Erie Water Works (EWW) conducted an evaluation of the use of membrane filtration to
replace an existing conventional filtration process. EWW's objective was to provide filtration
that will reliably produce water exceeding the Safe Drinking Water Coalition requirements
and prepare the utility for more stringent drinking water regulations, while providing
increased public protection against acute illness caused by Cryptosporidium. EWW
conducted a pilot study with two different low-pressure submerged membrane system
manufacturers, along with a log removal validation study for each membrane system, using
fluorescing microspheres as the surrogate for the pathogenic organisms. The Long-Term 2
Enhanced Surface Water Treatment Rule (LT2ESWTR) requires that membrane filtration
systems used for Cryptosporidium removal undergo a challenge test to establish the
maximum log removal value (LRV) that a membrane system can achieve. While a number of
third-party challenge tests for both products have been historically conducted, EWW
requested that additional testing be conducted at their facility as a demonstration.
Following evaluation of various challenge test methods, EWW selected fluorescing
microspheres as surrogates for Cryptosporidium for the challenge study. The basic protocol
was modeled on guidance provided in the United States Environmental Protection Agency
(USEPA) Membrane Filtration Guidance Manual. The microsphere testing concluded that
both low-pressure submerged membrane systems achieved LRVs greater than 5.3. These
results confirm that low-pressure membrane filtration will meet the requirements of the
LT2ESWTR. EWW intends to proceed with full-scale design of a low-pressure
submerged membrane filtration system. Includes 6 references, tables, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 3 MB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 40 |
| Published : | 11/01/2009 |
