By: PCI Membrane Systems, Inc.
The U.S. Environmental Protection Agency (EPA) verified that
the Fyne Process water treatment system from PCI Membrane Systems, Inc. in Milford,
Ohio, is able to meet stringent EPA disinfection byproduct (DBP) standards. A
study published as part of the EPA's Environmental Technology Verification
(ETV) Program verifies the performance of a Fyne Process membrane filtration
plant tested on high organic-laden surface water in Barrow, Ark. The plant was
able to remove significant levels of organics--precursors to disinfection
byproducts such as trihalomethanes (THM) and haloacetic acids (HAA)--producing
water that easily met the disinfection byproduct standards set by the EPA's
stringent Stage 1 D/DBP Rule.
Barrow's untreated water had an average total organic carbon
(TOC) level of 15 mg/L and with moderate turbidity. Over the 57-day test
period, the average TTHM concentration was reduced from 535 µg/L in
chlorinated raw water to just 31 µg/L in water chlorinated after
nanofiltration in the Fyne Process test plant. Average HAA(5) concentrations
were reduced from 398.4 µg/L to just 6.2 µg/L. The membrane system
also reduced UV254 absorbance, total organic carbon and turbidity--measures of
water color and clarity--by 97.5 percent, 95.4 percent and 98.3 percent,
respectively.
The ETV program was implemented to assist in the development
of innovative, cost-effective environmental technologies including packaged
drinking water treatment systems. This chemical-free nanofiltration membrane
process was specifically designed to meet the needs of small communities. The
technology already is used extensively in Great Britain and, more recently, in
North America.
DBP concentration is an issue in cities such as Barrow,
which depend on surface water for drinking. In Alaska, the northeast United
States and along the rocky Canadian Shield, it is difficult to drill wells.
Smaller communities in these areas often rely on surface water that tends to be
heavy with dissolved organic materials. Heavy chlorination is required and that
can lead to high TTHM and HAA(5) concentrations in the treated water. Studies
have shown that TTHMs and HAA(5)s may be carcinogenic and have linked them to
miscarriages.
Until promulgation of the Stage 1 D/DBP Rule, small
surface-water systems in the United States have been exempt from federal EPA
limits on TTHMs and HAA(5)s in their treated water. Compliance now is required
by November 2003. By meeting the rule's specifications, companies can be
well-positioned to help affected communities get ready for the more stringent
regulations.
The testing was performed by the University of Alaska, in
cooperation with the University of New Hampshire, which is a qualified field
testing organization under the ETV program.
For treating small surface-water flows (more than 1,000
gal/day), the easy-to-clean tubular membranes of the Fyne process may be a
better choice for small communities among higher-maintenance spiral membrane
systems, says David Pearson, general manager at PCI North American. "Using
tubular nanofiltration membranes, the Fyne process can be run with minimal
operator intervention and it requires little to no source-water pretreatment
and extremely infrequent chemical cleaning.
"Spiral membranes require frequent chemical cleaning or
expensive pretreatment on these organic waters, and then there is the issue of
cleaning-chemical disposal," explains Pearson. "But the surface of
the tubular membranes of the Fyne process can be kept clean with foam balls, so
the system doesn't need any real maintenance for several months." This,
automated, "foam ball" cleaning cycle periodically forces foams balls
through the tubular membranes, loosening accumulated material and removing it
from the system. PCI offers complete water-treatment packages, including
containerized plants, and also can provide remote monitoring of system
performance.
About The Author: PCI Membrane Systems offers complete water treatment packages including containerized plants, and also can provide remote monitoring of system performance. In addition to tubular membranes for liquids containing suspended or colloidal materials, PCI also
