Dear Phillipe, dissolved inorganic N (NH4, NO2, NO2) which has reliance to WWT processes; I have no idea about non-biodegradable inorganic N. The name of the game here is TKN; organic N. Microfiltration has limitations in removal of nitrogen fractions. We have difficulties in reaching a total N of 10 mgN/L in one of MBR facilities? What is the actual source of organic N is not easy? So, assuming of 2 mg N as TKN in the effluent (German DWA approach in ATV-A 131) is just to make the life of the process engineer easy in doing a N mass balance. So, organic N can be non biodegradable if of biological origin as intermediate metabolites or of unknown industrial waste streams.

Published by

Dear Phillipe, dissolved inorganic N (NH4, NO2, NO2) which has reliance to WWT processes; I have no idea about non-biodegradable inorganic N. The name of the game here is TKN; organic N. Microfiltration has limitations in removal of nitrogen fractions. We have difficulties in reaching a total N of 10 mgN/L in one of MBR facilities? What is the actual source of organic N is not easy? So, assuming of 2 mg N as TKN in the effluent (German DWA approach in ATV-A 131) is just to make the life of the process engineer easy in doing a N mass balance.

So, organic N can be non biodegradable if of biological origin as intermediate metabolites or of unknown industrial waste streams.