UNIVERSITÀ DEGLI STUDI DI PADOVA - unipd.ittesi.cab.unipd.it/53980/1/Calabretta_Saverio_tesi.pdf · UNIVERSITÀ DEGLI STUDI DI PADOVA Dipartimento di Ingegneria Industriale Corso

UNIVERSITÀDEGLISTUDIDIPADOVA

DipartimentodiIngegneriaIndustriale

CorsodiLaureaMagistraleinIngegneriaEnergetica

OptimizingtheimplementationofbiofuelsintheSwissenergyand

transportsectors

Relatore

Prof.ArturoLorenzoni

Correlatore

BrianCox

Studente

SaverioCalabretta1101778

AnnoAccademico2015/2016

2

3

AbstractThisthesisanalyzestheenvironmentalimpactsofdifferentbiofuels’productionpathways

andtheirsubsequentusageforpoweringdifferentmid-sizedcarsintheSwissterritory.

StartingfromtheavailablebiomassespresentinSwitzerlandwhicharemainlywood

biomass(fromtheforests,landscapemaintenanceandindustrialresidues),andanimal

waste.Algaebiomassisalsoconsideredeventhoughitisnotcurrentlypossiblecultivateit

inSwitzerlandwithhighyield,duetothenon-optimalweatherandlatitudeconditions,but

theproductionabroad(e.g.inItaly)andthefollowingimportationofthefinishedfuelshas

beenanalyzed.Differentprocesseshavebeeninvestigatedandthepathwaysexaminedare:

electricityfromacombinedheatandpowerplant(CHP)orfromanORC(OrganicRankine

Cycle)plant,hydrogenfromwoodgasification,gasolineandbiodieselfromfast-pyrolysisof

woodbiomass,orfromalgaeoilesterificationorhydrothermalliquefactionprocesses,and

theupgradeofbiogasandSNG(SyntheticNaturalGas)intomethanefromwoodbiomass

gasification,manureanaerobicdigestion,andwoodandmanurebiomasshydrothermal

gasification(HTG).Forreachingthegoalofthisstudythefunctionalunitforthebiofuels

productionhasbeensetequalto1MJ.

Thedifferentbiofuelsanalyzedhavebeenthenconsideredinpoweringdifferentmid-sized

cars,whosedatacomefromtheTHELMAproject.Inthisway,acomparisonamongthe

differentbiofuelsproducedandtheconventionalfossilfuelsorthedifferentelectricitymix

havebeenusedasreferences,inordertounderstandwhicharethemostpromising

pathwaysforpoweringavehicle.Forthispartofthethesisthefunctionalunithasbeenset

equalttoonevehiclekilometer(vkm),toallowthecomparisonofthedifferentvehiclesin

coveringonekilometer.

TheseprocessesaremodeledusingtheSimaProv8.04softwareusinginformationfrom

availableliterature,personalinterviewswithexpertsandscientists,andtheexisting

datasetsintheecoinventdatabase.

Theresultsobtainedsuggestthebestenvironmentalwaytoexploitthedifferentbiomass

resourcesforlightdutyvehiclesintheSwisstransportationsector.

4

TableofContents1. Introduction...............................................................................................................8

1.1 SwissSituation.............................................................................................................101.2 ResearchGoals.............................................................................................................13

2. LiteratureReview....................................................................................................152.1 LiteratureontheSwisssituation..................................................................................152.2 Papersdirectlyusedformodelingtheprocesses..........................................................172.3 Comparisontable.........................................................................................................21

3. Methodology...........................................................................................................223.1 LifeCycleAssessment(LCA).........................................................................................223.2 Scopeandgoaldefinition.............................................................................................223.3LifeCycleInventories(Collection)-LCI................................................................................233.4LifeCycleImpactAssessment(LCIA)...................................................................................243.5Interpretation.....................................................................................................................263.6 BiogenicEmissions.......................................................................................................263.7Base&OptimizedScenario.................................................................................................27

4. LCIoftheprocessesusingWoodBiomass................................................................304.1 WoodGasification&MethanationProcess-LCI...........................................................314.2 FastPyrolysisProcess-LCI...........................................................................................344.3 HydrothermalGasification–LCI...................................................................................384.4 CogenerationHeatandPowerPlant-LCI.....................................................................414.5 Hydrogenfromwoodgasification–LCI........................................................................43

5. LCIoftheprocessesusingmanurebiomass..............................................................455.1BiogasproductionandMethanation–LCI...........................................................................465.2BiogasEngineCo-generation–LCI.....................................................................................495.3HydrothermalGasificationofmanurebiomass–LCI...........................................................50

6.LCIofalgaeprocesses..................................................................................................546.1BiodieselfromOpenPondsRaces.......................................................................................576.2GasolinefromAlgae100hafacility.....................................................................................62

6.1.1WetSolventExtraction.......................................................................................................64

6.2.2HydrothermalLiquefactionprocess(HTL)OptimizedCase-LCI........................................66

6.2.3OpenAlgaeProcess(WetExtraction)Optimized-LCI........................................................68

6.2.4GasolineProcessesComparison.........................................................................................70

7. LifeCycleImpactAssessment&Results...................................................................727.1WoodPathways.................................................................................................................74

7.1.1GlobalWarmingPotential..................................................................................................74

7.1.2FreshWaterEutrophicationPotential................................................................................76

7.1.3ParticulateMatterFormationPotential.............................................................................78

7.1.4NaturalLandTransformationPotential..............................................................................80

7.2ManurePathways...............................................................................................................837.2.1GlobalWarmingPotential..................................................................................................83

5

7.2.2FreshwaterEutrophicationPotential..................................................................................85



7.3AlgaePathways..................................................................................................................907.3.1GlobalWarmingPotential..................................................................................................90

7.3.2FreshwaterEutrophicationPotential..................................................................................91



8.Discussion...................................................................................................................978.1 ComparisonwithEMPAstudy......................................................................................978.2 ComparisonwithotherLCAsonbiofuels......................................................................99

9.Conclusions...............................................................................................................1019.1CurrentScenario...............................................................................................................1019.2OptimizedScenario..........................................................................................................1039.3FinalConclusion................................................................................................................104

10. Acknowledgements............................................................................................106

11. Appendix...........................................................................................................107

12. References.........................................................................................................117

6

ListofAbbreviations

LCA–LifeCycleAssessment

SNG–SyntheticNaturalGas

WTT–WelltoTank

TTW–TanktoWheel

WTW–WelltoWheel

PSI–PaulScherrerInstitut

SCCER–SwissCompetenceCentersforEnergyResearch

BIOSWEET–Biomass

HTL–HydrothermalLiquefaction

HTG–HydrothermalGasification

FP–FastPyrolysis

FU–FunctionalUnit

PSA-PressureSwingAdsorption

SRF–ShortRotationForestry

OPR–OpenPondsRace

PBR–PhotoBioReactor

RER–European

RoW–Restoftheworld

vkm–vehicle*kilometer

MJ–MegaJoule

LHV–LowHeatingValue

7

8

1. Introduction

Theglobaldemandforfossil-basedenergysources(e.g.crudeoil,naturalgas,coal)is

growingduetoanincreasingpopulationaswellasagrowingneedforenergytofurther

industrializationandmobility(Surendra,Takara,Hashimoto,&Khanal,2014).

Yet,thisdemandisprogressivelydepletingexistingfossilsourcesandcontributingtothe

risingconcernaboutglobalwarming,ascombustingfossilfuelsincreasesemissionsof

greenhousegases(GHGs)thatwarmtheatmosphere(EC,2006).Since1990to2013the

increaseinCO2emissionsinthetransportsectorhasbeenofthe68%(IEA,2015).According

toEPA95%ofglobaltransportsreliesonpetroleum-basedfuelslikegasolineanddiesel

(EPA,2016).Therefore,tosatisfydemandformoreenergy,increasedeffortshavebeen

madetofindalternativestofossil-basedsources.Biomassisonesuchalternativeamong

manyrenewablesenergies.

InSwitzerland,thetransportsectorhasthelargestenergydemandofallsectors,largereven

thanthehouseholdsandindustrysectors(IEA,2012).In2010theCO2emissionsattributable

tothetransportsectorwere44Mt,andsince2000theSwissgovernmenthasintroduceda

lawforthereductionoftheCO2emitted,theCO2act.Thislawattemptstoreducethe

emissionsstartingfromavoluntarybasis,butifthesevoluntarymeasuresreveal

insufficient,ataxontheCO2emissionswilltakeplace.In2005anotherinitiative,coming

fromtheprivatesector,istheClimateCentinitiativethatalsoattemptsaswelltoreduce

theCO2emissionscomingfromthetransportsector,byintroducingasurchargeofCHF

0.015perliterongasolineanddiesel.Thissurchargewillhelpfinancingthereductionofthe

CO2emissions,inordertoavoidtheintroductionoftheCO2taxontransportfuels.Butfrom

2013thisinitiativehasbeen“replacedbyalegalobligationonoilimporterstooffsetdirectly

apartoftheCO2emissionsfromtransportfueluse”(IEA,2012).Lastlysince2012the

emissionslimitsofthenewcarfleetweresetequaltothoseappliedbytheEUregulation

(130gCO2/km)(IEA,2012).

Knowingallofthisitispossibletoassesshowthecurrentsituationisnotanymore

sustainable,especiallyfromtheenvironmentalpointofview,butalsofromthepointof

viewofthehumanhealth.RecentlyintheCOP21(ConferenceofParties21,2016)ithas

beendeclaredthatiftheemissionstrendcontinuesinthisway,itwouldbeeasiertogetto

thepointofnoreturnofthe2°Cincreaseofglobaltemperature.Sonowmorethaneveritis

worldwideknownthatsomemeasuresmustbeundertaken.

Biofuelshavethepotentialtoplayalargerolegloballyastheyhavetheexcellentadvantage

asdrop-infuelstodirectlyorevenpartiallysubstituteintheexistingfossilfuels,forexample

inthetransportsector(EC,2006)whereinfrastructuresandvehiclesaredurableinthe

economy,easingtheinfrastructureconcerns.AlthoughononehandbiofuelswillemitCO2

thatiscarbonneutralwhenburnedinengines,ontheotherhandwhentheyareburned

9

theywillstill,likefossilfuels,emitotherhazardouscompounds,likeNOx,NMVOC,HC,so

healthconcernsaboutthisfuelsarestillpresent,andmustbeconsidered.

Startingfrombiomassthereisthusthepossibilitytoconvertittobiofuelsdifferentfromthe

mostusedones(i.e.gasoline,diesel,methane),wearetalkingaboutelectricityand

hydrogen,which“canoffertheopportunityto“de-carbonise”thetransportenergysystem”

(KahnRibeiro&Zhou,2007)havingtheadvantageofabettertank-to-wheelefficiency,and

mostofalltheyhavenodirectexhaustemissionsatthetailpipe.Unfortunatelythecarbon

reductionassociatedtotheseenergycarriersisstrictlyrelatedonhowthehydrogenand

electricityaremade,sothattheinfrastructuresandpathwaysmightbemorecomplex(Kahn

Ribeiro&Zhou,2007).

Moreover,thebiofuelsproductionisusuallyenergyintensive,becausemanyoperations

needstobeaccomplisheduntilthefinalproductisfinished,andinsomecasesthegrowthof

thebiomassmustbeenhancedbytheuseoffertilizers,whichareenergyintensiveaswell

andwhichmaycausefurtherenvironmentalproblemsthroughtheirproduction(e.g.water

eutrophication).

Thechoicethatneedstobemadeisnotasimpleone,asitisnoteasytoanswertothe

question:whicharethebestfuelsfortransportation?

Thatiswhyatoolineasingthisdecisionmustbeadopted,liketheLifeCycleAssessment

(LCA),whichmayhelpinanalyzingtheenvironmentalburdenofthedifferentfuelsandthe

pathwaysinvestigatedforproducingthem,providingastandardizedmethodology.

InSwitzerland,aswillbeexplainedinmoredetaillater,amongtheavailablebiomass

feedstocktheonesreallyexploitablearewoodandmanurebiomass.Thisfeedstockcanbe

usedforproducingbiofuelsinmanydifferentwaysbutbothofthemmighthaveanoptimal

waytobeusedastransportbiofuels.

However,inordertoexploitthepotentialofbiomass,itisnecessarytoresolvethefood

versusfueldebate;thatis,biomassisanediblecropaswellasafeedstockforfuel

production.Accordingtothe(IEA,2008)thesearethedefinitionsforfirst,secondandthird

generationbiofuels:

•First-generationbiofuelsarethosecomingdirectlyfromagriculturalcrops,thustheyarein

directcompetitionwiththefoodproductionsector;

•Second-generationbiofuelsarethosethathaveanon-fossilorigin,andtheycancome

fromtheforestryorindustrialsector,asmainproductsorasresidues,butinanycase,they

arenon-foodfeedstock.Inthisoptic,alsomunicipalwastecanbeseenasasecond-

generationbiofuelsource;

•Third-generationbiofuelsarethosethatdonotcomefromanyagriculturalorforestall

feedstock,butarethosethatcanbecultivatedintowaterfields,likeopenponds(i.e.algae);

10

Theproductionofcurrentsocalled“firstgeneration”biofuelsrequiresintensive

agriculturalpracticeandlargelandareas(Iribarren,Peters,&Dufour,2012),which

competeswiththelanddedicatedtogrowingfoodcrops.Inordertogeneratebiofuels

sustainablywithoutthreateningfoodsupplies,theavailabilityof“second(orthird)

generation”biofuels–biomassgrowninareasnotsuitablefortraditionalfoodcrops(e.g.

algaeponds),willplayacrucialroleforafuturesustainablebiofuelproduction.Furthermore

theSwissgovernmenthasmodifiedonthe21/03/2014the“MineralOilLaw”specifyingthat

nofinancialsupportwillbegiventothosebiofuelsthatcomefromcropsfeedstock(Federal

DepartmentoftheEnvironment,2016).

1.1 SwissSituationInthepreviouschapter,ithasbeendeterminedwhybiofuelscanbeavalidreplacementas

aprimaryenergysourcefortransportation,whileinthischaptertheSwissenergyand

transportsituationwillbedescribed.

AccordingtotheTransportResearchProgrammeoftheSwissFederalOfficeofEnergy

(FederalDepartmentoftheEnvironment),itispossibletosee,asstatedabove,howthe

transportsectoristhecountry’smajorenergyconsumerwithits36.4%oftheenergy

consumption.

Figure1:Energyconsumptionperenergysector

11

Regardingtheenergysectorinstead,aftertheSwissFederalCouncilandParliament’s

decisiontophasenuclearpoweroutofSwitzerland’senergymixgoesintoeffect,theSwiss

energysystemwillberestructuredaccordingtothelong-termenergyvisionplan“Energy

Strategy2050”.Thenewenergystrategyisambitiouscallingforreductioninenergy

demandthroughefficiencymeasureswhileretainingcurrentCO2targets,displacinglarge

sharesofconventionalfossilenergy,andexpandingtheuseofrenewablesformsofenergy

(E4tech).

TheEnergyStrategy2050planisbasedonthe“EnergyPerspectives”documentformulated

bythePrognosAGcompany(Prognos,2012),inwhichhavebeenlaidoutdifferentscenarios

outto2050:

-the“BAU”(BusinessAsUsual)scenarioinwhichcurrentpoliciesshallremaininplaceand

improvementswillremainattheirhistoricalrates;

-the“POM”(PoliticalMeasures)scenario,wherecurrentpolicymeasuresareimplemented

effectively,leadingtoareductionofthefinalenergydemandofthe33%(from841PJto565

PJ);

-the“NEP”(NewEnergyPolicy)scenario,wherethefinalenergydemanddecreaseseven

further,dropping46%(from841PJto451PJ)ofthefinalenergydemand.Inthisscenario

theannualreductionofGHGsareexpectedtobe1-1,5tpercapita.

Toachievethegoalsofthelong-termenergyplan,bio-energywillplayaveryimportantrole

inboththePOMandNEPscenarios.Inordertohelpintheshifttothisnewenergysystem,

theSwissgovernmenthascreatedsevenSwissCompetenceCentersinEnergy(E4tech).

ThisthesisasapartoftheSCCERMobility,assesseswhichisthebestenvironmentalwayto

usetheavailablebiomasswithintheSwissterritoryforconvertingitinbiofuels,whichthen

willbeusedforpoweringdifferentmid-sizedvehicles.TheSCCERMobilityproject“aimsat

developingtheknowledgeandtechnologiesessentialforthetransitionofthecurrentfossil

fuelbasedtransportationsystemtoasustainableone,featuringminimalCO2outputand

PrimaryEnergyDemandaswellasvirtuallyzero-pollutantemissions”(SCCER-Mobility).The

SCCERMobilityareparallelresearchcompetencecenterswiththeSCCERBIOSWEET

(BIOmassforSwissEnErgyfuture)thatis“aconsortiumof15partnersfrom9academic

institutionsandmorethan30cooperatingpartnersfromprivateorpublicsector

organizations”,whichiscoordinatedbyPSI(PaulScherrerInstitut)(BIOSWEET,2016).SCCER

BIOSWEET“focusesontheengineeringandimplementationofbiochemicaland

thermochemicalbiomassconversionprocesseswithahighleveloftechnologicalreadiness

andsustainability”(BIOSWEET,2016)andwiththevisioninmindtoincreasetheroleofbio-

energytotheSwissenergysystemitistargetedthatanextra100PJcancomefromthese

kindofsources:33PJfromwoodybiomass,33PJfrombio-wastesandmanureand33PJ

fromalgae(Prognos,2012).

ApaperwherethesustainablebiomasspotentialinSwitzerlandisassessedistheone

writtenby(Steubing,Zah,Waeger,&Ludwig,2010).Inthisstudyismadeadifference

12

betweenthetechnicalbiomasspotentialandthesustainableone.Thefirstismerelyallthe

biomassthatistechnicallyavailableinSwitzerlandinoneyear,whilethesecondisallthe

biomassthatissustainablyavailable,where‘sustainably’meansthatotherconstraintsapart

fromtechnicalones,namelyeconomic,social,politicalandenvironmentalones.Thena

furtherdistinctionismadebetweenthesustainablebiomass,andthealreadyusedoneand

thestillavailableonearethusconsidered.

Belowasummarytableispresented:

BiomassResource SustainablePotential[PJ]

UsedPotential[PJ]

RemainingPotential[PJ]

AnimalManure 21.4 0.2 21.3

ForestWood 23.7 15.7 8

WoodfromLandscapemaintenance

6.6 3 3.6

Wastewood 7.4 3.8 3.6

FoodIndustryWaste 2.6 2.3 0.3

Biowaste 5.6 3.2 2.4

Total 67.3 28.2 39.2

Table1:Swissbiomassenergypotential

Anotherworkhasbeenrecentlydoneandwillbepublishednextyear,realizedby(Thees,

2017),thatassessestheSwissbiomasspotential.Itwashoweverpossibletogetfromthe

authorsthedataonwhichtheyarestillworking,andsofar,itispossibletoseethattheir

countingdoesnotdiffersubstantiallyfromthosemadebySteubingetal.inhisstudy.

Asummarytableisthendisplayed:

Table2:Swissbiomasspotential

0

5

10

15

20

25

30

Wood Manure IndustryWaste Biowaste

Remainingpoten

tial[PJ]

Steubingetal.(2010) Theesaeal.(2017)

13

Accordingtothesestatementswearegoingtoconsiderallsourcesthathaveanon-zero

remainingpotential.AsitispossibletoseefromTable2woodandmanurearethesources

takenintoaccountbecausetheyarethemostpromising.

Nevertheless,thealgaecultivationandexploitingforbiofuelsproductionisconsidered,

eveniftheirproductionisnotpossibleinSwitzerlandduetothenon-optimalweatherand

latitudeconditions.Althoughisreasonabletothinkthatifthistechnologyreachesits

technologicalmaturity,anabroadproductioncanbepossible,andthustheimportofthe

biofuelssoproducedcanbeanicewaytohelpinthetransitiontoacleanerandsustainable

mobilitysystem.

1.2 ResearchGoalsThemostimportantgoalofthisthesisistoassesstheenvironmentalimpactsofproducing

biofuelsfromwood,manureandalgaefortransportationandwhichcouldbethefuture

improvementsrelatedtoit.

TodothataLifeCycleAssessment(LCA)wasperformedintwoparts.Thefirstpartassesses

theenvironmentalburdenofthebiofuelsproduction,andthesecondoneinvestigatesthe

actualuseofbiofuelsindifferentmid-sizedvehicles.

Thetypeoffuelsproducedaregasoline,diesel,methane,electricityandhydrogen.Allof

themhavebeenproducedstartingfromaspecificbiomasssource.

AfurtherexplanationonhowthetwopartsoftheLCAhavebeencarriedonisthefollowing:

1. Well-To-Tank(WTT)analysisofabiomassbasedfuelpathwayincludingallstepsthat

areinbetweenthebiomasscollectionthroughprocessingtofinishedfuel,thatis

readytobefedtoacarorcanbeblendedtoconventionalfossilfuels(thisdepends

onthetypeofcarused).

2. Tank-To-Wheel(TTW)analysisincludingthecombustionofthefuelsmodeledinto

internalcombustionenginevehicles(ICEV),ortheusageoftheelectricityproducedintothebatteryelectricvehicles(BEV),andofthehydrogenintothefuelcellelectricvehicles(FCEV).WTTandTTWanalysisarecombinedtoprovideatotalWell-to-Wheel

(WTW)analysis.TheresultsoftheWTWanalysisexaminethefullenvironmental

impactsofthesefuelsandwiththeavailabilityofthedataofdifferentmediumsize

carsfromtheTHELMAProject,itispossibletoassessalsotheburdenofthesefuels

producedwhenburnedorusedindifferenttransportationunits.Inotherwordsthis

thesiswillcompleteafullCradle-to-GraveLCAanalysisoftransportation

technologiespoweredbydifferentbioenergiessourcesthatcanalsohelptoinform

futurepolicydecisions.

14

UsingthesameWTWanalysismethod,twoscenariosareanalyzed:

-A“CurrentorBaselineScenario”wheretheexistingtechnologiesareevaluatedwiththepresent-daydatainputs.Theseinputshavebeengatheredfromtheavailableliterature

whennotpresentintotheEcoinventdatabasev3.1.Thiswillhelpinconsideringwherethe

weaknessesinthesetechnologiesare,andwhichactionsshouldbepursuedinthefutureto

makethemmoreefficientandenvironmentallycompetitive.

-An“OptimizedScenario”wherethepreviousesprocessesconsideredareupdatedtoanimprovedsituation,consideringanincreaseinpotentialefficiencies,theremovalof

leakages,andcleanerprocessesthatmayallowreductioninemissions.

ThethesisistobeperformedwithintheTechnologyAssessmentgroupintheLaboratoryfor

EnergySystemsAnalysisandthePaulScherrerInstitute(PSI)inVilligen,Switzerland.Itis

partoftheTHELMAprojectwheregoodLCAsofdifferenttransportunitsarealready

availableandwillbeahelptoassesshowthebiofuelsinvestigatedinthisworkwillbehave,

asintheTHELMAprojectthereisalackofdataconcerningcarsranwithbiofuels.

15

2. LiteratureReview

Thissectionhasbeenconceivedasameansofhelpingthereadertobetterrealizethe

currentstatusoftheliteratureonthetopicoftheLCAofdifferentbiofuelsandtheir

possibleupdates,sothattheirunderstandingofthefollowingchaptermightbeeasier.

Thepaperschosenarethoseconsideredtobethemostimportantinordertorealizethis

researchwhosegoalistocomparedifferentwaystoproducebiofuelsusingtheavailable

biomassintheSwissterritory.

Somedistinctionsshouldbemadetocategorizethepapersread:

1. Reviewpaperstobetterunderstandthestateofartforthecurrentbiofuelsproduction

andtheavailablebiomassinSwitzerland;

2. PaperswheretheLCIisavailableandadaptableforthegoaltocomparedifferentfuels’

production;

Notallofthepapersreadaregoingtobehereexposed,butisimportanttosaythatagreat

efforthasbeenmadeincollectingandreviewingtheminordertoachieveagoodresultin

theresearchworkandintheLCA,sothatthecorrectinputsarechosen,andinorderto

maketheassumptionsintheOptimizedScenariostrongenough.

2.1 LiteratureontheSwisssituation“BioenergyinSwitzerland:Assessingthedomesticsustainablebiomasspotential”(Steubingetal.,2010)

InthisstudytheauthorshaveanalyzedthecurrentsituationinSwitzerlandrelatedtothe

availablebiomasspotential.Twokindsofbiomasspotentialhavebeenassessed:the

technicalandthesustainableone.Thefirstischaracterizedbythebiomasshypothetically

andtechnicallyavailableinSwitzerlandconsideringoneyear.Thesecondinsteadisunder

certainsustainableconstraintsliketheeconomic,political,environmentalandsocialones.

Afterthissubdivision,othertwocategorizationshavebeenaccounted,inordertoconsider

thebiomassenergeticallyalreadyused,andtheonethatisnotyetexploited.

Theconclusionofthisworkhasbeensummarizedintable1insub-chapter1.1.

“LifeCycleInventoriesofBioenergy-ecoinventreportNo.17”(N.Jungbluth,2007)

Inthiswork,differentpathwaysforproducingfuelsforpoweringtransportdevicesare

explored,becauseofthedepletionoffossilfuelsandtheenvironmentalimpactduetotheir

consumption.Inordertodothatbiofuels,representaviablesolutionbecausetheyare

renewableandcandirectlysubstitutefossilfuels.

16

Themaingoalofthestudyof(N.Jungbluth,2007)istoupdatetheecoinventdatabasev1.2

gatheringlifecycleinventory(LCI)dataregardingtheproductionofenergyproductsfrom

biomass.Inecoinventv1.2thedataalreadyavailablearerelatedtothefollowingproducts:

• Forestry

• AgriculturalproductsfromSwitzerland

• Woodfuels

• UseofwoodforheatingandCHP

Thereportcanbedividedinthreephases.Thefirstonewheredifferentbiofuels(e.g.

ethanol,biogas)areproducedandusedconsideringalsotheagriculturalproductsneeded

fortheconversionprocess.Theusageoftheseinvestigatedbiofuelsindifferent

transportationunitsisalsoexamined.

ThesecondphasestudiesinsteadtheimportedbiofuelsinSwitzerland.Thiswayananalysis

onthebiomassproductionandsubsequentconversionhasbeenperformedconsidering

differentcountries.Onceagaintheuseofthesebiofuelsintransportdeviceshasbeen

considered.

Inthelastphaseaparticularfocuswassetonmodernbiogasplantwithcoveronthe

storage,thathelpsinreducingthemethaneemission.

Regardingthisecoinventreport,particularemphasishasbeenputintwochaptersofit.The

firstischapter13“UseandUpgradingofBiogas”(Spiellmann,2005)wherebiogas

purificationprocess,andcombustionincogenerationenginesareexplored,andLCIsof

themareproduced.Onlythepurificationprocessofthebiogashasbeenconsideredforthis

thesis.

Thesecondoneusedischapter18“Syntheticbiofuels”(A.Dauriat,2006).Lifecycle

inventoriesofsyntheticbiofuelsareinitexplored.Mostlythefocusissetontheupgrading

ofthesyntheticnaturalgas(SNG)producedfromthegasificationofwoodbiomass.Thetwo

pathwaysexploredarerespectivelytheproductionofmethanolandmethanestartingfrom

thesyngas.Theonlypathwayconsideredinthisthesisistheonerelatedtotheproduction

ofmethane.

“Harmonizationandextensionofthebioenergyinventoryassessment-endreport”(MireilleFaistEmmenegger,2012)

Thisstudyhasbeendonewiththepurposeofupgradingandextendtheecoinvent

inventoriesof2007byEMPAthatistheSwissFederalLaboratoriesforMaterialsScienceand

Technology.

Comparedtothisthesismanypathwaysandbiofuelshavebeenexplored,considering

differentcropsandconversionprocesses,andanunconventionalwayofproducingfossil

fuel(i.e.syntheticcrudeoilfromCanadianOilSands).

Thereportcanbedividedinthreeparts.Inthefirstonethemainfocusistowardthe

17

biomassproductionandagriculturalprocessesinventories.Regardingthatanewwayon

countingnitrogenemissionswasadopted.Furthermore,forcountingtheemissionsrelated

tothelandusechangeaunifiedmethodhasbeendeveloped,asintheecoinventdatabase

theseemissionsareassociatedonlytothecuttingofrainforest.Finally,newinventoriesof

Jatrophaandothergrassmixtureswerecreated.

Inthesecondpartthefocusisshiftedtothedevelopmentoftheinventoriesofthe

conversionstepsfromtherawbiomasstillthefinishedfuel,thatarenotincludedinthe

ecoinventdatabase,ortheupdateofthepresentones.TheHTGpathway,theBCM

(Biomass-CO2-Methane)purificationprocess,theincinerationoftheMSW(MunicipalSolid

Waste)andtheextractionoftheoilcontainedinthesandsfromCanadahavebeentakenin

account.

Inthefinalpartanupdateoftheworkof(R.Zah,2007)withthenewcropsandprocesses

investigatedhasbeenperformed.

ThispaperconsidersboththebiofuelsthatareproduciblefromcropsinSwitzerlandand

fromoutsideofthecountry,withouttakingintoaccountifthereisarealpossibilityofdoing

that,thiscanbeconsideredasaweaknessofthestudy.

Attheendofthereporttheauthorsshowhowthebiofuelsinvestigateddonotperform

muchbetterthanthefossilreferenceexceptfortheGlobalWarmingPotentialandthe

OzoneDepletionPotentialcategories.

2.2 Papersdirectlyusedformodelingtheprocesses“Lifecycleassessmentoftransportationfuelsfrombiomasspyrolysis”(Iribarrenetal.,2012)

InthispapertheLCAoftheproductionofdieselandgasolinefuels,throughthefast

pyrolysisprocessofpoplarwoodfromshortrotationforestry(SRF),hasbeenconducted.

Thesystemusedtoprocessthewoodchipsobtainedfromthepoplarwoodisacirculating

fluidizedbedreactor(becauseithasbeenconsideredastheoptimaltechnologysolutionfor

thisprocess),wheremainlyabio-oilamongothergaseousorsolidsubstancesisproduced.

Thisbio-oilextractedisthenupgradedthroughahydrotreatingandahydrocrackingprocess

inordertogetthefinishedfuelsindifferentproportions,respectively43%ofgasolineand

57%ofdiesel.

ManyindicatorswereanalyzedfortheLCAconducted,thatgoesfromcradletogate,

meaningthatnoconsiderationsaredoneregardingthefuelusageinavehicle.Inthisway,

theGWPemissionsareconsiderednegative,becausethepoplarwoodisconsideredasCO2

sink.Amassandeconomicallocationofthefuelsproducedisperformedwithinthestudy.

RespecttothisworkthedatausedinthethesishavebeenadaptedtotheSwisscontest,

forestwoodwastehasbeenusedinsteadofthepoplarone(whichrequiresalsotheusage

offertilizerstogrow)andfurthermoretheactualusageofthefuelproducedhasbeen

18

consideredforpoweringacarcoveringonevehiclekilometer(vkm).Inordertomakethis

kindofanalysismorecompleteandcomparablewithotherstudiesonthesametopic,we

suggestthatadifferentapproachliketheonecarriedoutinthisthesisshouldbedone,to

makeeasierthecomparisonamongthedataobtained,whencomparingtransportfuels.

“HydrothermalGasificationofWasteBiomass:ProcessDesignandLifeCycleAssessment”(Luterbacheretal.,2009)

Inthispaperthehydrothermalgasification(HTG)ofwastebiomass(i.e.manure,waste

wood)hasbeenmodeled.Thisisapromisingprocess,becauseusesthewaterforprocessing

thebiomassinitscriticalconditions–temperatureandpressureabovethecriticalpoint–

andinthisway,itpermitstosavetheenergyusuallyneededinthepretreatmentstageof

therawbiomassfordryingit.Threescenariosareconsideredinthepaperof(Luterbacheret

al.,2009):

• Large-scaleplantforprocessingmanurefeedstock(155MWSNG)

• Small-scaleplantforprocessingmanurefeedstock(5.2MWSNG)

• Medium-scaleplantforprocessingwoodbiomass(35.6MWSNG)

Onlythefirstandthelastonehavebeenusedinthisthesis.Thefirstonebecauseofthe

largermanurebiomasspotentialinSwitzerlandcomparedtothewoodone,asstatedin

sub-chapter1.1.Thesyntheticnaturalgas(SNG)producedattheendoftheprocessis

composedforits95%withCH4andforits4%ofCO2,sototallysimilartothenaturalgasin

thegrid.

Consideringthemanurebiomassfeedstockanassumptionmadeinthispaperisthatthe

quantityofmanurenotspreadonthesoilmustbereplacedwithamineralfertilizerthatis

evenmoreefficientthanthemanureitself,andalsonotspreadingthemanureisconsidered

anavoidedprocess.DespitetheseassumptionsinthepaperofLuterbacheretal.aremade,

theyhavenotbeenconsideredforthisthesis,becauseinalltheotherprocessesconsidered

usingmanureasinputtheseassumptionsarenevercontemplated.

Intheprocessisassumedthatpartoftheheatandoftheelectricityareproducedinthe

plantitselfthroughaCHPplant.Foragoodexploitationoftheheatproducedapinchpoint

analysishasbeenperformed.MeanwhileaLCAhasbeenconductedtocalculatethe

environmentalburdenoftheproductionofthistypeoffuel.Themethodsusedfor

calculatingtheenvironmentalimpactsaretheGWPindicator,theEcoindicatorandthe

Ecoscarcitymethods.Theallocationmethodinsteadusedistheonethatconsidersthe

avoidedproductionofpartofthemineralfertilizerneededandoftheelectricityproducedin

excessrespecttothenecessityoftheplant,thatisthendistributedtothegrid.

Alloftheprocessesconsideredhavebeenmodeledintheory,becausethereisalackof

availabledataforsuchaplant.

19

ConsideringtheGWPindicatortheresultsobtainedbythispaperaredifferentrespectto

thoseobtainedbythisthesis,becausearealwaysnegativeanddonotconsidertheactual

useofthefuelproducedforpoweringavehicle.Thisisaweaknessofthispaperbecausein

thiswaythecomparisonwithotherfuelsmodeledforpoweringavehicleisnoteasyto

make.

“Algaebiodiesellifecycleassessmentusingcurrentcommercialdata”(Passelletal.,2013)

Thisdocumenthasbeenusedwithinthisthesisbecauseoftheavailabilityofthelifecycle

inventoryinit.ThestudyfromPasselletal.dealswiththeproductionofbiodieselstarting

fromthecultivationofmicroalgaeandthesubsequentextractionoftheoilcontainedinit,

usingwhichareconsideredtobethecurrentcommercialdata.

Twoscenariosarehypothesizedinit,acurrentscenario,liketheonethathasbeenassumed

inthisthesisandanoptimizedone.Inthefirstscenario,allthecurrentdatatakenfroman

existingfacilityoperatinginIsraelhavebeentaken.Thesizeofthecurrentfacility

consideredis1000m2.Thealgaestrainsusedare:Nannochlorissp.andNannochloropsissp.

withabiomassproductivityof3g/m2/day

andanoilyield

of0.24kgoil/kgdryalgae.The

sourceofCO2neededforthegrowingofthealgaearethefluegasofapowerplantco-

locatedtothefacility.Theothernutrientsneededareinsteadsuppliedusingmineral

fertilizersasasourceofphosphorousPandnitrogenN.

Thealgaecultivatedarethenharvestedanddewateredtilltheobtainmentofasolutionof

20%solid.Afterthedewateringstepawetextractionmethodisusedforextractingtheoil

containedinthealgae,usingachemicalsolventfortherecoveryoftheoilextracted.The

solventusedisthenretrieved.

Amongthebio-oilextractedfromthealgaetwootherco-productsareavailableattheend

oftheprocess,lowvaluelipidsandtheresidualbiomass(alsoknownasoilcake).Thesetwo

co-productscanhaveagoodeconomicvalueifusedinthepharmaceutical,oralimentary

sectors,orasanimalfeed(Bealetal.,2015).Insteadofaneconomicallocationanenergy

onehasbeenperformedandthenmaintainedinthethesisbecauseconsistentwiththe

allocationmethodchosen(forfurtherexplanationhavealookatsub-chapter3.2).

Theoptimizedscenarioinsteadrepresentsthesamefacility,butscaled100timesbigger.

Thesamealgaestrainsaresupposedtoincreasetheirbiomassproductivityto25g/m2/d,

andtheiroilyieldto0.5kgoil/kgdryalgae.Furthermore,thedevicesusedfordewatering

anddryingthealgaebeforetheoilextractionareassumedtoincreasetheirefficiency

accordinglytothescalingupofthefacility.

ALCAhasbeenconductedforboththebaseandtheoptimizedscenario,consideringthe

followingindicators:GWP,PhotochemicalOzoneFormation,ParticulateMatter,Water

Depletion,NER(NetEnergyRatio),NOxandSOx.Fromtheresultsobtainedintheanalysisis

possibletoshowhowusingthecurrenttechnology,andasmall-scalefacility,isnearly

20

impossibletoproduceabiofuelstartingfromthisfeedstock,becauseofthehuge

environmentalburden.Themainproblemistheenergydemandrequiredforcultivatingand

processingthealgaeismassive,nottomentionthefactthatstrongerandmoreproductive

algaestrainsmustbediscoveredorcreated.

AlreadyintheoptimizedcaseofthisdocumentthekgofCO2eq.emittedperMJoffuel

combustedinavehiclearedrasticallyreduced.

ThisdocumentandtheLCAassessmentconductedinitareofgreatinterest,becausethey

pointouthowdevelopmentsinthecultivationandharvestingstepsarestronglyneeded.

However,oneweaknessofthisdocumentanalyzedisthatnoinventoriesforthestructure

requiredforthefacilityareimplemented.Thatiswhythestructureofsuchafacilityhas

beenimplementedinthethesis.Anotherlimitationisthenrepresentedbynothaving

includedintheworktheusageofthefuelproducedforpoweringavehicle,inthiswaya

comparisonamongdifferentfuelswouldhavebeenmuchsimpler.

“Algalbiofuelproductionforfuelsandfeedina100-hafacility:Acomprehensivetechno-economicanalysisandlifecycleassessment”(Bealetal.,2015)

Thisisthelastpaperusedinthisthesisformodelingtheproductionofbiofuelsstartingfrom

algae.Thisdocumenthasbeenconsideredbecauseitincludesinitanalreadywell

optimizedmodelofapossiblelarge-scalefacilityforcultivatingandprocessalgae.The

facilityincludedis100halarge,alsointhiscasethesourceofcarbonforthealgae’sgrowth

issuppliedbyaCO2wastestreamco-locatedtotheplantandinmanyofthescenarios

analyzedthefertilizersusedasnutrientsarereutilized.Thefunctionalunitchoseis1hato

allowthecomparisonwithconventionalcropsandco-productsoftheprocessesarenot

allocatedofanyenvironmentalburden.

Manyscenarioshavebeencarriedoutinthiswork(i.e.10)andtwoalgaestrainshavebeen

used,Desmodemussp.andStaurosirasp.Thefirstoneisusedforconsideringabasecase,wherethecurrentbutinefficientprocessesforharvestingandprocessingthealgaeinorder

toextracttheoilcontainedinthem.Alltheotherscenariosinvestigatedusetheotherstrain

andconsiderdifferentwaysforprocessingthealgaeproduced.Intheendtwotargetcases

areoutlinedbytheauthors,andthesetargetcaseshavebeenusedasouroptimizedcases.

Theseoptimizedcasesarethemostpromising,consideralessusageofenergy,the

electricityusedcomefromarenewablesource,andtheprocessesforextractingtheoil

contentarethehydrothermalliquefaction,inordertousethewaterinitscriticalconditions

whereitbehavesasasolvent,andawetextractionprocessnamedOpenalgaethatuses

electromagneticforcesforsplittingupalgae’scellsandallowaneasierrecoveryoftheoil

extracted.

Inthedocumentanenergetic,economicandenvironmentalanalysisarecarriedout.Evenof

theenergeticandenvironmentalanalysisshowgreatresultsinmostofthecasesanalyzed

theeconomiconeshowshowcurrentlyalarge-scaleplantasthisoneisnotrightnow

feasibleifnotwithsomefurtherimprovementsinthedesignfacilityandinreducingthe

21

costsrelatedtomakethefacilitywork.Nevertheless,thisdocumentshowshow

environmentally,therearegreatpossibilityofenhancingthecultivationofalgae.One

weaknessthoughencounteredinthisdocumentisthatthefuelproductionisnotreally

considered,butisjustmentionedasanavoidedproduct.Also,thefunctionalunitcould

havebeendifferentasmainlyfromthisbiomassthefirstobjectiveistoproducebiofuels,

andthe1haonemaybeisnotthateffective.Thisleadsasinthedifferentpapersalready

describedtoasituationwherethecomparisonamongthedifferentbiofuelsbecomesvery

difficult.

2.3 ComparisontableInthissectionatable,wherethedifferentdocumentsanalyzedwillbecompared,is

presentedbelow:

Authors LCIAmethods(MidpointsIndicator)

MethodologicalChoices

Jungbluth(1) EnvironmentalImpact

Points

UPB06:EcologicalScarcity

Eco-Indicator99

EconomicAllocationco-

products

Emmeneger(2) GWP100aIPCC2001

GWP100aIPCC2007

ILCDmidpoints

CML

Whenpossibleallocationon

physicalbasis(massor

energy)otherwiseeconomic

allocation

Iribarren(3) CML Massandeconomic

allocation

Luterbacher(4) GWP100a2007

Eco-Indicator

Eco-Scarcity

AvoidedProductsand

Emissions

Passell(5) VariousIndicators

Considered

EnergyAllocation

Beal(6) Impacts2002

ImpactsAssessment

Methods

AvoidedProductAllocation

Table3:Literaturereviewcomparison

(1)(N.Jungbluth,2007);

(2)(MireilleFaistEmmenegger,2012);

(3)(Iribarrenetal.,2012);

(4)(Luterbacheretal.,2009);

(5)(Passelletal.,2013);

(6)(Bealetal.,2015)

(1)and(2)havebeenusedhasreferencesforcomparingthisthesis,astheydealwiththe

biofuelproductionontheSwissterritoryaswell.(3)(4)(5)(6)havebeenharmonizedand

22

usedinordertoreachthegoalofthisthesis.

InthediscussionsectiontheresultsobtainedfortheGWPindicatorwillbediscussed.

3. Methodology3.1 LifeCycleAssessment(LCA)InordertoassesstheenvironmentalburdenoftheprocessesexploredinthisthesisLCAis

animportantstandardizedmethodthatquantifiestheenvironmentalimpactsofgoodsand

processesfrom“cradletograve”,thusconsideringthewholelifeofaproduct.Thiscanbea

significanttoolforbetterunderstandinghowasingleprocesscanaffecthumanhealthand

theenvironment,inthiswayisthenpossibletoidentifytheactionsthatcanbereally

undertaketoimproveandoptimizetheprocesses.

InordertoexplaintothereaderthegeneralconceptsatthebaseoftheLCAmethod,the

informationaregatheredaccordingtothedocumentof(Stoppato,2013).

ForthestandardizationofthemethodtheISO14000seriesstandardshavebeenused,as

theyareworldwidegenerallyacceptedasasharedreferencetoexecuteanLCA.

TheISO14040seriesisconstitutedoftwonorms,eachofthemdevotedtoaspecificpartof

themethodology:

• ISO14040:2006-Environmentalmanagement-Lifecyclemanagement-Principles

andFramework;

• ISO14044:2006-Environmentalmanagement-Lifecyclemanagement-

RequirementsandGuidelines;

Accordingtothe(ISO,2006)thecurrentdefinitionofLCAisthe“compilationandevaluationoftheinputs,outputs,andpotentialenvironmentalimpactsofaproductsystemthroughoutitslifecycle”andthiscanbemadeinfourdifferentsteps:

i. Scopeandgoaldefinitionii. LifeCycleInventoryanalysis,LCIiii. LifeCycleImpactAssessment,LCIAiv. Interpretation

3.2 ScopeandGoaldefinitionItisveryimportantthatbeforestartingaLCA,thegoalsandscopeoftheanalysisarewell

defined.Itmustbeveryclearatthestartofitwhatthemotivationsbehindtheanalysisare,

andwhatkindofaudiencecouldbeinterestedinitandinitsresults(Stoppato,2013).

ItisthenpossibletofixtheFunctionalUnitandtheBoundariesofthesysteminvestigated.

Thisisacentraloperation,asaccordingtoittheresultsmaychangesignificantly,andagood

23

choicecouldhelpthefinalreadertobetterunderstandwhattheworkistryingto

communicate.

Inthisthesis,theFunctionalUnitfixedforthefirstpartoftheLCAis1MJoftransportfuelin

theformofgasoline,diesel,biomethane,hydrogenorelectricity,becauseinthiswayitis

possibletocomparetheresultsobtainedwithvaluesfoundinliterature.Forthesecondpart

oftheconductedLCAthefunctionunitchoseisvkm(vehiclekilometer),asitallows

comparingdifferentmid-sizedvehiclescovering1km.Theresultsobtainedwhencomparing

thedifferentvehiclesarenotdirectlycomparablewiththeliteraturevalues,becauseofthe

largevariationoftheLCAresultsandenergyconsumptionofthecars.OtherFunctionalUnits(FUs)couldhavebeenchosen,butaswearecomparingenergy

carriers,itseemedmoreappropriatetocompareanenergyfunctionalunitforthefirstpart

andavehicleunitforthesecond.Theinterestofthisthesisresidesinexploringthedifferent

pathwaysfrombiomasstotransport,whichiswhyweusetheFUofvkm.However,inorder

tocomparewithotherbiofuelstudies,wealsocalculateresultswiththeFUofMJ.

RegardingtheboundariesoftheprocessconsideringthefirstpartoftheLCAtheyare

relatedtothefuelproduction.Inthiscasetheprocessstartsfromthecollectionoftheraw

biomassthatusuallyleadstoanintermediateproduct(e.g.biogas).Theintermediateisthen

upgradedtothefinishedfuel.Notinalltheprocessesthereisthisintermediatestep,asfor

examplewhenburningthewoodchipsinacogenerationplantforproducingelectricity.

ConsideringinsteadthesecondpartoftheLCAtheproducedfuelsareusedforpowering

differentvehicles,soforeveryprocessalsotheproduction,theusageandthedisposalof

thecarisconsidered.

3.3LifeCycleInventories(Collection)-LCIThisphaseoftheanalysisisaboutthegatheringofthedatathatconstitutetheinputand

outputflowsofthesystem.Thiswayitispossibletoquantifythestreamsofmaterialsand

energiescomingfromtheenvironment,andtheemissionintoit,togetherwiththewastes

thatareproducedbythevariousprocesses.

Thisisaverydelicatephase,astheresultsobtainedattheendofthecalculation,willbe

entirelydependentonthiskindofdata.ThatiswhytheLCApractitionershouldputalotof

effortsinit,tomakehisanalysisthemostrealisticpossible,knowinghoweverthatitisbyno

meansaneasytask(Stoppato,2013).

Inthisthesis,theecoinventdatabasev2.2and3.1havebeenusedformodellingdifferent

processesthatareavailableinit.TheecoinventdatabaseisaLifeCycleInventory(LCI)

database,andisoneofthemostextensiveones,asitincludesprocessesfordifferentareas

goingfromenergysupplytowastetreatments,andisworldwideknownasoneofthe

largestdatabase(SimaPro,2016).Whentheprocessesinvestigatedwerenotpresentinthe

24

ecoinventv2.2and3.1,LCIfromthepapersmentionedintheliteraturereviewhavebeen

usedinstead.

Furthermore,whenaprocesshasmultipleoutputsawayofdetermininghowmuchthe

processburdensareallocatedtoeachproductmustbedecided.

Mostofthetimetheallocationmethodusedistheonethatconsidersthemassofthe

differentproducts(Stoppato,2013).Inthisworkanenergyallocationmethodhasbeen

chosenwhendealingwithmultiproductsoutcome(e.g.gasolineordieselproduced

togetherfromthepyrolysisprocess)oranexergyallocationmethodwhendealingwiththe

cogenerationplants.Insteadoftheenergyallocationmethodthisonehasbeenpreferred,

asitisagoodwaytoconsidertheelectricityaformofenergymorevaluablerespecttothe

heatco-produced,forwhichaheavierenvironmentalburdenmustbeattributedtoit.

Anotherwayofconsideringtheseprocesseswasrealizedwhenmodelingoneofthealgae

pathwaysinvestigatedinthisthesis.Inthatcaseanenergyallocation,amongthedifferent

outputshasbeenperformed,inordertoconsideronlytheenvironmentalburdenassociated

withthebiofuelproduction.Nevertheless,alsoasystemexpansionoftheprocesshasbeen

considered,whichmeansthattogetherwiththebiofuelproductionthebiomassremaining

aftertheoilextractionwasconsideredasanavoidedproductionofanimalfeed.Inthisway,

thisavoidedproductrepresentacreditindifferentimpactcategories.

Anexamplewillbeshownbelow:

Fromthesameinput,whichisalgae,itispossibletoobtaintwocoproducts,whicharethe

Bio-oilextractedfromthealgaeandtheanimalfeedthatisconstitutedbytheremaining

biomass.Whenallocatingthedifferentburdens,the90%ofitcanbereferredtothebio-oil

produced,whiletheremaining10%tothecoproduct.

3.4LifeCycleImpactAssessment(LCIA)InthisphasetheenvironmentalburdencarriedbyalltheinputsandoutputsintheLCIare

evaluatedandshownindifferentimpactcategories,relatedtothehumanhealth,the

environmentandtheresourcedepletion.Inotherwords,thescopeofthisphaseisto

Algae Bio-Diesel

BioOil

Animal

Feed

90%

10%

25

quantifytheenvironmentalchangesduetohumanactivity.

Thecalculatedimpactcategoriesarestrictlyrelatedtothemethodchosen.Thisworkis

basedontheReCiPeMethodv1.08accordingto(MarkGoedkoop,2013),withthe

Hierarchical(H)perspective,whichconsideralifetimeof100years.Thismethodhasbeen

chosenabovetheothers,becauseitiswellacceptedintheLCAcommunityandisquiteup-

to-date(MarkGoedkoop,2013).

Themidpointindicatorsarethoseshowninthetablebelow:

Image1:Mid-pointIndicators-Source:(MarkGoedkoop,2013)

Themidpointindicatorsconsideredforthisthesisandashortdescriptionofthemis

thereforeshown:

• ClimateChange:waschosenforobviousreasons.ItregardstheeffectoftheGreen

HouseGases(GHGs)onthehumanhealthandontheenvironment,whichare

responsibleoftheglobalwarming.Eachcompoundconsideredinthiscategoryhas

itsownpotential,basedonthevaluegiventothembytheIntergovernmentalPanel

onClimateChange(IPCC),foundedonitscapacitytoabsorbtheradiationsandon

thepermanencetimeintheatmosphere.ForexampletheCO2hasapotential

impactvalueof1whiletheCH4hasapotentialimpactvalueof25;

• FreshwaterEutrophication:isthepotentialduetotheriseofthenutrientslevelsinto

thewaterbodies,especiallynitrogenandphosphorus(MarkA.J.Huijbregts,2014).

Thisindicatorwaschosenbecauseinsomeoftheprocessesinvestigatedthereisthe

useoffertilizers(i.e.algae)orofcatalysts;

26

• ParticulateMatterFormation:thisimpactcanaffectthehumanhealth,becausethe

smallparticlesemissionsfromthecombustionofthefossilfuels,orfromthe

interactionwiththeatmosphere,candeeplyenterintothelungsandcause

dangerousrespiratoryproblems.Thisindicatoriscommonlyusedwhendealingwith

transports;

• NaturalLandTransformation:theimpactcausedbythetransformationofthe

originalcharacteristicofaland(AbhishekChaudhary,FrancescaVerones,Laurade

Baan,StephanPfister,&Hellweg,2014).Asbiofuelsareworldwideknownforbeing

responsibleofthelandusechange,wethoughtthatisworthconsideringthisimpact

categoryaswell;

Theothermidpointswillnotbedisplayednotbecausetheyarelessimportantthantheone

considered,butbecauseforthegoalofthethesisthesemidpointindicatorsseemedtobe

moreeffective,andalsoforamatterofspacetobededicatedinthework.Neverthelessat

theendofthethesis,theresultscalculatedforalltheothersindicatorswillbeshowedfor

thosewhomaybeinterestedinit.

3.5InterpretationAtthisphasetheresultsobtainedcanfinallybeanalyzed,sothatsignificantproblems,

completeness,reliabilityandsensitivitycanbeoutlined.

AfterrunningaprocesswiththeSimaProsoftwarev8.04,itispossibletodiscernwhichare

theitemsintheprocessthatrequiremoreinvestigations,inordertoexplainwhytheyare

sobadlyaffectingtheentireprocess,orsomespecificimpactcategories.Doingthatitis

possibletogivespecificrecommendationsaboutwhichactionscanbeundertake,orwhat

canbedoneinthefuture.

AstheLCAisaniterativeprocedurebecauseofthehugedifficultiesinretrievingthedata.In

addition,oncetheresultsfromthechosendataareobtained,ispossibletoseewhich

processismoreimportant,andwhereitisnecessarytointerveneformakingsome

improvements.

Furthermore,basedonthepreliminaryresults,alsothescopeandgoalsofthestudiesmay

bechanged.

3.6 BiogenicEmissionsInthisthesis,weevaluatebiogenicCO2emissionswhenbiologicalfeedstocksareused.With

thetermbiologicalfeedstocksweincludeallthosematerialsthathaveanon-fossiloriginor

arebiodegradable(e.g.forestandagricultureproductsorwastes)(UnitedStates

EnvironmentalProtectionAgency&OfficeofAtmosphericPrograms,2014).

27

BecausethecarboninthebiomasswasoriginallytakenfromCO2intheatmosphere,it

shouldnotbecountedtocontributetoglobalwarmingwhenitisre-releasedtothe

atmosphere.ThisisbecausethesequestrationoftheCO2fromtheatmospherebytheplant

wasnotcountedinthefirstplace.

However,greatcarewastakenwhendefiningwhichemissionsfromthebiofuelpathways

werefromfossilsourcesandwhichfrombiogenicsources.

3.7Base&OptimizedScenarioConsideringthedifferentpathwaysinvestigatedaharmonizationworkhavebeen

performedforalltheassumptionsfoundoutinthedifferentpapersinordertocreatea

basecaseforeachofthem.UsuallytheFUsusedintheliteratureweredifferentforthe

oneschosenionthisstudy,thusthiswasthefirstimportantchangetobedone.The

electricitymixusedinthebasecaseisalwaysthesameandistheSwissaveragemix,taken

fromtheecoinventdatabase.Theonlyexceptionisforthebasecaseprocessesconsidering

thealgaecultivation,becauseasitwassaidearlier,Swissweatherconditionarenon-

optimalfortheircultivation(MariluzBagnoud-Velasquez,2016),inthosecasestheItalian

averagemixhasbeenused(stillfromtheecoinventdatabase).

Theheatsourceconsideredintheprocessesharmonizedfromtheliteraturereviewis

naturalgas.

Theallocationmethodusedistheenergyonewithmulti-productsprocesses,whilethe

exergyallocationonehasbeenchosenfortheprocessesproducingbothheatand

electricity.

Oneoftheaspectsofthisharmonizationwastoconsiderthefuturedevelopmentofeach

pathway.Thisisbecausesomepapersreporteddataforcurrenttechnologyperformance,

whileothersconsideredmanyfutureimprovements.Forthisreasonforeachprocessabase

caseandanoptimizedonewasquantified.However,forsomepathwaysitwasnotpossible

tofindliteraturedescribingthepotentialforfutureimprovements.Thisiswhydifferent

assumptionshavebeencarriedoutforupgradingtheprocesses,inordertoshowtothe

readerhowtheycouldbeifoptimizingsolutionswereadoptedforthem.

Withtheseassumptions,wearenottryingtosaythattheyarealwaysfeasibleforthe

differentplantsandlocations,buttheaimofthisscenarioistoshowwhatthesameprocess

wouldbeifspecificchangesweremade.

Theassumptionsthereforemadearethefollowing:

• Renewableelectricitysource:fortheprocessesconcerningthedifferentbiofuelsproductioninsteadoftheSwisselectricitymixattheconsumer,ortheelectricitymix

usedfortheproductionofalgaeindifferentcountrieswithbetterweather

conditions(e.g.Italy),ithasbeenchosentheelectricityproducedinahydropower

plant.Thisisbecauseamongthevariouswaysofproducingelectricityfrom

renewablesources,thispathwayhasbeenproventohavethesmallest

28

environmentalimpact.Inordertobeconsistentinthework,theelectricityusedin

alltheoptimizedscenariosofthedifferentprocessesisthesame.

• Leastimpactingtransportation:asintheliteraturereviewitwasfoundthatthetransportsusedhadastronginfluenceinthefinalresults;itwasconsideredthatthe

bestcurrentlyavailabletransportstobeused,insteadofthefleetaverageones.

• Emissionscut:accordingtotheDirective70/220/EECitispossibletoseehow,forthelightdutyvehicles,sincethisdirectivehasbeenapplied,theemissionscutfor

manycompoundslikeCO,NOx,HC,PM,havebeendrasticallyreducedstartingfrom

theEURO1standardstilltheEURO6standards.Basedonthisdocument,itis

reasonabletoapplythesamelinesofthoughttotheprocessthatareinvestigated

withinthethesis,andtoapplyanemissioncutofthesamekindsofcompoundsand

othershazardoustypes,giventhattheprocessitselfcanbecleanerandmore

efficient.Theemissionshavebeenthusreducedby50%,exceptwhenitcomesto

dealingwithCO2andwateremissions,astheyhavebeenconsideredasstrictly

relatedtothequantityofbiomassitselfused,soifthereisanincreaseinefficiency

thatpermitstheuseoflessbiomass,thereductionappliedwillbeofthesame

amount.

Thereductionamongtheothersubstancesisconsideredconsistentbecausetheyare

strictlyassociatedwiththeprocessitself,thatistosayconsideredmoreefficientand

cleaner.Forexample,wemayassumethatthecombustionprocesses,ifthereare

any,aremuchbetter.

Alsotheleakagesofmethaneintheanaerobicaldigestionplantshavebeenremoved

intheoptimizedcase.

• Car’sStandardUsed:thevehiclesusedforthecomparisonamongthedifferentfuels

investigatedforpoweringthemareallundertheEURO5standards.Thischoiceis

drivenbythefactthatthebestavailablecarforsimulatingtheburningofthe

biofuels,uploadedintheecoinventdatabasefromtheThelmaprojecthassuch

standards.

Thecarsusedforthecomparisonareallmid-sizedandthetypologiesconsideredare

thefollowing:

-InternalCombustionEngineVehicle(ICEV)forgasoline,dieselandnaturalgas(NG);

-BatteryElectricVehicle(BEV)forelectricity;

-Fuel-CellElectricVehicle(FCEV)forHydrogen;

• LHVofBiofuelsequaltoconventionalfossilfuels:weassumedthatlowheating

valuesofthebiofuelsinvestigatedarethesameoftheconventionalfossilfuelsused

asreference.

• Increasedefficiencyofprocesses:thisassumptionisbasedontheassumptions

madein(Weinberg&Kaltschmitt,2013).Itisconsideredthatinthenearfuturean

29

increaseoftheefficiencyofdifferentprocessesforconvertingbiomassintobiofuels

willincreasebyatleast10%.Accordingtothisassumptionareductionofthesame

amountofthequantityofbiomassneededbytheprocess.

• AlgaeOptimizedScenario:Accordingtodifferentpapers(Passelletal.,2013;Zhouetal.,2014)consideringthecurrentsituationmanyassumptionsmustbetakeninto

account,ifitisdesiredthattheproductionofbiofuelsfromalgaebecomesareal

possibility.

Afurtherexplanationoftheimprovementsmadewillbegiveninchapter6.

30

4. LCIoftheprocessesusingWoodBiomassTheprocessesthataregoingtobeinvestigatedinthischapter,consideringonlytheuseof

woodybiomassarethefollowings:

• WoodGasification&Methanation

• HydrothermalGasification(HTG)

• FastPyrolysis

• WoodGasification&Hydrogenproduction

• CogenerationHeatandPowerPlant(CHP)

Theseprocesseshavebeenchosenformanifoldreasons.Theproductionofdifferentenergy

carriers(methanevselectricityversusliquidhydrocarbons)isoneofthem.Secondly

becausetheWoodGasificationprocessfortheproductionofSNGandtheCHPplant,

becausearethosewiththehighestleveloftechnologicalmaturity,comparedtothe

HydrothermalGasificationandFastPyrolysisprocesses.Thelasttwohavenevertheless

beeninvestigatedbecausetheyrepresentpromisingtechnologiesforthenearfuture,

especiallytheHTG,eveniftheyareattheirearlystageoftheirtechnologicalmaturity.

Aflowchartassessingthedifferentpathwaysexploredispresentedbelow:

31

Flowchart1:WoodBiomassPathways

Where:

• HTG:HydrothermalGasification

• SNG:SyntheticNaturalGas

4.1 WoodGasification&MethanationProcess-LCIThisprocessreferstotheconversionofwoodchipsmix(i.e.woodchipsfromwood

industry,fromforestrywasteandfromwastedemolitionandurbanwood)intosyngas

(SNG)amixtureofmainlyH2andCO,withtracesofCO2andCH4,thatissubsequently

convertedintomethane(96%).TheLCIispresentintheecoinventdatabase,andis

documentedbytheecoinventreportof(A.Dauriat,2006).

32

Thechemicalreactionhappeningwhenconvertingthesyngasintomethaneisthefollowing:

! + #$% → !% + #$

Animagetakenfromthereportwillshowthesystemboundariesoftheprocess:

Figure2:WoodGasification&Methanationprocessboundaries-Source:(A.Dauriat,2006)

ThewoodchipsaregasifiedthroughthegasificationstageinaFICFB(FastInternally

CirculatingFluidizedBed)withanoverallefficiencyofthe73%.Thebedmaterialconsidered

ismadebyolivine,amagnesium-ironsilicatethatisthoughreplacedbytheprocesssilica

sand.ForthecleaningoftheSNGrapemethylesterisusedforthetarremoval,andother

chemicalcompoundlikesoda(NaOH)andsulphuricacidareusedtogetridofthe

impurities.

Themethanationstagewithanefficiencyofthe76.5%leadstotheproductionofagaswith

thiscompositionandenergycontent:

Compound Percentage(vol.)CH4 97.3%

CO2 2.6%

H2O 0.1%

EnergyContent 34.4MJ/Nm3

33

Table4:Gascompositionfromwoodgasification

Thecatalystusedisintheprocessisrespectively50%AluminumOxideand50%Nickel.The

carbondioxidepresentintheSNGisremovedbyapressure-swingadsorption(PSA)process,

throughazeolitesieve.

Theheatrequiredinalltheprocessisobtainedfromtheburningofsomeofthemethane

producedwith95%efficiency.

Thetransportdistanceconsideredis50km,usinga28ttruck.Theelectricityconsumedinto

theprocessisneededforthefollowingoperations:woodchipsdrying,compressionof

syngasandmethane,pumpingofthebiomassandaircompression.

Thelifetimeoftheplantisassumedtobe50years.

TheassumptionsmadefortheOptimizedScenario,carriedontoassesstheimprovements

thatcanbemadetotheverysameprocessanalyzedintheBaselineScenario,arethe

following,andarebasedonthosemadeinthe3.6chapter:

• Increaseoftheefficiencyoftheprocessby10%;

• Reductionofthedirectatmosphericemissionsoftheprocessby50%;

• TransportisprovidedbyaEuro6Lorry;

• ElectricityisassumedtocomefromHydropower.Theelectricityusedisalowvoltage

one,andtheprocessisnamed“Electricity,lowvoltage,hydropower,2030+,atgrid

CH/U”,whichwascreatedfortheThelmaproject(StefanHirschberg,2016);

Thedatasetsshownbelowconcerntheproductionof1m3ofSNGinboththeBaseandthe

Optimizedcases:

Products Base Optimized UnitMethane,96vol.-%,fromsyntheticgas,wood,atplant/CHU 1 1 MJ

Materials/fuels

Woodchips,mixed,u=120%,atforest/RERU 3,64E-04 3,64E-04*0.9 m3

Woodchips,mixed,fromindustry,u=40%,atplant/RERU 1,25E-04 1,25E-04*0.9 m3

Wastewoodchips,mixed,fromindustry,u=40%,at

plant/CHU

7,97E-05 7,97E-05*0.9 m3

Syntheticgasplant/CH/IU 8,42E-11 8,42E-11*0.9 p

Lightfueloil,burnedinboiler100kW,non-modulating/CHU 1,78E-05 1,78E-05*0.9 MJ

Electricity,mediumvoltage,atgrid/CHU 2,40E-02 2,40E-02*0.9 kWh

Tapwater,atuser/CHU 3,05E-02 3,05E-02*0.9 kg

Rapemethylester,atesterificationplant/CHU 4,24E-04 4,24E-04*0.9 kg

Aluminiumoxide,atplant/RERU 1,25E-11 1,25E-11*0.9 kg

Zinc,primary,atregionalstorage/RERU 5,42E-05 5,42E-05*0.9 kg

Nickel,99.5%,atplant/GLOU 1,25E-11 1,25E-11*0.9 kg

Charcoal,atplant/GLOU 5,74E-04 5,74E-04*0.9 kg

Silicasand,atplant/DEU 1,02E-03 1,02E-03*0.9 kg

Sodiumhydroxide,50%inH2O,productionmix,at

plant/RERU

3,53E-05 3,53E-05*0.9 kg

Sulphuricacid,liquid,atplant/RERU 2,99E-04 2,99E-04*0.9 kg

34

Transport,freight,rail/CHU 1,56E-03 1,56E-03*0.9 tkm

Transport,lorry20-28t,fleetaverage/CHU 1,20E-04 1,20E-04*0.9 tkm

Transport,lorry3.5-20t,fleetaverage/CHU 1,03E-02 1,03E-02*0.9 tkm

Electricity,lowvoltage,productionUCTE,atgrid/UCTEU 2,37E-04 2,37E-04*0.9 kWh

Industrialfurnace,naturalgas/RER/IU 5,98E-10 5,98E-10*0.9 p

Emissionstoair

Carbondioxide,biogenic 1,42E-01 1,42E-01*0.9 kg

Heat,waste 1,15E+00 1,15E+00*0.9 MJ

Acetaldehyde 2,14E-10 2,14E-10*0.9 kg

Aceticacid 3,20E-08 3,20E-08*0.9 kg

Benzene 8,54E-08 8,54E-08*0.9 kg

Benzo(a)pyrene 2,14E-12 2,14E-12*0.9 kg

Butane 1,50E-07 1,50E-07*0.9 kg

Carbonmonoxide,biogenic 9,94E-05 9,94E-05*0.9 kg

Dinitrogenmonoxide 1,07E-07 1,07E-07*0.9 kg

Dioxin,2,3,7,8Tetrachlorodibenzo-p- 6,38E-18 6,38E-18*0.9 kg

Formaldehyde 2,14E-08 2,14E-08*0.9 kg

Mercury 6,41E-12 6,41E-12*0.9 kg

Methane,biogenic 4,27E-07 4,27E-07*0.9 kg

Nitrogenoxides 6,04E-05 6,04E-05*0.9 kg

PAH,polycyclicaromatichydrocarbons 2,79E-08 2,79E-08*0.9 kg

Particulates,<2.5um 1,58E-06 1,58E-06*0.9 kg

Pentane 2,56E-07 2,56E-07*0.9 kg

Propane 4,27E-08 4,27E-08*0.9 kg

Propionicacid 4,27E-09 4,27E-09*0.9 kg

Sulfurdioxide 1,17E-07 1,17E-07*0.9 kg

Toluene 4,27E-08 4,27E-08*0.9 kg

Hydrocarbons,aliphatic,alkanes,unspecified 2,14E-06 2,14E-06*0.9 kg

Hydrocarbons,aliphatic,unsaturated 7,27E-06 7,27E-06*0.9 kg

NMVOC,non-methanevolatileorganiccompounds,

unspecifiedorigin

1,43E-06 1,43E-06*0.9 kg

Wastetotreatment

Treatment,sewage,fromresidence,towastewater

treatment,class2/CHU

3,12E-05 3,12E-05*0.9 m3

Disposal,inertmaterial,0%water,tosanitarylandfill/CHU 2,17E-03 2,17E-03*0.9 kg

Disposal,usedmineraloil,10%water,tohazardouswaste

incineration/CHU

4,24E-04 4,24E-04*0.9 kg

Disposal,woodashmixture,pure,0%water,tomunicipal

incineration/CHU

5,78E-04 5,78E-04*0.9 kg

Disposal,woodashmixture,pure,0%water,tosanitary

landfill/CHU

4,37E-04 4,37E-04 kg

Table5:MethanewoodgasificationLCI

4.2 FastPyrolysisProcess-LCIThisprocessismodelledbasedonthepaperof(Iribarrenetal.,2012).Thisprocess

analyzedconsistin“thethermaldecompositionofbiomassintheabsenceofoxygen,

producingcharcoal,non-condensablegasandaliquidrichinoxygenatedhydrocarbons,

whichisofmajorinterestforbiofuelapplications”(Iribarrenetal.,2012).Theprocess

conditionsareveryimportantinordertomodifytheyieldsofthedifferentproducts.To

maximizetheliquidyield,thatisthemostinterestingoneifwearedealingwithbiofuel

35

productionfortransportation,theprocessmustbecarriedonat500°C,atmospheric

pressure,withveryshortresidencetime(Iribarrenetal.,2012).

Figure2:FastPyrolysissystemboundaries-Source:(Iribarrenetal.,2012)

Fewmodificationshavebeenmadeinrespecttotheoriginalwork,inordertoadapttheLCI

presentinittothepurposeofthethesis.Forexampleintheoriginalworkpoplarwood

chipsfromshortrotationforestrywereusedtoperformtheanalysis,whilenowsoftwood

forestrywoodchipsfromSwitzerlandsubstitutethem;thischoicewasmadebecausethe

densitydifferenceofthistwokindofwoodspeciesisnegligible(410versus430kg/m3).Also

thefunctionalunithasbeenchanged,becauseinsteadofanalyzingtheproductionof1ton

oftheconventionaltransportationfuelsproduced(e.g.gasolineanddiesel)withthe

upgradingofthebiocrude,thatistheoilproducedwiththepyrolysisprocess,weanalyze

theproductionof1MJofgasolineand1MJofdieselrespectively.Todothat,firstlythe

originaldatafortheproductionofthebiocrudewereadaptedtotheproductionofjust1kg

ofit.Secondlyfortheupgradeofthebiocrude,andtheproductionof1MJofgasolineand

diesel,anenergyallocationmethodhasbeenused.Furthermore,insteadofusingSpanish

inputs,ortheSpanishelectricitymix,SwissinputsandtheSwisselectricitymixhavebeen

usedinstead.

Anotherdifferenceisthattheenergyrequiredforthetreatmentoftherawbiomass(e.g.

drying,commuting)isnottakenintoaccountasithasalreadybeenwiththeecoinvent

process.

Thecatalystthatwasnotclearlyshowedintothestudywasmodelledbasedonthepaperof

(Snowden-Swan,Spies,Lee,&Zhu,2016).

Thetransportationdistancesconsideredarerespectively,80kmforthecollectionofthe

woodchips,and200kmforthefinalproducts(Iribarrenetal.,2012).

Thedieselandgasolineintheoriginalworkarecoproducedwhenupgradingthebiocrude

createdfromthefastpyrolysis.Hereforabettercomprehensionofthesingularproductsan

energyallocationhasbeenperformedasshowedinTable5:

36

Product MassPercentage[%] LHV[MJ/kg] EnergyAllocationDiesel 57 42.8 0.56

Gasoline 43 44.4 0.44

Table6:Energyallocationpyrolysisproducts

TheLCIsfortheproductionof1kgofbiocrudefromthepyrolysisprocess,andforthe

productionof1MJofdieselandgasolinerespectivelyarepresentedbelow,includingthe

baseandtheoptimizedcase.

Intheoptimizedcasetheassumptionstakenintoaccountarethesameonesstatedinthe

previoussubchapter:



• TransportisprovidedbyaEuro6Lorryinsteadofthefleetaverageone;

• ElectricityisassumedtocomefromHydropowerandithasbeensubstitutedwitha

hydropowerlowvoltageelectricitydatasets,modelledwithintheThelmaproject

(StefanHirschberg,2016);

• Thebio-crudeusedintotheoptimizedcasehasbeenalsooptimizedusingthe

differentassumptionscarriedoninsub-chapter3.6,likethereductionofthe

emissionof50%,theuseofhydropowerelectricity(StefanHirschberg,2016),and

thetransportsareprovidedbyaEURO6lorry;

Products Base Optimized UnitBio-crudebasecase 1 0 kg

Bio-crudeOptimized 0 1 kg

Resources

Air 2.2238 2.2238*0.9 kg

Materials/fuels

Woodchips,wet,measuredasdrymass(CH)|softwood

forestry,mixedspecies,sustainableforest/AllocRec,U

2.3392 2.3392*0.9 kg

Water,deionised,atplant/CHU 0.0388 0.0388*0.9 kg

Transport,lorry20-28t,fleetaverage/CHS 0.187 0 tkm

Transport,freight,lorry16-32metricton,EURO6|transport,

freight,lorry16-32metricton,EURO6|AllocRec,U

0 0.000168 tkm

Electricity/heat

Electricity,lowvoltage,atgrid/CHU 0.1356 0 kWh

Electricity,lowvoltage,hydropower,2030+,atgrid/CHU 0 0.1356*0.9 kWh

Heat,naturalgas,atindustrialfurnace>100kW/RERU 0.000683 0.000683*0.9 MJ

Wastetotreatment

Woodashmixture,pure(wastetreatment)|treatmentof,

landfarming|AllocDef,U

0.0135 0.0135*0.9 kg

Table7:BiocrudefromwoodfastpyrolysisLCI

37

Products Base Optimized Unit CommentsGasoline 1 1 MJ

Materials/fuels


Naturalgas,lowpressure,atconsumer/CHU 0.01315 0.01315*0.9 MJ


Transport,freight,lorry16-32metricton,

EURO6|transport,freight,lorry16-32metric

ton,EURO6|AllocRec,U

0 0.00459 tkm Transportof

thefinished

fuel

Bio-crudeoilBaseCase 0.116 0 kg

Bio-crudeoilOptimized 0 0.116 kg

MoS2/NiSonAl2O3 0.00008 0.00008*0.9 kg Catalyst

Electricity/heat

Electricity,lowvoltage,atgrid/CHU 0.00172 0 kWh Hydrotreating

Electricity,lowvoltage,hydropower,2030+,at

grid/CHU

0 0.00172*0.9 kWh

Electricity,lowvoltage,atgrid/CHU 0.00241 0 kWh Hydrocracking


grid/CHU

0 0.00241*0.9 kWh

Electricity,lowvoltage,atgrid/CHU 0.00275 0 kWh Steam

Reforming(SR)


grid/CHU

0 0.00275*0.9 kWh

Emissionstoair

Water_kg 0.02188 0.02188*0.9 kg FromSR

Carbondioxide 0.05967 0.05967*0.9 kg FromSR

Emissionstowater

Water_kg 0.01472 0.01472*0.9 kg

Wastetotreatment

Wastewater,averagetreatmentof,capacity

1.6E8l/year|AllocDef,U

0.05519 0.05519*0.9 l

Table8:GasolinefromwoodfastpyrolysisLCI

Products Base Optimized Unit Comments

Diesel 1 1 MJ

Materials/fuels


Naturalgas,lowpressure,atconsumer/CHU 0.0107 0.0107*0.9 MJ



EURO6|AllocRec,U

0 0.0189 tkm Transportof

thefinished

fuel

Bio-crudeoilBaseCase 0.094 0 kg

Bio-crudeoilOptimized 0 0.094 kg

MoS2/NiSonAl2O3 0.000063 0.000063*0.9 kg Catalyst

Electricity/heat

Electricity,lowvoltage,atgrid/CHU 0.001404 0 kWh Hydrotreating


grid/CHU

0 0.001404*0.9 kWh

38

Electricity,lowvoltage,atgrid/CHU 0.001966 0 kWh Hydrocracking


grid/CHU

0 0.001966*0.9 kWh

Electricity,lowvoltage,atgrid/CHU 0.002246 0 kWh Steam

Reforming(SR)


grid/CHU

0 0.002246*0.9 kWh

Emissionstoair

Water_kg 0.0178 0.0178*0.9 kg FromSR

Carbondioxide 0.0486 0.0486*0.9 kg FromSR

Emissionstowater

Water_kg 0.012 0.012*0.9 kg

Wastetotreatment

Wastewater,average(CH)|treatmentof,

capacity1.6E8l/year|AllocDef,U

0.045 0.045*0.9 l

Table9:DieselfromwoodfastpyrolysisLCI

4.3 HydrothermalGasification–LCIThisprocessisbaseddirectlyandentirelyonthepaper“HydrothermalGasificationofWaste

Biomass:ProcessDesignandLifeCycleAssessment”(Luterbacheretal.,2009),thatisbased

onacatalytichydrothermalprocessdevelopedhereatthePSI.

Withthisprocess,itispossibletoconvertwastebiomass,suchaswoodwasteormanure,

intorenewableSNG,andtheconversionprocessisdonethroughacatalytichydrothermal

gasificationstage.

Differentscenariosareanalyzedwithinthepaper,butforthepurposeofthisthesisjustthe

large-scalemanuregasificationplant(155MWSNG)andthewoodgasificationplant(35.6

MWSNG)areconsidered.

Ithasbeenthoughtthatthisprocessisactuallyaverypromisingone,becauseitallowsfor

overcomingsomeofthestringentbarrierslinkedwiththebiomass,likethehighcontentof

moistureandaccordinglytheneedofusingmoreenergytodryandprocessit,thereforein

thiswaytheresultisanincreaseintheenergyefficiency.

FortheWoodScenario,thetransportdistanceconsideredisof80kmforcarryingthewood

chipstotheplant,withamoisturecontentof50%.Themoisturecontentthathasbeenused

forthethesisisaboutthe40%,usingthewastewoodchipsprocesspresentintheecoinvent

database.ThecatalystusedintheprocessisaRutheniumcatalyst.Thecompositionofthe

crudegasis50%ofCarbonDioxide(CO2)and50%ofMethane(CH4),thepresenttracesof

hydrogenareconsiderednegligible.TheproducedrawgasisthencleanedorsenttoaHeat

andElectricitystage.ForthecleaningofthesyntheticnaturalgasproducedfromtheCO2,

39

threeprocesseshavebeenconsideredinthepaper:pressureswingadsorption(PSA),

membraneseparationandphysicalabsorption.Thelatterwastheonetakenintoaccount

becauseallowsnotusinganyadditionaldryingstep.

InordertomodelthephysicalabsorptionofCO2intothepolyethyleneglycoldimethyether

(DMPEG),the“DMPEGproductionanddelivery”datasethasbeencreatedbecauseitisnot

presentintheecoinventdatabase.ThisprocessisalsoknownastheSelexolprocess.After

thecleaningtheSNGwillhavethiscomposition:95%CH4and5%CO2,inordertobe

compatiblewiththenaturalgasintothegrid.

TheplantusedinthisprocessisaMethanolone,thisassumptionistakendirectlyfromthe

paperof(Luterbacheretal.,2009),becauseasaplantlikethisdoesnotexistandisnot

availableintheliterature.

ThecatalystusedintheprocessisRutheniumthatisnotpresentintheecoinventdatabase,

thatiswhyaccordingto(Luterbacheretal.,2009)tocalculateittheenvironmentalloadof

theplatinumgroupsmetal(thatisinsteadpresentintheecoinventinventory)hasbeen

used.Theextractionof1kgofRutheniumhasbeenconsideredanditcorrespondstothe

extractionof0.008kgofRhodium,plusadistanceof15’000km,tobeaccountedforthe

transportationfromtheSouthAfricanmines(choseninsteadoftheRussianonesbecauseof

thehigherpresenceofrutheniumintheore),coveredbyplane.

Finally,inthestudyisconsideredanavoidedproductionof0.013kWhofelectricitythatis

producedfromtheprocess.Inordertobeconsistentwiththeotherprocessesthatdonot

haveanyavoidedproductionanexergyallocationhasbeenperformed.Theelectricity

productionhasbeenconvertedfromkWhtoMJ,andtheresultis0.0468MJ.

Thetotalexergyoftheprocessis1MJgas+0.0468MJelectricity=1.0468.Thus,thevalues

mustbemultipliedby(1/1.0468)whichis0.955.

Thesystemboundariesareshownbelow:

40

Image3:WoodHTGsystemboundaries–Source:(Luterbacheretal.,2009)

Thefunctionalunitusedbytheauthoris1MJofSNG,accordingwiththedefinitiongiven

aboveandisperfectlyconsistentwiththeFUchosenforthisthesis.

Theassumptionsmadefortheoptimizedscenarioareconsistenttothosemadeforthe

precedentsprocesses.

BelowisshownthetablecontainingtheLCIusedforthebaselineandoptimizedscenario:

Products Base Optimized Unit CommentMethanefromWoodHTGBaseCase 1 1 MJ

Resources

Water,process,unspecifiednaturalorigin/kg 0.23*0.955 0.23*0.955*0.9 kg Fordiluting

the

woodchips

Materials/fuels

Methanolplant/GLO/IU 1.2853E-12*0.955 1.2853E-12*0.955*0.9 p Proxy

Ruthenium 0.00000014*0.955 0.00000014*0.955*0.9 kg Catalyst

DMPEGproductionanddelivery 1.20E-4*0.955 1.20E-4*0.955*0.9 kg Gas

purification

Transport,lorry20-28t,fleetaverage/CHS 0.0157*0.955 0 tkm

Transport,freight,lorry16-32metric

ton,EURO6AllocRec,U

0 0.0141*0.955 tkm

Wastewoodchips,mixed,fromindustry,

u=40%,atplant/CHU

0.00079*0.955 0.00079*0.955*0.9 m3

Electricity/heat

Heat,naturalgas,atboilermodulating

>100kW/RERU

0.0042*0.955 0.0042*0.955*0.9 MJ

Emissionstoair

Hydrogen 3.94E-7*0.955 3.94E-7*0.955*0.5 kg

41

Carbonmonoxide,biogenic 8.01E-8*0.955 8.01E-8*0.955*0.5 kg HTG

Carbondioxide,biogenic 3.36E-3*0.955 3.36E-3*0.955*0.9 kg HTG

Ethene 7.03E-13*0.955 7.03E-13*0.955*0.5 kg

Ethane 1.41E-8*0.955 1.41E-8*0.955*0.5 kg

Propane 6.36E-12*0.955 6.36E-12*0.955*0.5 kg

Carbondioxide,biogenic 5.71E-2*0.955 5.71E-2*0.955*0.9 kg Gas

Purification

Water 2.21E-6*0.955 2.21E-6*0.955*0.9 m3

Emissionstowater

Ethene 1.19E-14*0.955 1.19E-14*0.955*0.9 kg

Table10:WoodHTG–LCI

4.4 CogenerationHeatandPowerPlant-LCIThisprocessispartoftheecoinventv3.1database.Itreferstoacogenerationplantwitha

capacityof6667kWinSwitzerland,installedin2014.

Heatisthemainproductofthisplant,anditfollowstheheatdemand,whileelectricityisa

co-product.

TheelectricityinthisprocessisproducedthroughanOrganicRankineCycle(ORC)steam

generator(Ecoinvent,2014).

Inthiscasetheassumptionsmadefortheoptimizedcaseare:



Products Base Optimized Unit Comment

Electricity,highvoltage(CH)|heatandpowerco-

generation,woodchips,6667kW

1 1 MJ

Materials/fuels

Water,decarbonised,atuser(GLO)|marketfor|

AllocRec,U

0.0125 0.0125*0.9 kg

Chemical,organic(GLO)|marketfor|AllocRec,U 9.303E-5 9.303E-5*0.9 kg

Chlorine,gaseous|marketfor|AllocRec,U 5.216E-6 5.216E-6*0.9 kg

Sodiumchloride,powder(GLO)|marketfor|Alloc

Rec,U

6.52E-5 6.520E-5*0.9 kg

Lubricatingoil(GLO)|marketfor|AllocRec,U 5.21E-5 5.21E-5*0.9 kg

Ammonia,liquid|marketfor|AllocRec,U 1.304E-7 1.309E-7*0.9 kg

Furnace,woodchips,withsilo,5000kW(GLO)|

marketfor|AllocRec,U

8.282E-9 8.28E-9*0.9 p

NOxretained,byselectivecatalyticreduction(GLO)|


0.00127 0.00127*0.9 kg

Dustcollector,electrostaticprecipitator,forindustrial

use(GLO)|marketfor|AllocRec,U

8.28E-9 8.28E-9*0.9 p

Heatandpowerco-generationunit,organicRankine

cycle,1000kWelectrical(GLO)|marketfor|Alloc

Rec,U

8.282E-9 8.28E-9*0.9 p

Woodchips,wet,measuredasdrymass|marketfor

|AllocRec,U

0.841 0.841*0.9 kg

Emissionstoair Seeecoinvent,

toomanytolist

42

Wastetotreatment

Wastewater,average(GLO)|marketfor|AllocRec,U 1.251E-5 1.251E-5*0.9 m3

Municipalsolidwaste|marketfor|AllocRec,U 5.21E-5 5.21E-5*0.9 kg

Woodashmixture,pure(GLO)|marketfor|Alloc

Rec,U

0.0084 0.0084*0.9 kg

Wastemineraloil(GLO)|marketfor|AllocRec,U 5.216E-5 5.2167E-5*0.9 kg

Table11:ElectricityfromCHP–LCI

TheLCIaboveisabouttheproductionofhighvoltageelectricityfromawoodcogeneration

plant.Toallowthough,itsuseforpoweringanelectriccar,thereistheneedtoconvertit

firsttomediumvoltageelectricityandthefinallytolowvoltageelectricity.

TheLCIsoftheseconversionsaregoingtobeshownbelow:

Products Base Optimized Unit

Electricitymediumvoltagewoodcogenerationplant6667kwh 1 0 MJ

Electricitymediumvoltagewoodcogenerationplant6667kwh

Optimized

0 1 MJ

Materials/fuels

Transmissionnetwork,electricity,mediumvoltage(CH)|

construction|AllocRec,U

1.86E-08 1.86E-08 km

Sulfurhexafluoride,liquid|production|AllocRec,U 5.4E-08 5.4E-08 kg

Electricity/heat

Electricity,highvoltage(CH)|heatandpowerco-generation,wood

chips,6667kW,state-of-the-art2014|AllocRec,U

1.101024 0 kWh

Electricity,highvoltage(CH)|heatandpowerco-generation,wood

chips,6667kW,state-of-the-art2014|AllocRec,U

0 1.101024 kWh

Emissionstoair

Sulfurhexafluoride 5.4E-08 5.4E-08 kg

Table12:ConversionofcogenerationelectricityfromHightoMediumVoltage-LCI


Electricitylowvoltagewoodcogenerationplant6667kwh 1 0 MJ

Electricitylowvoltagewoodcogenerationplant6667kwhOptimized 0 1 MJ

Materials/fuels

Distributionnetwork,electricity,lowvoltage(CH)|construction|

AllocRec,U

8.74E-08 8.74E-08 km


Electricity/heat

Electricitymediumvoltagewoodcogenerationplant6667kwh 1.104 0 kWh

Electricitymediumvoltagewoodcogenerationplant6667kwh

Optimized

0 1.104 kWh

Emissionstoair


Table13:ConversionofcogenerationelectricityfromMediumtoLowVoltage-LCI

43

4.5 HydrogenFromWoodGasification–LCIThisprocessismodelledbasedentirelyonthebook(A.Wokaun,2011).Itconsidersthe

biomassgasificationstartingfromwastewoodchipsfromindustrywith40%ofhumidityat

850°Candatmosphericpressure.AfterittheupgradingprocessusedtoconverttheSNG

producedintoHydrogenistheSteamReforming(SR),thesteamisusedtoenhancethe

hydrogenyield.

TheHydrogenmadeattheendoftheupstreamprocessesisatapressureof30bar.Forthe

furtherusageintoaFuelCellvehiclethisgasiscompressedto700bar.

Fortheoptimizedcasedifferentoperationshavebeencarriedon,astherearemany

processesinvolvedintheproductionofthefinishedfuels.Themodificationsmadearethe

following:

• Increaseoftheprocessefficiencyof10%appliedtoalltheprocessesinvolved(i.e

biomassgasification;SR;hydrogencompression);

• TransportisprovidedbyaEuro6Lorryforthebiomassgasificationprocess;



CH/U”,whichwascreatedfortheThelmaproject(StefanHirschberg,2016).This

modificationhasbeenappliedtoboththebiomassgasificationprocessandthe

steamreformingone;

• ThebiomassgasificationprocessoptimizedhasbeenusedintheSRprocess

optimizedaswell;

• Thehydrogensteamreformingprocessoptimizedhasbeenusedinsteadintothe

compressionofthehydrogenprocessoptimized;

TheLCIsofalltheprocessesaccountedareshownbelow,consideringboththebaseandthe

optimizedcases:

Products Base Optimized UnitSyngas,frombiomassgasification,850°C,1bar,2005/RER 1 1 MJ

Materials/fuels

Woodchips,mixed,fromindustry,u=40%,atplant/RERU 0.000455 4.55E-4*0.9 m3

Rapemethylester,atesterificationplant/RERU 0.000121 1.205E-4*0.9 kg

Magnesium|production|AllocRec,U 0.000152 1.522E-4*0.9 kg

Ironscrap,sorted,pressed|sortingandpressingofironscrap|Alloc

Rec,U

0.000152 1.522E-4*0.9 kg

Lime,packed(CH)|limeproduction,milled,packed|AllocRec,U 0.000343 3.425E-4*0.9 kg

Charcoal(GLO)|production|AllocRec,U 0.000343 3.425E-4*0.9 kg

Zinc,primary,atregionalstorage/RERU 7.82E-06 7.82E-6*0.9 kg


Electricity,lowvoltage,hydropower,2030+,atgrid/CHU 0 2.219E-3*0.9 kWh

Syntheticgasfactory(CH)|construction|AllocRec,U 7.78E-11 7.78E-11*0.9 p

44

Tapwater,atuser/RERU 0.01194 1.194E-2*0.9 kg

Transport,freight,rail/RERU 0.0003 0.0003 tkm

Transport,lorry3.5-20t,fleetaverage/CHS 0.00344 0 tkm

Transport,lorry16-32metricton,EURO6|AllocRec,U 0 0.00344 tkm

Emissionstoair

Oxygen 0.00905 9.05E-3*0.5 Kg

Carbondioxide,biogenic 0.0261 2.61E-2*0.9 Kg

Carbonmonoxide,biogenic 3.34E-05 3.34E-5*0.5 Kg

Nitrogenoxides 1.92E-05 1.92E-5*0.5 Kg

Hydrocarbons,partlyoxidized 3.66E-06 3.66E-6*0.5 Kg

Particulates,>2.5um,and<10um 5.26E-07 5.26E-7*0.5 Kg

Wastetotreatment

Woodashmixture,pure(CH)|treatmentof,sanitarylandfill|Alloc

Rec,U

0.000386 3.86E-4*0.9 Kg

Inertwaste,forfinaldisposal(CH)|treatmentofinertwaste,inert

materiallandfill|AllocRec,U

0.000825 8.25E-4*0.9 Kg

Table14:Biomassgasificationat850°C-LCI

Products Base Optimized UnitH2,gaseous(30bar),fromsteamreformingofbiomassgas,at

reformingplant,2005/RER

1 0 MJ

H2,gaseous(30bar),fromsteamreformingofbiomassgas,at

reformingplant,2005/RER-Optimized0 1 MJ

Materials/fuels

Syngas,frombiomassgasification,850°C,1bar,2005/RER 0.661 0 MJ

Syngas,frombiomassgasification,850°C,1bar,2005/RER-

Optimized

0 0.661 MJ

Steam,inchemicalindustry|production|AllocRec,U 0.044 0.044*0.9 kg

Liquidstoragetank,chemicals,organics(CH)|production|Alloc

Rec,U

1.64E-11 1.64E-11*0.9 p

Chemicalfactory,organics|construction|AllocRec,U 8.01E-12 8.01E-12*0.9 p

Electricity/heat



Emissionstoair

Carbondioxide,biogenic 0.12 0.12*0.9 kg

Table15:HydrogenfromSteamReforming-LCI

Products Base Optimized UnitHydrogen,gaseous,frombiomassgasificationandSMR,700bar,

2005/RERU_Saverio

1 1 MJ

Materials/fuels

hydrogenfuellingstation,nostaticstoragefacility2005/RER/IU 1.4E-09 1.4E-09*0.9 p

operation,hydrogenfuellingstation2005/RERU 0.185 0.185 hr

disposal,hydrogenfuellingstation2005/RER/IU 1.4E-09 1.4E-09*0.9 p


reformingplant,2005/RER

6.9E-05

0 MJ


reformingplant,2005/RER-Optimized

0 6.9E-05*0.9

MJ

Hydrogencompression,30to700bar,2005 6.9E-05

6.9E-05*0.9

MJ

Table16:Hydrogencompressionto700bar–LCI

45

5. LCIoftheProcessesUsingManureBiomass

Inthischapterthedifferentpathwaysforprocessingmanurebiomasswillbepresented.All

oftheseprocessesaretakenfromtheecoinventdatabase.Thecontributionfromthisthesis

totheseprocessescanbeweighedintheoptimizedscenarioanalysis,wheresomeofthe

assumptionsmadebeforeinthemethodchapterareherethereforeapplied,andwillbe

exactlyexplainedinthefollowingsubchapters.

Aflowchartexplainingthepathwaysinvestigatedispresentedbelow:

Flowchart2:ManureBiomassPathways

46

5.1BiogasProductionandMethanation–LCIThisprocessconsideredispartoftheecoinventdatabase,andiscompletelydocumentedin

thereport“Analysedecycledeviedelaproductioncentraliséeetdecentraliséedebiogaz

enexploitationsagricoles”(DauriatA.,2011).

InthischaptertheLCIsoftheproductionofbiogasfromsolidcattlemanureandbiowaste,

anditsupgradetonaturalgassothatitcanbeusedasacar’sfuelwillbebrieflyexposed.

TheplantconsideredisbasedonthestudyofseveralSwissfermentationplantsconsidering

alifetimeoftheplantof20years.

Belowthesystemboundarieswillbeshown:

Figure4:Biogasproductionboundaries–Source:(M.Spielmann,2006)

Thebiogascompositionfromthisprocessissodivided:

Compounds Unit ValueMethane Vol% 67

CarbonDioxide Vol% 32.05

Methane Kg/Nm3 0.4

CarbonDioxide Kg/Nm3 0.6

TotalCarbonContent Kg/Nm3 0.5

Nitrogen Vol% 0.7

Density Kg/Nm3 1.12

LowerHeatingValue MJ/Nm3 24.04

Table17:Biogascomposition

ThepurificationprocessoftheBiogas(alsoknownasbiogasupgrade)hasbeentakenfrom

theecoinventreport“LifeCycleInventoriesofBioenergy”chapter13((M.Spielmann,2006;

Spiellmann,2005),andtheLCIusedistheonepresentintheecoinventdatabase.Afterthis

purificationprocessthegascompositionwillbeequaltothatofnaturalgas,andforthe

purposeofthethesiswillbeconsideredforpoweringamid-sizednaturalgascar.

FortheproductionoftheBiomethanethemainoperationstobecarriedoutare:

• RemovalofCO2

• RemovalofH2SandWater(forcorrosionproblemstheycause)

47

Amongthedifferentwaystoremovethosecompounds(e.g.gasscrubbing,adsorption,

membraneseparation)inthisprocess,thePressureSwingAdsorption(PSA)processhas

beenadopted,andthetechnicalcharacteristicsofitaretakenfromatypicalSwissplant:the

Rütgersplant(2004).Belowaflowchartexplaintheprocesswillbeshown:

Image5:Biogascleaningandupgradingflowchart-Source:(M.Spielmann,2006)

Asfortheothercases,manyoftheassumptionsmadefortheoptimizedscenarioarehere

applied.

Theefficiencyoftheupgradingprocessofthisprocesshasbeenconsideredhigher

accordingtothepaperswrittenby(Alonso-Vicarioetal.,2010;Cavenati,Grande,&

Rodrigues,2005).Cavenatietal.foundoutthatacarbonmolecularsieve(CH4/CO2=55/45,

volumebasis)at303Kand320kPacanreachamethanepurityhigherthan96%andthat

therecoveryratecanbeof75%.Alonso-Vicarioetal.insteadtestedtheCO2absorption

capacityofnaturalzeoliterespecttothesyntheticoneshowingadoubleabsorption

capacity.

Furthermore,itisassumedthatthemethaneyieldfromtheanaerobicdigestionplantcan

beimprovedconsideringdifferentenhancements.

AccordingtoProf.UrsBaierfromZHAWuniversitywecanstatethat:(Baier,13.10.2016):

• Specificsubstratetreatmentmightallowdoublingthebiogas(i.e.themethane)yieldonthatspecific

substrate.

• Processcontrolpermitstoenhancetheefficiencyofthewholeplant,whichis:morethroughputsper

volumeorlessvolumeforthesamethroughputs.Itcanberoughlyestimatedanincreaseof

volumetricefficiency(volumegasproducedpervolumedigester)ofonethird(30-35%)byapplying

advancedprocesscontrol.

• Bioreactordesignandoperationincludingon-lineanalyticscanhavethesameeffect;togetmore

methaneoutofasubstrateatashorterresidencetimeorwithsmallfermentervolumes.This

enhancementmightleadtoanincreaseintheefficiencybetween20%and400%,whichis20%more

biogasinagivenvolume(or20%lessvolumeforanequalamountofbiogas)uptothesameamount

48

ofbiogasinafour-timesmallervolume(thoughnotfourtimesmorebiogaswhichwouldbe

stoichiometricallyimpossible.

Foranexistinginstallation,itispossibletoconsideranincreaseofthemethaneproducedby40-65%.

ItcanbepossiblethattheassumptionsofProfessorBaieraretoooptimisticandthatthe

truthmightresidesamongourbaseandoptimizedcase.

Inthelightoftheseconsiderationsourbiogasproductionhasbeenenhancedinthe

optimizedcaseaccordingwiththesuggestionsofProf.Baier,andthePSAstephasbeen

enhancedaswellbya10%accordinglytotheaforementionedpapers,andtheassumptions

madeinsub-chapter3.6,fortheoptimizedscenario.

HerebyaretheLCIsofthebiogasproductionandsubsequentupgraderespectively:

Products Base Optimized Unit CommentBiogas(CH)|treatmentofmanureandbiowasteby

anaerobicdigestion,frommanure,liquid

1 1 m3

Materials/fuels

Manure,solid,cattle(GLO)|marketfor|AllocRec,U 38.93094 38.93*.5 kg

Digestersludge(GLO)|digestersludge,RecycledContent

cut-off|AllocRec,U

-86.6373 -86.6373*.5 kg Linearly

scaled

Anaerobicdigestionplant,agriculture,withmethane

recovery(GLO)|marketfor|AllocRec,U

2.86E-07 2.86E-7*.70 p

Glycerine(GLO)|marketfor|AllocRec,U 0.043213 0.043213*.5 kg

Electricity/heat

Heat,centralorsmall-scale,otherthannaturalgas(CH)|


3.47 3.47*0.7 MJ

Electricity,lowvoltage(CH)|marketfor|AllocRec,U 0.158 0 kWh


Emissionstoair

Hydrogensulfide 4.32E-05 4.32E-5*0.5 kg

Ammonia 0.001693 0.001693*0.5 kg

Dinitrogenmonoxide 0.000108 0.000108*0.5 kg


Methane,biogenic 0.055 0.055*0.5 kg

Table18:Biogasproductionfrommanure&biowaste–LCI

Products Base Optimized Unit CommentMethane,96%byvolume(CH)|treatmentofbiogas,

purificationtomethane96vol-%|AllocRec,USaverio

1 1 MJ

Materials/fuels

Biogas(CH)|treatmentofmanureandbiowasteby

anaerobicdigestion,frommanure,liquid,cattle|AllocRec,

UBase

0.043

0.043*0.9 m3 10%

increase

process

efficiency

Chemicalfactory,organics(GLO)|marketfor|AllocRec,U 1.16E-11

4E-10*0.9 p

Electricity/heat

Electricity,lowvoltage,atgrid/CHU 0.014

0 kWh


49

Emissionstoair

Sulfurdioxide 1.6E-05 1.6E-05*0.5 kg


Hydrogensulfide 1.01E-07 1.01E-07*0.5 kg

Methane,biogenic 6.4E-4 6.4E-4*0.5 kg

Table19:Methanefrommanurebiogascleaning-LCI

5.2BiogasEngineCo-generation–LCI

Thisprocessisaboutasmallcogenerationplantbasedontheecoinventreport“LifeCycle

InventoriesofBioenergy”(M.Spielmann,2006),buttheoperatingdatahavebeenupdated

in2014,andispossibletofinditintheecoinventdatabase.Respecttotheoriginalprocess

insteadofusingasinputoftheprocessbiogasfromsewageandbiowaste,ithasbeenused

thebiogasproducedfromliquidcattlemanure.Thelowerheatingvalueofthisbiogasis

assumedtobethesameoftheonestatedintheecoinventdatabase,andisequalto22.73

MJ/Nm3.

Asitisacogenerationplanttherearetwoproducts,highvoltageelectricityandheat,thus

anexergyallocationhasbeenconsidered.Usingthisallocationmethodtheelectricitywhich

isahigherformofenergywillcarryaheavierenvironmentalburdenrespecttotheheat.

Theassumptionsusedfortheoptimizedcasearethefollowing:

• Increaseoftheprocessefficiencyby10%;


TheLCIisthefollowing:

Products Base Optimized UnitElectricity,highvoltage(CH)|heatandpowerco-generation,biogas,

gasengine|AllocRec,U

1 1 kW

h

Materials/fuels

Heatandpowerco-generationunit,160kWelectrical,common

componentsforheat+electricity(GLO)|marketfor|AllocRec,U

3.3E-08 3.3E-8*0.9 p

Heatandpowerco-generationunit,160kWelectrical,components

forelectricityonly(GLO)|marketfor|AllocRec,U

3.3E-08 3.3E-8*0.9 p

Heatandpowerco-generationunit,160kWelectrical,components

forheatonly(GLO)|marketfor|AllocRec,U

3.3E-08 3.3E-8*0.9 p

Biogas(CH)|treatmentofmanureandbiowastebyanaerobic

digestion,frommanure,liquid,cattle|AllocRec,UBase

0.29 0.29*0.9 m3

Lubricatingoil(GLO)|marketfor|AllocRec,U 2.02E-4 2.02E-4*0.9 kg

Emissiontoair

Platinum 4.7E-11 4.7E-11*0.5 kg

Dinitrogenmonoxide 1.6E-05 1.6E-5*0.5 kg

Carbonmonoxide,biogenic 3.2E-4 3.2E-4*0.5 kg


Nitrogenoxides 1.01E-4 1.01E-4*0.5 kg

50

NMVOC,non-methanevolatileorganiccompounds,unspecified

origin

1.34E-05 1.34E-5*0.5 kg

Sulfurdioxide 1.4E-4 1.4E-4*0.5 kg

Methane,biogenic 1.5E-4 1.5E-4*0.5 kg

Wastetotreatment

Wastemineraloil(GLO)|marketfor|AllocRec,U 2.02E-4 2.02E-4*0.9 kg

Asithasbeenstatedinsub-chapter4.4,alsointhiscasetheelectricityproduced,mustbe

convertedtolowvoltagebeforeitsuseforpoweringanelectriccar.TheLCIofthese

conversionsaredisplayedbelow:


Electricitymediumvoltagebiogasengine 1 0 kWh

ElectricitymediumvoltagebiogasengineOptimized 0 1 kWh

Materials/fuels

Transmissionnetwork,electricity,mediumvoltage(CH)|construction|

AllocRec,U

1.86E-08 1.86E-08 km


Electricity/heat

Electricity,highvoltage(CH)|heatandpowerco-generation,biogas,gas

engine|AllocRec,U

1.101024 0 kWh

Electricity,highvoltage(CH)|heatandpowerco-generation,biogas,gas

engine|AllocRec,UOptimized

0 1.101024 kWh

Emissionstoair


Table20:Conversionfromhightomediumvoltagebiogaselectricity-LCI


Electricitylowvoltagebiogasengine 1 0 kWh

0 1 kWh

Materials/fuels

Distributionnetwork,electricity,lowvoltage(CH)|construction|Alloc

Rec,U

8.74E-08 8.74E-08 km


Electricity/heat

Electricitymediumvoltagebiogasengine 1.104 0 kWh

ElectricitymediumvoltagebiogasengineOptimized 0 1.104

Emissionstoair


Table21:Conversionfrommediumtolowvoltagebiogaselectricity

5.3HydrothermalGasificationofManureBiomass–LCIThisprocesshasbeenbasedonthepaper“HydrothermalGasificationofWasteBiomass:

ProcessDesignandLifeCycleAssessment”(Luterbacheretal.,2009).Ithasbeenincluded

intothisthesisbecauseusestheHydrothermalGasification(HTG)process,thatisbelieved

tobeoneofthemostpromisingone,especiallywhendealingwithwetbiomass,asthe

solventusedwithintheprocessisthewateritselfinitscriticalconditionsorabovethem.

51

Thismeansthatthereisnoneedtodry-upthebiomassbeforeprocessingit,avoidingusing

energyandheatfordoingthisintensiveoperation.

Theassumptionsmadefromtheauthorsforthestudyofthislargescalemanurebiomass

plant(155MWelsize)arethefollowing:

• Twotransportfacilitiesareconsideredforcollectingthebiomasstotheplant:freight

train(forthelongdistance:83km)andtractor(tocovertheshortdistancefromthe

farmtotherailstation:5km);

• Themanureusedforproducingthebiofuelisanavoidedactivityasthemanureis

notspreadontheground;

• Ifmanureisnotspread,thesoilwillneedafertilizertoreplaceit.Butasthemineral

fertilizerusedtoreplacemanureis1.55timesmoreefficient,insteadofreplacing

theexactquantityofmineralsthatarepresentin1kgofmanurethatis312g,just

113gofmineralfertilizerarereplaced,consideringanefficiencyofitof100%.

Despitetheassumptionscarriedoninthepapersomeoftheseassumptionshavebeen

neglectedinthisthesisintheeffortcarriedontoharmonizetheassumptionsacrossvarious

papersanddatasources.Asintheotherprocessesconcerningtheproductionofbiogasor

methane,startingfrommanure,theassumptionthatthebiomassconvertedtobioenergyis

notusedforfertilizingthesoilisnotincluded,weavoidusingit.

Notincludingthisassumptionthoughwillmakeourresultstobeverydifferentfromthose

ofthestudyonwhichourcalculationsarebasedon.Includingthefertilizerproductionfor

nothavingspreadthemanuretothesoil,wouldhaveheavilyaffectedalltheimpact

categoriesbyusexplored.Thisisbecausethecontributionofthisprocesswouldhavenot

madepossibletoarrivetoanyconclusion,asalltheotherinputsandoutputsincludedinthe

HTGprocesswouldhavebeenobscuredbythefertilizersproduced.

Furthermore,intheprocessthereisanoverproductionofelectricityfromtheburningof

partofthemethaneproduced.Theamountofelectricitythatgoestothegridis

6.2 ∙ 10-./0ℎperMJofmethaneproduced,equalto0.002232MJ.Thetotaloutputproductionisthus1.002232MJ.Anexergyallocationofthiselectricityhasbeencarriedon,

sothattheotherprocessesconsideredarefullycomparablewiththisone.Alltheinputsand

outputsoftheprocesshavebeenthusmultipliedby(1/1.002232)=0.997.

Theprocessusedisthesameoneusedinthesubchapter4.3,onlytheassumptionsatthe

baseofit,astherawbiomassisdifferent,havebeenchanged.Theplantusedisan

approximationone,asnodataareavailableforthestructure,andagainforcleaningthegas

aphysicalabsorptionprocessistakenintoaccount.

Thesystemboundariesandtheoperationsdescribingtheprocessareshownunderneath:

52

Image6:ManureHTGsystemBoundaries-Source:(Luterbacheretal.,2009)

ThepurificationofthegashasbeendonehereaswellusingthePSAprocess.

Inouroptimizedcasetheassumptionaccountedare:



• TransportisprovidedbyaEuro6Lorry;



CH/U”,whichwascreatedfortheThelmaproject(StefanHirschberg,2016);

BelowwillbedisplayedtheLCIoftheprocess:

Products Base Optimized Unit CommentBiomethane,manureHTG 1 1 MJ

Resources

Carbondioxide,inair 5.46*0.997 4.914*0.997 kg 1.3kgCO2

perkg

manuredry

mass

Materials/fuels

Transport,lorry3.5-20t,fleetaverage/CHS 0.0042*5*0.997 0 tkm Proxyfor

theTractor

53

Transport,freight,lorry16-32metricton,EURO6|

AllocRec,U

0 0.00378*5*0.997 tkm Proxyfor

theTractor

Transport,freight,rail/CHU 0.0042*83*0.997 0.00378*83*0.997 tkm Train

Methanolplant/GLO/IU 1.25E-11*0.997 1.25E-11*0.997 p Proxy

Ruthenium 1.4E-7*0.997 1.4E-7*0.997*0.9 kg

DMPEGproductionanddelivery 1.10E-4*0.997 1.10E-4*0.997*0.9 kg Gas

purification

–Physical

Adsorption

Heat,naturalgas,atboilerfanburnernon-

modulating<100kW/RERU

0.0031*0.997 0.0031*0.997*0.9 MJ

Manure,solid,cattle(GLO)|marketfor|Alloc

Rec,U

4.2*0.997 4.2*0.9*0.997 kg

Emissionstoair

Hydrogen 6.6E-7*0.997 6.6E-7*0.997*0.5 kg

Carbonmonoxide,biogenic 1.59E-7*0.997 1.59E-7*0.997*0.5 kg

Carbondioxide,biogenic 5.63E-2*0.997 5.63E-2*0.997*0.9 kg

Ethene 1.56E-12*0.997 1.56E-

12*0.997*0.5

kg

Ethane 1.28E-8*0.997 1.28E-8*0.997*0.5 kg

Propane 5.66E-12*0.997 5.66E-

12*0.997*0.5

kg

Carbondioxide,biogenic 5.2E-2*0.997 5.2E-2*0.997*0.9 kg

Water 6.72E-7*0.997 6.72E-7*0.997*0.5 m3

Emissionstowater

Ethene 2.66E-14*0.997 2.66E-

14*0.997*0.5

kg

ThecatalystusedintheprocessisRutheniumthatisnotpresentintheecoinventdatabase,

thatiswhyaccordingto(Luterbacheretal.,2009)tocalculateittheenvironmentalloadof

theplatinumgroupsmetal(thatisinsteadpresentintheecoinventinventory)hasbeen

used.Theextractionof1kgofRutheniumhasbeenconsideredanditcorrespondstothe

extractionof0.008kgofRhodium,plusadistanceof15’000km,tobeaccountedforthe

transportationfromtheSouthAfricanmines(choseninsteadoftheRussianonesbecauseof

thehigherpresenceofrutheniumintheore),coveredbyplane.

54

6.LCIofAlgaeProcesses

InthischaptertheLCIsofalltheprocessesinvestigatedforthecultivationofthealgaeand

totheproductionofthefinishedfuelaredisplayed.Thissectionisincludedwithinthisthesis

fortwofoldreasons.Thefirstisbecausethisbiomassrepresentsthefutureasthepotential

withinthealgaeisrichbutasyetnotfullyexploited.Thesecondoneisbecauseitisto

believethatevenifthistechnologyisnotyetreadyforlarge-scaleproduction,itishowever

truethatwithsomeimprovementsandfurtherresearchthispathwaywouldbethemost

promisingoneinthenextgeneration.Howevertheproductionofthisbiofuelswillnotbe

locatedinSwitzerland,butinItalybecauseofthenon-optimalweatherconditions,therefor

inthefollowingprocessestheItalianelectricityaveragemixwillbeused.Alsothetransport

ofthefinishedfuelfromItalytoSwitzerlandisconsideredandisdonebytrain.Thelengthof

thetripisestimatedtobe960km(countingthedistancefromcapitaltocapital).

Amongtheadvantagesrepresentedbythisrenewableformofbiomasswecanconsider:

• Biomassaccumulationrateoneorderofmagnitudesuperiorcomparedtoterrestrial

cropsperunitoflandarea(Richard,2010);

• Higherphotosyntheticefficiency,cultivationonnon-arableormarginalland(Brown,

Brown,Duan,&Savage,2010)

• Extremelyhighoilyields,thatisadesirablecharacteristicforproducingbiodiesel

(Chisti,2007);

Unfortunatelydespitetheseremarkableadvantagescomparedtorenewablebiomass,algae

productionisstillveryexpensive,andfurtherresearchesmustbedonetowardthissubject,

alsodisadvantagescharacterizetheirproduction.

Untiltodayalgaearecultivatedandprocessedtoachievedifferenthighrevenueproducts,

usableinthepharmacyoralimentarysector,notforproducingbiofuels.Thismeansthat

bettercultivationandharvestingmethodmustbediscovered.

Furthermorethefertilizersusedforthegrowthofthealgaemustbeintensivelyrecycled,as

theycanheavilyimpacttheenvironment,whilethebiomassproductivityandtheoilyield

mustbeimproved.

Forincreasingtheresilienceofthealgaefrompathogensorpredatorshybridizationand

molecularmodificationsarerequired.Furthermoregeneticmodificationcanbeavalidhelp

forincreasingthebiomassandoilproductivity.

Anotherinterestingwaytomakeadvancesforthistechnologyistoco-locateitnearto

powerplants,inordertoexploittheexhaustflueorCO2gasesasasourceofnutrients,but

alsoitispossibletoconceivetheseplantsclosetowastewaterplantorwastenutrients

flows(Passelletal.,2013;Zhouetal.,2014).

Fortheoptimizedscenariotheprocessesinvestigatedinthisworkweassumeanincreasein

biomassproductivity,theuseofrenewableelectricity,animprovementintheprocess

55

efficiency,andtheco-locationofthefacilitytoapowerplant,butspecificdetailswillbe

givencasebycase.

Asummarizingtableofalltheprocessesinvestigatedisherebypresented:

CultivatingSystem

AlgaeStrain Optimization

BiomassProductivity[g/m2/d]

OilContent[kgoil/kgdb]

ExtractionMethod

Co-product

Fuel

OpenPond

Race(OPR)

Nannochlorissp.andNannochloropsissp.

No 3 0.24 SolventExtraction

(Hexane)

No Diesel

OpenPond

Race(OPR)

Nannochlorissp.andNannochloropsissp.

Yes 25 0.50 SolventExtraction

(Hexane)

No Diesel

OPR+

PhotoBio

Reactor

(PBR)

Staurosirasp. No 19 0.31 SolventExtraction

(Hexane)

No Gasoli

ne

OPR+

PhotoBio

Reactor

(PBR)

Desmodemussp. Yes 23 0.38 HydroThermal

Liquefaction

No Gasoli

ne

OPR+

PhotoBio

Reactor

(PBR)

Desmodemussp. Yes 23 0.38 Solventextraction

(Heptane)

Yes Gasoli

ne

Table22:Algaepathwayssummarizingtables

Aflowchartpresentingthedifferentpathwaysexploredispresentedbelow:

56

Flowchart3:AlgaePathways

57

6.1BiodieselfromOpenPondsRacesThischapterisaboutthecultivationofmicroalgaeinanOpenPondsRace(OPR)andis

modelledbasedonthepaperof(Passelletal.,2013),whoseworkhasbeenadaptedforthe

purposeofthethesistoinvestigatetheproductionofabiofuelfromalargescalefacility,

becausetheoriginaldatausedareofanexistingplantof0.1hascaleduptoa10haplant,

usingcurrentcommercialdata.

Inthescalingupdifferentassumptionsaremadeforincreasingthecurrentproduction,like

higherproductionefficiencyduetothebiggerproductionfacilityandtheprogressesinto

thecultivationandharvestingmethod,togetherwithahigherbiomassproductivitythat

goesfrom3g/m2/dto25g/m

2/d.Thesearethevaluesadoptedforthebaseandoptimized

case,andtheyrepresentthecurrentproductivityofanexistingcommercialfacility(at

SembioticInc.inAshkelon,Israel)andthemaximumproductivityaccordingwiththe

literaturerange(Passelletal.,2013).

Image7:OpenPondRaces-Source:Wikipedia

Theplantisco-locatedtoapowerplantthatisthesourceofCO2andforeverykgof

biomassproduced2kgofitareabsorbed,asitwillrepresentasourceofcarbonforthe

algae’sgrowth.Notransportsorinfrastructuresareincluded,howeverforagreater

thoroughnesstheyhavebeenadded,usingthedatafromthestudyof(Muetal.,2014)and

theassumptionmadeinthepreviouschapter.

ThealgaestrainsusedareNannochlorissp.andNannochloropsissp.whilethewaterusediswasteseawatercomingfromthenearbypowerplantwithasalinityof35g/L.

Afterthecultivationstepthealgaearecentrifugedandreducedtoasolutionwith20%

solids.Theprocessusedisawetextractionmethoddividedthus:

• Pretreatment

• Extraction

• Solventrecovery

• Oilseparation

58

• Beltfilterpress

• Feeddryer

Thesolventusedishexane,whichisafterrecovered,evenifapartofitislostintheairas

fugitiveemissions.Thissolventisrequiredforextractingtheoilcontainedinthealgae.

Thelasttwostepsareneededforthedewateringanddryingoftheremainingbiomass.

Theoilextractedisthenfurtherupgradedintoafinishedfuel(i.e.biodiesel)througha

transesterificationprocess.Eventhoughthisprocessisnotpresentintheecoinvent

database,ithasbeenadaptedwiththeexistingprocessofthetransesterificationofthe

soybeanoil.Forthisreason,theoriginalecoinventprocesshasbeenupdatedforthe

purposeofthisthesis,andsoinsteadofconsideringtheesterificationplantintheUnited

States(US)weconsideritinthecenterofItaly.Adistanceof960km(i.e.distancefrom

RometoBern)iscoveredbytrain.Thenfortheregionaldistributionofthefinishedfuelwe

maintaintheassumptionsoftheecoinventprocessconsideringadistanceof150kmbyroad

coveredbyalorry,andadistanceof100kmcoveredbytrain.

TheelectricitymixusedistheItalianaverageoneatgrid,asithasbeensaidinthe

introductionchapterthatSwitzerlandisnotasuitableareaforthecultivationofAlgae,

whilethesouthernpartsofEuropeornorthernpartsofAfricacanbeagoodcompromise

betweentheweatherconditionsandthedistancefortransportingthefinishedfuel.

Withinthewetextractionprocesstwoco-productsareproducedtogetherwiththealgaeoil,

lowvaluelipids(Hydrocarbons)andtheresidualbiomass(oilcake).Theallocationofthe

impactsoftheco-productsismadeconsideringtheenergycontentofthem.

Theenergyallocationpercentagesusedinthestudyof(Passelletal.,2013)arethe

following:

Co-product PercentageAllocationCrudealgae-oil 42%

Hydrocarbons 28%

Oilcake 30%

Table23:Energybasedallocationratiosperkgcrudealgaeoil–Source:(Passelletal.,2013)

Anenergyallocationconsideringthecrudealgae-oilhasthusbeenperformed.The

coproductscanbeusedindifferentways,likeanimalfeeding,ortheycanbeusedinthe

pharmacyandalimentarysector,havingahighrevenuevalue.

Intheoptimizedcaseaccordingto(Passelletal.,2013)thesearetheimprovementsmade:

• Thepaddlewheels(thatareusedforcontinuouslymixingtheOPRandallowingthe

spreadofthenutrientssubstances),scalefrom7.5kWinthe1000m2facilityto5.8

kWforeachoftheminthe10haone(i.e.50paddlewheelforeverypondsized

2000m2);

59

• Waterpumpandblowerenergyscalelinearly;

• Algaeproductivityincreasesfrom3g/m2/dto25g/m

2/d;

• 4centrifugesat4kWarerequiredtoreducewatervolumeinthebiggerfacility;

• Higheroilcontent:from0.24kgoil/kgdryalgaebiomassto0.5kgoil/kgdryalgae

biomass;

• Renewablesourceofenergy:forbeingconsistentwiththeotheroptimizedcases

exploredweusethesameelectricity,whichisthelowvoltagehydropowerone,

createdfortheThelmaproject(StefanHirschberg,2016);

• InthetransesterificationprocessthetransportsonroadsareprovidedbyaEURO6

lorryandtheatmosphericemissionshavebeenreducedto50%;

Alltheseassumptionsarevalidonlyforthecultivationandharvestingprocesses,notforthe

oilextractionone.

AlgaecultivationandoilextractionarecountedinthesameLCIdatasetasitwasperformed

originallybytheworkof(Passelletal.,2013).Thevaluesforthecultivationstepare

accountedperkg-1drybiomass:

Products Base Optimized Unit Comment

AlgaeOilOPRBaselineCase(3g/m2/d) 1 1 kg

Resources

Water,process,unspecifiednatural

origin/m3

0.706 0.706 m3 Addedtocontrastthewater

evaporationandtomantain

salinitytospecificlevel

Carbondioxide,inair 2 2 kg Fromtheco-locatedpowerplant

asasourceofC

Electricity/Heat

Electricity,lowvoltage,productionIT,at

grid/ITU

12.676 0 kWh Paddlewheels

Electricity,lowvoltage,hydropower,

2030+,atgrid/CHU

0 0.582 Paddlewheels


grid/ITU

5.07 0 kWh Fluegasblower


2030+,atgrid/CHU

0 30.121 Fluegasblower


grid/ITU

1.408 0 kWh Waterpump


2030+,atgrid/CHU

0 0.167 Waterpump


grid/ITU

2.86 0 kWh Algaeinoculantprep(florescent

light)


2030+,atgrid/CHU

0 0.17 Algaeinoculantprep(florescent

light)


grid/ITU

2.52 0 kWh Algaeinoculantprep(air

conditioner)


2030+,atgrid/CHU

0 0.15 Algaeinoculantprep(air

conditioner)


grid/ITU

0.845 0 kWh Harvestingpump


2030+,atgrid/CHU

0 0.05 Harvestingpump


grid/ITU

6.761 0 kWh Centrifuge-Dewatering

60


2030+,atgrid/CH

0 0.04 Centrifuge-Dewatering

Electricity,lowvoltage,atgrid/ITU 0.089 0 kWh SRSprocess(OilExtraction)-

electricityperkgoil


2030+,atgrid/CHU

0 0.089 SRSprocess(OilExtraction)-

electricityperkgoil

Heat,naturalgas,atindustrialfurnace

>100kW/RERU

2.19 2.19 MJ Energyusedforthepretreatment

andextractionoftheoilperkgoil


>100kW/RERU

2.79 2.79 MJ Energyinputforrecoveringthe

hexaneperkgoil


>100kW/RERU

0.805 0.805 MJ Energyinputforprocessingof

theoiltoseparatetheoiland

otherlipids

Electricity,lowvoltage,atgrid/ITU 0.845 0.845 kWh ElectricityBeltFilterPress,used

todewaterthebiomass


>100kW/RERU

2.86 2.86 MJ FeedDryer-Electricityfordrying

thebiomass

Materials/fuels

Diammoniumphosphate,asN,at

regionalstorehouse/RERU

0.11 0.11 Kg Fertilizer–thequantityisfixed

pergofalgaebiomass

Diammoniumphosphate,asP2O5,at

regionalstorehouse/RERU

0.019 0.019 kg Fertilizer–thequantityisfixed

pergofalgaebiomass

Polyethylene,linearlowdensity,

granulate|production|AllocRec,U

0.003 3.01E-05 kg Infrastructure

Steel,unalloyed(GLO)|marketfor|

AllocRec,U

0.00177 1.75E-05 kg Infrastructure

Concrete,normal(GLO)|marketfor|

AllocRec,U

5.49E-

06

5.43E-08 m3 Infrastructure

Hexane(GLO)|marketfor|AllocRec,U 0.139 0.139 kg Solventused

Chemical,organic(GLO)|marketfor|

AllocRec,U

0.034 0.034 kg Proxy-Unknownorganicusedin

theprocess

Emissionstoair

Water 0.706 70.578 m3 Evaporation

Hexane 0.002 0.002 kg Fugitiveemissionsinthe

extractionprocessoftheoil

Wastetotreatment

Wastewaterfromvegetableoilrefinery(GLO)|treatmentof|AllocRec,U

7.331 7.331 l Proxy–wastewaterfromtheoil

extractionprocess

Table24:Algaecultivationandoilextraction–LCI

61

TheLCIofthetransesterificationprocessofthealgaeoilinthebaseandoptimizedcaseis

insteadthefollowing:


BiodieselfromEsterificationprocess 1 1 MJ

Materials/fuels

AlgaeOilOPRBaselineCase(3g/m2/d) 2.63E-02

0 kg

AlgaeOilOPROptimized(25g/m2/d) 0 2.63E-02

kg

Electricity,lowvoltage(IT)|marketfor|AllocRec,U 1.76E-04

0 kWh

Electricity,lowvoltage,hydropower,2030+,atgrid/CHU

0 0.0067 kWh

Lightfueloil,burnedinboiler100kW,non-modulating/CH

U

1.63E-05

0.000621 MJ

Transport,freighttrain(IT)|processing|AllocRec,U 0.025

0.025

tkm

Transport,freighttrain(CH)|electricity|AllocRec,U 2.63E-03 2.63E-03 tkm

Transport,lorry20-28t,fleetaverage/CHU 3.95E-03

0 tkm

Transport,freight,lorry16-32metricton|AllocRec,U 0 3.95E-03

tkm

Regionaldistribution,oilproducts/RER/IU 6.89E-12

6.89E-12

p

Tapwater,atuser/CHU 1.8E-05 1.8E-05 kg

Emissionstoair

Heat,waste 6.34E-04

6.34E-04

MJ

BOD5,BiologicalOxygenDemand 9.2E-5

9.2E-5*0.5 kg

COD,ChemicalOxygenDemand 9.2E-5

9.2E-5*E-5

kg

DOC,DissolvedOrganicCarbon 1.13E-05

1.13E-05*0.5

kg

TOC,TotalOrganicCarbon 1.13E-05 1.13E-05*0.5 kg

Emissionstosoil

Oils,biogenic 1.32E-05

1.32E-05

*0.5

kg

Wastetotreatment

Disposal,separatorsludge,90%water,tohazardous

wasteincineration/CHU

4.41E-06

4.41E-06

kg

Disposal,municipalsolidwaste,22.9%water,tosanitary

landfill/CHU

1.64E-07

1.64E-07

kg

Treatment,rainwatermineraloilstorage,towastewater

treatment,class2/CHU

1.97E-06

1.97E-06

m3

Treatment,sewage,towastewatertreatment,class2/CH

U

1.81E-08 1.81E-08 m3

62

6.2GasolinefromAlgae100hafacilityInthischapterthecultivationofthealgaeina100hahybridsystemfacility(i.e.apartis

madewithPhotobioreactors(PBRs)andtheotheronewithOPRs)iscarriedoutinorderto

exploitthemaximumadvantagesprovidedbythesetwocultivationsystems.Themodelling

isbasedonthepaperwrittenby(Bealetal.,2015).Thesystemmodelledbytheauthorsis

basedonanoriginaldemonstrationplantof0.5hascaledup(i.e.KonaDemonstration

Facility(KDF)nowCellanaLLC).Twoalgaespeciesweretherecultivated:Staurosirasp.andDesmodemussp.,withbiomassproductivityrespectivelyof19g/m

2/dand23g/m

2/d,

evaluatedthroughthedemonstrationplant.Thislarge-sizefacilityisassumedtobeneara

powerplant,toexploititswastestreamgasesasasourceofcarbon,whilethefertilizersare

assumedtobebought.

TwoimagesarepresentedbelowtoshowthereaderhowaPBRlookslikeandhowis

designedthesystemfacility:

Image8:Photobioreactor

63

Image9:Systemfacility-Source:(Bealetal.,2015)

Manyprocessesareexploredwithinthestudyof(Bealetal.,2015),butthoseonwhichwe

aregoingtoconcentratearethree:

1. Aprocessusingthecurrenttechnologiesforcultivationandharvesting,adoptinga

solventfortheoilextraction;

2. Aprocesswithenhancedharvestingandcultivatingprocessesandtheoilextraction

methodisbasedonthehydrothermalliquefaction(HTL);

3. Aprocessequaltothesecondoneexceptfortheoilextractionmethodthatisbased

onaprocessnamedOpenalgae.Inthisoneelectromagneticsforcesareusedfor

splittingthealgae’scellsallowinganeasierrecoveryoftheoilextracted.

Thesecondandthirdprocessesarealreadyconsideredoptimizedbytheauthorsofthe

paperandeachoftheseprocessesiscarriedoninthesamelarge-sizesystemfacilityof

100haEveniftheseprocessesrepresentthetargetprocessesfortheauthors,ithastobe

saidthatabasecaseofthemhasbeenanalyzedaswellbytheauthorsthemselves.Butas

thepurposeofthisthesisistoshowanoptimizedversionofthecurrentprocesses,we

assumedaswellthattheirtargetprocessesareouroptimizedones.

Thefacilityisalreadydesignedasawellenhancedone,consideringatleastthestructure

facility,butmanyassumptionshavebeentakenfordevelopingit:

• Highproductivityyields;

64

• Co-locationwithawasteCO2stream;

• Gravityenhancedvolumetransfers;

• Airliftpondcirculation;

• Efficientconversion/extractionmode;

• Renewableenergy;

• Lifetime:30years;

Intheoriginalworkthefunctionalunitis1hasotheirdatahavebeenadaptedtothe

functionalunitofthethesisthatis1MJ.BesidesthefacilitytakesplaceintheUSorinthe

Hawaii,whileforbeingconsistentwiththepreviousprocessinvestigatedinchapter6.1,we

stillassumethatourfacilitytakesplaceinthecenterofItaly,andaccordingtothatthesame

transportdistancesareconsidered(i.e.transportofthefinishedfuelfromItalyto

Switzerlandbytrain,andregionaldistributionperformedwithtrainsandlorries).

Thefuelproductioninthepaperisassumedasacoproduct,andwiththeOpenalgaeprocess

isalsoconsideredaco-productionofanimalfeed,replacedwithtwoprocessesavailablein

theecoinventdatabase:soybeanmealandcornmaze.

6.1.1WetSolventExtraction

Thisprocessaccordingto(Bealetal.,2015)isbasedonthecurrenttechnologiesfor

harvestingandprocessingthebiomassproduced(e.g.paddlewheelforcirculatingthe

biomasscontinuously,theuseofacentrifugeforconcentratingitortheuseofaringdryier

fordryingthealgae),evenifitisknownthatarenotefficient.Thepondhastobemixedin

thiscasefor24h.ThealgaestrainconsideredisStaurosirasp.withproductivity,asmentionedabove,of19g/m

2/dandanoilyieldof0.31kgoil/kgdryalgaebiomass.

Beforeprocessingthealgaeproducedtheymustbethickenedtoasolutionof90%solids.

Thisisperformedthroughthecentrifugationstepandtheringdrier.Aftertheseoperations

thealgaearereadytobeprocessed,inordertoextracttheiroilcontent.Adirectsolvent

extractionusinghexaneassolventisused.Throughthisextractionprocessthe50%oflipids

containedintothealgaeiscollectedasabiocrude.Forcalculatingthisqiuantitywecanrefer

tothefollowingequation:

2 ∙ 34 ∙ 55 = 0.155 ∙ 2 = 89

Where:

• M:totalmassoutput[Mton/day]

• Lc:Lipidcontent=0.31

• RR:recoveryrate=0.5

• Br:Biocruderecovered[Mton/day]

65

Accordingto(Bealetal.,2015)intheoperation1%ofthesolventislostand0.005gof

phosphoricacidisneededpergofbiocruderecovered.Thebiomassthatremainsafterthe

oilrecoveryisallconsideredasanimalfeed.

Respecttotheoriginalpaperweconsidertwosourceofelectricitytopowerthedifferent

operations:theSwissaveragemix,inordertohavethesamecomparisonmixwiththeother

processesinvestigatedthroughthethesis,andtheItalianaverageone,asitisassumedthat

thecultivationwilltakeplaceabroadfromSwitzerland,preciselyinthecenterofItaly.

Thisprocessconstitutesforusaswellasourbasecase.

Anothermodificationprovidedtotheoriginalpaperisthattheanimalfeedco-productsare

energyallocatedconsideringthebio-crudeproduced:

Co-products LHV[MJ/kg] EnergyAllocationGasoline 44.4 0.34

Soybeanmeal 19.7 0.50

Corngrain 18.7 0.16

Table25:Gasolineenergyallocationdirectsolventextractionprocess

Thefuelthatwearegoingtoconsiderisgasoline,becauseinthepaperitisassumedthat

thisfuelisreplacedasitsproductionisavoided.

TheLCIofthisbasecaseprocessisshownbeneathconsideringaselectricitytheItalian

averageone,butintheresultssectionalsotheSwissaveragemixisgoingtobeshowed:

Products Base Unit Comment

GasolineSolventExtraction 1 MJ Isbasedonthe

productionof0.025

kgofgasoline

Resources

Occupation,waterbodies,artificial 0.287 m2a

Occupation,industrialarea 0.0546 m2a

Materials/fuels

Ammonia,liquid|ammoniaproduction,steamreforming,liquid|

AllocRec,U

0.00317 kg Fertilizer

Phosphatefertiliser,asP2O5(GLO)|marketfor|AllocRec,U 0.000237 kg Fertilizer

Packagingfilm,lowdensitypolyethylene(GLO)|marketfor|Alloc

Rec,U

0.01396 kg Infrastructure

Polyvinylchloride,bulkpolymerised(Morero,Groppelli,&

Campanella)|polyvinylchlorideproduction,bulkpolymerisation|

AllocRec,U

4.98E-06 kg Infrastructure

Transport,lorry20-28t,fleetaverage/CHU 2.25E-

5*150

tkm Regional

distribution

Hexane(GLO)|marketfor|AllocRec,U 0.000374 kg Solvent

Phosphoricacid,fertilisergrade,withoutwater,in70%solution

state(GLO)|marketfor|AllocDef,U

4.63E-05 kg Compoundneeded

intheoilextraction

Transport,freighttrain(CH)|electricity|AllocRec,U 2.25E-

5*100

tkm Regional

distribution

Transport,freighttrain(IT)|processing|AllocRec,U 2.25E-

5*960

tkm TransportfromItaly

bytrain

66

Electricity/heat

Electricity,lowvoltage,atgrid/ITU 0.255 kWh Totalelectricity

requiredperMJof

gasolineproduced

Heat,naturalgas,atboilermodulating>100kW/RERU 0.5437 MJ Totalheatrequired

fortheproduction

of1MJofgasoline

Emissionstoair

Hexane 0.000374 kg Solventloss

Finalwasteflows

Polyethylenewaste 0.01396 kg Disposalof

infrastructure

Polyvinylchloridewaste 4.98E-06 kg Disposalof

infrastructure

Table26:Hexanesolventextractionprocess-LCI

6.2.2HydrothermalLiquefactionprocess(HTL)OptimizedCase-LCI

Oneoftheprocessescarriedoutinthestudyof(Bealetal.,2015)istheHydrothermal

Liquefactionprocess,anditisbasedontheonedevelopedatPacificNorthwestNationalLab

(PNNL)(Zhu,Albrecht,Elliott,Hallen,&Jones,2013).Thehydrothermalprocessingisan

approachusedforexploitingthehighmoisturecontentofthealgae,asittakesplaceusing

wateratelevatedtemperaturesandpressures,andwithintheseconditionsthealgaecells

willbreakdowntoformbio-oilandgases(Brownetal.,2010).Thisprocessrepresenta

targetcasealreadyintheoriginalpaper,thusweconsideritouroptimizedcase,including

thenalltheassumptionsexposedinchapter6.

Thedesignofthefacilityhasnotchangedforthiscase,butinrespecttothebaseline

processanalyzedinthesub-chapter6.2.1thealgaestrainusedisDesmodemussp.withabiomassproductivityof23g/m

2/dayandanoilyieldof0.38kgoil/kgdryalgaebiomass.

Furthermoretheprocessesusedforprocessingthealgaeareconsideredmoreeffective

thantheonesseenbefore(e.g.airliftpondcirculationinsteadofthepaddlewheels,filter

pressinsteadofthecentrifugation).Thecirculationtimeoftheopenpondsisnowreduced

to12hfromthe24hofthebasecase.Theelectricitytobeusedshouldberenewableand

comingfromawindpowerplant,butforbeingconsistentwiththeotheroptimized

processesofthethesistheelectricitywillbeagainthelowvoltagehydropoweronecreated

fortheThelmaproject(StefanHirschberg,2016).

ThetransportsbyroadfortheregionaldistributionofthefinishedfuelinSwitzerland,

comparedtothebasecaseprocessareprovidedbyaEURO6lorry.Thereductionofthe

atmosphericemissionsby50%ishereaswelldone,andisbasedonthebasecaseofthe

sameprocess,evenifwearenotgoingtoshowthedataconcerningit.

Toperformthisprocessintheoriginalpaperisassumedthattheheatandtheelectricity

67

requiredareprovidedbyanonsitecombinedheatandpowerplant(CHP).Thelipidrecovery

fromthebiomassisassumedtobethe50%ofallthebiomassproducedandisconverted

intobiocrude.Wecannowexpressthebiocruderecoveryinthisway:

2 ∙ 55 = 89

Where:




Thiswayofassumingthelipidrecoveryisbasedontheassumptionsmadeintheoriginal

paperby(Bealetal.,2015),andwearesimplyagreeingwiththeirassumptions.

Thisprocessdoesnotconsideranyco-production,butconsidersonlytheproductionof

gasolinestartingfromalgae,thusnoenergyallocationhasbeenusedinit.Furthermorethe

emissionsoftheCHPplantarepartoftheLCIof(Bealetal.,2015).

HereaftertheLCIoftheprocessispresented:

Products Optimized Unit CommentGasoline_HTLOptimized 1 MJ Isbasedonthe

productionof

0.025kgof

gasoline

Resources



Materials/fuels

Ammonia,liquid(Moreroetal.)|ammoniaproduction,steam

reforming,liquid|AllocRec,U

0.00546 kg Fertilizer

Phosphatefertiliser,asP2O5(Moreroetal.)|diammoniumphosphate

production|AllocRec,U

1.82E-05 kg Fertilizer

Packagingfilm,lowdensitypolyethylene(GLO)|marketfor|AllocRec,

U

0.001255 kg Infrastructure

Polyvinylchloride,bulkpolymerised(GLO)|marketfor|AllocRec,U 4.49E-06 kg Infrastructure

Transport,freight,lorry16-32metricton,EURO6(GLO)|marketfor|

AllocRec,U

2.25E-5*150 tkm Regional

distribution

Transport,freighttrain(CH)|electricity|AllocRec,U 2.25E-5*100 tkm Regional

distribution

Transport,freighttrain(IT)|processing|AllocRec,U 2.25E-5*960 tkm Transportby

trainfromIT

toCH

Electricity/heat

Electricity,lowvoltage,hydropower,2030+,atgrid/CHU 0.0237 kWh Overall

electricity

requiredper

MJproduced

Heat,naturalgas,atboilermodulating>100kW/RERU 0.0168 MJ Overallheat

requiredper

MJproduced

Emissionstoair

68

Nitrogenoxides 1.379E-6*0.5 kg CHP

emissions

Carbonmonoxide,biogenic 4.41-6*0.5 kg CHP

emissions

Methane,biogenic 2.117E-6*0.5 kg CHP

emissions

NMVOC 1.748E-7*0.5 kg CHP

emissions

Sulfurdioxide 1.763E-6*0.5 kg CHP

emissions

Dinitrogenmonoxide 12.33E-7*0.5 kg CHP

emissions

Finalwasteflows

Polyethylenewaste 0.001255 kg Infrastructure

Disposal

Polyvinylchloridewaste 4.49E-06 kg Infrastructure

Disposal

Table27:GasolinefromHTLprocess-LCI

6.2.3OpenAlgaeProcess(WetExtraction)Optimized-LCI

Thisprocessisequaltothepreviousoneanalyzedinsub-chapter6.2.2,anddiffersfromit

onlybecauseoftheoilextractionmethodused.Themethodnowusedisawetextraction

methoddevelopedby(H.Thomas,2014)namedOpenalgae.

Theprocessisbasedon4mainsteps:growofthealgae,concentration,separationandoil

recover.Theoilrecoveredisthenupgradedaccordingto(Bealetal.,2015)intogasoline,as

itisaco-productoftheprocess.

TheOpenalgaeprocessshouldallowforlessenergyconsumptionbecausetheseparation

stageiseffectedusingelectro-magneticforcestobreakdownthecells.Aftertherecoveryof

theoil,theremainingbiomasscanbeusedasapossibleanimalfeedstock,withanextra

addedvaluebecauserichinOmega-3,soeconomicallyvaluable.

Also,thewaterusedforcultivation,canbecleanedaftertheoilrecoveryandsentbackto

thecultivationstep.

Consideringthat,asinthefirstprocessinvestigatedinsub-chapter6.2.1,thereareco-

productsoutoftheprocess(i.e.animalfeedsubstitutedbythesoybeanmealandcorngrain

processesfromtheecoinventdatabase),againanenergyallocationisperformedasitis

shownbelow:

Co-products LHV[MJ/kg] EnergyAllocationGasoline 44.4 0.49

Soybeanmeal 19.7 0.39

Corngrain 18.7 0.12

Table28:EnergyallocationOpenalgaeprocess

ThevaluesshowedinTable27differfromthoseoftable24becausethebiomass

productivityandtheoilyieldnowconsideredaredifferent.Thisisbecausethealgaestrain

nowusedisDesmodemussp.withabiomassproductivityof23g/m2/dandanoilyieldequal

to0.38kgoil/kgdryalgaebiomass.Themaindifferencethough,apartfromthehigher

69

biomassproductivity,istherecoveryratethatispossibletoachievewiththeOpenalgae

process,thatisequalto75%,asitisshownbelowinthefollowingequation:

2 ∙ 34 ∙ 55 = 0.285 ∙ 2 = 89

Where:


• Lc:Lipidcontent=0.38



Inthepaperof(Bealetal.,2015)whatremainsaftertheoilrecoveryisallconsideredtobe

biomassusedasanimalfeed.Anotherdifferencewiththedirectsolventextractionprocess

seeninsub-chapter6.2.1isthatthesolventusedisheptane,andnothexane,asassumedby

theauthors.

Againasforthepreviousprocessinvestigated,thetargetprocessofthepaperof(Bealetal.,

2015)isouroptimizedone.

TheLCIofthegasolineproducedwiththeOpenalgaeprocess,consideringtheenergy

allocation,isshownbelow:

Products Optimized Unit Comment

GasolineOpenalgaeProcessOptimized 1 MJ Isbased

onthe

production

of0.025kg

ofgasoline

Resources



Materials/fuels

Ammonia,liquid(Moreroetal.)|ammoniaproduction,steam


0.00268 kg

Phosphatefertiliser,asP2O5(Moreroetal.)|diammoniumphosphate

production|AllocRec,U

0.0002 kg

Packagingfilm,lowdensitypolyethylene(Moreroetal.)|production|

AllocRec,U

0.001081 kg

Polyvinylchloride,bulkpolymerised(Moreroetal.)|polyvinylchloride

production,bulkpolymerisation|AllocRec,U

3.86E-06 kg

Transport,freight,lorry16-32metricton,EURO6(Moreroetal.)|

transport,freight,lorry16-32metricton,EURO6|AllocRec,U

2.25E-5*150 tkm

Heptane(GLO)|marketfor|AllocRec,U 8.36E-07 kg

Transport,freighttrain(CH)|electricity|AllocRec,U 2.25E-5*100 tkm

Transport,freighttrain(IT)|processing|AllocRec,U 2.25E-5*960 tkm

Electricity/heat

Electricity,lowvoltage,hydropower,2030+,atgrid/CHU 0.0298 kWh

Heat,naturalgas,atindustrialfurnace>100kW/RERS 0.0117 MJ

Emissionstoair

Heptane

70

Finalwasteflows

Polyethylenewaste 0.001081 kg

Polyvinylchloridewaste 3.86E-06 kg

Table29:GasolinefromOpenalgaeprocess-LCI

6.2.4GasolineProcessesComparison

Astheprocessesanalyzedinthesubchapters6.2.1-6.2.3arebasicallymodelledinthesame

largescalefacility,ithasbeenthoughtthatcouldbeinterestingtothereadertoshowthe

LCIsofthethreeofthemalltogether,sothatispossibletoassistthedifferencesamong

them:

Products Base Optimized-HTL

Optimized–OpenalgaeProc.

Unit Comment

Gasoline_HTLOptimized 1 1 1 MJ Isbasedonthe

productionof

0.025kgof

gasoline

Resources

Occupation,waterbodies,artificial 0.287 0.00583 0.00502 m2a

Occupation,industrialarea 0.0546 0.00111 0.00095 m2a

Materials/fuels

Ammonia,liquid|ammoniaproduction,steam


0.00317 0.00546 0.00268 kg Fertilizer

Phosphatefertiliser,asP2O5|diammonium

phosphateproduction|AllocRec,U

0.000237 1.82E-05 0.0002 kg Fertilizer

Packagingfilm,lowdensitypolyethylene

(GLO)|marketfor|AllocRec,U

0.01396 0.001255 0.001081 kg Infrastructure

Polyvinylchloride,bulkpolymerised(GLO)|


4.98E-06 4.49E-06 3.86E-06 kg Infrastructure


EURO6(GLO)|marketfor|AllocRec,U

2.25E-5*150 2.25E-5*150 2.25E-5*150 tkm Regional

distribution

Hexane 0.000374 0 0 Kg Solvent

Heptane 0 0 8.36E-07 kg Solvent

PhosphoricAcid 4.63E-05 0 0 kg Compound

neededfor

biocrude

recovery

Transport,freighttrain(CH)|electricity|Alloc

Rec,U

2.25E-5*100 2.25E-5*100 2.25E-5*960 tkm Regional

distribution

Transport,freighttrain(IT)|processing|Alloc

Rec,U

2.25E-5*960 2.25E-5*960 2.25E-5*100 tkm Transportby

trainfromIT

toCH

Electricity/heat

Electricity,lowvoltage,hydropower,2030+,

atgrid/CHU

0.255 0.0237 0.0298 kWh Overall

electricity

requiredper

MJproduced

71

Heat,naturalgas,atboilermodulating

>100kW/RERU

0.5437 0.0168 0.0117 MJ Overallheat

requiredper

MJproduced

Emissionstoair

Hexane 0.000374 0 0 Kg SolventLoss

Heptane 0 0 8.36E-07 kg SolventLoss

Nitrogenoxides 0 1.379E-

6*0.5

0 kg CHP

emissions

Carbonmonoxide,biogenic 0 4.41-6*0.5 0 kg CHP

emissions

Methane,biogenic 0 2.117E-

6*0.5

0 kg CHP

emissions

NMVOC 0 1.748E-

7*0.5

0 kg CHP

emissions

Sulfurdioxide 0 1.763E-

6*0.5

0 kg CHP

emissions

Dinitrogenmonoxide 0 12.33E-

7*0.5

0 kg CHP

emissions

Finalwasteflows

Polyethylenewaste 0.01396 0.001255 0.001081 kg Infrastructure

Disposal

Polyvinylchloridewaste 4.98E-06 4.49E-06 3.86E-06 kg Infrastructure

Disposal

Table30:Gasolinefromalgaeprocessescomparison-LCI

72

7. LifeCycleImpactAssessment&Results

Startingfromaspecifictypeofbiomass(i.e.wood,manureandalgae)thedifferentbiofuels

willbecomparedinpoweringdifferentcarscoveringonekilometer.Beforedoingthatthe

quantifiedresultper1MJoffuelwillbeshowedtothereader.

Thisisveryimportantbecauseinthiswayitispossibletoshowwhatisinfluencingdirectly

thedifferentimpactcategories.

Amongtheimpactcategoriesthathavebeeninvestigatedonlyfourmid-pointindicatorswill

beshowninthischapter,becauseareconsideredthemosteffectiveindisplayingtheresults

tothereader.Alltheotherresultsaregoingtobeshowninanappendixsectionattheend

ofthethesis.

Themid-pointschosenforthissectionarethoseexplainedinthesubchapter3.4:

• Globalwarmingpotential[kgCO2eq.];

• Freshwatereutrophicationpotential[kgPeq.];

• ParticulateMatterFormationpotential[kgPM10eq.];

• NaturalLandTransformationpotential[m2];

ThedataforallthevehicleshavebeentakenfromtheThelmaproject(StefanHirschberg,

2016),andtheirenvironmentalimpactshavebeendividedinthesecategories:

• Car:consideringfortheproduction,themaintenanceandthedisposalofthecar;

• Road:impactsontheenvironmentduetoproductionandmaintenanceoftheroad;

• Fuel/Electricitysupply:everycarispoweredbyacertainamountofenergy(MJ/km),

whichissuppliedbythedifferenttypesofbiofuelsinvestigatedandthencompared

withfossilfuels,conventionalbiofuels(e.g.soybeanester),differentelectricitymix,

andhydrogenproducedfromfossilsources;

• Emissions:theyincludethefueldependentemissions,theregulatedemissions,and

thenon-exhaustemissions.Thedifferencebetweenacarpoweredwithafossilfuel

andonepoweredbyabiofuelisthattheemissionsforthelasthavebeenconsidered

biogenic.Alltheotheremissionsfromcombustionoffossilfuelsbyvehicleshave

beenassumedtobethesameforcombustionofbiofuels.

73

Theamountofenergyusedbythesedifferentcarsforcoveringonekilometeris:

Vehicle EnergyUsed[MJ/km]ICEVgasoline 2.7

ICEVdiesel 2.4

ICEVCNG 2.8

BEV 0.9

FCEV 1.6

Table31:CarsPower

Tocalculatetheemissionsduetoburningbiofuels,theywereassumedtobethesameas

thosefromburningfossilfuelsinthesamecar,withtheexceptionofbiogenicCO2,COand

CH4.ThisdatacamefromprojectTHELMA(StefanHirschberg,2016).

74

7.1WoodPathways

7.1.1GlobalWarmingPotential

Thebiofuelsproducedwithdifferentpathwaysfromthewoodbiomassareherecompared.

Inthefollowingcharttheresultsofproducing1MJoffuelaredisplayed.Doingthatitis

possibletoassesswhicharethemaincontributorsinthedifferentcategories.Itwillalsobe

possibletoseethedirectcomparisonbetweenthecurrentcasesandtheoptimizedones.

Thecategoriesexaminedinthefollowingchartare:

• Directemissions:emissionsstrictlyrelatedtotheproductionofthefuel;

• Materialinputs:alltheinputsrequiredforproducingthebiofuelliketheraw

biomass,theprocessingwater,ortheoperationalmaterials(e.g.silicasandforthe

fluidizedbedreactors,orcompoundusedforcleaningtherawbiogasproduced);

• Infrastructure:theplants,orthecomponentsneededforprocessingthebiomass;

• Transport:thelorriesorthetrainsusedforcarryingtherawbiomassorthefinished

fuel;

• Catalyst:isanoperationalinputbutasitusuallyhavebiginfluenceonmostofthe

impactcategoriesweprefertoshowitseparately;

• Electricity;

• Heat;

• Waste:includesallthewastesattheendoftheprocesses,andcanincludethe

wastewatertreatment,orthedisposalofusedminerals,orinertmaterialsorashes;

75

Chart1:WoodpathwaysGWPresultsperMJ

Asitpossibletoseethegasificationpathwayissofarthelesscontributingone.Eventhe

conversionintoelectricityofthewoodchipsthroughacogenerationplantrepresentsavery

goodsolution.Fortheotherprocessesexamined,wecanassesshowinthecasesofthe

conversionofwoodchipsthroughthefastpyrolysisstepintogasolineordieselthemain

contributioncomesfromthedirectemissionsoftheprocess.Inthecaseofhydrogen

productioninsteadfromthematerialinputs,whicharerepresentedmainlybythehydrogen

producedstartingfromthegasificationofthebiomass.

Consideringthefastpyrolysis,themaincontributoristhebio-crudeproducedduringthe

upstreamprocesswherethecombustionofnaturalgasintheprocessaffectsbadlythis

category,plusthetransportsfreightusedforthedifferentoperations(i.e.collectingthe

biomass,transportingthefinishedfuel).Inconsideringtherawbiomass,thechopping

operationsarethemostcontributingtotheclimatechangebecauseofthemachinesused

thatconsumedieselfuel.

Consideringinsteadthecomparisonsofthedifferentfuelsproducedwiththedirect

alternatives,wearegoingtoshowtheresultsobtainedinpoweringthedifferentcarsper

onevehiclekilometer.

0

0,01

0,02

0,03

0,04

0,05

0,06

0,07

0,08

0,09

Base Optim. Base Optim. Base Optim. Base Optim. Base Optim. Base Optim.

WFP WFP Gasif. HTG Cogen Gasif.

Gasoline Diesel Methane Electricity Hydrogen

kgCO2eq

.PerM

JGWP

DirectEmiss. MaterialInputs Infrastructure Transport

Catalyst Electricity Heat Waste

76

Chart2:WoodpathwaysGWPresultspervkm

Afirstimportantresultcomingfromthischartisthat,consideringtheGlobalWarming

Potential,thebestwaytoexploitwoodbiomassforpoweringavehicleismainlytogasifyit

andthenupgradetheSNGproducedintomethane.

AlsoconsideringtheSwissaverageelectricitymix,burningthewoodintoacogeneration

plantmayrepresentagoodwayforusingthisbiomassfeedstocktopoweracar.

Someotherconsiderationsthougharisefromthischart.OneofthemisthatthePyrolysis

processisnotthemosteffectivewaytoexploitthebiomassforproducingafuel,atleastnot

nowadays;GWPimpactsaresimilartousingfossilfuels.Improvementsofthistechnologyin

thefuturethough,mayleadtomoreinterestingresults.

Anotherconsiderationcomingoutfromthischartisthathydrogenproducedstartingfrom

woodybiomassrepresentsapromisingpathwayforproducingit,ascomparedwiththe

fossilwaytodoitisalreadycompetitiveandmightbecomemuchbetterwiththe

improvementssupposedbythiswork.

7.1.2FreshWaterEutrophicationPotential

Thefollowingchartisabouttheimpactresultinginthisspecificcategoryfromthe

productionof1MJoffuels,inthedifferentpathways.

0

0,05

0,1

0,15

0,2

0,25

0,3

0,35

0,4

Base

Optimized

Base

Optimized

Base

Optimized

Base

Optimized

Base

Optimized

Base

Optimized

Base

Optimized

WFP Fossil WFP Fossil Gasif. HTG Fossil ORC Cogen CH CoalHydro Gasif. SMR


kgCO2eq

.pervkm

GWPCAR ROAD FUEL/ELECTRICITYSUPPLY EMISSIONS

77

Chart3:WoodpathwaysFreshwatereutrophicationresultsperMJ

AstheinthechartseenintheGWPcategoryonceagainthefuelsproducedfromthefast

pyrolysisprocesstogetherwiththehydrogenproducedfromthebiomassgasification

processarethoseperformingpoorly.Althoughinthiscasethemajorcontributionscome

fromthecatalystsusedandthematerialinputs.

Thecatalysthassuchabigcontributionbecauseoftheminingoperationinvolvedinthe

productionofoneofitscomponenttheMolybdenum.

Consideringinsteadthehydrogenprocesswhatisaffectingthiscategoryistheelectricity

requiredforitsproductionandcompressionto700bars.Thereasontothatisthe

combustionofligniteforproducingtheelectricity,andthedisposalofthespoilfromlignite

miningarehighlyinfluencingthiscategory.Theminingspoilsincludemanyhazardous

compoundsemittedtothewater,wherethemainonesintermsofquantityareforexample

amongtheothers:Sulfate,Silicon,Potassium,MagnesiumandSodium.

0

0,00001

0,00002

0,00003

0,00004

0,00005

0,00006

Base Opt. Base Opt. Base Opt. Base Optim. Base Opt. Base Opt.



kgPeq.perM

JFreshwaterEutrophication



78

Chart4:WoodpathwaysFreshwatereutrophicationresultspervkm

Evenfromthethischartthatassessestheimpactsofthedifferentfuelspervkmthe

pyrolysisprocessandthehydrogenproductionarethosethatperformpoorly.

Nevertheless,theotherpathwaysexploredshowsgoodperformancesinthisimpact

category,andtheircontributionisnotthatmuchifcomparedwiththeroadandcar

categories.Soasstatedfortheglobalwarmingpotentialcategorytheconversionofthe

woodbiomassintomethaneorintoelectricityareagainthebestwaysforexploitingthis

source.

7.1.3ParticulateMatterFormationPotential

Wearegoingnowtoshowtheresultsforthisparticularmid-pointindicatorthatisausual

oneusedwhenassessingtheenvironmentalimpactsoftransportationunits.

Wewillshowfirstthechartindicatingtheimpactoftheproductionof1MJoffuels,soitwill

bepossibletoassessinthespecificwhatisreallycontributinginthisimpactcategory.

0,00E+00

2,00E-05

4,00E-05

6,00E-05

8,00E-05

1,00E-04

1,20E-04

1,40E-04

1,60E-04

1,80E-04

2,00E-04

BaseOptim. BaseOptim. BaseOptim.BaseOptim. BaseOptim. BaseOptim.

WFP Fossil WFP Fossil Gasif. HTG Fossil Cogen CH Coal Hydro Gasif. SMR


kgPeq.pervkm

FreshwaterEutrophication

CAR ROAD FUEL/ELECTRICITYSUPPLY EMISSIONS

79

Chart5:WoodpathwaysParticulateMatterFormationresultsperMJ

Ineverypathwayispossibletoassesshowthematerialinputsarethemostimportant

contribution.Fortheelectricityproducedinthecogenerationplantthisisindirectlyseeable

becauseaconversionfromhightolowvoltagehasbeenperformed.

Thisisbecauseoftheprocessingofthewoodchips(e.g.harvestingandchippingoperations)

andtheirtransporttotheplant.Andtheirinfluenceisveryimportantandpresentinevery

process,astheyconstitutethestartingbiomass.

Onlyforthehydrogenprocesswecanattributetheresultsobtainedtootherfactors:

• thesyngasproducedfromthebiomassgasification,becauseofthemagnesiumused

asbedmaterialinthegasificationprocess;

• thesteamusedinthesteamreformingprocess,toenhancethehydrogenyield;

• Thechemicalplantandthedistributioninfrastructuresincludedintheprocess;

• Theelectricityusedforprocessingandcompressingthehydrogento700bar;

Afterhavingevaluatedwhicharethemaincontributorsinthisimpactcategory,weare

goingtoshowinthefollowingcharttheimpactsrelatedtotheuseofthesefuelsfor

poweringdifferentvehiclesperavkm.Likeintheothercasesthebiofuelsinvestigatedwill

bedirectlycomparedwiththeirdirectalternatives.

0

0,00002

0,00004

0,00006

0,00008

0,0001

0,00012

0,00014

0,00016




kgPM10eq.perM

JParticulateMatterFormation



80

Chart6:WoodpathwaysParticulateMatterFormationresultspervkm

Regardingthismid-pointcategory,thebiofuelscomparedtotheconventionalfuelsdon’t

performmuchbetter,butstillfacethesameissuesthatarepresentwhenisnecessaryto

burnasubstancetoexploititsenergycontent.

Thetwoprocessesthatshowaslightlyworstperformanceifcomparedwiththeir

counterpartsarethebaselinecaseofthecogenerationplantandthehydrogenproduced

startingfromthegasificationofthebiomass.

7.1.4NaturalLandTransformationPotential

Thelastcategorywearegoingtoshowregardingthewoodpathwaysisthenaturalland

transformationone.Itassesseshowthebiofuelproductionisresponsibleinchangingthe

pre-existentecosystemandenvironment.

Firstly,thechartshowingtheresultsfortheproductionof1MJwillbedisplayed,asitwas

doneinthepreviousessub-chapters.

0,00E+00

1,00E-04

2,00E-04

3,00E-04

4,00E-04

5,00E-04

6,00E-04

BaseOptim. BaseOptim. BaseOptim.BaseOptim. BaseOptim. BaseOptim.



kgPM10eq.pervkm

ParticulateMatterFormation

CARPRODUCTION&DISPOSAL&MAINTENANCE ROAD FUEL/ELECTRICITYSUPPLY EMISSIONS

81

Chart7:WoodpathwaysNaturalLandtransformationresultsperMJ

Asitwaspossibletoexpect,likeintheothercategories,thematerialinputs,sothe

operationsforprocessingthewoodchipsusedinthedifferentpathwaysarethemain

contributorstothisimpact.Asexplainedbeforeforthecogenerationprocess,thisis

indirectlyseeablefromthischart,asitactuallyshowstheconversionfromhightolow

voltageoftheelectricityproduced.

Hereafterinstead,thechartshowingtheresultsforthiscategoryofthedifferentfuels

coveringonevkmispresented:

0

0,000002

0,000004

0,000006

0,000008

0,00001

0,000012




m2pe

rMJ

NaturalLandTransformationDirectEmiss. MaterialInputs Infrastructure Transport


82

Chart8:WoodpathwaysNaturalLandTransformationresultspervkm

Forthisimpactcategoryitispossibletoassesshowthebiofuelsproducedhavealways

higherperformancescomparedtothefossilfuels.

Thefossilfuelsperformpoorlyinthisspecificcategorytheextractionoperationsofthe

petrolorofthenaturalgasfromtheunderground,highlymodifytheoriginalenvironment

andecosystem.

0,00E+00

2,00E-05

4,00E-05

6,00E-05

8,00E-05

1,00E-04

1,20E-04

Base Ideal Base Ideal Base Ideal Base Ideal Base Ideal Base Ideal



m2pe

rvkm

NaturalLandTransformation


83

7.2ManurePathwaysThesameconsiderationsmadeatthestartofchapter7.1areherestillvalid,whatdiffers

nowisthesourceofbiomassexamined,whichisthemanureproducedinSwitzerland.

Thebiofuelsinvestigatedcomefromdifferentprocesses,likethebiomassgasificationand

itssubsequentcleaning,startingfromtheanaerobicdigestionofit.Wehavealsostudied

thehydrothermalgasificationprocess,forproducingmethaneandtheproductionof

electricityfromthecombustionofthemanurebiogas.

Thesebiofuels,arethencomparedwithfossilmethaneorwithelectricitycomingfromthe

Swissaveragemix,theEuropeanone,arenewablesourceofelectricity(i.e.hydropower)or

afossilone(i.e.naturalgas).


Thefirstchartwearegoingtoshowwillexposetheresultsobtainedforproducing1MJof

fuelfrommanurebiomass.

Chart9:ManurepathwaysGWPresultsperMJ

Whatishighlyaffectingthisimpactcategoryarethematerialinputstothedifferent

processes.Tobemorespecificthebiogasusedintheupgradingfacility,forconvertingitto

methane,andtheoneburnedforproducingelectricityinacogenerationplant.Themain

reasontothatisbecauseofthemethaneleakagesfromtheanaerobicaldigestionplant.

Unfortunately,methanehasahugeimpactontheclimatechange,becauseitseffectis25

timesbiggerthantheoneoftheCO2itself.ThatiswhytheHTGprocessperformsmuch

0

0,02

0,04

0,06

0,08

0,1

0,12

0,14

0,16

0,18

0,2

Base Optim. Base Optim. Base Optim.

AnerobicDigestion HTG Cogen.

Methane Electricity

kgCO2eq

.perM

J

GWPDirectEmiss. Infrastructure MaterialInputs Catalyst

Electricity Waste Heat Transport

84

bettercomparedtotheanaerobicdigestionprocessofthemanure,justbecauseavoidsthe

anaerobicdigestionstep.

Thechartrelatedinsteadtotheresultingimpactsofthedifferentprocessesanalyzedin

coveringonevkmwiththedifferentvehiclesisthefollowing:

Chart10:Manurepathways-GWPresultspervkm

Knowingthatthebiogasproductionisheavilyinfluencingthiscategoryispossibletosee

hownowadaysthisconversionprocessperformsmuchworsethanthedirectcounterparts.

Infactonlythereductionofthemethaneleakagesmayleadtheanaerobicaldigestionstep

awaytoexploitthisbiomassasitisstatedbyouroptimizedcaseforproducingmethane.

Consideringtheelectricityproducedinthecogenerationplant,thepoorperformancesare

associatedtothedirectemissionsoftheprocess.

TheHTGprocessinsteadavoidingtheanaerobicdigestionstepavoidstheseleakagesand

showsgreaterresults.

0

0,05

0,1

0,15

0,2

0,25

0,3

0,35


Biogas Biogas HTG Fossil Cogen. Cogen. CH EU Hydro Nat.Gas

Methane Electricity

kgCO2eq

.pervkm

GWP


85

7.2.2FreshwaterEutrophicationPotential

Thechartevaluatingtheimpactresultsfortheproductionof1MJoffuelintheFreshwater

Eutrophicationpotentialishereaftershowed:

Chart11:Manurepathways-FreshwatereutrophicationpotentialresultsperMJ

Fromthischartispossibletoevaluate,whichisthemaincontributorinthiscategory.Once

again,itispossibletoassesshowforthemethaneproducedstartingfromtheanaerobic

digestionofthebiomassthematerialinputsarethemainresponsible.Withthematerial

inputswemeanthebiogasusedintheupgradingplantfromwhichthemethaneisobtained.

Asforthemethanepath,thesameconsiderationscanbemadeforthebiogasburnedfor

producingelectricityinthecogenerationplant.

Thebiogasisseverelyaffectingthiscategoryforthesemanifoldreasons:

• Themanureinputanditstransportation(theseareincludedinthebiogas

production);

• Theanaerobicdigestionplant,becauseofthematerialsusedforitsconstruction

(e.g.copper,reinforcedsteel);

• Theglycerinusedasaco-substrate,asitsproductioncomesfromtheesterification

plantsofsoybeanandrapeoilrespectively;

• Theimportofelectricityfromcountrieswherecoalandligniteareusedforits

production(i.e.theminingdisposalinthespecific),especiallythelignite’smining

operationsarehighlyaffectingthismid-pointindicator;

0

0,02

0,04

0,06

0,08

0,1

0,12

0,14

0,16

0,18

0,2



Methane Electricity

kgCO2eq

.perM

J

FreshwaterEutrophicationDirectEmiss. Infrastructure MaterialInputs Catalyst


86

AgainstthesetwopathwayswecanassesshowtheHTGprocessiseveninthiscategorywell

performing.

Thefollowingchartpresentedwillcomparehowinthisimpactcategory,thedifferentcars

analyzedperform:

Chart12:Manurepathways-Freshwatereutrophicationpotentialresultspervkm

Twoimportantconsiderationscomefromthischart.Thefirstisthatcomparedtofossil

methanetheoneproducedstartingfromthebiomasshasworstperformances.Thisis

mainlyduetothebiogasitselfusedintheupgradingsection,andtothecatalystneededin

theHTGprocess.

Theelectricitypathwayinsteadshowsgoodperformancesinthiscategory,comparedwith

theotherselectricitysources.

Anexplanationonwhytheelectricitypathwayshowsbetterresultsthanthegasification

one,isgivenbytheamountofenergyneededbythedifferentcarsasshowedinTable30.

0,00E+00

2,00E-05

4,00E-05

6,00E-05

8,00E-05

1,00E-04

1,20E-04

1,40E-04

1,60E-04



Methane Electricity

kgPeq.pervkm

FreshwaterEutrophication


87


Thechartpresentingtheimpactsrelatedtotheproductionof1MJoffuelisthefollowing

fortheparticulatematterformationindicator:

Chart13:Manurepathways-PMFresultsperMJ

Asitwasstatedintheprevioussubchapterthematerialinputsareagainthemaindriversin

thisspecificimpactcategory.Tobemorepreciseforthemethaneproducedfromthe

anaerobicdigestionprocessthebiogasisthemainresponsible,asitisintheelectricity

pathway.Thisisduetomanyreasons:

• Themanureanditstransportation

• Theanaerobicdigestionplant

• Theglycerinfromtheesterificationprocessofrapeoil

• Theheatrequiredtomaintainspecificconditionsintheanaerobicdigestionprocess

whosesourceismainlylightfueloil

IntheHTGprocess,theimpactsmainlycomefromthemanureitselfanditstransportation,

asintheothertwoprocesses.

Thechartcomparinginsteadtheresultingimpactsfromthedifferentcarsistheonebelow:

0

0,00002

0,00004

0,00006

0,00008

0,0001

0,00012

0,00014

0,00016

0,00018

Base Optimized Base Optim. Base Optimized


Methane Electricity

kgPM10eq.perM

J

ParticulateMatterFormation

DirectEmiss. Infrastructure MaterialInputs Catalyst


88

Chart14:Manurepathways-PMFresultspervkm

Regardingthiscategoryallthebiofuelsperformbadlyifcomparedwiththefossilalternative

ortheelectricitymixcompared.


Alsoforthiscategoryfirstlywewillshowthespecificcontributorsforthismid-point

indicatorinproducing1MJoffuel:

0,00E+00

5,00E-05

1,00E-04

1,50E-04

2,00E-04

2,50E-04

3,00E-04

3,50E-04



Methane Electricity

kgPM10eq

.pervkm

ParticulateMatterFormationCAR ROAD FUEL/ELECTRICITYSUPPLY EMISSIONS

0

0,000005

0,00001

0,000015

0,00002

0,000025

0,00003

0,000035

0,00004


Biogas HTG Cogen.

Methane Electricity

m2pe

rMJ

NaturalLandTransformationDirectEmiss. Infrastructure MaterialInputs Catalyst


89

Chart15:ManurePathways-NaturalLandTransformationResultsperMJ

Asintheothercharts,whenassessingwhichisthemaindriver,thebiggestcontributionin

producing1MJoffuel,comesfromthematerialinputs(i.e.thebiogasforthemethaneand

electricitypathways,themanurefortheHTGprocess).

Consideringinsteadthedifferentcarswhencoveringonevehiclekilometerthisisthe

resultingchart:

RegardingthecurrentprocessesonlytheHTGprocessshowsagoodperformance

consideringthisimpactcategory.Theupgradingofthebiogasprocessshowsevengreater

performanceswhentheprocessitselfisoptimizedasassumedinchapter5.Finally

consideringthismid-pointindicatortheelectricityproducedwiththeco-generativeengine

doesnotdisplayanyimprovementseveninthefuture.

Inthiscategorybiofuelsarefoundtohavesimilarimpactsifcomparedwiththefossil

alternativesorwiththedifferentelectricitymixconsidered,anddonotseemtopresentan

advantage.

0,00E+00

1,00E-05

2,00E-05

3,00E-05

4,00E-05

5,00E-05

6,00E-05



Methane Electricity

m2pe

rvkm



90

7.3AlgaePathwaysFinally,istheturnoftheAlgaeproductionandexploitationformakingbiofuels.Asstated

beforeinthepreviouschaptersthistechnologyisnotmaturewiththecurrentknowledges,

forthebiofuelproduction,aswearegoingtoassessinthenextsubchapters.

Thebiofuelsproducedfromalgaearegasolineanddiesel,whicharegoingtobecompared

withtheirfossilalternatives,andwithtwoconventionalbiofuels(i.e.SoybeanMethylEster

andPalmMethylEster).

Wearenowconsideringtwopathwaysforproducingthealgae,theOpenPondsRaceanda

hybridsystemthatincludesPhotoBioReactor(PBR)andOPR,asexplainedbeforeinthe6.2

sub-chapter.


Itisimportanttostartshowingthereaderthemaindriversfortheclimatechangecategory

whenproducing1MJoffuelstartingfromalgaecultivation:

TheOPRbasecaseprocessrevealsthatnowadayswiththecurrentmarkettechnologies,

thisfuelcannotcompetewiththeconventionalfossilorbiofuelsones.Fromthechartis

possibletostatethatthematerialinputsforthebiodieselproducedintheOPRarethemain

responsible.Thisisindirectlytrue,becausethematerialinputsconsideredhereisthebiooil

extractedfromthealgaecultivated.Abigproblemcomingfromthisproductisthehigh-

0

0,1

0,2

0,3

0,4

0,5

0,6

0,7

CH IT Optim. Optim. Base Optim.

HexaneExtract. HTL Openalgae OPR

Gasoline Diesel

kgCO2eq

.perM

J

GWPDirectemiss. MaterialInputs Heat Electricity Transport Infrastructure Waste

91

energydemandrequiredforboththecultivationandtheextractionsteps.Theelectricity

andtheheatrequiredareindeedtoointensive.

Onestatementthoughthatispossibletomake,isthattheusageofanoptimizedfacilityand

acleanersourceofenergy,liketheSwissaverageoneorarenewableoneasexplainedin

thepreviouschapters,alreadyshowhowthepotentialityofthistechnologycanberight

nowveryhighandisstrictlyrelatedtotheprocessesandthetechnologyused.

Thechartshowedbelow,compareinsteadtheimpactsforthiscategorywhenthedifferent

carsareused:

Thesameconsiderationsdoneforthepreviouschapterarealsohereapplied.

7.3.2FreshwaterEutrophicationPotential

Forthefreshwatereutrophicationpotentialwestartshowingthechartthatcomparesthe

differentimpactsduetotheproductionof1MJoffuel.Secondlythechartwherethe

differentcarsarecomparedincoveringonevkmwillfollow:

0

0,2

0,4

0,6

0,8

1

1,2

1,4

1,6

1,8


HexaneExtract. HTL OpenAlgae Fossil OPR Soybean Palm Fossil

Gasoline Diesel

KgCO2eq.pervkm

GWP


92

Chart16:AlgaePathway-FreshwaterEutrophicationResultsper1MJ

Chart17:AlgaePathway-FreshwaterEutrophicationResultspervkm

0

0,00002

0,00004

0,00006

0,00008

0,0001

0,00012

0,00014

0,00016



Gasoline Biodiesel

kgPeq.perM

JFreshwaterEutrophication

Directemiss. MaterialInputs Heat Electricity Transport Infrastructure Waste

0

0,00005

0,0001

0,00015

0,0002

0,00025

0,0003

0,00035

0,0004

0,00045



Gasoline Biodiesel

kgPeq.pervkm

FreshwaterEutrophicationCAR ROAD FUEL/ELECTRICITYSUPPLY EMISSIONS

93

Themainconsiderationregardingthisimpactcategoryisthatthebiggestinfluencecomes

fromtheelectricityusedforprocessingandcultivatingthealgae.Onlyintheoptimized

caseswhenlessenergyisrequiredwecanseethatthistechnologymightrepresentaviable

solutioninreplacingfossilfuels.


Thefirstchartshowedistheonethatassessestheimpactsfromtheproductionof1MJof

fuel:

Chart18:AlgaePathway–ParticulateMatterFormationResultsper1MJ

Asfortheothercategories,theelevatedenergydemandisresponsibleofthepoor

performancesofthebasecasesinvestigated.

Thefollowingchartistheonethatcomparesthedifferentcarspoweredbythedifferent

fuelsinvestigated:

0

0,0001

0,0002

0,0003

0,0004

0,0005

0,0006

0,0007

0,0008

0,0009



Gasoline Biodiesel

kgPM10eq

.perM

J

ParticulateMatterFormationDirectemiss. MaterialInputs Heat Electricity Transport Infrastructure Waste

94

Chart19:AlgaePathway-FreshwaterEutrophicationResultspervkm

Asinthepreviousessubchaptersconcerningthebiofuelsproductionfromalgae,theenergy

requiredisstillthemainenvironmentaldriverintheprocessesthatconsiderthecurrent

availabletechnologies.Theoptimizationofthefacilityandtheenergyreductionmustbe

amongtheactionsthatneedtobeundertaken.


Asintheothersubchapterwherethisspecificmid-pointindicatorisshowed,wewillfirst

presentachartwherewewillcomparetheproductionof1MJperthedifferentfuels,and

secondlywewillshowthecomparisonbetweenthedifferentcarscoveringonevkm.

Whenassessingwhicharethemaincontributorsintheproductionofthefuel,asinthe

othermid-pointindicatorstheenergyrequiredisthemajorone.

0

0,0005

0,001

0,0015

0,002

0,0025



Gasoline Biodiesel

KgPM10eq

pervkm

.ParticulateMatterFormation


95

Chart20:

Chart21:

Whencomparinginsteadthedifferentcarscoveringonevkm,inthiscategorythebiodiesel

comingfromthesoybeanhasahugeimpactbecauseofthecultivationofthesoybeanitself.

0

0,00002

0,00004

0,00006

0,00008

0,0001

0,00012

0,00014


HexaneExtract. HTL OpenAlgae OPR

Gasoline Biodiesel

m2pe

rMJ


Directemiss. MaterialInputs Heat Electricity Transport Infrastructure Waste

0

0,001

0,002

0,003

0,004

0,005

0,006

0,007

0,008

0,009



Gasoline Biodiesel

m2pe

rvkm



96

Thispracticeaffectsheavilytheexistentecosystem.

So,despitethepremiseseventhealgaethataresoenergyintensiveperformbetterin

regardstothisspecificcategory,ifcomparedwiththissourceofbiomass.

97

8.DiscussionInthisfinalchapteracomparisonbetweenthisworkandtheavailableliteraturewillbe

performed.Firstly,acomparisonwithareportmadebyEMPAthatistheSwissFederal

LaboratoriesforMaterialsScienceandTechnology,ondifferentbiofuelsproducedin

Switzerlandwillbedone.ThenacomparisonwiththeresultsobtainedinsomeothersLife

CycleAssessmentsintheavailableliteraturewillbeaccomplished.

8.1 ComparisonwithEMPAStudyOnetableisgoingtobeshownbelowwheretheresultspervkmfromtheEMPAreporton

biofuels(MireilleFaistEmmenegger,2012)arecomparedwiththeresultsobtainedwithin

thiswork.

SomedifferencesthoughincalculatingclimatechangeemissionsintheEMPAreporthave

beenperformed.Thenitrogenemissionshavebeenmodelleddifferentlycomparedtothe

ecoinventv2.2databaseastheyhavebeenharmonizedandupdated,basedonthe

Agrammonmodel(www.agrammon.ch).Also,theemissionsrelatedtothelandusechange

havebeencalculateddifferently,asinecoinventv2.2onlytheemissionsassociatedtothe

cuttingofrainforestareconsideredforthiscategory(MireilleFaistEmmenegger,2012).

Bothnitrogenandlandusechangeemissionsaresignificantcontributorstotheglobal

warmingissue.

EMPA ThisStudy–BaseCase

Biofuel Process GWP[kgCO2eq.pervkm]

GWP[kgCO2eq.pervkm]

Methane,manure HTG 9.2E-02 1.42E-01

Methane,manure Anaerobicdigestionbiogas

- 2.72E-01

Methane,woodchips HTG 7.0E-02 1.10E-01

Methane,woodchips SNGpurification

- 3.30E-02

NaturalGas 2.6E-01 2.28E-01

Diesel 2.7E-01 1.99E-01

Petrol 3.2E-01 2.69E-01

Table32:ResultscomparisonwithEMPAreport

98

Thefirstconsiderationobtainablefromthiscomparativetableisthattheresultsobtainedby

thisstudyarehigherconsideringtheHTGprocesses,whilearelowerconsideringthefossil

fuelsusedforcomparison.

StatingthattheactualdatausedforthecalculationsintheEMPAreportarenotavailable,

someconsiderationsaboutwhichcouldbethepotentialreasonsonwhythereare

differencesintheresultsmustbedone.

Itispossiblethattheinputsandtheassumptionscarriedoninthisthesisaredifferent.For

exampleintheHTGprocessofmanurethesuppositionsof(Luterbacheretal.,2009)have

beencompletelychanged,inordertoharmonizetheresultswiththeotherprocesses,as

explainedinsub-chapter5.3.Anotherdifferenceisthattheanimalslurryusedasinputin

thisthesisisfromtheecoinventv3.01,whiletheoneusedintheEMPAreportisfrom

ecoinventv2.2.

EvenintheHTGprocessofwood,thebiomassinputusedisdifferent,becausewhileinthis

studywoodchipsfromindustrywastewith40%ofhumidityhavebeenutilized,intheEMPA

reportthebiomassinputisconstitutedbyforestryandsawmillswastes.Inthisthesis,the

woodchipsusedarethemaincontributorintheGWPcategory,asithasbeenstatedinsub-

chapter7.1.1.

FurthermorethevehiclesusedintheEMPAreport(MireilleFaistEmmenegger,2012)are

differentfromthoseusedbythiswork,asthedataforthecarsarefromtheTHELMAproject

(StefanHirschberg,2016).TocalculatetheemissionsfactorsofCO2intheEMPAreportthe

Tremovedatabasehasbeenused(T&M-Leuven,2007).

TheEMPAreportstatesthattheenergyconsumptionsofthecarsarethefollowing:

Fuel EnergyDemand[MJ/km]–EMPAreport

EnergyDensity–LHV[MJ/kg]

Gasoline 2.86 42.9

Diesel 1.82 42.8

Methane 2.51 48.6

Table33:EnergyDemandperkm-EMPAreport

Whiletheenergydemandsconsideredforthisthesisare:

Fuel EnergyDemand[MJ/km]–EMPAreport

EnergyDensity–LHV[MJ/kg]

Gasoline 2.8 44.4

Diesel 2.4 42.8

Methane 2.7 34.4

Table34:EnergyDemandperkm-thisthesis

99

LHVsofgasolineanddieselhavebeenchosenlikethoseaccordingtothevalueschosenin

thepaperof(Iribarrenetal.,2012),whiletheenergydensityofmethanewaschosen

accordinglytotheecoinventdatabase.

Asitispossibletostatefromtable31,theresultsobtainedintheGWPcategoryconsidering

anaveragemid-sizedcardrivingakilometer,arealwaysslightlybetterconsideringthis

thesis,evenifthedieselcaroftheEMPAreportconsumeslessenergy.Apossiblereasonis

thattheemissionsstandardsusedintheEMPAreportareEURO3,whilethoseusedinthis

thesisareEURO5,whichallowtheseimprovements.

Allofthesedifferencesmighthaveledtothedisparitiesintheresultsobtained.

8.2 ComparisonwithOtherLCAsonBiofuelsAtablecomparingtheresults(ingCO2eq.pervkm)obtainedinotherLCAsandthosefrom

thisthesiswillbepresentedbelow:

Fuel Source Cherubini(1)

EMPA(2)

Thiswork-BaseCase

Zah(2007)(3)

Weinberg-Kaltschmitt(4)

Diesel Fossil 185-220 260 199 288 -

Gasoline Fossil 210-220 320 269 320 -

NaturalGas

Fossil 155-185 260 228 261 -

Bio-Methane

Manure-HTG - 92 142 - -

Manure-AD - - 272 216 -

WoodGasific. - - 78 94 59

Wood-HTG - 70 110 - -

Hydrogen WoodGasification - - 180 - 132.4

SMR - - 159 - -

Electricity Woodchips-CHP 74 - 75 - 85

Table35:ComparisonwithotherLCAs

(1)(Cherubinietal.,2009);

(2)(MireilleFaistEmmenegger,2012);

(3)(R.Zah,2007);

(4)(Weinberg&Kaltschmitt,2013)

Fromtable34ispossibletomakesomestatementswhencomparingthebiofuelsmodeled

withinthisworkandthosefromotherstudies.

Isnecessarythoughtostatethattheactualdatausedinthedifferentstudiesarenot

available.

Startingthecomparisonbetweenconventionalfossilfuelsusedasreference,itispossibleto

seehowthevaluesobtainedbythiswork,basedontheTHELMAproject(StefanHirschberg,

2016)areusuallylower,andonepossibleexplanationcanbegivenbythefactthatthecars

100

investigatedinthisthesishaveEURO5emissionsstandards,whiletheothershaveEURO3

emissionsstandards.EU

Consideringthemethaneproducedthroughthehydrothermalgasificationprocessthe

considerationsmadeintheprevioussub-chaptersremainthesame,whilethemethane

producedstartingfrommanurebiogashasbiggeremissionscomparedtotheworkof(3).It

ispossiblethatthisisduetotheuseofdifferentecoinventdatabase(i.e.v2.2andv3.01)

respecttothoseusedby(R.Zah,2007)whereecoinventdatabasev1.3wasadopted.While

thevalueregardingmethanefromwoodgasificationisinbetweentheothertwostudies

usedforcomparison.AlsotheelectricityproducedfromaCHPplanthasavalueinbetween

theothertwoworksconsidered.

Theresultsobtainedfortheproductionof1MJofdieselorgasolinefromthefastpyrolysis

processfromthisthesishavenotbeencomparedwiththeoriginalwork,becausethevalues

obtainedfortheGWPcategoryin(Iribarrenetal.,2012)arenegative,astheyconsiderthat

theCO2isremovedfromtheatmospherethankstothegrowingofthebiomass.

InreferencetothealgaeproducedintheOPRandtheupgradeoftheoilextracteda

comparativetablebetweenthisworkandtheoneof(Passelletal.,2013)(5)thatconsiders

thecurrentcommercialtechnologyinabaseandoptimizedcasewillbepresentedbelow.

Fuel Passell(5) ThisWorkBiodiesel BiodieselOPR-

BaseCase

2,88 1,63

BiodieselOPR-

Optimized

0,18 0,04

Table36:BiodieselfromalgaecultivatedinOPRcomparison

AsitisevidentthebiodieselmodeledinthisthesisreachedloweremissionsvalueperMJ

produced,eveniftheinfrastructurehasbeenaddedtotheprocess.Thereasonswhythese

valuesaresodifferentaremanifold,butthemainreasonresidesintheelectricityusedfor

processingthealgae.Intheworkof(5)theelectricityusedistheAmericanaveragemixin

thebasecaseandtheGermanaveragemixintheoptimizedcase.Whileinourbasecase

processtheelectricitymixusedistheItalianone,andintheoptimizedoneistheSwiss

hydropowerelectricitymixthatisthecleanestsourceofenergyimplemented.Ithasbeen

saidthatthisisthemainreasonbecauseaswehavestatedbeforeinsub-chapter7.3the

energyconsumptionineverystageisthemostinfluencingoneineverymid-pointindicator

analyzed.Anotherpossiblereasonthatcanhavecontributedinachievingthesevaluesis

thatthetransesterificationprocessusedforupgradingthebio-oilextractedfromthealgae

isnottheoneusedinthestudyof(5),whichisbasedontheGREETdataforconvertingsoy

oilintobiodiesel.Furthermore,thetransportdistancesconsideredinthetransesterification

processusedhavebeenmodifiedinordertoconsiderthedistancebetweencenterofItaly

andSwitzerland.

101

9.Conclusions

Inconclusionforthisthesiswork,wearegoingtoassesswhichisthebestenvironmental

wayofexploitingtheavailablebiomassforpoweringdifferentmid-sizedcars.

Wearegoingnowtocompareallthebiofuelsproducedinthecurrentcasesandinthe

optimizedonesseparately.Thiswillallowustosuggesttothereaderwhichcanbean

optimalenvironmentalwaytousetheaccessibleresources.

TwochartsfortheGWPmid-pointindicatorareshown.Thefirstoneispresentedforthe

currentscenario,thesecondfortheoptimizedone.

9.1CurrentScenario

Table37:GWPBaselineScenariopervkm

102

Consideringthecurrentavailabletechnologiessomeconclusionscanbesuggested:

1. Whenwoodbiomassisavailablethebestenvironmentalwaytoconvertitisto

gasifyitandsubsequentlyupgradeitintomethaneorotherwisethewood

chipscanbeburnedandconvertedinelectricity;

2. Ifmanurebiomassisavailableinstead,itsconversionintobiogasandthen

methaneorinelectricity,nowadaysdonotshowsgoodperformancesif

comparedtothefossilmethaneortheSwissaverageelectricitymix.

3. Hydrogenproductionthroughthebiomassgasificationstandsasareally

promisingsolution,ifcomparedwiththefossilbasedprocess.

4. Thealgaepathwaysnowadaysisnotaviablesolutionconsideringtheclimate

changeissues;

103

9.2OptimizedScenarioThefollowingchartwillshowthecomparisonbetweenthedifferentbiofuelsinvestigatedin

theoptimizedcases:

Themainconclusionsfromthischartarethefollowing:

1. Woodbiomasshasthepotentialityofbeingconvertedinmethane,electricityor

hydrogen,showingineverycasegreatperformances,ifcomparedwiththefossil

alternativesortheSwissenergymix;

Table38:GWPOptimizedScenariopervkm

104

2. Theoptimizationphaseassumedinouroptimizedscenario,showshoweventhe

anaerobicdigestionstepmayleadtogoodperformancesifcomparingthebio-

methanewiththefossilone.TheHTGprocessisstillagoodalternative,onwhich

wouldbebetterdeepenourtechnicalknowledge;

3. Algaeproducedinanoptimizedfacility,whereasubstantialcuthasbeenperformed

ontheenergydemandandemissions,revealtobeapromisingpathwayifwe

considertheenvironmentalsideofit;

9.3FinalConclusionAfterpresentingthechartscomparingthedifferentresultsobtainingincoveringone

kilometerbythedifferentmid-sizedcarsispossibletostatethatthisthesishasreachedhis

goaltoassesswhichisthebestenvironmentalwaytoexploitaspecificsourceofbiomass.

Themainconclusionisthatifwoodbiomassisavailablethebestenvironmentalmannerto

exploititistogasifyitortoburnittoproduceelectricityandheatinacogenerationplant.

Regardingmanurebiomass,whichinSwitzerlandhasabiggerpotentialthanwoodbiomass,

asithasbeenstatedinsub-chapter1.1,theproblemisthatnowadays,withthestateofart

technology,fromanenvironmentalpointofview,themainprocessknownnamelythe

anaerobicdigestionplantisnotagoodoption.Thisisbecausetheleakagesofmethane

fromthecoverofthestoragearehighlyaffectingthisprocess,sobiggereffortsmustbeput

intheresearchtofindasolutionforthisissue.

OnlytheHydrothermalGasificationprocessmightrepresentaviablesolution,because

avoidingtheanaerobicdigestionstepandsothemethaneleakages,betterresultsinevery

categorycanbeobtained.

Consideringinsteadthecultivationofthealgae,stillmanyproblemsmustbeovercome,if

thispathwaywantstobecomeapracticableone.Theresearchmustfocusitsattentionon

findingawaytomakethecultivationsteptheleastenergyintensivepossible.

Whataretheimprovementsthoughcomingfromthisthesistothescientificliterature?First

ofall,itisaresearchthatfocusesonlyontheavailablebiomasssourcesinSwitzerland,

assessingwhichcouldbethebestenvironmentalwaytoexploitthemforproducing

biofuels.KnowingthatallthestudiesusedhavebeenadaptedtotheSwisssituation,

meaningthatalltheinputs,transportunits,andenergiesarerelatedtotheSwisscontest.

EvenwhenthecultivationofalgaeandtheupgradeoftheiroilhastakenplaceinItalyfor

themoreoptimalweatherconditions,theecoinventprocessforthetransesterificationof

theoilextractedhasbeenadaptedtotheItaliancontest,andthetransportdistanceshave

beenconsideredfromthecenterofItalytoSwitzerland.Inaddition,forthealgaecultivation

stepalsotheinfrastructurehasbeenimplementedinthemodelingtoshowmorecomplete

results.

105

Furthermore,thedatausedfromtheavailablestudieswerealsoharmonizedinorderto

achievethegoalofthisthesis,whichistocomparedifferentcarpoweredbydifferentfuels

incoveringonekilometer.Thishasbeenthoughttobeagoodwaytocomparedifferent

biofuels,andtoallowaneasiercomparisonwithotherstudies.

Consideringinsteadapossiblecardriver,thisthesiscanhelphimdecidewhichfuelwould

bethebestenvironmentalchoice.Inthisway,hewillbeawarethatifhisconcernsare

towardstheenvironmentsomechoiceswillbebetterthanothers.Becauseofthatfor

exampleifheisdrivinganelectriccarhewouldliketoknowthattheelectricityusedfor

poweringit,iscomingfromthecombustionofwoodbiomassandnotfromtheaverage

Swissmix.

Theweaknessesinsteadofthisthesisresideinnothavingperformedanylifecyclecost

assessmentofthedifferentpathwaysexplored.Thisisduetothelackofavailabletimefor

exploringthismatter,butiswellknownthatanenvironmentalassessmentwouldgainmuch

morestrengthifaccompaniedbyaneconomicone.Forthefuture,thisisthedirection

wheretheresearchmustgoforcompletingthisstudy,becauseifanyofthisbiofuelisnot

economicallyconvenient,eveniftheenvironmentalresultsarereallygood,thereisno

actualwayofproducingbiofuelsstartingfromcertaintechnologiesthatremainjust

promising.

Furthermore,thedatausedforthenewprocesses(i.e.fastpyrolysis,HTG,algaecultivation

andupgrade)havebeentakenfromtheavailableliterature,butispossiblethatbetterdata

areavailableorcanbeproduced.

Anotherweakpointaboutthedatausedisthattheyareobtainednotfromexisting

facilities,onthecontrary,theyareobtainedaswellfromassumptionsandmodelingofthe

differentauthorsconsidered.Inanycasetheresultsobtainedevenfromtheoreticmodels

cangiveafirstoutlookonhowacertaintechnology,oracertainprocesswillperform,

pointingoutwherearetheareasonwhichisimportanttomakesomedevelopments,but

stilltheuncertaintiespersist.

106

10. Acknowledgements

IwouldliketostarttothankmysupervisorBrianCoxforhistime,advicesandprecioushelp

throughoutthisthesis.Hissupportwasfundamentalforreachingmygoalsandfinishingthis

work.ThenmythanksgotoProf.Lorenzoniforlettingmedothisexperienceabroadfrom

theUniversityofPadovaandforhissupport.

ThanksthentoallmycolleaguesoftheTechnologyAssessmentLab,especiallyDr.Peter

BurgherrtheleaderoftheTAgroup,AnnaKalinina,Dr.MatteoSpada,AnalyCastillo,Dhruv

Pandya,SalvatoreGrecoandRebeccaBishop.Itwasreallynicetomeetthesepeople,and

theirhelp,butalsotheircompanyduringthelunchbreakandthecommutingtoandfrom

PSImademefeellikeIwasathome.

ThanksalsotoProf.StephanHirschbergforhishelp,andfortheveryinterestingtalkswe

hadtogether.

Aspecialthankmustgotomyfamilyforitsendlesssupportinallmylife,andaswellinthis

occasion.

107

11. AppendixInthissectiontheresultsobtainedfortheproductionof1MJineverymid-pointindicatorwillbeshowed:

Table39:Dieselmid-pointresultsperMJ

108

Table40:Dieselmid-pointresultsperMJ

109

Table41:Methanemid-pointresultsperMJ

110

Table42:Methanemid-pointresultsperMJ

111

Table43:Gasolinemid-pointresultsperMJ

112

Table44:Gasolinemid-pointresultsperMJ

113

Table45:Hydrogenmid-pointresultsperMJ

114

Table46:Hydrogenmid-pointresultsperMJ

115

Table47:Electricitymid-pointresultsperMJ

116

Table48:Electricitymid-pointresultsperMJ

117

12. References

A.Dauriat,E.G.(2006).SyntheticBiofuels.RetrievedfromA.Wokaun,W.(2011)TransitiontoHydrogen-PathwaysTowardCleanTransportation

.AbhishekChaudhary,FrancescaVerones,LauradeBaan,StephanPfister,&Hellweg,S.

(2014).Landstress:Potentialspecieslossfromlanduse(global;PSSRg).11.Alonso-Vicario,A.,Ochoa-Gómez,J.R.,Gil-Río,S.,Gómez-Jiménez-Aberasturi,O.,Ramírez-

López,C.A.,Torrecilla-Soria,J.,&Domínguez,A.(2010).Purificationandupgradingofbiogasbypressureswingadsorptiononsyntheticandnaturalzeolites.MicroporousandMesoporousMaterials,134(1–3),100-107.doi:http://dx.doi.org/10.1016/j.micromeso.2010.05.014

Baier,p.U.(13.10.2016).Beal,C.M.,Gerber,L.N.,Sills,D.L.,Huntley,M.E.,Machesky,S.C.,Walsh,M.J.,...

Greene,C.H.(2015).Algalbiofuelproductionforfuelsandfeedina100-hafacility:Acomprehensivetechno-economicanalysisandlifecycleassessment.AlgalResearch,10,266-279.doi:http://dx.doi.org/10.1016/j.algal.2015.04.017

BIOSWEET.(2016).BiomassforSwissEnergyFutureConference2016.Brown,Brown,T.,Duan,P.,&Savage,P.(2010).HydrothermalLiquefactionandGasification

ofNannochloropsissp.Energy&fuels,24(6),3639-3646.Cavenati,S.,Grande,C.,&Rodrigues,A.(2005).UpgradeofMethanefromLandfillGasby

PressureSwingAdsorption.Energy&fuels,19(6),2545-2555.Cherubini,F.,Bird,N.D.,Cowie,A.,Jungmeier,G.,Schlamadinger,B.,&Woess-Gallasch,S.

(2009).Energy-andgreenhousegas-basedLCAofbiofuelandbioenergysystems:Keyissues,rangesandrecommendations.Resources,ConservationandRecycling,53(8),434-447.doi:http://dx.doi.org/10.1016/j.resconrec.2009.03.013

Chisti,Y.(2007).Biodieselfrommicroalgae.BiotechnologyAdvances,25(3),294-306.doi:http://dx.doi.org/10.1016/j.biotechadv.2007.02.001

DauriatA.,G.G.,AligM,ScharfyD,MembrezY,BachmannN,SteinerR.(2011).Analysedecycledeviedelaproductioncentraliséeetdecentraliséedebiogazenexploitationsagricoles.

E4tech.ComparisonofwoodcombustionandgasificationtechnologiesinthecontextoftheSwissEnergyStrategy2050.

EC.(2006).BiofuelsintheEuropeanUnion-avisionfor2030andbeyond.Ecoinvent.(2014).heatandpowerco-generation,woodchips,6667kW.

https://v33.ecoquery.ecoinvent.org/Details/UPR/03713B24-7420-4550-88AC-E4AF5157E3D4/290C1F85-4CC4-4FA1-B0C8-2CB7F4276DCE.

EPA.(2016).GlobalGreenHouseGasEmissionsData.https://www.epa.gov/ghgemissions/global-greenhouse-gas-emissions-data.

FederalDepartmentoftheEnvironment,T.,EnergyandCommunicationsDETEC,SwissFederalOfficeofEnergySFOE.(2016).EnergyConsumptioninSwitzerland2015.

H.Thomas.(2014).OpenAlgaeWetExtraction.C.M.Beal(Ed.)(www.openalgae.com).IEA.(2008).Energytechnologyperspective-Scenarioandstrategiesto2050.IEA.(2012).EnergyPoliciesofIEACountries-Switzerland.(Review).IEA.(2015).CO2EMISSIONSFROMFUELCOMBUSTION-Highlights.

118

Iribarren,D.,Peters,J.F.,&Dufour,J.(2012).Lifecycleassessmentoftransportationfuelsfrombiomasspyrolysis.Fuel,97,812-821.doi:http://dx.doi.org/10.1016/j.fuel.2012.02.053

ISO.(2006).Thenewinternationalstandardsforlifecycleassessment:ISO14040andISO14044.

KahnRibeiro,S.,S.Kobayashi,M.Beuthe,J.Gasca,D.Greene,D.S.Lee,Y.Muromachi,P.J.Newton,S.Plotkin,D.Sperling,R.Wit,,&Zhou,P.J.(2007).Transportanditsinfrastructure.ClimateChange2007:Mitigation.ContributionofWorkingGroupIIItotheFourthAssessmentReportoftheIntergovernmentalPanelonClimateChange[B.Metz,O.R.Davidson,P.R.Bosch,R.Dave,L.A.Meyer(eds)],

CambridgeUniversityPress,Cambridge,UnitedKingdomandNewYork,NY,USA..Luterbacher,Luterbacher,J.,Fröling,M.,Vogel,F.d.r.,Maréchal,F.o.,&Tester,J.(2009).

HydrothermalGasificationofWasteBiomass:ProcessDesignandLifeCycleAsessment.Environmentalscience&technology,43(5),1578-1583.

M.Spielmann,F.D.,K.Schleiss,N.Jungbluth.(2006).BiogasRetrievedfromMariluzBagnoud-Velasquez,D.R.,FrancoisVuille,andChristianLudwig.(2016).

OpportunitiesforSwitzerlandtocontributetotheproductionofalgalbiofuels:thehydrothermalpathwaytobio-methane.CHIMIA,10.

MarkA.J.Huijbregts,F.V.,LigiaB.Azevedo,AbhishekChaudhary,NunoCosme,PeterFantke,MarkGoedkoop,MichaelHauschild,AlexisLaurent,ChristopherL.Mutel,StephanPfister,TommiePonsioen,ZoranSteinmann,RosalievanZelm,MarisaVieira,StefanieHellweg.(2014).LC-Impactv0.1.

MarkGoedkoop,R.H.,MarkHuijbregts,AnDeSchryver,JaapStruijs,andRosalievanZelm.(2013).ReCiPe2008.

MireilleFaistEmmenegger,S.G.n.,JürgenReinhard,RainerZah,ThomasNemecek,JulianSchnetzer,ChristianBauer,AndrewSimons,GaborDoka.(2012).Harmonisationandextensionofthebioenergyinventoriesandassessment.Retrievedfrom

Morero,B.,Groppelli,E.,&Campanella,E.A.(2015).LifecycleassessmentofbiomethaneuseinArgentina.BioresourceTechnology,182,208-216.doi:http://dx.doi.org/10.1016/j.biortech.2015.01.077

Mu,Mu,D.,Min,M.,Krohn,B.,Mullins,K.,Ruan,R.,&Hill,J.(2014).LifeCycleEnvironmentalImpactsofWastewater-BasedAlgalBiofuels.Environmentalscience&technology,48(19),11696-11704.

N.Jungbluth,M.F.E.,F.Dinkel,C.Stettler,G.Doka,M.Chudakoff,A.Dauriat,E.Gnansounou,M.Spielmann,J.Sutter,N.Kljun,M.Keller,K.Schleiss.(2007).LifeCycleInventoriesofBioenergy(17).RetrievedfromUster:

Passell,H.,Dhaliwal,H.,Reno,M.,Wu,B.,BenAmotz,A.,Ivry,E.,...Ayer,N.(2013).Algaebiodiesellifecycleassessmentusingcurrentcommercialdata.JournalofEnvironmentalManagement,129,103-111.doi:http://dx.doi.org/10.1016/j.jenvman.2013.06.055

Prognos.(2012).DieenergieperspektivenfürdieSchweizbis2050-EnergienachfrageundElektrizitätsangebotinderSchweiz2000-2050.

R.Zah,H.B.,M.Gauch,R.Hischier,M.Lehmann,P.Wäger.(2007).LCAofenergyproducts:environmentalimpactassessmentofbiofuels.

Richard,T.L.(2010).ChallengesinScalingUpBiofuelsInfrastructure.Science,329(5993),793-796.doi:10.1126/science.1189139

119

SCCER-Mobility.SwissCompetenceCenterforEnergyResearch-EfficientTechnologiesandSystemsforMobility.http://www.sccer-mobility.ch/.

SimaPro.(2016).https://simapro.com/databases/ecoinvent/.Snowden-Swan,L.J.,Spies,K.A.,Lee,G.J.,&Zhu,Y.(2016).Lifecyclegreenhousegas

emissionsanalysisofcatalystsforhydrotreatingoffastpyrolysisbio-oil.BiomassandBioenergy,86,136-145.doi:http://dx.doi.org/10.1016/j.biombioe.2016.01.019

Spiellmann,M.(2005).UseandUpgradingofBiogas.RetrievedfromStefanHirschberg,C.B.,BrianCox,ThomasHeck,JohannesHofer,WarrenSchenler,Andrew

Simons,AndreaDelDuce,Hans-JörgAlthaus,GilGeorges,ThiloKrause,MarinaGonzálezVayá,FrancescoCiari,RashidWaraich,BorisJäggi,AlexanderStahel,AndreasFroemelt,DominikSaner.(2016).Opportunitiesandchallengesforelectricmobility:aninterdisciplinaryassessmentofpassengervehicles-FinalreportoftheTHELMAprojectinco-operationwiththeSwissCompetenceCenterforEnergyResearch“Efficienttechnologiesandsystemsformobility”.

Steubing,B.,Zah,R.,Waeger,P.,&Ludwig,C.(2010).BioenergyinSwitzerland:Assessingthedomesticsustainablebiomasspotential.RenewableandSustainableEnergyReviews,14(8),2256-2265.doi:http://dx.doi.org/10.1016/j.rser.2010.03.036

Stoppato,A.(2013).LCA-LifeCycleAssessmentABriefIntroduction.Surendra,K.C.,Takara,D.,Hashimoto,A.G.,&Khanal,S.K.(2014).Biogasasasustainable

energysourcefordevelopingcountries:Opportunitiesandchallenges.RenewableandSustainableEnergyReviews,31,846-859.doi:http://dx.doi.org/10.1016/j.rser.2013.12.015

T&M-Leuven.(2007).TREMOVEv2.7b,Transport&MobilityLeuven.Brussels,EuropeanCommission.

Thees,B.,Erni,Bowman,Lemm.(2017).BiomassepotenzialederSchweizfürdieenergetischeNutzung"(preliminaryresults,September2016).FinalreportSCCER-Biosweet.

UnitedStatesEnvironmentalProtectionAgency,O.o.A.a.R.,&OfficeofAtmosphericPrograms,C.C.D.(2014).FrameworkforAssessingBiogenicCO2Emissions

fromStationarySourcesWeinberg,J.,&Kaltschmitt,M.(2013).Lifecycleassessmentofmobilityoptionsusingwood

basedfuels–Comparisonofselectedenvironmentaleffectsandcosts.BioresourceTechnology,150,420-428.doi:http://dx.doi.org/10.1016/j.biortech.2013.08.093

www.agrammon.ch.www.agrammon.ch.Zhou,W.,Chen,P.,Min,M.,Ma,X.,Wang,J.,Griffith,R.,...Ruan,R.(2014).Environment-

enhancingalgalbiofuelproductionusingwastewaters.RenewableandSustainableEnergyReviews,36,256-269.doi:http://dx.doi.org/10.1016/j.rser.2014.04.073

Zhu,Y.,Albrecht,K.O.,Elliott,D.C.,Hallen,R.T.,&Jones,S.B.(2013).Developmentofhydrothermalliquefactionandupgradingtechnologiesforlipid-extractedalgaeconversiontoliquidfuels.AlgalResearch,2(4),455-464.doi:http://dx.doi.org/10.1016/j.algal.2013.07.003

Documents

UNIVERSITÀ DEGLI STUDI DI PADOVA - unipd.ittesi.cab.unipd.it/53980/1/Calabretta_Saverio_tesi.pdf · UNIVERSITÀ DEGLI STUDI DI PADOVA Dipartimento di Ingegneria Industriale Corso