Probabilistic Modeling of Two-Stage Biological Nitrogen Removal Process: Conditions for Enhanced Process Certitude

Autor: Benjamin S. Magbanua, Ayanangshu Dey
Rok vydání: 2010
Předmět:
Zdroj: Environmental Engineering Science. 27:1035-1042
ISSN: 1557-9018
1092-8758
DOI: 10.1089/ees.2010.0036
Popis: In a conventional two-stage biological nitrogen removal (BNR) process, the extent of uncertainty associated with different operating parameters (e.g., solids retention time, internal recirculation ratio, anoxic hydraulic retention time [HRT], total HRT, and sludge recycle ratio) was evaluated by simulation with Activated Sludge Model no 1. Variability in the values of kinetic parameters was incorporated in performing stochastic simulations by adopting the influent biodegradable chemical oxygen demand–to–total kjeldahl nitrogen (COD:TKN) ratio of 10, an important determinant of BNR performance. Simulation results predicted maximum level of certitude for effective nitrogen removal at 3-h anoxic HRT (and 12-h total HRT). Appreciable rise in process certitude for nitrogen removal was indicated as solids retention time was increased from 5 to 20 days. No noticeable rise in confidence level could be achieved for meeting stipulated treatment targets by increasing internal recycle (for nitrate recirculat...
Databáze: OpenAIRE