Oxyfuel Combustion Makes Carbon Capture More Efficient

Saeed Talei; Daniel Fozer; Petar Sabev Varbanov; Agnes Szanyi; Peter Mizsey

doi:10.1021/acsomega.3c05034

Oxyfuel Combustion Makes Carbon Capture More Efficient

ACS Omega. 2024 Jan 10;9(3):3250-3261. doi: 10.1021/acsomega.3c05034. eCollection 2024 Jan 23.

Authors

Saeed Talei¹, Daniel Fozer², Petar Sabev Varbanov³, Agnes Szanyi^{1

4}, Peter Mizsey⁵

Affiliations

¹ Institute of Chemistry, University of Miskolc, H-3515 Miskolc, Hungary.
² Department of Environmental and Resource Engineering, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark.
³ Sustainable Process Integration Laboratory - SPIL, NETME Centre, FME, Brno University of Technology - VUT Brno, Technická 2896/2, 616 69 Brno, Czech Republic.
⁴ Department of Chemical and Environmental Process Engineering, Budapest University of Technology and Economics, H-1521 Budapest, Hungary.
⁵ Higher Education and Industrial Cooperation Centre, University of Miskolc, H-3515 Miskolc, Hungary.

Abstract

Fossil energy carriers cannot be totally replaced, especially if nuclear power stations are stopped and renewable energy is not available. To fulfill emission regulations, however, points such as emission sources should be addressed. Besides desulfurization, carbon capture and utilization have become increasingly important engineering activities. Oxyfuel technologies offer new options to reduce greenhouse gas emissions; however, the use of clean oxygen instead of air can be dangerous in the case of certain existing technologies. To replace the inert effect of nitrogen, carbon dioxide is mixed with oxygen gas in the case of such air combustion processes. In this work, the features of carbon capture in five different flue gases of air combustion and such oxyfuel combustion where additional carbon dioxide is mixed with clean oxygen are studied and compared. The five different flue gases originate from the gas-fired power plant, coal-fired power plant, coal-fired combined heat and power plant, the aluminum production industry, and the cement manufacturing industry. Monoethanolamine, which is an industrially preferred solvent for carbon dioxide capture from gas streams at low pressures, is selected as an absorbent, and the same amount of carbon dioxide is captured; that is, always that amount of carbon dioxide is captured, which is the result of the fossil combustion process. ASPEN Plus is used for mathematical modeling. The results show that the oxyfuel combustion cases need significantly less energy, especially at high carbon dioxide removal rates, e.g., higher than 90%, than that of the air combustion cases. The savings can even be as high as 84%. Moreover, 100% carbon capture was also be completed. This finding can be due to the fact that in the oxyfuel combustion cases, the carbon dioxide concentration is much higher than that of the air combustion cases because of the inert carbon dioxide and that higher carbon dioxide concentration results in a higher driving force for the mass transfer. The oxyfuel combustion processes also show another advantage over the air combustion processes since no nitrogen oxides are produced in the combustion process.