AWWA WQTC69460

Adenovirus has been shown to have a high resistance to low pressure ultraviolet (UV). For 4-log virus creditin the LT2ESWTR, a low pressure UV dose of 186 mJ/cm² is required. UV reactors must bebioassay validated to achieve credit per the LT2ESWTR, but currently available challengemicroorganisms are not able to demonstrate these high dose values. For example, using MS2bacteriophage, which ranges in resistance from 18-25 mJ/cm²/log, 7.4-10.3 log reductions ofMS2 would be required. This is operationally very difficult to do at any reasonable scale. This studyset out to find a highly UV resistant microorganism that could be cultured to high titers, fordoing practical demonstrations of high UV resistances. The study used spores of the fungusAspergillus niger, and characterized them with a low pressure UV collimated beam. To showthe feasibility of their practical usage, A. niger spores were used to do full scale challenges of aresidential scale low pressure UV reactor (up to 68 L/min flow) and a municipal drinking waterscale medium pressure UV reactor (up to 2100 L/min flow). The study successfully demonstratedreduction equivalent doses > 400 mJ/cm² using the A. niger spores, making these spores a viablechoice for high dose UV reactor challenges such as those required to achieve multi-log viruscredit for the LT2ESWTR. Includes figures.

Product Details

Edition:

Vol. - No.

Published:

11/01/2008

Number of Pages:

4

File Size:

1 file , 780 KB