Citation:
Ana Soares, Pantelis Kampas, Sarah Maillard, Elizabeth Wood, Jon Brigg, Martin
Tillotson, Simon A. Parsons, Elise Cartmell, Comparison between disintegrated
and fermented sewage sludge for production of a carbon source suitable for
biological nutrient removal, Journal of Hazardous Materials, Volume 175, Issues
1-3, 15 March 2010, Pages 733-739
Abstract:
There is a need to investigate processes that enable sludge re-use while
enhancing sewage treatment efficiency. Mechanically disintegrated thickened
surplus activated sludge (SAS) and fermented primary sludge were compared for
their capacity to produce a carbon source suitable for BNR by completing
nutrient removal predictive tests. Mechanically disintegration of SAS using a
deflaker enhanced volatile fatty acids (VFAs) content from 92 to 374 mg l−1
(4.1-fold increase). In comparison, primary sludge fermentation increased the
VFAs content from 3.5 g l−1 to a final concentration of 8.7 g l−1 (2.5-fold
increase). The carbon source obtained from disintegration and fermentation
treatments improved phosphate (PO4-P) release and denitrification by up to 0.04
mg NO3-N g−1 VSS min−1 and 0.031 mg PO4-P g−1 VSS min−1, respectively, in
comparison to acetate (0.023 mg NO3-N g−1 VSS min−1and 0.010 mg PO4-P g−1 VSS
min−1). Overall, both types of sludge were suitable for BNR but disintegrated
SAS displayed lower carbon to nutrient ratios of 8 for SCOD:PO4-P and 9 for
SCOD:NO3-N. On the other hand, SAS increased the concentration of PO4-P in the
settled sewage by a further 0.97 g PO4-P kg−1 SCOD indicating its potential
negative impact towards nutrient recyc