W. Bailey et al., LARGE-SCALE NITROGEN REMOVAL DEMONSTRATION AT THE BLUE-PLAINS-WASTE-WATER-TREATMENT-PLANT USING POSTDENITRIFICATION WITH METHANOL, Water science and technology, 38(1), 1998, pp. 79-86
Citations number
2
Categorie Soggetti
Water Resources","Environmental Sciences","Engineering, Civil
The Chesapeake Bay Agreement of 1987 calls for an overall reduction in
nutrient loading of forty percent of 1985 levels by the year 2000. Si
gnatories to the agreement include the states located in the Bay's wat
ershed and the District of Columbia. The District's 16.2 m(3)/sec (370
mgd) Blue Plains Regional Wastewater Treatment Plant is the single, l
argest point source of nitrogen load to the Bay, discharging approxima
tely 18 metric tons per day. In an effort toward meeting the nitrogen
reduction goal, a post-denitrification demonstration study was recentl
y begun to access its potential for long-term implementation. The deni
trification demonstration project involves operating half of the nitri
fication facilities in a nitrification-denitrification mode using meth
anol as a carbon source for post-denitrification. The other half conti
nues operation in a nitrification-only mode as a control. The post-den
itrification process was selected for demonstration because it utilize
s existing facilities and may offer substantial long-term cost savings
. Objectives of the study are to demonstrate the process without a neg
ative impact on effluent quality, to verify performance and capacity,
to determine the stability and limitations of the project, and to comp
are the process to other nitrogen-removal technologies. Thus far, the
process has been successful in removing nitrogen despite problems with
phosphorus limitation and with the settling characteristics of the de
nitrification sludge. It is believed that insufficient phosphorus avai
lability has been responsible for problems associated with settling, s
ludge yield, methanol use, and denitrification rates. Recently, phosph
orus input to the denitrification process has been increased by reduci
ng metal salt addition in upstream processes and preliminary results h
ave been promising. If performance criteria are achieved without sacri
ficing plant capacity, the process will be continued at full scale. (C
) 1998 Published by Elsevier Science Ltd. All rights reserved.