WEBMay 1, 2020 · To quantify the coupling relationship between gas pressure and stress in the mining process, relation curves of coal seam stress and the gas pressures of the matrix and fracture with distance from the coal wall of the working face are illustrated in Fig. 7. Download : Download highres image (335KB) Download : Download fullsize image; .
WhatsApp: +86 18037808511WEBOct 1, 2023 · The gas content is crucial for evaluating coal and gas outburst potential in underground coal mining. This study focuses on investigating the insitu coal seam gas content and gas sorption capacity in a representative coal seam with multiple sections (A1, A2, and A3) in the Sydney basin, where the CO 2 composition exceeds 90%. The fast .
WhatsApp: +86 18037808511WEBAug 4, 2023 · Gas extraction is the main method to reduce gas content and eliminate gas accidents, and due to the influence of mining stress in the coal seam mining process, there are elastic damage zones and plastic damage zones of coal seams [3, 7]. Therefore, in order to improve the efficiency of gas extraction, it is necessary to study the elastic ...
WhatsApp: +86 18037808511WEBFeb 13, 2023 · The evolution of fissures and permeability associated with mining of the upper protective layer of the coal seam is crucial for pressure relief gas drainage of the underlying seam. To understand ...
WhatsApp: +86 18037808511WEBNov 1, 2020 · Abstract. Severe gas disasters in deep mining areas are increasing, and traditional protective coal seam mining is facing significant challenges. This paper proposes an innovative technology using soft rock as the protective seam in the absence of an appropriate coal seam. Based on the geological engineering conditions of the new .
WhatsApp: +86 18037808511WEBJan 1, 2017 · The protective seam mining and gas drainage technique applied to strong coal and gas outburst dangers coal mine [15]. ... We combine the MATLAB and the COMSOL Multiphysics to obtain numerical solution and achieve the evolution process of coal and gas outburst dynamic system [27]. The basic procedure is shown in Fig. 6. .
WhatsApp: +86 18037808511WEBDec 14, 2019 · The mineable and locally mineable seams in Lin Hua Coal Mine are 5 seams, numbered 4, 5, 9, 13 and 15 seams, all of which are gas outburst seams. M9 is the main coal seam, and the maximum content of gas in this coal seam is m 3 /t. It is dangerous and difficult to extract. Table 1 is gas test table of 9 # coal seam.
WhatsApp: +86 18037808511WEBMay 1, 2019 · With the same stress state,the larger the water pressure is,the larger the volume strain of coal is. During the mining process of protected coal seam mining,the initial confining pressure of M ...
WhatsApp: +86 18037808511WEBFeb 1, 2018 · Methane gas drainage is an effective method to ensure miningprocess safety and deliver greater environmental benefits through reducing greenhouse gas (GHG) emissions. ... During and after the mining of the overlying coal seam, gas drainage in the relieved underlying seam should be conducted, of which, there are mainly two purposes: .
WhatsApp: +86 18037808511WEBMay 1, 2011 · At a typical gassy coal mine, ventilation air may contain –1% methane, whereas gas drained from the seam before mining can contain 60% to more than 95% methane depending on the presence of other gasses in the coal seam. Gas drained from fractured formations above mined seams (gobs), on the other hand, may contain .
WhatsApp: +86 18037808511WEBMay 1, 2021 · Incorporating the impacts of coal mining and coal seam gas Changes in baseflow. As outlined in Section, a standalone surface water model is unlikely to be capable of accurately estimating changes in baseflow discharge associated with groundwater extraction and depressurisation.
WhatsApp: +86 18037808511WEBCoal mining Underground, Surface, Drilling: The various methods of mining a coal seam can be classified under two headings, surface mining and underground mining. Surface and underground coal mining are broad activities that incorporate numerous variations in equipment and methods, and the choice of which method to use in .
WhatsApp: +86 18037808511WEBMay 25, 2020 · The measures for predrainage of coal seam gas by drilling along the seam are mainly applicable to areas with coal seams exhibiting stable occurrence and good permeability. FIGURE 6. Open in figure viewer PowerPoint. Sketch map of bedding borehole method (Wang 2014) ... The process of coal seam mining inevitably leads to .
WhatsApp: +86 18037808511WEBDec 16, 2023 · Longwall mining is a widely used method for excavating underground coal seam. The overlying strata will subside and sequentially fracture after underground mining disturbance, resulting in caving, separation, and collapse of overburden (Palchik 2003; Wei et al. 2022).The three zones will progressively occur and extend vertically from coal .
WhatsApp: +86 18037808511WEBMar 11, 2021 · The Chinese "Coal Mine Safety Regulations" states that the H 2 S concentration of coal mine gas is considered abnormal if it concentration is greater than ppm 1, 2, 3. Such concentrations ...
WhatsApp: +86 18037808511WEBJul 28, 2023 · Determining a method whereby the safety level of the coalmining process can be improved while ensuring acceptable levels of coal production is a problem to which we must attach great importance. ... Wang, B. Experimental Study on Rapid Determination Method of Coal Seam Gas Content by Indirect Method. Processes 2023, 11, 925. .
WhatsApp: +86 18037808511WEBJul 1, 2020 · However, deformation in the coal matrix is not equal to fracture deformation, meanwhile, the coal mining process causes obvious plastic deformation. Therefore, in this work ... A fully coupled coal deformation and compositional flow model for the control of the premining coal seam gas extraction. International Journal of Rock Mechanics and ...
WhatsApp: +86 18037808511WEBNov 3, 2023 · The indirect method is to predict the gas content of coal seam by gas emission and adsorption isotherm curve 14,15,16. Permeability is a key factor to determine the development process and ...
WhatsApp: +86 18037808511WEBFeb 9, 2023 · In engineering practice, the mining of F 15 coal had a great impact on the roadway of the E coal seam, which showed that the mining action of advance mining of the F 15 coal seam had an impact on the E coal seam. It could make full use of the pressure relief effect of coal seam mining in the E coal seam to control the gas in .
WhatsApp: +86 18037808511WEBSep 29, 2016 · The protective seam mining has become one of the most important measures of preventing outburst hazard in the deep outburst coal seam. The comprehensive study of gas permeability change rules and gas seepage rules of the protected seam close to the protective seam in the mining process of the protective .
WhatsApp: +86 18037808511WEBJul 11, 2016 · Based on the miningenhanced permeability model, the effect of damage on the permeability is considered and the 3D finite element program is established, which can be used to calculate the damage and permeability characteristics of coal seam during the mining process. 2. The gas permeability test of coal samples was conducted.
WhatsApp: +86 18037808511WEBNov 18, 2023 · Coal and gas outburst is a mine gas dynamic phenomenon, which threatens the safety production of coal mines (Wang and Cheng 2023; Ma et al. 2020).Since the world 's first coal and gas outburst occurred in the Issac mine of the French Ruhr coal field in 1834, coal and gas outbursts have occurred in 18 countries, including .
WhatsApp: +86 18037808511WEBSep 12, 2023 · The Conversation.. A study from 2017 found that air pollution from CSG mining could pose a significant threat to public health, particularly in terms of respiratory diseases A Ali, V Strezov, P Davies, I Wright (2017, Jul 21). Environmental impact of coal mining and coal seam gas production on surface water quality in the Sydney basin, .
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