Cement manufacture
Industrial Chemistry · Chemistry
Study notes
Why is gypsum added to cement clinker? Step 1: Clinker alone sets too fast (flash set — unworkable). Step 2: Gypsum (CaSO₄·2H₂O, ~5%) retards C₃A hydration. Step 3: Controlled setting → workable concrete hours. Step 4: Retarder tunes timing — gypsum paces the set!