ebsc

Useful Tool or Red Herring

Mike Foster, Principal Consultant – EBS
Paul Klopping, Principal Consultant – Callan & Brooks

Filamentous bulking is a major problem for operators of municipal and industrial activated sludge systems. For the past thirty years, renowned scientists, such as Dick Eickelboom, David Jenkins, Glenn Daigger, and Michael Richard have written extensively about the identification of the various species of filamentous bacteria and their probable causes. Because these filaments generally cannot be grown in pure cultures under laboratory conditions, most of the causative assignments regarding filamentous bacteria are empirical in nature.

Conventional wisdom says that filamentous bacterial abundance is a function of several principle causes – low dissolved oxygen, low nutrient residuals, high sludge age (low f:m), readily metabolized substrates (organic acids or starches), and sulfides. The problem arises from the fact that very few filaments can be assigned to only one cause and (as mentioned above) the causative relationships for filaments are almost entirely empirical in nature.