| Abitibi-Consolidated Company of Canada, Iroquois Falls Pulp and Paper Division operates an activated sludge treatment system. Within this process, filament bulking events often occur, causing an increase in sludge volume index where the secondary clarifier becomes inefficient. This research evaluated the variables of the process effluents that contribute to filament bulking events in relation to the sludge volume index. A statistical quantitative assessment was performed and microbiology observations were compiled for the study period from 2002 to 2005. Furthermore, operational process controls were proposed to reduce the frequency of filament bulking events. The recommendations included stabilization of process effluent variables as much as practicable, implementation of proposed operational targets, performance of routine microbiology observations, and maintenance of accurate and consistent data to predict and reduce the onset of these events. The implementation of these recommendations would in turn improve the overall environmental performance of the activated sludge treatment system. |
