Blue Ammonia and the Supply Chain Pioneering Sustainability Assessment for a Greener Future

With the global shift to sustainability, the energy sector faces pressure to adopt low-carbon solutions. Blue ammonia (BA), derived from natural gas (NG) with carbon capture, presents significant opportunities but requires a holistic sustainability assessment. This study conducts a novel life cycle sustainability assessment (LCSA) of BA, evaluating environmental, economic, and social impact performance from feedstock processing to maritime transport for a 1.2 MMTPA production capacity. Process simulations in Aspen HYSYS V12 and the ammonia maritime transport operations’ sustainability assessment model provide critical insights. The ammonia converter unit contributes the highest emissions (17.9 million tons CO₂-eq), energy use (963.2 TJ), and operational costs (USD 189.2 million). CO₂ removal has the most considerable land use (141.7 km²), and purification records the highest water withdrawal (14.8 million m³). Carbon capture eliminates 6.5 million tons of CO₂ annually. Economically, ammonia shipping dominates gross surplus (USD 653.9 million, 72%) and tax revenue (USD 65.3 million) despite employing just 43 workers. Socially, the ammonia converter unit has the highest human health impact (16,621 DALY, 54%). Sensitivity analysis reveals transport distance (46.5% CO₂ emissions) and LNG fuel prices (63.8% costs) as key uncertainties. Findings underscore the need for optimized logistics and alternative fuels to enhance BA sustainability.