AlternativesAnalysisonNon-LeadAlloysforPublicWaterSystemApplications

ElissaLoughman

Environment297A:LifeCycleAnalysisProfessorDeepakRajagopal

Spring2013

TableofContents:

I. Abstract

II. GoalandScope

III. LiteratureReview

IV. FunctionalUnit,SystemBoundaryandFlowDiagramandMethod

V. LifeCycleInventoryAnalysis

VI. LifeCycleImpactAnalysis

VII. SummaryofResults

VIII. ConclusionsandLimitations

IX. SensitivityAnalysisandOpportunitiesforAdditionalAnalysis

X. References

ListofFiguresandTables:

Table1:AlloyCompositionreportedbytheSTPPTeam

Table2.AlloyCompositionusedintheGaBiAnalysis

Table3.PrimaryManufacturingData–ElectricityuseandSlagg/Drossgeneration

Figure1.LifeCycleFlowDiagram

Figure2.Input-Outputmodel

Figure3.GaBiModelforC89833Lead-FreeBismuthBrass

Figure4.GlobalWarmingPotential

Figure5.OzoneDepletionPotential

Figure6.Ozoneformation

Figure7.SmogAir

Figure8.EutrophicationPotential

Figure9.InputComparison-GlobalWarmingPotential

Figure10.InputComparison–OzoneDepletionPotential

Figure11.InputComparison-PhotochemicalOzoneCreationPotential

Figure12.InputComparison-EutrophicationPotential(measuredinphosphorousequivalents)

I.Abstract

Lead has been recognized as being harmful to human health for several decades.

AccordingtotheEPA,studieshaveshownthatleadpoisoningcancauseanumberofadverse

human health effects, but is particularly detrimental to the neurological development of

children.Leadleachingintodrinkingwaterisonemechanismforexposureandposesaserious

healthriskaccordingtotheCentersforDiseaseControlandPrevention.Inanefforttoprotect

human health, the California Lead Plumbing Law, AB1953was enacted in 2006 and became

effectivein2010.Thisregulationphasesoutleadfrombrassplumbingusedtoconveydrinking

waterinwaterutilitydistributionpipesandconsumerplumbingfittingsandfaucets.Asof2010,

allplumbingcomponents inCaliforniahadtobe lead-free.Thisrequiredareductionfrom8%

leadinpipesorfittingsand4%leadinplumbingfittingsandfixturesto≤0.25%.Thislegislation

was followed by federal S. 3874 Reduction of Lead in Drinking Water Act that will apply

California’s AB 1953 throughout the United States. Implementation of this legislation will

commenceJanuary2014.Duetothisnewrequirement,lead-freealternativesmustbeusedfor

pipes,pipefittings,watermeters,valves,impellersandotherpublicwatersystemcomponents.

Inanefforttoselectthebestalternativeplumbingcomponentmaterialstousenationwide,a

group of researchers from the UCLA Sustainable Technology and Policy Program (STPP) has

begunconductingcomparativeresearchonfivealternatives.Inanefforttoincorporatelifecycle

systemthinkingtothisanalysis,phase6oftheplannedsixphasealternativesanalysisincludes

acomparisonofenvironmentalimpactsoverthelifecycleofpublicwatersystemcomponents.

The following report provides a comparative lifecycle analysis on five material options for

plumbing components using theGABI software. Two of thematerials tested contain greater

than.25%leadandwillbeusedasabaselinetocomparethethreethatcontainlessthan.25%

lead.The fivematerialscompared include:C84400 -Leadedsemi-redbrass,C83600 -Leaded

red brass, C89833 - Lead-free bismuth brass, C87850 - Lead-free silicon brass, and C87610 -

Lead-freesiliconbronze.

Theanalysisprovidespreliminaryinsightintotheimpactsofthefivealloysanalyzed.The

life cycle inventory analysis indicates that C87850 – Lead-free silicon brass had the lowest

impactsinallfourenvironmentalimpactcategories.Thisalloyhadthegreatest%ofzinc(21%)

whilethe%Zincintheotheralloysrangedbetween4and9%.Inthenextphaseofthisproject

additionalresearchwillbedonetoincorporatevariousotherfactorsofthelifecyclesofthefive

alloys.Thisresearchwillexploretheimpactsoftransportationinthesupplychain.Recyclingas

anendoflifeoptionwillalsobeanalyzedaswellasthepotentialtouserecycledcontentinthe

manufacturingofeachofthealloys.Lastlycostandresourceavailabilitywillbeexamined.

II.GoalandScope

Thegoalofthisanalysisistoevaluatethepotentiallife-cycleenvironmentalimpactsof

selected lead-based and lead-free alloy alternatives using LCAmethodologies. The life cycle

stagesthatwereassessedareresourceextraction,metalprocessing,alloymanufacturingand

theassociatedenergyuseateachof those stages.This informationprovidedby thisanalysis

willbeusedinthelargerUCLASustainableTechnologyandPolicyProgram(STPP)comparative

researchonthesefivealternativesasoneofmanyfactorsthatwillbeusedtodeterminewhich

castingalloywillbeselectedtoreplacepipesthatcontainlead.Thisanalysiscanalsobeusedto

indicatewhichalloycomponentsresultinthegreatestenvironmentalimpacts.

Inadditiontothemainresearchgoals,thereisadditionalinteresttoevaluatetheeffects

transportation and using recycled alloys and reclamation at end-of-life. This additional

evaluationwillbepartof the larger reviewof these5alternativesandwasnot incorporated

intotheLCAprojectforENV297Aduetotimeconstraints.

III.LiteratureReview

“LCA of Manufacturing Lead-Free Copper Alloys” by Atsushi Nakano, Nurul Taufiqu

RochmanandHidekazuSueyoshiprovidedanalysisthatwasthemostsimilartothisresearchin

that it focused on a lead-free alternatives assessment for copper alloys commonly used in

waterfaucetsandpipesforfreshwaterservice. Itdidhoweverdifferfromthisstudyinthat it

usedtheJEMAI-LCAsoftwaredevelopedbytheJapanEnvironmentalManagementAssociation

for Industry. In addition, a large part of this study was focused on comparing lead-free

alternativesmadewithvirginmetalsvs.lead-freealternativesmadewithrecycledmetals.The

goaloftheirstudywastodetermineifitwastrulylessharmfultotheenvironmenttouseanew

technology that removed lead from copper alloys in order to recycle those copper alloys in

futureplumbingpiping.They foundthat theconversionof theconventionalsystemthatuses

virgin materials into a new system that uses lead free copper alloy scrap decreases

environmentalimpacts.Thereducedimpactsareattributedtothefactthatvirginmaterialsare

notusedandadecreaseinenergyconsumptioninthecastingprocess.Thisstudywillbevery

valuablewhenanalyzingtherecyclingpotentialofthe5alloysreviewedinthisproject.

InadditiontotheLead-FreeCopperAlloystudy, Iwasabletofindseveralpapersthat

focused on lead-free alternatives assessments for other industrial applications. The US EPA

Lead-FreeSolderstudy“Solders inElectronics:ALifeCycleAssessment”byJackR.Geibigand

Maria L. Socolof, proved to be quite helpful during this process. The structure of the study

providedamodelforhowapproachanalternativesanalysisofmetalalloysandrevealedhow

the GaBi platform could be utilized for such an analysis. The metal alloys compared in the

solderstudyinclude,Tin-Lead(SnPB),Tin-Copper(SnCu),Tin-Silver-Copper(SAC),Bismuth-Tin-

Silver(BSA)andTin-Silver-Bismuth-Copper(SABC).Tin,Copper,Lead,andBismuthareinthe5

metalalloysbeingcomparedinthispaper.

InadditiontotheUSEPALead-freeSolderstudy,Icameacrossareviewofseverallead-

free solder alternative LCA assessments that summarized the finding of each of studies. “A

reviewofLifeCycleAnalysis(LCA)modelinginthedevelopmentofRoHAandWEE”bySophie

Parsons provides a comparisonof the various LCA approaches that havebeen conductedon

lead-free alternatives in electronics soldering over the past 10 years (Parsons, 2012). These

studiesanalyzetheperformanceofthesamealloyscomparedintheUSEPALead-freeSolder

study. She reviewed three approaches, the Metal Ecology Approach, the US EPA study

conductedin2005,andtheEndpointLCA.

Metal Ecologyapproachhighlighted thateachmetal cycle is linkedwithmanyothers,

forexamplebismuthproduction is reliantupon theproductionof lead. In regards toprocess

andextraction impacts there shouldnotbemuchdifferencebetweenbismuthand lead.The

MetalEcologystudypointedoutthatbydecreasingleadusetherewouldbeaneedtoreplace

itwithanothermetalthatwillalsohaveimpactsfromtheextractionandprocessphases.

Parsons pointed out that theUS EPA study showed that two of the lead-free solders

(Sn/Ag/CuandSn/Ag/Bi/Cu)hadgreater impacts than the lead solderoverall. TheSn/Ag/Cu

solder scored higher than the lead solder for energy use, landfill space, globalwarming and

acidification. However, Sn/Cu, a lead free option, had the lowest impacts for all the solders

tested.

TheEndpointLCAshoweda10%increaseinglobalwarmingpotentialintheshiftfroma

lead solder to a lead-free solder. The results showed that air toxicity and water toxicity

decreasedbyusingalead-freealternative,howevertheoverallresultsshowedthattheshiftto

leadfreewill likelyresultinhigherenvironmentalimpactsthantheleadfreeoptions.Parsons

alsoreferstotwootherstudiesconductedin2001and1996thatfoundthattherewasnoclear

environmental advantage to lead free solders (Turbini, 2001) and that hazard values and

toxicity potentials have shown tobehigher for some lead-free solders. (Socolof et al., 2003)

Parsons concluded that the life cycle systems thinking approach has showed lead-free

alternatives tobeas impactingas leadsolders,andhavinggreater impacts in termsofglobal

warmingpotential,ozonedepletionandenergyuse.ThesummarybyParsonsprovidedinsight

intothecomplexityofmetalalloysandtheirenvironmentalimpactsandprovidedevidencethat

theleadfreeoptionsmaynothavelessenvironmentalimpactsthattheleadedoptions.

“TheLifeCycleofCopper, itsCo-ProductsandBy-Products”byRobertU.Ayers,Leslie

W. Ayers and Ingrid Rade was also quite helpful in conducting the assessment. The report

provided essential background information on the variousmetals in the 5 alternatives being

reviewedfortheassessment.Theinformationprovidedinthereportonantimonyandbismuth

was particularly helpful. Antimony, and bismuth are associatedwith the production of lead,

zinc, and copperores.Once the `parent’mineralshavebeen concentratedand smelted, it is

feasible toseparateandextract theseminorcontaminants in secondaryprocesses.Antimony

andBismutharecomponents insomebutnotallofthe5metalalloyalternatives.Thearticle

alsoprovideddetailedinformationaboutcopper,whichistheprimarycomponentusedinall5

ofthemetalalloyalternatives.Commercialgradesofcathodecoppertodayrangefrom99.95%

to99.97%pure.Copperproductioniscurrentlymuchlessenergy-intensivethanaluminum(c.

60GJ/tforcopperfromaverageore)andaslittleashalfofthatforthemostefficientrefiners

vs.175GJ/tforaluminum).Sinceabouthalfofthisisformaterialshandlingandconcentration,

this energy advantage will disappear as the grade of copper ore mined approaches the

mineralogicalbarrier(around0.1%grade).Atthatpointenergycostswillsharplyincreasethe

economic incentives for copper recovery and recycling instead of mining virgin ore. This

information will be valuable in when evaluating the value of using recycled metals in alloy

productionandrecyclingthealloysattheendoftheirusefullife.

IV.FunctionalUnit,SystemBoundaryandFlowDiagram

Thefunctionalunitforeachofthealloysbeinganalyzedis100kgofingot.Thecradle-

to-grave system for these alloys includes five life-cycle stages: (1) raw materials

extraction/acquisition; (2) materials processing; (3) product manufacture; (4) product

use/application, and (5) final disposition/EOL. The flow diagram below depicts the fivemain

life-cyclestagesforeachofthemetalalloys.Thisanalysisincludesthefirstthreestagesofthe

lifecycle.

Figure1.LifeCycleFlowDiagram

V.LifeCycleInventoryAnalysisandMethod

TheLifeCycleInventoryforthisanalysisincludedtheidentificationandquantificationof

the material and resource inputs as well as emissions and product outputs from the unit

processes included in the life cycle of all five metal alloys. For the plumbing components

analyzed,theinputsincludematerialsusedinthe5castingalloyalternatives,energyandother

resourcesconsumed in themanufacturing,use,andendof lifeof thealloys.Outputs include

finalmetalproducts,airemissions,watereffluents,andwaste.

Figure2.Input-Outputmodel

Inputs:Materials,EnergyandResources

MaterialsExtraction:Extractionofeachmetalinthecastingalloy.

MaterialsProcessing:Processingofeachmetalinthecastingalloy.

ProductManufacture:Manufacturingofeachcastingalloyandmoldingtheproduct.

ProductUse:Useofcastingalloyasaplumbingcomponent.

EndofLife:Recycling,landfilling,incineration,othermodesofdisposal.

Outputs:Products,Emissions,Effluents,Waste

Thismodelappliestoallfivealloyalternatives.Theprimarymaterialsbeingevaluatedin

theupstreamlife-cyclestagearethebasemetalsineachcastingalloyalternative.Thesemetals

include aluminum, antimony, bismuth, copper, iron, lead, manganese, nickel, phosphorous,

silicon,sulfur,tinandzinc.TheSTPPResearchteamreportedthefollowingAlloyComposition

forthe5alternativesanalyzed.

Table1.AlloyCompositionreportedbytheSTPPTeam

C84400

LeadedSemi-

RedBrass

C83600

LeadedRed

Brass

C89833Lead-

FreeBismuth

Brass

C87850Lead-

FreeSilicon

Brass

C87610Lead-

FreeSilicon

Bronze

Aluminum 0.005max 0.005max 0.005max

Antimony 0.25max 0.25max 0.25max 0.10max

Bismuth 1.7-2.2

Copper 79.0-82.0 84-86 86.0-91.0 75.0-78.0 90.0min

Iron 0.35max 0.25max 0.30max 0.10max 0.20max

Lead 6.3-7.7 4.0-5.7 0.09max 0.09max 0.09max

Manganese 0.10max 0.25max

Nickel 0.8max 0.8max 1.0max 0.20max

Phosphorous 0.02max 0.03max 0.050max 0.05-0.20

Silicon 0.005max 0.005max 0.005max 2.7-3.4 3.0-5.0

Sulfur 0.08max 0.08max 0.08max

Tin 2.3-3.5 4.3-6.0 4.0-6.0 0.3max

Zinc 7.0-10.0 4.3-6.0 2.0-6.0 Rem. 3.0-5.0

(Sinsheimer,2011)

TheSTPPresearchgroupprovidedrangesforthecompositionofsomeofthealloys.The

middlepointintherangesforeachmetalwasusedforeachalloy.Inordertoensurethatthe

percentagesaddupto100%ofthequantityofmetal,coppervariedwithinitsgivenrange.This

wasdonebecausecopperistheprimarycomponentforall5ofthealternativesandmakesup

thegreatestpercentageofeachmetalalloy.Table2showstheexactvaluesused intheGaBi

LCAmodelofthe5plumbingalloyalternatives.

Table2.AlloyCompositionusedintheGaBiAnalysis

%

C84400

LeadedSemi-

RedBrass(kg)

C83600

LeadedRed

Brass(kg)

C89833Lead-

FreeBismuth

Brass(kg)

C87850Lead-

FreeSilicon

Brass(kg)

C87610Lead-

FreeSilicon

Bronze(kg)

Aluminum 0.00257 0.00205 0.00255

Antimony

Bismuth

1.95

Copper 82.7 86.5 90.3 78 94

Iron 0.18 0.127 0.153 0.0505 0.1

Lead 7.19 4.93 0.045 0.0455 0.0462

Manganese

0.0505 0.128

Nickel 0.411 0.408 0.51 0.101

Phosphorous

Silicon 0.0038 0.00205 0.00306 3.03 4.02

Sulfur 0.0411 0.0411 0.0408

Tin 2.98 5.24 5.1 0.0152

Zinc 8.73 5.24 4.08 21 4.02

Method

Theanalysisofthefivematerialoptionsusedforplumbingcomponentswasdoneusing

theGABI software. Two of thematerials tested containmore than .25% lead andwill be to

comparethethreethatcontain lessthan.25%lead.Theanalysisfocusesonthematerialand

energyinputsrequiredtomanufacturethe5options.TheGaBilifecycledatabasewasusedto

providesecondarydataforthefirsttwolifecyclestagesforthefivealloyalternatives.TheUCLA

STPPgroupanalyzed theProductManufacture stage (step3 shown inFigure1).Theprimary

data they gathered was incorporated into this analysis. The STPP research team gathered

energyusedata,metalwastedata,andmeasurementsofslagg/drossproduced.Themetalloss

wasfactoredintotheparametersoftheGaBimodel.Eachmetalhaddifferentlossrates,which

wereusedasparametersintheGaBimanufacturingprocessmodel.Inadditiontoincludingthe

manufacturinglossinthemanufacturingprocess,theamountofslagg/drossmeasuredbythe

UCLAstudentswasincludedasanoutputforeachofthe5metalalloys.

Table3.PrimaryManufacturingData–ElectricityuseandSlagg/Drossgeneration

C84400

Leaded

Semi-Red

Brass

C83600

Leaded

RedBrass

C89833

Lead-Free

Bismuth

Brass

C87850

Lead-Free

Silicon

Brass

C87610

Lead-Free

Silicon

Bronze

Weight(lbs.) 4,000.00 4,000.00 4,000.00 4,002.00 4,000.00

QuantityofallowinLCA

model(kg) 100.00 100.00 100.00 100.00 100.00

%oftotalmadeupby100kg 0.06 0.06 0.06 0.06 0.06

ElectricityUse(kWh) 690.60 759.30 746.00 663.50 772.40

Electricityusefor100kg(MJ) 137.03 150.66 148.02 131.58 153.26

Slagg/Dross(lbs.) 62.00 48.00 42.00 8.00 8.00

Slag/Drossfor100(kg) 1.55 1.20 1.05 0.20 0.20

Secondarydatawasusedtomeasuretheimpactsofthevariousmetalinputsforthe5

alternatives. The extraction and processing of these metals is included in the scope of this

analysis. The extraction andprocessing (e.g., smelting) of eachmetal are combined intoone

processinventoryintheGaBiSoftware.TheGaBisoftwarehowever,didnothaveprocessdata

forallofthemetalsused.GaBiismissingprocessdataforantimony,bismuthandphosphorous.

Because antimony and phosphorous were not key components in any of the 5 alloys and

becausetherewasn’tanyprocessdatathatwasclearlysimilartothosetwocomponentsinthe

GaBidatabase,proxydatawasnotusedtoreplicatethe impactofantimonyorphosphorous.

Thesetwometalcomponentswerenotincludedinthemodel.Bismuthisakeycomponentin

C89833 lead-freebismuthbrassand thus important to include in this analysis.Bismuth's is a

byproductofextractionofothermetals suchas lead, copper, tin,molybdenumand tungsten

(Krugeretal.,2003).Bismuthhoweverisprimarilyaby-productofleadrefining(Jebuohoh,etal

1992). Bismuth travels in crude lead bullion (which can contain up to 10%bismuth) through

several stages of refining, until it is removed. Because it is most commonly found in lead

extractionandrefining,leadextractiondatawasusedasproxydataforbismuth.Bismuthisin

oneofthe5alternatives.TheamountofbismuthinC89833isaccountedforbyincreasingthe

leadcontent in themanufacturingprocessby theamountofbismuth required (1.95kg).The

GaBimodels foreachof the5metalalloyalternativesmirrorthatofLead-freebismuthbrass

shownbelow.

Figure3:GaBiModelforC89833Lead-FreeBismuthBrass

VI.LifeCycleImpactAnalysis(LCIA)

The GaBi software provides assessment of environmental impacts such as global

warmingpotential (GWP),acidification, impacts tohumanhealthandresourcedepletion.For

the purposes of this report, themain areas of impact thatwill be assessed areGWP, ozone

depletion, ozone creation and eutrophication. GaBi has five different data

sources/methodologiesthat itutilizestoprovide lifecycle impactanalysis.Thesefive include:

ReCiPe LCIA methodology developed by RIVM, CML, PRe Consultants, Radboud Universiteit

Nijmegen,andCEDelft;TRACI -TheTool for theReductionandAssessmentofChemicaland

OtherEnvironmentalImpactsdevelopedbytheUSEPA;ILCD,whichistheEuropeanPlatform

onLifeCycleAssessmentprovidedbytheEuropeanCommission, JointResearchCentre(JRC);

LCIA CML 2001, which is developed by the Institute of Environmental Sciences, Leiden

University,TheNetherlands;lastlyisaLCIAmethodology,however,itisnotmadeclearonthe

PEinternationalwebsitewhodevelopedit.

Theenvironmentalimpactsofthefivealloysinthefourdifferentenvironmentalimpact

categoriesareasfollows:

Figure3.GlobalWarmingPotential-All5LCIAmethodsusedinGaBireportedthesameGlobalWarmingPotentialforeachofthe5alloys.

GWP

C83600 Lead...C84400 Lead...

C87610 Lead...C87850 Lead...

C89833 Lead...

Clim

ate

chan

ge [k

g CO

2-Eq

uiv.]

2,500.0

2,000.0

1,500.0

1,000.0

500.0

0.0

Figure4.OzoneDepletionPotential-All5methodshadthesamefindingsregardingthealloysthathadthemostandleastODP.ILCDandTRACIreportedtheODPinunitsofR-11equivalentsshowninthebargraphontheleft.TheLCIA,LCIACML2001andReCiPeusedunitsofEtheneequivalents,showninthebargraphontheright.

Figure5.PhotochemicalOxidantFormation/PhotochemicalOzoneCreationPotential-All5methodshadthesamefindingsregardingthealloysthathadthemostandleastozoneformationpotential.ILCDandReCiPereportedtheODPinunitsofNMVO(Non-methanevolatileorganiccompound)equivalentsshowninthebargraphontheleftandLCIAandLCIACML2001usedunitsofEtheneequivalents(showninthebargraphontheright).

ODP, steady state

C83600 Lead...C84400 Lead...

C87610 Lead...C87850 Lead...

C89833 Lead...

Ozo

ne D

eple

tion

[kg

R11

-Equ

iv.] 8.0e-6

7.0e-6

6.0e-6

5.0e-6

4.0e-6

3.0e-6

2.0e-6

1.0e-6

0.0e-6

ODP, steady state

C83600 Leade...C84400 Leade...

C87610 Lead-...C87850 Lead-...

C89833 Lead-...

Ozo

ne L

ayer

Dep

letio

n P

oten

tial [

kg R

11-E

quiv

.]

7.0e-6

6.0e-6

5.0e-6

4.0e-6

3.0e-6

2.0e-6

1.0e-6

0.0e-6

Photochemical oxidant formation

C83600 Lead...C84400 Lead...

C87610 Lead...C87850 Lead...

C89833 Lead...

Pho

toch

emic

al o

xida

nt fo

rmat

ion

[kg

NM

VO

C]

5

4

3

2

1

POCP

C83600 Leaded...C84400 Leaded...

C87610 Lead-F...C87850 Lead-F...

C89833 Lead-F...

Pho

toch

em. O

zone

Cre

atio

n P

oten

tial [

kg E

then

e-E

quiv

.]

.9

.8

.7

.6

.5

.4

.3

.2

.1

Figure6.SmogAir-TheTRACImethodologymeasurementofozonedifferedslightlyfromtheotherfourmethodologiesandwasmeasuredinozoneequivalents.

Figure7.EutrophicationPotential–TheTRACImethodologymeasuredeutrophicationpotentialin termsofNitrogenequivalents (shownon the left)whereas theother fourmeasured it interms of Phosphorous equivalents. ILCD, and ReCiPe LCIA and LCIA CML 2001 all measuredPhosphorous equivalents and showed the same results. The difference in the unit ofmeasurementresultedindifferentfindingsforeutrophicationpotentialforthefivealloys.

Smog Air

C84400 Lea...C89833 Lea...

C87610 Lea...C83600 Lea...

C87850 Lea...

Sm

og A

ir [k

g O

3-E

quiv

]

100.0

80.0

60.0

40.0

20.0

0.0

EP

C83600 Lead...C84400 Lead...

C87610 Lead-...C87850 Lead-...

C89833 Lead-...

Eut

roph

icat

ion

[kg

N-E

quiv

.]

.3

.2

.1

Freshwater eutrophication

C83600 Lea...C84400 Lea...

C87610 Lea...C87850 Lea...

C89833 Lea...

Fre

shw

ater

eut

roph

icat

ion

[kg

P e

q]

8.0e-4

6.0e-4

4.0e-4

2.0e-4

0.0e-4

Inadditiontocomparingthe5alloys,Icreatedseparate,metalspecificmodelsinGaBi

to compare the impacts of the various inputs. Equal amounts of each metal input were

compared,withthefunctionalunitbeing1kgofeachmetal.Thegoalwastodeterminewhich

metal inputs have the greatest impact and then use that information in future sensitivity

analysistominimizetheoverallimpactsofthealloys.

The data above showed that environmental impact results from the 5 different

methodologies used in GaBi were very consistent. The ILCD methodology was used for the

comparisonofthemetal inputs.Copperhadthegreatest impactsbyfar ineachcategoryand

was separated in order to evaluate the impacts of the various other impacts. The data for

bismuth is consistentwith the five alloy analysis above. TheGaBi database does not include

bismuthsoleadproxydatawasusedinplaceofbismuthspecificdata.

Figure9.InputComparison-GlobalWarmingPotential

Figure10.InputComparison–OzoneDepletionPotential

GWP

AluminumBismuth

IronLead

ManganeseNickel

SiliconSulphur

TinZinc

Clim

ate

change [

kg C

O2-E

quiv

.]

10.0

8.0

6.0

4.0

2.0

0.0

GWP

GLO: Copper cathode (primary) ICA

Clim

ate

change [

kg C

O2-E

quiv

.]

3,500.0

3,000.0

2,500.0

2,000.0

1,500.0

1,000.0

500.0

0.0

ODP

AluminumBismuth

IronLead

ManganeseNickel

SiliconSulphur

TinZinc

Ozone D

eple

tion P

ote

ntial 3.0e-9

2.5e-9

2.0e-9

1.5e-9

1.0e-9

0.5e-9

0.0e-9

ODP, steady state

GLO: Copper cathode (primary) ICAOzone D

eple

tion [

kg R

11-E

quiv

.]

8.0e-5

6.0e-5

4.0e-5

2.0e-5

0.0e-5

Figure11.InputComparison-PhotochemicalOzoneCreationPotential

Figure12.InputComparison-EutrophicationPotential(measuredinphosphorousequivalents)

Thechartsaboverevealthatcopper,aluminumandnickelhavethegreatestglobal

warmingpotentialandthegreatestozonedepletionpotential.Copper,tinandsiliconhavethe

greatestphotochemicalozonecreationpotentialandeutrophicationpotential.

VII.SummaryofResults

Global warming potential (GWP) is measured in terms of carbon dioxide (CO2)

equivalents.C84400-Leadedsemi-redbrasshadthegreatestCO2emissionsbyfarwhilethe

C89833-Lead-freebismuthbrasshadthenextgreatestimpactsandthehighestimpactsofthe

3 lead freeoptions.C87850-Lead-freesiliconbrasshadthe leastGWP.Theozonedepletion

POCP

AluminumBismuth

IronLead

ManganeseNickel

SiliconSulphur

TinZinc

Photo

chem

ical O

zone f

orm

ation [

kg N

MV

OC

Equiv

.]

POCP

GLO: Copper cathode (primary) ICA

Photo

chem

ical O

zone f

orm

ation [

kg N

MV

OC

Equiv

.]

14

12

10

8

6

4

2

EP

AluminumBismuth

IronLead

ManganeseNickel

SiliconSulphur

TinZinc

Eut

roph

icat

ion

Pot

entia

l 3.5e-3

3.0e-3

2.5e-3

2.0e-3

1.5e-3

1.0e-3

0.5e-3

0.0e-3

EP

GLO: Copper cathode (primary) ICA

Eutr

ophic

ation P

ote

ntial [k

g P

hosphate

-Equiv

.]

1.4

1.2

1

.8

.6

.4

.2

potential (ODP)of a chemical compound is the relative amountof degradation to theozone

layer itcancause,withtrichlorofluoromethane(R-11orCFC-11)beingfixedatanODPof1.0.

CFC11,orR-11hasthemaximumpotentialamongstchlorocarbonsbecauseofthepresenceof

three chlorineatoms in themolecule.C84400-Leaded semi-redbrasshad thegreatestozone

depletion potential. Of the three lead free alternatives, C87610-Lead-free silicon bronze had

thegreatestozonedepletionpotentialandC87850-Lead-freesiliconbrasshadtheleast.

TheGaBisoftwareprovidedthreeunitsofmeasurementforozoneformation,including

photochemical oxidant formation and photochemical ozone creation potential and smog

potential. ILCD and ReCiPe reported the ozone formation in units of NMVO (Non-methane

volatile organic compound) equivalents and LCIA and LCIA CML 2001 used units of Ethene

equivalents.TRACImeasuredinunitsofOzone(O3)equivalents.Non-methanevolatileorganic

compounds (NMVOCs) are a collection of organic compounds that differ widely in their

chemicalcompositionbutdisplaysimilarbehaviorintheatmosphere.NMVOCsareemittedinto

the atmosphere from a large number of sources including combustion activities, solvent use

andproductionprocesses (i.e.paintapplicationanddrycleaning).NMVOCscontributeto the

formation of ground level (tropospheric) ozone. Quantifying the emissions of total NMVOCs

providesanindicatoroftheemissionsofthemosthazardousNMVOCs.LCIAandLCIACML2001

measuredozone formation in termsofPhotochemicalOzoneCreationPotential (POCP)using

unitsofEthene.Etheneisinreferencetoolefineethylene.Thephotochemicaloxidationisthe

result of reactions that take place between nitrogen oxides (NOx) and volatile organic

compounds (VOC)exposed toUVradiation.TheTRACImethodmeasuredozone formation in

terms of ozone equivalents and the results varied slightly from the results of the other 4

models. The alloys with the highest and lowest impacts however were the same for all 5

methods. C84400-Leaded semi-red brass had the highest capacity to produce ozone and

C87850-Lead-freesiliconbrasshadtheleast.OfthethreeleadfreealternativesC89833-Lead-

freebismuthbrasshadthegreatestozoneproductionpotential.

The TRACI methodology measured eutrophication potential in terms of Nitrogen

equivalentswhere as theother fourmeasured it in termsof Phosphorous equivalents. ILCD,

ReCiPe,LCIAandLCIACML2001allmeasuredPhosphorousequivalentsandshowedthesame

results. The difference in the unit of measurement resulted in different findings for

eutrophication potential for the five alloys. However, when only looking at the 3 lead free

alternatives,inbothcasesC87850-Lead-freesiliconbrasshadtheleasteutrophicationpotential

andC89833-Lead-freebismuthbrasshadthegreatest.

Insummary,C84400Leadedsemi-redbrasshadthegreatest impacts inall fourofthe

areasof impactevaluated.Ofthethree lead-freealloys,C89833Lead-freebismuthbrasshad

the greatest impacts in terms of eutrophication potential, ozone production and global

warmingpotential.IthadslightlylowerimpactsthanC87610-Lead-freesiliconbronzeinterms

of ozonedepletion.Of the three lead-free options, C87850 – Lead-free siliconbrass had the

lowestimpactsinallfourenvironmentalimpactcategories.

Intermsofthemetalinputscomparison,copperhadexponentiallygreaterimpactsinall

fourenvironmental impact categories.Copper, aluminumandnickelhave thegreatestglobal

warmingpotentialandthegreatestozonedepletionpotential.Copper,tinandsiliconhavethe

greatestphotochemicalozonecreationpotentialandeutrophicationpotential.

VII.LimitationsandConclusions

In many ways the results calculated using the GaBi software and shown above are

tremendously accurate. The GaBi software contains very detailed data on the processes

involved in extractingmetals andmanufacturingmetal alloys. Thatbeing said, this studyhas

several limitations.Dataspecifictoantimony,bismuthandphosphorousaremissingfromthe

inputstothemetalalloys.Proxydatafromleadextractionwasusedinplaceofdataspecificto

bismuth. In addition, this LCA based primarily on secondary data that might not accurately

represent the exact processes or locations involved in manufacturing the five alloys. Lastly,

there are numerous areas of impact that can be evaluated. For this particular report, GWP,

ozone depletion, ozone creation and eutrophication were evaluated. The findingsmay have

difference if different areas of impact such as acidification, impacts to human health and

resourcedepletionwerethefocus.

Despitetheselimitations,theanalysisprovidesapreliminaryideaoftheimpactsofthe

fivealloysanalyzed.The lifecycle inventoryanalysisclearly indicatesthatC87850–Lead-free

siliconbrasshadthelowestimpactsinallfourenvironmentalimpactcategories.Thisalloyhad

thegreatest%ofzinc(21%)whilethe%Zincintheotheralloysrangedbetween4and9%and

thelowest%ofCopper(78%).Inadditionaluminum,sulphurandbismuthwerenotinputsto

C87850 – Lead-free silicon brass and it containedminimal tin and nickel. C87610- Lead-free

siliconbronzedoesnotcontainaluminum,sulphur,bismuth,nickel,ortinbutithasthehighest

percentage of copper (94%) of all five alloys. A sensitivity analysis will be conducted in the

comingweekstoevaluatehowloweringthepercentofcopperinthevariousalloyswillaffect

theoverallenvironmentalimpacts.Thisfindingissignificantandleadstoadditionalquestions,

regardingavailabilityandfunctionalityoftheproductsifthepercentofcoppercanbereduced

and replaced by increasing other inputs such as zinc and silicon or replaced using recycled

copper.Italsoraisesquestionsabouthowcostofthealloyswillbeaffectedbyusinglessvirgin

copper.Leadfreealloysareessentialtoensuringsafedrinkingwater.Theyhowevercanresult

in other less available metals being relied upon to replace lead. For example, most of the

developed lead-free copper alloys are manufactured from virgin materials and Bismuth is

addedasasubstituteelementforlead.Ifthispracticeofusingvirginmaterialscontinues,the

resource consumption of Bismuth,which is a raremetal, but also of Copper, Zinc and silver

increases (Nakano et al., 2005). Additional researchwill have to be done in order to ensure

certainty that the lead free alternatives do not have additional environmental impacts that

havenotbeenaccountedforinthisanalysis.

IX.SensitivityAnalysisandOpportunitiesforAdditionalAnalysis

Thenextphaseofthisresearchwillincludeasensitivityanalysisfocusedontheamounts

ofthekeymetalsinthealloys.Thiswillprovideinsightintohowvariationintherangesaffects

theenvironmental impactsofeachof thealloys.Copper, SiliconandZincwill beused in the

sensitivityanalysis andwill providean indicationofhoweachof the componentsaffects the

environmentalimpactsofthealloy.AMonteCarloanalysiswillalsobeincludedtosimulatea

casewherethereare1,000differentvariationsofoursensitivitycriteria.

In addition to conducting a sensitivity analysis, additional research will be done to

incorporatevariousotheraspectsofthelifecyclesofthefivealloys.Thisresearchwillexplore

theimpactsoftransportationinthesupplychain.Recyclingasanendoflifeoptionwillalsobe

analyzedaswellasthepotential touserecycledcontent inthemanufacturingofeachofthe

alloys.Lastlycostandresourceavailabilitywillbeexamined.

References

AyresR.U.,AyresL.W.andRadeI.(2002).TheLifeCycleofCopper,itsCo-ProductsandBy-ProductsGeibigJ.R.andSocolfM.L.(2005).SoldersinElectronics:ALife-CycleAssessmentJebuobohF.K.(1992)."Bismuth—Production,properties,andapplications."JOM44(4):46–49KrugerJ.,WinklerP.,LuderitzE.,LuckM.andUweH.(2003).Bismuth,BismuthAlloys,andBismuthCompounds,WolfUllman’sEncyclopediaofIndustrialChemistryNakanoA.,RochmanN.T.andSueyoshiH.(2005).“LCAofManufacturingLead-FreeCopperAlloys.”MaterialsTransactions46:2713-2718ParsonsS.(2012).AReviewofLifeCycleAnalysis(LCA)ModelingintheDevelopmentofRoHSandWEEESinsheimerP.,GuptaV.,CornieJ.,AlvarezE.,AbrahamS.,RobackR.,GeG.andSanLaiK.(2011).AlternativesAnalysisonNon-LeadAlloysforPublicWaterSystemApplications:ResultsSocolofM.,GeibigJ.andSwansonM.(2003)."Cradletogatetoxicimpactsofsolders:acomparisonofimpactassessmentmethods."IEEE

TurbiniL.(2001).“ExaminingtheEnvironmentalImpactofLead-FreeSolderingAlternatives”,

IEEETransactionsonElectronicsPackagingManufacturing24(1)