The Effects of Prefermentation Upon Biological Nutrient Removal Systems with Septic, COD Limited Influent Wastewater

The objective of this NSF sponsored research was to provide a controlled comparison of identical continuous flow pilot-scale BNR processes both with and without prefermentation in order to provide a stronger, more quantitative, technical basis for design engineers to determine the potential benefits of prefermentation to EBPR in treating a domestic, COD-limited septic wastewater. In addition, the even less understood effect of prefermentation on denitrification kinetics and anoxic P uptake was studied and quantified. Other aspects of BNR performance (e.g. settleability, etc…) which might change due to use of prefermentation were also addressed. In addition, the biokinetic parameters necessary to successfully model both the activated sludge systems and the prefermenter are being determined. Identification of these biokinetic parameters may help identify changes in influent characteristics other than just VFA changes.