Applications Bulking Sludge & Foam

The creation of bulking sludge and foams due to mass development of filamentous microorganisms is a widespread problem in wastewater treatment plants. Foaming frequently also occurs in the digester as an independent phenomenon. Continuous sonication of a rather small partial flow of the return sludge by means of ultrasound causes permanent stress on the active biomass in the activated sludge tank. We have demonstrated that predominantly filamentous bacteria are damaged by this permanent “ultrasound” stress. As a consequence, the filamentous microorganisms are eliminated easily and reliably.

Bulking sludge and foam

Seasonal bulking sludge problems often occur in wastewater treatment plants. These are usually caused by filamentous organisms. Foaming in digester tanks is also a familiar occurrence and can cause substantial operational problems. Sonication of a small quantity of the return activated sludge or returned excess sludge exposes this bacterial biomass to permanent stress through cavitation and fluctuating pressure in the liquid medium. ULTRAWAVES has proven that this process causes filamentous microorganisms to particularly suffer and therefore forces them to be permanently eliminated. Use of high-power ultrasound can therefore prevent the formation of bulking sludge and stable wastewater treatment plant operation is maintained again.

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