Sustainable assessment and synergism of ceramic powder and steel slag in iron ore tailings-based concrete

Environ Sci Pollut Res Int. 2024 Mar;31(12):18856-18870. doi: 10.1007/s11356-024-32396-w. Epub 2024 Feb 14.

Abstract

Solid waste management is a critical issue worldwide. Effectively utilizing these solid waste resources presents a viable solution. This study focuses on Iron ore tailings (IOTs), a solid waste generated during iron ore processing, which can be used as supplementary cementitious materials (SCMs) but have low reactivity, hindering their large-scale application in concrete production. To address this, ternary SCMs were prepared using ceramic powder (CP) and steel slag (SS) to enhance the performance of concrete incorporating IOTs. The study found that the synergistic effect of CP and SS significantly improved the compressive strength of concrete, with a notable increase of up to 21% compared to concrete with IOTs alone. Mercury intrusion porosimetry (MIP) and backscattering electron (BSE) analyses revealed that the ternary SCMs significantly optimized the characteristics of the interfacial transition zone (ITZ), which in turn enhanced the compressive properties of the concrete. This contributed to maintaining the structural integrity of the concrete, even amidst variations in the pore structure. Importantly, the incorporation of ternary SCMs led to a 23% reduction in carbon emissions, from 400.01 kg CO2/m3 to 307.48 kg CO2/m3, and elevated eco-strength efficiency from 0.1 to 0.14. The study highlights the role of multi-material synergy in developing composite SCMs systems, fostering the sustainable advancement of green building materials.

Keywords: Ceramic powder; Interfacial transition zone; Iron ore tailings; Pore structure; Steel slag; Synergistic effect.

MeSH terms

  • Carbon Dioxide*
  • Ceramics
  • Iron
  • Powders
  • Solid Waste
  • Steel*

Substances

  • Steel
  • Powders
  • Carbon Dioxide
  • Solid Waste
  • Iron