EVALUATION OF BACTERIAL, ENTERIC VIRUS, PROTOZOAN, AND HELMINTH PERSISTENCE IN CLASS B LIME STABILIZED SLUDGE
Abstract:The use of lime to reduce or eliminate pathogen content is a cost-effective treatment method currently being employed in almost all class B biosolids production plants in New Hampshire. A bench scale model of lime stabilization has been designed and evaluated by assessing survivability of MS-2 bacteriophage and Poliovirus Type I at 28°C and 4°C; and Fecal coliforms, Salmonella and Cryptosporidium parvum at 28°C. MS-2 and Poliovirus were completely inactivated during lime stabilization, demonstrating a seven-log reduction and a five log reduction respectively at 28°C. MS-2 was completely inactivated after a two-hour incubation at pH 12 at 4°C. Poliovirus demonstrated a 1.2-log reduction following an initial liming (time point 0) at 4°C and was completely inactivated following two-hours of lime stabilization at pH 12. Fecal coliform and Salmonella bacteria were undetectable following two-hours of limestabilization at 28°C, demonstrating a seven-log reduction. C. parvum strain MD, evaluated in a limed water matrix due to low recovery efficiencies, remained infectious in neonatal mice following twenty-four hours of liming at 28°C. Currently fecal coliforms are the only microbiological indicator evaluated in Class B sludge. This research has demonstrated that C. parvum persists long after fecal coliforms have been inactivated. Further investigation is required to demonstrate inactivation of additional enteric virus such as rotavirus and hepatitis A virus along with helminth persistence such as Ascaris lumbricoides, to minimize the risks associated with land application of class B biosolids.
Document Type: Research Article
Publication date: January 1, 2003
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 These proceedings are not peer reviewed.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