D7.1 Preliminary LCA

This document corresponds to the technical report “Preliminary LCA” (Deliverable 7.1) and it presents the results of the preliminary Life Cycle Assessment (LCA) of the Flexby technology, conducted by GD with the support of the project consortium. The study follows the ISO 14040/44 standards and includes all key LCA components, from goal and scope definition to life cycle inventory and impact assessment. A sensitivity analysis was also carried out to explore alternative scenarios, alongside a proposal for future work toward the complete cradle-to-grave LCA of the Flexby system, scheduled for Month 48.

Several coordination meetings were held with project partners to define the Flexby product system and collect relevant process data. FRIMA contributed with information on the design and energy requirements of the microwave pyrolysis reactor. CSIC contributed with experimental data on conventional slow and flash pyrolysis product yields and energy inputs for different feedstock scenarios, as well as insights on biochar activation. PMI provided simulation outputs and energy and mass balances from process modelling in Aspen Plus and HYSYS. IDE offered insights on coordination with partners and potential process optimization. A4F supplied data related to microalgae cultivation, while US provided data on the upgrading of both liquid and gaseous pyrolysis fractions into final fuel and H2-rich gas products. These collaborative efforts ensured data consistency and alignment across the LCA framework.

To ensure methodological robustness and comparability, GD also performed a state-of-the-art review of existing LCA studies related to pyrolysis-based and biomass-to-biofuel systems. This review helped address common challenges and informed key modelling decisions.

The resulting LCA models were built in openLCA, focusing on two feedstocks: Feedstock 2 (microalgae-based wastewater residues) and Feedstock 5 (dairy-based oily sludge). Multiple process scenarios were simulated to assess the environmental performance of the Flexby system against conventional pyrolysis technologies. Environmental impacts were calculated using the Environmental Footprint (EF) 3.1 method, with a focus on identifying key hotspots and understanding the relative sustainability of the Flexby approach.