Wastewater treatment plants (WWTPs) that discharge into nutrient-sensitive watersheds face strict new regulations requiring enhanced removal of total nitrogen (TN) and total phosphorus (TP), often with levels of TN at or below 3 mg/L.
To provide sufficient denitrification to reduce to these levels, many of these facilities will require the addition of supplemental carbon to the second anoxic zones of their biological nutrient removal (BNR) tanks and denitrification filters. Methanol historically has been used for denitrification at WWTPs, but for various reasons, many utilities are considering alternative carbon sources.
Two mid-Atlantic municipal WWTPs conducted full-scale evaluations of supplemental carbon alternatives to evaluate whether these products were effective in meeting their low-effluent nitrogen discharge limits. Bench-scale experiments were also conducted.
© Copyright 2012 Hazen and Sawyer.