BATCH TEST PROCEDURES AS TOOLS FOR CALIBRATION OF THE ACTIVATED-SLUDGE MODEL - A PILOT-SCALE DEMONSTRATION

Various mathematical models have been developed to facilitate the desi gn and operation of biological nutrient removal plants. Proper calibra tion of such models can be a difficult task due to the large number of variable process coefficients. The paper describes a strategy for mod el calibration based on batch characterizations of wastewater and acti vated sludge biomass and demonstrates its applicability through modell ing of the process dynamics in a highly dynamic activated sludge pilot plant. A comprehensive experimental programme was undertaken comprisi ng batch characterizations of readily degradable and easily hydrolysab le COD in influent wastewater, maximum and endogenous process rates fo r functional microorganism groups in the activated sludge, and half-sa turation process constants to describe the impact of oxygen on nitrifi cation and denitrification. An on-line measurement of ammonia and nitr ate and nitrite using a Flow Injection Analysis System was conducted f or two consecutive days to study the process dynamics in a BioDenitro pilot plant for two parallel activated sludge process tanks. It was po ssible to closely mimic the dynamics of the nitrogen removal processes in the two tanks based on the model calibration strategy using wastew ater and biomass characteristics determined in batch experiments. (C) 1998 IAWQ. Published by Elsevier Science Ltd.