Acetate uptake efficiency of polyphosphate-accumulating organisms under exposure to surfactants

We investigated the influence of surfactants such as linear alkylbenzene sulfonates (LAS) and alcohol ethoxylates (AE) on acetate uptake by polyphosphate-accumulating organisms (PAOs) under anaerobic conditions, using the phosphate requirement for acetate uptake (+ΔP/−ΔAc ratio). In order to estimate the +ΔP/−ΔAc ratio, anaerobic batch tests were conducted using activated sludge collected from an anaerobic/oxic sequencing batch reactor used to treat municipal wastewater continuously supplemented with a detergent containing LAS and AE. We demonstrated that LAS and AE have both positive and negative impacts on acetate uptake by PAOs. The disadvantage is that long-term exposure to the detergent inhibits acetate uptake by PAOs, thus deteriorating the efficiency, even if the surfactants are no longer present during the tests. Furthermore, the existence of LAS and/or AE with acetate further diminishes the efficiency. The advantage is that LAS and AE are potential sources of polyhydroxyalkanoate for PAOs, because acetate is produced from the surfactants under anaerobic conditions.

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Anaerobic treatment of sludge: focusing on reduction of las concentration in sludge

Water Science & Technology ◽

10.2166/wst.2002.0318 ◽

2002 ◽

Vol 46 (10) ◽

pp. 159-165 ◽

Cited By ~ 20

Author(s):

F. Haggensen ◽

A.S. Mogensen ◽

I. Angelidaki ◽

B.K. Ahring

Keyword(s):

Organic Matter ◽

Anaerobic Treatment ◽

Clear Correlation ◽

Biological Degradation ◽

Anaerobic Conditions ◽

Linear Alkylbenzene ◽

Stirred Tank Reactors ◽

Bioavailable Fraction ◽

Solids Concentration ◽

Linear Alkylbenzene Sulfonates

Anaerobic degradation of linear alkylbenzene sulfonates (LAS) was tested in continuous stirred tank reactors (CSTR). LAS12 was used as a model compound and was spiked on sewage sludge. The experiments clearly showed that transformation of LAS12 occurred under anaerobic conditions. The degree of transformation varied between 14% and 25%. HPLC analysis showed that disappearance of LAS12 was followed by the formation of a metabolite. The experiments indicated that there is a clear correlation between degradation of organic matter contained in sludge and transformation of LAS12. When the reduction degree of the organic matter increased from 22% to 28%, the transformation degree of LAS12 also increased, from 14% to 20%. Decreasing the total solids concentration of the influent sludge or increasing the spiked concentration of LAS12 did not alter the degree of LAS12 transformation significantly. A clear correlation between transformed and bioavailable LAS12 was found, indicating that it is merely the bioavailable fraction of LAS12 that is transformed by anaerobic digestion. The results from the present study are promising and indicate that a great potential for biological degradation of LAS is possible even at anaerobic conditions.

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Removal of alcohol ethoxylates, alkyl ethoxylate sulfates, and linear alkylbenzene sulfonates in wastewater treatment

Environmental Toxicology and Chemistry ◽

10.1002/etc.5620170909 ◽

1998 ◽

Vol 17 (9) ◽

pp. 1705-1711 ◽

Cited By ~ 68

Author(s):

Drew C. McAvoy ◽

Scott D. Dyer ◽

Nicholas J. Fendinger ◽

William S. Eckhoff ◽

David L. Lawrence ◽

...

Keyword(s):

Wastewater Treatment ◽

Alcohol Ethoxylates ◽

Linear Alkylbenzene ◽

Linear Alkylbenzene Sulfonates

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The effect of nitrite on aerobic phosphate uptake and denitrifying activity of phosphate-accumulating organisms

Water Science & Technology ◽

10.2166/wst.2006.165 ◽

2006 ◽

Vol 53 (6) ◽

pp. 21-27 ◽

Cited By ~ 18

Author(s):

Y. Yoshida ◽

K. Takahashi ◽

T. Saito ◽

K. Tanaka

Keyword(s):

Phosphorus Removal ◽

Sequencing Batch Reactor ◽

Municipal Wastewater ◽

Phosphate Uptake ◽

Batch Reactor ◽

Biological Phosphorus Removal ◽

Interesting Observation ◽

Batch Tests ◽

Uptake Activity ◽

Biological Phosphorus

An anaerobic/aerobic/anoxic/aerobic sequencing batch reactor (SBR) was operated with municipal wastewater to investigate the effect of nitrite on biological phosphorus removal (BPR). When nitrite accumulated, aerobic phosphate uptake activity significantly decreased and, in case of hard exposure to nitrite, BPR severely deteriorated. The interesting observation was that the relative anoxic activity of phosphate accumulating organisms (PAOs) increased after nitrite exposure. Moreover batch tests of aerobic phosphate uptake in the presence/absence of nitrite indicated that PAOs with the higher relative anoxic activity are less sensitive to nitrite exposure. From these results, we concluded that BPR is sensitive to nitrite exposure, but BPR containing PAOs with the higher relative anoxic activity is possibly more stable against nitrite than BPR containing PAOs with the lower relative anoxic activity.

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Bioassay for glycogen determination in biological phosphorus removal systems

Water Science & Technology ◽

10.2166/wst.1998.0715 ◽

1998 ◽

Vol 37 (4-5) ◽

pp. 541-547 ◽

Cited By ~ 4

Author(s):

Damir Brdjanovic ◽

Mark C. M. van Loosdrecht ◽

Christine M. Hooijmans ◽

Takashi Mino ◽

Guy J. Alaerts ◽

...

Keyword(s):

Phosphorus Removal ◽

Glycogen Content ◽

Batch Reactor ◽

Measurement Techniques ◽

Limiting Factor ◽

Biological Phosphorus Removal ◽

Acetate Uptake ◽

Batch Tests ◽

Biological Phosphorus

Glycogen plays an important role in biological phosphorus removal from wastewaters. Existing measurement techniques often overestimate the glycogen content of the biomass due to the presence of glucose and/or other carbohydrates than glycogen in the cell material. As an alternative to conventional methods a bioassay for glycogen determination in biological phosphorus removal systems was developed. The bioassay is based on the strict stoichiometric coupling between anaerobic acetate uptake and glycogen consumption. In other words, the glycogen concentration of the sludge was determined indirectly by measuring the maximal total acetate uptake by the activated sludge in anaerobic batch tests. The bioassay was successfully tested for the determination of glycogen content of the sludge taken from the lab-scale, acetate-fed, anaerobic-aerobic-settling sequencing batch reactor operating at pH 7±0.1 and temperature of 20°C. This determination of glycogen requires that glycogen (not poly-P) is the limiting factor for anaerobic acetate uptake. A method to verify this assumption based on the effect of pH on phosphate/acetate ratio is proposed and used. The bioassay is easy to apply and gives a direct measure of the glycogen content of bio-P bacteria, but its reliability still needs to be verified at full-scale biological P-removal plants.

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Dynamics of phosphorus and organic substrates in anaerobic and aerobic phases of a sequencing batch reactor

Water Science & Technology ◽

10.2166/wst.1994.0274 ◽

1994 ◽

Vol 30 (6) ◽

pp. 237-246 ◽

Cited By ~ 21

Author(s):

A. Carucci ◽

M. Majone ◽

R. Ramadori ◽

S. Rossetti

Keyword(s):

Sequencing Batch Reactor ◽

Municipal Wastewater ◽

Batch Reactor ◽

General Assumption ◽

Organic Substrate ◽

Operating Conditions ◽

Phosphate Removal ◽

Substrate Uptake ◽

Organic Substrates ◽

Polyphosphate Metabolism

This paper describes a lab-scale experimentation carried out to study enhanced biological phosphate removal (EBPR) in a sequencing batch reactor (SBR). The synthetic feed used was based on peptone and glucose as organic substrate to simulate the readily biodegradable fraction of a municipal wastewater (Wentzel et al., 1991). The experimental work was divided into two runs, each characterized by different operating conditions. The phosphorus removal efficiency was considerably higher in the absence of competition for organic substrate between P-accumulating and denitrifying bacteria. The activated sludge consisted mainly of peculiar microorganisms recently described by Cech and Hartman (1990) and called “G bacteria”. The results obtained seem to be inconsistent with the general assumption that the G bacteria are characterized by anaerobic substrate uptake not connected with any polyphosphate metabolism. Supplementary anaerobic batch tests utilizing glucose, peptone and acetate as organic substrates show that the role of acetate in the biochemical mechanisms promoting EBPR may not be so essential as it has been assumed till now.

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Formulating characteristics of high and low 2-phenyl linear alkylbenzene sulfonates in liquid detergents

Journal of the American Oil Chemists Society ◽

10.1007/bf02663085 ◽

1988 ◽

Vol 65 (3) ◽

pp. 398-404 ◽

Cited By ~ 6

Author(s):

Joseph C. Drozd ◽

Wilma Gorman

Keyword(s):

Linear Alkylbenzene ◽

Linear Alkylbenzene Sulfonates

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Performance of aerobic granular sludge at variable circulation rate in anaerobic–aerobic conditions

Water Science & Technology ◽

10.2166/wst.2014.156 ◽

2014 ◽

Vol 69 (11) ◽

pp. 2252-2257 ◽

Cited By ~ 3

Author(s):

Hasnida Harun ◽

Aznah Nor Anuar ◽

Zaini Ujang ◽

Noor Hasyimah Rosman ◽

Inawati Othman

Keyword(s):

Municipal Wastewater ◽

Granular Sludge ◽

Ammonia Removal ◽

Soy Sauce ◽

Volume Index ◽

Aerobic Granular Sludge ◽

Circulation Rate ◽

Anaerobic Conditions ◽

Aerobic Conditions ◽

Mixed Liquor

Aerobic granular sludge (AGS) has been applied to treat a broad range of industrial and municipal wastewater. AGS can be developed in a sequencing batch reactor (SBR) with alternating anaerobic–aerobic conditions. To provide anaerobic conditions, the mixed liquor is allowed to circulate in the reactor without air supply. The circulation flow rate of mixed liquor in anaerobic condition is the most important parameter of operation in the anaerobic-AGS processes. Therefore, this study investigates the effect of circulation rate on the performance of the SBR with AGS. Two identical reactors namely R1 and R2 were operated using fermented soy sauce wastewater at circulation rate of 14.4 and 36.0 l/h, respectively. During the anaerobic conditions, the wastewater was pumped out from the upper part of the reactor and circulated back into the bottom of the reactor for 230 min. A compact and dense AGS was observed in both reactors with a similar diameter of 2.0 mm in average, although different circulation rates were adopted. The best reactor performance was achieved in R2 with chemical oxygen demand removal rate of 89%, 90% total phosphorus removal, 79% ammonia removal, 10.1 g/l of mixed liquor suspended solids and a sludge volume index of 25 ml/g.

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