Recovery and beneficiation of pozzolan deposits for enhanced performance in concrete

Abstract

Disclosed is a method for enhancing the performance of concrete includes, providing a cementitious mixture comprising cement and processed high calcium fly ash; wherein a processing of the processed high calcium fly ash neutralizes a cementitious reactivity of a high calcium fly ash, wherein a pozzolanic reactivity of the processed high calcium fly ash is maintained during the processing of the high calcium fly ash. The processing of the high calcium fly ash includes hydrating and carbonating the high calcium fly ash. The processing further includes excavating the high calcium fly ash from a landfill or surface impoundment after the hydrating and carbonating. Also disclosed is a portland-pozzolan blended cement mixture with clinker, gypsum, and a pozzolanic material, such as processed high calcium fly ash. After processing, the cementitious reactivity of a high calcium fly ash is neutralized, while pozzolanic reactivity of the high calcium fly ash is maintained.

Dependencies are inferred from the claim text.