Effects of a composition change of ordinary Portland cement on waste utilization and CO₂ emissions in Japan

This paper estimates the effects of a composition change of ordinary Portland cement on waste utilization and CO₂ emissions in the Japanese cement industry based on the previous literature. It is estimated that increasing the aluminate phase content in clinker and using 10 mass% of mineral admixtures result in an increase of 74.6 g/kg-cement in waste use and a reduction of 56.3 g/kg-cement in CO₂ emissions on the business-as-usual basis. This indicates a way to achieve both increase in waste use and reduction in CO₂ emissions at the same time. Based on these results, it is estimated that CO₂ emissions would be reduced by 2080 thousand tons in 2016 and 2140 thousand tons in 2030 from the business-as-usual values. Additionally, waste use for raw materials can be increased by 2760 thousand tons and 2850 thousand tons in respective years.