Environmental analysis of a lignocellulosic-based biorefinery producing bioethanol and high-added value chemicals

Abstract

Lignocellulosic-based biorefineries for co-production of bioethanol and high added-value products are continuously gaining research interest. In this study, life cycle assessment (LCA) was applied to evaluate the environmental impacts of bioethanol and biochemicals co-production from a Phalaris aquatica L.-based biorefinery located in Greece. This LCA approach assesses the greenhouse gas (GHG) emissions and energy efficiency, considering the lignocellulosic biomass production chain and its conversion steps in the biorefinery for bioethanol and succinic acid production. Three scenarios were developed to determine the environmental characteristics of the biorefinery accounting the plantation characteristics and its biomass yields. Based on the results, the favorable environmental characteristics of the examined biorefinery system were identified. The estimated GHG and energy intensity varied depending on the scenarios studied, thus highlighting regional biomass yields and the impacts of agricultural inputs. Additionally, the energy emissions were found to be the top contributor to the GHG emissions, related to the Greek electricity grid mix. The sensitivity analysis showed that the electricity network can affect the results, hence highlighting the importance of process energy supply. Consequently, it is evident that dedicated perennial herbaceous energy crop appears to be a promising biomass resource towards sustainable biorefineries systems, maximizing GHG emissions reduction.