Settling behaviour of polymer flocculated water-treatment sludge I: analyses of settling curves

Settling behaviour of polymer flocculated water-treatment sludge II: effects of floc structure and floc packing

On the basis of experiments carried out using an image analysis system and static zone settlement, the alum sludge floc structure and the floc packing status with varied polymer dosages were examined in greater detail to reveal the link with the settling behaviour manifested in the “CML30 method”. The results of image analysis lead to the findings of the floc size with a pattern in initially gr...

Effect of Different Parameters on Settling Properties of Activated Sludge

Clay settling in fresh and salt water

To gain insight into the process of sedimentation occurring when clay-laden estuaries and deltas entermarinewater, we perform laboratory experiments tomeasure the settling rate of initially unflocculated kaolin clay in fresh and salt water. In fresh water, sedimentation is a slow process with the clay particle concentration gradually decreasing nearly uniformly over hours, consistent with the t...

Numerical methods for the simulation of the settling of flocculated suspensions

For one space dimension, the phenomenological theory of sedimentation of flocculated suspensions yields a model that consists of an initial-boundary value problem for a second order partial differential equation of mixed hyperbolic–parabolic type. Due to the mixed hyperbolic-parabolic nature of the model, its solutions may be discontinuous and difficulties arise if one tries to construct these ...

Monitoring of activated sludge settling ability through image analysis: validation on full-scale wastewater treatment plants.

In recent years, a great deal of attention has been focused on the research of activated sludge processes, where the solid-liquid separation phase is frequently considered of critical importance, due to the different problems that severely affect the compaction and the settling of the sludge. Bearing that in mind, in this work, image analysis routines were developed in Matlab environment, allow...