Several water systems throughout the United States failed to
comply with the Stage 1 Disinfectants/Disinfection Byproduct Rule (D/DBP
Rule) this past year. With the Stage 2 D/DBP Rule scheduled to be
promulgated by the end of this year (2005), even more utilities will be out of
compliance with DBP regulations in the future unless significant operational
or treatment changes are implemented. Conversion to chloramines has
been the fall-back for many utilities. However, chloramines are not
necessarily the answer for all utilities, especially those concerned about
security issues, wastewater nitrogen levels, increased distribution system
operations, health affects associated with nitrogenous DBPs, or siting
ammonia storage and feed facilities. The purpose of this paper is to briefly
discuss DBP control options and present results from a case study that
bought DBPs under control without switching to chloramines. The control
options examined include:
lowering applied chlorine dose;
altering pH in the distribution system;
implementing operational changes to decrease detention time in the
distribution system;
using chlorine dioxide as a pre-oxidant; and,
converting to chloramines.
The study demonstrated that THM and HAA levels can be reduced to
varying degrees (10 to 40%) depending on the control option employed and
the characteristics of the source water. Interestingly, all options reduced
THM and HAA levels to different extents. For example, chlorine dioxide
reduced THM levels by as much as 40%, but usually had very little effect on
HAA levels, whereas lowering the applied chlorine dose had a greater effect
on HAA levels. Includes tables, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 760 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 20 |
| Published : | 11/01/2005 |
