CO2 Mineralization and Utilization using Steel Slag for Establishing a Waste-to-Resource Supply Chain

Abstract

Both steelmaking via an electric arc furnace and manufacturing of portland cement are energy-intensive and resource-exploiting processes, with great amounts of carbon dioxide (CO2) emission and alkaline solid waste generation. In fact, most CO2 capture and storage technologies are currently too expensive to be widely applied in industries. Moreover, proper stabilization prior to utilization of electric arc furnace slag are still challenging due to its high alkalinity, heavy metal leaching potentials and volume instability. Here we deploy an integrated approach to mineralizing flue gas CO2 using electric arc furnace slag while utilizing the reacted product as supplementary cementitious materials to establish a waste-to-resource supply chain toward a circular economy. We found that the flue gas CO2 was rapidly mineralized into calcite precipitates using electric arc furnace slag. The carbonated slag can be successfully utilized as green construction materials in blended cement mortar. By this modulus, the global CO2 reduction potential using iron and steel slags was estimated to be ~138 million tons per year.

A comprehensive review on mechanical and durability properties of cement-based materials containing waste recycled glass

“…This CO2 is a major contributor to the greenhouse gases which cause global warming (Huntzinger and Eatmon, 2009;Pade and Guimaraes, 2007). Therefore, there is a need for alternative binder materials such as fly ash (Wang et al, 2004), silica fume (Chaipanich and Nochaiya, 2009), slag (Pan et al, 2017), etc. that can partially or completely replace Portland cement in concrete.…”

Integrated Mineral Carbonation of Ultramafic Mine Deposits—A Review

“…Since burning of fossil fuels causes a carbon flux from the lithosphere to the atmosphere, strategies and solutions that reverse this process by creating a carbon flux from the atmosphere back to the lithosphere can permanently solve the current anthropogenic CO 2 problem and mitigate global warming. CO 2 sequestration by mineral carbonation is such a process that could permanently store CO 2 and establish a "circular economy" [9]. The mining industry could potentially apply mineral carbonation using ultramafic mine wastes and offset their greenhouse gas emissions.…”

Usage of Steel Slag as a Construction Material and in Environmental Applications

“…Their results indicate that the carbonation reaction of steel slag is controlled not only by the reaction kinetics but also the diffusion of the reactive CO2. A direct CO2 reduction annually from flue gas was estimated at 0.137 Gt CO2 when iron and steel slags were applied for CO2 mineralization [55].…”