简介:Ore-cokemixedchargingisapotentialtechniqueforoptimizingthechargingpattern.Recently,thechargingofsmall-sizedcoke(nutcoke)withtheferrousburdenlayerhasbeenappliedtoreducerawmaterialusageanddecreasecosts.Variousstudiesindicatethatmixingnutcokewithferrousburdencanenhancethereductionkinetics,improvethesofteningandmeltingproperties,andhaveapositiveeffectonthepermeability.Althoughmixedcharging,especiallytheadditionofnutcoketotheburdenlayer,hasbeenusedintheindustryforvariousreasons,themechanismsandsideeffectsforusingnutcokearenotwellunderstood,andthemixingratioremainslimitedinactualblastfurnaceoperation.High-temperatureexperimentalstudieswereconductedtoincreasetheunderstandingofthecomplexprocessofreduction,softeningandmeltingproperties,andpermeabilityinablastfurnacewhenmixingnutcokewithanorelayer.Theeffectofthenutcokemixingratioandnutcokesizewasinvestigatedundervariousreducingconditions.Todescribethereductionprocessesofburdenmaterials,numerousexperimentswereinterruptedatdifferentstagesofthereduction,andthecollectedmaterialswereexaminedbyusingimageanalysis.Thereductiondegreeofmixedcharging(ironoremixingwithnutcoke)wasimprovedwhenusingnutcokeatthetemperaturesof800℃andabove.Thereactionrateofore-nutcokemixedchargingwashigherthanthatofstandardchargingwithouttheuseofnutcoke.