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·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
·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
·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 the installation of
·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 extraction of the
The good quality coal pillars were left behind as primary support during underground bord and pillar mining operations Due to the depletion of virgin coal reserves the pillars and remnant coal are now removed using opencast mining rather than underground methods However the secondary extraction of pillars and remnant coal from the old
· Irregular Bord and Pillar Layouts Pillars of irregular size shape and height such as those shown in Fig 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
·by the highwall mining system Porathuir et al 2017 In this manner the coal is accessed from galleries starting at the base of the highwall and driving their way through the deposit Nevertheless in the case examined the exploitation is not being made by auger systems but by using the room and pillar mining scheme without any recovery of
·Bord and Pillar method of mining is one of the oldest methods The key to the successful Bord and Pillar mining is selecting the optimum pillar size If the pillars are too small the mine will
·percentage of its mines These methods are • Bord and pillar m m stope widths using low profile LP mechanized equipment • Breast mining 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
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
·tivity cost implications profit and mining flexibility and the most suitable layout was chosen Bord and pillar mining was then compared to conven tional mining according to the following financial analysis dilution and flexibility Conclusions could now be drawn to the appropriateness of bord and pillar mining in Vlakpoort and Moddergat
Bord and pillar method of mining coal seam involves driving two sets of parallel inseam headings one set being orthogonal to another thereby forming square or rectangular pillars These pillars are subsequently extracted allowing the overlying strata to cave in the decoaled area In some cases where circumstances so
·In India bord and pillar is one of the popular underground mining methods for coal extraction Bord and pillar are the two basic structures that need to be appropriately designed for the success of mining operations The performance of these structures depends on geo mining conditions state of stress and geotechnical properties of strata
·It was decided to mine the UG2 orebody with trackless equipment using a bord and pillar mining method Frank shaft has been mining the UG2 orebody for nearly 5 years The T cut mining method was
·The continuous miner uses the principle in which a large rotating steel drum equipped with tungsten carbide steel teeth or cutting bits cut the in situ coal Continuous miners are generally suitable for a room and pillar mining system The CMT can develop a virgin seam for coal extraction by the bord and pillar method
·Considering progressive pillar failures and the effect of single pillar failure on surrounding pillars this paper proposes a pillar peeling model to evaluate the long term stability of coal mines
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 of valuable material will be left behind reducing the profitability of the mine The most important parameter before designing a pillar is the Safety
·time dependent scaling of pillars in a hard rock bord and pillar mine and to compare the numerical results with eld observations Fig 1 Time dependent scaling of a manganese pillar in a hard rock bord and pillar mine in South Africa The pillar was covered with thin spray on liner to prevent the scaling but the ongoing failure
· IntroductionIn 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 Singarani Coal
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 method of mining is one among
·Bord and pillar method of mining continues to be a major operation in India with about 160 mines producing 35 MT of coal Owing to the exhaustion of near surface deposits environmental impacts and land acquisition issues associated with surface mining underground coal mining is expected to take a leap in the next decade Weak and layered roof strata in
·chrome bord and pillar mines in South Africa Some of these falls resulted in fatalities It appears that most favoured approach has been to use the rule of thumb method where the length of support is designed by specifying a support height based on a 95% fall out height for different ground conditions or ground control areas
·x Bord and pillar mining also known as room and pillar mining x Surface mining operations x Open cut mining strip mining o Using draglines o Using truck and shovels and o Using a combination of above integrated mining systems Mining Methods 4 x Highwall mining
