Study of carbon dioxide capture potential due to direct carbonation of metallurgical slags

Abstract

Due to the increased use of fuels in industry, a huge amount of carbon dioxide is released into the at-mosphere, which is considered one of the main causes of global warming. Steel and ferrous metallurgy slags are a type of solid waste that contains a large number of alkaline mineral phases and can effec-tively capture carbon dioxide. This work is devoted to the study and analysis of the possibility of var-ious types of metallurgical slags, their ability to bind carbon dioxide in the process of direct carbona-tion is analyzed. To solve the tasks set, the chemical and phase compositions of the slags were deter-mined, and the content of minerals in the slags capable of participating in the carbonization process was estimated. The results showed that compounds and phases potentially active for carbonation in the technology of carbon dioxide binding are present in the slags formed in a ladle-furnace unit and blast furnace slags. However, under the selected conditions (direct carbonation, medium temperature 20 °C, ratio of liquid and solid phases L/S = 10, carbonation time 30 minutes), the slags formed in a ladle-furnace are best suited for the binding of carbon dioxide into stable solid carbonate compounds. At the same time, the main reactive substances capable of carbonation in this type of slag are peri-clase (MgO) and calcium silicate (C2S), the mass fraction of which is 4.6% and 60.1%, respectively.