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The carbon capture, utilisation and storage (CCUS) process chain is subject to increasing interest, and its overwhelming implementation on the industrial scale appears to be one of the main ways to reduce CO 2 emissions. In this context, the optimisation of a CO 2 purification process for oxy-combustion cement plant flue gases is proposed. This optimisation is based on a multidimensional study on the energy, exergy, economy, and environmental impacts of the process. The results of the optimisations carried out show that it is more favourable to increase the CO 2 recovery above 90%, from an energy, exergy and economic point of view. The analysis of the evolution of the capture cost as a function of the CO 2 recovery shows that for a given carbon tax, there is a minimum for the total cost which includes the sum of the carbon tax contributions for the uncaptured CO 2 and the capture cost. As the unit uses only electrical energy, the cost and the electricity generation will directly impact the capture cost as well as the overall balance in terms of CO 2 avoided. As the electricity price increases from 50 to 250 €/MWh, the CO 2 capture cost increases by almost 250%. An analysis of the parameter uncertainties allows to observe their impacts on the results, and to define a standard deviation from the optimised points and show the robustness of these. Considering the technical parametric uncertainties, the standard deviation on the electrical consumption (3.65 kWh/t CO2), CO 2 recovery (0.09%) and exergy efficiency (0.92%) is limited. • Study of hybrid CO 2 capture system combining cryogenic and membrane technologies. • 4E analyses considering recovery, energy consumption, exergy yield and capture cost. • Maximum exergy efficiency for the cases where the CO 2 recovery is above 90%. • High sensitivity of the electricity price on the CO 2 capture cost. • Uncertainty quantification of modelling assumptions and impact on 4E analyses. [ABSTRACT FROM AUTHOR]

• Study of hybrid CO 2 capture system combining VPSA and CPU technologies. • Optimization of integrated capture CO 2 process and purification unit. • High CO 2 recovery (90–99 %) and high CO 2 purity (>99.99 %) • Complete analyses considering recovery, energy consumption, and capture cost. • Impact of the electricity source on the total CO 2 recovery. The imperative challenge posed by climate change requires urgent actions to counteract the harmful effects of greenhouse gas emissions, particularly CO 2 , which contributes to approximately 80 % of emissions responsible for global warming. A hybrid system combining Vacuum Pressure Swing Adsorption (VPSA) unit with a Cryogenic Carbon Purification Unit (CPU) is evaluated to enhance recovery and purity of CO 2 captured from flue gas containing CO 2 concentration ranging from 5 % to 20 %. VPSA preconcentrates the CO 2 and CPU completes the separation and purifies the CO 2. The study uses surrogate models for multi-objective optimization, considering energy consumption, cost, and CO 2 recovery, providing a time-efficient approach for investigating computationally demanding processes. Results from the study indicate that the hybrid system achieves over 90 % recovery for flue gas concentration range considered, while ensuring the production of high-purity CO 2 (>99.99 %) suitable for transportation. A trade-off analysis reveals the balance between recovery, electricity consumption, and economic viability. A sensitivity analysis identifies parameters influencing recovery and energy consumption, providing guidance for future optimization efforts. The techno-economic analysis highlights the impact of electricity prices and carbon taxes on total costs, identifying an optimum towards higher recovery values under rising carbon taxes. Furthermore, the research underscores concentration-dependent economic feasibility, emphasizing the attractiveness of concentrations above 10 % compared with other technologies, which require higher concentrations. For an electricity price of 75 €.MWh−1, the total cost of the CO 2 capture hydride system considering CO 2 emissions with carbon tax of 100 €.t CO2 −1 for concentrations ranging from 10 % to 20 % is from 123 to 80 €.t CO2 −1, respectively. The analysis of the electricity source shows the importance of a low-carbon emission energy mix for optimal carbon emission reduction. [ABSTRACT FROM AUTHOR]