title: An improved calculation of the exergy of natural resources for exergetic life cycle assessment (ELCA).
abstract: The focus in environmental research is shifting from emission abatement to critical process analysis, including assessment of resource consumption. The exergy theory offers a thermodynamic methodology to account for the consumption of natural resources. However, exergy data on mineral resources available in the literature are inadequate to apply to exergetic life cycle analysis, due to incompleteness, inconsistencies, and a dated thermochemical basis. An uncertainty assessment of the data has to be performed as well. In this work, three recent thermochemical databases were applied to evaluate the chemical exergy of 85 elements and 73 minerals, 21 of which had not yet been quantified in the literature. The process required the choice of a new reference species for aluminum. Muscovite was selected, giving rise to a chemical exergy of 809.4 kJ/mol for aluminum. The theory proved to be robust for the exergy of chemical elements, as exergy values differing by 1.2% on average from most recent literature were found. On the contrary, the exergy values for minerals differed by factors up to 14 from literature values, due to the application of recent thermochemical values and consistently selected reference species. The consistent dataset of this work will enable straightforward resource intake evaluation through an exergetic life cycle assessment.
authors.affiliation: Research Group EnVOC, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium.
authors.forename: Bram
authors.initials: B
authors.lastname: De Meester
authors.forename: Jo
authors.initials: J
authors.lastname: Dewulf
authors.forename: Arnold
authors.initials: A
authors.lastname: Janssens
authors.forename: Herman
authors.initials: H
authors.lastname: Van Langenhove
mesh_terms: D000535:Aluminum / Q000737:chemistry; D055598:Chemical Phenomena; D002621:Chemistry; D003247:Conservation of Natural Resources; D004463:Ecology; D004777:Environment; D004784:Environmental Monitoring / Q000379:methods*; D005069:Evaluation Studies as Topic; D005308:Fertilizers; D006358:Hot Temperature; D015233:Models, Statistical; D012016:Reference Values; D013696:Temperature; D013816:Thermodynamics
chemical_list: D005308:Fertilizers; D000535:Aluminum