قائمة الطعام
Introduction. Gas disaster is a main inducement to affect the safety of coal mines, especially methane (CH 4) explosion and hydrogen sulfide (H 2 S) poisoning. CH 4 is a kind of highly flammable gas with an explosion limit ranged from 4.9% to 15.4% (volume ratio), respectively [1], [2]. Accordingly, H 2 S is a trace component in coal mine gas, …
Figure 2 shows a view of the face fill for solid backfill mining. This includes hydraulic support, scraper conveyors, throwing machines and their supporting equipment systems. The hydraulic ...
To further examine the labor market consequences of coal, Table 3 reports results for models where the 2000 and 2010 ratios of the disabled to total employed are the dependent variables. Certainly coal mining (especially underground mining) is a dangerous vocation with consequences such as black lung disease that can spur …
Coal is anticipated to maintain a dominant role in China's energy system for an extended period (Xie et al., 2019).Meanwhile, the process of coal mining necessitates a substantial amount of water for various purposes, including dust control, cooling, domestic use, and other applications (Liu et al., 2022, Pan et al., 2012).However, coal and water …
The overall coal mining process consists of several sequential stages: (1) exploration of a potentially economic coal seam to assess minable reserves, environmental issues, …
The accuracy of the prediction model increases with the increasing number of spectral variable dimensions (in the following order: 1DV < 2DI < 3DI). This study proves that the 3DI is the first choice for the optimal band combination algorithm to derive sensitive parameters related to SOM in the coal mining area.
With the increase of mining depth in Chinese coal mines, the entry floor heave becomes one of the major engineering problems. This paper has studied the stress and displacement distribution around an entry in Buertai coal mine, China. The mechanism of floor heave is analyzed using the method of complex variable function. The …
The operation optimization problem of this system is characterized by multi-scenario, multi-variable, multi-objective, and strong constraints, making it difficult to be solved. ... such as mine wastewater, can significantly reduce their operation costs. Integrated coal mine energy systems (ICMESs), typical examples of integrated regional …
This article reviews evidence for the public health impacts of coal across the extraction, processing, use, and waste disposal continuum. Surface coal mining and processing impose public health risks on residential communities through air and water pollution. Burning coal in power plants emits more nitrogen oxides, sulfur dioxide, particulate …
A linear relationship between the effect size of target variables and the influence factors was observed, which indicates that soil and water conservation …
Coal mining: Risk-taking is predicted by (a) perceived time pressure linked to productivity, (b) social influence within work teams, (c) the perception that management prioritizes productivity, and (d) perceived lack of ability to control and manage risk. Paul and Maiti (2007) India: Underground coal mining
Coal is a non-clastic sedimentary rock.They are the fossilized remains of plants and are in flammable black and brownish-black tones. Its main element is carbon, but it can also contain different elements such as hydrogen, sulfur and oxygen. Unlike coal minerals, it does not have a fixed chemical composition and crystal structure.Depending …
Generally, mining approaches for thick coal seams include top-coal caving mining, multi-slicing mining, and full-height mining techniques, which involve a similar abutment stress distribution to conventional mining methods for ordinary coal seams; however, the stress evolution trend has a larger scope of influence and a higher …
07 March 2023. Introduction. The pollution caused by coal dust has both direct and indirect effects on the environment, but research initiatives have given innovation …
coal mining, extraction of coal deposits from the surface of Earth and from underground. Mongolia: coal mine.
Notably, while there has been a decline in major accidents and fatalities since the enhancement of outburst prevention measures in 2009, accident rates and fatalities associated with coal mining remain somewhat variable(C. Zhang et al., 2021a), as shown in Fig. 1. Thus, the emphasis on preventing outbursts remains paramount, even amidst …
The BaiYinhua coalfield extends approximately 60 km from the northeast to the southwest of the watershed, with an average width of 8.5 km, encompassing a total mining area of about 510 km 2, representing approximately 12% of the watershed.The coal-burial depth gradually increases from the southeast to the northwest, and the total …
In the comprehensive evaluation of coal mine safety, the indices in the hierarchical structure are often expressed as uncertain random variables. Therefore, a new assessment approach based on ...
Combined with the research results of Chen et al. 49, it is feasible to apply relevant variables to the field of coal mine safety, and the research results have certain similarities. Medical ...
1. Introduction. Despite international efforts dedicated to phasing out fossil fuels [1], [2], 4 coal accounted for over one-third of global electricity generation in 2021, raising associated carbon dioxide (CO 2) emissions to record levels [3]. 5 Moreover, and further counteracting climate change mitigation scenarios [4], [5], [6], 40 % of the growth …
Institute of Economic Growth Delhi- 11007. Abstract. Production of coal from opencast and underground mines involves different mix of technological, capital, labour, energy and material input configurations. Planning and. designing of coal mine operations depend partly on these input characteristics and partly on scale factors which are based ...
1. Introduction. As China's major energy supply, coal plays a crucial role in sustaining the country's energy requirements (Burgherr and Hirschberg, 2007, Wang et al., 2014), offering up to 70% of the country's energy supply over the past six decades (Geng and Saleh, 2015, He and Song, 2012).China is the largest country both in coal …
Mining, minerals, and metals are important to the economic and social development as they are essentials for modern living. However, supplies of minerals, such as coal, are limited, and sustainable management of natural resources requires the maintenance, rational and enhanced use, as well as a balanced consideration of …
Section snippets Preliminaries. Let Γ be a nonempty set, L be a σ-algebra over Γ, and M be a uncertain measure on L.Each element Λ in L is called an event, and M {Λ} indicates the possibility of event Λ occurring.. Definition 1 Liu, 2013. An uncertain random variable is a function ξ(ω) from a probability space (Ω, A, Pr) to the set of …
In coal price, coal mining companies are companies with world-class commodities so that their characteristics are strongly influenced by movements in global commodity prices that have been ...
Areas with a legacy of coal mining are very familiar with the damaging effects of surface subsidence. Subsidence can cause damage to utilities (e.g. Holla, 1988), structures, water bodies (Booth, 2002a, Booth, 2002b, and Dumpleton, 2002), and agricultural land (Darmody et al., 1989).Surface subsidence is caused by the eventual …
, Mark D. Partridge d., Michael Farren b., Linda Lobao c. Show more. Add to Mendeley. https://doi/10.1016/j.eneco.2015.04.005 Get rights and content. …
Based on the questionnaire survey and analysis of front-line employees of two coal mines in China, a model of the relationship between workload, job satisfaction …
In longwall mining, one of the factors most influencing safety in underground coal mining is the stress change, especially when such work is carried out within the thickness variation of a coal seam. This paper analyses the special case of a coal seam which suffers significant overstress as a result of variations in the geometry and …
The environmental challenges from coal mining include coal mine accidents, land subsidence, damage to the water environment, mining waste disposal and air pollution. These are either environmental pollution or landscape change. A conceptual framework for solving mine environmental issues is proposed. Clean processes, or …
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