The Microbiology Of Anaerobic Digesters

Introduction
Completely mixed anaerobic digesters are the most commonly used treatment system in North America for the degradation of municipal sludges. Although these suspended-growth systems are not used as commonly at industrial wastewater treatment plants, more and more industrial plants are using fixed-film anaerobic digesters for the treatment of soluble organic compounds in their wastewaters.

Anaerobic digesters perform most of the degradation of organic compounds at wastewater treatment plants.

However, digesters often experience operational problems that result in process upsets and increased operational costs. Examples of process upsets and operational problems include foam and scum production, decanting and dewatering difficulties, loss of treatment efficiency, toxic upsets, and “souring” of the digester.

Poorly operating anaerobic digesters often contribute to operational problems in other treatment units such as the activated sludge process, gravity thickener, clarifiers, and sludge dewatering facilities. Because of the importance of anaerobic digesters in wastewater treatment processes, a review of the microbiology of the bacteria and the operational conditions that affect their activity is of value in addressing successful and cost-effective operation.

This book provides an in-depth review of the bacteria, their activity, and the operational conditions that affect anaerobic digester performance. The identification of operational problems and troubleshooting and corrective measures for process control are presented.

This book is prepared for an audience of operators and technicians who are responsible for the daily operation of anaerobic digesters. It presents troubleshooting and process control measures to reduce operational costs, maintain treatment efficiency, and prevent system upsets.

The Microbiology of Anaerobic Digesters is the third book in the Wastewater Microbiology Series by John Wiley & Sons.

This series is designed for operators and technicians, and it presents a microbiological review of the organisms involved in wastewater treatment processes and provides biological techniques for monitoring and regulating these processes.