Sustainability assessment of CO2 capture across different scales of hard-to-abate emission sources

Carbon capture, utilization and storage (CCUS) can support the decarbonization of hard-to-abate industries, where carbon-containing raw materials are integral to core processes. Given the vast portfolio of carbon capture technologies and the specificity of each industry, comprehensive decision-making frameworks are essential for identifying the most suitable option in each case. A quantitative approach to the early-stage sustainability assessment of industrial carbon capture (CC) technologies is proposed, incorporating inherent safety quantification as a proxy for social sustainability. Two case studies were defined to test the method, considering industrial plants with varying emission scales and flue gas compositions in the ceramic and cement sectors. Considering 590,000 t/y of avoided CO2 emissions achieved by applying CC to multiple ceramic plants, CO2 avoidance costs resulted in the range of 369–509 €/tCO2, with an increase up to 300 % when compared to the costs of CC application to a single cement plant, which has a 45 times higher emission rate. Regarding the safety domain, results suggest that the increased likelihood of potential accidents when carbon capture is applied to multiple distributed sources rather than a single large emitter is a point of attention. Notably, safety-related impacts increase as much as 87 %, while environmental impacts are less affected by the scale. In comparing technologies, safety-related impacts appear uncorrelated with other sustainability indicators, underscoring the importance of their inclusion for a comprehensive sustainability assessment. When inherent safety is considered, amine scrubbing emerged as the least sustainable option, with a hazard index at least 25 times higher than alternative CC technologies not involving the use of solvents.