Simulations of reactive settling of activated sludge with a reduced biokinetic model

The Activated Sludge SIMulation program ASIM is introduced as a didactic tool to be used in design courses for the simulation of the dynamic behaviour of modern nutrient removal activated sludge systems. It allows for free definition of the biokinetic model, the flow scheme, process control strategies and load variation. Its user interface is simple enough to be used in the classroom but powerful enough to support even professional work. The most difficult aspect of ASIM is the preparation of the biokinetic model (transformation processes) to be used. A systematic use of stoichiometric conservation principles simplifies this task and at the same time reduces the number of empirical parameters. The practical application of conservation principles for charge, elements and theoretical COD is presented in detail. Composition equations are introduced as a link to the wastewater treatment plant reality.

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Mathematical model for soluble carbonaceous substrate biosorption

Water Science & Technology ◽

10.2166/wst.1995.0075 ◽

1995 ◽

Vol 31 (2) ◽

pp. 67-77 ◽

Cited By ~ 5

Author(s):

Libor Novák ◽

Luis Larrea ◽

Jiri Wanner

Keyword(s):

Mathematical Model ◽

Activated Sludge ◽

Treatment Plant ◽

Synthetic Wastewater ◽

Dynamic Tests ◽

Cultivation Conditions ◽

Biokinetic Model ◽

Kinetic Tests ◽

Conventional Models ◽

Adsorption Desorption

An activated sludge mathematical model for soluble carbonaceous substrate biosorption has been developed. The model allows the soluble COD fractions in biological reactors of a wastewater treatment plant and/or in batch cultivations to be predicted more precisely than by using conventional models. Special attention was paid to interactions between the biokinetic model structure and population dynamics of microorganisms in activated sludge. The model was developed using observations made on a synthetic wastewater which was dosed to a lab-scale, continuously operated plant with the D-R-D-N configuration. The development of the model advanced through several biokinetic models which resulted in a final version of the biosorption model. The model is constructed on a matrix structure. Adsorption, desorption and hydrolysis kinetics are incorporated into the model. Experimental results from batch cultivations carried out under anoxic and oxic conditions as well as some dynamic tests carried out with the continuously operated system served for the model calibration. Simulations of a wide diversity of kinetic tests demonstrate that the model is able to accurately predict the soluble COD under different cultivation conditions.

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Practical identifiability of a biokinetic model of activated sludge respiration

Water Research ◽

10.1016/0043-1354(95)00105-t ◽

1995 ◽

Vol 29 (11) ◽

pp. 2561-2570 ◽

Cited By ~ 98

Author(s):

P Vanrolleghem

Keyword(s):

Activated Sludge ◽

Practical Identifiability ◽

Biokinetic Model

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Bulking in Activated Sludge Systems: A Qualitative Simulation Model for Sphaerotilus natans, Type 021N and Type 0961

Water Science & Technology ◽

10.2166/wst.1992.0427 ◽

1992 ◽

Vol 26 (3-4) ◽

pp. 473-482 ◽

Cited By ~ 10

Author(s):

J. Kappeler ◽

W. Gujer

Keyword(s):

Activated Sludge ◽

Simulation Model ◽

Strong Influence ◽

Competition Model ◽

Qualitative Simulation ◽

Sphaerotilus Natans ◽

Reactor Configuration ◽

Biokinetic Model ◽

Filamentous Microorganisms ◽

Activated Sludge Systems

A biokinetic model which includes a flocforming and three common filamentous microorganisms (Sphaerotilus natans, Type 021N, Type 0961) is introduced. With this competition model which accords with a variety of experimental observations, different bulking phenomena are explained. It is demonstrated that not only the well known facts such as reactor configuration, readily biodegradable substrate and temperature exert a strong influence on bulking behaviour, but also the influent slowly biodegradable substrate as well as inoculating biomass. Therefore it can be concluded that the performance of primary settling tanks plays an important part in bulking.

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Activated sludge modelling: development and potential use of a practical applications database

Water Science & Technology ◽

10.2166/wst.2011.368 ◽

2011 ◽

Vol 63 (10) ◽

pp. 2164-2182 ◽

Cited By ~ 30

Author(s):

H. Hauduc ◽

L. Rieger ◽

T. Ohtsuki ◽

A. Shaw ◽

I. Takács ◽

...

Keyword(s):

Activated Sludge ◽

Practical Experience ◽

Model Parameters ◽

Practical Applications ◽

Biokinetic Model ◽

Starting Point ◽

Technical Report ◽

Typical Parameter ◽

Parameter Values ◽

Activated Sludge Models

This study aims at synthesizing experiences in the practical application of ASM type models. The information is made easily accessible to model users by creating a database of modelling projects. This database includes answers to a questionnaire that was sent out to model users in 2008 to provide inputs for a Scientific and Technical Report of the IWA Task Group on Good Modelling Practice – Guidelines for use of activated sludge models, and a literature review on published modelling projects. The database is analysed to determine which biokinetic model parameters are usually changed by modellers, in which ranges, and what values are typically used for seven selected activated sludge models. These results should help model users in the calibration step, by providing typical parameter values as a starting point and ranges as a guide. However, the proposed values should be used with great care since they are the result of averaging practical experience and not taking into account specific parameter correlations.

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Modelling Population Dynamics in Activated Sludge Systems

Water Science & Technology ◽

10.2166/wst.1992.0116 ◽

1992 ◽

Vol 25 (6) ◽

pp. 93-103 ◽

Cited By ~ 10

Author(s):

W. Gujer ◽

J. Kappeier

Keyword(s):

Population Dynamics ◽

Activated Sludge ◽

Residence Time ◽

Operating Conditions ◽

Organic Substrates ◽

Flotation Process ◽

Biokinetic Model ◽

And Behavior ◽

Activated Sludge Systems

A biokinetic model is introduced which allows for the prediction of the development of flocforming, filamentous and ‘Nocardia' type microorganisms in aerobic activated sludge systems with a variety of different flowschemes and operating conditions. The model is based on the competition of the organisms for different organic substrates. For ‘Nocardia' a flotation process is introduced which allows for a longer residence time of these organisms as compared to the SRT. The model predicts activated sludge composition and behavior in accordance with a variety of experimental observations.

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