longwall top coal caving

PAPER OPEN ACCESS Functional schemes of automated and ...

Mar 14, 2020· equipment in longwall top coal caving method (LTCC) with coal discharge to face conveyor. The application of the proposed schemes lessens the influence of the human factor, prevents coal dilution, eliminates conveyor overloading, decreases workload of shearer operator in face area and reduces the probability of making errors by operators. 1.

SMERE Longwall Top Coal Caving - Apps on Google Play

Apr 13, 2020· It is intended to provide an introduction to the longwall top coal caving (LTCC) mining method through an interactive simulation. A 360-degree view is provided of the cutting sequence at a hypothetical LTCC face. This allows the viewer to look around and observe the relationship between the supports, the armoured face conveyor (AFC) and the ...

Top Coal Caving | Longwall | underground COAL

A brief description of longwall top coal caving (LTCC) is included at the end of the Longwall section of the Fundamentals of Coal Mining module of this web site. Despite the fact that there are numerous coal seams in Australia which are thick enough for LTCC to be used to increase recoveries, potentially at a reduced cost/tonne, there has been ...

Longwall mining - Wikipedia

Longwall mining is a form of underground coal mining where a long wall of coal is mined in a single slice (typically 0.6–1.0 m (2 ft 0 in–3 ft 3 in) thick). The longwall panel (the block of coal that is being mined) is typically 3–4 km (1.9–2.5 mi) long and 250–400 m (820–1,310 ft) wide.

Longwall Top Coal Caving Mechanisms in the Fractured Thick ...

Aug 08, 2020· In this study, the finite difference method (FDM) coupled with a discrete fracture network (DFN) was utilized to analyze longwall top coal caving (LTCC) behaviors. The integrated FDM–DFN model enabled the influence of the preexisting fracture, stress redistribution, stress rotation, caving material compaction, and periodic rupture of roof ...

to Supply Two Complete Longwall Top Coal ...

The longwall top coal caving (LTCC) mining method to be employed at the Eynez East underground coal mine is a special type of longwall mining applicable to seams thicker than 6 meters (20 feet). Conventional longwall equipment has not yet been designed to operate successfully in seams thicker than approximately 6 meters (20 feet) mining height.

to supply two complete longwall top coal ...

Jul 02, 2014· The longwall top coal caving (LTCC) mining method to be employed at the Eynez East underground coal mine is a special type of longwall mining applicable to seams thicker than 6 …

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Top coal movement law of dynamic group caving method in LTCC with an inclined seam. Mining, Metallurgy & Exploration, 2020, 37(5):1545-1555. (5) Wang Jiachen, Wei Weijie*, Zhang Jinwang. Theoretical description of drawing body shape in an inclined seam with longwall top coal caving mining.

Viewpoint Mining Magazine - Longwall Top-Coal Caving

Longwall Top Coal Caving (LTCC) is a special designed longwall mining method for very thick seams (thickness is more than 4.5m) where good quality coal is being left because "conventional" longwall equipment has not yet been designed to operate successfully beyond around 5m mining height.

OptimizationofCavingTechnologyinanExtrathickSeamwith ...

e optimization of top coal caving technology is an efficient method to improve the recovery ratio in longwall top coal caving (LTCC). In extrathick coal seams, the conventional single-opening sequential caving technology (SOSCT) shows the following problems: low recovery ratio, high rock mixed ratio, and poor drawing balance.

How does Longwall Top Coal Caving work? LTCC Mining ...

Jul 19, 2018· Longwall Top Coal Caving (LTCC) is a special designed longwall mining method for very thick seams (thickness is more than 4.5m) where good quality coal is being left because "conventional ...

‎SMERE Longwall Top Coal Caving on the App Store

‎This app has been developed for the students of Minerals and Energy Resources Engineering (MERE) subjects at the University of New South Wales (UNSW), Australia. It is intended to provide an introduction into the longwall top coal caving (LTCC) mining method through an interactive simulation. A 360-…

Gob Spontaneous Combustion in a Fully Mechanized Long …

Fully Mechanized Long-Wall, Top-Coal Caving Face, Gob, Mathematical Model, Spontaneous Combustion, and Face Ad­ vancing. INTRODUCTION With the current steady increase in world coal production (3.6% annual growth) and the increasing depth at which coal must be recovered, more underground mines will be developed.

(PDF) Study on Evolution Characteristics and Instability ...

An improvement in bending moment of the overlying coal band in longwall top coal caving (LTCC) provides better under-winning opportunity for the roof coal band. An acceptable limit of 25 MPa ...

(PDF) Longwall Top Coal Caving Design for Thick Coal Seam ...

Longwall top coal caving (LTCC) is a relatively new method of mining thick coal seams that is currently achieving high productivity and efficiency in application, particularly in China.

Longwall Top Coal Caving | Introduction | underground COAL

Longwall Top Coal Caving. Longwall top coal caving (LTCC) is a special type of longwall mining applicable to very thick seams (greater than 4.5m) where good quality coal is being left because "conventional" longwall equipment has not yet been …

Energies | Free Full-Text | Longwall Top-Coal Caving ...

Longwall top-coal caving mechanisms and cavability optimization with hydraulic fracturing are analysed in this study. Based on the geological and geotechnical conditions of the Dongzhouyao coal mine, it is revealed that top-coal failure mechanisms are dominated by both compressive and tensile stresses. Ahead of the face line, shear failure initiates at the lower level of the top-coal and ...

Longwall Top Coal Caving (LTCC) Mining Technology

Longwall Top Coal Caving (LTCC) is a special designed longwall mining method for very thick seams (thickness is more than 4.5m) where good quality coal is being left because "conventional" longwall equipment has not yet been designed to operate successfully beyond around 5m mining height.

The Principle of Longwall Top Coal Caving (LTCC ...

Nov 17, 2020· Longwall Top Coal Caving (LTCC) roof supports allow mining of seams seams thicker than 6 meters (20 feet). Following a conventional cut with a shearer to about 3 m (9.8 ft) the roof supports move forward and allow the caving of the top coal behind the roof supports a second conveyor mounted gob-side.

Geotechnical Considerations for Longwall Top Coal Caving ...

Longwall Top Coal Caving (LTCC) is an enhanced form of the conventional longwall recovery system, whereby a rear Armoured Face Conveyor (AFC) (refer to Figure 3) is utilised to extract coal from behind the powered supports that would otherwise be left unrecovered in thick seam environments. The major

Longwall Top Coal Caving,Top Coal Caving,Top Coal Caving ...

Longwall Top Coal Caving (LTCC) is a special designed longwall mining method for very thick seams (thickness is more than 4.5m) where good quality coal is being left because "conventional" longwall equipment has not yet been designed to operate successfully beyond around 5m mining height.

Optimization of Caving Technology in an Extrathick Seam ...

Aug 04, 2021· The optimization of top coal caving technology is an efficient method to improve the recovery ratio in longwall top coal caving (LTCC). In extrathick coal seams, the conventional single-opening sequential caving technology (SOSCT) shows the following problems: low recovery ratio, high rock mixed ratio, and poor drawing balance. For these problems, this research verifies the applicability …

Drawing mechanisms for top coal in longwall top coal ...

Jul 21, 2021· Longwall top coal caving (LTCC) is a special type of mining method commonly used to extract coal seams thicker than 4.5 m (Wang et al. 2018a).This method originated in France and Eastern Europe in the 1950s for extracting coal pillars from marginal areas of coalfields (Wang et al. 2014).LTCC is mainly used in China these days, and has been applied in a few cases in Australia, Vietnam, Russia ...

Caving mechanisms of loose top-coal in longwall top-coal ...

Oct 01, 2014· The top-coal caving longwall mining is one of the major mining methods for extracting thick coal seams in China. The top-coal caving mining was estimated to have produced about 0.6 billion metric tons every year, accounts for 18% of underground coal mining in China .The major features of the top-coal caving mining are that a conventional longwall mining with cutting height 2–3 m is …

Longwall Mining - SlideShare

Apr 30, 2010· Longwall Top Coal Caving (LTCC) Technical Principle Of Top Caving Rock stress 1st pressure Low stress Stress 2nd pressure Compact peak abrupt drop peak stress Pressure curve of top coalseam Fracture 5600 Coal Broken Coal coal goaf caving 2800 Working Height Front AFC Rear AFC back 121. Longwall Top Coal Caving (LTCC) Supports used ...

Mining Safety of Longwall Top-coal Caving in China

Longwall top-coal caving technology has developed rapidly in China, in recent years. The application of longwall top-coal The application of longwall top-coal caving can double both the productivity and the efficiency of a working face and reduce the cost of production by 30 to 40o/o.

The Principle of Longwall Top Coal Caving (LTCC) - YouTube

Apr 30, 2015· has extensive experience in the design of roof supports for specific mining conditions. Longwall Top Coal Caving (LTCC) roof supports allow m...

Ultra-thick Seam Longwall Mining in China | Coal Age

Oct 24, 2013· In top coal caving mining, the bottom 2.5-4 m (8.1-13.1 ft) of the seam is extracted by the conventional longwall mining method and the remaining roof (top) coal is naturally caved behind the shield. In this method, there are two armored face conveyors (AFCs) at the longwall face, the front one located in front of the shield legs is operated ...