Determination of the optimal dose of polyelectrolyte sludge conditioner considering particle sedimentation effects

The specific resistance to filtration (SRF) of sludge was determined using both a leaf filter and a Buncher funnel. The filterability of a kaolin susp ension and an alum sludge were characterized using SRF data and capillary s uction time (CST) measurements. Filter orientation during the leaf filter t est and stirring during the Buncher funnel test affected the SRF values, an d the optimal dosage of polyelectrolyte conditioner (defined as the dosage that yields the minimum resistance to filtration) varied depending on the t ype of test used. Therefore, the optimal dose of polyelectrolyte was an ope rationally defined value that depended on the geometry of the filter chambe r and fluid/particle interactions, such as sedimentation. (C) 2000 Elsevier Science Ltd. All rights reserved.