PARENT SESSION
16 - Oil Pollution & Biodegradation
8:00 AM to 6:30 PM, Monday, 13 May 2002
Exhibition Area

(16-25) WEST, a general tool for dynamic modelling and simulation of biodegradation processes.

De Pauw, Dirk^*,1, Carvalho, Gilda², Nopens, Ingmar¹, Verdonck, Frederik¹, Meirlaen, Jurgen¹, Vanrolleghem, Peter¹, ¹ BIOMATH, Ghent University, Ghent, Belgium² Centro de Engenharia Biológica e Qumica, Lisboa, Portugal

ABSTRACT- Biodegradation processes of chemicals in the environment can often be described by dynamic non-linear models (e.g. Monod). The problem that a lot of researchers face, is the lack of suitable modelling and simulation tools to solve these models. Therefore, the modelling and simulation tool WEST is proposed. It is able to solve sets of algebraic and differential equations using several integration algorithms. WEST has an extensive model database and user defined models can be added using its own simple modelling language called MSL (model specification language). Following toolboxes are also included: parameter estimation with confidence information, sensitivity analysis and experimental design. Using this software tool several biodegradation processes have been studied with success. This poster will focus on two applications. First, biodegradation of non-ionic surfactants was studied in a sequencing batch reactor (SBR). The surfactant molecule and its metabolites were considered to be degraded by different bacterial or enzymatic consortia, with different associated kinetic parameters. Therefore a fractionated degradation model was used. A second application is the 10-day window criterion for determining biodegradability of new chemicals. In this study Monod and double Monod models where fitted to biodegradation curves obtained from ready biodegradation tests. From these models estimates of biodegradation parameters for different chemicals where obtained. This application also resulted in the proposal of an alternative criterion for biodegradability. Besides biodegradation, WEST is also used in other fields like wastewater treatment and river/sewer modelling.

Key words: biodegradation, modelling, simulation, tool