Integrated liquid fuel based chemical looping combustion - parametric study for efficient power generation and CO2 capture

This study investigates an integrated Chemical Looping Combustion (CLC) based power generation system capturing CO2 with an electrical efficiency of up to 55%. The integrated model is developed using Aspen Plus (R), considering fuel oil as a liquid fuel. It consists of (i) a gasification island, (ii) a CLC island, (iii) heat recovery units, and (iv) power generation turbines. The gasification island is employed to ensure reforming of heavy hydrocarbon molecules into easily combustible syngas (CO, H-2). In order to improve the electrical efficiency, a fraction of the gasified fuel is directly fed (bypassed CLC) to a combustor located prior to the gas turbine. The model is evaluated by comparing the CLC island performance with that of the available literature results [28]. The developed model displays good accuracy, with maximum error limit of 3.1%. The integrated model prediction shows that the addition of air supply ratio (from 5 to 9) and inert ratio (from 0.3 to 0.7) can increase the overall efficiency of the process (from 40% to 47%). The efficiency reduces to 31% when the system pressure is increased from 8 to 16 bars. An increase of the split ratio of the producer gas into the combustor (up to 0.15) increases the efficiency (up to 55%). However, the corresponding CO2 emission rises up to 0.10 kg CO2/kW.