Modelling Simulation And Control Of Urban Wastewater Systems

by Professor Poul Harremoes Environmental engineering has been a discipline dominated by empirical approaches to engineering. Historically speaking, the development of urban drainage structures was very successful on the basis of pure empiricism. Just think of the impressive structures built by the Romans long before the discipline of hydraulics came into being. The fact is that the Romans did not know much about the theories of hydraulics, which were discovered as late as the mid-1800s. However, with the Renaissance came a new era. Astronomy (Galileos) and basic physics (Newton) started the scientific revolution and in the mid-1800s Navier and Stokes developed the application of Newtons laws to hydrodynamics, and later, St. Venant the first basic physics description of the motion of water in open channels. The combination of basic physical understanding of the phenomena involved in the flow of water in pipes and the experience gained by "trial and error", the engineering approach to urban drainage improved the design and performance of the engineering drainage infrastructure. However, due to the mathematical complications of the basic equations, solutions were available only to quite simple cases of practical significance until the introduction of new principles of calculation made possible by computers and their ability to crunch numbers. Now even intricate hydraulic phenomena can be simulated with a reasonable degree of confidence that the simulations are in agreement with performance in practice, if the models are adequately calibrated with sample performance data.

A considerable amount of scientific evidence has been collected leading to the conclusion that urban wastewater components should be designed as one integrated system, in order to protect the receiving waters cost-effectively. Moreover, there is a need to optimize the design and operation of the sewerage network and wastewater treatment plant (WwTP) considering the dynamic interactions between them and the receiving waters. This book introduces a method called Model Based Design and Control (MoDeCo) for the optimum design and control of urban wastewater components. The book presents a detailed description of the integration of modelling tools for the sewer, the wastewater treatment plants and the rivers. The complex modelling structure used for the integrated model challenge previous applications of integrated modelling approaches presented in scientific literature. The combination of modelling tools and multi-objective evolutionary algorithms demonstrated in this book represent an excellent tool for designers and managers of urban wastewater infrastructure. This book also presents two alternatives to solve the computing demand of the optimization of integrated systems in practical applications: the use of surrogate modelling tools and the use of cloud computer infrastructure for parallel computing.

FROM THE PREFACE Dynamic modeling, computer simulation, and modern control systems are valuable tools for use in both the design and operation of dynamic systems. From the "tools" point of view, this book is designed to show practicing engineers how to develop models capable of describing dynamic behavior and how to "solve" these models using computer simulation. The basic principles of process control are also presented so that the effects of different control systems on dynamic behavior can be established by computer simulation.

The series Advances in Industrial Control aims to report and encourage technology transfer in control engineering. The rapid development of control technology has an impact on all areas of the control discipline. New theory, new controllers, actuators, sensors, new industrial processes, computer methods, new applications, new philosophies ..., new challenges. Much of this development work resides in industrial reports, feasibility study papers and the reports of advanced collaborative projects. The series offers an opportunity for researchers to present an extended exposition of such new work in all aspects of industrial control for wider and rapid dissemination. The water and wastewater industry has undergone many changes in recent years. Of particular importance has been a renewed emphasis on improving resource management with tighter regulatory controls setting new targets on pricing, industry efficiency and loss reduction for both water and wastewater with more stringent environmental discharge conditions for wastewater. Meantime, the demand for water and wastewater services grows as the population increases and wishes for improved living conditions involving, among other items, domestic appliances that use water. Consequently, the installed infrastructure of the industry has to be continuously upgraded and extended, and employed more effectively to accommodate the new demands, both in throughput and in meeting the new regulatory conditions. Investment in fixed infrastructure is capital-intensive and slow to come on-stream. One outcome of these changes and demands is that the industry is examining the potential benefits of, and in many cases using, more advanced control systems.

The Most Complete, Up-to-Date Guide to Process Modeling Methods and Protocols Fully revised to cover the latest advances in the field, Wastewater Treatment Process Modeling, Second Edition, explains general modeling concepts and terminology and offers practical details on how to use process models for the design and operation of small, medium, and large water resource recovery facilities. This Water Environment Federation manual describes each step of the modeling process, including the fundamental math required, overviews of existing models and when to use them, modeling protocols, and how to interpret data. The detailed information in this authoritative volume helps to ensure that process models are developed, used, and documented correctly. Coverage includes: History of process modeling Modeling fundamentals Unit process model descriptions Process modeling tools Dedicated experiments and tools Overview of available modeling and simulation protocols Project definition Building a facility model Using models for design, optimization, and control

Urban population growth dramatically alters material and energy fluxes in the affected areas, with concomitant changes in landscape, altered fluxes of water, sediment, chemicals and pathogens and increased releases of waste heat. These changes then impact on urban ecosystems, including water resources and result in their degradation. Such circumstances make the provision of water services to urban populations even more challenging. Changing weather patterns, rising temperature and large variations in precipitation contr- ute to increased damages, caused by weather related disasters, including floods. Ones of the major contributors to increasing flood peaks are land use changes and particularl- urban development. Consequently, there is a need to look for low environmental impact land development and to manage runoff in urban areas by storm water management. Much progress in the management of urban waters has been achieved in the most - vanced jurisdictions, but much more remains to be done. In this respect the EC Water Framework Directive can provide some guidance. Urban water management issues are particularly important in the countries in transition in Central and Eastern Europe. During the last decade political, economical and social changes in the countries under transition have influenced almost every element of the public sector, including water services. There is an urgent need for exchange of information among various countries on this issue and for identification of best approaches to achieving this transition.

This book features expert contributions on key sustainability aspects of urban water management in Chinese agglomerations. Both technical and institutional pathways to sustainable urban water management are developed on the basis of a broad, interdisciplinary problem analysis.