This study investigates multiple types of water resources in the western mining area in China, their supply-demand balance by using the same dimension gray recurrence dynamic model GM (1, 1), and water content coefficients of mines to ease water supply-demand contradiction. A …

Background Selection of a suitable mining method for extraction of a thick coal seam with optimal recovery and safety is an extremely delicate process. In fact, single lift working of full thickness of a thick coal seam has always a verge over the multi-slice working due to favorable economics and high production and productivity. Blasting Gallery (BG) method is suitable for …

The Journal of the Southern African Institution of Mining and Metallurgy ... "In order to reach the goal of optimal and safe extraction of the mineral reserve, the mining industry is increasingly focusing on reconciliation across the mining value chain to ensure that the mining process occurs in a progressively more predictable manner ...

12%The accurate acquisition of information concerning farmland in coal mining areas with high groundwater levels can provide a basis for land dynamic monitoring and protection. In this study, visible light images from an unmanned aerial vehicle (UAV) were used as the data source, from which farmland located in the coal mining areas with high groundwater levels were …

1. Introduction. Coal gangue is an industrial solid waste produced by coal mining and processing [1–3].The average production of gangue accounts for 10–15% of raw coal production [4,5], making coal gangue one of the biggest solid wastes in China.At present, utilization ratio of coal gangue can reach about 60% in some countries.

optimal extraction for coal mining jurnal. Mining - Wikipedia, the free encyclopedia.Mining is the extraction of valuable minerals or other geological materials from the earth from an orebody, lode, vein ...

coal extraction operation through the basic mining equations. Conduct a basic cost evaluation for each improved KPI based on benchmarking and industry standards. A literature review was conducted to gain understanding of the background of the project as well as to limit the context to the milieu of the investigation. In addition, the literature

It is applied in numerous coal and quarry mining operations around the world. The broad objective of this research was to improve current surface mining practices and reduce negative environmental impact of overburden removal in WV. The specific objectives were to (i) compare conventional sur-face mining method (drilling, blasting, digging ...

Downloadable (with restrictions)! Several articles have confirmed the social and environmental consequences of opencast coal mining. The main purpose of this study is to simulate the optimal extraction policy of coal mining with and without the internalization of the environmental and social monetary costs that occur in the Mining District (located in the central part of the Department of El ...

underground coal pillar extraction. International Journal of Rock Mechanics and Mining Sciences,48(5): 794-804 P. Konicek, K. Soucek, L. Stas and R. Singh, 2013. Long-hole de-stress blasting for rock-burst control during deep underground coal mining.International Journal of Rock Mechanics & Mining Sciences, 61(2013): 141–153.

(2016) Optimal extraction policy when the environmental and social costs of the opencast coal mining activity are internalized: Mining District of the Department of El Cesar (Colombia) case study. Energy Economics 59, 159-166.

@misc{etde_20386705, title = {Green technique in coal mining} author = {Qian, M, Xu, J, and Miao, X} abstractNote = {The concept of green technique in coal mining was proposed. Its connotation and technical system were explained. The theory of the green technique in coal mining is the distribution behaviour of joints, fractures and bed separations, and the seepage flow behaviour of …

Another important point for optimal coal extraction at shallow covers is competency ... T. N. (1999): W ide stall mining for optimal recovery of coal from a multisection. developed thick seam ...

The annual coal mining production data from 1870 to 1931 was acquired from the United States Geological Survey (USGS) and the Bureau of Mines Mineral Resources of the United States documents (USGS 1882–1931). These documents were published from 1882 to 1931 and contain annual county-level coal mining production information.

Owing to the low coal permeability coefficients and poor gas extraction efficiencies associated with the extraction of coal in the Huainan coal mining area, the aim of this study was to design, for the first time, a high-pressure low-temperature liquid CO 2 (LCO 2) pump for engineering tests with respect to the fracturing of coal seams and the improvement of CH 4 recovery in China.

Most coal mines in China are currently mining close coal seams. Roadways in close coal seams, especially ultra-close coal seams, confronted difficulties in maintaining, including large deformation of the roadway, roof caving, rib spalling and floor heaving. This is mainly caused by the complicated stress and geological conditions, shattered roof, improper layout and support.

Coal mine methane (CMM) is a term given to the methane gas produced or emitted in association with coal mining activities either from the coal seam itself or from other gassy formations underground. The amount of CMM generated at a specific operation depends on the productivity of the coal mine, the gassiness of the coal

the optimal conditions, which is the major reason for high alumina extraction rates. 1. Introduction Coal gangue is an industrial solid waste produced by coal mining and processing [1–3]. The average production of gangue accounts for 10–15% of raw coal production [4,5], making coal gangue one of the biggest solid wastes in China.

2.1 Reasons Affecting Production of Coal Despite of installation and use of modern technology in open cast coal mining, the coal extraction and production falls far behind as compared to the global standards. Indian coal industries have experienced a wave of …

The scope for optimal recovery of coal locked in oversize pillars of VII/VIII seam led to the trial of wide stall mining at this colliery. The 17 m thick VII/VIII seam was fully developed in two sections: 3.0 m thick bottom section along the floor and a 2.4 m top section, leaving 6.4 m coal parting between the two sections and 5.0 m coal in the roof.

Assuming in the perfectly competitive market, using the optimal control theory and making the social welfare as the maximization target, the paper studies on environment cost which impacts the optimal extraction path of exhaustible resource. The special case result shows that: the time of optimal exhaustion increases with the addition of marginal environmental cost, the price has negative ...

Jorge Andrés Perdomo Calvo, Ana María Jaramillo Pérez Optimal extraction policy when the environmental and social costs of the opencast coal mining activity are internalized: Mining District of the Department of El Cesar (Colombia) case study, Energy Economics 59 (Sep 2016): 159–166.

Coal mining is a capital intensive, high volume ... operations to ensure the optimal overall extraction of coal reserves. Mine planning is ... The Journal of The Southern African Institute of Mining and Metallurgy VOLUME 110 NON-REFEREED PAPER MAY 2010 241 ...

pre‐extraction time during the mining of coal seams are considered as the most important parameters for gas pre‐ extraction in coal seams undermining conditions.5,11 The borehole spacing and the borehole layout during gas pre‐ extraction are both related to …

Jorge Andrés Perdomo Calvo, Ana María Jaramillo Pérez Optimal extraction policy when the environmental and social costs of the opencast coal mining activity are internalized: Mining District of the Department of El Cesar (Colombia) case study, Energy Economics 59 (Sep 2016): 159–166.

Disclosed is a method of mining or extracting a support pillar from an underground room and pillar mining operation which includes forming (by eg forming top and bottom wedge shaped cuts) at least one removable segment in a pillar (7) and moving (eg pulling) the segment substantially intact from its original location (10A) to a mining position (10C) distal from its original location ...

CBM. CBM extraction instead of coal mining in gas-producing coal beds would allow for the utilization of a potential energy source while re-ducing many harmful emissions, hazards of traditional coal mining, and the environmental impact caused by mining coal. The U.S. has large reserves of both coal and natural gas (Tables 1

extraction panels were both long and narrow (2,500 m long and 195 m wide) resulting in a panel width to depth below Coal pillar extraction experiences in New South Wales The Journal of The South African Institute of Mining and Metallurgy MAY/JUNE 2002 209 Figure 2—Typical plan view of …

Optimal Extraction of Coal From Developed Pillars Locked-Up under Different Surface/Sub-surface Structures. July 2016; ... Journal of Mining Science. 29:146-151. Sheorey P.R. (1994). "A theory ...

level of coal losses during its extraction from protecting pillars of one of the main mine workings has been determined, which is in the range of 20-30%. Keywords: auger mining, thin coal seam, protecting pillars, interwell pillar, stress, drilled well, geomechanical model.

Plan compliance process for underground coal mines. May 2010. Journal- South African Institute of Mining and Metallurgy 110 (5):241-250. Authors: Angel Angelov. University of the Witwatersrand. K ...