Effect of EDTA on activated sludge properties

Date

2001-02-01

Author

Sanin, Faika Dilek

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Bacterial extracellular polymers have been found to be important in bioflocculation of activated sludge. In this study ethylene diamine tetra acetic acid (EDTA) method of extracting bacterial extracellular polymers is examined. Following extractions, it is observed that EDTA extracted significant amounts of biopolymers. However, the chemical treatment causes serious changes in sludge properties. Sludge particle size is reduced from 21 mum to 14.6 mum, filtration properties of sludge deteriorates, indicated by an increase of capillary suction time (CST) from 48.1 sec to 232 sec and the viscosity of sludge increases from 5.5 cP to 7.1 cP. The effects are so dramatic, that it is concluded that beyond extracting biopolymers, this technique damages the microbial cell walls and solubilizes some cells.

Subject Keywords

Activated sludge, Extracellular polymers, EDTA, Centrifugation, Blending, Physical properties of sludge

URI

https://hdl.handle.net/11511/52678

Journal

FRESENIUS ENVIRONMENTAL BULLETIN

Collections

Department of Environmental Engineering, Article

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Citation Formats

F. D. Sanin, “Effect of EDTA on activated sludge properties,” FRESENIUS ENVIRONMENTAL BULLETIN, pp. 165–169, 2001, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/52678.