A comparison of physical properties of synthetic sludge with activated sludge

Conducting physical and chemical tests with activated sludge is difficult because of its constantly changing properties. To overcome this difficulty a synthetic sludge that physically and chemically resembles activated sludge was created. In this study, the physical properties of synthetic sludge were examined and compared to those of activated sludge, including particle size, filterability by specific resistance to filtration and capillary suction time, conditioning with two polyelectrolytes, flee strength, rheological properties, and residual turbidity after settling. Results of this study show striking similarities between activated sludge and synthetic sludge. Filterabilities of both sludges are almost identical. A medium-molecular-weight, medium-charge-density, cationic polymer is effective in conditioning both sludges at approximately the same dose. Activated sludge is found to have stronger flocs than synthetic sludge. However, both sludges seem to have flocs stronger than some loose and weak flocs reported in the literature. Rheological behavior in terms of apparent viscosity of the two sludges is similar. The average particle size of activated sludge is found to be slightly larger than that of synthetic sludge. Also, synthetic sludge has a higher residual turbidity than activated sludge. These differences are explained by the fact that the synthetic sludge is lacking filamentous microorganisms that form the backbone of a flee structure in activated sludge. Even though there are some differences in properties, because its overall behavior is close to that of activated sludge, synthetic sludge can be used as a surrogate material for activated sludge when reproducibility in testing is necessary.


SOYUPAK, S; KILIC, B; MUKHALLALATI, L; YURTERI, C (Informa UK Limited, 1993-01-01)
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Performance of single- and two-stage pH-stat completely stirred tank reactor (CSTR) systems for anaerobic acrylic acid biotransformation was investigated and compared. In the experiments, acetate was added with acrylic acid. Acetate concentration in both single- and two-stage reactors was continuously maintained at a nonlimiting concentration of 2000 +/- 200 mg/L. using a computer-controlled pH-stat system to allow observation of the effect of acrylate biotransformation on the more sensitive methanogenic st...
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Alkaya, Emrah; Demirer, Göksel Niyazi (Wiley, 2011-03-01)
The aim of this study was to compare a batch-fed continuously mixed anaerobic reactor (FCMR) with an anaerobic sequencing batch reactor (ASBR), in terms of waste stabilization and methane production treating sugar-beet processing wastewater and beet-pulp simultaneously. A reactor was operated as FCMR, which then was operated as an ASBR by changing operational conditions after the steady-state was reached. Although the hydraulic retention time value of the ASBR configuration was lower (8 days) than that of t...
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Erol, Funda; Oezbelge, Tuelay A.; Oezbelge, H. Oender (Informa UK Limited, 2009-01-01)
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Citation Formats
F. D. Sanin, “A comparison of physical properties of synthetic sludge with activated sludge,” WATER ENVIRONMENT RESEARCH, pp. 191–196, 1999, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/40990.