Process for improving fly ash quality, improved fly ash, and cementitious compositions containing improved fly ash
US11472737B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Feb 25, 2021 |
| Grant date | Oct 18, 2022 |
| Priority date | — |
| Expiry date | May 10, 2041 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02W30/91
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A non-conforming (or barely conforming) fly ash is converted into conforming (or better conforming) fly ash by: (1) obtaining an initial fly ash with at least one non-conforming (or barely conforming) characteristic selected from excess carbon content, low strength activity index, or low SAF as defined by ASTM C-618 and having a D10, D50 and D90; (2) classifying the initial fly ash using one or more air classifiers to produce at least two separate fly ash streams, including fine fly ash and coarse fly ash; (3) collecting the fine fly ash and the coarse fly ash, the fine fly ash having a D90 less than the D90 of the initial fly ash; (4) combining the fine fly ash with an aluminosilicate source to form a modified fly ash having a conforming carbon content, a conforming reactivity index, and a conforming SAF as defined by ASTM C-618.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.