Optimization of A²O BNR Processes Using ASM and EAWAG Bio‐P Models: Model Performance

Abstract

This paper presents the performance of an optimization model for a biological nutrient removal (BNR) system using the anaerobic-anoxic-oxic (A(2)O) process. The formulated model simulates removal of organics, nitrogen, and phosphorus using a reduced International Water Association (IWA) Activated Sludge Model #3 (ASM3) model and a Swiss Federal Institute for Environmental Science and Technology (EAWAG) Bio-P module. Optimal sizing is attained considering capital and operational costs. Process performance is evaluated against the effect of influent conditions, effluent limits, and selected parameters of various optimal solutions with the following results: an increase of influent temperature from 10 degrees C to 25 degrees C decreases the annual cost by about 8.5%, an increase of influent flow from 500 to 2500 m(3)/h triples the annual cost, the A(2)O BNR system is more sensitive to variations in influent ammonia than phosphorus concentration and the maximum growth rate of autotrophic biomass was the most sensitive kinetic parameter in the optimization model.

Optimization Methodology for High COD Nutrient-Limited Wastewaters Treatment Using BAS Process

“…Once MBBR behaviour is simulated until steady-state, the rest of the process is optimized for each alternative using three different index as objective functions: total cost index, effluent quality index or/and operating cost index as objective functions. The optimization of the BAS process is done by the software General Algebraic Modeling System (GAMS) using CONOPT as NLP algorithm (El Shorbagy et al 2013).…”