Removal of elemental mercury by photoionization
US6663690B2 · kind B2 · utility
3Cited by
9References
30Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Sep 23, 2002 |
| Grant date | Dec 16, 2003 |
| Priority date | — |
| Expiry date | Sep 23, 2022 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01D2257/602
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Elemental mercury is removed from emissions of coal-fired utilities by the selective photoionization of mercury atoms using ultraviolet light, followed by electrostatic precipitation of the mercury ions. Mercury is first exposed to light of a wavelength which boosts the mercury to an excited state. Then mercury is ionized using light of a different wavelength. The ionized mercury atoms are exposed to supersaturated water vapor to produce charged droplets which are precipitated, such that the exhaust effluent is substantially devoid of mercury or the mercury level is substantially reduced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.