Ciments à pouzzolanes et procédé pour leur préparation.

摘要

A barium flue ash cement is made by the fine grinding and mixing of a barium cement with flue ash in the ratio 15-70% of flue ash to 85-30% of barium cement having the compositions SiO2: 6-15%; Al2O3: 3-9%; FeO2: 2-9%; BaO: 60-85%; Cao: 0-4%; MgO: 0-2% and alkali 0-2%. The barium cement may be wholly or partially replaced by natural barytes or natural witherite which has been burnt until converted into BaO. The barium cement, or the barytes or witherite, may be partially replaced by Portland cement. In examples (1) 65 parts of barium-cement clinker is finely ground and homogeneously mixed with 35 parts of flue ash having composition:-SiO2: 50-56%; Al2O3: 30-24%; FeO3: 7-62%; CaO: 2-80%; MgO: 1-52%; SO3: O-20% and alkali 5-35%. (2) 75 parts of barium-cement clinker are mixed with 25 parts of flue ash of composition CaO: 40-50%; SiO2: 39-32%; Al2O3: 5-82%; Fe2O3: 1-24%; MgO: 0-25% and SO3: 3-24%.