正做專業(yè)英語(L11)

PartⅡMineSafety

LESSON11MethodsofDustControl[教學內(nèi)容]

IntroductionVentilationWaterspraysDustcollectors

LESSON11MethodsofDustControl[教學目的]

要求學生熟記專業(yè)詞匯，達到英文與中文相互熟練翻譯的程度aerosol['ε?r?s?l]Microflora[,maikr?u'fl?:r?]

respiratory['resp?r?t?ri]abrasion[?'brei??n]

boringextractionlongwallsheareraerosol浮質(氣體中的懸浮微粒,如煙,霧等)microflora微植物群respiratory呼吸的abrasion磨損boring打眼；鉆進；鉆探extraction開采longwall長壁開采法shearer（滾筒式）采煤機

[教學目的]

深入理解Ventilation、Watersprays等內(nèi)容，達到熟練閱讀和正確、通順地翻譯的程度；了解Dustcollectors等內(nèi)容，達到比較熟練和比較通順翻譯的程度。LESSON11MethodsofDustControl[教學重點、難點]

Ventilation[課時安排]

1.5credithour[授課方法]

講授與討論相結合LESSON11MethodsofDustControl復習舊課1．回憶SHT、chemisorption（化學吸附作用）專業(yè)詞匯的中文含義；氧化作用（oxidation）、采空區(qū)（goaforgob）、自燃傾向性susceptibilitytospontaneouscombustion英文表達。2．Pleasedescribetheprimarydangersofconcealedfires.(theevolutionofcarbonmonoxide,theignitionofmethaneandcombustionprogressingintoairwaystoproduceopenfires)LESSON11MethodsofDustControl

Thenaturalatmospherethatwebreathecontainsnotonlyitsgaseousconstituentsbutalsolargenumbersofliquidandsolidparticles.Theseareknownbythegeneric[d?i'nerik]name

aerosols['ε?r?s?l].Theyarisefromacombinationofnaturalandindustrialsourcesincludingcondensation([,k?nden'sei??n]壓縮；凝結；冷凝)

,smokes,volcanicactivity,soilsandsands,andmicroflora.LESSON11MethodsofDustControlgenericname通用名類屬名aerosol浮質(氣體中的懸浮微粒,如煙,霧)

microflora微植物群

Thenaturalatmospherethatwebreathecontainsnotonlyitsgaseousconstituentsbutalsolargenumbersofliquidandsolidparticles.Theseareknownbythegenericnameaerosols.我們呼吸的自然大氣中，不僅包含氣態(tài)成分，而且還包含大量的液體和固體微粒。它們統(tǒng)一名稱為懸浮微粒。Theyarisefromacombinationofnaturalandindustrialsourcesincludingcondensation,smokes,volcanicactivity,soilsandsands,andmicroflora.懸浮微粒的產(chǎn)生有自然方面又有工業(yè)方面的原因，這包括：凝結、煙氣、火山活動、沙土和微植物群。Mostoftheparticlesaresmallenoughtobeinvisibletothenakedeye.Dustisthetermweuseinreferencetothesolidparticles.Thephysiologiesofair-breathingcreatureshaveevolvedtobeabletodealefficientlywithmostoftheaerosolsthatoccurnaturally.LESSON11MethodsofDustControlphysiology[,fizi'?l?d?i]

生理學Mostoftheparticlesaresmallenoughtobeinvisibletothenakedeye.Dustisthetermweuseinreferencetothesolidparticles.大部分微粒足夠小，以至于肉眼看不到。我們使用粉塵這個術語特指這種固體顆粒。Thephysiologies([,fizi'?l?d?i]生理學,生理機能)ofair-breathingcreatureshaveevolvedtobeabletodealefficientlywithmostoftheaerosolsthatoccurnaturally.呼吸空氣的生物的生理機能已進化為能夠有效地對付自然情況下產(chǎn)生的懸浮顆粒。However,withinclosedindustrialenvironments,concentrationsofairborneparticulatesmayreachlevelsthatexceedtheabilityofthehumanrespiratorysystemtoexpeltheminatimely['taimli]

manner.Inparticular,mineraldustsareformedwheneverrockisbrokenbyimpact,abrasion,crushing,cutting,grindingorexplosives.LESSON11MethodsofDustControlHowever,withinclosedindustrialenvironments,concentrationsofairborneparticulatesmayreachlevelsthatexceedtheabilityofthehumanrespiratorysystemtoexpeltheminatimelymanner.然而，在封閉的工業(yè)環(huán)境內(nèi)，懸浮空氣中的微粒濃度可能超過人類呼吸系統(tǒng)能及時排除它們的程度。Inparticular,mineraldustsareformedwheneverrockisbrokenbyimpact,abrasion[?'brei??n],crushing,cutting,grinding['ɡraindi?]orexplosives尤其是，只要巖石受撞擊、磨損、破碎、切割、研磨或者爆破碎裂時，就能形成礦塵。Thefragmentsthatareformedareusuallyirregularinshape.Thelargetotalsurfaceareaofdustparticlesmayrender(['rend?]致使)themmoreactivephysically,chemicallyandbiologicallythantheparentmaterial.Thishasanimportantbearingontheabilityofcertainduststoproducelung[l??]diseases.LESSON11MethodsofDustControlhaveabearingon[upon]關系到...,影響到...renderassistance.給予(提供)援助Thefragmentsthatareformedareusuallyirregularinshape.形成的碎片通常在形狀上是不規(guī)則的。Thelargetotalsurfaceareaofdustparticlesmayrenderthemmoreactivephysically,chemicallyandbiologicallythantheparentmaterial.物質破碎后形成的塵?？偙砻娣e增大，從而在物理、化學和生物方面活性增強。Thishasanimportantbearingontheabilityofcertainduststoproducelungdiseases.這使某些粉塵能夠引起肺病。Thethreemajorcontrolmethodsusedtoreduceairbornedustintunnelsandundergroundmines:ventilation,water,anddustcollectors.LESSON11MethodsofDustControldustcollector吸塵器drycentrifugal[sen'trifjuɡ?l]collector

干式離心除塵器Thethreemajorcontrolmethodsusedtoreduceairbornedustintunnelsandundergroundmines:ventilation,water,anddustcollectors.減少隧道內(nèi)和地下礦山中的懸浮粉塵，有三種主要控制方法：通風、水和集塵器。VentilationVentilationairreducesdustthroughbothdilutionanddisplacement.Thedilutionmechanismoperateswhenworkersaresurroundedbyadustcloudandadditionalairservestoreducethedustconcentrationbydilutingthecloud.LESSON11MethodsofDustControlVentilationairreducesdustthroughbothdilutionanddisplacement.通風氣流通過稀釋和置換減少粉塵Thedilutionmechanismoperateswhenworkersaresurroundedbyadustcloudandadditionalairservestoreducethedustconcentrationbydiluting[～e：dai'lju:t]thecloud.當工人處于粉塵云的包圍中，稀釋過程起作用，附加的氣流通過稀釋塵云，減少粉塵的濃度。Thedisplacementmechanismoperateswhenworkersareupwindofdustsourcesandtheairvelocityishighenoughtoreliablykeepthedustdownwind.LESSON11MethodsofDustControlThedisplacementmechanismoperateswhenworkersareupwindofdustsourcesandtheairvelocityishighenoughtoreliablykeepthedustdownwind.當工人位于塵源的上風方向，而且氣流速度足夠高，使之能夠可靠地保持粉塵處在下風方向時，置換過程起作用。DilutionVentilation.Thebasicprinciplebehinddilutionventilationistoprovidemoreairanddilutethedust.Mostofthetimethedustisreducedroughlyinproportiontotheincreaseinairflow,butnotalways.Thecostofandtechnicalbarriers

toincreasedairflowcanbesubstantial,particularlywhereairalreadymovesthroughventilationductworkorshaftsatvelocitiesof3,000ft/minormore.

Substantial(相當)大的ductworkn.管道系統(tǒng)LESSON11MethodsofDustControl1)DilutionVentilation.Thebasicprinciplebehinddilutionventilationistoprovidemoreairanddilutethedust.1）稀釋通風稀釋通風的基本原理是提供更多的空氣來稀釋粉塵。Mostofthetimethedustisreducedroughlyinproportiontotheincreaseinairflow,butnotalways.大多數(shù)情況下，減少的粉塵與增加的風量大致成比例，但并不總是這樣。Thecostofandtechnicalbarrierstoincreasedairflowcanbesubstantial,particularlywhereairalreadymovesthroughventilationductworkorshaftsatvelocitiesof3,000ft/minormore.增加風量的費用和技術障礙可能是關鍵，尤其是在流過通風管道或井筒的氣流速度已達到3000英尺/分（914.4m/min）以上的礦井，更是如此。2)DisplacementVentilation.Thebasicprinciplebehinddisplacementventilationistousetheairflowinawaythatconfines[k?n'fain]thedustsourceandkeepsitawayfromworkersbyputtingdustdownwindoftheworkers.LESSON11MethodsofDustControl2)DisplacementVentilation.2）置換通風Thebasicprinciplebehinddisplacementventilationistousetheairflowinawaythatconfinesthedustsourceandkeepsitawayfromworkersbyputtingdustdownwindoftheworkers.置換通風的基本原理是利用風流約束塵源，使粉塵處在下風位置，從而遠離工人。Everytunnelorminepassagewithanairflowdirectionthatputsdustdownwindofworkersusesdisplacementventilation.Inmines,continuousminerfacesortunnelboringmachinesonexhaustventilationusedisplacementventilation.LESSON11MethodsofDustControlcontinuousminerfaces:連續(xù)采煤機工作面tunnelboringmachines:隧道掘進機Everytunnelorminepassagewithanairflowdirectionthatputsdustdownwindofworkersusesdisplacementventilation.任一隧道或礦山通道中，如風流方向使粉塵處在下風方向，使用的就是置換通風。Inmines,continuousminerfacesortunnelboringmachinesonexhaustventilationusedisplacementventilation.在礦山中，連續(xù)采煤機工作面或隧道掘進機的回風系統(tǒng)，使用的是置換通風Enclosureofadustsource,suchasaconveyorbelttransferpoint,alongwithextractionofdustyairfromtheenclosure,isanotherexampleofdisplacementventilation.Displacementventilationcanbehardtoimplement.LESSON11MethodsofDustControlimplementvt貫徹執(zhí)行Enclosureofadustsource,suchasaconveyorbelttransferpoint,alongwithextractionofdustyairfromtheenclosure,isanotherexampleofdisplacementventilation.在塵源附近，例如運輸皮帶轉載點，將塵源連同周圍多塵空氣一起抽出去，是置換通風的另一個例子。Displacementventilationcanbehardtoimplement.置換通風很難實現(xiàn)However,ifdonewell,itisthemosteffectivedustcontroltechniqueavailable,anditisworthconsiderableefforttogetitright.Thedifficultyisthatwhenworkersarenearadustsource,say,10to20ftfromthesource,keepingthemupwindrequiresasubstantialairvelocity,typicallybetween60and150ft/min.Thereisnotalwaysenoughairavailabletoachievethesevelocities.LESSON11MethodsofDustControlHowever,ifdonewell,itisthemosteffectivedustcontroltechniqueavailable,anditisworthconsiderableefforttogetitright.然而，如果做得好，置換通風是能利用的最有效的粉塵控制技術，值得付出大量的努力，使其運行良好。Thedifficultyisthatwhenworkersarenearadustsource,say,10to20ftfromthesource,keepingthemupwindrequiresasubstantialairvelocity,typicallybetween60and150ft/min.困難之處在于：當工人處在塵源附近時，比方說10~20英尺，使他們位于上風處需要相當大的風速（一般要60～150英尺/分）。Thereisnotalwaysenoughairavailabletoachievethesevelocities.并不總有足夠的風量能達到這么大的風速。WaterspraysTheroleofwaterspraysinminingisadual['dju:?l]one:(1)wettingofthebrokenmaterialbeingtransportedand(2)airbornecapture.Ofthetwo,wettingofthebrokenmaterialisfarmoreeffective.LESSON11MethodsofDustControlTheroleofwaterspraysinminingisadualone:(1)wettingofthebrokenmaterialbeingtransportedand(2)airbornecapture.Ofthetwo,wettingofthebrokenmaterialisfarmoreeffective.開采中噴水的作用是雙重的：（1）濕潤正被運輸?shù)姆鬯榈奈镔|；（2）空中捕獲。這兩個作用中，濕潤粉碎物質更加有效。Adequatewettingisextremelyimportantfordustcontrol.Thevastmajorityofdustparticlescreatedduringbreakagearenotreleasedintotheair,butstayattachedtothesurfaceofthebrokenmaterial.Wettingthisbrokenmaterialensuresthatthedustparticlesstayattached.LESSON11MethodsofDustControlAdequatewettingisextremelyimportantfordustcontrol.Thevastmajorityofdustparticlescreatedduringbreakagearenotreleasedintotheair,butstayattachedtothesurfaceofthebrokenmaterial.適度的濕潤對于粉塵控制非常重要。在粉碎過程中產(chǎn)生的粉塵顆粒大部分沒有釋放到空氣中，而是附著在粉碎物的表面。Wettingthisbrokenmaterialensuresthatthedustparticlesstayattached.濕潤破碎物能夠確保粉塵顆粒保持附著狀態(tài)。Asaresult,addingmorewatercanusually(butnotalways)becountedontoreducedust.Forexample,coalmineoperatorshavebeenabletoreducethedustfromhigherlongwallproductionlevelsbyraisingtheshearerwaterflowratetoanaverageof100gpm.LESSON11MethodsofDustControlAsaresult,addingmorewatercanusually(butnotalways)becountedontoreducedust.因此，通常加水越多越能降低粉塵（但并不總是如此）。Forexample,coalmineoperatorshavebeenabletoreducethedustfromhigherlongwallproductionlevelsbyraisingtheshearerwaterflowratetoanaverageof100gpm例如，煤礦經(jīng)營員已能夠通過提高（滾筒式）采煤機的水流速度平均達到100gpm(每分鐘100加侖)，來減少生產(chǎn)水平較高的長壁開采工作面的粉塵。Comparedtotheamountofcoalmined,onaweightbasis,this100gpmisequivalentto1.9%addedmoisturefromthesheareralone.Unfortunately,excessivemoisturelevelscanalsoresultinahostofmaterialshandlingproblems,operationalheadaches,andproductqualityissues,soanupperlimitonwateruseissometimesreached

ratherquickly.LESSON11MethodsofDustControlComparedtotheamountofcoalmined,onaweightbasis,this100gpmisequivalentto1.9%addedmoisturefromthesheareralone.與開采煤的數(shù)量相比，以重量為基礎，由采煤機每分鐘單獨加入的100加侖水分等于開采煤量的1.9%。Unfortunately,excessivemoisturelevelscanalsoresultinahostofmaterialshandlingproblems,operationalheadaches,andproductqualityissues,soanupperlimitonwateruseissometimesreachedratherquickly.可惜的是，過高的水分也能導致許多材料的處理問題、操作上的不便和產(chǎn)品質量問題，所以，用水的上限有時能很快達到。Asaresult,analternativetosimplyaddingmorewateristoensurethatthebrokenmaterialisbeingwetteduniformly.LESSON11MethodsofDustControlAsaresult,analternativetosimplyaddingmorewateristoensurethatthebrokenmaterialisbeingwetteduniformly.因而，確保粉碎的物質能夠得到均勻加濕是替代僅靠增加水量降塵的另一種方法。Underactualminingconditions,thetypicalwatersprayoperatingat100psiand1-2gpmgivesnomorethan30%airbornecaptureofrespirabledust.Thisisnotasgoodaslabtestswouldleadonetobelieve.Inlabtests,sprayswereusuallyconfinedinaduct,andallofthedustwasforcedtopassthroughthespray.LESSON11MethodsofDustControlpsi:PoundsperSquareInch.磅/平方英尺gpm:GallonsPerMinuteUnderactualminingconditions,thetypicalwatersprayoperatingat100psi（poundspersquareinch）and1-2gpmgivesnomorethan30%airbornecaptureofrespirabledust.Thisisnotasgoodaslabtestswouldleadonetobelieve.Inlabtests,sprayswereusuallyconfinedinaduct,andallofthedustwasforcedtopassthroughthespray.這并不與實驗室試驗的結果完全一樣。在實際開采條件下，以100psi和1-2gpm實施典型的水噴霧，最多能捕獲30%的風載可吸入粉塵。在實驗室的試驗中，水噴霧通常限定在管道中，所有的粉塵被迫穿過水噴霧。However,underactualminingconditions,dustcloudsareunconfined.Inallsprays,themovingdropletsexert[iɡ'z?:t]drag[dr?ɡ]ontheadjacent([?'d?eis?nt]鄰近的)air;thus,spraysacttomovetheair.Becauseofthisairentrainmenteffect,ifasprayisaimedatanunconfineddustcloud,itwillcarryinairthatspreadsthecloud,thusmakingcapturebythespraylessefficient.

LESSON11MethodsofDustControlEntrainmentn.帶走,夾帶However,underactualminingconditions,dustcloudsareunconfined.Inallsprays,themovingdropletsexertdragontheadjacentair;thus,spraysacttomovetheair.Becauseofthisairentrainmenteffect,ifasprayisaimedatanunconfineddustcloud,itwillcarry(被攜帶)

inairthatspreadsthecloud,thusmakingcapturebythespraylessefficient.Attemptstoimprovetheairbornecaptureefficiencyofsprayshavenotmetwithpracticalsuccess.Oneapproachhasbeentoreducedropletsize,basedonthenotionthatcapturebysmallerdropletsismoreefficient.LESSON11MethodsofDustControlNotion['n?u??n]

n.概念,觀念,想法,意見,打算,Attemptstoimprovetheairbornecaptureefficiencyofsprayshavenotmetwithpracticalsuccess.Oneapproachhasbeentoreducedropletsize,basedonthenotionthatcapturebysmallerdropletsismoreefficient.DustcollectorsDustcollectorscanplayavaluableroleindustreduction—ifspaceisavailabletolocatethecollectorandifthecollectorefficiencyishigh.Dustcollectorsrangefromlow-volumefiltration[fil'trei??n]systemsusedinthecabs

[k?b]ofminingequipmenttohigh-volumewetcollectorsusedoncontinuousminersincoalmines.LESSON11MethodsofDustControlDustcollectorscanplayavaluableroleindustreduction—ifspaceisavailabletolocatethecollectorandifthecollectorefficiencyishigh.Dustcollectorsrangefromlow-volumefiltrationsystemsusedinthecabsofminingequipmenttohigh-volumewetcollectorsusedoncontinuousminersincoalmines.Itisimportanttorecognizethattheefficiencyofadustcollectoristhefiltrationefficiencyoftheunittimesthecaptureefficiencyofitsinlet['inlet].Forcollectorsproperlydesignedtotraprespirabledust,thefiltrationefficiencyisusuallyquitehigh,inthe90%-95%range.LESSON11MethodsofDustControlItisimportanttorecognizethattheefficiencyofadustcollectoristhefiltrationefficiencyoftheunittimesthecaptureefficiencyofitsinlet.Forcollectorsproperlydesignedtotraprespirabledust,thefiltration