Royal Belgian Institute of Marine Engineers

Thegloballimitonsulfurof0.5%showntobeimplementedin2020willbereviewedanddecidedonin2018.Thechangemaybedelayeduntil2025. Figure2showsdesignatedorpending

ECAs.NotethatportswillbeincludedintheECA.

Emission control areas   In order to comply withMARPOL AnnexVI, ships travelling in designated ECAswillbeforcedtooperateusingmarinegasoil (MGO)/marine diesel oil (MDO)/lowsulfur fuel oil (LSFO) or by using anexhaustgascleaningsystem. IndesignatinganECA,theIMOdefines

certainareasoftheseasandinlandwaterwaysas'specialareas'inwhich,fortechnicalreasonsrelatingtotheirecologicalconditionandseatraffic,theadoptionofmandatorypollutionpreventionisrequired.UndertheConvention,thesespecialareasareprovidedwithahigherlevelofprotection

than otherareasofthesea.AnnexVIECAzones,bothexistingandpending,canbeseeninFigure2.NotethatsulfurrulesaresupportedbyEUandUSEPAregulatorsandenforcementwillbecarriedoutbyvariousgovernmentalorganisations. TheimplementationdatesfortheECAzonesvary.EnforcementintheBalticECAbeganinMay2006,intheNorthSeaECAinNovember2007,intheNorthAmericanECAinAugust2012andintheNorthAmericanCaribbeanECAinJanuary2012.Futurecontrolareasunderconsiderationinclude

theMediterraneanandtheFarEast.

The ripple effect   MARPOLAnnexVIwillhavefarreachingconsequencesforrefiners.Forthevastmajorityofshippers,thesimplestcompliancesolutionistoswitchtoburninglowsulfurfuelinlieuofthehighersulfurfuelscurrentlyused.Thiswillimpactthepricesofbothlowandhighsulfurfuelsinaninverseway.Itisexpectedthatwhentheregulationstakeeffectasearlyas1stJanuary,2015,demandforMGO/MDO/LSFOwillincrease,drivingpricestorecordhighsbasedonincreaseddemandandcreatingshortages,whilethepriceofhighsulfurfueloil(HSFO)willdecreasetoaverylowpricecomparedtocurrentpricelevels. Arecentstudyindicatesthedifferentialbetweenmarinebunker

andgasoilcouldreachUSS450/tin2015andclimbsteadilyincomingyears,reachingUSS500/tin2020andUSS600/tin2030.Thefuturedifferentialcouldbehigher.ForsomeshipsthatareparticularlyactiveintheECAs,highMGO/MDO/LSFOpriceswillbeuntenable. Thecoststotherefineryforincreasingproductionoflowersulfurfuelstomeetthenewmarinedemanddrivenbytheseregulationswouldbeastronomical.Inaddition,therequiredrevampstorefinerieswouldtakeyears.Currently,itdoesnotappearthatanyrefinershavegivenmuchconsiderationtomodifyingtherefinerytomeettheincreasedLSFOdemand.

Engineering clean air on land and at sea   Manysimilaritiescanbedrawnbetweentherefineryscrubberapplicationandthemarineapplication,thoughthemarineapplicationissomewhatlessdemanding.

Inadditiontosimilarprocessconditionsfacedinrefineriesandonships,ofutmostconcerninbothindustriesisreliability.Therefineryscrubberneedstobeextremelyreliableespeciallywheninstalledonthefluidcatalyticcrackingunit(FCCU).ScheduledturnaroundsfortheFCCUare4‐6years,andthescrubbermustbeoperableduringthisperiodtomatchtheturnaroundschedule.SincetheFCCUistheheartoftherefinery,unscheduledturnaroundscancosttherefinerymillionsofdollarsinlostprofit.

Marinescrubbingtechnologyalsoneedstobereliable,anditisnosmalltasktodesignasystemthatisrobust,highquality,andsleekenoughtoaccommodatethetightspacesavailableonships,yetaffordableenoughtomeetareasonablepaybackperiod.BELCO®scrubbertechnologyisabletoachievethat.

BELCO®refineryandmarinescrubbersuseanopentowerwithspraydesign,asopposedtotheuseofpackingtotrapparticlesanddroplets.Packingisavoidedduetothepotentialofpluggingfrombuildupofparticulateandsootaswellasotherreasons.Inthemarinespace,somecompaniesofferpackingdesignswhichusenon‐metallicmaterials(plasticorglassfibrereinforcedplastic(GRP)whichcanmeltorevencatchfireduringmaintenance.Packingalsocausesthe

Scrubbing technology: from land to sea   Asrefinerymanagersaroundtheglobeconcernedaboutsulfuremissionshavecometoknow,sulfuremissionmanagementcanbeachievedcosteffectivelythroughwetfluegasscrubbing.FluegasscrubbingtechnologythathasbeenusedsuccessfullyfordecadesonrefiningfluidcatalyticcrackersandboilerscanbeeffectivelymodifiedtoabsorbSOxfrommarineengineandboilerexhaustgases.Wetscrubbingcaneffectivelyreducesulfuremissionstolessthantheequivalent0.1%sulfurcontentrequirement.Notonlyhaswetscrubbingbeensuccessfullyutilisedonhundredsofrefiningapplications,ithasalsobeeneffectivelymeetingIMOsulfuremissionstandardsondozensofclasscertifiedmarineapplications.

Shipboardscrubbersaretheeconomicallyviable,lowoperatingexpenditure(OPEX)alternativetoburningultralowsulfurfuels.TheycanbeinstalledwithapaybackperiodoflessthantwoyearswhilemeetingallIMOequivalentsulfuremissionslimits.Marinescrubbersrepresentacompliancealternativethatwouldallowrefinerybusinessestocontinuebenefittingfromtheirexistingrefiningprocessbunkerproduction,whileallowingshipstobeinfullcompliance.AstheJanuarydeadlinefastapproaches,itseemseveryweekannouncementsarecomingoutnamingnewcontractsbetweenscrubbercompaniesandferry,cruiseshipsandcargovessels.

Withnoincreaseinsupplyofthesefuels,thelowersulfurfuelswillbeingreatdemand,drasticallyincreasingthefuelprice.TheIMOaswellastheEUhavesaidtheywillnotpostponethecompliancedates.Henceitisuptosavvyshipownerstolookforalternativewaystoeconomicallycomplywiththenewregulationsoutsideofjustswitchingtolowsulfurresidualanddistillatefuels. Othercomplianceoptionseachcomewiththeirshareoffinancial,technicalandoperationalchallenges.InthelongertermalternativessuchasLNG,biofuels,dimethylether(DME)andmethanolmayprovidesolutions.However,moreandmoreshipsareadoptingexhaustgascleaningsystems(EGCS)toabsorbSOxoutofexhaustgastotherequired0.1%Sequivalent.TheEGCSofferstheflexibilitytooperateonanykindofbunkerbothinandoutofECAs.

scrubberdiametertobelargerasthegasvelocityacrossthepackingneedstobelowerthantheopentowertoincreasecontacttime.Packingalsocontributesadditionalweighthigherupintheshipfunnelwhichcanreduceaship'sstability,causingthevesseltobeunsteadyinroughseas.

TheBelcoscrubberutilisesabottominlet.Combinedwiththefactthatitismadeofhighquality,corrosionresistantmaterialsthatcanwithstandhightemperatures,thisallowstheshiptooperateina'rundry'modewithnoactivescrubbingwhenoutsideofECAs,eliminatingtheneedforabypassofthescrubber,andreducinginstalledcosts.Additionally,thereisnowaterretentioninthebottomofthescrubber.Thisnotonlyreducesweightbutpreventsanyscrubberwaterfromdrainingbacktotheengine,avoidingthepotentialofcausingmajorenginedamage.Thespecialbottominletextendsintothebottomofthescrubbertoavoidanywaterrunningintotheinletduct.Becauseofitsdesignharmonics,thescrubberisabletoeliminate/replacetheneedforanenginesilencer.

TheBelcoMarineScrubbercanoperateinthreedifferentmodes:openloop,closedloopordry.Inopenloopoperation,thescrubberusesonlyseawaterononcethroughpassforscrubbing.Theopenloopscrubbercanonlybeusedwherethereisenoughalkalinityintheseawater.Inclosedloopoperation,thescrubberliquidisnotusedonaoncethroughbasisbutisrecycledand'dosed'withanalkalinereagentsuchascausticinordertoreducetheamountofSOxintheexhaustgastomeettherequiredoutlet.Theclosedloopsystemisusedwherethereisnotsignificantalkalinityinthewaterforopenloopscrubbing,suchasinfreshwaterlakes,riversandareasintheBaltic(oranyotherbodyofsaltwaterwhichhaslowalkalinity)orwherethereareregulationsorotherreasonsfornotbeingabletodischargethescrubbereffluent(oftenreferredtoaswashwater).Indrymode,hotexhaustgasesexittheshipthroughthescrubbervessel.Thescrubberisoffandthereisnoemissioncontroltakingplace.DrymodealsoallowstheBelcoMarineScrubbertobeinstalledwithoutabypass.AshipwouldtypicallyoperateindrymodewhentravellingoutsideofanECA.

Ascrubbingsystemcanbeprovidedwhichcanoperateinanyofthethreemodes,andthereforeinanymaritimeenvironment.ThissystemisreferredtoastheBELCOMS‐Hybridandcontainsalloftheequipmentandinstrumentationforeithermodeofscrubbingorrundry. Conclusion   ItisunlikelythatinvestmentinrefiningprocessesneededtomeettheultralowsulfurmarinefueldemandsimposedbyMARPOLAnnexVIregulationswillbemade.Forshipstotakeadvantageofavailablefuelregardlessofsulfurcontentandstillmeettheregulations,anexhaustgascleaningsystem,orscrubber,isanincreasinglypopularoption.BasedontheamountoftimeashipspendsinanECA,currentfuelpricedifferentials,amountoffuelconsumed,scrubbercosts,andothervariables,ashipoutfittedwithascrubbercanhaveapaybackperiodofl.5to3years.Withthefuelpricedifferentialsincreasing,thepaybackperiodcanevenbeshorter.

Source:Hydrocarbonengineering–August2014