Top Coal Movement Law of Dynamic Group Caving Method …
Abstract. Due to the unbalanced top coal drawing process, the recovery ratio is low, and the equipment stability is poor in the longwall top coal caving mining …
Stability Mechanism and Control Technology for Fully Mechanized Caving
Top-coal caving mining was first applied to the mining of steep coal seams in France, Spain, and the Socialist Federal Republic of Yugoslavia in the early twentieth century; the technique was later extended to thick coal seams in the mines of the Soviet Union, France, and other countries during the early 1950s [].Fully mechanized …
Stress analysis of longwall top coal caving | Request PDF
Top coal caving mining is the important mining method for thick and extra-thick coal seams: in the coal dropping stage of the top coal caving, the hydraulic support is parceled in the floor rock ...
4.3.2: Underground Mining Methods | GEOG 000
Longwall mining. Longwall mining is a type of caving, applied to a horizontal tabular deposit such as coal. While block and sublevel caving are essentially vertically advancing metal mining methods, longwall mining is applied to relatively thin and flat-lying deposits – most often coal, but occasionally an industrial mineral such as trona.
Fully mechanized longwall top coal caving technology in …
The paper systematically summarized the main achievements of the fully mechanized longwall top-coal caving technology in passed 20 years in China and the conclusion and understanding on the related issues. The paper provided the issues of the theoretical and technical researches to be strengthened in the next step for the fully mechanized …
3D numerical modeling of longwall mining with top-coal caving
Model for top-coal caving. Steps of the 3D modeling of the M3 longwall face and top-coal caving are given as follows: 1. In order to obtain proper results from models formed to analyze caving of top coal, only a small part of the face was modeled. This consisted of the area of two shields located at the face center.
Numerical simulation of the top coal caving process
Since top coal caving mining method has the advantage of high-production, high-efficiency, low development ratio, and low-coast, it has developed rapidly in the past two decades and become the ...
Critical Aspects of Longwall Top Coal Caving Method for
The longwall-based top coal caving methods (LTCC) are developed and excelled in China for their production, productivity, and conservation advantages over other thick seam mining methods. ... Liu H (2014) Caving mechanisms of loose top-coal in longwall top coal caving mining method. Int J Rock Mech Mining Sci 71:160–170. …
Energies | Free Full-Text | Numerical Investigation of Top Coal …
The method enables the simulation of top coal caving mining process, including the simulation of hydraulic support and rear scraper conveyor; furthermore, it enables the automatic control of simulation process by using Fishcall function. However, there are obvious limitations and weaknesses in this method.
Caving mechanisms of loose top-coal in longwall top-coal …
The top-coal caving mining method, developed steadily in the past two decades, has become the main method for thick seam coal mining in China. In recent …
Force chains in top coal caving mining
The fully mechanized top coal caving mining face 8512 in Chenjiagou coal mine of Huating Coal Group in China was selected as a case study. The extracted coal seam No.5 is buried at a depth of about 400 m with the average thickness of 10.8 m and the average inclination of 6.6°.
Dynamic Random Arching in the Flow Field of Top …
The large mining height fully mechanized top-coal caving mining technique has developed rapidly and become the most extensively used mining method for ultra-thick coal seams. The arching of …
A review of cavability evaluation in longwall top coal caving
The longwall top coal caving (LTCC) is an efficient mining method to specifically extract thick or ultra-thick coal seams due to its good adaptability with respect to the large variations of coal ...
Longwall top coal caving (LTCC) mining technologies with …
Longwall top coal caving (LTCC) mining technologies with roof softening by hydraulic fracturing method. V Klishin 1, ... The paper discusses advanced top coal caving technologies for thick coal seams and addresses some issues of incomplete coal extraction, which can result in the environmental damage, landscape change, air and …
Techno-Economic Feasibility of the Longwall Top Coal …
An extraction method for deep-seated thick seam deposits by underground mining with high resource recovery has remained a great challenge for Indian mining …
Caving mechanisms of loose top-coal in longwall top-coal caving mining
The top-coal caving mining method, developed steadily in the past two decades, has become the main method for thick seam coal mining in China. In recent years, the core research areas in the top ...
Effect of upward angle on the drawing mechanism in longwall top-coal …
In Slovenia, a lens-shaped coal deposit with a thickness of more than 160 m at the centre and pinches out towards the margins, caused by geological structure and the subsidence of the area between faults, is extracted by multi-level longwall top coal caving (also known as Velenje Mining Method, VMM) 11, 12; Gregor jeromel et. al. studied the ...
Key technologies and equipment for a fully mechanized top-coal caving …
Thick and ultra-thick coal seams are main coal seams for high production rate and high efficiency in Chinese coal mines, which accounts for 44 % of the total minable coal reserve. A fully mechanized top-coal caving mining method is a main underground coal extraction method for ultra-thick coal seams. The coal extraction technologies for …
Migration law of different top coal thicknesses in top coal caving
Top coal caving has become one of the main mining methods for thick and extrathick coal seams. Because of coal seam conditions, the top coal thickness is not constant. It is necessary to study the influence of top coal thickness changes on the top-coal-caving mining process. To explore the migration law of top coal failure, the …
Experimental and numerical investigation on coal drawing
The top coal caving mining method is used, and the cutting height is 2.5 m. The type of shield support is ZFY4800/17/28, which has a width of 1.5 m, height of 1.7–2.8 m and average caving height of 4 m. Thirty-six caving shield supports were installed in the panel face. Specifically, there are one transitive support at the upper end and two ...
Feasibility study on fully mechanized large mining height long wall top
@article{Zhou2020FeasibilitySO, title={Feasibility study on fully mechanized large mining height long wall top-coal caving mining in ultra-thick (20–30 m), parting-rich coal seams: A case study of the Laosangou mining field in China}, author={Yazhou Zhou and Dongsheng Zhang and Gangwei Fan and Shuai Zhang and Shi-lei Zhang}, …
Investigation of the effect of caving height on the efficiency …
The LTCC production method, which is shown in Fig. 1 b and applied by creating a face in the horizontal thickness of the seam investigated within the scope of the study, is also defined as the horizontal section top coal caving method, especially in studies originating from China. 3, 12, 13 The sum of the cutting and caving heights is …
Numerical simulation of realistic top coal caving intervals …
Top coal caving mining technology started in the 1980s and continues to this day 1, 2. Longwall top coal caving (LTCC) mining consists of two processes: …
(PDF) Development of 3D top coal caving angle model for …
During high-intensity, fully mechanized mining of extra-thick coal seam, the top coal would cave to a certain 3D form. Based on the data collected during drilling, a 3D model of top coal caving ...
CDEM simulation of top‐coal caving characteristics under …
Longwall top coal caving (LTCC) mining is the most efficient method for thick and extra-thick coal seam extraction. ... were installed in inclined boreholes drilled into the top coal and roof. 13 This field observation provides a direct method for top-coal deformation analysis by monitoring the vertical and horizontal displacements of the top ...
A Novel Coal-Gangue Recognition Method for Top Coal Caving …
Accurate and rapid recognition of coal and gangue is an important prerequisite for safe and efficient mining in top coal caving face. In this article, a novel coal-gangue recognition method is put forward based on an improved antlion optimization (IALO) algorithm, variational modal decomposition (VMD), and an improved MobileNetV2 network. First, …
Top coal caving mining technique in thick coal seam …
The longwall mining method was used and the whole seam thickness was mined by top coal caving method. The mining depth was 300–390 m. Coal mined in the area was No. 21 coal seam, 1.7–12.31 m thick. The average thickness was 4.65 m. The average dip angle was 10°. The recoverable reserves were 2190 thousand tons. 3.2.
Stress analysis of longwall top coal caving
Introduction. Top coal caving is an economical underground mining method, which has recently been introduced, modified and practiced in the underground coal mines of China. The method and its consecutive modifications can be linked to the original method of soutirage mining developed in France during the 1960s [1].
Longwall top coal caving design for thick coal seam in very …
Fully mechanized LTCC mining method is a good recovery for ultra-thick coal seams especially seams above 7 m. Developing technologies increases the recovery rate for LTCC more than working in slice panels (Wang et al. 2015).Different drawing alternatives effect the recovery rate of the top coal as also outlined by Wang et al. (), …
Caving mechanisms of loose top-coal in longwall top-coal …
The top-coal caving mining method, developed steadily in the past two decades, has become the main method for thick seam coal mining in China. In recent years, the core research areas in the top-coal caving mining are the mechanisms of top …
