Feasibility Study on Replacing Steam by Carbon Dioxide for Concrete Masonry Units Curing
SourceThe feasibility of replacing steam by carbon dioxide in concrete masonry units (CMU) curing was studied for carbon dioxide utilization and performance improvement. A laboratory study had shown that CMU could uptake 18 %–24 % CO2 by mass based on cement content through a carbonation period of 2–4 h. In comparison to steam process, carbonated CMUs could have equivalent strength and much improved durability performance. If all CMUs produced in the United States can be treated by carbon dioxide curing, approximately 1.5 × 106 tonnes of CO2 will be utilized each year. If this CO2 is captured from cement kilns, the reduction of carbon emission for US cement industry will reach 3 % due to the contribution by CMU industry alone. The carbon dioxide curing of CMU will facilitate carbon capture and storage with benefits to both environment and business.