CSAB clinkers were produced using metallurgical residues.
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Fe and fayalitic slag are used to make CSAB with ye'elimite, belite, and ferrite.
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The fluorine content in AOD slag enabled the formation of fluorellestadite.
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Compressive strength of the produced CSAB mortars is comparable to commercial PC.
Abstract
Blast furnace slag from the steel industry is commercially utilized as a cement replacement material without major processing requirements; however, there are many unutilized steel production slags which differ considerably from the blast furnace slag in chemical and physical properties. In this study, calcium sulfoaluminate belite (CSAB) cement clinkers were produced using generally unutilized metallurgical industry residues: AOD (Argon Oxygen Decarburisation) slag from stainless steel production, Fe slag from zinc production, and fayalitic slag from nickel production. CSAB clinker with a target composition of ye'elimite-belite-ferrite was produced by firing raw materials at 1300 °C. The phase composition of the produced clinkers was identified using quantitative XRD analyses, and the chemical composition of the clinker phases produced was established using FESEM-EDS and mechanical properties were tested through compressive strength test. It is demonstrated that these metallurgical residues can be used successfully as alternative raw materials for the production of CSAB cement that can be used for special applications. In addition, it is shown that the available quantities of these side-streams are enough for significant replacement of virgin raw materials used in cement production.
Graphical abstract
Abbreviations
AAS
aluminium anodizing sludge
AOD
Argon Oxygen Decarburisation
AOD_C
CSAB clinker produced from reagent grade chemicals and AOD slag
CO2e
equivalent CO2 emissions
BCSA
belite calcium sulfoaluminate
BOF
basic oxygen furnace
BSE
back-scattered electron detector
CSA
calcium sulfoaluminate
CSAB
calcium sulfoaluminate belite
Fay_C
CSAB clinker produced from reagent grade chemicals and fayalitic slag
Fe_C
CSAB clinker produced from reagent grade chemicals and pyrometallurgically treated jarosite