Nitrification and Denitrification in the Activated Sludge Process

by Michael H. Gerardi

Overview

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:

• Organotrophs
• The Wastewater Nitrogen Cycle
• Nitrite Ion Accumulation
• Dissolved Oxygen
• Denitrifying Bacteria
• Gaseous End Products
• Free Molecular Oxygen
• The Occurrence of Denitrification

Product Details

ISBN-13:	9780471065081
Publisher:	Wiley
Publication date:	01/09/2002
Series:	Wastewater Microbiology
Pages:	208
Product dimensions:	6.97(w) x 10.04(h) x 0.40(d)

About the Author

MICHAEL H. GERARDI is Research Project Associate and Instructor at the Pennsylvania State University in Linden, Pennsylvania.

Table of Contents

Preface.

PART I: OVERVIEW.

1 Nitrogen: Environmental and Wastewater Concerns.

2 The Oxidation States of Nitrogen.

3 Nitrogenous Compounds.

4 Bacteria.

5 The Activated Sludge Process.

PART II: NITRIFICATION.

6 Introduction to Nitrification.

7 Nitrifying Bacteria.

8 Organotrophs.

9 The Wastewater Nitrogen Cycle.

10 Nitrogen Assimilation.

11 Forms of Nitrification.

12 Indicators of Nitrification.

13 Nitrite Ion Accumulation.

14 BOD.

15 Dissolved Oxygen.

16 Alkalinity and pH.

17 Temperature.

18 Inhibition and Toxicity.

19 Mode of Operation.

20 Classification of Nitrification Systems.

21 Troubleshooting Key and Tables.

PART III: DENITRIFICATION.

22 Introduction to Denitrification.

23 Denitrifying Bacteria.

24 Biochemical Pathway and Respiration.

25 Gaseous End Products.

26 Sources of Nitrite Ions and Nitrate Ions.

27 Operational Factors Influencing Denitrification.

28 Substrate or cBOD.

29 Free Molecular Oxygen.

30 The Occurrence of Denitrification.

31 Monitoring and Correcting Accidental Denitrification.

32 Zoning.

33 Benefits of Denitrification.

APPENDIX I: THE GRAM STAIN.

APPENDIX II: F/M, HRT, MCRT.

References.

Abbreviations and Acronyms.

Chemical Compounds and Elements.

Glossary.

Index.