1. Introduction. As the companion of coal seam, coal mine gas (CMG) is a major hazard source to coal mining practice. During the mining process, gas disasters such as gas explosion, gas combustion, and coal and gas outburst may occur, resulting in serious casualties and property losses. 1, 2 Especially when it enters deep mining, stress and gas pressure rise markedly, while permeability of the ...
WhatsApp: +86 18037808511National Partnership Agreement on Coal Seam Gas and Large Coal Mining Development (2012) Australian Government, Department of Agriculture, Water and the Environment. ... Matthai SK, Rathnaweera T, Zhang G (2019) Effect of coal maturity on CO 2based hydraulic fracturing process in coal seam gas reservoirs. Fuel 236:179189. Article Google ...
WhatsApp: +86 18037808511Integrated coal production and gas extraction must be considered as a system which involves the exploration and measurement of stress field redistribution, deformation and failure of coal and rock, gas pressure and permeability, and gas desorption and migration during the process of coal mining. Fundamental theory
WhatsApp: +86 18037808511Gas migration in mining disturbed coal seam (Liu et al., 2020). ... However, most current studies regard the diffusion process of gas in coal as a steadystate process, without considering time dependence of the diffusion process, resulting in a significant deviation between the model prediction results and the real experimental results. ...
WhatsApp: +86 18037808511Coal seam gas is a natural gas held in coal seams under pressure by groundwater. Coal seam gas wells release the gas by reducing the pressure through groundwater extraction. Extracted water and gas is diverted to surface infrastructure treatment and processing plants (Figure 1). The extracted water is termed 'coproduced water' (also ...
WhatsApp: +86 18037808511In drift mines, a tunnel is dug horizontally into the side of a mountain. In slope mines, this tunnel is diagonal. In shaft mines, elevators are used to move coal through vertical tunnels. Figure c : Subsurface mining involves digging tunnels to access coal deposits that are deep underground.
WhatsApp: +86 18037808511Based 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 18037808511This is particularly true in Australia, where both coal mining (Higginbotham et al., 2010) and coal seam gas developments (Luke et al., 2018) face widespread public opposition. Despite this public opposition, new coal mines and coal seam gas developments are still being approved by Federal and State Governments.
WhatsApp: +86 180378085111 Introduction. Recovery of coalbed methane (CBM) from coal seams can not only benefit mining safety, reduce greenhouse gas emissions, and also increase clean energy supply (Karacan et al., 2011; Moore, 2012).In the Junggar Basin, the CBM resources have been estimated at trillion cubic meters, which is the third largest CBM basin in China after the Qinshui Basin and Ordos Basin (Fu et al ...
WhatsApp: +86 18037808511When rockbursts and coal and gas outbursts simultaneously occur in a coal mine, changes in gas adsorption (concentration of ambient methane) and displacement of coal and rock must occur. The coassociated minerals in coal reservoirs can affect the mechanical properties and methane adsorption capacity, which are commonly disregarded. It is important to construct compound molecular structure ...
WhatsApp: +86 180378085111. Introduction. Coal mine gas disaster is always the most dangerous in the process of coal mining [1].The determination of coal seam gas content is one of the fundamental key works involving the regional prediction of coal and gas outburst, validity check of outburst prevention, prediction of coal mine gas emission and designing gas drainage systems [2], [3].
WhatsApp: +86 18037808511History Coalbed methane grew out of venting methane from coal seams. Some coal beds have long been known to be "gassy," and as a safety measure, boreholes were drilled into the seams from the surface, and the methane allowed to vent before mining.
WhatsApp: +86 18037808511THE IMPORTANCE OF COAL SEAM GAS IS CSG NEW? The potential of coal seam gas as an energy source has been recognised since coal mining started in Australia in the 1900s. Today, we have the technology and knowhow to extract it safely for use. CSG has been extracted safely in Queensland for around 20 years.
WhatsApp: +86 18037808511Coal Geology. Coal seams originate and are formed by the consolidation of biota, minerals, and natural chemicals through geologic time. Compression, heat, sedimentation, erosion, and chemical energy are agents of the coal formation process. Multiple coal seams can exist in a reserve, with each coal seam separated by sedimentary rock ...
WhatsApp: +86 18037808511Overview of emissions from coal mining and handling Methane (CH4) is produced during coalification (the process of coal formation). Only a fraction of this remains trapped under pressure in the coal seam and surrounding rock strata. This trapped methane is released during the mining process when the coal seam is fractured.
WhatsApp: +86 18037808511The process of gas extraction involves tapping into coal seams (layers of coal embedded in the earth) with the goal of extracting the methane gas trapped within. This gas is a byproduct of coal formation and is both pure and nontoxic, making it a commercially attractive energy resource. The location of conventional and unconventional gas.
WhatsApp: +86 18037808511Coal is a critical natural resource in the world, which provides large amounts of energy and raw materials for meeting industrial demands in China, America, India, Indonesia, etc. [1,2].With mining depth becoming larger, the dynamic hazards induced by gas and mining disturbance are raised, especially coal and gas outburst [].The coal and gas outburst hazards always occur in mining during the ...
WhatsApp: +86 18037808511The nation's coal mines are major emitters of methane, and that is complicating global talks on reducing this potent greenhouse gas. By Christian Shepherd. December 1, 2023 at 5:00 EST ...
WhatsApp: +86 18037808511Practice, statistical data and experiments of outburstprone coal seam mining have proven that coal and gas outbursts are the result of the comprehensive action of the in situ stress (gas pressure ...
WhatsApp: +86 18037808511Their value to potential research is found in the proximate analyses that indicate key characteristics of coal. The characteristics evaluated in these reports included: the ash yield, or the incombustible material in coal; fixed carbon, the amount of carbon that remains in coal after combustion occurs; moisture, how much moisture content was ...
WhatsApp: +86 18037808511Most coal mines in China are opting for deep mining due to the rapid reduction of shallow coal reserves, which increases the risk of waterinrush accidents. Given the limitation of waterinrush coefficient method in evaluating the risk of water inrush from the coal seam floor, we analyzed the permeability resistance of the floor under different lithology combinations, and structural conditions ...
WhatsApp: +86 18037808511Coalbed 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 manifold benefits, extensive investigations have been conducted on methane emissions ...
WhatsApp: +86 18037808511However, in the current process of coal mining, coal mine disasters occur frequently, and the level of coal mine safety control and management is still very insufficient. ... high cost and low efficiency in the process of indirect determination of coal seam gas content, the basic gas parameters and coal quality indexes of 24 coal samples from 5 ...
WhatsApp: +86 18037808511Coal seam gas formation. During coalification, large quantities of methane are generated. This gas is adsorbed onto the coal surface in cleats and pores, and is held in place by reservoir and water pressure. Coal rank, reservoir pressure (related in part to depth) and temperature are important factors controlling the amount of methane held in a ...
WhatsApp: +86 18037808511The comining of coal and gas is the inevitable future direction of the mining of coal resources. Taking coal mining and gas extraction as the two subsystems of the coal and gas comining system, to reveal the mechanism of action between coal mining and gas extraction is the premise of orderly comining.
WhatsApp: +86 18037808511Coal seam water injection is vital in mitigating dust pollution in coal mining operations. To investigate water imbibition and adsorption behavior on the coal surface following injection into coal seams, as well as the impact of surfactants, coal particles with sizes of 68 mm, 35 mm, and mm were selected from the Dongtan Coal Mine in Shandong Province, China.
WhatsApp: +86 18037808511And both coal seam gas and shale gas produce about half the CO₂ of brown coal. In North America today, about 2025% of the total gas consumed comes from shale gas deposits.
WhatsApp: +86 18037808511Owing to the exhaustion of shallow coal resources, deep mining has been occupied in coal mines. Deep buried coal seams are featured by the great ground stress, high gas pressure, and low permeability, which boost the risk of gas disasters and thus dramatically threaten the security about coal mines. Coal seam gas pressure and gas content can be decreased by gas extraction, which is the primary ...
WhatsApp: +86 18037808511The integrated mining machinery coordinates with each other to realize the whole process of coal mining, including coal cutting and transportation, dust capturing, roof supporting, and other operations. ... In the longwall panel scale, the prepumping is mainly adopted to extract and control coal seam gas . The construction crafts of gas ...
WhatsApp: +86 18037808511Each link of the coal mining process will produce corresponding carbon emissions, so the carbon emissions of each link should be measured comprehensively. ... Xiaocun C, Hui T (2018) Technical scheme and application of pressurerelief gas extraction in multicoal seam mining region. Int J Min Sci Technol 28(3):483489. Article Google Scholar
WhatsApp: +86 18037808511From this, the primary equipment and key production technologies were determined for the proposed softrock protective seam mining. Finally, in combination with the optimal arrangement of the working face, the pressurerelief gas extraction technology accomplished the pressurerelief mining of the protected coal seam. 2.
WhatsApp: +86 18037808511The widely spread CarboniferousPermian coal seam group in southern China has great potential for coalbed methane resources, but the extensively developed tectonically deformed coal seriously restricts its development. Taking the Dahebian block in western Guizhou as the study area, the geological model of coalbed methane reservoirs in the tectonically deformed coal seam group was established ...
WhatsApp: +86 18037808511The study further unraveled the development process of overburden fracture across the entire life cycle of the coal seam mining process and investigated the law of pressure relief gas migration in the mining fracture field. ... The construction of the coal seam gas power station site was shown in Fig. 17. Download : Download highres image ...
WhatsApp: +86 18037808511Coalbed methane (CBM), is also known as coalbed gas and coal seam gas/methane (CSG/CSM), which are terms referring to the unconventional natural gas resource stored in coal beds and are expected to be an important energy resource of global significance in the future (Rightmire 1984; Rice 1993; Flores 1998, 2013; Palmer 2010; Yang and Liu 2021). ...
WhatsApp: +86 18037808511Coal seam groups are widely distributed in mining areas of different regions in China, especially closely spaced coal seam groups (Wang et al. 2013).Selecting a coal seam with the optimal reliability factor as the first mining seam is necessary to achieve safe and highefficiency mining due to the diversified conditions of coal seams during mining (Wang et al. 2017; Li et al. 2021; Wu et al ...
WhatsApp: +86 18037808511