《工业分析 Industrial Analysis》课件-燃烧-气体容量法测定钢铁中碳（双语）

项目六：钢铁分析任务二：钢铁中碳的测定燃烧-气体容量法测定钢铁中碳课程：工业分析中文Scenario6:SteelanalysisTask2:DeterminationofcarboninsteelDeterminationofcarboninsteelbycombustiongasvolumetricmethodCourse:IndustrialAnalysisEglish1、方法原理试样在1200～1300℃的高温O2气流中燃烧，钢铁中的碳被氧化生成CO2:C+O2=CO24Fe3C+13O2=4CO2+6Fe2O3

Mn3C+3O2=CO2+Mn3O3FeS+5O2=Fe3O4+3SO23MnS+5O2=Mn3O4+3SO2中文1、Methodprinciple

ThesampleburnsinanO2airflowathightemperaturesrangingfrom1200to1300℃,andthecarboninthesteelisoxidizedtoproduceCO2:C+O2=CO24Fe3C+13O2=4CO2+6Fe2O3

Mn3C+3O2=CO2+Mn3O3FeS+5O2=Fe3O4+3SO23MnS+5O2=Mn3O4+3SO2Eglish生成的CO2与过剩的O2经导管引入量气管，测定容积，然后通过装有KOH溶液的吸收器，吸收其中的CO2CO2十2KOH=K2CO3十H2O剩余的O2再返回量气管中，根据吸收前后容积之差，得到CO2的容积，据此计算出试样中碳的质量分数。中文

First,introducethegeneratedmixtureofCO2andexcessO2intothevolumetrictube,measurethevolumeofthemixture,andthenintroducethemixtureintoanabsorbercontainingKOHsolutiontoabsorbtheCO2inside:

CO2+2KOH=K2CO3+H2O

TheremainingO2isreturnedtothemeasuringtube,andbasedonthedifferenceinvolumebeforeandafterabsorption,thevolumeofCO2isobtained.Basedonthis,themassfractionofcarboninthesampleiscalculated.Eglish图

气体容量法定碳装置1-氧气瓶，2-氧气表，3-缓冲瓶，4、5-洗气瓶，6-干燥塔，7-玻璃磨口塞，8-管式炉，9-燃烧管，10-除硫管，11-容量定碳仪(包括:冷凝管a、量气管b、水准瓶c、吸收瓶d、小旋塞e、三通旋塞f），l2-球形干燥管，13-瓷舟，14-温度自动控制器，15-供氧旋塞2、测定仪器中文2、measuringinstrumentGasCapacityCarbonizationDevice1-Oxygencylinder,2-Oxygenmeter,3-Buffercylinder,4,5-Washingcylinder,6-Dryingtower,7-Glassgrindingplug,8-Tubefurnace,9-Combustiontube,10-Sulfurremovaltube,11-Capacitycarbonanalyzer(includingcondensertubea,measuringtubeb,levelbottlec,absorptionbottled,smallcocke,three-waycockf),12-Sphericaldryingtube,13-Porcelainboat,14-Temperatureautomaticcontroller,15-OxygensupplycockEglish3、测定试剂氢氧化钾吸收剂溶液（400g/L）；除硫剂活性二氧化锰（粒状）或钒酸银；酸性氯化钠溶液（250g/L）；助熔剂：锡粒（或锡片）、铜、氧化铜、纯铁粉；高锰酸钾溶液（40g/L）；甲基橙指示剂（2g/L）。中文3、TestingreagentsPotassiumhydroxideabsorbentsolution(400g/L);Sulfurremovalagent:activemanganesedioxide(granular)orsilvervanadate;Acidicsodiumchloridesolution(250g/L);Fluxes:tinparticles(ortinsheets),copper,copperoxide,pureironpowder;Potassiumpermanganatesolution(40g/L);Methylorangeindicator(2g/L).Eglish4、测定步骤将炉温升至1200～1350℃，检查管路及活塞是否漏气，装置是否正常，燃烧标准样品，检查仪器及操作。称取适量试样置于瓷舟中，将适量助熔剂覆盖于试样上面，打开玻璃磨口塞，将瓷舟放入瓷管内，用长钩推至高温处，立即塞紧磨口塞。预热lmin，按照定碳仪操作规程操作，测定其读数(体积或含量)。打开磨口塞，用长钩将瓷舟拉出，即可进行下一试样分析。中文4、Measurementsteps

Raisethefurnacetemperatureto1200-1350℃,checkforleaksinthepipelinesandpistons,ensurethedeviceisfunctioningproperly,burnstandardsamples,andinspectinstrumentsandoperations.

Weighanappropriateamountofsampleandplaceitinaporcelainboat.Coverthesamplewithanappropriateamountofflux,opentheglassgrindingplug,placetheporcelainboatintotheporcelaintube,usealonghooktopushittoahightemperature,andimmediatelytightenthegrindingplug.Preheatforlmin,followtheoperatingproceduresofthecarbonanalyzer,andmeasureitsreading(volumeorcontent).Openthegrindingplugandpullouttheporcelainboatwithalonghooktoproceedwiththenextsampleanalysis.Eglish5、测定注意事项助熔剂中含碳量一般不超过0.005%样品的放置要均匀地铺在燃烧舟中定碳仪应装置在室温较正常的地方(距离高温炉约300～500mm)更换水准瓶所盛溶液、玻璃棉、除硫剂、氢氧化钾溶液后，均应作几次高碳试样，使二氧化碳饱和后，才可进行试样测定。中文5、MeasurementprecautionsThecarboncontentinthefluxgenerallydoesnotexceed0.005%ThesampleshouldbeplacedevenlyinthecombustionboatThecarbonanalyzershouldbeinstalledinaplacewithrelativelynormalroomtemperature(about300-500mmawayfromthehigh-temperaturefurnace)Afterreplacingthesolution

inthelevelingbottle,glasswool,sulfurremovalagent,andpotassiumhydroxidesolution,severalhighcarbonsamplecombustionshouldbecarriedouttosaturatecarbondioxideinthesesubstancesbeforesampledeterminationcanbecarriedout.Eglish对测定含硫量较高的试样(大于0.2%)，应增加除硫剂量或增加一个除硫管。吸收器、水准瓶内溶液以及混合气体三者的温度应基本相同，否则将产生正负空白值。如分析完高碳试样后，应空烧一次，才可以接着做低碳试样分析。当洗气瓶中硫酸体积显著增加及二氧化锰变白时，说明已失效，应及时更换。观察试样是否完全燃烧，如燃烧不完全，需重新分析。中文Forsampleswithhighsulfurcontent(greaterthan0.2%),thesulfurremovaldoseshouldbeincreasedorasulfurremovaltubeshouldbeadded.Thetemperatureoftheabsorber,thesolutioninthelevelbottle,andthemixedgasshouldbebasicallythesame,otherwisepositiveandnegativeblankvalueswillbegenerated.Afteranalyzingthehighcarbonsample,itshouldbeburnedoncebeforeproceedingwiththeanalysisofthelowcarbonsample.Whenthevolumeofsulfuricacidinthegascylindersignificantlyincreasesandmanganesedioxideturnswhite,itindicatesthatithasfailedandshouldbereplacedinatimelymanner.Observewhetherthesampleiscompletelyburned.Ifthecombustionisincomplete,reanalysisisrequired.Eglish炉子升温应开始慢，逐步加速，以延长硅碳棒寿命。分析前，应先检查仪器各部分是否漏气。工作开始前及工作中，均应燃烧标准样品，判定工作过程中仪器的准确性。吸收前后观察刻度的时间应一致。吸收后观察刻度时，量气管及水准瓶内液面与视线应处在同一水平线上。吸收器中氢氧化钾溶液使用久后也应进行更换，一般在分析2000次后更换，否则吸收效率降低，使测定结果偏低。测定中应记录温度与大气压力，以确定补正系数f。如附录八所示。中文Theheatingofthefurnaceshouldstartslowlyandthengraduallyacceleratetoextendthelifespanofthesiliconcarbiderod.Beforeanalysis,eachpartoftheinstrumentshouldbecheckedforairleakage.Beforeandduringwork,standardsamplesshouldbeburnedtodeterminetheaccuracyoftheinstrumentsusedduringtheworkprocess.Whenobservingthescaleafterabsorption,theliquidlevelinthemeasuringtubeandlevelbottleshouldbeonthesamehorizontalline.T