Physicochemical properties and stability of activated sludge flocs under temperature upshifts from 30 to 45 °C

Abstract The computerized image analysis system has been successfully used for determination and statistical processing of the following geometric characteristics of activated sludge flocs: longest dimension, breadth, equivalent diameter, cross-sectional area, perimeter, elongation, and circularity. These parameters could be effectively and precisely determined by the system applied. In addition, the studied method, as compared to direct microscope observation and photography floc-sizing methods, was found to be more accurate, less time-consuming, and less dependent on the investigators.

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Deep learning-based morphology classification of activated sludge flocs in wastewater treatment plants

Environmental Science Water Research & Technology ◽

10.1039/d0ew00908c ◽

2021 ◽

Author(s):

Hisashi Satoh ◽

Yukari Kashimoto ◽

Naoki Takahashi ◽

Takashi Tsujimura

Keyword(s):

Wastewater Treatment ◽

Deep Learning ◽

Activated Sludge ◽

Morphological Change ◽

Wastewater Treatment Plants ◽

Filamentous Bacteria ◽

Sludge Flocs

A deep learning-based two-label classifier 1 recognized a 20% morphological change in the activated flocs. Classifier-2 quantitatively recognized an abundance of filamentous bacteria in activated flocs.

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Characterization of Extracellular Polymeric Substances in Rotating Biological Contactors and Activated Sludge Flocs

Environmental Technology ◽

10.1080/09593332208618231 ◽

2001 ◽

Vol 22 (8) ◽

pp. 951-959 ◽

Cited By ~ 18

Author(s):

M. Martín-Cereceda ◽

F. Jorand ◽

A. Guinea ◽

J. C. Block

Keyword(s):

Activated Sludge ◽

Extracellular Polymeric Substances ◽

Sludge Flocs ◽

Rotating Biological Contactors

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Study of factors affecting simultaneous nitrification and denitrification (SND)

Water Science & Technology ◽

10.2166/wst.1999.0262 ◽

1999 ◽

Vol 39 (6) ◽

pp. 61-68 ◽

Cited By ~ 118

Author(s):

Klangduen Pochana ◽

Jürg Keller

Keyword(s):

Carbon Source ◽

Activated Sludge ◽

Physical Phenomenon ◽

Treatment Plant ◽

Batch Reactors ◽

Sequencing Batch Reactors ◽

Factors Affecting ◽

Floc Size ◽

Sludge Flocs ◽

Activated Sludge Systems

Experiments have been performed to gain an understanding of the conditions and processes governing the occurrence of SND in activated sludge systems. Sequencing batch reactors (SBRs) have been operated under controlled conditions using the wastewater from the first anaerobic pond in an abattoir wastewater treatment plant. Under specific circumstances, up to 95% of total nitrogen removal through SND has been found in the system. Carbon source and oxygen concentrations were found to be important process parameters. The addition of acetate as an external carbon source resulted in a significant increase of SND activity in the system. Stepwise change of DO concentration has also been observed in this study. Experiments to determine the effect of the floc size on SND have been performed in order to test the hypothesis that SND is a physical phenomenon, governed by the diffusion of oxygen into the activated sludge flocs. Initial results support this hypothesis but further experimental confirmation is still required.

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Effects of potassium ion on sludge settling, dewatering and effluent properties

Water Science & Technology ◽

10.2166/wst.1998.0655 ◽

1998 ◽

Vol 37 (4-5) ◽

pp. 317-324 ◽

Cited By ~ 23

Author(s):

Sudhir N. Murthy ◽

John T. Novak

Keyword(s):

Activated Sludge ◽

Field Studies ◽

Potassium Ion ◽

Potassium Ions ◽

Nutrient Requirements ◽

Sludge Dewatering ◽

Capillary Suction ◽

Sludge Flocs ◽

Sludge Properties ◽

Sludge Settling

Potassium ions appear to play an important role in determining the nature of activated sludge flocs. Relative to sodium, the concentration of potassium ions in most industrial activated sludge is typically low. Laboratory and field studies were conducted to examine the influence of potassium on activated sludge properties. The concentration of potassium affected the concentration of readily extractable (slime) proteins in the floc and the proteins in the surrounding solution. In laboratory tests, an increase in this cation's concentration beyond nutrient requirements impeded sludge dewatering properties as measured by capillary suction time (CST) and specific resistance to filtration (SRF) and associated with an increase in soluble protein. An increase in effluent total organic carbon and effluent turbidity was observed at higher concentrations of this ion. Conversely, an increase in concentration of potassium ion improved the settling properties of sludge with low equivalent monovalent to divalent cation ratio.

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Efficiency of Biological Phosphorus Removal by Filamentous Bacteria

Chemistry-Didactics-Ecology-Metrology ◽

10.1515/cdem-2016-0010 ◽

2016 ◽

Vol 21 (1-2) ◽

pp. 117-123 ◽

Cited By ~ 1

Author(s):

Alicja Machnicka ◽

Klaudiusz Grübel

Keyword(s):

Activated Sludge ◽

Phosphorus Removal ◽

Water Environment ◽

Treatment Plant ◽

Chemical Precipitation ◽

Heterogeneous Structure ◽

Filamentous Bacteria ◽

Biological Phosphorus Removal ◽

High Concentration ◽

Sludge Flocs

AbstractPhosphorus removal in wastewater treatment plant is carried out by chemical precipitation, advanced biological treatment or a combination of both. One of the biggest problems with high concentration of phosphorus in water environment is eutrophication. Activated sludge flocs have a heterogeneous structure, which consist of a variety of microorganisms. Filamentous bacteria are normally present in the activated sludge and have ability to assimilation of phosphorus. In this study phosphorus accumulation by isolated filamentous bacteria from activated sludge foam was present.

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