Abstract：This study investigates the impact of replacing limestone with
calcareous slag derived from acid production using phosphogypsum on the
formation process of Portland cement clinker. By varying calcareous slag
incorporation ratios and calcination temperatures, the mineral
composition and burnability of clinker were analyzed through
measurements of free lime (f-CaO) content, XRD, and petrographic
analysis. The results demonstrate that calcareous slag from
phosphogypsum can replace limestone at incorporation ratios ≤28% for
Portland clinker production. Fluorine and sulfur present in the
calcareous slag catalyze solid-state reactions of clinker minerals.
Elevated calcination temperatures significantly reduce f-CaO content,
and Portland cement clinker shows good compatibility with calcareous
slag incorporation.
2026, Vol. 0 
