A 10,000 ton-CO2/y mineralization curing (CMC) process was demonstrated in Jiaozuo city, China by retrofitting a traditional autoclaved curing plant. An industrial concrete formula with synergistic effects of aggregate gradation, early hydration, and alkali excitation was developed using local solid wastes resources. Approximately 90% of the raw materials, including fly ash, furnace blaster slag, steel slag, and carbide slag, came from coal-based industries. An extraordinary phenomenon of high-temperature accumulation from room temperature to 140°C was first observed in an industrial scale because of the rapid and strong exothermic carbonation reaction. A step pressure-equalizing procedure was developed to achieve a rapid carbonation rate, a high CO2 conversion ratio of >98%, and efficient carbonation exotherm recycling. The global warming potential life cycle analysis revealed that compared with autoclaved curing, CMC showed significantly decreased the emission of 182 kg CO2-Eq/m3-product, with direct CO2 sequestration accounting for ∼65% of the reduction.
Keywords: civil engineering; energy sustainability; green engineering; mechanical engineering.
© 2022 The Author(s).