A 1 um diameter fluorescent microsphere was selected and characterized for use as a
photobleachable probe of ultraviolet (UV) fluence in a disinfection reactor. Loss of fluorescence
(photobleaching) was calibrated as a function of fluence, and this relationship was found not to
be significantly affected by water quality parameters, if oxidants such as hypochlorite were
excluded. Photobleaching was also determined to be caused by the UV portion of the medium
pressure lamp spectrum, especially wavelengths below 300 nm. Microspheres were injected into
the inlet of a pilot scale UV reactor and recovered in outlet samples for subsequent analysis by
flow cytometry. Data from flow cytometry, together with the calibration data, were used to
construct a histogram of UV fluence for the reactor, showing behavior consistent with previous
predictions in other reactors. Improvement of the sensitivity of the technique is required to
permit direct measurement of the minimum UV fluence.
Includes 14 references, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 290 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 11 |
| Published : | 11/02/2003 |
