Preliminary environmental impact assessment of plant-based oils as fossil-based bitumen alternatives based on Dutch Environmental Cost Indicator (ECI) scoring method

Abstract

This study serves as a preliminary environmental impact assessment of 10 plant-based oils to substitute fossil-based bitumen used in road construction in the Netherlands using life cycle assessment based on EN 15804 +A1 and the CML midpoint impact category method, where the outcome is monetized using the environmental cost indicator (ECI) score governing in the Netherlands. Inventories of the products are obtained from the combination of available databases (EcoInvent and Agri Footprint 5) and existing research papers. The outcome shows that excluding the biogenic carbon dioxide storage capacity in the bio-based feedstocks causes their ECI scores per 1 ton of material as the functional unit to be higher than the fossil-based bitumen, with the exception of used cooking oil, when compared with bitumen from the EcoInvent database (€52 vs €94.1/ ton). Including biogenic carbon storage leads to the materials cooking oil, tall oil pitch and rosin scoring lower than bitumen (-€95.4 and -€91.2/ton). The total scores are dominated by the human toxicity, marine aquatic eco-toxicity, and global warming potential impact categories. Thus, the feedstocks with the lowest total ECI scores are used cooking oil, tall oil pitch, and tall oil rosin.