Effect of boron oxide on stability of high-ferrite Portland cement clinker in low-temperature calcination

This study delves into the challenges posed by the low-temperature calcination of high-ferrite Portland cement (HFPC) clinker and explores the potential of boron oxide (B₂O₃) as a stabilizing agent. Clinker production is a major contributor to global carbon dioxide emissions, and finding sustainable solutions is paramount. At 1350 °C, the HFPC clinker exhibits severe pulverization due to the metastable nature of the C₂S phase formed at low temperature. To address these challenges, various stabilizing agents, including K₂O + Na₂O, barium carbonate (BaCO₃), calcium fluoride (CaF₂), and B₂O₃, were investigated. K₂O + Na₂O, BaCO₃, and B₂O₃ exhibited promising stabilization effects, although K₂O + Na₂O negatively impacted the stability, and BaCO₃ resulted in significant retardation. Consequently, B₂O₃ was chosen as the preferred stabilizing agent for the low-temperature calcination of HFPC clinker. However, it was observed that the B₂O₃ content should not exceed 1% to prevent destabilization of the C₃S phase, which affects early-stage strength development. This research contributes to the understanding of HFPC clinker stability under low-temperature conditions and provides a potential avenue for reducing energy consumption and carbon emissions in HFPC clinker production.