Surface-Mining Modeling for USGS Coal Assessments
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 …
Optimization of Accurate Spacing for Gas Extraction from …
As the main means of gas disaster prevention and control in deep mines, coal seam gas extraction technology can reduce environmental pollution while reducing …
Coal mining
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 …
Coupling between Damage Evolution and Permeability Model …
During coalbed methane (CBM) extraction and coal mining, the stress state, adsorption/desorption, and seepage behavior in coal will change significantly, which is the principal cause of the outburst accidents. Therefore, it was considered particularly important to investigate permeability behavior under damage conditions. In this paper, to simulate …
Coal mine gas migration model establishment and gas …
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.
Coal Mining Business: What, Why, Who, When, Where, How
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 ...
Dynamic evolution of mining fissure elliptic paraboloid zone …
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 ...
Surface-Mining Modeling for USGS Coal Assessments
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 ...
The effects of key rock layer fracturing on gas extraction during coal
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 …
Gas extraction of coal seam roof fractured zone in China: A …
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].
Numerical Investigation of the Dynamic Mechanical State of a Coal
In this study, based on the geological condition of a typical longwall panel from the Tangshan coal mine in the City of Tangshan, China, a numerical fast Lagrangian analysis of continua in three dimensions (FLAC 3D) model was created to understand the dynamic mechanical state of a coal pillar during longwall panel extraction. In this study, …
Effect of protective coal seam mining and gas extraction on …
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 …
A fully coupled coal deformation and compositional flow model …
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 …
A new approach modeling permeability of mining-disturbed coal …
In this model, the coal is viewed as a dual-porosity medium and is consisted of coal matrix and fractures as illustrated in Fig. 2. ... A fully coupled coal deformation and compositional flow model for the control of the pre-mining coal seam gas extraction. International Journal of Rock Mechanics and Mining Sciences, Volume 72, 2014, pp. …
Coal permeability model on the effect of gas extraction …
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 …
Coal mine gas migration model establishment and gas …
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 …
Characteristics of Mining-Induced Fractures Under Inclined Coal …
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
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 …
Coal: exploration, reserves, and utilization | ChemTexts
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 …
Coal Mining KPIs: Track & Calculate
Let's consider an example to better understand how to calculate the cost per ton of coal extraction. If a coal mining company incurs a total mining cost of $10,000 and extracts a total of 2,000 tons of coal, the calculation would be as follows: ... Coal Mining Financial Model $169.00 $99.00. Get Template. Expert-built startup financial model ...
Modeling and experimental study on methane diffusivity in coal …
Therefore, coal mines generally extract gas through a combination of combined extraction technology of ground wells and underground boreholes to ensure the safety of coal mining and achieve the utilization of CBM energy [4], [5]. However, with the depletion of shallow coal resources and a gradual increase in the depth of coal mining, …
Coal mine gas migration model establishment and gas extraction …
The coupled model is verified by theoretical analysis and against observations from a coal and gas outburst incident comprising 2887 tonnes of coal that occurred in the Jiulishan coal mine, China ...
Fully coupled thermo-hydro-mechanical model for extraction of coal …
To simplify the calculations, the schematic model of the gas extraction in the M8 coal seam with a slotted borehole is shown in Fig. 3. The calculation model is 20 m long and 2 m high. ... A fully coupled coal deformation and compositional flow model for the control of the pre-mining coal seam gas extraction. Int. J. Rock Mech. Min. Sci., 72 ...
Land subsidence calculation model under the coupling …
Land subsidence has become a widespread engineering geological problem due to human-induced causes such as the withdrawal of groundwater and the extraction of coal and ores. There is a relative lack of research on land subsidence under the coupling effect of groundwater and coal mining. This paper uses numerical and theoretical …
Minerals | Free Full-Text | Study on a High-Efficiency Mining …
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 ...
An open database on global coal and metal mine production
Our open database on global coal and metal mine production 12 covers worldwide mining activities of metal ores and coal, on an individual mine level. It comprises 1171 mines, production data for ...
Image feature extraction and recognition model construction of coal …
Aiming at the problem of low accuracy of coal gangue recognition in fully mechanized caving mining, the extraction method of Coal and gangue images features is proposed, and the corresponding coal ...
Coupling between Damage Evolution and Permeability Model …
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 ...
Optimization of Accurate Spacing for Gas Extraction from Damaged Coal
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 …
Thermo-hydro-mechanical coupled mathematical model …
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 …