Journal of the Southern African Institute of Mining and …
The fewer elements that are used to simulate a pillar and the larger the elements, the less marked this effect becomes. In practice, for most shallow bord and pillar coal mining situations, it has been found that at an element size of 3 m, the peak stress should be increased by 3.5%, while it should be increased by 18% if 1 m elements are used.
EVALUATION OF BORD AND PILLAR MINING SYSTEM …
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.
Developments Made for Mechanised Extraction of Locked …
Bord and Pillar method of underground mining has been used extensively to develop Indian coal seams into pillars and galleries. This results in only 20–30% recovery of coal and rest coal remain locked up in developed pillars. Indian coalfields are famous in the world for its uniqueness and complexity of the geomining conditions which makes the …
Bord and Pilar (B&P) layout of underground …
The working is done in the Bord and Pillar (B&P) system which is the main method of underground working in India (Figure 1). In this method, coal transportation is done by side discharge loaders ...
A method of designing bord and pillar workings
Pillar width in feet (w) ..... 9—70 11—52 Percentage extraction (per cent) 37—89 45—91 Width-height ratio (w/h)..... OO oo 1
9: Illustration of Bord and Pillar Mining Method …
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.
Superiority of neural networks for pillar stress prediction in bord …
Estimation of pillar stress is a crucial task in underground mining. This is used to determine pillar dimensions, room width, roof conditions, and general mine layout. There are several methods for estimating induced stresses due to underground excavations, i.e., empirical methods, numerical solutions, and currently artificial …
Matla shortwall long on performance
The second shortwall will replace existing production capacity from the No 1 and No 3 mines presently exploited by continuous miner bord and pillar methods. Matla was the first mine in South African to develop a mine based exclusively on continuous miner bord and pillar panels - at the time unproven in the country.
Bord & Pillar Method | PDF | Mining | Coal
Bord & Pillar Method - Free download as Powerpoint Presentation (.ppt), PDF File (.pdf), Text File (.txt) or view presentation slides online. The bord and pillar mining method …
Robust Design of Pillar Arrangement for Safe Room-and-Pillar Mining
The arrangement of pillars is a key design parameter in the execution of the room-and-pillar mining method. The objective of this study is to provide safe, reliable and a robust design for pillar arrangements for economic and efficient mineral recovery. Four design parameters have been considered in this study, including the degree of pillar …
Bord-and-pillar mining in inclined orebodies
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 ...
Room and pillar mines, Mining Techniques, Underground Mining…
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 ...
Mine Health and Safety Council
In 2013, a Bord and Pillar Task Team was established by the Department of Mineral Resources (DMR) Principal Inspector of the North West Region, to determine current industry best practice for bord and pillar mining (Platinum Task Team, 2013). It was found that there was a variation in the methodologies used to design bord widths but
Depillaring: Arrangement, Precautions and Pillar Extraction …
1. Introduction to Depillaring: After pillars have been formed on the bord and pillar system, consideration has to be given to the extraction of coal from the pillars; the operation is known as pillar extraction. It is also referred to as depillaring, pillar-cutting or broken working. ADVERTISEMENTS:
Research on overburden structural characteristics and …
Combined with the relevant parameters of the coal pillar area of the 14,022 collaborative mining face: the width of the coal pillar area l = 35 m, the thickness of the upper layered coal seam m 1 ...
FIRST WORKINGS – Mining Science and Technology
The size of the pillars and headings driven during the first working stage is restricted by statutory requirements of a particular State. 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.
Coal pillar extraction at deep cover: With special reference …
Research Highlights Indian geo-mining scenario of coal pillar extraction is provided. Status of bord and pillar mining for deep coal seams is reviewed. Inherited instability issues of natural support during depillaring of a deep seam under competent roof (high stress conditions) are discussed. Influence of caving of competent overlying strata …
Bord-and-pillar mining in inclined orebodies
Synopsis. 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 …
OPTIMIZATION OF MECHANIZED MINING LAYOUT …
• Bord and pillar (1.8 m–2.2 m stope widths using low-profile (LP) mechanized equipment) • Breast mining (1.3 m stope width using extra-low profile (XLP) mechanized equipment) A graphical representation of the bord and pillar and mechanized breast mining methods is shown in Figure 1 and Figure 2. It is important to note that the ...
An approach for support design in depillaring panels of …
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 …
TYPE OF PILLARS – Mining Science and Technology
A single line of square chain pillars separate two longwall panels. A 2.8m thick coal seam is being mined at a depth of 400 metres below the surface and the longwall face is 170 metres wide. Given that: Average angle of shear f = 31˚. Width of the roadways/bords = 5.5 m. Overburden density g = 2500 kg/m3.
Managing the geotechnical and mining issues surrounding …
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 ...
Multi-seam coal mining
The panel parameters were calculated using the CSIR Mining-Tek programme. The programme uses the Salamon and Munro formula to calculate various panel parameters. The safety factor for square pillars may be determined by dividing the strength of the pillar by the load on the pillar. The desired safety factor, bord width, mining height, and
Bord & Pillar Mining Methods
The bord and pillar method of mining is suited to work flat coal seams of average thickness and at shallow depths. Coal seams of 1.8 to 3 m thickness are best suited for this …
Guidelines for Pillar design in Bord-and-Pillar operations
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 …
Evaluation of Bord and Pillar Mining System in …
The objective of the investigation is to evaluate the extraction ratio in Bord and Pillar mining. system and to find the factor of safety for pillar design with respect to a particular mine. The ...
Evaluation of different methods of pillar recovery in coal mining …
The room-and-pillar technique is a self-supporting mining method in which part of the ore is left unmined as pillars. To increase the mining efficiency, the pillars are later recovered partially or completely. This research aims at evaluating and comparing four methods of pillar recovery, namely, 'pocket and wing', 'open ending', 'split and fender', …
Microsoft PowerPoint
Tabular deposits Flat - <350 dip Wide Reef – Bord and Pillar, Drift and fill Considerations: • Span between pillars • Fill material availability • Subsidence • Geological weaknesses particularly jointing, potholes, triplets, smectites,
Room and Pillar Mining
Two dominant methods together account for the vast majority of underground coal mining: "room and pillar" and "longwall" mining. In room and pillar mining, seams of coal are mined partially, leaving large pillars of coal intact to support the overlying layers of rock.Mining by this method creates a network of alternating open spaces and large …
[PDF] Pillar design in coal mines | Semantic Scholar
The paper points out that bord-and-pillar mining is the most important method of coal extraction in South Af~ican underground coal mines, and advocates that pillar design procedures should be refined to make more rational allowance for the differences in strength properties between various coal seams and roof and floor strata. However, any …
OPTIMIZATION OF MECHANIZED MINING LAYOUT …
The current mining methods that were evaluated for the purposes of the study were conventional scattered breast mining, bord and pillar (LP) and mechanized breast …
An evaluation of the equipment used in South Africa for …
The bord-and-pillar method of mining is used in South Africa to extract more than 60 per cent of the coal from thin seams!. The total production accounted for by this tech-nique of mining in narrow seams is, however, small. In 1981, there were only fourteen mechanized production sections in South Africa in which the bord-and-pillar
(PDF) STUDY AND REVIEW OF ADVANCE DEPILLARING METHODS …
Limitations of auger mining: Lack of sufficient power to drill a large diameter hole deep enough. Lack of a method of steering the cutter head to avoid cutting roof and floor. 4.1.2 Bord and Pillar mining: This method is sometimes called room-and-pillar mining. It is commonly used for flat or gently dipping bedded ores or coal seams.
Bord & Pillar – Mining Science and Technology
The BLS were originally pioneered in the RSA at Middlebult Colliery by Voest-Alpine commencing in 1984 and later trialled in several Australian collieries commencing in 1987. Their subsequent use in pillar extraction panels has become widespread with some 60 units in operation by 1991. A BLS units is illustrated to […]
Maxwell Underground Coal Mine, New South Wales, …
The Maxwell underground coal mine sits within the EL5460 mining and exploration license, approximately 16km south-southwest of Muswellbrook, in the Upper Hunter Valley of New South Wales, Australia. ... The Maxwell underground mine will utilise the bord and pillar, as well as the underground longwall extraction methods. The run-of …
A review of the pillar design methodology for manganese mining …
Dissertation (MEng (Mining Engineering))--University of Pretoria, 2022. This study describes a review of the pillar design at the manganese mining operations in South Africa with specific reference to Nchwaning III Shaft at Black Rock Mine Operations. From a literature study, it is clear that there is uncertainty regarding hard rock pillar ...
8.3.1: Room and Pillar Method | GEOG 000
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 …
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