Detailed Velocity and Concentration Profiles Measurement During Activated Sludge Batch Settling Using an Ultrasonic Transducer
Résumé
Activated sludge settling is a complex process requiring a thorough experimental study. It is, however, difficult to obtain information on the inner behavior of the sludge blanket without disturbing it. Optical methods are inefficient due to the opacity of sludge suspensions. This paper focuses on the investigation of activated sludge batch settling using a non-invasive method based on an ultrasonic transducer. The treatment of the signal allowed obtaining data on the settling velocity and concentration profiles inside of the suspension. The different settling regimes were clearly shown by the results on the basis of the shape of the settling velocity isolines. The precision of the gathered data is adapted to the calibration and validation of numerical models. The material used in the experimental setup can be installed in actual wastewater treatment plants.