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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.

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Longwall Top Coal Caving Introduction underground COAL

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 designed to

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Stress analysis of longwall top coal caving - ScienceDirect

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.

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A review of cavability evaluation in longwall top coal caving

01/11/2017  Longwall Top Coal Caving has been considered as one of the most effective technologies for the extraction of underground thick coal seams. A large number of studies on the applicability of Longwall Top Coal Caving into new mine sites have linked the success of its application to the geomechanical understanding of the cavability of the top coal.

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Longwall top coal caving design for thick coal seam in ...

The amount of coal for the production panel must be high enough to cover the initial investment of the mechanized longwall system. Longwall top coal caving (LTCC) is a part of longwall mining that is applicable for thick coal seams. China is an important country, which has best practices of LTCC in terms of high production rates.

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Longwall Top Coal Caving Method - SlideShare

19/02/2014  LTCC • Longwall Top coal Caving (LTCC) is a method of extraction for underground mining of thick seams. • It uses a longwall set-up and natural forces to aid in the winning of coal. 4. Problems Associated With Thick Seam Extraction • Underground Coal loss. • Heavy cost of supporting working places in productive faces. • Spontaneous ...

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Longwall Top Coal Caving (LTCC) technology - Yancoal

Developed in China, top coal caving uses a modified long wall mining system. LTCC allows the excavation of thick coal seams of 5 to 12 metres at one pass of the longwall machine, generating high productivity and economic returns for an operation.

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3D numerical modeling of longwall mining with top-coal caving

In China, the reserve and production of thick seam coals accounts for 45% of underground coal resources and production, and the longwall top-coal caving technique (LTCC) is one of the major mining methods used to extract thick coal seams.1–3The technique was first applied in the 1940s in Russia and subsequently used in France, former Yugoslavia, Hungary, Romania,

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3D numerical modeling of longwall mining with top-coal caving

01/02/2005  Longwall with top-coal-caving method as applied at Omerler underground mine. 3. Caving mechanism in the top-coal-caving methodUndoubtedly, caving of naturally fractured or blasted top coal under gravity is the most critical factor in determination of mining method-related parameters such as geometry and dimensions of longwall panel, face support and production scheduling. Top coal

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A review of cavability evaluation in longwall top coal caving

01/11/2017  Longwall Top Coal Caving has been considered as one of the most effective technologies for the extraction of underground thick coal seams. A large number of studies on the applicability of Longwall Top Coal Caving into new mine sites have linked the success of its application to the geomechanical understanding of the cavability of the top coal. The paper

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Coal Zoom Longwall Top-Coal Caving: A Productive and ...

04/12/2018  Longwall Top-Coal Caving: A Productive and Efficient Alternative . December 4, 2018 - In the right conditions, longwall mining is one of the safest, most productive and most efficient ways to produce coal. This is owed in part to the high degree of automation employed by modern longwall operations, which keeps shearers and roof supports advancing smoothly

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Geotechnical Considerations for Longwall Top Coal Caving ...

2011 Underground Coal Operators’ Conference The AusIMM Illawarra Branch 10 – 11 February 2011 31. LONGWALL TOP COAL CAVING DESCRIPTION . 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

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Application of Longwall Top Coal Caving in Challenging ...

Abstract-Longwall top coal caving (LTCC) ... Underground Water As the mining activities disturb the surrounding rock mass, fracture and channels develop, through which underground water may flow into the mining area and result in great hazard to operators’ and equipment’s safety. The disturbance to rock mass from LTCC is stronger than the ordinary longwall so that

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The Key Stratum Structure Morphology of Longwall ...

Longwall mechanized top coal caving mining (LMTCCM) in extra-thick coal seams has its own characteristics. The law of mining pressure and overlying strata failure height in extra-thick coal seams are much larger than those of medium-thick and thick coal seams. The key stratum structure morphology also has an important influence on the law of overlying strata movement

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Characterizing the Top Coal Cavability with Hard Stone ...

20/08/2018  One of the most challenging problems in longwall top coal caving is the top coal cavability. Stone bands, which are usually found in thick coal seams, have shown adverse effects on top coal fragmentation and cavability. Understanding the characteristics of the stone band caving process is a primary step in evaluating top coal cavability in such conditions. In this

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

08/08/2020  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 strata to be

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Ultra-thick Seam Longwall Mining in China Coal Age

24/10/2013  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 like conventional longwall

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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. It enables an increased recovery for only an incremental additional cost.

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

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.

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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.

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Long wall top coal caving - SlideShare

15/11/2017  LONGWALL TOP COAL CAVING Another variation of the Top Coal Caving use, where the seam thickness is over 15m.  The longwall faces are again developed. The top slice is placed so that there is 5m of coal left above the supports.  This top slice (first longwall face) is advanced as an ordinary longwall operation, leaving 5m of coal overhead.

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

A good understanding of the caving mechanisms of loose top-coal is significant for longwall top-coal caving (LTCC) mining. In this paper, the equations of the particle motion, top-coal boundary, and drawing body were derived based on the stochastic medium theory. Then, the particles moving boundary and the shape of the top-coal loss were discussed, and the dynamic evolvement of the top-coal ...

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A Brief Comparison of Longwall Methods Used at Mining of ...

Longwall (MSL), and Longwall Top Coal Caving (LTCC). In this paper these methods are compared to eachother both from the technical and economical perspectives. The advantages and disadvantages of each method are discussed. Finally it is stated that the future trend in operation of longwalls is towards LTCC method all over the world. 1. INTRODUCTION Total lignite reserves of Turkey amount to ...

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Mining Safety of Longwall Top-coal Caving in China

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. Using standard longwall equipment, annual production can reach 3 million metric tons (Mt), and a maximum of 4.1 Mt has

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Longwall Top Coal Caving Mining - vosweb.nl

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 designed to operate successfully beyond around 5m mining . Principles of Longwall Mining ...

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Overburden Failure and Ground Pressure Behaviour of ...

10 yielding, coal face spalling, strong deformations of goaf-side entry, and severe ground pressure 11 dynamic events typically occur at the longwall top coal caving longwall faces. Based on the Key 12 strata theory an overburden caving model is proposed here to predict the multilayered hard strata

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Fuqiang Gao *, Doug Stead , John Coggan

Longwall mining is a widely used underground mining method for the extraction of relatively thick, sub-horizontal and uniform coal seams. After mining of the coal seam, the panel roof strata above the mined-out area or goaf will be destressed. With continued face advance, the immediate roof will collapse and cave into the goaf area, and the disturbed roof strata gradually extends upwards ...

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Longwall Top Coal Caving Method - SlideShare

19/02/2014  LTCC • Longwall Top coal Caving (LTCC) is a method of extraction for underground mining of thick seams. • It uses a longwall set-up and natural forces to aid in the winning of coal. 4. Problems Associated With Thick Seam Extraction • Underground Coal

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Determination for Ultra-Thick Longwall Top Coal Caving ...

Longwall Top Coal Caving (LTCC) is an economical underground mining method that has been introduced and practiced in underground coal mines in China and other countries [2–4].

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Multiple-panel Longwall Top Coal Caving Induced ...

seam, the multi-level longwall top coal caving (LTCC) method is practiced at the mine. Specifically, the entire coal deposit is divided into a number of levels ranging from 10 to 20 m in thickness, and extracted sequentially from the top to the bottom. At each level, the lower section of the seam (3-4 m in thickness) is cut by a shearer under the hydraulic supports, and the top coal (7-17 m in ...

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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. History. Plan of longwall mine before conveyors – the hoist is at the center of the central ...

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Long wall top coal caving - SlideShare

15/11/2017  Long wall top coal caving 1. LONGWALL TOP COAL CAVING P SHASHIKANTH 16MT001042 2. LONGWALL TOP COAL CAVING GENERAL INFORMATION • It is the modified method of longwall mining system • Yancoal introduced the Longwall Top Coal Caving (LTCC) mining technology in Australia at its Austar mine in 2006. • This method has been developed in china in more

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Caterpillar to supply two complete longwall top coal ...

02/07/2014  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

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Strong Ground Pressure Mechanism and Control at the ...

The longwall top coal caving (LTCC) method is applied to the working face, with a mining height of 3.5 m and a caving height of 3 m. Thus, the mining-to-caving ratio is 1 : 0.86, and the average daily advance speed is 10 m/d. Based on the drill column at the working face 42107 and the key stratum theory

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Longwall Top Coal Caving Mining - vosweb.nl

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 designed to operate successfully beyond around 5m mining . Principles of Longwall Mining ...

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Longwall Top Coal Caving Application Assessment in Australia

The Longwall Top Coal Caving (LTCC) method, which is being used successfully in China, offers a great potential for thick seam extraction in Australia. The LTCC method can be used to successfully extract up to 12 meters in thick seams. Production peaks up to 7 MT per face were reported in Chinese mines with this method. However, successful application of this method in Australia requires a ...

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numerical analysis on top coal caving of coal seam in in spain

numerical analysis on top coal caving of coal seam in in spain Evolution of mining‐induced stress in fully mechanized top. Abstract The forms of roof break roof fall and effects of the region scope in a fully mechanized topcoal caving FMTC face of the 101 fullymechanized top coal caving face of the Tingnan Coalmine were analyzed by UDEC and FLAC 3D software The analysis result confirms the ...

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