Bord and pillar mining Coal and coal mining Te Ara

This diagram shows the traditional method of bord and pillar mining. Miners first extracted coal along roadways or bords, while the coal in between the bords acted as pillars holding up the roof. Then the outer pillars were mined, leaving the roof to collapse in a controlled way as miners retreated to the exit.

Room and pillar mining Wikipedia

Room and pillar (variant of breast stoping), is a mining system in which the mined material is extracted across a horizontal plane, creating horizontal arrays of rooms and pillars. To do this, "rooms" of ore are dug out while "pillars" of untouched material are left to support the roof overburden.Calculating the size, shape, and position of pillars is a complicated procedure, and is an area of

typical bord and pillar mine plan ppt Mining

ROOM AND PILLAR PPT in Yemen Crusher South Africa. typical oreflow system in a bord and pillar coal mine. Room & Pillar Mine The PowerPoint PPT presentation: "2nd Pillar

EVALUATION OF BORD AND PILLAR MINING SYSTEM IN MCL

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

Bord-and-pillar mining explained Illawarra Mercury

Jun 01, 2017 Bord-and-pillar extraction is the older of the methods, and  The word “bord” is not a misspelling of “board”, but a mining term for an underground space or

Room and pillar mines, Mining Techniques, Underground

The room and pillar system is used in mining coal, iron and copper ores mainly when found as manto or blanket sediments, stone and aggregates, talc, soda ash and potash. The key to the winning room and pillar mining is opting the optimum pillar size. If the pillars are so small the mine will fall down.

bord and pillar coal mining grinding mill

bord and pillar coal mining Grinding Mill China. The room and pillar system is used in mining coal, iron and base metals ores, the size of both room and pillars are kept almost equal, while in Bord & Pillar, » Learn More. Bord and pillar mining Coal and coal mining Te Ara This diagram shows the traditional method of bord and pillar mining.

COAL PILLAR STRENGTH AND PRACTICAL COAL PILLAR

four failed pillars in two coal mines in southwestern Virginia (figure 2) and is in general agreement with many existing coal pillar design formulas at w/h < 5. FEM has also been used to evaluate the effect of in-seam and near-seam conditions, such as seam strength, rock partings, and weak floor rock, on pillar strength [Su and Hasenfus 1997]. On

Pillar design in coal mines SlideShare

May 06, 2011 All of these effects were minimal for slender pillars, but became much more pronounced once the w/h exceeded 5.The models also indicated that varying the uniaxial coal strength had almost no effect on pillar strength.Gale(1996,1998) observed that pillar strengths seemed to fall into two groups, using FLAC:• Strong roof and floor rock where

EVALUATION OF BORD AND PILLAR MINING SYSTEM IN

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

Room and pillar mines, Mining Techniques, Underground

The room and pillar system is used in mining coal, iron and copper ores mainly when found as manto or blanket sediments, stone and aggregates, talc, soda ash and potash. The key to the winning room and pillar mining is opting the optimum pillar size. If the pillars are so small the mine will fall down.

DESIGN OF SUPPORT SYSTEM FOR BORD AND PILLAR

1.1 Accident statistics of Indian underground coal mines 8 1.2 Present support system 9 CHAPTER 2 LITRATURE REVIEW 11 2.1 Rock load 11 2.2 Support estimation 11 2.3 2.3.1 2.3.2 Guidelines for drawing of support plans in bord & pillar Barton’s Q-system Bieniawski’s RMR system 11 12 13 2.4 CMRI-ISM Rock Mass Classification 13

Room and pillar en.wikipedia-on-ipfs

Room and pillar (variant of breast stoping), also called pillar and stall, [1] is a mining system in which the mined material is extracted across a horizontal plane, creating horizontal arrays of rooms and pillars. The ore is extracted in two phases. In the first, "pillars" of untouched material are left to support the roof overburden, and open areas or "rooms" are extracted underground; the

Room and pillar Infogalactic: the planetary knowledge core

Room and pillar (variant of breast stoping), also called pillar and stall, is a mining system in which the mined material is extracted across a horizontal plane, creating horizontal arrays of rooms and pillars. The ore is extracted in two phases. In the first, "pillars" of untouched material are left to support the roof overburden, and open areas or "rooms" are extracted underground; the

Pillar design incoalmines SAIMM

parameter that has considerable importance in bord-and-pillar mining isthe seam thickness. The influence ofthis parameter on the amount ofcoal lost inthe support pillars is shown in Fig. 2, which illustrates clearly how in a conventional bord-and-pillar system thecoallossesincrease with seamheight. From Figs. Iand2itfollowsthat theareaofapplica-

(PDF) Underground Mining Methods: Room and Pillar method

To minimise mining loses and also provide high safety conditions, proper dimensioning of pillars using geomechanics must be considered. [5] Figure 2 below illustrates typical pillar failure.

CHAIN PILLAR DESIGN Mining Science and Technology

p = pillar width (m) m = pillar height (m) NB: For Australian conditions a coefficient of 7.4 is used in place of 7.2. The load that is transferred onto a pillar is calculated by a simple emperical formula, the equation varies depending on the type of pillars and subsidence method being used: Single Line of square chain pillars

HAULAGE SYSTEM Mining Science and Technology

Bord & Pillar (15) Method (7) Traditional Pillar Extraction (2) Panel & Pillar Extraction (2) Modern Pillar Extraction (2) Equipment (5) Ground Control (1) Ventilation (2) Rock Bolting (20) Overview (2) Types of Bolts (2) Theories of Rock Bolting (8) Material for Installation (5) Videos (3) Coal Mine Outburst (16) Overview (2) Factors (3

Major Mines & Projects Kriel Mine

Board and pillar mining is typically used for flat or gently dipping bedded ores or coal seams. Once the coal seam has been accessed, the ore is mined utilising a regular grid of mining tunnels and involves progressively excavating panels into the coal seam whilst leaving behind pillars of coal to support the mine.

Mining simulation for room and pillar coal

Mining simulation for room and pillar coal operation by S.P. Pereira*, J.F.C.L. Costa†, P. Salvadoretti†, and J. Koppe† Synopsis The mechanized mining cycle using loaders and shuttle cars had its peak in terms of usage in the mining industry during 1950 through 1960. In Brazil, this system is still used at underground coal mines

UNDERGROUND COAL MINING: FACTORS, COST, AND

• Pillar sizes will generally range from 30 to 100 feet and have a rectangular configuration • Extraction Ratio is the ratio of coal removed compared to estimated in-place tonnage normal extraction ratio is from 35 to 55% retreat mining will result in extraction ratios of up to 70%

Introduction to Longwall Mining and Subsidence ver2

onto a belt conveyor, which carries the coal out of the mine. KEY 1. Drift for men and materials access 2. Shaft winder house 3. Bathhouse and administration building 4. Workshops 5. Coal preparation plant 6. Coal storage bins 7. Gas drainage system 8. Longwall face equipment 9. Coal seam 10. Continuous miner unit 11. Coal pillar 12

(PDF) CFD Modeling of Ventilation System of Bord & Pillar

Indian coal mining industry is now adopting bulk production technology, viz. Longwall technology and continuous miner (CM) in Bord & Pillar development along with mechanized transportation

Room and pillar en.wikipedia-on-ipfs

Room and pillar (variant of breast stoping), also called pillar and stall, [1] is a mining system in which the mined material is extracted across a horizontal plane, creating horizontal arrays of rooms and pillars. The ore is extracted in two phases. In the first, "pillars" of untouched material are left to support the roof overburden, and open areas or "rooms" are extracted underground; the

Mining simulation for room and pillar coal

Mining simulation for room and pillar coal operation by S.P. Pereira*, J.F.C.L. Costa†, P. Salvadoretti†, and J. Koppe† Synopsis The mechanized mining cycle using loaders and shuttle cars had its peak in terms of usage in the mining industry during 1950 through 1960. In Brazil, this system is still used at underground coal mines

Room and pillar Infogalactic: the planetary knowledge core

Room and pillar (variant of breast stoping), also called pillar and stall, is a mining system in which the mined material is extracted across a horizontal plane, creating horizontal arrays of rooms and pillars. The ore is extracted in two phases. In the first, "pillars" of untouched material are left to support the roof overburden, and open areas or "rooms" are extracted underground; the

Room and Pillar Mining Method SlideShare

Oct 22, 2014 Practical importance of the Room and pillars method: Method widely used in coal mines and non- carbon worldwide. In the 70s in the USA, over 50% of production (underground) coal came from this method. Currently, most of the production is still done by R & P. It is the mining method used in underground coal mining in southern Brazil. Prof. Dr.

ANALYSIS OF LONGWALL TAILGATE SERVICEABILITY

that used for pillars within bord-and-pillar operations. The bord-and-pillar approach is based on analysis of collapsed pillar cases from Australia and the Republic of South Africa [Salamon et al. 1996] and applies a factor of safety in relation to pillar collapse. This approach is inappropriate for a number of reasons when designing chain

(PDF) CFD Modeling of Ventilation System of Bord & Pillar

Indian coal mining industry is now adopting bulk production technology, viz. Longwall technology and continuous miner (CM) in Bord & Pillar development along with mechanized transportation

Pillar Extraction using Continuous Miners underground COAL

PILLAR EXTRACTION USING CONTINUOUS MINERS. Overview. Now that longwall equipment has been developed to a stage where it is able to cope with most conditions satisfactorily, longwall mining is the most widely used method of secondary extraction. However, there are still mines and occasions where longwall mining is not suitable e.g.

Introduction to Longwall Mining and Subsidence ver2

onto a belt conveyor, which carries the coal out of the mine. KEY 1. Drift for men and materials access 2. Shaft winder house 3. Bathhouse and administration building 4. Workshops 5. Coal preparation plant 6. Coal storage bins 7. Gas drainage system 8. Longwall face equipment 9. Coal seam 10. Continuous miner unit 11. Coal pillar 12

Estimation of rock load for junctions based on roof

Coal mine roadway junctions in bord and pillar mining, in particular, are more vulnerable to roof fall due to the excavation induced stresses as well as general stress loading pattern inherent to the typical cross section achieved in practice. Roof fall incidences are generally more in junctions of development galleries and a cause of concern as they provide access to faces in different

Major Mines & Projects Kriel Mine

Board and pillar mining is typically used for flat or gently dipping bedded ores or coal seams. Once the coal seam has been accessed, the ore is mined utilising a regular grid of mining tunnels and involves progressively excavating panels into the coal seam whilst leaving behind pillars of coal to support the mine.

Monitoring and management of subsidence induced by

Figure 2.2 An operating longwall coal mine face.. 5 Figure 2.3 Schematic cutaway view of a typical longwall coal mine .. 6 Figure 2.4 Plan layout of a typical longwall mine, also showing some bord and pillar

SOUTH AFRICAN COAL SECTOR REPORT Energy

South Africa. The most common technique is the ‘bord and pillar’ method, which accounts for just under half of total coal production (SACRM, 2011). This method is ideal for relatively shallow deposits where overlying rock pressure is low. Seams are mined leaving in situ coal pillars, which are big enough to support the roof indefinitely.

A comparative study between shuttle cars and battery haulers

Introduction to bord and pillar coal haulage In a typical underground mechanized bord and pillar mine section a Continuous Miner (CM) is used to cut the coal from the production face with a rooftogether bolting machine that installs permanent cemented roofbolts. Coal is loaded via the CM’s chain conveyor system

Ironbark No.1 Coal Mine Project Mining News

The Project will develop an underground coal mine which will utilise the longwall and bord and pillar mining techniques to extract the Leichhardt Seam. The Project includes the following components, as shown in Figure 2: • An underground coal mine with a production capacity of up to 6.0 Mtpa ROM coal utilising the longwall