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

Abstract

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