When the longwall (LW) face is approaching its finishoff line, the coal mining process generally slows down and then stops to allow the LW equipment to be relocated to a newly prepared installation face following standard procedures, which usually takes approximately 1 ~ 2 months (Kang et al. 2016).During this period, the air is highly likely to penetrate into the active goaf via various ...
Coal mining, extraction of coal deposits from the surface of Earth from underground. Coal has been used since the Bronze Age, 3,000 to 4,000 years ago, and was the basic energy source that fueled the Industrial Revolution of the 18th and 19th centuries. ... The other principal method of modern mining, longwall mining, had been introduced as ...
Longwall top coal caving (LTCC) mining is the most efficient method for thick and extrathick coal seam extraction. It is extensively applied in western China. 15 As illustrated in Figure 1, ... coal mining is in the process of being transformed from automation to intelligent mining. Nowadays, highyield, highefficiency automatic LTCC mining ...
Longwall mining of coal is a high production and high productivity method, employing sophisticated electrical, mechanical, and hydraulic systems, as well as computerbased monitoring and control systems. Most modern (coal) longwall faces are semiautomated.
The basic principles of longwall mining involves a coal bed being selected and blocked out into a panel (Fig. 1) averaging nearly 100350 ... In the extraction process, barrier pillars of coal are left untouched in certain parts of the mine to support the overlying strata. The minedout area is allowed to collapse behind the working face ...
Longwall shearer positioning with an inertial navigation system (INS) aided by an odometer is the key technology for automation of the longwall coal mining process.
Longwall mining concept showing (A) an oblique view of the longwall operating, (B) a close up of the shearer, and (C) a profile view of the overburden. Image from NIOSH. Coal mines tend to produce many more seismic events than hardrock mines, which makes it difficult to process the data quickly enough to be meaningful.
The DsLMF+ dataset of the coal mine image in the fully mechanized longwall mining face has been publicly available at the figshare data repository annotations include YOLO format and COCO ...
Wang et al. (2022) proposed a Gompertz time function model suitable for the longwall coal mining process based on the "three original consistency" modeling idea. Through comparison with the ...
Longwall mining technology . Longwall coal mining is an extraction process in which large panels of a coal seam up to 7 m thick are completely mined in a series of slices. Fundamental equipment in modern longwall mining are the armoured face conveyor (AFC), powered supports and the shearer (coal cutting machine) (Figure 1).
As is known, the movement of rock strata and ground caused by longwall coal mining is a complicated spatialtemporal process. There are many factors controlling the evolution of movement of caved and fractured zones, such as mining height, mining and roof control methods, rock property and stratigraphic sequence, dip angle, mining sufficiency ...
Abstract and Figures. This paper describes recent advances in the development of an integrated inertial guidance system for automation of the longwall coal mining process. Significant advances in ...
The main productive coal seam in Qianqiu coal mine is the coal seam which is cut apart by F 16 fault (near eastwest compressive torsional thrust fault) during its formation and development. 21221 mining face with the longwall mining method is a typical longwall panel. Figure 2 presents mining layout of 21221 longwall panel and the southern boundary of 21221 longwall panel is adjacent ...
The longwall machine's mine the coal in horizontal, "panels" that are 800 to 1,500 feet wide and 2 to 3 miles long. In longwall mines as the temporary support protecting the miners is advanced, the roof in the minedout area behind it collapse causing cracks and rock movement that reaches to the land surface hundreds of feet above.
First Online: 03 February 2016 2464 Accesses Abstract Since the early 1980s, the longwall method has developed into the safest, highest producing and most productive form of underground coal mining, rivalling the performance of many surface mining operations.
numerical stress analysis tools for deep coal longwall panels under strong strata. SME preprint 09011. Littleton, CO: Society for Mining, Metallurgy, and Exploration, Inc. Maleki H [1995]. An analysis of violent failure in coal mines: case studies. In: Maleki H, Wopat PF, Repsher RC, Tuchman RJ, eds. Proceedings: Mechanics and Miti
Context 1 ... mining has become a standard technology for excavating coal from underground mines [4]. This technology, summarized in Figure 1, employs a longwall shearer which is a machine...
The interruption of a coal extraction process in the longwall results in the relative stabilization of pressure redistribution. ... Zhingel, A method to forecast coal of the stopefissure network contact while longwall mining of coal seams. Coal 1970, 1, 5859. [Google Scholar]
Space adaptability between mining equipment and coalrock mass, to ensure the machines cut in a coal seam, is an importance technique in longwall mining automation. In order to guide the mining equipment cutting in the coal seam, a cutting path planning method based on multiple hierarchical clustering was proposed. Morphology similarity and the coplanarity measurement method were defined to ...
Longwall mining accounts for around 90 per cent of Australia's underground coal production. Traditionally a mechanical shearer cuts along the coal seam beneath a roof supported by hydraulic jacks, exposing miners to multiple risks on a daily basis.
The longwall room and pillar mining method is a mining method that combines room and pillar mining technology with the longwall mining layout. The coal pillar and the mining width are designed using the room ... Long wall mining is a mostly automated process whereby longwall mining machines are used to extract blocks of deposits as wide as the ...
Large scale mechanised mining methods we use include: longwall mining, where a long wall of coal is mined in a single slice, usually by a large machine. sublevelcaving, where levels of the ore are blasted by explosives; and ; block caving, where large areas of the ore body are blasted and then extracted with the assistance of gravity.
The transition of mining from surface mining to underground mining is being considered to extend/enhance coal production. Longwall mining is a typical underground coal mining method with a high production rate. However, the guidelines for a longwall mining operation in other countries with major coal mining operations are not applicable to ...
Coal production from the 36 longwall faces represented % of the 597 million tons of coal produced in the last year. Last year, two longwall mines ceased production and one new mine will start production later this year. The total number of faces dropped from 37 to 36 and the total number of longwall mines declined from 33 to 32.
The overburden rock strata fractures and collapses as the extraction of a longwall panel. Knowledge of the extents and characteristics of the fractured zone is important to evaluating many mininginduced issues including abutment pressure relief, methane production, and ground subsidence prediction. In this study, a physical model was initially created to produce the process of longwall mining ...
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