Incorporating unit manufacturing process models into life cycle assessment workflows
William Z. Bernstein, Cesar D. Tamayo, David Lechevalier, Michael Brundage
Life cycle assessment (LCA) carries significant uncertainties and imprecision due to a number of factors, including the framework's linearity assumptions and the wide use of aggregate unit processes in practice. The goal of this work is to exploit the unit manufacturing process (UMP) information model (ASTM E3012-16), to enable parametric environmental analysis of manufacturing systems without disrupting the traditional LCA workflow. The UMP model allows for the consistent recording and exchanging of both physics-based and data-driven models, while labeling the analytical expressions with meta-data that provides domain-specific context, e.g. control parameters and machine conditions. In practice, when manufacturing-oriented LCAs are conducted, practitioners develop their own parametric models from scratch, that are often difficult to reproduce and exchange. Introducing a consistent representation of manufacturing process models helps address this challenge. In this paper, we present a formal mapping of an extension of the ASTM E3012 data model and the ecoSpold2 data model. We then demonstrate the utility of this mapping by (1) generating LCI data from an example UMP model representing a vertical milling process and (2) linking the results with an existing ecoinvent database. To show value, we use the Brightway2 framework to process the LCI data and complete a hypothetical LCA. We conclude by comparing LCA results generated from the parametric milling UMP model against LCA results of a similar milling unit process model from a commercial database. This work is a critical step for merging crowdsourcing efforts related to process modelling, such as CO2PE!, the UMP repository, and UPLCI, with open-source software frameworks used for LCA. Incorporating these reusable abstractions of manufacturing processes that can be instantiated based on a particular manufacturing scenario will improve the reproducibility, re-usability, validity, and accuracy of LCA studies.
, Tamayo, C.
, Lechevalier, D.
and Brundage, M.
Incorporating unit manufacturing process models into life cycle assessment workflows, 26th CIRP Conference on Life Cycle Engineering, West Lafayette, IN, US, [online], https://doi.org/10.1016/j.procir.2019.01.019, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=926672
(Accessed June 6, 2023)