Comparative Evaluation of Co 2 Uptake in Recycled Crusher-Run Derived From Waste Concrete： Effects of Natural and High-Pressure Carbonation

Key Points

• This research aims to compare CO2 uptake in recycled materials derived from waste concrete under different carbonation conditions.
• Conducted exposure tests at 20°C and 35°C for 28 days to evaluate CO2 fixation by particle size.
• Performed autoclave carbonation tests under high CO2 pressure (60°C, 2.5MPa).
• Compared the efficiency of natural carbonation versus high-pressure carbonation.
• Finer particle sizes led to increased CO2 fixation.
• Natural carbonation showed significant CO2 uptake, especially in the first 7 days.
• Maximum CO2 fixation achieved was estimated at 45kg-CO2/t after 28 days.
• High-pressure carbonation achieved CO2 uptake equivalent to 28 days of natural carbonation within 3 hours, but reduced net CO2 reduction due to energy consumption.