Analysis of optimal supply chain networks for olive tree prunings from grove to biorefinery: A use case in Andalusia

Olive tree prunings (OTP), traditionally burned in the field and associated with pollutant emissions, represent a largely underutilised renewable resource in olive-growing regions. This study presents an integrated GIS–MILP methodology to quantify how supply chain design influences OTP mobilisation for plastics-sector intermediates in Andalusia (Spain). Unlike previous GIS-based studies, the approach enables a regional-scale comparison of centralised and decentralised logistics configurations, accounting for harvest, chipping, storage, natural drying, and transport. The results indicate that decentralised systems outperform centralised ones by reducing transport distances and better matching the fragmented spatial distribution of OTP. In the centralised scenario, mobilisation costs reach 143€ t -1 with transport of fresh woodchips accounting for 60% of total mobilisation costs. The most cost-effective option for 1 refinery is the combination with 10 smaller storages, cutting cost to 124 €·t⁻¹ (−13%) by moving dried woodchips efficiently to the refinery. The analyses provide insights to guide the development of regionally targeted bioeconomy and circular-economy policies and strategies by identifying efficient, scalable logistics configurations for agricultural residue valorisation.