Where, is the Pillar strength equation pillar strength, is the coal strength parameter = 4.8 to 7.0 MPa (700 to 1000 psi) is the pillar width and is the pillar height. Jawed et al. 3 Pillar strength equation by Greenwald Greenwald et al. (1941) considered in situ tests on

Here the circumstances of bord and pillar mining are to face difficult surroundings, mainly, due to rock-mass characteristics and stress conditions of the deep horizon. ... To achieve a better strata condition under high stress regime of deep cover, even splitting of pillar is avoided (Mark et al., 2002). Splitting requires support placement ...

Among the currently used methods for moderately dipping medium-thick orebody mining, the room and pillar mining method accounts for 55% of cases, whereas the inclined drawpoint in footwall method ...

In FY2015 Impala produced 575 200 ounces of refined platinum. 2 IMPALA. 3 Both the Merensky and UG2 Reefs, which are contained ... Mechanised bord and pillar mining occurs in selected Merensky Reef areas on two of the shafts (12 and 14 Shafts). Mining currently extends to a depth of around 1 000 meters, with most

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 ...

The in-panel pillars are intended to provide support resistance sufficient to prevent "backbreak" type in-panel failures, while yielding in a stable manner. As such, they are …

The mining method is a mechanized bord and pillar layout, which will yield a total of 185 000 tons at full run of mine production from the underground UG2 mine. ... Impala Platinum & JV Lonmin PLC Northham Platinum Limited Southern Era Legend Leuconorite Chromitite Pyroxenite Chromitite Pyroxenite Chromitite Pegmatoid

It has five coal seams, each separated by a soil layer and is mined using the Bord and Pillar method of underground mining (Ranjan et al. 2013, K.D. Singh, Survey Officer, Bhurkunda UG mine ...

Styldrift Mine (Styldrift), a twin vertical shaft system, is a mechanised bord and pillar mining operation with an average mining depth of 680m BRPM concentrator, is a 250ktpm capacity traditional MF2 process ... l Impala Platinum Holdings Limited (40.11%) l Northam Platinum Holdings Limited (34.52%) l PIC (9.26%) l Royal Bafokeng Holdings (3. ...

The Hedley and Grant pillar strength formula is widely used within the South African mining industry to calculate pillar strengths in bord and pillar mining layouts, and is currently being used at Bathopele Mine. Bathopele is an operation of Anglo American Platinum near Rustenburg, mining the UG2 reef at depths ranging from 40 m to 300 m …

Watson et al. (2008) (linear formula) Impala Platinum, South Africa. Watson ... The paper points out that bord-and-pillar mining is the most important method of coal extraction in South African ...

Mechanised bord and pillar mining occurs in selected Merensky Reef areas at 14 Shaft. Mining currently extends to a depth of around 1 000 metres, with most operations ...

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 normally driven in rectangular shape.

Watson PB, Ryder JA, Kataka MO et al. 2008. Merensky pillar strength formulae based on back-analysis of pillar failures at Impala Platinum. The Journal of the Southern African Institute of Mining and Metallurgy, Vol.108, pp 449-461

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 measures while depillaring. The …

Sort-well is a combined method of bord and pillar and longwall mining underground coal mines[3]. Underground coal gasification (UCG): It is a process in which coal is converted to useful gases internally without requiring a mining operation. The gases can subsequently be used to produce heat, generate power, or ...

The Merensky and UG2 reefs are mined concurrently and the mining method is predominantly conventional breast mining. Mechanised bord and pillar mining occurs in selected Merensky Reef areas on two of the shafts (12 and 14 Shafts). Mining currently extends to a depth of around 1 000 meters, with most operations

Where, is the pillar strength, is the coal strength parameter = 4.8 to 7.0 MPa (700 to 1000 psi) is the pillar width and is the pillar height. Aadidev et al. 3 Pillar strength equation by Greenwald Greenwald et al. (1941) considered in situ tests on slender pillars of size 30 cm and gave the strength of pillar as: (5) Where, С p

Currently, raw coal mined through either long wall or bord and pillar mining methods and undergoes primary crushing underground. The De-stoning Plant is proposed to be built on a brownfields site, consisting of transformed land, agriculture and degraded grassland and will link into the existing mine and Eskom infrastructure.

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 extraction …

ON Guidelines for Pillar design i. ar operationsList ofFiguresFigure 1: Idealised bord-and-pillar layout.7. crease in extraction ratio with an increase in depth (pillar height = 2 …

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 strength and the appropriate formulae to use when designing hard rock bord ...

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 ...

The more recent establishment of a number of mines on the Eastern Limb, of which the TRP is an example (von Gruenewaldt et al. 1990; Mabuza 2006; Voordouw and Beukes 2009;Voordouw et al. 2010;Rose ...

underground coal mining worldwide. Even after adoption of the longwall method, room and pillar is still used for panel development and is also favored in some mines owing to attenuation of subsidence. However, designing coal pillar geometry is a key issue for the success of bord and pillar mining operation. To design a pillar, it is essential

pillars for use with a mechanised mining operation at depths of between 850 and 1 200 metres below surface. INTRODUCTION Although the use of mechanised bord-and-pillar type mining with pillar support is common in the shallow (<500m below surface) bushveld chrome mines, the platinum mines have traditionally

The bord and pillar mining method is employed and stoping widths average around 2m. Mining bords advance along the strike. The mining cycle involves mechanised support …

The object of this study is to formulate a procedure for the determination of mining dimensions in bord and pillar workings. This is achieved by using the recently reported pillar strength formula which was derived statistically from the results of a survey of mining dimensions carried out in the collieries of the Transvaal and Orange Free State. In this …

FACT SHEETIMPALAImpala, Implats's 96% owned primary operational unit has operations situated on the western limb of the world-renowned Bushveld Complex near Rustenbur. …

This study explores the use of backfill in hard rock bord-and-pillar mines to increase the pillar strength and extraction ratio at depth. The use of backfill will also minimize the requirement for ...

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 …