Numerical study of the effect of the inlet gas distributor on the bubble distribution in a bubbling fluidized bed

GasbubbledistributionisconsideredoneofthemostcriticalfactorsaffectingtheIndustrialFluidCokingTMprocesssinceitinfluencestheformationofwetagglomeratesthatcausesfoulinginthestrippersection.Amulti-phaseEulerian-Euleriantwo-fluidmethod(TFM)coupledwiththekinetictheoryofthegranularflow(KTGF)wasusedtoinvestigatethehydrodynamicsofabubblingfluidizedbed;thegoalistoincreasetheflowofgasbubblesintothefirsthalfofthejetcavityformedwhenliquidissprayedintothefluidizedbed,thusreducingtheformationofwetagglomerates.Thenumericalsimulationsunderdifferentsuperficialgasvelocities,differentgasdistributorgeometries,anddifferentgasdistributorinclinedangleswerecarriedout.Theresultsshowedthatthepredictedbubbledistributionsattheinjectionlevelunderthelabandcommercialoperatingconditionsaresimilaralthoughtheparticlesandgasesaredifferentunderthosetwooperatingconditions.Moregasbubblescanbedirectedtothefirsthalfofthejetcavitybyeitherincreasingthegassuperficialvelocity(directingaround20%moregastothespecifiedarea)orusingtheproposednewgasdistributor(directingaround30%moregastothespecifiedarea).Theeffectoftheinletgasdistributorconfigurationonthebubbledistributionismuchmoresubstantialwhentheinclinedangleofthegasdistributorislarge. (c) 2021InstitutionofChemicalEngineers.PublishedbyElsevierB.V.Allrightsreserved.

Automated summary

Gas bubble distribution is crucial in the Industrial Fluid CokingTM process to reduce the formation of wet agglomerates. By adjusting the gas superficial velocity or using a new gas distributor, more gas bubbles can be directed into the specified area. The configuration of the inlet gas distributor has a substantial impact on bubble distribution, especially when the distributor's inclined angle is large.