Use of hazardous electric arc furnace dust in the construction industry: A cleaner production approach

Many steel industries are adopting electric arc furnace (EAF) technology due to the growing demand for steel recycling and reducing greenhouse gas emissions. Nevertheless, the major issue with EAF is the co-production of slag and dust (EAFD). Slag is a hard, dense, and rock-like material, while EAFD is fine dust. EAFD contains oxides of several heavy metals mostly present in input scrap steel or additives used for alloy making. Many environ-mental agencies have categorised EAFD as hazardous waste as EAFD disposed off in land leach heavy metals, contaminating the groundwater. Due to its hazardous nature, EAFD disposal imposes a substantial landfill cost on steel industries. Several studies have reported that EAFD can be utilised in the construction sector as a supple-mentary raw material for cement concrete, asphalt, bricks and ceramics, and other applications, instead of being disposed off in landfills that trigger environmental complications. Yet a review of EAFD reuse in sustainable building material production is lacking. This work reports EAFD production during steel manufacturing and its serious impact on environment, analyses the mechanisms involved in after the addition of EAFD as a secondary filler material in various construction components, namely concrete, asphalt, bricks, ceramics, and glaze. Insights into EAFD morphology and chemical composition and the effect of EAFD addition on the performance of the above components are also presented. This paper also provides an in-depth synthesis of the performance of building materials after EAFD incorporation in terms of workability, hydration, hardening process, mechanical performance, and durability. Literature reports that the fine nature of EAFD improves the workability of concrete and the plasticity of clay used in ceramic tiles and bricks. EAFD fills up the voids and improves water absorption, mechanical strength, and durability of the final product. Eventually, the performance of construction materials blended with EAFD is governed by the bond, quantity, and characteristics of EAFD, including morphology, particle size distribution, and composition. Laboratory trials are required to obtain the optimum mix of EAFD and the binder. Adding EAFD to construction materials is an economical and efficient approach to recycle waste and can be used to build infrastructure while reducing the environmental impact. The paper also discusses a few challenges in the current research and development and future perspectives on using EAFD as a supplementary material. The review anticipates providing a valuable guide to recycle EAFD in construction materials. Incor-porating EAFD in building materials production could be a promising approach to a circular economy and cleaner production.

Automated summary

Many steel industries are adopting electric arc furnace (EAF) technology to recycle steel and reduce greenhouse gas emissions. However, the co-production of slag and dust (EAFD) is a major issue. This paper discusses the environmental impact of EAFD production, analyzes its incorporation in various construction components, and provides insights into its morphology and chemical composition. The study shows that EAFD can improve the performance of building materials and suggests its reuse as a supplementary material for sustainable construction.