煤矿科技英语

1、煤矿科技英语5. BRIEF INTRODUCTION TO COAL MINING 2006年8月1日 11:50:0Coal mining 1 is the removal of coal from the ground. The mining method employed to extract the coal depends on the following criteria: a. seam thickness 2, b. the overburden thickness, c. the ease of removal of the overburden, d. the ease

2、with which a shaft 3 can be sunk to reach the coal seam, e. the amount of coal extracted relative to the amount that cannot be removed, and f. the market demand for the coal.The two types of mining methods are surface mining 4 and underground mining 5. In surface mining, the layers of rock or soil o

3、verlying a coal seam are first removed after which the coal is extracted from the exposed seam. In underground mining, a shaft is dug to reach the coal seam. Currently, underground mining accounts for approximately 60 percent of the world recovery of coal.5-1 Surface Mining Surface mining is used to

4、 reach coal reserves that are too shallow to be reached by other mining methods. Types of surface mining include open-pit mining 6, drift mining 7, slope mining 8, contour mining 9, and auger mining 10.A. Open-pit MiningIn open-pit mining, or strip mining, earth-moving equipment is used to remove th

5、e rocky overburden and then huge mechanical shovels 11 scoop 12 coal up from the underlying deposit. The modern coal industry has developed some of the largest industrial equipment ever made, including shovels capable of holding 290 metric tons of coal.To reach the coal, bulldozers 13 clear the vege

6、tation and soil. Depending on the hardness and depth of the exposed sedimentary rocks, these rocky layers may be shattered with explosives. To do this, workers drill blast holes 14 into the overlying sedimentary rock, fill these holes with explosives 15, and then blast the overburden to fracture the

7、 rock. Once the broken rock is removed, coal is shoveled from the underlying deposit into giant earth-moving trucks 16 for transport 17.B. Drift MiningDrift mining is used when a horizontal seam 18 of coal emerges at the surface on the side of a hill or mountain, and the opening 19 into the mine can

8、 be made directly into the coal seam. This type of mining is generally the easiest and most economical type because excavation through rock is not necessary. If coal is available in this manner, it is likely to be mined.C. Slope Mining Slope mining occurs when an inclined opening is used to tap the

9、coal seam (or seams). A slope mine may follow the coal seam if the seam is inclined and exposed to the surface, or the slope may be driven through rock strata overlying the coal to reach a seam. Coal transportation from a slope mine can be accomplished by conveyor 20 or by track haulage 21 (using a

10、trolley locomotive 22 if the grade is not severe) or by pulling mine cars 23 up the slope using an electric hoist 24 and steel rope 25 if the grade is steep. The most common practice is to use a belt conveyor.D. Contour Mining Contour mining occurs on hilly or mountainous terrain, where workers use

11、excavation equipment to cut into the hillside along its contour to remove the overlying rock and then mine the coal. The depth to which workers must cut into the hillside depends on factors such as hill slope and coal bed thickness. E. Auger Mining Auger mining is frequently employed in open-pit min

12、es where the thickness of the overburden is too great for open-pit mining to be cost-effective 26. Open-pit mining would require the lengthy and costly removal of the overburden, whereas auger mining is more efficient because it cuts through the overburden and removes the coal as it drills. In this

13、technique, the miners drill a series of horizontal holes into the coal bed with a large auger (drill) powered by a diesel or gasoline engine 27. These augers are typically about 60 m (200 ft) long and 0.6 to 2.1 m (2 to 7 ft) in diameter. As these enormous drills bore into the coal seam, they discha

14、rge coal like a wood drill producing wood shavings. Additional auger lengths are added as the cutting head of the auger penetrates farther into the coal. Penetration continues until the cutting head drifts into the top or bottom of the coal seam, into a previous hole, or until the maximum torque 28

15、(energy required to twist an object) of the auger is reached.F. Satellite Aids 29 to Surface Mining In the late 1990s some coal mining enterprises used technologies such as the global positioning system (GPS) 30 to help guide the positioning of mining equipment. Satellites operated by the United Sta

16、tes Air Force Space Command and leased to companies for commercial use track the position of mining equipment against a map of a mines topography 31. This map uses colors to distinguish soil that should be excavated, soil that should remain in place, and areas that should be filled in. The equipment

17、 driver observes this visual information 32 on a monitor 33 while operating the equipment. Some coal mining enterprises have used GPS to increase mining efficiency up to 30 percent. 52 Underground MiningUnderground, or deep, mining occurs when coal is extracted from a seam without removal of the ove

18、rlying strata. Miners build a shaft mine that enters the earth through a vertical opening and descends from the surface to the coal seam. In the mine, the coal is extracted from the seam by various methods, including conventional mining 34, continuous mining 35, longwall mining 36, and room-and-pill

19、ar mining 37. A. Conventional MiningConventional mining, also called cyclic mining, involves a sequence of operations that proceed in the following order: a. supporting the roof 38, b. ventilation 39, c. cutting 40, d. drilling 41, e. blasting 42, f. coal removal 43, and g. loading 44. First, miners

20、 make the roof above the seam safe and stable by timbering 45 or by roof bolting 46, processes intended to prevent the roof from collapsing 47. At the same time, they create ventilation openings so that dangerous gases 48 can escape and fresh air can reach the miners. Then one or more slots 49a few

21、centimeters wide and extending for several meters into the coalare cut along the face of the coal seam, also known as the wall face, by a large, mobile cutting machine 50. The cut, or slot, provides easy access to the face and facilitates the breaking up of the coal, which is usually blasted from th

22、e seam by explosives known as permissible explosives. This type of explosive produces an almost flame-free explosion 51 and markedly reduces the amount of noxious fumes 52 in comparison with conventional explosives. The coal may then be transported by rubber-tired electric vehicles (shuttle cars) 53

23、 or by chain (or belt) conveyor systems 54.B. Continuous MiningContinuous mining involves the use of a single machine known as a continuous miner that breaks the coal mechanically and loads it for transport. This mobile machine 55 has a series of metal-studded rotating drums 56 that gouge coal from

24、the face of the coal seam. One continuous miner can mechanically break apart about 1.8 metric tons of coal per hour. Roof support is then installed, ventilation is advanced, and the coalface 57 is ready for the next cycle. The method used to transport the coal requires the installation of mobile bel

25、t conveyors.C. Longwall Mining The longwall mining system uses a remote-controlled 58 self-advancing support 59 in which large blocks of coal are completely extracted in a continuous operation. Hydraulic or self-advancing jacks 60, known as chocks 61, support the roof at the immediate face as the co

26、al is removed. As the face advances 62, the roof is allowed to collapse behind the remote-controlled, roof-building machinery 63. Miners then remove the fallen coal. Coal recovery 64 is comparable to that attainable with the conventional or continuous mining systems. D. Room-and-Pillar MiningRoom-an

27、d-pillar mining is a means of developing a coalface and, at the same time, retaining supports for the roof. With this technique, rooms are developed from large, parallel tunnels driven into the solid coal 65, and the intervening pillars 66 of coal are used to support the roof. The percentage of coal

28、 recovered from a seam depends on the number and size of protective pillars of coal thought necessary to support the roof safely. Workers may remove some coal pillars just before closing the mine.NOTES TO THE TEXT1 coal mining：采煤 2 seam thickness：煤层厚度3 shaft：立井4 surface mining：地面开采 5 underground min

29、ing：地下开采6 open-pit mining：露天矿开采 7 drift mining：平峒开采 8 slope mining：斜井开采 9 contour mining：台阶开采 10 auger mining：螺旋钻开采 11 mechanical shovels：机械铲 12 scoop：铲斗 13 bulldozer：推土机 14 blast holes：炮眼 15 explosives：炸药 16 earth-moving trucks：地面移动卡车 17 transport：运输，输送 18 horizontal seam：水平煤层 19 opening：坑道20 conve

30、yor：输送机 21 track haulage：轨道运输 22 trolley locomotive：架线式电机车 23 mine cars：矿车 24 electric hoist：电动提升机 25 steel rope：钢丝绳26 cost-effective：成本效果 27 gasoline engine：汽油发动机 28 maximum torque：最大扭矩 29 satellite aids：卫星辅助 30 global positioning system (GPS)：地球定位系统31 topography：地形 32 visual information：可视信息 33 mo

31、nitor：监控器，监视器34 conventional mining：传统式开采法 35 continuous mining：连续（采煤机）式开采法 36 longwall mining：长壁式开采法37 room-and-pillar mining：房柱式开采法38 supporting the roof：支护顶板39 ventilation：通风 40 cutting：截割，掏槽 41 drilling：钻眼 42 blasting：爆破，放炮43 coal removal：出媒 44 loading：装载45 timbering：木支架46 roof bolting：顶板锚杆支护47

32、collapsing：垮落，崩落48 dangerous gases：危险气体 49 slot：槽，沟50 mobile cutting machine：移动式截媒机 51 flame-free explosion：无焰爆破 52 noxious fumes：有毒烟雾 53 rubber-tired electric vehicles (shuttle cars)：电动胶轮车（梭车） 54 chain (or belt) conveyor system：刮板（胶带）输送机系统55 mobile machine：移动式机器 56 metal-studded rotating drums：金属双头

33、螺栓式旋转滚筒 57 coalface：采煤工作面 58 remote-controlled：遥控的 59 self-advancing support：自移式支架 60 hydraulic or self-advancing jacks：液压或自移式千斤顶 61 chocks：垛式（液压）支架62 face advances：工作面推进63 roof-building machinery：筑顶机械64 coal recovery：媒炭回收率 65 solid coal：实体煤 66 intervening pillars：煤房间的煤柱GLOSSARY OF MINING TERMS12006

34、年8月2日 17:14:0AAbutment - In coal mining, (1) the weight of the rocks above a narrow roadway is transferred to the solid coal along the sides, which act as abutments of the arch of strata spanning the roadway; and (2) the weight of the rocks over a longwall face is transferred to the front abutment,

35、that is, the solid coal ahead of the face and the back abutment, that is, the settled packs behind the face.Acid deposition or acid rain Refers loosely to a mixture of wet and dry deposition (deposited material) from the atmosphere containing higher than normal amount of nitric and sulfuric acids. T

36、he precursors or chemical forerunners of acid rain formation result from both natural sources, such as volcanoes and decaying vegetation, and man-made sources, primarily emissions of sulfur and nitrogen oxides resulting from fossil fuel combustion.Acid mine water - Mine water that contains free sulf

37、uric acid, mainly due to the weathering of iron pyrites.Active workings - Any place in a mine where miners are normally required to work or travel and which are ventilated and inspected regularly.Adit - A nearly horizontal passage from the surface by which a mine is entered and dewatered. A blind ho

38、rizontal opening into a mountain, with only one entrance.Advance - Mining in the same direction, or order of sequence; first mining as distinguished from retreat.Air split - The division of a current of air into two or more parts.Airway - Any passage through which air is carried. Also known as an ai

39、r course.Anemometer - Instrument for measuring air velocity.Angle of dip - The angle at which strata or mineral deposits are inclined to the horizontal plane.Angle of draw - In coal mine subsidence, this angle is assumed to bisect the angle between the vertical and the angle of repose of the materia

40、l and is 20 for flat seams. For dipping seams, the angle of break increases, being 35.8 from the vertical for a 40 dip. The main break occurs over the seam at an angle from the vertical equal to half the dip.Angle of repose - The maximum angle from horizontal at which a given material will rest on a

41、 given surface without sliding or rolling.Anticline - An upward fold or arch of rock strata.Aquifer - A water-bearing bed of porous rock, often sandstone.Arching - Fracture processes around a mine opening, leading to stabilization by an arching effect.Area (of an airway) - Average width multiplied b

42、y average height of airway, expressed in square feet.Auger - A rotary drill that uses a screw device to penetrate, break, and then transport the drilled material (coal). Auxiliary operations - All activities supportive of but not contributing directly to mining.Auxiliary ventilation - Portion of mai

43、n ventilating current directed to face of dead end entry by means of an auxiliary fan and tubing.Azimuth - A surveying term that references the angle measured clockwise from any meridian (the established line of reference). The bearing is used to designate direction. The bearing of a line is the acu

44、te horizontal angle between the meridian and the line. BBack - The roof or upper part in any underground mining cavity.Backfill Mine waste or rock used to support the roof after coal removal.Barren - Said of rock or vein material containing no minerals of value, and of strata without coal, or contai

45、ning coal in seams too thin to be workable.Barricading - Enclosing part of a mine to prevent inflow of noxious gasses from a mine fire or an explosion.Barrier - Something that bars or keeps out. Barrier pillars are solid blocks of coal left between two mines or sections of a mine to prevent accident

46、s due to inrushes of water, gas, or from explosions or a mine fire.Beam - A bar or straight girder used to support a span of roof between two support props or walls.Beam building - The creation of a strong, inflexible beam by bolting or otherwise fastening together several weaker layers. In coal min

47、ing this is the intended basis for roof bolting.Bearing A surveying term used to designate direction. The bearing of a line is the acute horizontal angle between the meridian and the line. The meridian is an established line of reference. Azimuths are angles measured clockwise from any meridian.Bear

48、ing plate - A plate used to distribute a given load. In roof bolting, the plate used between the bolt head and the roof.Bed - A stratum of coal or other sedimentary deposit. Belt conveyor - A looped belt on which coal or other materials can be carried and which is generally constructed of flame-resi

49、stant material or of reinforced rubber or rubber-like substance.Belt idler - A roller, usually of cylindrical shape, which is supported on a frame and which, in turn, supports or guides a conveyor belt. Idlers are not powered but turn by contact with the moving belt.Belt take-up - A belt pulley, gen

50、erally under a conveyor belt and inby the drive pulley, kept under strong tension parallel to the belt line. Its purpose is to automatically compensate for any slack in the belting created by start-up, etc.Bench - One of to or more divisions of a coal seam separated by slate or formed by the process

51、 of cutting the coal.Beneficiation - The treatment of mined material, making it more concentrated or richer. Berm - A pile or mound of material capable of restraining a vehicle.Binder - A streak of impurity in a coal seam.Bit - The hardened and strengthened device at the end of a drill rod that tran

52、smits the energy of breakage to the rock. The size of the bit determines the size of the hole. A bit may be either detachable from or integral with its supporting drill rod.Bituminous coal A middle rank coal (between subbituminous and anthracite) formed by additional pressure and heat on lignite. Us

53、ually has a high Btu value and may be referred to as soft coal.Black damp - A term generally applied to carbon dioxide. Strictly speaking, it is a mixture of carbon dioxide and nitrogen. It is also applied to an atmosphere depleted of oxygen, rather than having an excess of carbon dioxide.Blasting a

54、gent - Any material consisting of a mixture of a fuel and an oxidizer. Blasting cap - A detonator containing a charge of detonating compound, which is ignited by electric current or the spark of a fuse. Used for detonating explosives.Blasting circuit - Electric circuits used to fire electric detonat

55、ors or to ignite an igniter cord by means of an electric starter.Bleeder or bleeder entries - Special air courses developed and maintained as part of the mine ventilation system and designed to continuously move air-methane mixtures emitted by the gob or at the active face away from the active worki

56、ngs and into mine-return air courses. Alt: Exhaust ventilation lateral.Bolt torque - The turning force in foot-pounds applied to a roof bolt to achieve an installed tension.Borehole - Any deep or long drill-hole, usually associated with a diamond drill.Bottom - Floor or underlying surface of an unde

57、rground excavation.Boss - Any member of the managerial ranks who is directly in charge of miners (e.g., shift-boss, face-boss, fire-boss, etc.).Box-type magazine - A small, portable magazine used to store limited quantities of explosives or detonators for short periods of time at locations in the mine which are convenient to the blasting sites at which they will be used.Brattice or brattice cloth - Fire-resistant fabric or plastic partition used in a mine passage to confine the air and force it into the working place. Also termed line brattice, line canvas, or line curtain.Break line - The