Simulation-based techno-economic and environmental evaluation of synthetic natural gas production integrated with sugarcane processing

Abstract

Dependence on fossil fuels is accelerating climate change and has spurred interest in carbon capture and utilization, which converts CO₂ into products such as synthetic natural gas (SNG) that fit seamlessly into existing infrastructure. Despite efficient routes such as biomass gasification and Power-to-Gas, high costs have slowed adoption. In the Argentine sugar industry, biogenic CO₂ from sugarcane processing presents an opportunity to produce low-carbon SNG. This study proposes to evaluate the feasibility of SNG production in sugarcane biorefineries through a combined techno-economic and environmental analysis. By capturing CO₂ from biomass combustion and by combining it with hydrogen, sugarcane-processing facilities could serve as carbon sinks and reduce reliance on fossil fuels, contributing to broader decarbonization goals. Two scenarios are considered, green SNG and gray SNG, which differ in the source of electricity, renewable and current grid electricity, respectively. The green SNG system significantly reduces greenhouse gas emissions and fossil resource use by using renewable H₂ and biogenic CO₂, while the gray SNG system has a higher environmental impact due to its reliance on the current Argentine fossil-based electricity. The proposed process achieves an overall feedstock conversion of approximately 97%, which supports its technical feasibility. In addition, preliminary cost considerations are presented, outlining the economic challenges for large-scale implementation. The study also notes that the sustainability of SNG production from biogenic CO₂ depends on the carbon intensity of the electricity grid, underlining the importance of transitioning to renewable energy to maximize environmental benefits.