Biological Nitrogen and Phosphorus Removal in Oxidation Ditch and High Nitrate Recycle Systems

Published:

August 1, 1990

Originator:

Chesapeake Bay Program

EPA Number:

903-R-01-001

Full scale process modifications were conducted in an oxidaation ditch system to understand the kinetics of biological nitrogen and phosphorus removal in activated sludge systems which may use high nitrate or internal recycles. Design parameters and operating strategies with multiple control parameters were evaluated over a two-year period to helpincrease the efficiency of year round biological nutrient removal in temperature climates. The full sscale evaluation has helped identify the extent of nitrogen and phosphorus removal which can be achieved, and the corresponding changes in the kinetic of reactions when nitrate recycle rates are increased to enhance denitrification in activated sludge removal