WEBDec 15, 2021 · 1. Introduction. According to the Global Energy Statistical Yearbook 2020, the total proven reserves of natural gas worldwide amount to trillion m total production is billion m 3, and the total consumption is 3, billion m 3 with a share of % in primary energy [1].Coal seam gas (CSG) accounts for 6%–9% of .
WhatsApp: +86 18838072829WEBMay 10, 2024 · During the gas extraction drilling process, especially the soft coal seam drilling process, due to the constraints of geological conditions, technical conditions, and other factors, it is easy to encounter stuck holes, blowout, lost circulation, and hole collapse, which affect the realization of efficient gas management. In the petroleum industry, .
WhatsApp: +86 18838072829WEBSep 2, 2014 · This animation provides an overview of the coal seam gas extraction process, from drilling the well to what happens to the extracted gas and water. Also expl...
WhatsApp: +86 18838072829WEBJan 13, 2023 · The method of predicting whether it is an outburst danger zone stipulated in the "Coal and Gas Outburst Prevention Rules" is based on the coal seam gas pressure of MPa and the content of 8 m 3 / t as the critical value. Reducing the gas pressure of coal seam to MPa during the extraction process is an important discriminant index.
WhatsApp: +86 18838072829WEBOct 1, 2019 · The selection of proppants is critical in the coal seam gas extraction process, where the softer coal rock surface restricts the use of high strength proppants due to its vulnerability of embedding into the surface. 2) coal properties – elastic modulus of coal is the most important factor deciding the proppant behaviour in the extraction ...
WhatsApp: +86 18838072829WEBJun 7, 2022 · new technology of largediameter mechanical cavemaking to promote gas extraction. in a coal seam. This technology mainly uses the pressure of a water injection pump. to control the automatic ...
WhatsApp: +86 18838072829WEBJun 1, 2024 · At present, a large area is drilled through the layer in the floorrock roadway to predrain coal seam gas as an outburst prevention measure [45, 46]. However, during the later stages of gas extraction, the gas extraction flow and gas concentration are low, and the extraction efficiency is also low [47].
WhatsApp: +86 18838072829WEBNov 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 18838072829WEBApr 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 18838072829WEBSep 15, 2023 · Liquid CO 2 injection into coal seam for CH 4 displacement is one of the important means to strengthen gas extraction and carbon sequestration in recent years. After liquid CO 2 is injected into coal seam, physical and chemical interactions occur with coal through the process of "liquid phase seepagephase transformation supercharging .
WhatsApp: +86 18838072829WEBDec 21, 2017 · Coal seam gas extraction process (Sajjad et al. 2015). To enlarge fractures and fissures, the compressed liquid, which is a blend of water, sand, and some additives, is driven into the coal seam. The coal seam depressurizes by the process, which permits the trapped gas to become free.
WhatsApp: +86 18838072829WEBSep 1, 2015 · Despite long extraction times, the amount of extracted gas is very low due to low gas permeability in Chinese coal seams. Therefore, the coal seam requires significant structural changes to improve the efficiency of the gasextraction process and reduce the gasextraction time (Zhou et al., 2012).
WhatsApp: +86 18838072829WEBApr 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 18838072829WEBSep 20, 2019 · Coal Seam Gas: Evaluation, Extraction, and Environmental Issues. September 2019. DOI: /. In book: Sustainable Energy and Environment () Authors: Debadutta Mohanty ...
WhatsApp: +86 18838072829WEBApr 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 18838072829WEBFeb 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 18838072829WEBOct 1, 2020 · Typically, the gas reserves are loed in coal seams which are several hundred meters below ground. The extraction process involves depressurization of the seams [3], which results in the collection of substantial amounts of CSG associated water which is saline in character [4].
WhatsApp: +86 18838072829WEBAug 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 18838072829WEBApr 19, 2022 · Coal is affected by the concentrated stress disturbance of mining, the disturbance of drilling hole formation, and the concentrated stress of coal shrinkage and splitting of gas desorption from the hole wall; these result in a large number of secondary cracks that collect and leak gas. As a result, it is difficult for the coal seam sealing .
WhatsApp: +86 18838072829WEBJan 7, 2009 · A mathematical model was developed to predict the coal bed methane (CBM) production and carbon dioxide (CO 2) sequestration in a coal seam accounting for the coal seam model predictions showed that, for a CBM production and dewatering process, the pressure could be reduced from MPa to MPa and .
WhatsApp: +86 18838072829WEBAug 1, 2018 · The initial temperature of coal seam has a significant influence on gas extraction, the higher the initial temperature of the coal seam, the smaller the gas production rate is. This is because the gas drainage process is the joint action of coal seam damage, gas pressure, adsorption and desorption of gas, and temperature.
WhatsApp: +86 18838072829WEBJan 15, 2019 · One potential source of energy is extraction of unconventional gases, such as basincentered gas, tight gas, coal seam gas (CSG) and shale gas [1]. The extraction of natural gas from low permeability unconventional reservoirs requires methods to improve access to the reservoir. 'Hydraulic fracturing' is one such technique which has made gas ...
WhatsApp: +86 18838072829WEBMay 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 18838072829WEBFeb 13, 2020 · Coal seams, particularly deep unmineable coal reservoirs, are the most important geological desirable formations to store CO2 for mitigating the emissions of greenhouse gas. An advantage of this process is that a huge quantity of CO2 can be sequestrated and stored at relatively low pressure, which will reduce the amount of .
WhatsApp: +86 18838072829WEBMay 21, 2015 · By integrating coal production with gas extraction, coal seam gas becomes a useful resource. Advantage is taken of the effect of strata movement on gas pressurerelief and flow during the coal mining process to establish a single production system for simultaneous coal and gas extraction.
WhatsApp: +86 18838072829WEBMay 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 18838072829WEBBai, T, Chen, Z, Aminossadati, SM, Danesh, NN, Pan, Z, Liu, J Li, L 2016, Impact of flow regimes on coal fines generation during coal seam gas production process. in 50th Rock Mechanics/Geomechanics Symposium. 50th US Rock Mechanics / Geomechanics Symposium 2016, vol. 1, American Rock Mechanics Association (ARMA), pp. 356365, .
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