Spheroidal slag and fly ash particles and apparatus and process for producing same
US6746636B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | May 30, 2001 |
| Grant date | Jun 8, 2004 |
| Priority date | — |
| Expiry date | Feb 26, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2993
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
The present invention provides spheroidal particles of coal slag, and methods of making the spheroidal particles. One method of the invention includes delivering a feedstock of irregularly shaped particles of coal fly ash or coal slag to a drop tube, dropping the irregularly shaped particles into the drop tube in a manner such that the irregularly shaped particles flow in a substantially vertical downward path as individualized particles, and heating the irregularly shaped particles to cause at least the outer surface of the irregularly shaped particles to melt and form spheroidal particles due to surface tension at the outer surface. The spheroidal particles typically have a diameter in the range of about 0.001 to 5 mm, and comprise SiO2, Al2O3, Fe2O3, FeO, Na2O, and K2O.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.