Process for increasing the strength of cement obtained from calcium sulfate
Abstract
Abstract IN A PROCESS FOR PRODUCING CEMENT CLINKER FROM CALCIUM SULFATE BY REDUCTION OF THE CALCIUM SULFATE WITH COKE AT 900 TO 1200*C TO PRODUCE SO22 AS A BY-PRODUCT AND CAO AND SINTERING THE CAO WITH ADDITION OF AI2O3-, FE2O3- AND SIO2-CONTAINING MATERIALS THE IMPROVEMENT WHICH COMPRISES SUBJECTING TO THE REDUCTION A MIXTURE OF AT LEAST ONE OF ANHYDRIDE AND NATIVE GYPSUM WITH PHOSPHOROUS GYPSUM HAVING A P2O5 CONTENT OF ABOUT 0.5 TO ABOUT 2.5% BY WEIGHT AND AN F CONTENT OF ABOUT 0.5 TO ABOUT 1% BY WEIGHT, THE WEIGHT PROPORTION OF PHOSPHORUS GYPSUM RELATIVE TO THE TOTAL OF PHOSPHOROUS GYPSUM, ANHYDRITE AND NATIVE GYPSUM BEING 20 TO 90%, AND SUBJECTING TO THE SINTERING THE RESULTANT CAO.
Inventors
- 👤 G Herzog
- 👤 W Riesel
- 👤 R Wagner
- 👤 H Schumann
- 👤 W Wolfrom
- 👤 C Lamm
- 👤 U Munch
- 👤 G Kahle
- 👤 W Kolling
Bibliographic Details
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