Nitrification and Denitrification in the Activated Sludge Process

✍ Scribed by Michael H. Gerardi

• Publisher: Wiley-Interscience
• Year: 2002
• Tongue: English
• Leaves: 208
• Series: Wastewater microbiology
• Edition: 3
• Category: Library

✦ Synopsis

Nitrification and Denitrification in the Activated Sludge Process, the first in a series on the microbiology of wastewater treatment, comprises the critical topics of cost-effective operation, permit compliance, process control, and troubleshooting in wastewater treatment plants. Avoiding the technical jargon, chemical equations, and kinetics that typically accompany such texts, Nitrification and Denitrification in the Activated Sludge Process directly addresses plant operators and technicians, providing necessary information for understanding the microbiology and biological conditions that occur in the treatment process.Of special interest to wastewater treatment plant operators are the bacteria that degrade nitrogenous wastes–the nitrifying bacteria–and the bacteria that degrade carbonaceous wastes–the cBOD-removing bacteria. Both groups of bacteria need to be routinely monitored and operational conditions favorably adjusted to ensure desired nitrification. Each chapter in this groundbreaking study offers a better understanding of the importance of nitrification and denitrification and the bacteria involved in these crucial processes. Chapters include:OrganotrophsThe Wastewater Nitrogen CycleNitrite Ion AccumulationDissolved OxygenDenitrifying BacteriaGaseous End ProductsFree Molecular OxygenThe Occurrence of Denitrification

✦ Table of Contents

Nitrification and Denitrification in the Activated Sludge Process......Page 4
Contents......Page 10
Preface......Page 14
PART I OVERVIEW......Page 16
1 Nitrogen: Environmental and Wastewater Concerns......Page 18
2 The Oxidation States of Nitrogen......Page 26
3 Nitrogenous Compounds......Page 32
4 Bacteria......Page 36
5 The Activated Sludge Process......Page 46
PART II NITRIFICATION......Page 50
6 Introduction to Nitrification......Page 52
7 Nitrifying Bacteria......Page 58
8 Organotrophs......Page 70
9 The Wastewater Nitrogen Cycle......Page 78
10 Nitrogen Assimilation......Page 92
11 Forms of Nitrification......Page 96
12 Indicators of Nitrification......Page 102
13 Nitrite Ion Accumulation......Page 106
14 BOD......Page 110
15 Dissolved Oxygen......Page 118
16 Alkalinity and pH......Page 124
17 Temperature......Page 130
18 Inhibition and Toxicity......Page 134
19 Mode of Operation......Page 138
20 Classification of Nitrification Systems......Page 142
21 Troubleshooting Key and Tables......Page 144
PART III DENITRIFICATION......Page 148
22 Introduction to Denitrification......Page 150
23 Denitrifying Bacteria......Page 152
24 Biochemical Pathway and Respiration......Page 154
25 Gaseous End Products......Page 158
26 Sources of Nitrite Ions and Nitrate Ions......Page 160
27 Operational Factors Influencing Denitrification......Page 162
28 Substrate or cBOD......Page 164
29 Free Molecular Oxygen......Page 166
30 The Occurrence of Denitrification......Page 168
31 Monitoring and Correcting Accidental Denitrification......Page 174
32 Zoning......Page 178
33 Benefits of Denitrification......Page 182
APPENDIX I THE GRAM STAIN......Page 184
APPENDIX II F/M, HRT, MCRT......Page 186
References......Page 190
Abbreviations and Acronyms......Page 194
Chemical Compounds and Elements......Page 196
Glossary......Page 198
Index......Page 206