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The proximate contents of the OCD samples were measured based on the China National Standard, GB/T 212–2008. The coal samples from the underground mining sites were sampled along with the OCD samples, following GB/T 482–2008, and their maximum vitrinite reflectance values (R o) were measured following GB/T 6948–2008; …
Abstract. Moisture is one of the most important factors that influences coal seepage and coal-bed methane (CBM) extraction. To obtain the water occurrence state and dynamic processes of water change in coal, a series of microscopic observation experiments of …
Soil moisture is a critical parameter for land reclamation and ecological restoration in mining subsidence areas. However, limited research has been conducted into the impact of subsidence on soil moisture in semi-arid areas. In this study, the subsidence and soil moisture of four coal seams (4101 and 4102 coal seams are 2-year and 1 …
Excessive coal moisture leads to a lower heating value and power plant efficiency, and increased transportation costs. Therefore, coal stockpile management and moisture control are particularly important in …
There are four major types (or "ranks") of coal. Rank refers to steps in a slow, natural process called "coalification," during which buried plant matter changes into an ever denser, drier, more carbon-rich, and harder material. The four ranks are: Anthracite: The highest rank of coal. It is a hard, brittle, and black lustrous coal, often referred to as hard coal, …
Stone dusters are required for all Australian underground mines. They spray stone dust to encapsulate coal dust, preventing explosions. CR's Razer stone dusting systems have been relied on for years by top tier miners. Our stone dusters just work, with minimal moving parts or breakdown issues, even in the harshest underground environments.
Soil water content is an important variable in hydrology and many related disciplines. It affects runoff from precipitation, groundwater recharge, and evapotranspiration.
As the depth of coal seam mining increases, coal and gas outburst prevention and control face unprecedented challenges. In recent years, freezing …
Coal seam mining causes fracture and movement of overlying strata in goaf, and endangers the safety of surface structures and underground pipelines. Based on the engineering geological conditions ...
reliable and sensitive to soil moisture in the whole coal mining zone of Northern Shaanxi based upon the soil sample parameters collected from in situ site investigation, spectral data gathered simultaneously and the images of Landsat7 ETM. The model uses different phases of Landsat data to retrieve soil moisture and analyze the patterns of ...
Prompt : Caesar is a famous mining equipment manufacturer well-known both at home and abroad, major in producing stone crushing equipment, mineral separation equipment, limestone grinding equipment, etc.
The coal development zone of Northern Shaanxi, China is one of the eight largest coal mines in the world, also the national energy and chemical bases. However, the coal mining leads to ground surface deformation and previous studies show that in collapse fissure zone soil water losses almost 50% compared with non-fissure zone. The main objective of this …
Pyrite has a significant effect on the spontaneous combustion of coal. The presence of pyrite can change the propensity of coal towards spontaneous combustion. The influences of various pyrite contents on the parameters of spontaneous combustion, such as index gases, temperature and released heat etc., were investigated in this study. Coal …
Soil porosity and moisture are critical indicators of soil quality. In coal–grain intercropping areas, centuries of coal industry activities have resulted in coal particle contamination, …
Coal rank is defined by several parameters throughout the rank range, from heating value and moisture in lower rank coal (lignite and subbituminous), to volatile matter/fixed carbon and total carbon (proximate and ultimate analyses) in high and medium volatile bituminous rank coal through, at least, semi-anthracite, and hydrogen and X-ray ...
Request PDF | Experimental study on the effect of inherent moisture on hard coal adsorption–desorption characteristics | Coal is a complex geological body that is composed of organic material ...
Coal is a black or brownish-black sedimentary rock that can be burned for fuel and used to generate electricity.It is composed mostly of carbon and hydrocarbons, which contain energy that can be released through combustion (burning). Coal is the largest source of energy for generating electricity in the world, and the most abundant fossil fuel …
The current study investigated the impact of coal mining on deep soil moisture from the perspective of the absolute value of soil moisture. A combined …
moisture range of long-flame coal is 3–12%, whereas the moisture in anthracite is lower (Tang et al. 2015; Wang et al. 2014a; Yu and Cheng 2012). The presence of different inherent moistures will occupy the gas adsorption sites of coal and the channel of gas migration and diffusion, which determines the coal gas content and outburst risk (Beam-
Mining. In Australia, nearly 80% of coal is produced from open-cut mines, in contrast to the rest of the world where open-cut mining only accounts for 40% of coal production. Open-cut mining is possible because coal seams are close to the surface. Such mining is cheaper than underground mining and enables up to 90% recovery of …
the impact of coal mining on the moisture movement in a vadose zone in open-pit mine. Sustainability 2021, 13, 4125 3 of 16 areas. Field investigation, laboratory tests, and numerical simulations ...
The study results can serve as the baseline for monitoring environmental impacts on soil moisture in the regions due to coal mining. Discover the world's research. 25+ million members;
This study revealed the principles of spatial variability of soil moisture in coal mining subsidence areas in Northwest China, which can provide a scientific basis for the restoration of mining areas.
Furthermore, this region is the biggest coal mining base in China with about 60% of China's coal storage (Tian et al., 2008), and coal mining activities have caused serious damage to the ...
The reduced heating value is caused by increased moisture and ash in the coal. At Coal Creek, the plant design fuel had a moisture content of about 36.6 percent and an ash content of 6.2 percent ...
Soil water content is an important variable in hydrology and many related disciplines. It affects runoff from precipitation, groundwater recharge, and evapotranspiration. This research used the coal mining area of the Changhe River Basin in the Loess Plateau as a study and using SAR (Synthetic Aperture Radar) data, the …
(sandy sediments would later become obstructions to the coal-mining process). After the peat was buried, the coal-forming process, called coalifi cation, began. ... lignite is changed into subbituminous coal. Subbituminous coal has a moisture content less than that of lignite, and a heating value that ranges from 8,300 to 11,500 Btus. Subbitumi-
value (CV), ash, moisture, sulphur (). Fig.1 ... Open-pit coal mining is widespread in Ethiopia where there are more than 430 million tons of coal deposits found in the country of ...
The changes of the spatial distribution of inversed soil moisture revealed that the trend of soil moisture contents of the study area was in general being gradually reduced from …
These "Beehive" coke ovens were constructed in the late 1890's to carbonize or "Coke" coal mined in coal basin for the Colorado Fuel and Iron company. A narrow-gauge railroad, approximately 12 miles long …
containing coal under the same moisture conditions is compared and analyzed. 2.2. Coal Sample Preparation. Coal and gas outburst phenomena often occur during the process of coal mining via the method of "stone gate coal uncovering" and in geological structural zones, and there is a more obvious outburst risk in soft