CONDITIONING CHARACTERISTICS OF KAOLIN SLUDGE WITH DIFFERENT CATIONICPOLYELECTROLYTES

This study investigates the conditioning behaviors of kaolin sludge wi th different cationic polyelectrolytes. The work entails measuring the capillary suction time (CST), measuring the streaming current (SC), d etermining the moisture content of dewatered sludge cake and measuring the flee size. According to these results, The rate of dewatering (CS T measurement) does not significantly differ from polyelectrolyte mole cular weight above 6.6 x 10(6), and as well as a charge density exceed ing 15%. The amount of polyelectrolyte dosage that minimized the CST v alue is independent of the molecular weight of the four polyelectrolyt es used. In addition, the moisture content of dewatered sludge cake de pends on polyelectrolyte dosage, molecular weight and charge density. When the dosage approaches a value such that the SC becomes zero, the moisture content of dewatered kaolin sludge cake reaches the maximum o f comparable values for different polyelectrolytes. (C) 1998 Elsevier Science B.V. All rights reserved.