The objective of this paper is to
examine the control of precursors for various emerging N- and C-DBPs and how that compares
with the control of THM precursors.
A full-scale survey of 16 U.S. drinking water treatment plants (DWTPs) was conducted
in 2006 and 2007 (each plant was sampled once or twice). The focus of this study was on
DWTPs that treated wastewater and/or algal impacted water, which are sources of
precursors for N-DBPs. All of the DWTPs in this study treated surface water. DWTPs
sampled used a range of treatment processes (coagulation, lime softening, ultrafiltration,
filtration with granular activated carbon [GAC]) and disinfectants (chlorine [Cl<sub>2</sub>], chlorine
dioxide, chloramines [NH<sub>2</sub>Cl], ozone, UV). The sample sites were in various geographical
regions of the U.S.
Analytical parameters are detailed in this paper, along with study results. A summary of the study indicated that utilities have installed and modified treatment practices to control the formation of
regulated DBPs (e.g., THMs). In this study, DBPFP tests were conducted on samples from
different points in the surveyed plants. These tests not only showed the removal or destruction
of DBP precursors with various unit processes, but the contribution of certain processes to
increasing DBPFP (e.g., use of certain polymers increasing NDMAFP; ozonation increasing
TCNMFP).
In order to balance the control of regulated DBPs with that of emerging DBPs of health concern,
utilities will need to optimize a series of various unit processes to minimize the formation of a
wide range of DBPs. Includes 20 references, tables, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 770 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 33 |
| Published : | 11/01/2008 |
