Sludge production based on organic matter and nitrogen removal performances

Excess biomass produced during the biological treatment of wastewater requires costly disposal. As environmental and legislative constraints increase, there is considerable impetus for reducing the sludge production. Nowadays, several strategies for minimizing it production are applied but high costs still limit their application in full-scale wastewater treatment plants (WWTPs). On the other hand, biological nutrient removal (BNR) process may have an impact on the sludge production. This paper deals with the effect on the organic matter and nitrogen performances on the sludge production treating urban wastewater. The results demonstrated that the sewage sludge production was reduced between 50 to 60% (0.38 to 0.16 kg VSS·kg⁻¹ COD) while improving the nitrogen removal efficiency from 33% to 79%. Therefore, an efficient way to minimize the sludge production, it is by operating the WWTP in optimal conditions for nutrient removal.