Development of Cold-Bonded Briquettes Using By-Product-Based Ettringite Binder from Ladle Slag
Ahmed Abdelrahim, Hoang Nguyen, Mamdouh Omran, Päivö Kinnunen, Mikko Iljana, Mirja Illikainen, Timo Fabritius
Abstract
Abstract The recycling of steel plant side streams through cold-bonded briquettes has become quite common. However, Portland cement is mainly used as a binder in the briquettes, contributing significantly to the energy consumption, costs, and carbon footprint associated with the production of cold-bonded briquettes. This paper reports on a more sustainable method for side stream recycling that involves replacing cement with an ettringite-based binder. Ettringite binders develop early high strength and mainly consist of ladle slag, another side stream of the industry. Here, the ettringite-based binder is assessed in terms of its mechanical and thermal properties against a reference briquette made using the conventional technique. Three different briquette types are produced using several side stream materials and varying ettringite-based binder content. Briquettes produced using 15% and higher ettringite-based binder content exhibited excellent mechanical properties within a shorter curing period compared to conventional used binder. Moreover, the ettringite-based binder briquettes exhibited a better swelling behavior to conventional cement briquettes under conditions simulating a blast furnace. Graphical Abstract