Methods For Wastewater Characterization In Activated Sludge Modelling

Mathematical modeling is a useful tool for the design, analysis and control of wastewater treatment systems. The activated sludge process is one of the most common processes used in wastewater treatment, and therefore is a particularly important candidate for the application of mathematical models. In the 1980s, a task group organized by the International Association on Water Quality (IAWQ) developed a conceptual model of the activated sludge process, which has become an industry-wide standard for the development of computer-based activated sludge models. A recent version of the IAWQ model incorporates 19 components, 17 processes, and numerous rate and stoichiometric coefficients. It is difficult and costly to quantify all of the necessary coefficients for any given application of the model; consequently, it is important to identify the most critical wastewater and biomass components and the relevant coefficients to be quantified for the most common uses of the model. It is also important to provide guidance to potential model users on the use of default and/or estimated values for the remaining parameters.

This book has been produced to give a total overview of the Activated Sludge Model (ASM) family at the start of 2000 and to give the reader easy access to the different models in their original versions. It thus presents ASM1, ASM2, ASM2d and ASM3 together for the first time. Modelling of activated sludge processes has become a common part of the design and operation of wastewater treatment plants. Today models are being used in design, control, teaching and research. Contents ASM3: Introduction, Comparison of ASM1 and ASM3, ASM3: Definition of compounds in the model, ASM3: Definition of processes in the Model, ASM3: Stoichiometry, ASM3: Kinetics, Limitations of ASM3, Aspects of application of ASM3, ASM3C: A Carbon based model, Conclusion ASM 2d: Introduction, Conceptual Approach, ASM 2d, Typical Wastewater Characteristics and Kinetic and Stoichiometric Constants, Limitations, Conclusion ASM 2: Introduction, ASM 2, Typical Wastewater Characteristics and Kinetic and Stoichiometric Constants, Wastewater Characterization for Activated Sludge Processes, Calibration of the ASM 2, Model Limitations, Conclusion, Bibliography ASM 1: Introduction, Method of Model Presentation, Model Incorporating Carbon Oxidation Nitrification and Denitrification, Characterization of Wastewater and Estimation of Parameter Values, Typical Parameter Ranges, Default Values, and Effects of Environmental Factors, Assumptions, Restrictions and Constraints, Implementation of the Activated Sludge Model Scientific and Technical Report No.9

The use of models in activated sludge design and operation is increasing, with a similar trend seen in education. Starting with the original IAWPRC Activated Sludge Model no 1 (ASM1) and the subsequent ASM2 and ASM2D, the first generation of activated sludge models have played an important role in practice. With the development of the latest IWA Activated Sludge Model no 3 further progress has been made, and given the concurrent development of new methods for characterization of biomass and wastewater, this is a field of vigorous activity at present. The fifth Kollekolle Seminar brought together many of the world's leading experts on the activated sludge process, who have been working with activated sludge models in practice and research. The aim, as with previous seminars was to present the latest research findings, putting them into the proper perspective. From this high-quality programme 22 papers have been selected and revised to provide the best collection of papers on the state of the art of activated sludge modeling. Papers cover the following topics: modeling developments; wastewater and biomass characterization and parameter identification; modeling in practices.

Mathematical modelling of activated sludge systems is used widely for plant design, optimisation, training, controller design and research. The quality of simulation studies varies depending on the project objectives, finances and expertise available. Consideration has to be given to the model accuracy and the amount of time required carrying out a simulation study to produce the desired accuracy. Inconsistent approaches and insufficient documentation make quality assessment and comparison of simulation results difficult or almost impossible. A general framework for the application of activated sludge models is needed in order to overcome these obstacles. The genesis of the Good Modelling Practice (GMP) Task Group lies in a workshop held at the 4th IWA World Water Congress in Marrakech, Morocco where members of research groups active in wastewater treatment modelling came together to develop plans to synthesize the best practices of modellers from all over the world. The most cited protocols were included in the work, amongst others from: HSG (Hochschulgruppe), STOWA, BIOMATH and WERF. The goal of the group is to set up an internationally accepted framework to deal with the ASM type models in practice. This framework shall make modelling more straightforward and systematic to use especially for practitioners and consultants. Additionally, it shall help to define quality levels for simulation results, a procedure to assess this quality and to assist in the proper use of the models. The framework will describe a methodology for goal-oriented application of activated sludge models demonstrated by means of a concise guideline about the procedure of a simulation study and some illustrative case studies. The case studies shall give examples for the required data quality and quantity and the effort for calibration/validation with respect to a defined goal. The final report will include an extended appendix with additional information and details of methodologies. Additional features in Guidelines for Using Activated Sludge Models include a chapter on modelling industrial wastewater, an overview on the history, current practice and future of activated sludge modelling and several explanatory case studies. It can be used as an introductory book to learn about Good Modelling Practice (GMP) in activated sludge modelling and will be of special interest for process engineers who have no prior knowledge of modelling or for lecturers who need a textbook for their students. The STR can also be used as a modelling reference book and includes an extended appendix with additional information and details of methodologies. Scientific and Technical Report No. 22

Activated sludge is the most vital wastewater process today. Now, this recent book provides a comprehensive guide to the modelling and design of activated sludge systems. Written by two leaders in the wastewater field, the book presents extensive and up-to-date coverage of all areas in the activated sludge process microbiological basis, reactor kinetics, and design methodologies. The book is organized for easy reference and is ideal as a text or desktop guide.

Mathematical Modelling and Computer Simulation of Activated Sludge Systems – Second Edition provides, from the process engineering perspective, a comprehensive and up-to-date overview regarding various aspects of the mechanistic (“white box”) modelling and simulation of advanced activated sludge systems performing biological nutrient removal. In the new edition of the book, a special focus is given to nitrogen removal and the latest developments in modelling the innovative nitrogen removal processes. Furthermore, a new section on micropollutant removal has been added. The focus of modelling has been shifting in the last years to models that can describe the performance of a whole plant (plant-wide modelling). The expanded part of this new edition introduces models describing the most important processes interrelated with the mainstream activated sludge systems as well as models describing the energy balance, operating costs and environmental impact. The complex process evaluation, including minimization of energy consumption and carbon footprint, is in line with the present and future wastewater treatment goals. By combining a general introduction and a textbook, this book serves both intermediate and more experienced model users, both researchers and practitioners, as a comprehensive guide to modelling and simulation studies. The book can be used as a supplemental material at graduate and post-graduate levels of wastewater engineering/modelling courses.

Industrial pollution is still a major concern and despite its significance, sound and systematic pollution control efforts are very poorly documented. The character and treatability of industrial wastewaters is highly variable and specific for each industrial activity. Biological treatment with activated sludge is the appropriate technology for industrial wastewaters from several major industrial sectors. Industrial Wastewater Treatment by Activated Sludge deals with the activated sludge treatment of industrial wastewaters by considering conceptual frameworks, methodologies and case studies, in a stepwise manner. The issues related to activated sludge treatment, such as biodegradability based characterization, modeling, assessment of stoichiometric and kinetic parameters and design, as well as the issues of industrial pollution control, e.g. in-plant control, effect of pretreatment, etc. are combined in a way to provide a comprehensive and information-rich view to the reader. By doing so, the book supplies an up-to-date reference for industrial wastewater experts and both graduate and undergraduate students. Industrial Wastewater Treatment by Activated Sludge provides a roadmap, describing the methodologies for the treatment of industrial wastewaters from several major sectors, based on a solid theoretical background. Up to now although valuable separate efforts both on activated sludge and industrial wastewater treatment have been presented, an integrated approach that is crucial to practice has not been available. This gap is filled by this book.