采矿工程英语

Theexactdateofman’sfirstuseofcoalislostinantiquity.Thediscoverythatcertainblackrockwouldburnwasundoubtedlyaccidentalandprobablyoccurredindependentlyandmanytimesintheworldoverthousandsofyears.Itisquitelikelythattheseindependentdiscoveriesweremadewhenprimitivemanchancedtobuildcampfiresonexposedledgesofablackrock,thenwasamazedwhenitcaughtfire.TheChineserecordedtheuseofcoal1,100yearsbeforetheChristianEra.InWales,thereisevidencethattheBronzeAgepeopleusedcoalforfuneralpyres,anditisknownthattheRomansusedthisfuel.Thereareotherancientreferences.However,practicalandconsistentuseofcoalseemstodatetoEnglandintheMiddleAges.However,thefirstrecordeddiscoveryofcoal,inwhatisnowUS,wasbyFrenchexplorers,whoreportedanoutcropexposureontheIllinoisRiverin1679.ThefirstrecordedactualusagewasinVirginiain1702tousecoalforaFrenchsettler’sforge.Earliestrecordedcommercialminingwasin1750,fromtheJamesRivercoalfieldnearRichmond,VA,adepositnowabandoned.Besideslocalconsumptionfromthisfield,shipmentsweremadetoPhiladelphia,NewYork,andBoston.hewedbyhandfromthesolidbedbyuseofpickandbarshoveledintobaskets,boxes,orwheelbarrowsanddraggedbymen,orwomentothefootofashaft(竖井)Later,carsweredevelopedbutstilldrawnoverwoodplankbyhumansAstimewenton,ironstraps,therails,wereusedforthecarswhilemules,ponies,orhorsesdidthepullingGradually,blackpowderwasintroducedtoblastdownthecoal,butundercutting,sidecutting,anddrillingwerestilldonebyhand.Duringthelate1700sand1800s,anumberofbasicdevelopmentsgreatlyaidedtheminingofcoal.firststeamenginepumpwaterfromcoalminesgodeeperfirstrailtransportationfirststeamlocomotivefirstelectriclocomotiveundergroundusePunchingmachinesandchain-typecuttersforunderminingthecoalseam.LongwallminingwasusedhereandthereintheUSuntilabout1910.Noncompetitivewithroom-and-pillarmethodsinthickerseamsDominantinEuropeandAsiabecauseofthincoalanddepthofcoverDuringWorldWallII,theGermansdevelopedthelongwallscraper（铲土机）forcontinuousloadingontoachainconveyor（传送机）attheface.Thiswasfollowedbyvarioustypesofshearingmachines（剪切机）developedinseveralcountries.However,themostimportantdevelopmentwasinhydraulic,self-propelledroofjacksandchocksthatgreatlyreducedthemanpowerformerlyrequiredtosetandresetindividualjacksandtobuildcribsbyhand.Surfacemining(地表采矿)wastheearliestmethodofextractingcoal.Itconsistedofrecoveringcoalexposedinstreambedsandvisibleoutcropswithzerotoafewfeetofloosedirtcover.Underdeepercoverandunderrockthecheapestmethod-infacttheonlymeansofrecoveryatfirst-wasbyundergroundmining,sosurfacedevelopmentswereinsignificantuntilabout1910,although,hereandthere,slipandcartscrapersdrawnbymuleswereusedtoaverysmallextent.FormfromaccumulationsofplantmaterialGeologicalConditions:(1)developoncontinentalinteriorareasrelativelyelevatedabovesealevel(2)forminlowcoastalareasclosetosealevel.Inbothtypesofareas,peatformationrequiresthatgrowthofvegetationexceedthatofdecayandthattheplantmaterialbeallowedtoaccumulateandnotberemovedbyerosion.Insummary,conditionsnecessaryforaccumulationofpeatthatcouldbesubsequentlyconvertedtocoalare:Swampormarsh（湿地）environmentandclimatefavorabletoplantgrowth.Somesubsidence(sinking)oftheareaduringaccumulationofvegetaldebris,orcompactionofdepositedplantmaterial,permittingfurtheraccumulation.Sufficientlywetconditionstopermitexclusionofairfrommuchofthevegetalmaterialbeforeitdecays,andsufficientlyrapidaccumulationtothwart（阻碍）bacterialaction,eveninwateroftheswamp.Acidityoftheswampwaternormallypreventsbacterialactionatafewinchesorafewfeetbelowthewaterlevelintheswamp.Proximitytotheseaorasubsidingareasothatvegetalmaterialcanbeburiedbysedimentswhenthesealevelrisesorthelandsubsides.Siteofaccumulationsuchthatremovalbyerosiondoesnotsubsequentlyoccur.Therankofthecoalbecameprogressivelyhigher,risingfromLignite（褐煤）Subbituminous（亚烟煤）Bituminous（烟煤）Semi-anthracite（半无烟煤）Anthracite（无烟煤）Meta-anthracite（高级炭化无烟煤）Thephysicalpropertiesareconcernedwiththecharacteristicsofcoalinitsnaturalstate,orpriortoitsenduseasafuel.Forexample,thehardnessandgrindabilityofcoaldeterminethemaintenancecostforcoalmining,handling,andpulverizing(磨粉)equipment;thespecificgravity（比重）ofcoalanditsassociatedmineralsdeterminesthecoalpreparationtechnique（选煤）usedinacleaningplant（选煤厂）aswellasthecapacityofcoalbins,bostsandsizeofcargos,andothercoalstoragefacilities.SpecificGravity(solid):TheratiooftheweightofacubicfootofthesolidtotheweightofacubicfootofwaterThespecificgravityofpurecoalhasbeenreportedtorangebetween1.23to1.72andincreaseswiththechangeinrankfromlignitetoanthracite.Theimpuritiesassociatedwiththecoal,suchasshale（页岩）,clays,sandstones,gypsum（石膏）,andcalcite（方解石）,rangeinspecificgravityfrom2.0toabout2.7,whilethespecificgravityofpyrite（黄铁矿）isabout5.0.Hardnessisatermrelatedtoacoal’sstructureandrank.Acoalisfirmorsoft-structureddependingonthecompositionandlocationofthecoalbed.Splintcoals（暗硬煤）arefirmerthanbrightcoals（光亮煤）.Highvolatile（挥发）coalsareusuallyfirmerthanlowvolatilecoals.Firmcoalsshipwellsincetheyresistbreakageandproducelessdegradationinhandling.Theabrasiveness（磨损）ofacoal,sofarasdamagetoequipmentisconcer