The order of coal seam mining for the similarity model was the #4, #5, and #6 coal seams ... As multiple mining is not currently occurring in the 1930 Coal Mine, examining the effect of gas extraction under mining of the #4 coal seam could also validate the experimental results. The strike length averaged 553 m, and the inclined …

Coal Mining and Processing Methods. T his appendix presents additional details on the individual processes that are involved in extraction of coal from surface and …

1 INTRODUCTION. With the gradual depletion of coal resources in eastern China, coal mining has been expanded in central and western regions, and thick coal seams are widely present therein. 1 At present, the maximum mining height reaches 8.8 m, and the geological conditions of large-mining height and a complex key layer are often …

The structure model of overlying strata in mining fields can be used to describe strata movement and predict mine disasters [1,2,3]; it is the foundation of safe mining in underground coal mines.The overburden structure theories and hypotheses proposed for mine pressure and rock strata control mainly include: key strata theory …

The parameters of pore-fracture structure and permeability have a controlling effect on the behaviors of gas adsorption/desorption and transportation in coal reservoir. A mathematic model for coal seams is of great significance to evaluate the mass migration within the coal fracture-matrix system. In this paper, the hydraulic-mechanical coupling model …

The pertinence and effectiveness of gas extraction for underground coal mining is an important issue for simultaneous exploitation of coal and gas. The key issue is the definition and analysis of mining-enhanced permeability of mining-induced fracture network. In order to describe the permeability evolution process during coal mining, the …

During coalbed methane (CBM) extraction and coal mining, the stress state, adsorption/desorption, and seepage behavior in coal will change significantly, …

@article{Xia2014AFC, title={A fully coupled coal deformation and compositional flow model for the control of the pre-mining coal seam gas extraction}, author={Tongqiang Xia and Fubao Zhou and Jishan Liu and Shengyong Hu and Yingke Liu}, journal={International Journal of Rock Mechanics and Mining Sciences}, …

Based on key strata theory in strata control, considering mining height and distance from the first sub-key strata to coal seam roof, mathematical model of dynamic evolution of mining fissure ...

Article. Quantification of Gas Transport Behavior During Coalbed Methane Extraction in A Coal Seam Considering a Dual-Porosity/Single-Permeability Model. …

In situ gas extraction is the main measure adopted by mines to achieve mining safety standards. Coal permeability is significantly influenced by coal shrinkage during gas release. Based on effective stress and additional damage that resulted from gas extraction, a unique model was proposed to describe the spatial and temporal …

BlackRock Mining Corporation's coal mining business model is designed to thrive in the post-2023 era, with a focus on starting operations and seeing results from 2024 onwards. This timing aligns with the ongoing global transition towards cleaner energy sources, allowing the company to cater to the demand for coal from power plants and ...

The study on the engineering scale showed the coal mining-affected area (approximately 70 m) along the mining direction of the Ji-14-31050 coal mining face with a depth of over 1000 m in the ...

7.2 Stress Evolution for Extraction of No. 9 Coal Seam. 1. The Three-Dimensional Stress Evolution. As pictured in Fig. 19, the stress peak value increases with coal seam mining, and the three-dimensional stress concentration phenomenon occurs at a distance of approximately 5 m from the working face. When the working face has …

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 double-pore double-permeability model; establishes a coupling model of the coal damage deformation field and matrix-fracture double diffusion seepage field; and …

The Liyazhuang Coal Mine is located on the southern edge of the Huozhou Coalfield in China's Shanxi Province (Fig. 1).The length of the coalfield (from west to east) is approximately 3.5 km, and its width from north to south is approximately 4 km, with total area measuring approximately 9.5 km 2.The Liyazhuang Coal Mine is identified as a …

In the "Code of Practice for Coal Mine Gas Extraction" (AQ1027-2006) and the "Basic Indicators for Coal Mine Gas Extraction" (AQ1026-2006) as well as other relevant codes, it is clearly stipulated that the gas concentration range must be controlled within 8 m 3 /t or that the coal seam gas pressure must be reduced to 0.74 MPa (gauge ...

Integrated coal production and gas extraction must be considered as a system which involves the exploration and measurement of stress field redistribution, deformation and …

Abstract. Gas drainage is the main technical measure to prevent and control coal and gas disasters. Reasonable extraction parameters can improve extraction efficiency and reduce the risk of gas accidents.

This study presents a sustainability evaluation model of geothermal resources in abandoned coal mine. In this model, the volume and spatial distribution of fractures were calculated based on the volume of the mined-out area and the strength of roof rock. Then, a dual porosity numerical model is developed to assess the potential of …

In the longwall mining method, mine development is carried out in such a manner that large blocks of coal, usually 100 to 300 metres wide and 1,000 to 3,000 metres long, are available for complete extraction (see …

face mining method used to extract coal in the United States and is the primary method used for coal valuation in the USGS surface-mining model. In this method, coal is exposed when overlying rock (called overburden) is stripped away leaving long, narrow, open trenches (also known as pits). The exposed coal is removed from the pit while ...

Fully coupled compositional (coal seam gas and air) model of coal deformation, coal gas flow and transport, and air flow in coal seams is developed to better understand the gas drainage processes and the coal gas–air mixing mechanisms during pre-mining coal seem gas extraction.The model was first verified by showing that the …

From Fig. 3, the mathematical model is observed to be quite for the evaluation of the gas extraction with slotted borehole.The gas-drained influence radius is closely related to properties of coal seam, such as the permeability, the CH 4 pressure, the temperature and the coal adsorption characteristics. In addition, the engineering tests …

Oct 2023. Xianzhong Li. Weilong Zhou. Shigang Hao. Jinhao Zhang. Request PDF | On Oct 1, 2023, Aitao Zhou and others published Coal mine gas migration model …

A remote sensing model to extract a coal area was developed by analysis of the features of the coal reflectance spectrum. The spectrum data of coal and other object samples from the Huolinhe (HLH ...

The gas–solid coupling model involving coal seam deformation, gas diffusion and seepage, gas adsorption and desorption was built and then imported into COMSOL Multiphysics to be solved, and the numerical simulation model is shown in Fig. 3.The length and height of the model are 250 m and 100 m, respectively.There is a protected coal …

face mining method used to extract coal in the United States and is the primary method used for coal valuation in the USGS surface-mining model. In this method, coal is …

The extraction of the gas enrichment area within the fracture of the coal seam roof by arranging boreholes or roadways can not only solve the problem of gas exceedance, but also further improve the utilization rate of CBM extraction. It will realize green, clean, and efficient utilization of CBM through highly recovered gas [21], [22], [23].

Coal exploration is a very demanding task, highly dependent on geological and economic factors and the utilization of coal. This lecture text includes information on a variety of geological techniques used in the exploration of coal and coal-bearing sequences, as well as on the calculation, assessment, classification, and reporting of …