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MINING METHODS (UNDERGROUND COAL) 1.0 INTRODUTION TO UNDERGROUND COAL MINING : 1.1 Classify Underground Coal Mining Methods. Method of winning coal in underground mines are classified into two main categories : 1. Bord and pillar (also known as pillar and stall) and its modification. 2. Longwall (i) Advancing, (ii) Retreating.
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Here's a step-by-step guide to how a room and pillar mine is developed. 1. Exploration. First, a deposit must be identified and determined as suitable for this technique. Coal, iron, and uranium are …
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Journal of the South African Institute of Mining and Metallurgy September, 1967. A METHOD OF DESIGNING BORD AND PILLAR WORKINGS. By M. D. G. Salamon*, Dipl. Eng. (Min) (Hungary), Ph.D. (Durham) (Member) SYNOPSIS. The object of this study is to formulate a procedure for the determination of mining dimensions in bord and pillar …
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Chikande et al. (2022) created and implemented a ventilation-on-demand (VOD) system for the bord and pillar mining method at a platinum mine in Zimbabwe to reduce the usage of excess air in the ...
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The paper points out that bord-and-pillar mining is the most important method of coal extraction in South African underground coal mines, and advocates that pillar design procedures should be ...
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3) Aashutosh Chhirolya, Design of BORD and PILLAR method in coal seams. 4) J.T. Jordaan, Bord-and-pillar mining in inclined orebodies. 5) Wikipedia: Room and Pillar Method. 6) Minewiki: Bord and pillar …
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Bord-and-pillar mining has some favourable promises such as improving labour difficulties, lowering operating costs and providing safer working conditions. The success of mechanized bord-and-pillar mining in narrow tabular steep dipping orebodies will depend on the extent of the research and development efforts which need to create …
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different bord-and-pillar layouts were designed. These layouts were then evaluated according to dilution, produc-tivity, cost implications, profit and mining flexibility and the …
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The Bord and Pillar mining method is an efficient and regulated process that balances coal extraction with structural safety. Through the use of advanced …
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Bord and Pillar method of mining. Bord and Pillar method of mining is one of the oldest methods of mining. The success of Bord and Pillar mining is selecting the optimum pillar size. If the pillars are too large, then the extraction ratio decrease leading to less production and profitability and if the pillars are too small it
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Load on the Pillar = 9.81 x 2.5[(40+170).400 – (1702cot31˚)/4].(40 + 5.5)/402 = 50.197 MPa. FOS of the pillar = Load on the Pillar / Pillar Strength = 20.467 / 50.197 = 0.4. For a factor of safety of less than 1.0 a pillar is likely to collapse, therefore this pillar will collapse after the longwall has passed on both sides of the pillar.
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comes from room-and-pillar mining. Metallic minerals valued at about $1 billion, plus nonmetallic minerals valued well in excess of $1 billion, are also produced via room-and-pillar mining. A significant ($600 million) and growing portion of stone and aggregate production uses room-and-pillar mining. In addition, many other mineral commodities
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The meaning of BORD-AND-PILLAR is of or relating to a system of coal mining in which tunnels are driven in a checkerboard pattern having massive square pillars between them which are gradually cut away as the work proceeds.
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Bord-and-pillar mining is used in first workings of a deposit, and when irregularly shaped deposits, or sensitive environmental conditions, call for a lighter touch.
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Instrumentation and monitoring is undertaken aiming at evaluation of changing values of rock mechanic parameters, namely, dilation, load, convergence, and stress, during mining for a safe strata control. It enables the mining practitioners to anticipate roof fall–related dangers in advance and taking subsequent preventive …
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The mine produces washed prime coking coal. The colliery is currently being operated in Seam 9 and Seam 11 employing the bord and pillar method. It should be mentioned here that the bord and pillar mining method comprises two phases, i.e. development and depillaring.
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The significance of mining to human civilization is undeniable. Mining, being one of the earliest human endeavors, and its evolution are inextricably linked to cultural advancement. Mining is the cradle of all other businesses. Different strategies have been approached for mining effectiveness while keeping output and safety in mind. The Bord and Pillar …
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Bord & Pillar Mining Methods Fundamentally, the bord and pillar method of mining coal seams involves the driving of a series of narrow headings in the seam parallel to each other and connected by cross headings so as to form pillars for subsequent extraction, either partial or complete, as geological
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The Bord and Pillar mining method is a critical underground mining technique used for coal extraction. This method involves the creation of galleries and the strategic placement of pillars to support the roof.
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Mine capacity, Pillar and /or pillar and panel system relating to depth of working, productivity and panel extraction system, ... In NSW the size of the pillar is restricted to a minimum of 1/10 of the depth, and the width of the bord to 5.5 m. Special exemptions are required for driving bords (roadways) wider than 5.5 m. The roadways are ...
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The mining layout is exactly the same as that of the normal bord and pillar layout (see Figure 3). The bords are 4 m wide and pillar sizes are 13 m x 13 m, thus creating centres of 17 m. The stopping width in the development phase is 1.8 m (0.2 m hanging wall, 0.8 m UG2 reef and 0.8 m footwall). The pillar that is created is then stoped out ...
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The key to the successful Bord and Pillar mining is selecting the optimum pillar size. If the pillars are too small the mine will collapse. If the pillars are too large then significant quantities ...
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4.3.3 Irregular Bord and Pillar Layouts. Pillars of irregular size, shape and height, such as those shown in Fig. 4.9, were a common feature of bord and pillar mining in the days of hand mining and drill and blast mining operations. A need to assess pillar load in irregular mine layouts often arises when considering the potential for surface ...
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Coal mining - Underground mining: In underground coal mining, the working environment is completely enclosed by the geologic medium, which consists of the coal seam and the overlying and underlying strata. Access to the coal seam is gained by suitable openings from the surface, and a network of roadways driven in the seam then facilitates …
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3. INTRODUCTION In India, about 98% of underground output of coal is obtained by Bord and Pillar method and barely about 2% by longwall methods. The other countries where Bord and Pillar method predominates are Australia, The USA and South Africa. The key to the successful Bord and Pillar mining is selecting the optimum pillar …
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The mining layout is exactly the same as that of the normal bord and pillar layout (see Figure 3). The bords are 4 m wide and pillar sizes are 13 m x 13 m, thus creating …
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The Maxwell Underground Coal Mine is estimated to contain approximately 670 million tonnes (Mt) of measured and indicated resource including 100Mt as inferred coal resource. Mining operations. The Maxwell underground mine will utilise the bord and pillar, as well as the underground longwall extraction methods.
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Figure 1. Idealised bord-and-pillar layout., the average pillar stress (APS) is given by (Ryder and Jager, 2002):APS = ρgH– ewhere ρ is th. density. ation(1) can be written as …
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Introduction. In India, underground coal production is mostly dependent upon the conventional bord and pillar (room and pillar) method of mining, although the overall output per man shift (OMS) through this method is generally not more than 1. ton in any of the mines [1].. Large areas in all the subsidiaries of Coal India Limited and even in …
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