In deciding if denitrification is a possibility looking at the influent you want at least around a 3:1 nitrogen ratio. There are many other factors involved, but this is all I'm aware of based in the influent.

Most importantly you need a true anoxic zone and a soluble BOD: nitrate of around 8:1 in that zone with the proper retention time.

best regards,

Ryan

arunmoozhikulam:

I agree with sludgefather's carbon to nitrogen ratio of 3:1. However, this isn't the whole story. The BOD has to be readily degradable, soluble BOD that can drive denitrification. Many plants I work with lack this component and don't denitrifiy well (and have to add methanol). You need the BOD to be readily degradable and soluble. Yu can measure the soluble BOD by first filtering the influent sample through a 0.5 um pore-sized membrane filter and testing the BOD of the clear filtrate. Then you need the 3:1 ratio based on soluble BOD.

Hope that this helps.

arunmoozhikulam:

Total Kjeldahl Nitrogen (TKN) is ammonia plus organic nitrogen. The ammonia will all be converted to nitrate but not the organic nitrogen. This is variable. Assume above one-half to two thirds conversion of the organic nitrogen to ammonia. Start your carbon feed at 2:1 soluble BOD to TKN, then increase this as necessary to get the desired denitrification.

Hope that this helps.