Modelling and simulation of CO2 capture through aqueous indirect mineralization using CaO-containing by-products

Abstract

Mineralization of CaO-rich industrial wastes by CO2 is a way to simultaneously obtain CO2 sequestration and tackle waste pollution problems. In such a process, CO2 reacts with the CaO in the waste and the produced CaCO3 can be utilized.In this study, four different mineralization processes applying different chemicals, all with a relatively high performance documented from laboratory experiments, are scaled up to industrial size and outlined with the required process equipment. Based on published lab results, mass and energy balances of the up-scaled processes are performed, and performance parameters of the processes are calculated using an in-house made process simulation tool. Furthermore, an economic analysis is done for all processes, and the results are compared. Factors impacting the techno-economic feasibility of each process are evaluated through a sensitivity study.The results indicate that the potential of capturing CO2 and producing CaCO3 can be as high as 530 kg and 1200 kg per ton of the waste while the yearly energy consumption can be as low as 0.7 kWh per kilogram of captured CO2. The aqueous indirect mineralization of CO2 can be profitable and the emitted CO2 by the process can be so low as 6% of the captured amount.