Pelletizing ash
US5137753A · kind A · utility
Inventors
Key dates
| Filing date | Oct 25, 1990 |
| Grant date | Aug 11, 1992 |
| Priority date | — |
| Expiry date | Oct 25, 2010 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2991
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Ash from a fluidized bed combustor in which limestone particles are suspended in the presence of carbonaceous fuel being burned is pelletized. Lime-containing bed ash ("FBCR") is produced in the combustor, and fly ash ("FBC fly ash") is generated as a by-product of the combustion process. FBCR and FBC fly ash generated during the combustion process are obtained. Water is added to the FBCR so as to convert a substantial portion of the lime to hydrated lime. Water is added to the FBC fly ash and pellets are formed from the FBC fly ash. The FBC fly ash pellets are coated with the hydrated FBCR. The coated FBC fly ash pellets are cured in a curing silo for a minimum of 6-10 hours, preferably by nesting them in a bed of hydrated FBCR. The cured pellets then are separated from the bed of hydrated FBCR. New pellets are formed by mixing the separated, hydrated FBCR with FBC fly ash and water. The pellets formed with the separated, hydrated FBCR contain about 0-80% by weight of FBCR and about 100-20% by weight of FBC fly ash. Agglomeration of the pellets in the curing silo is prevented by coating the pellets with hydrated FBCR. Agglomeration also can be prevented by spraying newly formed pe…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.