Historically, the mining of the available coal reserves was never carried out with the intention to conduct pillar extraction on retreat, and hence the original pillar design was usually based on the maximum percentage extraction to be achieved during the primary development mining phase 6. Bord and pillar mining has been the prime method ...
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A. This document describes a project report submitted by Anurag Kumar Jha for the partial fulfillment of requirements for a dual degree in mining engineering. The report focuses on designing a support system for bord and pillar mines. Currently, CMRI-RMR and NGI-Q systems are commonly used in Indian coal mines to estimate rock load and …
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This research makes a critical review of the current design approach so as to understand the contributors to pillar failure in a section of an underground platinum bord and pillar mine.
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8.3.1: Room and Pillar Method. Room and pillar mining is arguably the most important underground mining method in practice today. The majority of underground production comes from room and pillar mines, and the majority of underground mines, by number, employs the room and pillar method! Think about that! Let's start out by looking at this ...
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Bord and pillar mining involves driving headings into the coal seam to form pillars for extraction. Pillar extraction methods using continuous miners involve splitting or stripping pillars left from initial development. The document provides details on various pillar extraction techniques like pillar splitting, stripping, and split and ...
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Abstract and Figures. Any bord and pillar platinum mine thrives on effective design of bords and pillars. Pillars have to be large enough to ensure safety and small enough to ensure economic and ...
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The document discusses the bord and pillar method of underground coal mining. It involves driving parallel roads called bords separated by coal pillars. Development involves driving the bords and pillars, followed by depillaring which extracts the pillars. Factors like seam thickness, depth, and roof/floor strength determine suitability. Support systems like …
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Mining in the Sigma sub-basin began in the early 1950s at the Sigma Colliery. Early bord-and-pillar extraction mining methods however left much of the resource unmined, and during the 1960s total extraction methods, such as long walling and pillar extraction, were introduced to improve extraction (Cillié and Savage, 1961).
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The study deals with modern strata management, mainly strata control monitoring with analysis of roof–floor convergence, monitored induced stress, and assessment of ultimate mining-induced stress, preferably the vertical component during final extraction in a bord and pillar conventional Indian underground coal mine, Govinda Colliery, a mine ...
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Underground mining of coal results in voids with remanent pillars to support the overlying strata. Failure of any individual pillar overloads adjacent pillars and may result in failure propagation with damaging surface subsidence.It has been shown that coal pillar strength can be estimated from the attributes of effective width and height, however 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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This diagram shows the traditional method of bord and pillar mining. Miners extracted coal along roadways or bords, with the coal between the bords acting as pillars holding up the …
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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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Pillar extraction, (also referred to as retreat mining; pillar recovery; stooping; pillar robbing; and bord and pillar second workings) is the practice of forming a series of pillars and then partially or totally extracting some or all of the pillars, usually with mining operations retreating out of a panel. There are a number of basic pillar …
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Room and pillar. Room and pillar is also known as bord and pillar is a mining system in which the mined material is taken out across a horizontal plane while leaving "pillars" of unscathed material to support the overstrain leaving open regions or "rooms" underground. It is normally utilized for fairly flat-lying deposits, like those that ...
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Guidelines for hard rock pillar design in South African bord-and-pillar operations are presented in this report as well as a proposed multi-year research project to address the …
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Among different methods of underground mining technology adopted for coal extraction, bord and pillar mining is the most popular and predominant method of underground mining in India. This method is characterised with small capital investment and faster rate of return on capital. Varying geomining conditions demand scientific …
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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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This paper addresses the critical parameters that need to be considered when designing a mechanized bord-and-pillar mining layout for a narrow tabular steep …
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Mining in this panel was undertaken with two, three or some-times four passes of a roadheader cutting overlapping sections of approximately 2.44 m.With this information it is believed unlikely the original pillar heights are less than 4.3 m or greater than 7.9 m, and so the fitted normal distribution is truncated at 4.0 m and 9.0 m.The …
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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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As bord and pillar workings are developed roof support becomes a major consideration and operating cost item. Support requirements vary considerably and are dependent on the physical conditions in the seam, which are often depth dependent, and the length of time that the workings are required to be serviceable. ... In underground mining, first ...
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In coal mining: Room-and-pillar mining. …two main room-and-pillar systems, the conventional and the continuous. In the conventional system, the unit operations of undercutting, drilling, blasting, and loading are performed by separate machines and work crews. In a continuous operation, one machine—the continuous miner—rips coal from …
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Bord and pillar mining. This diagram shows the traditional method of bord and pillar mining. Miners extracted coal along roadways or bords, with the coal between the bords acting as pillars holding up the roof. The outer pillars were then mined, leaving the roof to collapse in a controlled way as the miners retreated towards the exit.
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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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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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mining and its development correlate closely with cultural progress. Mining processes involve prospecting for ore bodies, analysis of the profit potential of a proposed mine, extraction of the desired materials. One of such methods is the Bord and Pillar method of mining. Bord and Pillar method of mining is one of the oldest methods of mining.
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Mine Portal - India's Mining Exams Test Series Provider, Mine Portal is the favorite choice of thousands of mining professional aspirants for online exam preparation. ... Bord and Pillar method: Schemes of development; design of bord and pillar working; statutory provisions; selection of equipment for development -mechanised …
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As bord and pillar workings are developed roof support becomes a major consideration and operating cost item. Support requirements vary considerably and are dependent on the physical conditions in the seam, which are often depth dependent, and the length of time that the workings are required to be serviceable. ... In underground …
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The method used is the room and pillar mining method where the initial entry galleries are driven into the coal seam starting from the surface excavation face, as used in the highwall mining cases. The design of the mining scheme is presented in detail along with the building of the 3D numerical model which simulates the overall devel-opment of ...
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Two bord-and-pillar layouts were designed for this area. Layout 1 is characterized by the use of strike conveyors to convey ore on strike with an average LHD hauling distance of 35 m. Layout 2 ...
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Generally, In-situ stresses are mostly static, but induced stress developed over pillars and stooks continuously changes at various stages of underground coal mining activities. 1 The bord and pillar mining method is used to operate roughly 70–80% of India's underground coal mines, in which 3000 MT of coal reserves are located in coal ...
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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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Bord-and-pillar mining explained. By Ben Langford. Updated June 1 2017 - 9:14pm, first published May 30 2017 - 7:47pm. Shear size: A longwall miner in action on the coal face underground.
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