Skip to main content

Designing Anaerobic Digestion for Energy Recovery and Pathogen Inactivation

Buy Article:

$17.50 plus tax (Refund Policy)

Or sign up for a free trial


A combined analysis of inactivation potency, operational costs and energy generation is necessary to evaluate current and alterative designs for anaerobic sewage sludge digesters. Firstorder inactivation rate constants have been determined for Escherichia coli, Eneterococcus faecalis and bacteriophage MS-2 at temperatures of 25, 37, 50, 55 and 60°C in simulated anaerobic sludge digester conditions. Inactivation rates were found to increase dramatically with a jump in digester temperature from 55 to 60°C in E. coli and E. faecalis and less dramatically in MS-2. Net energy production was modeled for four digester configurations of interest, including mesophilic treatment at 37°C, thermophilic treatment at 55°C, temperature-phased treatment combining 55 and 37°C and finally, mesophilic treatment at 37°C paired with 60°C pretreatment. The net energy production per volume of treated sludge for mesophilic treatment, temperature-phased treatment and 60°C pretreatment configurations was positive and virtually the same, with a standard deviation of about 1%. Thermophilic treatment produced about 15 % less net energy per volume of treated sludge. Pathogen inactivation performance was estimated for E. coli, E. faecalis and bacteriophage MS-2 for each treatment configuration using the batchderived inactivation rate constants. The 60°C pretreatment configuration displayed dramatically greater inactivation potency, 14+ log at 60°C versus 1-5 log in other cases. These results demonstrate that incorporating a 60°C pretreatment phase can increase pathogen inactivation performance without decreasing energy capture from digestion.

Keywords: biogas; biosolids; mesophilic; methane; pasteurization; thermophilic

Document Type: Research Article


Publication date: 2010-01-01

More about this publication?
  • Proceedings of the Water Environment Federation is an archive of papers published in the proceedings of the annual Water Environment Federation® Technical Exhibition and Conference (WEFTEC® ) and specialty conferences held since the year 2000. These proceedings are not peer reviewed.

    WEF Members: Sign in (right panel) with your IngentaConnect user name and password to receive complimentary access.
  • Subscribe to this Title
  • Membership Information
  • About WEF Proceedings
  • WEFTEC Conference Information
  • Ingenta Connect is not responsible for the content or availability of external websites
  • Access Key
  • Free content
  • Partial Free content
  • New content
  • Open access content
  • Partial Open access content
  • Subscribed content
  • Partial Subscribed content
  • Free trial content
Cookie Policy
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more