CARBONATED FLY ASH AS A CEMENT REPLACEMENT

摘要

A process for producing a blended binder material containing high calcium fly ash, in particular ASTM Class C fly ash, is provided. The process comprises: (i) carbonating the fly ash with carbon dioxide; and (ii) combining the carbonated fly ash with a cement binder such as Portland cement. The carbonation process improves the performance of the high calcium fly ash and thus allows for higher amounts of the fly ash to be used with the cement binder in cement mix compositions such as concrete. The results presented herein demonstrate the benefits of the carbonation process on the rate of cement hydration, and on the compressive strength and the dimensional stability of the resulting cement products.