专业英语.docx

专业英语.docx

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专业英语

河南理工大学自编教材

专业英语

安全工程专业

（学生用书）

高建良王云刚编

崔洪庆修改

安全科学与工程学院

2011年9月

contents

PartⅠMineVentilation1

LESSON1IntroductiontoMineVentilation1

LESSON2EnergyChangesinFluidFlow3

LESSON3FaceVentilation5

LESSON4MechanicalVentilation8

LESSON5MineVentilationSystems10

LESSON6FundamentalsofVentilationNetworkAnalysis12

PartⅡMineSafety15

LESSON7MineGases15

LESSON8CoalSeamMethane17

LESSON9OpenFires19

LESSON10SpontaneousCombustion21

LESSON11MethodsofDustControl23

PartⅢOtherTopics25

LESSON12MineDrainage25

LESSON13MineRescueOperations28

LESSON14SurvivalProgram30

LESSON15OriginofCoal32

LESSON16HistoryofCoalMining33

LESSON17AccidentPreventionPrinciples34

PartⅠMineVentilation

LESSON1IntroductiontoMineVentilation

Introduction

Mineventilationinvolvesthecontroloftheatmosphericenvironment.Thisrequirescontroloftheairqualityandairmovementtosatisfytherequirementsforthehealth,safetyandcomfortofmineworkers.Minimumstandardsaresetoutinthevariousstatesminesregulation.Somearedescriptive,specifyingthestandardsrequired（eg.Victoria）,andsomeareprescriptive,detailingexactlyhowthestandardsaretobeachieved（eg.W.A.）.

PurposesofMineVentilation

Properlyengineeredcontrolofthemineatmosphereisrequiredto:

·providefreshair（oxygen）formentobreathe

·provideasourceofoxygenforinternalcombustionenginesinmachinery

·diluteatmosphericcontaminantstoacceptablelevels

·maintaintemperatureandhumiditywithinacceptablelimits

·removeatmosphericcontaminantsfromthemine.

HistoricalDevelopment

Mineventilationistwofoldinpurpose:

first,itmaintainslife,andsecondlyitcarriesoffdangerousgases.Thehistoricroleofventilationwastoprovideaflowoffreshairsufficienttoreplacetheoxygenconsumedbytheminersworkingunderground.

Today'smineventilationprimarilydealswithnoxiousgases（mainlygeneratedbytracklessequipmentunderground）.

Inthepast,miningoccurrednear thesurfacewherenaturallightandventilation wasavailable.Fireswereusedtodrawfreshairintothemineandexhaustshaftsventedthehotsmokeoutofthemine.

LongbeforecoalwasminedinNorthAmerica,collieriesinEuropeweresunkwithdualentrances;onethroughwhichairflowedintothemineandanotherthroughwhichairflowedout.Initially,mineventilationwasassistedbyundergroundfurnaces,whichusedthepracticalprinciplethattheupdraftofafirecausedasuctionwhichdrewairoutofthemineandthisairwasreplacedbyairwhichwaspulledintofilltheopening.

Canariesaresaidtohavebeenusedtodetectgasincoalminesintheearlystagesofcoalmining.Thissensitivebirdwouldbetakenintotheworkingsand,ifitperished,thecollierswouldimmediatelyleavethemine.

However,beforethe1870s,managersandqualifiedpersonswereusingsafetylampstodetectgas.Thesesafetylampssoonreplacedoillampsandopenflaredcandlesasasourceofworkinglight.

Soon,smallhand-turnedfanswereusedtoblowoutgasfromworkingplacesintomainaircurrents.Trapdoorswerestrategicallyplacedaspartoftheventilationsystemtoguidetheflowofairtoorfromselectedareas."Trapper"boyswerepostedatthebusierdoorstoopenthemforthepassageofcoal,materialsandmen."Aircourses"werefrequentlycutthroughcoalandrock.

Inthe1920sthehand-turnedfanswerereplacedwithair-poweredsmallturbinefans.Largefansofthesuctiontypewereplacedonthesurfaceandgraduallyincreasedinsize.Airfromsurfacecompressorswaspipedintotheminetopowermachineryandtoassistinventilation.

PropertiesofAir

Theconstituentsofairare:

Constituent

Volume

Mass%

Nitrogen（N2）

78.09

75.53

Oxygen（O2）

20.95

23.14

CarbonDioxide（CO2）

0.03

0.04

RareGases（Ar,H2,He,etc.）

0.93

1.28

AtmosphericPressureatanypointisduetotheweightofairaboveit,andvarieswithaltitude（whichdeterminestheheightoftheaircolumn）,andairdensity（whichisdeterminedbytemperatureandmoisturecontent）.Standardatmosphericpressureistakenas760mmofHg,（101.3kPa）atmeansealevel,anditvariesbyaboutlkPaforevery90mincreaseordecreaseinaltitude.

AtmospherictemperatureisnormallygivenaccordingtotheCelsiusscale（°C）,buttheKelvinscale（°K）maybeused.

0°K

=

-273°C

（absolutezero）

273°K

=

0°C

（freezingpointofwater）

373°K

=

100°C

（boilingpointofwater）

Airisacolorless,odorless,tastelessgasmixturewhichsupportscombustionandlife.Inmineventilationweareusuallydealingwithanair/watervapormixturewhichhasdifferentthermodynamicpropertiestodryair.Thedensityofdryairis1.21kg/m³atstandardatmosphericpressure（101.3kPa）andtemperature（15°C）.

NewWordsandExpressions

mineventilation矿山通风

internalcombustionengine内燃机

dilute冲淡,变淡,变弱,稀释

contaminant污染物

noxious有害的

exhaustshaft出风井

colliery煤矿

sink挖掘

suction吸入,吸力,抽气,抽气机,抽水泵,吸引

canary[动]金丝雀,淡黄色

trapdoor通风门

trapper设阱捕兽者,[矿]矿井风门开关管理员

moisturecontent湿度

thermodynamic热力学的,使用热动力的

LESSON2EnergyChangesinFluidFlow

MineVentilationisnormallyanexampleofasteadyflowprocess,thatis,oneinwhichnoneofthevariablesofflowchangeswithtime.Transitionandlossinenergyareinvolvedinsuchaprocess,anditisimportanttounderstandtheirnatureandtobeabletoexpressthemmathematically.Energychangesarebasictothecalculationoftheminequantityandhead,oneoftheultimateobjectivesofmine-ventilationengineering.Anexpressionrelatingtheenergyvariablesmaybedevelopedasfollows.

Thetotalenergyatanysectioninamovingfluidconsistsofthesumoftheinternalstatic,velocity,potential,andheatenergiesatthatsection.Assumearealfluidmovinginaconduit,andconsidertheenergychangesthatoccurbetweenanytwosectionsinthesystem.Theheatchangesisgenerallynegligiblecomparedtotheotherterms,exceptindeepminesoronesnaturallyventilated,andtheadditionofmechanicalenergyisusuallyconsideredseparately.Omittingthesetermsfornow,thetotalenergyatsection1equalsthetotalenergyatsection2,plustheflowenergylossesoccurringbetween1and2：

（totalenergy）1=（totalenergy）2+（flowenergylosses）1-2

（1）

Orsubstitutingexpressionsforthevariousenergytermsanddisregardingtheminorchangeininternalenergy,thefollowinggeneralenergyequationforfluidflowresults:

（2）

Where:

--------staticenergy;

-------velocityenergy;

Z1,Z2----------potentialenergy;

H1-2----------flowenergyloss.

Equation2isrecognizedasthefamiliarBernoulliequation,applicabletoallfluid-flowprocesses.Inthisform,itappliedonlytoanincompressiblefluid,whichairisassumedtobeinnearlyallmineventilationbecauseofminorchangesinairdensity.

Eachtermintheequationisactuallyaspecificenergy,inunitofm.kg/kg,orm.Sincemisameasureoffluid,headthesetermscanalsobereferredtoaspressureheadsorsimplyheads.Indealingwithair,itiscustomarytoemploymmofwaterrathermofanairastheunitofhead.

Acceptingtheequivalencyofspecificenergyandhead,thegeneralequationaswritteninEq.1canalsobeexpressed:

（3）

Where:

Httotalhead;andEq.2canbeexpressed:

Hs1+Hv1+Hz1=Hs2+Hv2+Hz2+H1-2（4）

WhereHsisstatichead,Hvisvelocityhead,andHziselevationorpotentialhead,allheadshavetheunitofmmwater.

TheseversionsoftheBernoullienergyequation（Eq.2and4）arebothbasicandgeneralandthemostusefultoemployinmineventilation.Inrelationthestaticvelocity,potential,andtotalheadsplusthelossesflow,theenergyequationpermitswritingofanexpressionencompassingallflowvariablesbetweenanytwopointsintheventilationsystem.Thesepointsmaybeselectedatthebeginningandendofthesystem（theentranceanddischargeofminefortheaircircuit）,enablingthecalculationofthecharacteristicsfortheentiresystem（themineheads）.

NewWordsandExpressions

head液压，气压：

液体或气体产生的压力；压差

staticenergy静压能

velocityenergy动能

potentialenergy位能、势能

incompressiblefluid不可压缩流体

LESSON3FaceVentilation

Unlesstheairisproperlydistributedtotheface,themineventilationsystemisnotperformingitsprimaryfunction.Whileithasalwaysbeenrecognizedthatthislastpartofventilationisthemostimport,itisalsothemostdifficulttoachieve.

Therearebasicallytwomethodsofventilatingtheblindentriesaheadofthelastopencrosscut:

theuseoflinebratticesortheinstallationofauxiliaryfans.Eachtechniquehasitsdefendersaswellasitsoutspokencritics.

LineBrattices

Thelinebratticeisessentiallyaspacedividerortemporarypartitionmadeofanimperviousmaterialthatisinstalledandmaintainedverycarefullyandkeptasclosetothefaceaspossible.Itspurposeistoguidetheairflowthroughthefaceareaandlastopencrosscutandintothereturn.Bratticeswereformerly（andtosomeextentstillare）madeofuntreatedjute,butnylonreinforcedplasticsandsimilarmaterialsaremorecommonlyusedinthemtoday.Whilethemoreeffectivematerialisinvariablyhigherininitialcost,itresultsinloweroverallexpenseinthatitallowsforgreaterreuseandlessairleakage.

Thelinebratticeisinstalledsoastosplittheheadinglongitudinallyandthusprovidesaninletaswellasareturnfromthefacetothelastopencrosscut.Sincetheminingmachinemusthaveroomtomaneuverononesideofthebrattice,itisnotpracticaltosplittheentryevenly,soawidesideisprovidedforthemachine.Theairmaybebroug