EFFECT OF CENTRIFUGATION ON THE REMOVAL OF EXTRACELLULAR POLYMERS AND PHYSICAL-PROPERTIES OF ACTIVATED-SLUDGE

SANIN F. D., VESILIND P.

WATER SCIENCE AND TECHNOLOGY, cilt.30, sa.8, ss.117-127, 1994 (SCI-Expanded) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 30 Sayı: 8
  • Basım Tarihi: 1994
  • Dergi Adı: WATER SCIENCE AND TECHNOLOGY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, PASCAL, Agricultural & Environmental Science Database, Analytical Abstracts, Aqualine, Aquatic Science & Fisheries Abstracts (ASFA), BIOSIS, Biotechnology Research Abstracts, CAB Abstracts, Chimica, Compendex, EMBASE, Environment Index, Geobase, MEDLINE, Pollution Abstracts, Public Affairs Index, Veterinary Science Database
  • Sayfa Sayıları: ss.117-127
  • Anahtar Kelimeler: CENTRIFUGATION, COMPACTION, EXTRACELLULAR POLYMERS, FILTERABILITY, SLUDGE, TURBIDITY, VISCOSITY, SEWAGE-SLUDGE, SURFACES, FLOCCULATION, EXTRACTION, RHEOLOGY, WATER, FLOCS
  • Orta Doğu Teknik Üniversitesi Adresli: Evet

Özet

Activated sludge is a flocculated suspension of living and dead microorganisms enmeshed together in a polymer matrix along with some organic and inorganic materials. Extracellular polymers, main components of which are the polysaccharides, proteins, and nucleic acids, act as a protective barrier to the living microbial community, and give the flee its integrity and rigidity. These polymers have been found to affect the dewatering and settling characteristics of activated sludge. Even though they were studied considerably in the past there is not a complete understanding of the relationship between the amount of polymer and changes in the physical properties of sludge. The purpose of this research is to observe the effects of centrifugal force on the extraction of the extracellular polymers from an activated sludge and to correlate the amount of polymer extracted to the subsequent physical properties of the sludge. Centrifugal forces of 2000, 5000, 8000, 11,000, 14,000, and 16,500 G were tested for their effects on the amount of extracellular polymer collected, as well as the final properties of sludge like viscosity, filterability, compactability and supernatant turbidity. Results were evaluated in comparison to those of an uncentrifuged control waste activated sludge. Removal of extracellular polymers seems to affect the viscosity of activated sludge. Filterability, as measured by the capillary suction time instrument, was affected by the extraction of polymers to a great degree. Results of the independent tests correlated well with each other and with the amount of polymers extracted. Results of this study have important implications on sludge pumping and dewatering.