Modelling the degradation of low concentration pollutants in MBRs

Beschreibung

Quantitative mathematical modelling of wastewater treatment (as e.g. the well known IAWQ-ASM models) is a powerful tool allowing optimal design and operation of municipal treatment systems. However standard models operate with integral system state-variables (such as COD), do not enter into further details concerning separate organic and inorganic compounds with particular environmental impact and cannot be directly applied to more complex situations such as industrially polluted wastewaters. To achieve improved understanding and optimization of biological wastewater treatment of specific pollutants requires quantitative modelling going beyond the integral approach. In this presentation we address the parameter estimation for a novel biokinetic degradation model in MBR wastewater treatment systems. It builds upon standard biokinetic model approaches and aims to describe the degradation of low-concentration organic substances by specialised minority bacterial sub-populations. In particular we focus on the degradation of P3 (persistent polar pollutant) compounds. We have developed an experimental protocol aiming at the estimation of the basic biokinetic parameters Ks,P3 (saturation constant of P3-competent biomass), µmax,P3 (maximum growth rate of P3-competent biomass), the ratio X0,P3/YP3 (X0,P3 is the initial specialised biomass concentration and YP3 is the growth yield of P3-competent biomass) and the decay rate bP3 of the specialised biomass. This approach neglects any possible interdependencies between specific biomass growth on normal and P3 substances. We have designed two basic types of short-term batch experiments to determine these quantities. The mathematical approach to these experiments and their results for NDSA and BTSA as model P3 compounds will be presented and discussed. The MBR model with the biokinetic parameters determined in this experimental setup will be used to optimize MBR operation with respect to the removal of polar, hardly degradable organic pollutants.

Zeitraum	12 Dez. 2005
Ereignistitel	PTHREE Workshop Advanced wstewater technologies fort he removal of organic contaminants and potential impact of the water framework directive
Veranstaltungstyp	Sonstiges
Bekanntheitsgrad	International