A comprehensive summary of dechloramination technologies is currently not available, and therefore a
literature review was undertaken with the objectives of recommending the most feasible and cost-effective
dechloramination alternative and presenting a conceptual design of dechloramination process
for treatment of the filter backwash and filter-to-waste wastewater.
The dechloramination alternatives examined in this study include: dechloramination with passive nonchemical
methods; dechloramination using regular dechlorination chemicals; dechloramination
with activated carbon filters; dechloramination with UV light; dechloramination with breakpoint
chlorination and dechlorination; and, dechloramination using proprietary dechloraminators.
Dechloramination using a regular dechlorination chemical, such as sodium bisulfite, was recommended
as the most feasible and cost-effective alternative for chloramine removal from Evansville WFP filter
backwash and filter-to-waste process wastewater. Preliminary design of the dechloramination system
is summarized in this paper following a characterization of the process wastewater flows, pH, and
free and combined chlorine concentrations. As ammonia is released as a byproduct of the chemical
dechloramination process, the concentration of un-ionized ammonia (which is toxic to many aquatic
organisms) under the worst case scenario of total ammonia nitrogen release was evaluated under
different pH and temperature conditions to assess its potential adverse effects on the receiving waters and aquatic organisms. Methods for minimizing the concentrations of un-ionized and total ammonia
nitrogen, should future plant discharge permit set such limits, are also discussed. Includes 15 references, tables, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 1.3 MB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 64 |
| Published : | 11/01/2009 |
