In Mexico, physicochemical sludge contains high levels of pathogens; and alkaline stabilization is an alternative for their control. However, the odours caused mainly by ammonia generation represent a disadvantage. On the other hand, the ammonia is known as an effective disinfectant. The aim of this study was to evaluate the disinfectant properties of ammonia in sludge, and use it in a closed alkaline stabilization system, which, not only copes with odours but also increases the efficiency of the process. Raw sludge from a municipal wastewater treatment plant using a physicochemical process was used. Ammonia was applied in doses from 10 to 50% w/w; also, doses from 5 to 40% of CaO were applied in open and closed systems and raw and treated sludge quality was evaluated. Results showed that ammonia removed 6 and 5 logs of faecal coliforms and Salmonella spp., respectively and up to 94% of viable helminth ova. The closed system was more efficient than the open system when applying doses from 5 to 20% of CaO. Finally, the results indicate that the ammonia represents an alternative to disinfecting wastewater sludge and it can be used to enhance alkaline stabilization processes.
Skip Nav Destination
Research Article| November 01 2002
Improved alkaline stabilization of municipal wastewater sludge
Water Sci Technol (2002) 46 (10): 139–146.
J.M. Mendez, B.E. Jiménez, J.A. Barrios; Improved alkaline stabilization of municipal wastewater sludge. Water Sci Technol 1 November 2002; 46 (10): 139–146. doi: https://doi.org/10.2166/wst.2002.0312
Download citation file: