Exergoecology Assessment of Mineral Exports from Latin America

18 Pages·2017·2.54 MB·English

sustainability
Article
Exergoecology Assessment of Mineral Exports from
Latin America: Beyond a Tonnage Perspective
Jose-LuisPalacios1,* ID,GuiomarCalvo2,AliciaValero2 ID andAntonioValero2 ID
1 DepartamentodeIngenieríaMecánica,EscuelaPolitécnicaNacional,LadróndeGuevaraE11253,
P.O.Box17-01-2759,Quito,Ecuador
2 ResearchCentreforEnergyResourcesandConsumption(CIRCE),UniversidaddeZaragoza,
CalleMarianoEsquillorGómez,15,50018Zaragoza,Spain;[email protected](G.C.);
[email protected](Al.V.);[email protected](An.V.)
* Correspondence:[email protected];Tel.:[phone]
Received:27November2017;Accepted:3March2018;Published:6March2018
Abstract: LatinAmericahastraditionallybeenarawmaterialsuppliersincecolonialtimes. Inthis
paper,weanalyzemineralexportsfromanexergoecologyperspectivefromtwentycountriesinLatin
American (LA-20). We apply material flow analysis (MFA) principles along with the concept of
theexergyreplacementcost(ERC),whichconsidersbothquantityandthermodynamicqualityof
minerals,reflectingtheirscarcityinthecrust. ERCdeterminestheenergythatwouldberequired
torecovermineralstotheiroriginalconditionsintheminesoncetheyhavebeentotallydispersed
intotheEarth’scrust,withprevailingtechnology. UsingERChashelpedusidentifytheimportance
of certain traded minerals that could be overlooked in a traditional MFA based on a mass basis
only. Ourmethodhasenabledustodeterminemineralbalance,bothinmass(tonnes)andinERC
terms(Mtoe). Usingindicators,bothinmassandERC,wehaveassessedtheself-sufficiencyand
dependencyoftheregion. WehavealsoanalyzedthemineralexportsflowsfromLatinAmericafor
2013.ResultsshowthathalfofthemineralproductionfromLA-20wasmainlyexported.High-quality
minerals,suchas,gold,silver,andaluminumwerelargelyexportedtoChinaandtheUnitedStates.
Extractionofhigh-qualitymineralsalsoimplieshigherlossesofnaturalstockandenvironmental
overburdensintheregion.
Keywords: LatinAmerica;materialflowanalysis;exergyreplacementcost;mineraltrade;mineral
exports;domesticmaterialconsumption
1. Introduction
Sincecolonialtimes,LatinAmericahastraditionallybeenanexporterofrawmaterials[1]. Before
WorldWarI,theregionwasthemainsupplierofprimaryproductsintheworld[2],andwasalso
a significant supplier of primary products to foster the industrial revolution in Western European
countries[3]. Inrecentyears, theregionhasalsobeenakeysupplierofrawmaterialsforChina’s
boomingsociety[4–6]. Nowadays,theregionischaracterizedforitsimportanceintheglobalmarket.
In2014,exportsoffossilfuelsandminingproductsfromSouthandCentralAmericatoAsia,North
America,andEuropeaccountedfor$89,$77,and$37billionUSD,respectively[7].
A useful way to study flows and patterns of resource use across regions is through Material
FlowAnalysis(MFA)[8]. Indeed,MFAoffersacompleteandsystematicdescriptionofaspecified
systemtosupportpolicymakers[9]. Itprovidesdataregardingtheextractionandtradeofmaterials,
henceofferingusefulinformationfortheestablishmentofsustainableschemes[10–14]. Moreover,
thisapproachhasbeenusedtoshowthedependenceofaregiononmineralimports. Tothatend,
Schaffartziketal.[12]analyzedpatternsandtrendsofmaterialsextraction,trade,andconsumption
of177countriesintheworld,whichweregroupedinsixregions,from1950to2010. Theystatedthe
Sustainability2018,10,723;doi:10.3390/su10030723 www.mdpi.com/journal/sustainability
Sustainability2018,10,723 2of18
importanceofLatinAmericaandtheCaribbeanasmetalproducers,especiallyforcopper,silver,tin,
andiron,supplying12%ofworld’smetaldemand. Otherprominentstudieshaveanalyzedmaterial
flowsfocusingonlyonLatinAmerica. Forinstance,country-specificMFAwereundertakenbyVexler
etal. forChile[15],byPerez-RinconforColombia[16],byVallejoforEcuador[17],Tanimotoetal. for
Brazil[4],andWalteretal. forArgentina[18].
Onamulti-countryperspective,in2007areportpublishedbytheUnitedNationsEnvironmental
Programme(UNEP)onmaterialflowsandresourceproductivity, analyzedtencountriesofSouth
AmericaandtheCaribbean: Argentina,PlurinationalStateofBolivia,Brazil,Chile,Colombia,Ecuador,
Guatemala,Mexico,Peru,andtheBolivarianRepublicofVenezuela[19]. Themainconclusionofthis
studywasthatgrowthindemandofresourcesofotherregionscanhaveeffectsonLatinAmerica’s
materialflows. Thus,MFAforLatinAmericaarecrucialinaglobalizedeconomy.
Inanotherstudy,Russietal.[20]analyzedtheconsequencesofneoliberaleconomicreformson
naturalresourcesofChile,Ecuador,Mexico,andPeruthroughMFAfrom1980to2000. Thisstudy
demonstratedthatdomesticmaterialextractionhadincreasedinthesefourcountriesasaconsequence
ofeconomicreforms. Inasimilarway,WestandSchandl[21]analyzedmaterialuseandefficiency
in22countriesinLatinAmericaandtheCaribbean. Materialflowsfrom1970to2008werestudied,
andaremarkableconclusionwasthatthesecountrieswerelessefficientingainingeconomicprofitby
meansofsellingtheirnaturalresources. AsimilarconclusionwasmadeinthestudybyGiljumand
Eisenmenger[22],whichobserved“anunequalenvironmentaldistribution”atgloballevelbetween
the distribution of environmental goods and environmental burdens between the North and the
South. TheNorth,suchastheEuropeanUnion[23],whichismostlyresourcedependentonsouthern
countries,sellshigh-valueproductstotheSouth,whileleavingthenegativeenvironmentalimpacts
thatareassociatedtorawmaterialextractionintheSouth[22].
Itisafactthatminingactivitiescanresultinimportantenvironmentaldamages. Webplatforms,
such as the Environmental Justice Atlas [24] and information by Bottaro and Sola-Alvarez [25],
give an overview of the effects on the environment caused by mining activities in Latin America.
TheObservatoryofminingconflictsinLatinAmerica(OCMAL)reportedinitsdatabase229conflicts,
mostoftheminPeru,Mexico,Chile,andArgentina[26]. Morespecifically,problemsthatarerelated
towaterusageinminingwereanalyzedbyAitkenetal.[27]inthenorthofChile. Himley[28]in
turn,raisesquestionsregardingsustainabledevelopmentandtheroleoflarge-scaleminingindustries
throughastudyinagoldmineinPeru.
Neither environmental damages nor the loss of natural stock caused by mining activities are
reflected in conventional MFA, which are commonly made using tonnage as the unit of measure.
M,atonnage-basedassessmentleavesoutthequalityofcommodities. Toovercomethisissue,theloss
of natural stock can be quantitatively analyzed through an indicator based on the Second Law of
Thermodynamics, called exergy replacement costs (ERC) [29,30]. As it will be explained in the
methodology section, using ERC instead of tonnage we can assign a greater value to scarcer and
difficulttoobtainmineralstherebyavoidingtheproblemof“addingappleswithoranges”. Notethat
thissamestudycouldbedoneonamonetarybasis. Nevertheless,pricesrarelytakeintoaccountthe
physical reality of minerals, such as geological scarcity. They are volatile by nature since they are
subjecttomarketfluctuations[31].
Thus,tohaveanorderofmagnitudeforthelossofnaturalstockinLatinAmericaduetomineral
extraction,andtoidentifywheresuchvaluablemineralsendedup,thispaperundertakesamaterial
flowanalysis(MFA)basedontheSecondLawofThermodynamics. Atotalof20countriesinLatin
Americahavebeenanalyzed:Argentina,Bolivia,Brazil,Chile,Colombia,CostaRica,Cuba,Dominican
Republic,Ecuador,ElSalvador,Guatemala,Honduras,Mexico,Nicaragua,Panama,Paraguay,Peru,
Uruguay,Venezuela,andHaiti(hereafterLA-20). Forthispurpose,themineralbalanceforLA-20was
examined,usingindicatorsthatcanhelpevaluatetheself-sufficiencyordependencyoftheregionand
evaluatingexportsbydestination. Withthemineralbalance,bothinmassandERCterms,mineral
productionfrom1995to2013wasassessedanddifferencesbetweenbothapproacheswereexplored.
Sustainability2018,10,723 3of18
Mineralexportsbydestinationwereexaminedforaparticularyeartoseewhichcountriesbenefitfrom
thenaturalstocklossofLA-20. Tothatend,wehavefollowedtheexergoecologymethodproposed
byValeroetal.[32]andguidelinesofinvestigationspublishedbyCalvoetal.[33–35]andCarmona
et al. [36]. In these studies, the ERC concept was used to develop a MFA for European countries
(EU-28)andforColombiain2011. Alongsidethesestudies,weseektodemonstratethatconsidering
thethermodynamicqualityofmineralsthroughERCwouldfurtherimprovethepotentialofMFA,
especiallywhendealingwithnon-fuelminerals. Thefinalaimistocontributetoadeeperdiscussion
onthesearchforsustainablepathsonmineralproductioninLatinAmerica.
2. Methodology
2.1. ResearchFramework
Exergyhasbeentraditionallyusedtomeasureanyenergysource,andisdefinedastheminimum
amount of work that may be theoretically performed by bringing a system into equilibrium with its
surrounding environment. It is a property of a system-environment combination and is helpful in
recognizingandevaluatingconsumptionofnon-renewableresources,especiallyfuelminerals[37–39].
Theexergycontentoffuelmineralsisassociatedtotheirchemicalcompositionandcanbeapproximated
withnosignificanterrortotheirHighHeatingValue(HHV),whichcanbeobtainedfrom[40].Yet,non-fuel
mineralscannotbeevaluatedusingthissameapproachastheyarenotcombustible.Thisiswhynon-fuel
resourceshavebeentraditionallyassessedthroughtheirchemicalexergycontent.Thelatter,inturn,canbe
obtainedfromtheGibbsfreeenergyofthegivensubstance∆G andthechemicalexergyoftheelements
f,i
thatformthesubstance,asexpressedinEquation(1):
b = ∆G +∑n ×b (1)
chi f,i j,i ch,j
j
whereb isthestandardchemicalexergyoftheelementsn thatcomposesubstancei.Gibbsfreeenergy
chj j,i
indicatesthethermodynamicpotentialavailableforusageuntilasystemreacheschemicalequilibriumat
aconstantpressureandtemperature[41,42].Commonly,thechemicalexergyoftheelementsisusually
takenfromthevaluesobtainedbySzargut[43]andtheGibbsfreeenergycanbeobtainedfromchemical
databases,or,alternatively,estimatedwithdifferentcalculationprocedures[44,45].
This way of assessing the exergy of substances, including mineral resources, has been
used by different authors including Szargut et al. [33,46,47], Ayres [48], or Dewulf et al. [49].
Yet, as demonstrated by Domínguez et al. [50], assessing minerals solely with chemical exergy
disregards important aspects that make minerals valuable. As an example, the chemical exergy
of precious metal gold is 60 kJ/mol, whereas that of aluminum is 796 kJ/mol. In this respect,
exergoecologyhasbeenestablishedfortheevaluationofnaturalresourcesandonedivisionofthis
disciplineisPhysicalGeonomics,whichinvestigateshowtheexergyconceptcanbeappliedtothe
assessment of non-fuel minerals. In addition to the chemical exergy, minerals have an important
physicalfeaturethatmakesthemvaluable,mainlytheirrelativeconcentrationinthecrust. Thefact
ofhavingmineralsconcentratedinminesandnotdispersedthroughoutthecrustrepresentsa“free
bonus” provided by Nature, which allows for significantly reducing the costs that are associated
withmining. Whenminesbecomedepleted,thisfreebonusisreduced,meaningthatmoreenergyis
requiredtoextractthesameamountofmetal. Suchabonuscanbeassimilatedtoahiddenoravoided
costthatcanbequantifiedthroughtheso-calledexergyreplacementcosts(ERC).Thesearedefined
as the exergy costs that would be needed to extract and concentrate a mineral from a completely
dispersedstatetotheconditionsofconcentrationandcompositionfoundinthemineusingprevailing
technology. ERC values are, thus, related to the scarcity degree of a given mineral, which can be
reflectedthroughtheconcentrationexergy(b ),ascalculatedwithEquation(2).
ci
(cid:20) (1−x )(cid:21)
b = −RT0 lnx + i ln(1−x ) (2)
ci i i
x
i
Sustainability2018,10,723 4of18
whereb representstheminimumtheoreticalwork,exergy,whichrequiredtoconcentrateasubstance
ci
ifromanidealmixtureoftwocomponents;x canbeeithertheaverageconcentrationinthemines
i
measureding/g(x )ortheconcentrationintheEarth’scrust(x );Risthegasconstant(8.314J/molK);
m c
and,T0istheabsolutereferencetemperature(298.15K).
Theexergy(∆b )associatedtotheconcentrationofmineralsfromadispersedstateinthecrust
c
tothatinagivenmineraldepositisdeterminedbytheconcentrationexergywhenx =x andwhen
i c
x =x ,thusEquation(3).
i m
∆b (x → x ) = b (x = x )−b (x = x ) (3)
c c m c i c c i m
Sinceexergyonlyreportsminimumvaluesandman-madetechnologyisveryfarremovedfrom
reversibility,weneedtoresorttoexergycosts. Accordingly,theso-calledexergyreplacementcosts(B*)
arecomputedwithEquation(4):
B∗ = k×∆b (x → x ) (4)
c c m
wherevariablekisadimensionlessconstantcalledunitexergycost. Itistheratiobetween: (a)thereal
cumulativeexergyrequiredtoaccomplishtheprocessofconcentratingthemineralfromtheoregrade
x tothecommercialgradex and(b)theminimumthermodynamicexergyrequiredtoaccomplishthe
m r
sameprocess∆b (x → x )[30]. Animplicitassumptioninthemethodologyis,thus,thatthesame
c m r
technologyappliesforconcentratingamineralfromx tox asfromx tox .
m r c m
Theaforementionedmethodologyisusedtocalculatetheexergyreplacementcostsofthemain
mineralcommoditiesthatarecurrentlyusedbyindustryonaglobalbasis. Itshouldbenotedthat
forobtainingtheglobalERCofminerals,itisassumedthateachcommodity(i.e.,copper)isobtained
fromasingletypeofore(i.e., chalcopyrite). Foreachmineral, theaverageglobaloregradeswere
considered(x ),mainlyobtainedfromCoxandSinger[51],aswellastheaverageenergyvaluesof
m
state-of-the-arttechnologiesinminingandbeneficiation. Thedepletedoregrade(x )wasobtained
c
throughamodelofdispersedEarth,calledThanatia[29]. ThanatiacomesfromtheGreekThanatos
that means death. In our perspective, Thanatia is a baseline for the exergy assessment of mineral
resourcesandrepresentsanidealizationoftheplanetwhenallofthefossilfuelshavebeenburnedand
allmineralshavebeentotallydispersedintothecontinentalcrust[29,52]. Thanatia’scrustiscomposed
ofthe300mostabundantmineralsataveragecrustalconcentrations[29]. Onceexergyreplacement
costsofmineralsareobtained(i.e.,forchalcopyrite),thoseoftheelement(i.e.,forCu)arecalculated
throughtheircorrespondingmolecularweights.
Onekeyaspectthatdifferentiatesexergyreplacementcosts(ERC)fromotherthermodynamic
propertiesisthatERCconsidersthescarcitydegreeofthecommoditiesinthecrustandtheenergy
required to extract them. When a mineral is scarcer and its extraction and beneficiation processes
are more difficult, its ERC value becomes higher. This is why, contrarily to what happens when
only chemical exergy is used for the assessment, precious metals, such as gold and silver, exhibit
highervaluesofERCthanmoreabundantones,suchasironorlimestone. HighervaluesofERCthus
representahigherqualityofmineralsandwouldalsomeanahigherlossofthenaturalstockina
regionifthesebecomedepleted.
These values have been taken from Valero et al. [40]. Due to the number of minerals that are
consideredinthecurrentstudy,onlyselectedERCvaluesofmineralshavebeenlistedinTable1.
AlltheERCvaluesofmineralsconsideredinthecurrentstudycanbeseeninAppendixA,buta
completelistofallmineralswiththeircorrespondingERCvaluescanbefoundin[53].
Sustainability2018,10,723 5of18
Table1.MainexergyreplacementcostsforthecurrentstudyinGJpertonneofelement(source:[54]).
MineralOre ERC(GJ/t)
Non-fuelminerals
Gold Nativegold 553,250
Silver Argentite 7371
Zinc Sphalerite 1627
Copper Chalcopyrite 292
Lead Galena 37
Limestone Calcite 3
Phosphaterock Fluorapatite 0.4
Fuelminerals
CrudeOil 46.3
Coal 24.3–31.6
NaturalGas 39.4
Note:1GJ=2.39×10−8Mtoe.
2.2. DataCompilation
With the aforementioned methodology, the mineral balance of LA-20 from 1995 to 2013 was
analyzed,takingintoconsiderationseveralindicatorsthatcanbeusedtoevaluateself-sufficiencyor
dependencyoftheregion. Exportsbydestinationsfor2013werealsoanalyzed. Inallofthecases,
2013wasusedasthelastyearanalyzedasitwasthemostrecentyearforwhichtherewasinformation
availableforallLA-20countries.
A total of 38 non-fuel minerals were considered in this paper: aluminum, antimony, barite,
beryllium,bismuth,cadmium,chromium,cobalt,copper,fluorite,gold,graphite,gypsum,iron,lead,
limestone,lithium,magnesite,manganese,mercury,molybdenum,nickel,niobium,platinumgroup
metals(PGM),phosphaterock,potash,rareearthelements(REE),salt,selenium,silver,tantalum,tin,
titanium,vanadium,wolfram,zinc,andzirconium. Additionally,fossilfuelswereincludedinthe
study(oil,naturalgasandcoal).
The information needed for this study (extraction, imports, and exports) was gathered from
differentdatasourcesforthe20countriesunderstudy. Onlydataregardingbulkmineralproduction,
imports, and exports were included, thus excluding semi-manufactured products, such as steel.
Thismeansthatifacountryextractsironbutexportssteel,onlyironwastakenintoaccountintheMFA.
Assuggestedineconomy-widematerialflowaccounts(EW-MFA)guidelines[55],theprimarysourceof
informationwasnationaldatabasesandnationalagenciesofeachcountry. Brazil’smineralproduction,
imports,andexportsdataweregatheredfromtheDepartamentoNacionaldeProduçãoMineral[56].
ChileanmineralproductionwasobtainedfromServicioNacionaldeGeologíayMinería[57],imports
andexportsfromComisiónChilenadelCobre[58].Production,exports,andimportsofColombiawere
retrievedfromSistemadeInformaciónMineroColombiano[59]. Ecuador’smineralproductionwas
compiledfromAgenciadeRegulaciónyControlMinero[60],whileexportsandimportsinformation
fromBancoCentraldelEcuador[61]. Production,imports,andexportsofPeruwereprovidedbythe
MinisteriodeEnergíayMinas[62]. Itwasnotpossibletocollectdirectdatafromlocalagenciesfor
Argentina,CostaRica,Cuba,DominicanRepublic,ElSalvador,Guatemala,Honduras,Nicaragua,
Panama, Paraguay, Uruguay, and Venezuela. Instead, mineral trade data of these countries were
collected from British Geological Survey database [63], Economic Commission for Latin America
andtheCaribbean(ECLAC)[64]andtheUnitedNationsInternationalTradeStatisticsDatabase(UN
Comtrade)[65]. Thedisaggregationlevelcorrespondingtomineralexportsandimportswasfivedigits
(UNComtradelicense). Toavoiddoubleaccounting,thisdatabaseallowsfortreatingaselectedregion,
inourcase,LA-20,asasingleunit,thereforenottakingintoaccountexportsandimportsbetweeneach
LA-20country. Forcompletinggapsandforcross-checkingpurposes,reportsoftheU.S.Geological
Service[66]werealsoconsulted. DuetothelackofinformationforHaitiin2013,itwasnotpossibleto
Sustainability2018,10,723 6of18
includeitintheassessmentofexportsbydestinationandmaterialflowindicators. Regardingfossil
fuels,allproduction,imports,andexportsvaluesweregatheredfromtheLatinAmericanOrganization
ofEnergy(OLADE)databases[67].
ESRusCtaiinsabeilixtyp 2r0e18s,s 1e0d, x iFnORG PJEpERe rREtVoInEWne ofelement,henceallmineralinformationexpresse6d oif n18m etal
contentwastakenfromthesedatasources. Thisinformationwasthenconvertedintoexergyterms
destination and material flow indicators. Regarding fossil fuels, all production, imports, and exports
bymeansoftheERCanddifferentindicatorswerecalculated. Oneoftheindicatorsthatwasusedin
values were gathered from the Latin American Organization of Energy (OLADE) databases [67].
thestudyiEsRdCo ims eexsptircesmseadt einri aGlJ cpoenr stuonmnpe toiof nele(mDeMntC, )h,ednecefi nalel dmainsetrhael ianmforomuanttioonf epxhpyressicseadl mini mneertaall sthat
arecocnosnutmenet dwianss tiadkeeno nfreomre gthioesne. dHaetan csoeu,rDceMs.C Thisisc ianlfcourmlaatetidona swtahse thseunm coonfvmeritnede rianltso tehxaetrgayr eteprmrosd uced
inthebrye gmioeann(sd oof mthee sEtRicCe axntdra dcitfifoernen=t DinEdi)captlourss wimerpeo cratlscu(Ila)tmedi.n Ounsee oxf pthoer tisnd(Eic)a.toTrhs ethtaetr wmasc ounsesdu min ption
inthisthpea sptuerdyre ifse drosmtoesatpicp maaretenrtiacl ocnonsusummppttiioonn (aDnMdCn)o, tdefifninaeldc aosn tshuem amptoiuonnt (oif. ep.,hgysoiocadl smairneereaxlsc ltuhadte dfor
are consumed inside one region. Hence, DMC is calculated as the sum of minerals that are produced
theanalysis). Goodsarenotconsideredinthisanalysisfortworeasons: first,becauseofimportant
in the region (domestic extraction = DE) plus imports (I) minus exports (E). The term consumption in
information gaps regarding semi-manufactured products exported and imported in the analyzed
this paper refers to apparent consumption and not final consumption (i.e., goods are excluded for the
countries;andsecond,becausethissameapproachwasusedinCalvoetal.[35]forEU-28,andsothe
analysis). Goods are not considered in this analysis for two reasons: first, because of important
resultscanbecompared. TheseindicatorswerecalculatedbothinmassandERC.Subsequently,using
information gaps regarding semi-manufactured products exported and imported in the analyzed
thisincfoournmtraietiso; ann,dd sifefceornedn, tbreacatiuosse othfids soammees atpicperoxatcrha cwtiaosn us(DedE i/n DCaMlvCo )e,ti aml. p[3o5r]t fso(rI E/UD-M28,C a)n,da nsod theex ports
(E/DMreCsu)lwts ecraeno bbet acionmedp.arTehde. Tuhseesfeu linnedsicsaotofrtsh weseerer actailocsuliasttehda btoththe yinc amnaspsr oanvdid EeRinCf.o Srumbasetiqounenatblyo,u tthe
depenudseinngc ythains dinsfeolrfm-sautifofinc,i ednifcfyereonfta rraetigoiso nof[ 3d5o]m. estic extraction (DE/DMC), imports (I/DMC), and
exports (E/DMC) were obtained. The usefulness of these ratios is that they can provide information
3. Resaublotsuta tnhde dAenpeanlydseinscy and self-sufficiency of a region [35].
R3e. sRuelstsulotsf athned sAtunadlyysaisr eseparatedintothreesections. First,theevolutionofmineralproduction
of LA-20 from 1995 to 2013 is analyzed using both mass terms (tonnes) and ERC terms (Mtoe).
Results of the study are separated into three sections. First, the evolution of mineral production
Additionally, Sankey diagrams are used to represent the mineral trade in 2013 of three selected
of LA-20 from 1995 to 2013 is analyzed using both mass terms (tonnes) and ERC terms (Mtoe).
countrAiedsd(iBtioranzaillly,,C Shainlek,eayn ddiaMgreaxmicso a)rbeo uthseidn tmo arespsraensednEt RthCe .mTihneenra,lr atrtaiodse tihna 2t0s1h3o wof tthherede espeleencdteedn cyor
self-sucfofiucniterniecsy (Borfatzhile, Crehgilieo, nanadr eMceaxliccuol)a btoetdh fionr m2a0s1s3 a.nLda EstR,Cth. eThdeens,t rinataiotiso tnhsato sfhtohwe tehxep doerptsenodfemncayt erials
produocre dseilnf-sLuAff-ic2i0enacrye sotfu tdhiee dretgoiohna avree acablectutleartekdn ofowr l2e0d1g3e. Loafswt, htihceh dceosutinntartiieosnsa roef rtehlee geaxtpinorgtsi nofL A-20
theenmviartoenrimalse pnrtoadlubcuerdd ienn LaAs-s2o0c airaet estdudtoietdh teo mhaivnei na gbeitntedru ksntoryw.ledge of which countries are relegating
in LA-20 the environmental burden associated to the mining industry.
3.1. MineralBalance
3.1. Mineral Balance
Figure 1 shows non-fuel mineral production of LA-20 disaggregated by minerals, data was
Figure 1 shows non-fuel mineral production of LA-20 disaggregated by minerals, data was
compiled from USGS statistics [68] and then compared to the information provided by national
compiled from USGS statistics [68] and then compared to the information provided by national
agenciestoensuremaximumcoherenceandcompleteness.
agencies to ensure maximum coherence and completeness.

Figure 1. Non-fuel mineral production in LA-20 from 1995 to 2013 in mass terms expressed in million
Figure1.Non-fuelmineralproductioninLA-20from1995to2013inmasstermsexpressedinmillion
tonnes (left) and in exergy terms expressed in Mtoe (right). Only the minerals that can be seen in the
tonnes(left)andinexergytermsexpressedinMtoe(right).Onlythemineralsthatcanbeseeninthe
figures are shown in the legend.
figuresareshowninthelegend.
Overall, in mass terms, the most extracted minerals in LA-20 from 1995 to 2013, were iron,
Oavluemrainllu,min, smalta, slsimteesrtmonse,, tahned mgyopsstuemx t(raavcetreadgem ofi n1e9r7a, l2s8,i n18L, 1A2-, 2a0ndf r9o mmil1li9o9n5 totnon2es0 1p3e,r wyeearre, iron,
respectively). When these data is translated into loss of natural stock in the region, through the ERC
aluminum, salt, limestone, and gypsum (average of 197, 28, 18, 12, and 9 million tonnes per year,
concept, the highest loss corresponded to aluminum (average value of 413 Mtoe), followed by iron
respectively). When these data is translated into loss of natural stock in the region, through the
(84 Mtoe). In the period of analysis, iron production represented 72% as an average of the total
ERCconcept,thehighestlosscorrespondedtoaluminum(averagevalueof413Mtoe),followedby
production in tonnes, while in Mtoe it represented only 13%. On the opposite side, aluminum, which
Sustainability2018,10,723 7of18
iron(84Mtoe). Intheperiodofanalysis,ironproductionrepresented72%asanaverageofthetotal
productionintonnes,whileinMtoeitrepresentedonly13%. Ontheoppositeside,aluminum,which
Sustainability 2018, 10, x FOR PEER REVIEW 7 of 18
onlyrepresented10%ofthetotalproductionintonnes,represented66%inERC.Hence,thelossof
naturalosntloyc rkepinresLeAnt-e2d0 1w0%as omf tahien tloytacla pursoedducbtiyona liunm toinnnuems, rreaptrheesrenttheadn 66ir%o nin. TERhCe.i mHepnocret, atnhec eloosfs toafk ing
intoconnsaitdueraral tsitoonckq iuna LliAty-2a0n wdans omtaoinnllyy cqauuasendti btyy oaflunmoinn-ufmue rlamthienre trhaalns iisrorne.v Tehaele idmwpoirtthanthceis ocfo tmakpinagr ison.
Thientcoo mcopnlseitdeermatiinoenr aqlubaaliltayn caendd isnaogtg roenglya teqduabnytimty inoef ranlofno-rfuLeAl -m20inienra2ls0 1i3s inremveaaslesda nwditEhR tChitse rms
canbesceoemnpianritshone.A ppendixsBandC.Analyzingthesedataindetail,itcanbeobservedthatthemost
The complete mineral balance disaggregated by mineral for LA-20 in 2013 in mass and ERC
extractedfuelmineralsinthatyearwerecrudeoilandnaturalgas,withashareof63%and23%of
terms can be seen in the Appendixes B and C. Analyzing these data in detail, it can be observed that
thetotalfossilfuels,respectively. Regardingnon-fuelminerals,iron,aluminum,andsaltwerethe
the most extracted fuel minerals in that year were crude oil and natural gas, with a share of 63% and
mostproducedinmassterms(69%,9%,and6%,respectively). Whenlookingatconsumptiondata,
23% of the total fossil fuels, respectively. Regarding non-fuel minerals, iron, aluminum, and salt were
crudeothile, amnodst npartoudruacledg aisn wmearsse tlearrmgse l(y69c%o,n 9s%um, aendd w6%it, hrienspLecAti-v2e0ly,)a. nWdhreeng laorodkiinngg anto cno-nfsuuemlpmtiionne rals,
iron,aludamtain, ucrmud,eli moiel,s taonnde ,naantudrasla lgtaws ewreerme olasrtgleylyc ocnosnusmumeeddi nwteitrhnina llLyA. T-2h0e, acansde sreogfalridminegs tnoonne-faunedl salt
canbeemaisnielyraelsx, pilraoinn, eadluamsiunsuuma,l lyliminedstuosnter,i aalnmd isnaelrt awlse,rwe hmicohsthlya vcoenlsouwmeerdp rinicteersntahllayn. oTthhee rcamseest aolfl icor
non-melitmalelisctomnei naenrda lssa,lta rceanc obne seuamsileyd exinptlaeirnneadl lays, ruastuhaellryt hinadnusetxripaol rmteindetroalso,t whehriccho huanvter ileosw. er prices
than other metallic or non-metallic minerals, are consumed internally, rather than exported to other
Asstatedbefore,mineraltradecanberepresentedusingSankeydiagrams,witharrowsshowing
countries.
theproduction,imports,exports,anddomesticconsumptionproportionaltoflowquantities. Asit
As stated before, mineral trade can be represented using Sankey diagrams, with arrows showing
waspreviouslymentioned,domesticconsumptionreferredtoapparentandnotfinalconsumption.
the production, imports, exports, and domestic consumption proportional to flow quantities. As it
Therefore,andasopposedtoconventionalEW-MFA,semi-manufacturedproducts(eitherenteringor
was previously mentioned, domestic consumption referred to apparent and not final consumption.
leavingTthheereafnorael,y aznedd assy ostpepmos)ewd etore connovtetnatkioennailn EtWoa-MccFoAu,n ste.mIni-mcoannvufeancttiuorneda lpEroWd-uMctFs A(e,itthheer ceonmterpinogsi tion
of mosotrt rlaedaveidngg othoed saniaslyazsesde sssyesdteums)i nwgerteh enomt atiankemn aitnetori aalcccooumntp. oInne ncotnovrentthioenmal aEinWr-MawFAm, athtee rials
usedincothmepopsriotidonu cotfi omno.stO trnadthede gcooondtrsa irsy a,sisnesoseudr uasninagly tshies mifafionr meaxtaemriapl lceomiropnonwenats our stheed minatienr rnaawll yto
producmesatteereila,las nudsetdh iisn inthteu prnro,dwuactsioenx.p Oonrt ethde, tchoentcroarryre, sipn oonudr inangailyrosins wif afosrc oexnasmidpelree diroans waacso musmedo dity
internally to produce steel, and this in turn, was exported, the corresponding iron was considered as
consumedinternally. Thisiswhy,accordingtotheEW-MFAdefinitions,ourresultsareonlypartial
a commodity consumed internally. This is why, according to the EW-MFA definitions, our results are
whenanalyzingimportsandexportsasweonlyconsiderbulkcommodities.
only partial when analyzing imports and exports as we only consider bulk commodities.
Threecountrieshavebeenselectedforsuchpurposes,Brazil,Chile,andMexico(Figure2). These
Three countries have been selected for such purposes, Brazil, Chile, and Mexico (Figure 2). These
countrieshavebeenchosenasanexampleastheyapproximatelyrepresent65%ofthetotalmineral
countries have been chosen as an example as they approximately represent 65% of the total mineral
tradeintrLaAde- 2i0n. ALAll-o20f.t hAellm oifn ethrae lmcoinmemralo dcoitmiems(o3d8it)iaeslo (n3g8)w ailtohnng awtuitrha lngaatsu,roali l,gaans,d ociol,a alnadre croeaplr easree nted
inthedrieapgrreasemn,tebdu itnt thhee ldeigagenradmo, nbulyt tshheo lwegsenthdo osnelyth sahtowcasn thboesee athsailty casne ebne ienastihlye sfieegnu irne .the figure.

Figure 2. Sankey diagrams for Brazil, Chile, and Mexico for 2013 expressed in million tonnes (upper
Figure2.SankeydiagramsforBrazil,Chile,andMexicofor2013expressedinmilliontonnes(upper
row) and in Mtoe (lower row) for selected substances.
row)andinMtoe(lowerrow)forselectedsubstances.
In some countries, when calculating the domestic material consumption, negative values can be
Inosbotmaineedco fuonr tcreiretsa,inw choemnmcoadlcituielas,t isnugcht haes dgoolmd,e ssitlivcerm, laetaedr,i aolr czoinncs,u ams petxipoonr,tsn aergea thiivgehevra tlhuaens can
be obtapinroedducftoiornc earntda iinmpcoormtsm coomdbitinieesd,. sIullecghala asngdo alrdti,ssainlavle mr,inleinagd ,aroer az sienrcio,uass perxopbolermts ina rteheh riegghieorn,t han
productionandimportscombined. Illegalandartisanalminingareaseriousproblemintheregion,
Sustainability2018,10,723 8of18
especiallyinthecaseofpreciousmetals,suchasgold[69–72]. In2013,itwasestimatedthat158tonnes
ofgoldwereproducedillegally,accountingfor$6.9billionUSD.Countrieswithhigherillegalgold
production rates in that year were: Venezuela, Colombia, and Ecuador [72]. Negative values of
domesticconsumptioncanalsobeexplainedbythelackofreporteddatabyofficialauthoritiesand
variationinstocksthatarenotshownonmineralstatistics. Thedifferencebetweeninputandoutput
flowswasrepresentedinthediagramas“imbalance”. Still,thisimbalanceonaverageisquitelow
whencomparedtotheremainingflows.
InBrazilin2013,inmassterms,themostproducedandexportedcommoditywasiron,witha
shareof57%ofthetotaldomesticproductionand85%ofthetotalexports,respectively.Whenanalyzing
that sameinformationapplying theERC concept, themain commoditycontributing tothe lossof
naturalstockwasaluminum,withashareof66%. Inamerelytonnageperspectivethereisalmost
nodifferencebetweentotalexportsandtotaldomesticconsumption. Ontheotherhand,intermsof
quality,consumptionofhigher-qualityminerals,suchasaluminum,potash,andcrudeoil,wasthree
timeshigherthanexports.
AsforChile,thecountryimportedlargeamountsoffossilfuelsandprincipallyproducedcopper,
iron,andsalt. Chileisaworldleaderincopperproduction,andin2013copperextractedrepresented
one-thirdoftheglobalcopperproduction[73]. WhentransformingthisinformationusingERC,itcan
beseenthatcopperplaysamajorroleinexportsasmoreemphasisisplacedonitsphysicalquality:
itrepresentsmorethan90%ofthetotalexports. Totalexportsintonnesrepresentafifthofthetotal
outputs(exportsplusdomesticconsumption)butwhenexpressedinERCtheyonlyaccounthalf.
AsforMexico,themostnotabledifferencewiththeothertwocountriesisthatitmainlyproduces
fossilfuels,alongwithsmallamountsofiron.Itisalsonoteworthythattherewasnomajordependency
ontheexternalsupplyforinternalconsumptionofminerals,asonlysmallamountsofgasandcoalwere
imported. Inmassterms,Mexico’sconsumptionwasmainlydominatedbynaturalgasandcrudeoil
andwasoneorderofmagnitudehigherthanexports. InERCterms,consumptionwasapproximately
twotimeshigherthanexports. Apossibleexplanationforthisvalueisthehighfossil-fuelconsumption
inMexico,as,forinstance,in2014morethan59%ofthetotalfinalenergyconsumptioncamefrom
fossilfuels[74].
3.2. MassandERCIndicators
As stated before, different ratios were calculated: DE/DMC, I/DMC, and E/DMC,
each considering domestic extraction, imports, and exports, respectively, when compared to
DMC. These ratios only include material trade of the fossil fuels and non-fuel minerals listed in
previoussections.
AlloftheratioswerecalculatedbothintonnesandinMtoeforLA-20for2013(Table2). Absolute
resultsarenotcomparablebetweenbothunitsofmeasure. Yetthatisnotthecasewhenweassess
ratios,suchasDE/DMC,I/DMC,orE/DMC.
Table2.ComparisonbetweenLA-20andEU-28.
LA-20(2013Data) EU-28(2011Data)
DE/DMC I/DMC E/DMC DE/DMC I/DMC E/DMC
Non-fuelminerals
Mass 1.88 0.11 1.00 0.79 0.30 0.09
ERC 1.50 0.16 0.66 0.45 0.94 0.40
Fossilfuels
Mass 1.36 0.24 0.59 0.52 0.62 0.13
ERC 1.35 0.22 0.57 0.41 0.76 0.17
WhenlookingatDE/DMCratiosofnon-fuelminerals,itisclearthatLA-20in2013produced
more minerals than those it consumed internally. Imports were significantly lower than domestic
consumptionandexportswerealsosignificant,whichisconsistentwiththeimagethatLA-20has
Sustainability2018,10,723 9of18
ofbeinganetexporterterritory. InthecaseofDE/DMCratio,thevalueinmassishigherthanin
ERC.Theexplanationrelaysontheweightofiron,averyabundantelementthathasalowERCvalue
(18GJ/t). Whenexpressedintonnesironaccountsfor68%ofthetotalLA-20mineralproductionbut
inERCthisvalueisonlyfor13%. Onthecontrary,fortheI/DMCratio,thevalueinERCishigher
thaninmass,meaningthatthemineralsimportedhavehigherERCvaluesandarethereforemore
scarce,suchisthecaseofpotassium(665GJ/t),whichaccountsfor79%ofthetotalimportsinERC,
butonly19%inmass.
Theregionproducedmorefossilfuelsthanthoseitconsumedinternally;analyzingtheDE/DMC
andE/DMC,itcanbeseenthatalargeamountofthefossilfuelsproducedintheregionwereexported.
NohighvariationbetweenratiosofDE/DMC,I/DMC,andE/DMCoffossilfuelscanbeappreciated
whencomparingtheresultsinmassandERC.Thisisrelatedtothehighimportanceofoilandgasin
domesticextraction,as,asseenbefore,bothrepresentedapproximately85%ofthetotalfossilfuels
extractedinLA-20in2013. Ahighervariationwouldbeperceivedifcoalwouldplayamoreimportant
role. ThisisbecausecoalhasacomparativelylowerHHVthanoilornaturalgas.
Calvo et al. [35] applied MFA with an exergoecology approach for twenty-eight European
countries (EU-28) using 2011 as the reference year. Although the latter and current study differs
bytwoyears,acomparisonamongtheindicatorsobtainedinthisstudywillgiveusanindicationof
mineralsufficiencyanddependencyforbothregions.
Ingeneral, thiscomparisonclearlyshowsamarkedlydifferencebetweenbothregions, while
DE/DMCishigherthan1forLA-20(i.e.,exportsarelargerthanimports),statingtherelevanceof
domesticextractionandexports,fortheEU-28thisvalueisconsiderablylower. Thisisunderstandable
as EU-28 relies on minerals imports rather than on domestic extraction, therefore shifting the
environmentalburdenofmineralextractiontootherterritories.
Asexpected,non-fuelmineralvaluesoftheratioI/DMCforLA-20wereconsiderablylowerthan
thoseforEU-28. ThisrevealsthatEU-28hadtorelyonimportingmaterialstomeetitsinternalneeds,
while,inLA-20,domesticextractionwassufficienttocovermostofitsinternaldemand. Inaddition,
the E/DMC ratio was higher for LA-20 than for EU-28, reflecting the importance of LA-20 as an
exporterregion.
Contrary to what happens in EU-28, which in 2011 was extremely dependent on fossil fuels,
in LA-20 the import to DMC ratio was considerably lower and for the case of the exports ratio, it
reflectedthefossilfueltradethattakesplaceintheregion.
RatiosofDE/DMC,I/DMC,andE/DMC,calculatedinERCtermsonly,foreverycountry,except
for Haiti due to a lack of data, are shown in Table 3. It is noteworthy that DMC values for Costa
RicaandElSalvadoraretheonlyoneswithnegativefigures. Thisisbecause,asitcanbeseeninthe
annexes,exportvaluesforthesecountriesarehigherthanproductionandimports. Thelackofmineral
productionofficialdata,whichcanbeincompleteorpresentgaps,canleadtolowervaluesthatdo
notreflecttherealityofthecountry. ThisisevenmorenotoriousinERCthaninmassterms,because
scarcermineralshaveahigherweight.
Table3. Ratiosofdomesticextraction(DE/DMC),imports(I/DMC),andexports(E/DMC)over
domesticmaterialconsumptionforeachcountryinexergyreplacementcost(ERC)termsforfossilfuels
andnon-fuelmineralsin2013.
Country DMC(Mtoe) DE/DMC I/DMC E/DMC
Argentina 73.90 1.07 0.16 0.23
Bolivia 15.22 2.29 0.00 1.29
Brazil 669.62 1.16 0.21 0.37
Chile 63.37 1.38 0.33 0.71
Colombia 37.52 3.27 0.05 2.32
CostaRica −6.64 0.00 −0.22 −1.22
Cuba 10.66 0.50 0.50 0.00
DominicanRepublic 16.67 0.91 0.17 0.08
Sustainability2018,10,723 10of18
Table3.Cont.
Country DMC(Mtoe) DE/DMC I/DMC E/DMC
Ecuador 10.71 2.91 0.00 1.91
ElSalvador −1.97 −0.46 −0.15 −1.61
Guatemala 0.11 1.00 0.00 0.00
Honduras 1.13 0.94 0.06 0.00
Mexico 148.05 1.59 0.18 0.78
Sustainability 2018, 10, x FOR PEER REVIEW 10 of 18
Nicaragua 0.71 0.18 1.00 0.18
Panama 0.02 2.16 0.15 1.31
Guatemala 0.11 1.00 0.00 0.00
Paraguay 0.07 0.43 0.57 0.00
PeruHonduras 28.87 1.13 2.920.94 00.0.168 0.00 2.09
UruguayMexico 2.22 148.05 0.061.59 00.1.986 0.78 0.02
VenezueNlaicaragua 113.66 0.71 1.940.18 1.00.002 0.18 0.95
AverageLAP-2a0nama 62.31 0.02 1.432.16 0.01.159 1.31 0.62
Paraguay 0.07 0.43 0.57 0.00
Peru 28.87 2.92 0.18 2.09
CountrieswitharatioDE/DMChigherthan1in2013were: Colombia,Peru,Ecuador,Bolivia,
Uruguay 2.22 0.06 0.96 0.02
Panama, Venezuela, MexicVoen,eCzuheillae , Brazil,1a1n3.d66 Argent1i.n94a . Col0o.0m2 bia, 0E.9c5u ador, and Peru in 2013
producedthreetimesmoArevefruaegle aLnAd-20n on-fuel62m.3i1neralsth1a.4n3their0n.1a9tional0c.6o2n sumption.
ThisclassificationalsoshowstheimportanceofperformingtheanalysisusingERC,since,until
Countries with a ratio DE/DMC higher than 1 in 2013 were: Colombia, Peru, Ecuador, Bolivia,
now,inamassbasisanalysis,onlyafewcountries,suchas,Brazil,Venezuela,Mexico,andChile,were
Panama, Venezuela, Mexico, Chile, Brazil, and Argentina. Colombia, Ecuador, and Peru in 2013
consideredpraosduthceed mthoreset tsimigens imfiocraen futepl raondd unocne-rfsueiln mtihneerraelsg tihoann tbheecira nuastieonoafl tchonesiurmmpitnioinn. gandoiltradition.
This classification also shows the importance of performing the analysis using ERC, since, until
3.3. Exportnsobwy, iDn ae smtiansas tbiaosnis analysis, only a few countries, such as, Brazil, Venezuela, Mexico, and Chile, were
considered as the most significant producers in the region because of their mining and oil tradition.
Inthissection,thedestinationsofthenon-fuelmineralsfromLatinAmericawerestudied,not
analyzing3o.3n. lEyxpqourtas nbyti Dtieessti,naatsioont herstudiespreviouslydid[12,19–22,75],butconsideringthatminerals
aremorevaluaInb tlheisf rsoecmtioan,q thuea dlietsytinpaotiionnts ooff tvhiee wnonw-fuitehl mthineeEraRlsC froamp pLraotianc Ahm. erica were studied, not
Althoaungalhyzainllg 3o8nlyn qouna-nfutiteielsm, asin oethrearl sstupdrieevs pioreuvsiolyusmly ednidt i[o12n,1e9d–2b2e,7f5o],r beuwt ceornesidcoerninsgid thearte mdinineratlhs eanalysis,
are more valuable from a quality point of view with the ERC approach.
inthegraphsonlythosethatcanbeseenappearonthelegend. Thesegraphswerebasedondatafrom
Although all 38 non-fuel minerals previously mentioned before were considered in the analysis,
UNComtrade[65]. Asexplainedbefore,thisdatabaseallowsforavoidingdoubleaccounting,being
in the graphs only those that can be seen appear on the legend. These graphs were based on data
abletoelimfroinma UteNfl Coowmstrbadeetw [6e5e].n ALs Aex-p2la0inceodu bnetfroirees, tahnisd daotnablyasea nalalolywzsi fnogr atvroaiddeinbg edtowubeleen acLcoAu-n2t0inag,n dtherest
oftheworbldei.ng able to eliminate flows between LA-20 countries and only analyzing trade between LA-20 and
the rest of the world.
Themainexportedmineralswerealuminum,iron,zinc,copper,silver,andgold(139,134,117,58,32,
The main exported minerals were aluminum, iron, zinc, copper, silver, and gold (139, 134, 117,
and23Mtoe,respectively). AsitcanbeseeninFigure3,approximatelyonequarterofalltheminerals
58, 32, and 23 Mtoe, respectively). As it can be seen in Figure 3, approximately one quarter of all the
producedmininLeAral-s2 p0reondudceedd iinn LNAo-2r0t henAdemd einr iNcao,rtmh Aaimnelyricgao, minagintlyo gtohiengU ton ittheed USntitaetde sS,tawtehs,i lwehtihlee three stwentto
otherterritroersite ws.enTth tios sohthaerre tecrarnitobreiesu. nTdheisr ssthoaored cbane cbaeu usendperrostxoiomd ibtyeciasuasek peryoxfiamcittoyr iisn am keiny efraacltotrr aind eandalso
mineral trade and also because some companies that own mines in LA-20 have processing plants in
becausesomecompaniesthatownminesinLA-20haveprocessingplantsinotherpartsoftheworld.
other parts of the world.

Figure 3. Non-fuel minerals exported by destination in ERC terms (Mtoe) for 2013. Due to the scale,
Figure3.Non-fuelmineralsexportedbydestinationinERCterms(Mtoe)for2013.Duetothescale,
some minerals are not included in the legend.
somemineralsarenotincludedinthelegend.