Divide and conquer is a phrase usually associated with political or military strategy.
It could also describe nutrient removal improvements at the Cookeville (Tennessee) Wastewater Treatment Plant, where operational changes to the oxidation ditches have enabled the plant to meet more stringent permit requirements.
The changes involved dividing each of four ditches into separate vertical zones and turning them on and off to create anoxic conditions to facilitate nitrification-denitrification. Tom Graham, plant superintendent, credits the idea to his assistant, John Buford.
“The state had actually hired a consultant who came in and tried different methods here but couldn’t find a solution with the
