钢铁冶金专业英语课件.ppt

SpecialtyEnglishforIron SteelMetallurgy Xu lingChen 陈许玲 E mail csuchenxuling MobiletelephoneQnumber 413645166 TeachingPurpose 掌握钢铁冶金工程的基本专业英语词汇 能够阅读钢铁冶金及相关行业的英文文献 及时掌握国外相关领域的发展动态和新技术 提高翻译技巧和分析难句的能力 正确 通顺 快速地把冶金专业的英文资料译成中文 初步掌握把汉语专业文章译成英文的能力和英语听说能力 TeachingContent TheoriesandTechnicsofAgglomerationTheoriesandTechnicsofIronmakingTheoriesandTechnicsofSteelmakingIntroductionofIronandSteelIndustryinWorld Section Agglomeration 1 1TrendsinAgglomeration1 1 1Thegrowthofsinteringandpelletizing1 1 2Locationofsinteringandpelletizingplants1 1 3Futuredevelopments1 2 ModernAgglomerationPractice1 2 1Sintering1 2 2Pelletizing 造块SinteringPelletizingBriquetting Section Agglomeration 1 1 1Thegrowthofsinteringandpelletizing Sinterproductiongrewslowlyfromitsinception in1911 tothecommencementoftheSecondWorldWar reachingsixmilliontonsinboththeU S A andtheU S S R by1940 Pelletizingcommencedmuchlater intheearly1950sintheU S A andnotuntilthemiddle1960sintheU S S R Thegrowthofsinterandpelletproductioninthesetwocountries andofsinterproductionintheU K isshowninFigure1 1 Section Agglomeration 1 1 1Thegrowthofsinteringandpelletizing Thefollowingaimshaveresultedinthegrowthofsinteringandpelletizingintheseandothercountries l Toimprovethesizegradingandthereducibilityofthefurnaceburdenwithoutwastingtheorefines 2 Toutilizecertainwasteproductscontainingiron e g blast furnacefluedust 3 Tominimizethequantityofvolatilematterchargedtothefurnace 4 Toutilizefineconcentratesproducedfromlow gradeores 5 Toenableorefinesandconcentratestobeprocessedatorneartheminesiteandthustoenhancethevalueofexportedore 粒度组成size graindistribution sizecomposition dimensionratio cause leadto bringabout Section Agglomeration 1 1 1Thegrowthofsinteringandpelletizing Bothsinteringandpelletizingenableitem1tobeaccomplished Pelletizingissuperiorinthatthefinalproductsizeismorecloselycontrolledbutthereisnoevidencetosuggestthattheclosesize gradingofpelletsenableseithertheoutputorthethermalefficiencyofablastfurnacetobebetterthanthatwhichcanbeobtainedusingsinter Sinterplantsarebettersuitedthanpelletplantsforutilizingwastematerials andincertainAmericanworkswhichusehighproportionsofpellets thesinterplanthasbeenreducedalmosttotheroleofprocessorofwastematerialsandcalcinerofflux However apelletizingplanthasbeenbuiltinItalysolelytoprocesspyritesresidues aby productfromthesulphurindustry andinCanadapelletsareproducedfromtheby productsofthenon ferrousindustry 煅烧 熔剂硫铁矿烧渣硫 有色 Section Agglomeration 1 1 1Thegrowthofsinteringandpelletizing Volatilesarecontainedinthefluxandalso toalesserextent incertainores Theadditionoflimestonetothesintermixtoproduceafluxedsinter basicityl 0 1 4 hasbeenpractisedformanyyears andmorerecentlysuper fluxedinterswithbasicitiesashighas3 0 4 0havebeenmade Theuseofsuchsintersenablesamixtureofores orpellets andsintertobeusedasblast furnaceburdenwithonlyaminimumofraw uncalcined flux Ithasalsobeencommonpracticeforsomeyearstosinterlow gradeoresofhighvolatilecontent ThishasgreatlyimprovedfurnaceoperationinthoseregionsoftheUnitedKingdomandWesternEuropewheresuchoresarethebasisofironmaking calciumcarbonateburntlime生石灰 dolomite白云石 olivine橄榄石 serpentine蛇纹石 magnesite菱镁石 Section Agglomeration 1 1 1Thegrowthofsinteringandpelletizing TwopelletplantsinNorthAmericahavebeenbuilttoprocesslimoniteoreatthemineandsoshiparicherproduct inamoredesirablephysicalstate tothesteelworks Fluxedpelletshavebeenmadeandchargedtotheblastfurnace butonlyinrelativelysmallquantities anditistooearlytoassesstheirbehaviourintheblastfurnace Itisunlikely however thatitwouldbeeconomicallyjustifiabletotransportfluxtothepelletizingplantandthenshipit aspartofthefluxedpellet foraconsiderabledistancetothesteelworks Limonite褐铁矿Hematite赤铁矿 Magnetite磁铁矿 Siderite菱铁矿 Goethite针铁矿 Section Agglomeration 1 1 1Thegrowthofsinteringandpelletizing Pelletizingwasdevelopedinitiallyasamethodofprocessingfineconcentrates Extensivetestswerecarried outintheU S A around1950todevelopwaysofagglomeratingthefineconcentratesobtainedfromtaconites 铁燧石 Bothsinteringandnodulizingweretriedandabandonedaslesssuitablethanpelletizing Thewidespreaddevelopmentoflow gradeorebodiesintheU S A Canadaandelsewhere inthe1950sand1960s providedthestimulusforthegrowthofpelletizingcapacitywhichisshowninFigure1 2 Morerecentlyanumberofpelletplantshavebeenbuilttoproducepelletsfromhigh gradeorefines Thisenhancesthevalueoftheproduct 1 1 2Locationofsinteringandpelletizingplants Sinteringisalwayslikelytobecarriedoutatthesteelworks Sinterdoesnotwithstandhandingverywell andthelessthehandlingbetweenthesinterplantandtheblastfurnace thebetter Addedtothisisthefactthatcertainoftherawmaterials e g fluedustandcokebreeze arisewithintheworks Ontheotherhand pelletizingislikelytobecarriedoutatorneartheminesite Therearesomeexceptionstothis atChiba theKawasaki 川崎 SteelCompanycommencedmakingpelletsin1953 Thefineoreusedintheworkswasdividedintotwostreams thatmostsuitedtopelletizing e g fineconcentrates andthatmostsuitedtosintering e g theundersizefromorescreening Itwasclaimedthatinthiswaysinteringpracticewasimprovedandthepre treatmentofthepelletizingmixwasminimized PelletplantshavebeenbuiltattwootherJapaneseworksandanotherhasbeenbuiltinHolland However thevastmajorityofnewplantsarebeingbuiltatornearthemines Pelletizingworksmosteffectivelyiftherawmaterialfeedisconsistent andthiscanmoreeasilybeensuredifthepelletplantandtheminearecloselylinked Thereisalsoanunderstandabledesireonthepartoftheexportingcountrytoprovideamorevaluablematerial Thedataonpage12givesanexampleofthedifferenceinvaluebetweenpelletsandtheorefinesfromwhichtheywereproduced Figure1 2Worldpelletcapacity Itisdangeroustopredictfuturedevelopmentsfromwhathashappenedinthepast However certaintrendsarefairlyclear Sinteringwillcontinuetobeimportant Theincreasingemphasisonacloselysizedburdenrendersitinevitablethatoreandpelletscreeningswillcontinuetobeproducedatthesteelworks Itismostimprobablethatallthefinesarisingatthemineswillbepelletizedbeforedispatch Itismuchmorelikelythatabalancewillalwaysbemaintainedbetweenfinessoldrelativelycheaplyandthemoreexpensivepellets Addtothisthenecessityforutilizingwastematerialsarisinginthesteelworks e g fluedust andthedesiretocalcinethefluxbeforechargingittothefurnace andthefutureofsinteringappearstobeassured Theonlydevelopmentswhichcouldupsetthiswouldbethedevelopmentofanewagglomerationprocessoramodificationofthepelletizingprocesswhichenablesittoaccommodateacoarserfeed Theonlynewprocesswhichhasappearedoverthehorizoninrecentyearsishotbriquetting andthishasnotfulfilleditsearlierhopes Recentworkhasestablishedthatpelletscanbemadefromcertainoremixeswithouthavingalltheinputfinelyground butsomegrindingisstillnecessaryandnotalloremixesaresuitableforthistypeofpelletizingoperation Thisworkhasnotbeencarriedoutonalargescaleandthebehaviourofsuchpelletsintheblastfurnacehasnotbeeninvestigated 1 1 3 1Statusofsinteringandpelletizing Section Agglomeration Pelletizingalsoappearstohaveanassuredfuture Takingalong termview anincreasingproportionoftheblast furnaceburdenislikelytocomefromlow gradedeposits Thesecanbepelletizedmostconvenientlyatornearthemineandshippedintheprocessedform Itisalsoprobablethatthepresenttrendofpelletizingpartoftheore richfinesbeforesellingwillcontinue Itisnotpossibletopredicthowtheoverallbalancebetweensinteringandpelletizingwillchangewithtime Inanycaseitislikelytovarygreatlyfromcountrytocountry andbothprocessescouldeventuallyberenderedunnecessarybyradicalnewdevelopmentsinironmaking 1 1 3 1Statusofsinteringandpelletizing Section Agglomeration 1 1 3 2Metallizedagglomerates Theaiminrecentyearshasbeentominimizethemetallurgicalloadontheblastfurnace Thishasresultedinlimitingthechemicaloperationstobeperformedtothereductionofironoxides togetherwithsmallquantitiesofotheroxides andslagformation Thevolumeofslaghasbeenreducedtothenecessaryminimumsothattheheatneededformeltinghasbeenminimized Themainthermalloadistheenergyrequiredforreducingironoxide andtheworktobedoneintheblastfurnacewouldbereducedifpartoftheoxygenwasremovedbeforecharging Becauseoftheoperatingconditionswithintheblastfurnace reducingthehigheroxidestoferrousoxidedoesnotlowertheblast furnacefuelconsumption Toachievethisitisnecessarytoreduceatleastaproportionoftheirontothemetallicstate Section Agglomeration 1 1 3 2Metallizedagglomerates Itisnotpossibletomakehighlyreducedsinterbyincreasingthecokecontentofthemix Thehigherbedtemperaturesobtained andthereducingatmosphere leadtotheproductionofahighproportionofpartlyreducedferruginousslag Ontheotherhand highlyreduced metallized pelletscanbeproducedbymodificationsofthenormalhardeningprocedure Metallizedpelletscanbemadefromfiredoxidizedpellets butitisalsopossibletohardenthegreenpelletsunderreducingconditionstoproducethemetallizedpelletsinoneoperation Twomethodsarebeingusedcommercially ahorizontalrotarykilnandavertical shaftkiln Section Agglomeration 1 1 3 2Metallizedagglomerates TheSL RNprocessusesahorizontalrotarykiln Greenorfiredpelletsandasolidfuel finecoalorcoke andfinefluxarefedintotherotarydrum Thesolidstravelthroughthedrumcounter currenttothecombustiongasesfromagas oroil firedburnerlocatedintheexitfromthedrum Thereducedpelletsarecooledinaseconddrum andseparatedfromthespentfluxandexcesssolidfuel Figure1 3showsthelayoutofanSL RNplant CommercialplantshavebeenbuiltinNewZealand SouthKoreaandCanada Figure1 3 TheSL RNprocess Section Agglomeration Spongeiron Section Agglomeration 1 1 3 2Metallizedagglomerates Anumberofshaft furnaceprocesseshavebeendeveloped IntheWibergprocess firedoxidizedpelletsarereducedinashaftbygasesproducedinanelectricallyheatedgascarburizer IntheMidlandRossshaftprocess Midrexprocess firedoxidizedpelletsarereducedinashaftbygasesproducedbyreformingmethane 甲烷 ThesamemethodofproducingreducinggasesisusedinthePuroferprocess butheretheintentionistouseunfiredgreenpelletsandtoreduceandhardeninthesameoperation Commercialshaft furnaceplantsareinoperationorunderconstructioninSweden Japan theU S A andGermany Metallizedagglomeratescanalsobeproducedbyreducingfineironore forexampleinfluidizedbeds andbriquettingtheproduct AcommercialplantusingthismethodhasbeenbuiltinVenezuela Section Agglomeration 1 1 3 2Metallizedagglomerates Metallizedpelletshaveonlybeenusedasablastfurnaceburdenforshorttrialperiods Theresultswereencouraginginthatoutputsroseandcokeratesfell buttheeconomicadvantagesareverydoubtful Whilstmetallizedagglomeratesmaybeusedtoalimitedextentasablast furnacefeed itseemslikelythat inthemain theywillbemeltedandrefineddirectlytosteel thusby passingtheblastfurnacealtogether Inthiscase themanufactureofmetallizedpelletsbecomesanalternativeironmakingprocesslikethosedescribedinChapter3 Thisisborneoutpractically sincemostoftheprocessesformakingmetallizedpelletscanalsooperateusingsizedorewhich whenreduced ismeltedandrefinedtosteel Section Agglomeration 1 1 3 3Technicalbasesofsinterandpellet plantdesignandoperation Before1945littlewasknownofthebasicprinciplesunderlyingthesinteringprocess andthedesign constructionandoperationofsinterplantswaslargelybasedonexperience Inthenextfifteenyearsorsogreateffortsweremadetorectifythisposition Laboratorystudieswerecarriedoutaimedatelucidatingthebasictheory bothchemicalandphysical andpilot plantstudiesandinvestigationsoncommercialplantsweremadetoprovideabasisforplantdesignandoperation Duringthisperiod workwascarriedoutinmanycountriesinuniversities researchassociations steelworksandbyplantmanufacturers Interchangeofinformationwasgoodandtheresultswererapidlyincorporatedintothedesignandoperationofsinterplants Threeinternationalmeetingswereheldduringthisperiod inLondonin1953 inParisin1957 andinPhiladelphiain1961 whichprovidedusefulopportunitiesfortheexchangeofinformation Section Agglomeration 1 1 3 3Technicalbasesofsinterandpellet plantdesignandoperation Ataboutthesametime thebasicresearchanddevelopmentwhichledtotheestablishmentofthepelletizingindustrywasbeingcarriedout MuchofthebasicworkwascarriedoutintheUniversityofMinnesotaandlaterbyJernkontoretinSweden Assoonasithadbeenprovedthatpelletizingwasofpotentialcommercialimportance i e bytheearly1940s theAmerican andlatertheEuropean plantmanufacturerscarriedoutonthemechanismofballingandontheproblemsconnectedwithheatforthecommercialexploitationoftheidea Duringthisperiod basicstudieswerecarriedoutonthemechanismofballingandontheproblemsconnectedwithheatflowduringpelletfiring Section Agglomeration 1 1 3 3Technicalbasesofsinterandpellet plantdesignandoperation Atthepresenttime thedesignandoperationofbothsinterandpelletplantsarefirmlybasedonanunderstandingofbasicfactorswhichcontroltheprocesses Thebasictheoryisdiscussedintheearlychaptersofeachsection andtheapplicationofthistheorytoconstructionandoperationofcommercialplantsisconsideredinlaterchapters Section Agglomeration 1 2 ModernAgglomerationPractice1 2 1Sintering1 2 2Pelletizing Section Agglomeration Figure1 4showsthegeneralarrangementofasinterplant Theplantmayconvenientlybedividedintothefollowingsections 1 Proportioningofrawmaterials 2 Mixing 3 Loadingofmixontostrand 4 Ignition 5 Sintering 6 Sintertreatment 7 Wastegassystem 1 2 1 1Generalplantlayout Section Agglomeration 1 2 1 1Generalplantlayout Figure1 4Generalarrangementofasinterplant Section Agglomeration Therawmaterialsusedareasfollows 1 Ironorefines normally 1 2in 12mm Itisundesirabletohavelargerlumpsanditisalsoundesirabletohaveanundulyhighproportionof l00mesh 150 m material Usuallyamixtureoforefinesisused 2 Fuel normally 1 8in 3mm cokebreeze fineanthraciteissometimesused 3 Blast furnacefluedust 4 Flux limestoneand ordolomite 1 8in 3mm Otheradditives converterdust borings turnings etc aresometimesused 1 2 1 2Proportioningofrawmaterials Section Agglomeration Therawmaterialsmaybeblendedbylayingthemdownandreclaimingthemfrombedsoutsidethesinterplantproper ortheindividualcomponentsmaybestoredseparatelyandconveyedtoseparatebunkersinthesinterplant Fromthesebunkersthevariousmaterialsarewithdrawnviafeeders oftenassociatedwithdevicestoensurethatthefeedrateismaintainedconstant andcollectedonagatheringbelt Sometimesalltherawmaterials includingfluedustandfuel arecollectedonthesamebelt andsometimestheorefines fluedust andcokebreezearecollectedseparately 1 2 1 2Proportioningofrawmaterials Section Agglomeration Theproportionedrawmaterialsarenextmixedandmoistened Thisisusuallydonebypassingthemthroughadrumfittedwithpaddles waterbeingaddedtoimpartpermeabilitytothemixedmaterials Afterthisinitialmixing themoistmixmayberolledinadrumtogiveincreasedpermeability 1 2 1 3Mixing Section Agglomeration Themixisnowreadytobeloadedontothestrand Theaimistolaydownthematerialevenlyacrossthewidthofthestrandwiththeminimumofcompacting Anumberofmeanshavebeendevisedforeffectingthis forexampleaswingingspout arollfeederandavibrating trayfeeder Insomesinterplantsathinlayerofinertmaterial suchassizedsinter isfirstlaidonthegratebarsandthesintermixisloadedontopofthishearthlayer Immediatelyafterloadingthesurfaceofthemixislevelledbypassingitunderaplate the cut offplate whichissetsoastogivethedesiredthicknessofmixonthestrand Normallythisisbetween12and18in 300 450mm 1 2 1 4Loadingthemixontothestrand Section Agglomeration Nextthemixisignitedbymeansofgasoroilburners Normallytheburnersaresetinabrick linedhoodwhichcoversalengthofstrand butverticalburnerswhichimpingedirectlyontothemixaresometimesused 1 2 1 5Igniting 耐火砖衬里的炉罩 Section Agglomeration Thereaftersinteringproceeds airbeingsuckedthroughthebedintowindboxessituatedunderthegrate Thegrateconsistsofanumberofindividualpallets Thesepalletstravelforwardonwheelsrunningonatrackbesidethestrand andthesystemissealedasfaraspossibleagainstleakageofairinatthegrateedge Thestrandmovesforwardatabout10feet 3m perminutesothatthemixtakesabout15minutestotravelfromtheignitertotheendofthestrand Duringthistimethecombustionzonetravelsthroughthebed thestrandspeednormallybeingadjustedsothatcombustionofthefuelatthebottomofthebediscompletejustbeforethesinterreachestheendofthestrand 1 2 1 6Sintering Section Agglomeration Atthispointthefinishedsinteristippedfromthestrandasthepalletsturnfortheirjourneybacktotheloadingend Thesinterfallsontoacrashdeckandthelargelumpsarebrokenupbytoothedwheels Thedischargedsinterishot butvaryingintemperatureaccordingtoitspreviouspositioninthebed thesinterfromthetopofthebedhasalreadybeencooledtoambienttemperature whereasthatfromthebottomofthebedisover1850 1000 Fromthecrashdeckthesintermovestoavibratingscreen normallysetatabout3 8in 9mm Theundersize thereturnfines goesbacktojointhestreamofrawmaterialsandtheoversizegoesforwardtothesintercooler 1 2 1 7Sintertreatment Section Agglomeration Varioustypesofcoolerareused butinallcasestheprincipleisthesame Thescreenedsinterislaiddowninabedandairissuckedorblownthroughit Sincethesinterisnowfreeoffines thebedpermeabilityishighandthepowerrequirediscomparativelylow Aftercooling itisnormaltorescreenthesinterandreturntheundersize typically 5 16in 8mm totherawmaterialsystem 1 2 1 7Sintertreatment Section Agglomeration Suctionuptoabout50in watergauge 12kN m2 isappliedtothebottomofthesinterbedbymeansofaseriesofwindboxes Theseareconnectedtoawindmainbymeansofaseriesofdowncomers Thegasissuingfromthebedhasahighdustcontent Thecoarsedustsettlesoutandisremovedfromthemainbymeansofcounter weighteddustvalves whilethefinedustisremovedbymechanicalmeansorbyelectrostaticprecipitators Themainsinteringfanhandlesthecleangas whichisfinallydischargedtotheatmospherethroughastack 1 2 1 8Wastegassystem Section Agglomeration Thelayoutofatypicalshaft kilnpelletizingplantisshowninFigure1 5 Theoperationsinvolvedareasfollows l preparationoforefeed 2 balling and 3 hardening 1 2 2Pelletizing Section Agglomeration Typicallythefeedtoapelletizingplantiswetconcentrate Frequentlytheconcentratesareregroundtoabout80percent 350mesh 44 m beforetheyarepelletized Theconcentrateslurryisthenthickenedandfilteredtoprovidematerialwiththedesiredmoisturecontent thisisnormallyaround10percent Atthisstageasmallquantity 0 5 1percent ofbentoniteisoftenmixedwiththemoistconcentrate Partialdryingissometimesneeded thiscanbeachievedeitherbyheatingorbymixingaproportionofdryfineswiththewetm