Method and apparatus for detecting the presence of elemental mercury in a gas sample
US7354553B2 · kind B2 · utility
Inventors
Key dates
| Filing date | May 2, 2005 |
| Grant date | Apr 8, 2008 |
| Priority date | — |
| Expiry date | Oct 14, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/6408
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An improved elemental mercury analyzer utilizes a fluorescence assembly in combination with a fluorescence quenching reduction mechanism to detect the concentration of elemental mercury within an emission gas sample, via fluorescence of the mercury within the gas sample, while minimizing fluorescence quenching of the gas sample. In one arrangement, the analyzer contains the emission gas sample under a vacuum or negative pressure while detecting fluorescence of the elemental mercury within the emission gas sample. By performing fluorescence detection of the emission gas sample at reduced pressure relative to the pressure of the as-sampled emission gas, the analyzer reduces the number of particle collisions within the emission gas sample over a certain period of time. Such collisional deactivation, and/or the addition of oxygen depleted gas such as nitrogen to the gas sample, reduces fluorescence quenching of the emission gas sample, improving accuracy of detection of mercury.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.