Optimization-based assessment framework for CO₂ utilization to fuels strategies

Carbon capture and utilization for fuel production is one of the attractive and effective solutions addressing climate change and energy security. In which captured CO₂ is considered as raw materials for high-energy-density products (e.g., methanol, dimethyl ether, Fischer-Tropsch fuel, gasoline) via different technologies (catalytic conversion, thermochemical energizing, electrochemical reduction). This study developed an optimization-based framework to analyze and assess CO₂ utilization strategies for fuel products regarding technical, economic, and environmental performance. To achieve this goal, we first generated a superstructure involving a series of technologies (carbon conversion and separation) to produce value-added fuels from captured CO₂ as a feedstock. We then simulated all the involved processes and estimated the technical and economic parameters (mass and energy flow, and sizing and costing data) that were further adopted into the optimization model. The optimization models were developed to identify the optimal CO₂ utilization strategies with different criteria: energy efficiency, production cost, profit, and CO₂ reduction. As a result, we can determine the best CO₂ utilization strategy over various technological pathways to produce different targeted fuels, which makes CO^2- based fuels economically and/or environmentally viable.