The occurrence and mining conditions of underground coal seams become more complex with increasing mining depth, making mining gas extraction more and more problematic (Chen et al. 2020; Wang et al. 2021a, b).Gas extraction efficiency directly depends on the coal seam permeability, which, in turn, is controlled by several internal factors (such as coal strength, stress loadingunloading ...
After decades of stagnation, the Tar Heel State is the beneficiary of a lithium rush fueled by demand for car batteries. Albermarle, the world's largest lithium producer, is trying to restart a ...
After years of development, paste backfill technology has become an important part of China's green safety mine construction and coal green mining technology system in the new era. In this paper, the research status of paste backfill technology in China's coal mines is expounded from the aspects of paste backfill materials, strata control theory, and paste backfill technological process ...
Mining Terms. A machine, usually used in coal, that will cut a 10 to 15cm slot. The slot allows room for expansion of the broken coal. Also applies to the man who operates the machine and to workers engaged in the cutting of coal by pick or drill. A system of mining in more than one working place at a time, that is, a miner takes a lift ...
The land which was used to obtain these resources must be rehabilitated as much as possible. The objectives of this process include: minimizing environmental effects. ensuring public health and safety. preserving water quality. establishing new landforms and vegetation. removing waste and hazardous material. stabilizing land to protect against ...
As one of the most dangerous disasters in underground coal mines, water inrush is commonly encountered in the process of tunnel excavation and mining working face advancing (Bagci et al. 2014; Wu et al. 2011a).Once water inrush occurs, groundwater rapidly flows through rock fissure and enters the mining space from the aquifer under the action of water pressure.
The gas phase flow in coal mining face is regarded as the adiabatic fluid flow of the constant incompressible viscosity. The governing equations of the gas phase flow can adopt the unsteady NavierStokes equation, and the turbulent flow can be expressed by the standard k − ε model (Scungio et al., 2018; Yang et al., 2019).
The primary coal is generally viewed as a dualporosity medium composed of coal matrices and fractures, and can be described by the cube model shown in Fig. 1 (a). 31, 32, 33 For underground mining, coal seam is often disturbed by mining process or reservoir stimulation. 34, 35 These processes often create new fractures which cut the primary matrix into smaller ones.
COAL MINING METHODS Surface Mining In surface mining, the ground covering the coal seam (the overburden) is first removed to expose the coal seam for extraction.
Life cycle assessment (LCA) was used to quantify carbon emissions in whole process of coal mining, including mining, ventilation, drainage, power consumption, transportation, and postmining activities. ... Stage of gaswater twophase flow. When the pressure of the coal seam decreases, the methane in the matrix pores of the local reservoir ...
• the process of longwall mining for use in underground mines; • the coking process, transforming coal into coke, in beehive ovens; • the blast furnace iron making process and the use of coal in the furnace; • the use of coal in the creation of electricity; • the use of coal in the production of a variety of products such as
Coal mining from 1999 to 2010 accounted for a runoff reduction of × 10 8 m 3. Guo et al.(2019) Kuye river basin: MWBM: ... The appearance of goaf changed the original water balance process, and the underground water flow needs to be considered as the output of the system. By introducing the goaf water balance equation and parameter X ...
Resource Demands of Coal Production. In Environmental Impacts of Coal Mining Utilization, 1987. A Waterconscious Future. Having estimated the quantity and location of future coal production and processing, and the methods by which this coal will be extracted, transported and processed, Alcamo (1984) computed the industry's water requirements. He assumed a "waterconscious" future in ...
At present, the first coal seam in the western mining area has been exhausted, and the mine is gradually mining the lower coal seam 9. During the mining process of shallowburied and close ...
PDF. Size: MB. Download Now. Managing the logistics workflow starts first in getting a detailed picture of the entire system. Plus, getting a document such as this is easy when you have a chart in google docs. So grab this template now and gather critical ideas on how the step by step process needs plotting out. 5.
In coal mine paste filling technology, geomaterials like coal gangue and fly ash are used as the main component, and cement is applied as the cementing material. In the mining production, miningandfilling is a cyclic work, where the filling immediately after mining and mining immediately after filling. Long solidification time after filling will affect mining; consequently, the paste should ...
Mining Process and SAP Solution. 1. Mining industry Overview. The industrial production and economic growth drives the demand both in domestic and foreign markets. High capital costs involved in the mining industry makes it vulnerable to ponder upon the volatility. The dip in the china's growth rate has made the key commodities like iron ore ...
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Highwall mining is an adaptation of auger mining. Instead of an auger hole, an entry into the coal seam is made by a continuous miner, remotely operated from a cabin at the surface. The cut coal is transported by conveyors behind the miner to the outside. Using a television camera, the operator can see and control the miner's progress.
Coal Gasification. Nicola J. Wagner, ... van Dyk, in Applied Coal Petrology, 2008 Publisher Summary. This chapter deals with coal gasification, which is a process that converts carbonaceous materials, such as coal, petroleum, petroleum coke, or biomass, into carbon monoxide and gasification as a powergeneration technology is gaining popularity due to the ready global ...
Unsteady creep of coal seams and the resultant abnormal flow of coal seam gas are the main reasons for dynamic disasters in deep mines. In this study, for investigating the evolution of gas depletion in deep mines, the flow field evolutions during gas adsorption and desorption were simulated first based a multifield (coal deformation field, diffusion field and seepage field) coupling model ...
A flowchart of the process and outcome of the literature search is provided in Figure S1. NoteExpress was used to screen and manage literature and delete duplicate literature. ... Given the feedback of soil and water conservation to the coal mining process upon spatiotemporal characteristics response, the higher sensitivity of runoff to mining ...
Firstly, the process flow of the solid backfilling operation is more complicated in the back, and the spatiotemporal linkage (SPL) between actions of the cylinders powering each support and between hydraulic supports in the whole face lacks continuity.
The research results can provide important references for the stability of deep underground projects such as coal mining process, tunnel excavation process, nuclear waste storage and other engineering stability. ... Predrilled coal's initial flow rates perpendicular to bedding planes and parallel to butt cleats directions were only % and ...
Gas preextraction technology in a coal reservoir can not only reduce greenhouse gas (GHG) emissions but also effectively recover coalbed methane (CBM). In this work, we use a geomechanicalcoupled gas flow (GCF) model to simulate and analyze the preextraction effect of a miningdisturbed coal seam. First, the simulation results of the GCF model are compared with field test data to verify the ...
Development of bamboo biodiversity on mining degraded lands: A sustainable solution for climate change mitigation. Lal Singh, ... T. Mohan Manu, in Phytorestoration of Abandoned Mining and Oil Drilling Sites, 2021 Impacts of mining activities on environment and climate change. Opencast mining operations involve the removal of huge quantities of overburden, dumping, and backfilling of the ...
The specific process of this mining process system is as follows: a singlebucket excavator loads the coal in the stope to the truck to complete the mining and loading operation, and the truck transports coal to the designated semifixed crushing station according to the dispatch instruction to complete the transportation operation.
Openpit mining. Some 53% of South Africa's coal is produced from surface mining, via opencast or openpit mines. This is because the coal is less than 60 metres below the surface. Openpit mines use draglines, as well as truck and shovel operations to extract coal. A dragline excavator uses a dragline to pull a bucket by a wire cable.
Process flow diagram of the gangue crushing system. ... Filling mining process. The coal seam in the working face was stable, with an average thickness of m. The design adopted a singlestrike longwall comprehensive mechanized filling mining method, with backward mining in the area, and a filling method to deal with the goaf. ...
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