Recycling of iron and steel slag for carbon reduction and low-environment load application

Abstract

The high-value utilization of blast furnace slag (BFS) and steel slag (SS) as a valuable resource in the field of carbon reduction represents a green revolution, and also is an indispensable path toward breaking through resource and environmental constraints and achieving high-quality, sustainable development through solid waste utilization in the steel industry. Achieving resource recycling while harnessing the untapped latent energy of resources and exploring their carbon sequestration capabilities has become a crucial avenue for further valorization through waste utilization. BFS and SS discharged from iron-making or steel-making furnaces carry a significant amount of latent heat, especially the calcium oxide component in SS, which gives it a unique advantage in the field of comprehensive BFS and SS utilization and carbonation-based SS utilization. This article discusses the current research status of low-carbon-waste-heat utilization in the production of microcrystalline glass, cementitious materials, functional adsorbents, and other products through front-end modification of molten BFS and SS. This report also provides an overview of carbon capture by utilizing BFS and SS, offering insights into the research directions for subsequent heat recovery, online quality adjustment, high-value utilization, and carbon sequestration using BFS and SS in the steel industry.