Poster (EARTH)

[PE1-018] Fireproofing Material from Alkali-activated EAF Ladle Slag

○Pai-Haung Shih¹, Dong-Shyuan Lu², Ho-Sheng Tsai², Juin-Ting Wu¹, Juu-En Chang² (1. Fooyin University, 2. National Cheng Kung University)

Keywords:Electric Arc Furnace, Ladle Slag, Alkali-activated Process, Fireproofing

Electric Arc Furnace Steel-making process has become one of the primary steel providing processes in Taiwan. Nevertheless, the potential soundness problem due to the free-CaO content has made EAF ladle slag (LS) limited the reuse of EAF LS. This research attempts to fireproofing porous material from LS by alkali-activated process.
Sampled LS was tested for physical properties and Chemical composition analysis. The results showed that LS could be reuse as cementitious or pozzolanic material. Nevertheless, further accelerated mortar bar test and autoclave expansion suggested that f-CaO content in LS transformed into Ca(OH)₂ in hydration late stage, and resulted in volume expansion with failure in meeting the soundness criteria.
Alkali-activation technique could directly transform f-CaO content in LS into Calcium Silicate hydrate. Hence, Alkali-activated LS (AALS) would not have the Ca(OH)₂ expansion and cracked problem. Further application of foaming agent could develop porous materials with density as low as 800 kg/m³. With this porous AALS process, light-weight fire-proofing partition wall utilization reuse of LS could be developed.