Activated sludge separation problems : theory, control measures, practical experiences / edited by Simona Rossetti, Valter Tandoi and Jiri Wanner.

Format:

Book

Contributor:

Tandoi, Valter, editor.

Rossetti, Simona, editor.

Wanner, Jiří, editor.

Language:

English

Subjects (All):

Sewage--Purification--Activated sludge process.

Sewage.

Physical Description:

1 online resource (324 pages)

Edition:

Second edition.

Place of Publication:

London, England : IWA Publishing, 2017.

Summary:

Activated Sludge Separation Problems: Theory, Control Measures, Practical Experiences, Second Edition, describes the most common activated sludge separation problems and explains the main reasons for the growth of the different filamentous microorganisms in activated sludge. The book summarizes the identification techniques for important groups of activated sludge microorganisms both based on conventional microscopic analysis and using the biological molecular tools available today (FISH and PCR). This new edition, with 70% new and updated material, also provides explanation of basic activated sludge process principles and of parameters necessary for process control and operation. The theory of secondary clarifies is described to the extent necessary for understanding the construction and operation of secondary clarifiers. The activated sludge reactor and secondary clarifies are treated as one system and the interactions are explained. The wide range of experiences around the world is documented and the methods to avoid the proliferation of these organisms are presented and critically reviewed.Activated Sludge Separation Problems consists of six chapters, presenting up-to-date technical and scientific aspects of these processes. The new edition also features an extended list of literature references for further reading. The book will be a valuable help for students of environmental engineering, wastewater specialists, plant operators and designers of activated sludge plants. It is also useful for specialists in wastewater operation laboratories, especially for those studying activated sludge separation properties.

Contents:

Cover

Copyright

Dedication

Contents

Abbreviations

List of Contributors

Preface

Chapter 1: Wastewater characterization

1.1 Introduction

1.2 Gross Parameters

1.3 Physical Properties

1.4 Organic Matter

1.5 Inorganic Matter

1.6 Micropollutants

1.7 Biodegradability

1.7.1 COD, Nitrogen and phosphorus fractionation

1.7.2 Evaluation methods

References

Chapter 2: The microbiology of the activated sludge process

2.1 Introduction

2.2 Microorganisms in Activated Sludge

2.2.1 Bacteria: cell structure

2.2.2 Inclusions

2.3 The Identification of Bacteria

2.3.1 Conventional taxonomy

2.3.2 Molecular taxonomy

2.3.3 Molecular characterization of mixed biomass

2.4 Filamentous Bacteria

2.5 Microthrix parvicella

2.5.1 Identification of M. parvicella

2.5.2 Physiology of 'Candidatus M. parvicella'

2.6 Thiothrix

2.7 Nostocoida limicola

2.8 Polyphosphate Accumulating Organisms (PAO)

2.9 Glycogen Accumulating Organisms (GAO)

2.10 Nitrifiers

2.11 Denitrifiers

Chapter 3: Activated sludge separation problems

3.1 Introduction

3.2 'Well-settling' Activated Sludge

3.2.1 Requirements

3.2.2 Microscopic features of well settling activated sludge

3.3 Activated Sludge Separation Problems

3.3.1 Poor floc microstructure

3.3.2 Poor floc macrostructure

3.3.3 Other reasons

3.4 Summary

Acknowledgment

Chapter 4: Aeration tank and secondary clarifier as one system

4.1 Introduction

4.2 Aeration Tank and Secondary Clarifier Interactions

4.2.1 Activated sludge process

4.2.2 Secondary clarifier

4.2.3 Separation function

4.2.4 BOD5

4.2.5 COD

4.2.6 Nitrogen and phosphorus

4.3 The Impact of Aeration Basin Equipment and Operation on the Performance of Secondary Clarifiers.

4.3.1 Mechanical vs. diffused-air aeration

4.3.2 Mixed liquor mixing

4.3.3 Degasification and reflocculation in aeration tanks

4.4 Features of Secondary Clarifier Construction

4.4.1 Inlet structure with a flocculation zone

4.4.2 Outlet structure

4.4.3 Scum baffles

4.5 Efficient Scum Removal from the Surface of Secondary Clarifiers

4.5.1 Conventional scum boxes

4.5.2 'Travelling' scum boxes

4.5.3 Pneumatic systems

4.6 Removal of Settled and Thickened Sludge

4.6.1 Effect on the final effluent quality

4.6.2 Mechanical scrapers

4.6.3 Vacuum sludge removal

4.7 Operation of Aeration Tank - Secondary Clarifier System for Bulking and Foaming Control

4.7.1 Use of chemicals in activated sludge process

4.7.2 Operation of secondary clarifiers

Chapter 5: Bulking and foaming control methods

5.1 Introduction

5.1.1 Microscopic characterization of the activated sludge

5.1.2 Biological foam

5.1.3 Bulking

5.1.4 The problem of excess sludge production and its disposal

5.2 Specific Control Methods

5.2.1 Bulking due to low (F/M) ratio

5.2.2 Bulking due to low dissolved oxygen concentrations

5.2.3 Bulking due to low nutrient concentration

5.2.4 Bulking due to fatty acids in the influent stream: control methods for Microthrix parvicella

5.2.5 Microbial and enzymatic preparations

5.3 Non-specific Control Methods

5.3.1 Oxidizing agents

5.3.2 Weighting or flocculating agents

5.3.3 Specific biocide

5.4 Control of Non-Filamentous Bulking ('Viscous Bulking')

5.5 Avoiding Poor Settling Properties: Alternative Separations of Activated Sludge

Chapter 6: Experiences in various countries

6.1 Introduction

6.2 Australia

6.2.1 General situation

6.2.2 What do we know of these filamentous bacteria?.

6.2.3 Bulking and foaming filamentous bacteria in Australian activated-sludge plants

6.2.4 Do filamentous bacteria populations in the same treatment plant change over time and can we control them?

6.2.5 The future

6.3 Austria

6.3.1 Intention of the investigation

6.3.2 Organization of the assessment

6.3.3 Methodology

6.3.4 Results

6.3.5 Summary and conclusion

6.4 Belgium

6.4.1 General situation

6.4.2 The M. parvicella problem

6.4.3 Polyaluminium chloride to tackle M. parvicella

6.4.4 Microthrix parvicella monitoring: a revised methodology

6.4.5 Conclusion

6.5 China

6.5.1 Introduction

6.5.2 Distribution of filamentous bacteria in activated sludge

6.5.3 Studies on sludge bulking processes and control strategy

6.6 Czech Republic

6.6.1 Separation problems - situation up to the 1980s

6.6.2 Separation problems - situation up to the mid-1990s

6.6.3 WWTPs screening - 1995-2000

6.6.4 Results of separation problems and filamentous microorganisms screening

6.6.5 Development of filamentous population in Czech activated sludge plants between 1997 and 1998

6.6.6 Screening of eight nutrient removal plants in 2000

6.6.7 Foam control strategies

6.6.8 Development in the last decade

6.7 Denmark

6.7.1 General situation

6.7.2 MiDAS: large-scale survey of the microbiology of Danish WWTPs

6.7.3 Wastewater and WWTP characteristics

6.7.4 Settling properties in Danish nutrient removal plants

6.7.5 Filamentous community composition

6.7.6 The future: surveillance and control by DNA analyses

6.8 France

6.8.1 General situation

6.8.2 Current settling and foaming problems and control measures (2012 survey)

6.8.3 A case study: metallic salt addition in an industrial size pilot-plant subject to M. parvicella bulking and foaming

6.8.4 Conclusions

6.8.5 Acknowledgments.

6.9 Greece

6.9.1 General situation

6.9.2 Reason for dysfunctions and filamentous bacteria identified

6.9.3 Solution adopted

6.9.4 A Greek case study

6.10 Italy

6.10.1 General situation

6.10.2 Characterizing the activated sludge and the qualification circuit

6.10.3 Filament surveys

6.10.4 Control methods

6.11 Malaysia

6.11.1 General situation

6.11.2 Causes of plant dysfunction

6.11.3 Implemented control strategies of filamentous sludge bulking in Malaysia

6.11.4 Future scenario of sludge bulking occurrences in Malaysia

6.12 South Africa

6.12.1 General situation

6.12.2 Overview of filamentous bulking and foaming in South African wastewater treatment works

6.12.3 Case study

6.12.4 Remedial methods to control filamentous bulking and foaming in South Africa

6.13 Spain

6.13.1 General situation

6.13.2 Separation problems and control methods applied

6.13.3 Spain case study

6.13.4 Acknowledgement

6.14 USA

6.14.1 General situations

6.14.2 Control of filaments in activated sludge systems

6.14.3 Other solid separation problems

6.14.4 Foaming

6.14.5 Viscous bulking and dispersed growth

6.14.6 Conclusions

Index.

Notes:

Includes bibliographical references at the end of each chapters and index.

Description based on online resource; title from PDF title page (ebrary, viewed October 13, 2017).

ISBN:

1-78040-864-1

OCLC:

1004999204