Partial nitritation of stored source-separated urine by granular activated sludge in a sequencing batch reactor

An anaerobic enrichment culture was developed from an anoxic/anaerobic/aerobic activated sludge sequencing batch reactor using methyl ethyl ketoxime (MEKO), a potent nitrification inhibitor, as the sole carbon and energy source in the absence of molecular oxygen and nitrate. The enrichment culture was gradually fed decreasing amounts of biogenic organic compounds and increasing concentrations of MEKO over 23 days until the cultures metabolized the oxime as the sole carbon source; the cultures were maintained for an additional 41 days on MEKO alone. Turbidity stabilized at approximately 100 mg/l total suspended solids. Growth on selective media plates confirmed that the microorganisms were utilizing the MEKO as the sole carbon and energy source. The time frame required for growth indicated that the kinetics for MEKO degradation are slow. A batch test indicated that dissolved organic carbon decreased at a rate comparable to MEKO consumption, while sulfate was not consumed. The nature of the electron acceptor in anaerobic MEKO metabolism is unclear, but it is hypothesized that the MEKO is hydrolyzed intracellularly to form methyl ethyl ketone and hydroxylamine which serve as electron donor and electron acceptor, respectively.

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Excess nitrogen accumulation in activated sludge in sequencing batch reactor with a single-stage oxic process

Water Science & Technology ◽

10.2166/wst.2009.003 ◽

2009 ◽

Vol 59 (3) ◽

pp. 573-582 ◽

Cited By ~ 3

Author(s):

Xiao-ming Li ◽

Dong-bo Wang ◽

Qi Yang ◽

Wei Zheng ◽

Jian-bin Cao ◽

...

Keyword(s):

Activated Sludge ◽

Nitrogen Removal ◽

Sequencing Batch Reactor ◽

Ph Value ◽

Batch Reactor ◽

Nitrogen Loss ◽

Single Stage ◽

Synthetic Wastewater ◽

Nitrogen Accumulation ◽

Excess Nitrogen

It was occasionally found that a significant nitrogen loss in solution under neutral pH value in a sequencing batch reactor with a single-stage oxic process using synthetic wastewater, and then further studies were to verify the phenomenon of nitrogen loss and to investigate the pathway of nitrogen removal. The result showed that good performance of nitrogen removal was obtained in system. 0–7.28 mg L−1 ammonia, 0.08–0.38 mg L−1 nitrite and 0.94–2.12 mg L−1 nitrate were determined in effluent, respectively, when 29.85–35.65 mg L−1 ammonia was feeding as the sole nitrogen source in influent. Furthermore, a substantial nitrogen loss in solution (95% of nitrogen influent) coupled with a little gaseous nitrogen increase in off-gas (7% of nitrogen influent) was determined during a typical aerobic phase. In addition, about 322 mg nitrogen accumulation (84% of nitrogen influent) was detected in activated sludge. Based on nitrogen mass balance calculation, the unaccounted nitrogen fraction and the ratio of nitrogen accumulation in sludge/nitrogen loss in solution were 14.6 mg (3.7% of nitrogen influent) and 0.89, respectively. The facts indicated that the essential pathway of nitrogen loss in solution in this study was excess nitrogen accumulation in activated sludge.

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Effects of adsorbents and copper(II) on activated sludge microorganisms and sequencing batch reactor treatment process

Journal of Hazardous Materials ◽

10.1016/j.jhazmat.2003.07.008 ◽

2003 ◽

Vol 103 (3) ◽

pp. 263-277 ◽

Cited By ~ 31

Author(s):

S.A Ong ◽

P.E Lim ◽

C.E Seng

Keyword(s):

Activated Sludge ◽

Sequencing Batch Reactor ◽

Treatment Process ◽

Batch Reactor

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Advanced Treatment of Domestic Wastewater Using Sequencing Batch Reactor Activated Sludge Process

Water Science & Technology ◽

10.2166/wst.1993.0243 ◽

1993 ◽

Vol 28 (10) ◽

pp. 267-274 ◽

Cited By ~ 6

Author(s):

M. Imura ◽

E. Suzuki ◽

T. Kitao ◽

S. Iwai

Keyword(s):

Activated Sludge ◽

Sequencing Batch Reactor ◽

Batch Reactor ◽

Domestic Wastewater ◽

Experimental Period ◽

Small Scale ◽

Experimental Plant ◽

Activated Sludge Process ◽

Nitrogen And Phosphorus ◽

Experimental Apparatus

In order to apply a sequencing batch reactor activated sludge process to small scale treatment facilities, various experiments were conducted by manufacturing an experimental apparatus made of a factory-produced FRP cylinder transverse tank (Ø 2,500mm). Results of the verification test conducted for one year by leading the wastewater discharged from apartment houses into the experimental apparatus were as follows. Excellent performance was achieved without any addition of carbon source, irrespective of the organic compound concentration and the temperature of raw wastewater. Organic substances, nitrogen and phosphorus were removed simultaneously. Due to the automated operation format, stable performance was obtained with only periodic maintenance. Though water depth of the experimental plant was shallow, effective sedimentation of activated sludge was continued during the experimental period. Regarding the aerobic and anaerobic process, nitrification and denitrification occurred smoothly.

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Dynamic control of nutrient-removal from industrial wastewater in a sequencing batch reactor, using common and low-cost online sensors

Water Science & Technology ◽

10.2166/wst.2015.553 ◽

2015 ◽

Vol 73 (4) ◽

pp. 740-745 ◽

Cited By ~ 7

Author(s):

Jan Dries

Keyword(s):

Activated Sludge ◽

Nutrient Removal ◽

Industrial Wastewater ◽

Sequencing Batch Reactor ◽

Batch Reactor ◽

Low Cost ◽

Dynamic Control ◽

Oxygen Demand ◽

Oxidation Reduction ◽

Oxidation Reduction Potential

On-line control of the biological treatment process is an innovative tool to cope with variable concentrations of chemical oxygen demand and nutrients in industrial wastewater. In the present study we implemented a simple dynamic control strategy for nutrient-removal in a sequencing batch reactor (SBR) treating variable tank truck cleaning wastewater. The control system was based on derived signals from two low-cost and robust sensors that are very common in activated sludge plants, i.e. oxidation reduction potential (ORP) and dissolved oxygen. The amount of wastewater fed during anoxic filling phases, and the number of filling phases in the SBR cycle, were determined by the appearance of the ‘nitrate knee’ in the profile of the ORP. The phase length of the subsequent aerobic phases was controlled by the oxygen uptake rate measured online in the reactor. As a result, the sludge loading rate (F/M ratio), the volume exchange rate and the SBR cycle length adapted dynamically to the activity of the activated sludge and the actual characteristics of the wastewater, without affecting the final effluent quality.

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Partial nitritation treating nitrogen in old landfill leachate

Science and Technology Development Journal ◽

10.32508/stdj.v19i4.592 ◽

2016 ◽

Vol 19 (4) ◽

pp. 39-49

Author(s):

Nhat The Phan ◽

Van Thi Thanh Truong ◽

Son Thanh Le ◽

Biec Nhu Ha ◽

Dan Phuoc Nguyen

Keyword(s):

Landfill Leachate ◽

Retention Time ◽

Sequencing Batch Reactor ◽

Hydraulic Retention Time ◽

Batch Reactor ◽

Partial Nitritation ◽

Time Operation ◽

Nitrite Oxidizing Bacteria ◽

Long Time ◽

H 30

In this study, a lab-scale Partial Nitritation Sequencing Batch Reactor (PNSBR) was implemented for treating high-ammonium old landfill leachate to yield an appropriate NO2—N/ NH4+-N ratio from 1/1 to 1.32/1 mixture as a pretreatment for subsequent Anammox. The objective of this study was to determine the optimal hydraulic retention time (HRT) at different influent ammonia concentrations for 210 days. The experimental results showed that with the influent ammonia concentrations of 500, 1000, 1500 and 2000 mg/L, HRT is 12 h, 21 h, 30 h and 48 h, respectively. The range of free ammonia (FA) concentration from 17 to 44 mg/L completely inhibited nitrite oxidizing bacteria (NOB) for long time operation. The COD removal efficiency was very low (6±2) %.

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