Synthesis and scaled-up of standard and active Belite-Alite-Ye'elimite clinker (BAY)

ABSTRACT: Clinkers with the coexistence of belite-alite-ye´elimite (BAY) are considered as eco-friendly cements due to the reduced CO₂ emissions released during their manufacture. All BAY clinkering parameters have been optimized: raw materials, mineralizers/activators, clinkering conditions and scaled-up methodology. Two types of clinkers were prepared and scaled-up to have ~2 kg: i) standard-BAY (28.4 wt% of b-belite, 41.5 wt% of alite and 17.4 wt% of ye'elimite) by adding CaF₂ and ZnO to the raw mixture; and ii) active-BAY (18.1 wt% of α'_H-belite, 42.1 wt% of b-belite, 15.8(2) wt% of alite, and 7.7(2) wt% of ye'elimite) by using optimized amounts of CaF₂, ZnO and B₂O₃. The microscopy[P1]  study has revealed that primary particle size of belite is larger (~10 µm) in the active clinker than in the standard one (~5 µm). Moreover, ferrite and alite have incorporated most of the Zn and F in their structures in both clinkers, while belite (b and α’_H forms) has preferentially incorporated sulphur.