scholarly journals Effects of the Sludge Retention Time and Carbon Source on Polyhydroxyalkanoate-Storing Biomass Selection under Aerobic-Feast and Anoxic-Famine Conditions

2021 ◽  
Author(s):  
Nicola Frison ◽  
Marco Andreolli ◽  
Alice Botturi ◽  
Silvia Lampis ◽  
Francesco Fatone
Keyword(s):  
Carbon Source ◽  
Retention Time ◽  
Sludge Retention Time

scholarly journals A Modified Activated Sludge Model No.3 (ASM3) for Membrane Bioreactor (MBR) with an Emphasis for Solids Hydrolysis

2018 ◽  
Vol 53 ◽  
pp. 04039
Author(s):  
Xinyue Jiang ◽  
Bin Xu
Keyword(s):  
Carbon Source ◽  
Activated Sludge ◽  
Retention Time ◽  
Membrane Bioreactor ◽  
Activated Sludge Model ◽  
Modeling Approach ◽  
Sludge Retention Time ◽  
Subsequent Effect ◽  
Hydrolysis Of ◽  
Denitrification Process

The previously assumed “inert” organics measured by respirometric method has been reported to be hydrolysable under long sludge retention time (SRT) configuration such as membrane bioreactor(MBR). The sludge production under long SRT has also shown to be lower than the standard activated sludge model (ASM) prediction. The hydrolysis of “inert” organics can provide the extra carbon source for denitrification. The current modeling approach has not yet included this aspect. In this study, a modified ASM3 was developed to account for the hydrolysis of “inert” organics and subsequent effect on the denitrification process under long SRT.

Research on Removal Effects of Pollutants by the (A/O)4 SBR Process

2013 ◽  
Vol 648 ◽  
pp. 385-388
Author(s):  
Kai Ji ◽  
Na Wei ◽  
Xiao Qing Yu ◽  
Li Ding ◽  
Jing Xiao
Keyword(s):  
Carbon Source ◽  
Removal Efficiency ◽  
Retention Time ◽  
Municipal Wastewater ◽  
Hydraulic Retention Time ◽  
Effluent Water ◽  
Phosphorous Removal ◽  
Sludge Retention Time ◽  
Temperature Ranges

The staged SBR is the process that divides aeration and sedimentation process of conventional SBR into several stages in time, and operates under the conditions of different stages of anaerobic/oxic/anoxic alternation. The experiment mainly discussed the five-stage SBR with useful volume of 12 L for nitrogen and phosphorous removal of synthetic municipal wastewater in the temperature ranges of 15~30°C. Tests revealed that under the condition of hydraulic retention time (HRT) is 8 hours and sludge retention time (SRT) is 15 day, the removal efficiency of COD, NH3-N, TN and TP can reach to 88.9%, 99.61%, 78.9% and 94.21%. The quality of effluent water is good, and don’t need to add Carbon Source through the experiment.

The Effect of PHA on Enhanced Biological Phosphorus Removal

2012 ◽  
Vol 610-613 ◽  
pp. 1343-1348
Author(s):  
Wei Han ◽  
Linjiang Yuan ◽  
Lu Chai ◽  
Kai Zhao ◽  
Guang Zhu Li
Keyword(s):  
Energy Storage ◽  
Carbon Source ◽  
Retention Time ◽  
Phosphorus Removal ◽  
Enhanced Biological Phosphorus Removal ◽  
Biological Phosphorus Removal ◽  
Sludge Retention Time ◽  
Removal Capacity ◽  
Intracellular Energy ◽  
Biological Phosphorus

Used A/O-SBR(anaerobic/aerobic alternating enhanced biological phosphorus removal system) to study carbon source and phosphate accumulating organisms (PAO) intracellular energy storage substance transformation, also studied PAO’s phosphorus removal capacity. PAO could uptake quick degradation organic matters and synthesis polyhydroxyalkanoates(PHA). PHA was a kind of intracellular energy storage substance, its content could affect PAO’s phosphorus removal capacity. When carbon source was plentiful, PAO could synthesis a lot of PHA, phosphorus removal capacity could reach 38.16 mgp/gvss. Sludge retention time could affect PAO synthesis PHA of quantity and structure. Along with the sludge retention time growth, intracellular PHA content was increased, and phosphorus uptake of desired aerobic time continues to decrease, so increasing the phosphorus removal efficiency. When the municipal sewage as carbon source, PHA was mainly composed of PHB(poly-ß-hydroxyvalerate) and PHV(poly-ß-hydroxyvalerate). Along with the sludge retention time prolongation, PAO could synthesis more PHV, PHB content was remain unchanged, PHA composition structure was changed.

Research on Developing Carbon Resource with Primary Sludge by Two-Stage Complete Mixing Ferment Process

2011 ◽  
Vol 236-238 ◽  
pp. 381-384
Author(s):  
Bai Hang Zhao ◽  
Jun Li ◽  
Jian Ren
Keyword(s):  
Carbon Source ◽  
Retention Time ◽  
Methanogenic Bacteria ◽  
Two Stage ◽  
Primary Sludge ◽  
Separation Effect ◽  
Sludge Retention Time ◽  
Carbon Resource

Two-stage complete mixing ferment process was used for developing carbon source with primary sludge. The effects of hydrolysis retention time (HRT) and sludge retention time (SRT) on the ferment system were studied. The results showed that the effective HRT was between 32 h and 36 h, and the effective SRT was between 4 d and 7 d. Under above conditions, the average effluent SCOD was in the range of 980 mg/L and 1180 mg/L, and supernatant MLSS was in the range of 50 mg/L and 80 mg/L. And then, the separation effect of the sludge thickener was clearly. Acidogenic bacteria and methanogenic bacteria could be separated effectively in the conditions.

scholarly journals Sludge retention time impacts on polyhydroxyalkanoate productivity in uncoupled storage/growth processes

2021 ◽  
pp. 149363
Author(s):  
Mariana Matos ◽  
Rafaela A.P. Cruz ◽  
Pedro Cardoso ◽  
Fernando Silva ◽  
Elisabete B. Freitas ◽  
...  
Keyword(s):  
Retention Time ◽  
Growth Processes ◽  
Sludge Retention Time

Effect of 200 days' sludge retention time on performance of a pilot scale submerged membrane bioreactor for high strength industrial wastewater treatment

2006 ◽  
Vol 53 (11) ◽  
pp. 269-276 ◽  
Author(s):  
C.T. Hay ◽  
D.D. Sun ◽  
S.L. Khor ◽  
J.O. Leckie
Keyword(s):  
Retention Time ◽  
Industrial Wastewater ◽  
Membrane Bioreactor ◽  
Hydraulic Retention Time ◽  
High Strength ◽  
Pilot Scale ◽  
Submerged Membrane Bioreactor ◽  
Sludge Retention Time ◽  
Organic Removal ◽  
Sludge Concentration

A high strength industrial wastewater was treated using a pilot scale submerged membrane bioreactor (MBR) at a sludge retention time (SRT) of 200 d. The MBR was operated at a high sludge concentration of 20 g/L and a low F/M ratio of 0.11 during 300 d of operation. It was found that the MBR could achieve COD and TOC overall removal efficiencies at more than 99 and 98% TN removal. The turbidity of the permeate was consistently in the range of 0.123 to 0.136 NTU and colour254 absorbance readings varied from 0.0912 to 0.0962 a.u. cm−1. The sludge concentration was inversely proportional to the hydraulic retention time (HRT), yielded excellent organic removal and extremely low sludge production (0.0016 kgVSS/day).

Effects of sulfate concentration and sludge retention time on the interaction between methane production and sulfate reduction for butyrate

1994 ◽  
Vol 30 (8) ◽  
pp. 45-54 ◽  
Author(s):  
O. Mizuno ◽  
Y. Y. Li ◽  
T. Noike
Keyword(s):  
Sulfate Reduction ◽  
Retention Time ◽  
Methane Production ◽  
Electron Flow ◽  
Degradation Pathway ◽  
Sulfate Concentration ◽  
High Concentration ◽  
Total Electron ◽  
Sludge Retention Time ◽  
Wide Range

The effects of sulfate concentration and COD/S ratio on the anaerobic degradation of butyrate were investigated by using 2.0 L anaerobic chemostat-type reactor at 35°C. The study was conducted over a wide range of the COD/S ratio (1.5 to 148) by varying COD concentrations (2500–10000 mg/L) and sulfate concentrations (68–1667 mg-S/L) in the substrate. The sludge retention time at each COD/S ratio was changed from 5 to 20 days. The interaction between methane producing bacteria (MPB) and sulfate-reducing bacteria (SRB) was evidently influenced by COD/S ratio in the substrate. When COD/S ratio was 6.0 or more, methane production was the predominate reaction and over 80% of the total electron flow was used by MPB. At the COD/S ratio of 1.5, SRB utilzed over 50% of the total electron flow. A large amount of sulfate reduction resulted in not only the decrease of methane production, but also the rapid increase of the bacterial growth. The degradation pathway of butyrate and the composition of bacterial populations in the reactor were also dominated by COD/S ratio. In sulfate depleted condition, butyrate was degraded to methane via acetate and hydrogen by MPB. On the other hand, butyrate was firstly degraded into sulfide and acetate in sulfate rich conditions by SRB, and the produced acetate was then degraded by acetate consuming MPB and SRB. The methanogenesis from acetate was inhibited by the high concentration of sulfide.

scholarly journals The effect of sludge retention time (SRT) on the Nitrifier typical kinetics at ambient temperature under the low ammonia density

2021 ◽  
Author(s):  
Yifan Li ◽  
Jinzhu Wu ◽  
Yongjie Liu ◽  
Feiyong Chen ◽  
Jie Guan ◽  
...  
Keyword(s):  
Growth Rate ◽  
Ambient Temperature ◽  
Retention Time ◽  
Stable State ◽  
Species Structure ◽  
Maximum Reaction Rate ◽  
Sludge Retention Time ◽  
Structure Changes ◽  
Nitrification Process ◽  
D 20

Abstract Sludge retention time (SRT) regulation is one of the essential management techniques for refined control of the main-sidestream treatment process under the low ammonia density. It is indispensable to understand the effect of SRTs changes on the Nitrifier kinetics to obtain the functional separation of the Nitrifier and the refined control of the nitrification process. In this study, Nitrifier was cultured with conditions of 35 ± 0.5 °C, pH 7.5 ± 0.2, DO 5.0 ± 0.5 mg-O/L, and SRTs was controlled for 40 d, 20 d, 10 d, and 5 d. The net growth rate (), decay rate (), specific growth rate (), the yield of the Nitrifier (), temperature parameter (), and inhibition coefficient () have been measured and extended with the SRT decreases. Instead, the half-saturation coefficient () decreased. In addition, the limited value of pH inhibition occurs (), and the pH of keeping 5% maximum reaction rate () was in a relatively stable state. The trade of kinetics may be induced by the species structure of Nitrifier changed. The Nitrosomonas proportion was increased, and the Nitrospira used to be contrary with the SRT decreasing. It is a match for the functional separation of Nitrifier when SRTs was 20 d at ambient temperature under the low ammonia density. The kinetics of ammonia-oxidizing organism (AOO) and nitrite-oxidizing organism (NOO) in Nitrifier under different SRT conditions should be measured respectively to the refined control of the partial nitrification process in the future study. HIGHLIGHT The Nitrifier typical kinetics used to be affected notably by way of SRTs changes. The species structure of the Nitrifier was recognized beneath distinctive SRTs. The change of Nitrifier kinetics with SRTs used to be estimated by the species structure changes.

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