Economic value and environmental impact analysis of lignocellulosic ethanol production: assessment of different pretreatment processes

Abstract

Second generation bioethanol represents an interesting alternative for liquid fuels in times of increased concerns over global warming and energy security. However, the recalcitrant structure of lignocellulosic biomass feedstock, makes necessary a pretreatment process to increase the conversion of sugars. Diluted acid (DA), Liquid hot water (LHW), Steam explosion (SE), Ammonia fiber explosion (AFEX) and Organosolv (OS) pretreatment are assessed using a combined economic value and environmental impact (EVEI) analysis under a full biorefinery setup in order to assess the best pretreatment process from a techno-economic-environmental point of view. Five process areas were identified within each process considered: pretreatment stage, conversion stage, product purification and separation stage, water treatment stage, and co-generation stage. A process simulation software was used to consider material and energy balances of the biorefineries with different pretreatment processes and to optimize the separation and purification processes (e.g. distillation columns). For the considered biomass and scenarios, all processes resulted in positive gains in terms of economic feasibility and carbon dioxide emissions. In particular, Dilute Acid can be considered the best pretreatment process to produce lignocellulosic bioethanol thanks to the best techno-economicenvironmental performences , with the largest economic and environmental margins with 39.2 M$/year and 83.9 kt CO2/year respectively.

Process Simulation and Environmental Aspects of Dimethyl Ether Production from Digestate-Derived Syngas

“…The environmental assessment was carried out using the simplified approach based on the equivalent CO 2 emissions of the plant [ 43 ].…”

Low-Input Crops as Lignocellulosic Feedstock for Second-Generation Biorefineries and the Potential of Chemometrics in Biomass Quality Control

“…For example, in 2019 Da Silva et al published an assessment of different LCF pretreatment processes for bioethanol production. Taking into account five different pretreatment procedures of lignocellulosic biomass, the authors found that diluted acid is the best choice for bioethanol production, with an economic value of $39.2 million per year and an environmental impact of 83.9 kt CO 2 per year [62]. Patel et al tried to quantify the production cost of biodiesel from agricultural waste, a comparative assessment recently reported [63].…”

Biomass Availability Based Novel Approach for Lignocellulosic Biorefineries and Biomethane Plants

“…Biomass that does not compete directly with the food industry should be used, like agricultural and forest residues [2]. Several works aim to assess a techno-economic analysis of biorefineries producing liquid fuels (i.e., ethanol) [3], solid fuels (i.e., pellet) [5], chemicals (i.e., levulinic acid, succinic acid) [6]. Other works aim to assess supply chain optimization [7] for the biomass-biorefineries.…”