The influence of key chemical constituents in activated sludge on surface and flocculating properties

Wilén, Britt‐Marie; Jin, Bo; Lant, Paul

doi:10.1016/s0043-1354(02)00629-2

Cited by 518 publications

(195 citation statements)

References 42 publications

Supporting

Mentioning

174

Contrasting

Unclassified

Order By: Relevance

“…The explanations for this phenomenon are (i) Complexing of Cd(II) ions with some cell surfactant protein changed surface charges of cells and membrane potential, thereby converted hydrophilic groups into hydrophobic groups on the cell surface and enhanced hydrophobicity of strains [28]; (ii) The production of extracellular polymeric substances (EPS) were restrained with addition of low concentration of Cd(II) ions. And it was confirmed that the total content of EPS showed a negative effect on the relative hydrophobicity [29]; (iii) It was found that biosurfactant was produced by P. aeruginosa [30], and addition of low concentration of Cd(II) ions increased production of biosurfactants, which promoted the transfer of hydrophobic substrate. The impact of high concentration of Cd(II) ions on hydrophobicity of P. aeruginosa during degradation of BDE-209 was ignorable, compared with what it had on degradation rate.…”

Section: Effect Of Cd(ii) Ions On Csh Of P Aeruginosamentioning

confidence: 82%

Effect of cadmium ion on biodegradation of decabromodiphenyl ether (BDE-209) by Pseudomonas aeruginosa

Shi

Yin

et al. 2013

Journal of Hazardous Materials

View full text Add to dashboard Cite

Section: Effect Of Cd(ii) Ions On Csh Of P Aeruginosamentioning

confidence: 82%

Effect of cadmium ion on biodegradation of decabromodiphenyl ether (BDE-209) by Pseudomonas aeruginosa

Shi

Yin

et al. 2013

Journal of Hazardous Materials

View full text Add to dashboard Cite

“…EPS, an important composition of activated sludge Nielsen et al, 1996), plays an important role in biological wastewater treatment (Wilen et al, 2003;Neyens et al, 2004;Wang et al, 2005;Long et al, 2009). Because there are other components in activated sludge, EPS must first be extracted before being studied.…”

Section: Introductionmentioning

confidence: 99%

Evaluation of the damage of cell wall and cell membrane for various extracellular polymeric substance extractions of activated sludge

Guo

Liu

Xiao

2014

Journal of Biotechnology

View full text Add to dashboard Cite

a b s t r a c t Extracellular polymeric substances (EPS) are susceptible to contamination by intracellular substances released during the extraction of EPS owing to the damage caused to microbial cell structures. The damage to cell walls and cell membranes in nine EPS extraction processes of activated sludge was evaluated in this study. The extraction of EPS (including proteins, carbohydrates and DNA) was the highest using the NaOH extraction method and the lowest using formaldehyde extraction. All nine EPS extraction methods in this study resulted in cell wall and membrane damage. The damage to cell walls, evaluated by 2-keto-3-deoxyoctonate (KDO) and N-acetylglucosamine content changes in extracted EPS, was the most significant in the NaOH extraction process. Formaldehyde extraction showed a similar extent of damage to cell walls to those detected in the control method (centrifugation), while those in the formaldehydeNaOH and cation exchange resin extractions were slightly higher than those detected in the control. N-acetylglucosamine was more suitable than KDO for the evaluation of cell wall damage in the EPS extraction of activated sludge. The damage to cell membranes was characterized by two fluorochromes (propidium iodide and FITC Annexin V) with flow cytometry (FCM) measurement. The highest proportion of membrane-damaged cells was detected in NaOH extraction (26.54% of total cells) while membranedamaged cells comprised 8.19% of total cells in the control.

show abstract

“…At the stationary phase or long SRT, cells produced less EPS than that at the exponential phase or short SRT. The surface would become more hydrophobic as the EPS decrease, because the content of EPS had a negative effect on the relative hydrophobicity (Wilen et al 2003).…”

Section: Resultsmentioning

confidence: 99%

Characteristics of free cells and aggregated flocs for the flocculation and sedimentation of activated sludge

2015

Int. J. Environ. Sci. Technol.

View full text Add to dashboard Cite

Laboratory experiments were conducted to investigate the correlation of the free cells/aggregated flocs characteristics and the sludge flocculation and separation behavior during the activated sludge process. Activated sludge was cultured in three laboratory-scale batch reactors with same carbon sources of glucose but different sludge retention times (SRTs) of 5, 10 and 20 days. The variation in the operation condition produced sludge with different flocculation and separation characteristics. The reactor performance in terms of bioflocculation as measured by the amount of suspended solids in the effluent, sludge sedimentation and compression as measured by the sludge value index improved considerably as the SRT lengthened. The higher SRT was related to less negatively charged surface of free cells and more hydrophobic of aggregated flocs. The negative zeta potential of aggregated flocs (11-13 mV) was smaller than that of free cells (15-23 mV), and free cells carrying lesser negative surface charges resulted in effluent clarification. Hydrophobicity of aggregated flocs (10-17 %) in each reactor was higher than that of free cells (5-8 %). The increase in hydrophobicity of aggregated flocs had positive effect on settleability. Floc strength measured by breakage/erosion index was closely related to hydrophobicity of aggregated flocs, but no correlation could be established with zeta potential of aggregated flocs. In addition, different bacterial species existed in free cells and aggregated flocs. Microbial similarity between free cells and aggregated flocs increased with shorter SRT and was closely related to effluent clarification.

show abstract

The influence of key chemical constituents in activated sludge on surface and flocculating properties

Cited by 518 publications

References 42 publications

Effect of cadmium ion on biodegradation of decabromodiphenyl ether (BDE-209) by Pseudomonas aeruginosa

Effect of cadmium ion on biodegradation of decabromodiphenyl ether (BDE-209) by Pseudomonas aeruginosa

Evaluation of the damage of cell wall and cell membrane for various extracellular polymeric substance extractions of activated sludge

Characteristics of free cells and aggregated flocs for the flocculation and sedimentation of activated sludge

Contact Info

Product

Resources

About