二氧化碳养护混凝土活性组分固碳率评价方法

As a new CO₂ utilization technology, carbonation curing can not only recycle industrial solid wastes, but also sequestrate greenhouse gases permanently, which has attracted more and more attention in recent years. However, due to the complex compositions of raw materials and diverse curing processes, the assessment methods for CO₂ uptake ratio are different. Thus, it is urgent to form a universal assessment method suitable for different concrete products and curing processes. After comparing many assessment methods of CO₂ uptake ratio, a new weight gain and oven-dry method with good applicability and operability and a new basis based on the revised mass of reactive compositions have been proposed. Based on the Steinour formular, the inert compositions in calcium and magnesium components are further deducted, which can help for reasonable assessment of the effective reaction degree of reactive compositions. For cement paste samples, results showed that oven-dry method could compensate the error caused by water evaporation more reasonably, and it was suitable for industrial-scale CO₂ uptake ratio evaluation. For solid waste concrete samples, results showed that the basis of modified reactive compositions mass reflected the carbonation degree of the reactive compositions, and the influences of moisture content and inert components were excluded. Finally, the assessment method proposed in this paper was used to evaluate the CO₂ uptake ratio of carbonation-cured concrete in the industrial demonstration of Jiaozuo, Henan, which provided a more reasonable method of the carbonation curing technology.