1. Sludge dewatering with cyclodextrins.
- Author
-
Hartong BH, Abu-Daabes M, Le T, Saidan M, and Banerjee S
- Subjects
- Biomechanical Phenomena, Hydrophobic and Hydrophilic Interactions, Industrial Waste, Paper, Polymers chemistry, Surface Tension drug effects, Wood, Cyclodextrins chemistry, Sewage chemistry, Waste Management methods
- Abstract
Cyclodextrins (CDs) increase the cake solids and drainage rate of belt-pressed biological or primary sludge when added to the sludge slurry along with conventional conditioning chemicals. These benefits are obtained at very low CD dosage. A 2.8 percentage point increase in cake solids was obtained in a full-scale trial with mixed primary and biological sludge from a paper mill. CDs also decrease the specific resistance to filtration and increase the capture rate of solids during belt pressing. Mechanistic studies showed that CDs increase the surface tension of c-PAM polymers in water and reduce the turbidity, indicating that they are able to aggregate the charged polymers, and, by inference, sludge particles treated with the polymer. A mechanism is proposed where CDs reduce excessively charged regions of the polymer-treated surface of the sludge, thereby facilitating its flocculation.
- Published
- 2007
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