Recycling of ferronickel slag tailing in cementitious materials

Recycling of ferronickel slag tailing in cementitious materials: Activation and performance

Chi, Lin (University of Shanghai for Science and Technology)
Lu, Shuang (Harbin Institute of Technology)
Li, Z. (TU Delft Materials and Environment)
Huang, Chendong (University of Shanghai for Science and Technology)
Jiang, Hui (Harbin Institute of Technology)
Peng, Bin (University of Shanghai for Science and Technology)

2023

As an industrial by-product containing pozzolanic components, recycled ferronickel slag (FNS) has the potential to be supplementary cementitious materials (SCMs) to reduce the massive carbon footprint of the cement industry, however, the main limitation of ferronickel slag as SCMs is the low hydration rate at an early age. In this study, the pozzolanic activity property results indicate that if the proportion is more than 10 %, FSN can hardly participate in the cement hydration reaction during the early stage, even the mechanical strength of FNS-mortar decreases obviously with the higher proportion of ferronickel slag. Therefore, mechanical grinding and steam curing at an early age are applied to promote the reaction activity of the recycled ferronickel slag tailing in this study. Compared with standard curing, the compressive strength of hardened FNS-cement paste with steam curing at 60 °C or 80 °C increased by 8.2 % or 33.8 %, and the connected porosity decreased by 18.9 % or 17.3 %. And MgO in the ferronickel slag exists as Mg₂SiO₄ in raw materials and enters the C-S-H gel with the formation of M-S-H gel during the secondary hydration stage. This study provides a theoretical basis for solid waste-based concrete and promotes the recycling, conservation, and resources of solid waste in building materials.

Ferronickel slag
Grinding and heat curing
Hydration mechanism
SCMs

http://resolver.tudelft.nl/uuid:073ef758-c26a-4ecb-8cb2-6ba16aee6439

https://doi.org/10.1016/j.scitotenv.2022.160706

2023-07-01

0048-9697

Science of the Total Environment, 861

Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.

Institutional Repository

journal article

© 2023 Lin Chi, Shuang Lu, Z. Li, Chendong Huang, Hui Jiang, Bin Peng