Sustainability prioritization of CCUS systems with consideration of criteria interaction: a fuzzy multi-criteria decision-making framework based on 2-additive fuzzy measure and Choquet integral method

Carbon Capture Utilization and Storage (CCUS) has been demonstrated to be an effective technology for reducing CO2 emissions. This study proposes a Choquet integral-based multi-criteria decision-making (MCDM) framework for the sustainability assessment of alternative CCUS routes. In the framework, the 2-additive fuzzy measure approach is used to evaluate the relative importance of each criterion and criteria subset under the premise of considering and identifying the complementary or redundant relationships between them. The information regarding different criteria covering economic, environmental, social, and technical aspects is then integrated by the Choquet integral approach to prioritize the sustainability of various alternatives. In a case study, the sustainability of five CCUS systems is prioritized to verify the feasibility of the proposed framework, showing that the route of converting CO2 to dimethyl carbonate is the most sustainable one mainly due to its excellent performance in the criterion of "relative added value", which is identified as the most important criterion and has the most interactions with other criteria. The process of producing methanol is evaluated as the second most sustainable alternative for its good performance in both the environmental and social aspects. Furthermore, the effectiveness of the framework is validated by comparing the sustainability ranking result with that by using the conventional TOPSIS method.