04EPOXSU-ABNORM-519

NOTE:ThisisforTrainingonly,andisnotintendedtobeusedasastepbystepprocedure.PO/MTBEEPOXIDATIONABNORMALOPERATINGPHENOMENONNOTE:ThisisforTrainingonly,andisnotintendedtobeusedasastepbystepprocedure.PO/MTBEEpoxidationAbnormalOperatingPhenomenonPropyleneRecoverySystemAbnormalPhenomenonThepurposeofthisdocumentistoidentifytheabnormalphenomenonassociatedwiththePropyleneRecoverySystemandthestepstakentorectifythephenomenon.HighPressureonPropyleneRecoveryColumn:•Checkforfreezingonoverheadcondenser01E0229.EnsureEGinjectionmakeuptooverheadcondenserislinedup.Checkflowandensureadequateflowisobservedontheflowindicator,iflowornoflowisobservedthenlineupEGorincreaseflowtocondensertothawout.HighPressureonPropyleneRecoveryColumn:•Checkforfreezingonoverheadventcondenser01E0299.EnsureEGinjectionmakeuptooverheadventcondenserislinedup.Checkflowandensureadequateflowisobservedontheflowindicator,iflowornoflowisobservedthenlineupEGorincreaseflowtocondensertothawout”.NOTE:ThisisforTrainingonly,andisnotintendedtobeusedasastepbystepprocedure.PO/MTBEPropyleneRecycleSystemAbnormalPhenomenonThepurposeofthisdocumentistoidentifytheabnormalphenomenonassociatedwiththePropyleneRecycleSystemandthestepstakentorectifythephenomenon.Hydrocarbonsinthecoolingwatersystem:•CheckforVOCsonbleederatcoolingwaterreturnlinefromoverheadcondenser.IfanyhydrocarbonisdetectedonthecoolingwaterreturnlinethenthePropyleneRecycleColumnmustbebypassedandshutdownforrepairs.FollowproperprocedurestobypassPropyleneRecycleColumnandthenfollowproperprocedurestoshutdownPropyleneRecycleColumn.WhenthiscolumnisbypassedthepropanecontenttotheEpoxidationFeedbecomeselevatedwithpropanecausingoperatingissues.SeeEpoxidationSystemAbnormalPhenomenonformoreinformation.EpoxidationAbnormalOperatingPhenomenonNOTE:ThisisforTrainingonly,andisnotintendedtobeusedasastepbystepprocedure.PO/MTBEPropyleneRecycleSystemAbnormalPhenomenoncont’d.HighColumnBottomsLevelorlossofColumnBottomsTemperature:•ThisisnormallycausedwhenPOhasbeencarriedovertothePropyleneRecycleColumnfromthePropyleneRecoveryColumnduetooperationupset.POinthebottomsofthePropyleneRecycleColumnwillcausefoulingofthereboilerandthenwillneedtobeshutdownandcleanedforpropercolumnoperation.BypassthePropyleneRecycleColumnbyproperoperatingprocedures.EpoxidationAbnormalOperatingPhenomenonNOTE:ThisisforTrainingonly,andisnotintendedtobeusedasastepbystepprocedure.PO/MTBEEpoxidationSystemAbnormalPhenomenonThepurposeofthisdocumentistoidentifytheabnormalphenomenonassociatedwiththeEpoxidationSystemandthestepstakentorectifythephenomenon.NormalButaneintheIsobutaneFeed:•ThisconditionoccurswhennormalbutanecompoundsareintheIC4feedtothePeroxidationReactors.OxygenmustbereduceddramaticallytopreventhigherthannormaltemperaturesandhigherthannormalpressuresonthePeroxidationReactors.ThisconditionwillcausehigherthannormalacidstobeformedandcarriedwiththeTBHPtotheTBHPStorageTankthatfeedstheEpoxidationReactors.ThemoreorhigheracidformationintheTBHPfeedtotheEpoxidationReactorsleadstomoreimpuritiesbeingformedintheEpoxidationprocess.ThiswillcauselowerproductionofPOandanincreaseinimpuritiesthatmustberemovedinthePOPurificationSystem.AvoidnormalbutanecompoundsintheIsobutanefeedtothePeroxidationReactors.EpoxidationAbnormalOperatingPhenomenonNOTE:ThisisforTrainingonly,andisnotintendedtobeusedasastepbystepprocedure.PO/MTBEEpoxidationSystemAbnormalPhenomenoncont’d.PropaneinthePropylenefeed:•ThisconditionoccurswhenpropanecompoundsareinthepropylenefeedtotheEpoxidationReactors.ThisoccurswhenthePropyleneRecycleColumnmustbebypassedwhiletheplantisonlineandrepairsmustbemadetothePropyleneRecycleColumn.ThepropanenormallyrejectedoffthebottomofthePropyleneRecycleColumnnowcarriestothePropyleneFeedDrumintheEpoxidationReactorSystemanddoesnotreactwellwiththeTBHP/Catalyst.ContinuedforwardprocessallowspropanetobuildupintheEpoxidationReactorsystemandreducesPOproduction.AvoidpropanecompoundsinthePropylenefeedtotheEpoxidationReactors.ExtendedreducedtotalfeedratestotheEpoxidationSystem:•Ifconditionsexistofextendedreducedfeedrateslowerthanapprox.70%ofcapacitythenadditionalTBAmustbeaddedtotheSecondStageEpoxidationReactorSystem.ThisadditionalTBAcanbeaddedattheTBAFlushcontrolvalvethatisconnectedtotheSecondStageEpoxidationReactorSystem.ThisadditionalTBAwillaidinthefeedratetotheTBARemovalColumnandmaintainfeedratestothatsectionoftheplant.EpoxidationAbnormalOperatingPhenomenon