Fully dynamic carbon footprint of circular biobased systems: A framework with temporal life cycle inventory database (DyPLCA) tailored for forestry and wood products cascades

Global concerns about climate change and its impacts induced by greenhouse gas emissions and processes make it crucial to understand its evolution over time. This is particularly relevant for biobased systems, which take up CO2 during biomass growth, of which a part remains stored during the life cycle of products (considering possible recycling, reuse etc.), and there is an eventual release at the final end of life (e.g. via incineration). However, in the field of life cycle assessment (LCA) and carbon footprint analysis, a static view is still the dominant approach. Few studies have considered dynamic effects, and if so, only by taking into account time differentiation for the foreground system. Therefore, it is only recently that a fully dynamic LCA has been applied (in this case, dynamic only implies temporal differentiation), in particular through the dynamic process based
LCA (DyPLCA) framework, tool and related temporal database. Yet, there are several aspects needing improvement, A framework has been developed to tackle these gaps, as specified in the next section.

First, the DyPLCA temporal database is a collection of temporal data for all ecoinvent 3.2 processes. Currently, ecoinvent 3.9 is available and contains updated information and new processes. Hence, a straightforward improvement we have done for this framework is the update of the DyPLCA database by LIST in the CALIMERO and LCA4BIO projects.

Second, in the respective DyPLCA database, the temporal flows of forestry systems, especially greenhouse gases, have been considered in a simplistic manner. Emission amounts and their temporal distributions are improved based on the outcomes of a flexible parametric model for a balanced account of forest carbon fluxes in LCA.

A third gap relates to the need to update the climate change impact assessment. INSA Toulouse has developed an advanced tool that already covers different types of effects over time and is compatible with DyPLCA outcomes. This tool and its dataset will be updated.

The final and fourth gap of concern is the limited tailored loop modelling for wood cascading systems in ecoinvent and DyPLCA. This is ameliorated by systematically incorporation useage processes with their durations, the possiblity to adapt number of loops and the handling of recycling/reuse.

An application to two cases of the CALIMERO project is envisioned: (1) one on laminated strand lumber (LSL) & (2) the Swedish pulp and paper sector.