Use of steel slag as carbonation material: A review of carbonation methods and evaluation, environmental factors and carbon conversion process

Steel slag, as a major solid waste in the steel industry, and its rational disposal is of significant meaning to the carbon emissions of the steel industry. Using steel slag as the carbon sequestration material to absorb the carbon dioxide from flue gases in the production process can realize the waste reuse and at the same time slow down the process of global warming. Although there have been many reports on the carbonation of steel slag, there is a lack of systematic reviews on the process and effect of steel slag carbonation. In this paper, the carbonation methods of steel slag and the evaluation methods of carbonation sequestration are reviewed in detail, and the effect of environmental factors on carbonation of steel slag are described. The mineral transformation and mechanism during carbonation are investigated, and the environmental and social benefits of steel slag carbonation are briefly explained. The study shows that aqueous carbonation is a widely used technical route, and temperature is the most significant factor affecting the carbonation effect of steel slag. Steel slag carbonation has a very broad application prospect and has significant technological advantages in the global warming background.