Removal and fate of estrogens in an anaerobic-anoxic-oxic activated sludge system

2011 ◽  
Vol 63 (1) ◽  
pp. 51-56 ◽  
Author(s):  
Y. M. Li ◽  
Q. L. Zeng ◽  
S. J. Yang
Keyword(s):  
Activated Sludge ◽  
Removal Efficiency ◽  
Laboratory Scale ◽  
Dominant Mechanism ◽  
Waste Sludge ◽  
Activated Sludge System ◽  
17Β Estradiol ◽  
Solid Phases ◽  
Final Effluent

Laboratory-scale experiments were conducted to investigate the removal and fate of estrogens 17β-estradiol (E2) and 17α-ethinylestradiol (EE2) in an anaerobic-anoxic-oxic (AAO) activated sludge system. Estrogen concentrations in the aqueous and solid phases in each reactor of AAO system were analyzed separately. E2 was not detected in the final effluent. The anaerobic, anoxic and oxic reactors accounted for 71%, 7% and 22% of the overall E2 removal, respectively. The overall EE2 removal efficiency was about 80%, and the anaerobic, anoxic and oxic reactors were responsible for 44%, 8% and 48% of the overall EE2 removal, respectively. In anaerobic unit, sorption was the dominant mechanism for the removal of E2 and EE2. While E2 was degraded in all the three units of the AAO system, EE2 was only degraded in the anoxic and aerobic units. Biodegradation is important for the fate of E2 compared to sorption. Of the total influent E2 in the AAO system, 99.99% was biodegraded and 0.01% remained in the waste sludge. Nevertheless, both sorption and biodegradation play important roles in the removal of EE2. Of the total influent EE2, 79.1% was degraded by activated sludge, 19.9% was discharged in the effluent and 1% remained in the waste sludge.

Start-Up of A2/O Humic Activated Sludge Systemphosphorus Removal Efficiency Analysis

2010 ◽  
Vol 113-116 ◽  
pp. 2201-2207 ◽  
Author(s):  
Jun Yin ◽  
Lei Wu ◽  
Ke Zhao ◽  
Yu Juan Yu
Keyword(s):  
Activated Sludge ◽  
Removal Efficiency ◽  
Phosphorus Removal ◽  
Removal Rate ◽  
Phosphorus Uptake ◽  
Phosphorus Release ◽  
Activated Sludge System ◽  
Start Up ◽  
Article Analysis ◽  
Sludge Activity

In this article, analysis the start-up of A2/O humic activated sludge system phosphorus removal efficiency and the characteristics of anaerobic phosphorus release, aerobic phosphorus uptake, sludge activity and their change in the Series Technologies process. The results show that A2/O humic activated sludge system phosphorus removal rate stabilized at 90.7% ~ 97.6%. Sludge activity except for anoxic zone 2 increased, along the process showed a gradual decrease trend.

Evaluation of ozonation and cryptic growth for biosolids management in wastewater treatment

1999 ◽  
Vol 39 (10-11) ◽  
pp. 155-158 ◽  
Author(s):  
E. Egemen ◽  
J. Corpening ◽  
J. Padilla ◽  
R. Brennan ◽  
N. Nirmalakhandan
Keyword(s):  
Activated Sludge ◽  
Continuous Flow ◽  
Growth Conditions ◽  
Aeration Tank ◽  
Biomass Growth ◽  
Waste Sludge ◽  
Process Configuration ◽  
Activated Sludge System ◽  
Expensive Problems ◽  
Cryptic Growth

The ultimate disposal of biosolids has been and continues to be one of the most expensive problems faced by wastewater utilities. The objective of this research is to develop a process configuration for reducing the waste sludge generation in an activated sludge plant by promoting cryptic growth conditions (i.e., biomass growth on intracellular products). For this purpose, excess biosolids from a continuous flow activated sludge system were solubilized using ozone as the cell lysis agent, and then returned to the aeration tank. It is hypothesized that growth under such cryptic conditions will result in low net microbial yields, and hence, minimal net solids wastage. The results of these preliminary studies indicate that the proposed process configuration has the potential to reduce the waste sludge production by 40% to 60%.

Study on pH Shock Resistance of the Magnetic Micro-Aerobic Activated Sludge System

2013 ◽  
Vol 807-809 ◽  
pp. 1441-1444
Author(s):  
Hui Xia Lan ◽  
Rui Chen ◽  
Ping Ma ◽  
Heng Zhang ◽  
Shan Hong Lan
Keyword(s):  
Activated Sludge ◽  
Removal Efficiency ◽  
Magnetic Powder ◽  
Effect Of Ph ◽  
Activated Sludge System ◽  
Low Load ◽  
Ph Shock ◽  
Shock Resistance ◽  
Recovery Experiment

the effect of pH shock on the magnetic micro-aerobic activated sludge system used to deal with low load glucose wastewater was studied. After pH shocking under the condition of pH=6.0 and 9.0 for 15 days, CODCr removal efficiency of the reactor with magnetic powder was higher than that of the reactor without magnetic powder, and remained above 80% in the 5 days recovery experiment at pH=7.5, while about 50% of the reactor without magnetic powder. SVI in the reactor with magnetic powder was lower than that of the reactor without magnetic powder after pH shocking, and after the 5 days' recovery experiments, SVI of the sludge with magnetic powder could recovered to the original value, but the indicators of the sludge without magnetic powder could not recovered to the original value.

Effects of Cr3+ on COD Changes of SBR Activated Sludge System with Different Chromium Loads and Different Initial SVIs

2013 ◽  
Vol 448-453 ◽  
pp. 438-443
Author(s):  
Guo Ri Dong ◽  
Jian She Liu
Keyword(s):  
Activated Sludge ◽  
Toxic Effect ◽  
Sequencing Batch Reactor ◽  
Batch Reactor ◽  
Load Level ◽  
Tolerance Range ◽  
Activated Sludge System ◽  
Process System ◽  
Final Effluent ◽  
Change Curve

Aiming at the toxic effect of Cr3+ on the activated sludge in sequencing batch reactor (SBR) process system, the article researched the toxic effect of Cr3+ on activated sludge and sewage processing in SBR process system through detecting the COD changes of SBR activated sludge with different chromium loads and different initial SVIs. The results show that when chromium load level is lower than 12.5mgCr3+/g mlvss, Cr3+ can promote activated sludge to adsorb organic substance COD. The effect is affected by the initial SVI which exerts impact on the toxic effect of chromium load on activated sludge within the tolerance range. When it is within the non-tolerance range, the final effluent COD of the system increase apparently. In the process, COD change curve is rather gentle; and the time of arriving at a rather low COD is relatively delayed. The system tolerance of chrome toxicity with a low initial SVI is comparatively strong.

scholarly journals Performance of Novel Contact Stabilization Activated Sludge System on Domestic Wastewater Treatment

2015 ◽  
Vol 19 (2) ◽  
pp. 7
Author(s):  
Andrés Felipe Torres Franco ◽  
Nancy Vásquez Sarria ◽  
Jenny Rodriguez Victoria
Keyword(s):  
Activated Sludge ◽  
Oxygen Demand ◽  
Domestic Wastewater ◽  
Growth Zone ◽  
Pilot Scale ◽  
Ammonia Nitrogen ◽  
Activated Sludge System ◽  
Suspended Growth ◽  
Removal Efficiencies ◽  
Final Effluent

A pilot-scale study was conducted to evaluate a traditional contact stabilization activated sludge system (CSASC) and a modified CSAS (CSASM) treating domestic wastewater. The CSASC system was comprised of a contact reactor (CR), a stabilization reactor (SR) and a secondary settler (SS); the CSASM included a second CR, a second SS (CR2 and SS2), and a modified SR (SRM) divided into four zones: an attached-suspended growth zone which allowed the system to reach an average sludge retention time close to 36 d and favored the occurrence of nitrification; an anoxic zone for denitrification occurrence; an aerated suspended growth zone with a high presence of organic carbon; and an additional aerated suspended growth zone with a high ammonia concentrations environment. The CSASC’s removal efficiencies of chemical oxygen demand (COD) and total ammonia nitrogen (TAN) were respectively 94±4 % and 53±12%; whereas CSASM’s efficiencies were 88±7% for COD and 92±7% for TAN. Concentrations of TAN and NO3 --N in the CSASC’s final effluent were 14.3±5.2 and 5.0±2.9 mg×L-1; and 4.8±4.4 and 9.1±5.8 mg×L-1 in the CSASM’s final effluent. Results demonstrated that the proposed configuration obtained higher nitrogen removal efficiencies than traditional CSAS.</p>

Study on the Performance Efficiency of A2/O Humic Activated Sludge System Operating in Low Temperature

2011 ◽  
Vol 281 ◽  
pp. 187-190 ◽  
Author(s):  
Jun Yin ◽  
Lei Wu ◽  
Yu Juan Yu ◽  
Ju Kui Zhang ◽  
Ke Zhao ◽  
...  
Keyword(s):  
Low Temperature ◽  
Activated Sludge ◽  
Removal Efficiency ◽  
Phosphorus Removal ◽  
Removal Rate ◽  
Sewage Discharge ◽  
High Phosphorus ◽  
Activated Sludge System ◽  
Article Analysis ◽  
System Operating

In this article, analysis the A2/O humic activated sludge system phosphorus removal efficiency and CODCr removal efficiency at 5°C, 10°C and 25°C. The results show that A2/O humic activated sludge system phosphorus removal rate when the influent temperature is above 10°C maintained at 86.1% ~ 97.5% performed high phosphorus removal efficiency. But at 5°C the system’s phosphorus removal efficiency decreased to 58.31% couldn’t get the sewage discharge standard. The variation of influent temperature had little influence on the removal efficiency of CODCr even at 5°C performed high removal efficiency.

Investigation of textile dyeing effluent using activated sludge system to assess the removal efficiency

2021 ◽  
Author(s):  
Ahmed Malik ◽  
Maham Hussain ◽  
Fahim Uddin ◽  
Waseem Raza ◽  
Sadiq Hussain ◽  
...  
Keyword(s):  
Activated Sludge ◽  
Removal Efficiency ◽  
Activated Sludge System ◽  
Textile Dyeing ◽  
Dyeing Effluent

Dyeing wastewater treatment by activated sludge process with a polyurethane fluidized bed biofilm

1996 ◽  
Vol 34 (5-6) ◽  
pp. 193-200 ◽  
Author(s):  
Yung-Kyu Park ◽  
Chul-Hee Lee
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Fluidized Bed ◽  
Removal Efficiency ◽  
Biomass Yield ◽  
Biological Process ◽  
Activated Sludge Process ◽  
Dyeing Wastewater ◽  
Coagulation Process ◽  
Final Effluent

In case of the porous polyurethane fluidized bed biofilm-activated sludge process followed by a coagulation process(the FBAS-C process), 75% CODMn was removed by treating with the biological FBAS process in the loading range of 0.16∼0.32 kgCODMn/kgVSS·day. The biomass yield and microbial decay coefficients were 0.42 kg MLSS/kgBOD and 0.11 day−1, respectively. The optimum coagulation conditions for the effluent of the FBAS process were at pH 6 and 600mg/L alum dosage. Consequently, 92% of total CODMn removal efficiency was observed in the FBAS-C process. Meanwhile, in case of a coagulation process followed by the porous polyurethane fluidized bed biofilm-activated sludge process(C-FBAS process). the raw dyeing wastewater was treated at pH 6 in the presence of 1,000 mg/L alum and, continuously, the effluent coagulated wastewater was treated by the FBAS process in the loading range of 0.09∼0.19 kg CODMn/kgVSS·day. Removal efficiency of CODMn in the biological process, FBAS, was 82%. The biomass yield and microbial decay coefficient in the C-FBAS process were similar to those in the FBAS-C process. The final effluent CODMn was about 65 mg/L in both tested processes, the FBAS-C and C-FBAS. However, the FBAS-C process illustrated better treatibility than C-FBAS in terms of the total sludge production, since the former produced about 20% less sludge than the latter.

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