COAL MINING TECHNOLOGY - E-library WCL
COAL MINING TECHNOLOGYA Presentation byMANOJ KUMAR SINGHManager(IE), NCL-HQ, Singrauli(MP)-486 889E-mail : mks ie@nclhq.nic.in, M-9993875526
MINING TECHNOLOGYOPENCAST MINING TECHNOLOGY Shovel-Dumper Dragline Surface MinerUNDERGROUND MINING TECHNOLOGY Bord & Pillar Side Discharge Loader(SDL) Load Haul Dump(LHD) Continuous Miner Longwall Shortwall MiningOTHER MINING TECHNOLOGY Highwall Mining2
UG MINING TECHNOLOGYUG MINING METHOD BORD & PILLAR LONGWALLINTERMITTENT MINING METHOD SIDE DISCHARGE LOADER (SDL) LOAD HAUL DUMP (LHD)MASS PRODUCTION TECHNOLOGY CONTINUOUS MINER LONGWALL3
UG MINING METHODSBORD & PILLAR Method Coal deposits are mined by cutting anetwork of ‘roads’ into the coal seam andleaving behind ‘pillars’ of coal to supportthe roof of the mine.LONGWALL Method It involves the full extraction of coal from asection of the seam or ‘face’ usingmechanical shearers to cut and remove thecoal at the face. Self advancing Roof Supports are used totemporarily hold up the roof while coal isextracted.4
BORD & PILLAR Mining Bord & Pillar is the traditional miningmethod used in India. It is employed where geo-mining conditionsare complex. Coal is removed from the coal faces initiallyby developing a set of galleries leavingpillars in between to support the roof. Thereafter, the pillars are extracted by depillaring. Initially only 30% of the coal can beextracted, while most of the remaining coalis extracted during de-pillaring.5
BORD & PILLAR METHOD Coal deposits are mined by cutting a network of‘roads’ into the coal seam & leaving behind‘pillars’ of coal to support the roof of the mine. These pillars can be up to 40% of the total coal inthe seam – although this coal can sometimes berecovered at a later stage by ‘retreat mining’. Theroof is then allowed to collapse and the mine isabandoned. Smaller deposits can have Manual loading &intermediate technologies with continuous minersor LHDs & SDLs. Mechanisation in Bord and pillar has limitations ofgradients. Seams steeper than 12 (1 in 5 ) are not6suitable.
Road
BORD & PILLAR MININGSEMI-MECHANISED METHOD Currently, most of CIL mines using Bord & Pillar removecoal from the face by blasting & deploy SDL or LHD forloading and transportation of coal in the active miningareas. Coal transportation to surface is either by a series of beltconveyors or rope haulage drawn coal tubs. This method requires less capital investment but is morelabour intensive.CONTINUOUS MINING METHOD In many of CIL new underground mines, bord & pillarmining is carried out using Continuous Miner methodwhere geo-mining conditions permit. The coal is mined by a continuous miner unit & loaded toshuttle cars which deliver coal to feeder breaker linkedwith belt conveyor for onward transportation to surface. 8
LONGWALL MINING Longwall is a fully mechanised undergroundmining method where the roof at the coal face issupported by self-advancing powered supports &the coal is mined by a shearer. Armoured face conveyor & stage loader-crusherare used for transportation of coal at the Longwallface. A series of belt conveyors is used to transport coalto the surface. When the mining of a Longwall panel has beencompleted, the equipment is moved to a newLongwall face. The key characteristics of Longwall Mining includehigh productivity, high recovery rate and safety &9reliability.
LONGWALL MINING It involves the full extraction of coal from a section ofthe seam or ‘face’ using mechanical shearers to cutand remove the coal at the face. The coal ‘face’ can vary in length from 100 to 350metres. Self advancing Roof Supports (SARS) are used(hydraulically-powered supports) to temporarily holdup the roof while coal is extracted. When coal has been extracted from the area, the roofis allowed to collapse. Over 75% of the coal in the deposit can be extractedfrom panels of coal that can extend 3 km through thecoal seam. Large reserve & uniform deposit are mined byLongwall mining. It is a bulk production but capital intensive technology.10
POWERED SUPPORT LONGWALL
POWER SUPPORTpackageLONGWALL For EXTRACTION Shearer Powered support Armoured Face Conveyor Stage loader - crusher Power pack For DEVELOPMENT Continuous miner package or Road header package-1- 1 set-1-1-112
SELECTION OF UG METHODManual In all grdientsSDL Where the gradient is 1 in 5 (120)LHD Where the gradient is 1 in 6 (100)Continuous Miner Where the gradient is 1 in 8 (70)Longwall Where the property is devoid of fault.13
MAJOR UG EQUIPMENTSWINNING & LOADING DRILLING MACHINES (Hand held, Tyre/ crawler mounted) ROAD HEADER SHEARER CONTINUOUS MINER SIDE DISCHARGE LOADER(SDL) LOAD HAUL DUMP(LHD)TRANSPORTATION CONVEYORS (Belt conveyors, Chain conveyors) HAULAGES (Direct haulage, Endless haulage, Main & tailhaulage) WINDING SYSTEMS (Drum winder, Friction/koepe winder) MAN RIDING SYSTEMS SHUTTLE CARS/RAM CARS LOCOS14
SIDE DISCHARGE LOADER (SDL)
LOAD HAUL DUMP (LHD)
ROAD HEADER
CONTINUOUS MINER
CONTINUOUS MINER package For DEVELOPMENT & EXTRACTION Continuous miner*- 1 no. Shuttle cars- 2 no. Twin/ Quad bolter*- 1 no. Feeder breaker- 1 no. Power pack- 1 no. Mobile goaf edge support (Optional) -2 (* In some package both the machinesare integrated into one)19
SHUTTLE CAR
ROOF BOLTER
SHEARER
POWERED SUPPORT
Support UG EquipmentsVENTILATION FANSPUMPSSAFETY RELATED EQUIPMENTS Self contained self rescuers Gas monitoring devicesSHOT FIRING EQUIPMENTSUPPORTS Shield type hydraulic power support Individual hydraulic/friction/screw supportsMONITORING DEVICESROOF BOLTER Hand held Crawler mountedCOMMUNICATION SYSTEMS Conventional wire based From surface to UG- wireless and from UG to surface –Combination of wire and microwave24
U/G MECHANISATION IN CIL (1st.April 652525
PRODUCTIVITY IN UGSIDE DISCHARGE LOADER 110 tonnes per day (For a 5-heading districthaving 3 SDLs)LOAD HAUL DUMPER 200 tonnes per day (For a 5-heading districthaving 3 LHDs)CONTINUOUS MINER 1,200 to 2,400 tonnes per day (dependingon the seam thickness)POWERED SUPPORT LONGWALL 3,280 tonnes per day onwards (1 MTY)26
TO ENHANCE UG COAL PRODUCTION IN INDIAIntroduction of mass productiontechnology Longwall Continuous Miner (CM) Low Capacity Continuous Miner (LCCM)Application of UDM, SDL & LHD Application of Universal Drilling Machine(UDM) with SDLs and LHDs for improvingrate of output in B&P method of working.27
ECONOMICS OF UG MINING UG mining, by and large remains, a losingproposition In the existing pricing mechanism it is difficult torecover the higher cost of UG production The average cost of production from UG miningwas Rs. 1,819 per tonne (2005-06) of coal The coking coal & good grade deposits are largelyamenable to UG mining In future UG mining will be done from greaterdepths, further increasing the cost of production In this scenario, the customer should be ready topay higher price.28
ENVIRONMENTAL & SAFETY ISSUES During UG mining, the inherent dangers of roof & sidefall, fire, explosion, noxious gases, water inundation etc.are to be dealt with. Roof & side fall remains the most common cause of UGmine accidents. Switching to mass production technology will reduce theno. of accidents due to strata control and those relatedwith the handling of explosives. Extensive R&D work is being done to limit accidents dueto roof fall. One such major R&D work for detecting ofearly bed separation and hidden slips accompaniedwith audible warning is going on in IIT Kharagpur Use of bolting techniques will reduce the chances of29accidents in semi-mechanised mines
KEY SAFETY ISSUES IN COAL MININGHIGHWALL AND LOW WALL STABILITYINTERNAL AND EXTERNAL DUMP STABILITYSTABLE PROFILE OF DRAGLINE DUMPSSAFETY IN MINING LAYOUTSSAFETY IN BLASTING OPERATIONSSAFETY RELATED TO MINING OPERATIONSSAFETY RELATED TO MINING EQUIPMENT30
OC MINING TECHNOLOGYDISCONTINUOUS MINING Shovel-Dumper Mining Dragline Mining Combined Mining Surface MinerCONTINUOUS MINING Bucket Wheel Excavator (BWE) Conveyor System Spreaders Tripper CarsHYBRID MINING In-Pit Crushing & Conveying System31
KEY DRIVERS FOR CHANGE INTECHNOLOGY Surge in demand Cost competitiveness Quality improvement Ensuring higher safety in UG & OC mines Increase in level of mechanisation in UG &OC operations Environmental issues Improving man & machine productivity Improving percentage of extraction in UGmines32
SHOVEL-DUMPER MINING It is the most sought after technologyin opencast mining due to its inherentflexibility of operation. It can be used more or less in all typesof deposits from flatter to highly steep,softer to hard rocks etc. In future, in addition to shovels, coalindustry may go for high capacitywheel loaders (tyre mounted) also.33
SHOVEL-DUMPER COMBINATIONS10cum Shovel 100T Dumper17 to 20cum Shovel 100T/150TDumper20 to 22cum Shovel 150T Dumper25 to 28cum Shovel 150T/240TDumper34cum Shovel 240T/360T/400TDumper50cum Shovel 360T/400T Dumper34
ROPE SHOVELS Low operating & maintenance cost of rope shovels makethem ideally suited for stripping overburden in largequantities. 42 cum bucket capacity rope shovel at Gevra OCP (SECL)is the biggest rope shovels deployed in CIL & India. Internationally the largest Rope Shovel deployed is of63cum bucket capacity.HYDRAULIC SHOVELS Hydraulic Shovels are ideally suited for selective miningand for operation in low bank heights in medium hardstrata conditions. Currently, 18 cum bucket capacity hydraulic shovels arethe biggest hydraulic shovels deployed in CIL & India. The largest Hydraulic Shovels deployed in the world are 50 cum bucket capacity front end shovels.35
ROPE SHOVEL
HYDRAULIC SHOVEL
HYDRAULIC BACKHOE SHOVEL
WHEEL LOADERWHEELLOADERLOADING INA REARDUMP TRUCK
DUMPERS Dumpers offer the most flexible meansof transporting the mined coal oroverburden to the designated areas. Currently, 240 T capacity rear dumpersat Gevra OCP (SECL) are the biggestDumpers deployed in CIL & India. The largest dumpers deployedinternationally are 400T at present.40
DRAGLINE MINING Dragline mining is the most cost effectivetechnology for the bedded deposits and is thefirst-choice technology for large opencastmining. Draglines do not require dumpers for transportof the mine waste as the overburden strippedby the draglines is directly cast into de-coaledpit. The largest dragline operating in India is 30cum bucket capacity & boom length of 96 m(Bishrampur OCP, SECL). Internationally, the largest dragline size is 76 to122cum bucket capacity with 132 to 76mboom length.41
DRAGLINE
BUCKET WHEEL EXCAVATOR (BWE) Applicable in flatter deposits with relatively softerstrata which do not require blasting e.g. Lignite. The BWE is a Continuous Mining Technology andworks in conjunction with Conveyor belts &Spreaders. The current deployment of BWE is limited to 350Lt, 500 Lt, 700 Lt & 1,400 Lt size units. It is expected that 2,800 Lt. BWE will be deployedin future. Conveyor systems of 1,600 mm, 2,000mm & 2,400mm are in operation in the mines of NLC &GMDC. It is likely that in future the size of conveyors willbe 3,000 mm.43
BUCKET WHEEL EXCAVATOR (BWE)
CONTINUOUS MINING WITH BWE
IN-PIT CRUSHING & CONVEYING In pit crushing of coal is generally found to beeconomical in high capacity opencast mineswhere reasonable lead distance and lifts areinvolved. This technology is, however, associated withextremely high Capital & Operating costs. Mobile in-pit crushing and conveyingtechnology for coal is in operation at thePiparwar OCP (CCL) Shiftable in-pit crushing & conveying ofoverburden (OB) is in operation atRamagundem-II Mine (SCCL)46
IN-PIT CRUSHING & CONVEYING
SURFACE MINER It finds its natural applications in projectswhere drilling and blasting is prohibited orwhere selective overburden is required. Some of the opencast coal mines of MCL (CIL)are presently using surface miners oncontractual basis for extraction of banded coalseams. Presently surface miner is used as cuttingmachine only and pay loader has been addedfor loading the coal into the tipping trucks. Tripper cars and Spreader systems of 11,000TPH & 20,000 TPH are already in operation inNLC48
ADVANTAGESMINEROFSURFACE Less coal loss and dilution. Improved coal recovery especially inareas sensitive to blasting. Less stress and strain on trucks due tominimum impact of the excavatedmaterial. Primary crushing and fragmentation ofcoal. Reduced capacity requirements forcoal washing/preparation plants.49
SURFACE MINER IN OB
SURFACE MINER IN COAL
SPREADER
HIGHWALL MINING Highwall/Trench mining is a remote controlledmining method which extracts coal from the base ofan exposed highwall via a series of parallel entriesdriven to a significant depth within the coal horizon. It allows recovery of coal from surface pits that havereached final highwall position, or in areas wherecoal has become sterilized, e.g. in-service corridors. A trench of suitable dimension is dug centrallywhere Highwall is not available, and paralleldrivages are made in both directions along dip aswell as along rise. The technology may have wide application inextracting reserves of thin seams (0.8m to 1.5m). The method is under use at Sharda Project (SECL) 53
HIGHWALL MINER
Current OC Equipment Sizes in India DRAGLINE: 24 to 30 cum/96 to 71m ROPE SHOVEL: 42cum (Gevra-SECL) HYDRAULIC SHOVEL : 18cum DUMPER: 240T (Gevra-SECL) Bucket Wheel Excavator : upto 1,400 Lt Tripper Car & Spreader : upto 20,000 TPH In-pit crushing & conveying(Coal) : 2,800TPH(Piparwar-CCL) In-pit crushing & conveying(OB) : 3,500TPH(Ramagundam-II-SCCL) Surface Miner: 750TPH Drills : upto 381mm, Dozers : upto 850hp Motor Graders: upto 280hp55 Front End Loaders: upto 11.50cum
HEMM POPULATION IN CIL (1st.April 03-MCL570337101574CIL406913,260958673456
Coal deposits are mined by cutting a network of 'roads' into the coal seam & leaving behind 'pillars' of coal to support the roof of the mine. These pillars can be up to 40% of the total coal in the seam - although this coal can sometimes be recovered at a later stage by 'retreat mining'.The roof is then allowed to collapse and the mine is
Our main source of coal comes from a coal mine near Butler, Missouri. A stock pile of coal for unexpected emergencies is maintained at Blue Valley. A 90-day supply of coal consists of 45,000 tons of coal. Coal Feeders Feeding coal from the bunkers to the pulverizers is the purpose of the coal feeders. The pulverizers grind the coal into a fine .
as.edu / n e Resources -Coal 1 Based on -The Coal Resource by World Coal Institute 2005.-The Coal Resource Base, Chapter 2 of Producing Liquid Fuels from Coal by J.T. Bartis, F. Camm and D.S. Ortiz. Published by RAND 2008. ISBN: 978--8330-4511-9. -The Role of Coal in Energy Growth and CO2 Emissions, Chapter 2 of The Future of Coal, an Interdisciplinary MIT Study, 2007.
Coal Mining and Production 342 Loads Per Unit of Production* Parameter Surface mining (t/1000t coal produced) Underground mining (t/1000t coal produced) Mining Techniques Contour Area Conventional Longwall Liquid effluents 0.24 1.2 1 1.6 Solid waste 10 10 3 5 Dust 0.
IEA Clean Coal Centre – New regulatory trends: effect on coal-fired power plant and coal demand 4 . Abstract . This review presents the recent regulatory trends, practices and developments, in major coal producing and consuming countries, which are affecting and may influence future demand for coal and coal-fired power generation.
The Lower Kittanning coal bed assessment only includes maps showing its areal extent and geochemical parameters and a history of the mining of the coal bed. Pittsburgh Coal Bed The results of the Pittsburgh coal bed assessment (North-ern and Central Appalachian Basin Coal Regions Assessment Team, 2001; Tewalt, Ruppert, Bragg, Carlton, and others,Author: Michael H. Trippi, Leslie F. Ruppert, Robert C. Milici, Scott A. Kinney
2 School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou 221116, China * Correspondence: . due to coal mining on regional ecological environment as well as on human or animal health [45-47]; (3) impact of coal mining on ecosystem services [48]; (4) mining impact on land use in general [49];
Coal is comprised of organic and inorganic (mineral) assemblages. . do we understand coal? (CCT, advanced applications) ORGANIC PETROLOGY FINDS RELEVANCE IN GEOLOGY, METALLURGY, CHEMICAL ENGINEERING, COAL SUSTAINABILITY ACROSS THE COAL VALUE-CHAIN . LIGHT WEIGHT COMPOSITE MATERIALS Underground coal gasification Many additional uses: Paper .
Abstract . The aim of this paper is to build on the Pragmatic Stochastic Reserving Working Party’s first paper (Carrato, et al., 2016) and present an overview of stochastic reserving used with a one-year view of
