Availability and Environmental Performance of Wood for a Second-Generation Biorefinery

Abstract

The current global climate change, the 2030 Agenda, and the planetary boundaries have driven new development strategies, such as the circular economy, bioeconomy, and biorefineries. In this framework, this study analyzes the potential availability and sustainability of the wood supply chain for a small-scale biorefinery aiming at producing 280–300 L of bioethanol per ton of dry biomass, consuming 30,000 t of dry biomass per year harvested in a 50 km radius. This wood production goal was assessed from Eucalyptus grandis stands planted for solid wood in northeastern Uruguay. Moreover, to understand the environmental performance of this biomass supply chain, the energy return on investment (EROI), carbon footprint (CF), and potential soil erosion were also assessed. The results showed that the potential wood production would supply an average of 81,800 t of dry mass per year, maintaining the soil erosion below the upper threshold recommended, an EROI of 2.3, and annual CF of 1.22 kg CO2−eq m−3 (2.6 g CO2−eq MJ−1). Combined with the environmental performance of the bioethanol biorefinery facility, these results would show acceptable values of sustainability according to EU Directive 2009/28/ec because the bioethanol CF becomes 1.7% of this petrol’s CF.

Valorization of residual lignocellulosic biomass in South America: a review

“…Uruguay is characterized by the use of forest residues, due to the large number of hectares with trees to deforest. However, in some researches, it was found that the utilization of RLB is being chosen; for example, Rachid-Casnati et al ( 2021 ) established the possibility of implementing a biorefinery, in which between 280 and 300 L of ethanol/t of Eucalyptus biomass ( Eucalyptus grandis ) would be obtained. Other authors, such as Guigou et al ( 2019 ) performed an intensive pre-treatment of eucalyptus sawdust: some samples were initially treated with autohydrolysis at 170 °C and others with mechanical refining at 3000 rpm followed by Kraft pulping at 155 °C (3.4% alkaline loading).…”