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SpecializedEnglishforchemistryChemicalEnineeringandTechnologyLesson2TheAnatomyofaChemicalManufacturingProcess•ThebasiccomponentsofatypicalchemicalprocessareshowninFig.6-2-1,inwhicheachblockrepresentsastageintheoverallprocessforproducingaproductfromtherawmaterials.•Fig.6-2-1representsageneralizedprocess,notallthestageswillbeneededforanyparticularprocessandthecomplexityofeachstagewilldependonthenatureoftheprocess.•Generalized广泛的;普遍的;非具体的;整体的RawMaterialstorageFeedpreparationReactionProductseparationProductpurificationProductstorageSalesStage1Stage2Stage3Stage4Stage5Stage6RecycleofunreactedmaterialBy-productsWastes•Chemicalengineeringdesignisconcernedwiththeselectionandarrangementofthestages,andtheselection,specificationanddesignoftheequipmentrequiredtoperformthestagefunctions.•Arrangement安排，料理，筹备，预备;整顿，整理，排列，布置，分类;商定，约定;调解，和解•Specification规格;详述;说明书•Stage1Rawmaterialstorage•Unlesstherawmaterials(alsocalledessential,orfeedstocks)aresuppliedasintermediateproducts(intermediates)fromaneighboringplant,someprovisionwillhavetobemadetoholdseveralday’sorweek’sstoragetosmoothoutfluctuationsandinterruptionsinsupply.•Essential基本的;必要的;本质的;精华的•Feedstocks原料•Fluctuations波动，涨落，起伏(fluctuation的名词复数)•Interruptions中断(interruption的名词复数);打断;障碍物;打岔的事•Evenwhenthematerialscomefromanadjacentplant,someprovisionisusuallymadetoholdafewhours,orevenafewdays,supplyingtodecoupletheprocesses.•Adjacent邻近的，毗邻的;（时间上）紧接着的;相邻;•Decouple减弱•Thestoragerequiredwilldependonthenatureoftherawmaterials,themethodofdelivery,andwhatassurancecanbeplacedonthecontinuityofsupply.•Ifmaterialsaredeliveredbyship(tankerorbulkcarrier),severalweeks’stockmaybenecessary;•iftheyarereceivedbyroadorrail,insmallerlots,lessstoragewillbeneeded.•Lots份额;许多•Stage2Feedpreparation•Somepurificationandpreparationoffilerawmaterialswillusuallybenecessarybeforetheyaresufficientlypure,orintherightform,tobefedtothereactionstage.•Forexample,acetylenegeneratedbythecarbideprocesscontainsarsenicalandsulphurcompounds,andotherimpurities,whichmustberemovedbyscrubbingwithconcentratedsulphuricacid(orotherprocesses)beforeit’ssufficientlypureforreactionwithhydrochloricacidtoproducedichloroethane.•Acetylene乙炔，电石气•Carbide碳化物;硬质合金•arsenical砷的，含砒素的;砷剂•Sulphur硫•Hydrochloricacid盐酸•Dichloroethane二氯乙烷;•Liquidfeedswillneedtobevaporizedbeforebeingfedtogas-phasereactorsandsolidsmayneedcrushing,grindingandscreening.•Vaporized（使）蒸发，（使）汽化(vaporize的过去式和过去分词)•Crushing压破，压碎;镇压;弄皱;挤榨，榨出•Grinding磨碎，嚼碎;折磨•Screening筛（煤、矿石等）(screen的现在分词)•Stage3Reaction•Thereactionstageistheheartofachemicalmanufacturingprocess.•Inthereactor,therawmaterialsarebroughttogetherunderconditionsthatpromotetheproductionofthedesiredproduct;invariably,by-productsandunwantedcompounds(impurities)willalsobeformed.•Invariably总是;不变的;“invariable”的派生;无不•Stage4Productseparation•Inthisfirststagealteringthereactortheproductsandby-productsareseparatedfromanyunreactedmaterials.•Ifinsufficientquantity,theunreactedmaterialswillberecycledtothereactor.•Theymaybereturneddirectlytothereactorortothefeedpurificationandpreparationstage.•Theby-productsmayalsobeseparatedfromtheproductsatthisstage.•Stage5Purification•Beforesale,themainproductwillusuallyneedpurificationtomeettheproductspecification.•Specification规格•Ifproducedineconomicquantities,theby-productsmayalsobepurifiedforsale.•Stage6Productstorage•Someinventoryoffinishedproductsmustbeheldtomatchproductionwithsales.•Inventory存货清单;财产目录，财产目录的编制;存货总值;清查•Provisionforproductpackagingandtransportwillalsobeneeded,dependingonthenatureoftheproduct.•Liquidswillnormallybedispatchedindrumsandinbulktankers(road,railandsea),solidsinsacks,cartonsorbales.•Dispatched分装•Sack麻袋•Carton纸箱•Bale包•Thestackheldwilldependonthenatureoftheproductandthemarket.•Stack堆成堆，垛;堆起来或覆盖住;•1Ancillaryprocesses•Ancillary辅助的;补充的;附属的;附加的•InadditiontothemainprocessstagesshowninFig6-2-1,provisionwillhavetomadeforthesuppyoftheservices(utilities)needed,suchasprocesswater,coolingwater,compressedair,steam.•Facilitieswillalsobeneededformaintenance,firefighting,officesandotheraccommodation,andlaboratories.•Maintenance维护，维修•Firefighting消防•Accommodation住处;适应;便利;和解•Laboratories实验室•2Continuousandbatchprocesses•连续和间歇过程•Continuousprocessesaredesignedtooperate24hoursaday,7daysaweek,throughouttheyear.•Somedowntimewillbeallowedformaintenanceand,forsomeprocesses,catalystregeneration.•Theplantattainment,thatis,thepercentageoftheavailablehoursinayearthattheplantoperates,willusuallybe90%to95%.•Batchprocessesaredesignedtooperateintermittently.•Intermittently间歇地;断断续续•Someoralltheprocessunitsarefrequentlyshutdownandstartedup.•Continuousprocesseswillusuallybemoreeconomicalforlargescaleproduction.•Batchprocessesareusedwheresomeflexibilityiswantedinproductionrateorproductspecification.•Flexibility柔韧性，机动性，灵活性;伸缩性;可塑度;柔度;•Thechoicebetweenbatchandcontinuousoperationwillnotbeclearcut,butthefollowingrulescanbeusedasaguide.ContinuousBatch1.Productionrategreaterthan5*100kg/h1.Productionratelessthan5*100kg/h2.Singleproduct2.Arangeofproductsorproductspecifications3.Noseverefouling3.Severefouling4