Settleability and kinetics of a nitrifying sludge in a sequencing batch reactor

2004 ◽  
Vol 50 (11) ◽  
pp. 943-949 ◽  
Author(s):  
A -C Texier ◽  
J Gomez
Keyword(s):  
Sequencing Batch Reactor ◽  
Batch Reactor ◽  
Operation Time ◽  
Volume Index ◽  
Specific Rate ◽  
Ammonia Oxidizing Bacteria ◽  
Microbial Protein ◽  
N Accumulation ◽  
Reactor Kinetics ◽  
Nitrite Oxidizing Bacteria

A physiological study of a nitrifying sludge was carried out in a sequencing batch reactor (SBR). Pseudo steady-state nitrification conditions were obtained with an ammonium removal efficiency of 99% ± 1% and 98% ± 2% conversion of NH4+-N to NO3–-N. The rate of biomass production was negligible (1.3 ± 0.1 mg microbial protein-N·L–1·d–1). The sludge presented good settling properties with sludge volume index values lower than 20 mL·g–1 and an exopolymeric protein/carbohydrate ratio of 0.53 ± 0.34. Kinetic results indicated that the nitrifying behavior of the sludge changed with the number of cycles. After 22 cycles, a decrease in the specific rate of NO3–-N production coupled with an increase in the NO2–-N accumulation were observed. These results showed that the activity of the nitrite oxidizing bacteria decreased at a longer operation time. Ammonia oxidizing bacteria were found to exhibit the best stability. After 4 months of operation, the specific rates of NH4+-N consumption and NO3–-N production were 1.72 NH4+-N per microbial protein-N per hour (g·g–1·h–1) and 0.54 NO3–-N per microbial protein-N per hour (g·g–1·h–1), respectively.Key words: nitrification, sequencing batch reactor, kinetics, settleability, exopolymeric substances.

Post-treatment of a slaughterhouse wastewater: stability of the microbial community of a sequencing batch reactor operated under oxygen limited conditions

2006 ◽  
Vol 54 (2) ◽  
pp. 215-221 ◽  
Author(s):  
A. Cabezas ◽  
P. Draper ◽  
L. Muxí ◽  
C. Etchebehere
Keyword(s):  
Microbial Community ◽  
Organic Nitrogen ◽  
Sequencing Batch Reactor ◽  
Batch Reactor ◽  
Anaerobic Treatment ◽  
Post Treatment ◽  
Ammonia Oxidizing Bacteria ◽  
Slaughterhouse Wastewater ◽  
Nitrite Oxidizing Bacteria ◽  
The Stability

Slaughterhouse wastewater is a complex effluent with an important content of organic nitrogen. After an anaerobic treatment where most of the organic matter is removed, the nitrogen, remains as ammonium and post-treatment of the effluent is necessary. Sequencing batch reactor (SBR) technology has been developed to completely remove nitrogen in one single reactor combining aerobic and anoxic stages. Under oxygen limited conditions only nitrite is produced with concomitant energy saving. The stability and diversity of the microbial community from a nitrifying denitrifying SBR operated under oxygen limited conditions were studied using molecular and respirometric methods. The AOB (ammonia oxidizing bacteria) community was relatively stable Nitrosomonas being the dominant genera although Nitrosospira and Nitrosococcus were detected in low proportions. Nitrite oxidizing bacteria were out competed during the operation under oxygen-limited conditions. After an increase of the DO in the reactor Nitrobacter spp were detected suggesting that they remained in the system. Changes in the AOB and denitrifying communities were observed after the DO increase. Sedimentation problems were detected during operation, this could be related to the predominance of Thauera spp detected by FISH and T-RFLP.

The kinetics for ammonium and nitrite oxidation under the effect of hydroxylamine

2015 ◽  
Vol 73 (5) ◽  
pp. 1067-1073 ◽  
Author(s):  
Xinyu Wan ◽  
Pengying Xiao ◽  
Daijun Zhang ◽  
Peili Lu ◽  
Zongbao Yao ◽  
...  
Keyword(s):  
Sequencing Batch Reactor ◽  
Ammonia Oxidation ◽  
Oxygen Uptake Rate ◽  
Batch Reactor ◽  
Ammonia Oxidizing Bacteria ◽  
Nitrite Oxidation ◽  
Kinetics Parameters ◽  
Nitrification Process ◽  
Nitrite Oxidizing Bacteria ◽  
No2 Oxidation

The kinetics for ammonium (NH4+) oxidation and nitrite (NO2−) oxidation under the effect of hydroxylamine (NH2OH) were studied by respirometry using the nitrifying sludge from a laboratory-scale sequencing batch reactor. Modified models were used to estimate kinetics parameters of ammonia and nitrite oxidation under the effect of hydroxylamine. An inhibition effect of hydroxylamine on the ammonia oxidation was observed under different hydroxylamine concentration levels. The self-inhibition coefficient of hydroxylamine oxidation and noncompetitive inhibition coefficient of hydroxylamine for nitrite oxidation was estimated by simulating exogenous oxygen-uptake rate profiles, respectively. The inhibitive effect of NH2OH on nitrite-oxidizing bacteria was stronger than on ammonia-oxidizing bacteria. This work could provide fundamental data for the kinetic investigation of the nitrification process.

scholarly journals Partial nitritation treating nitrogen in old landfill leachate

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) %.

scholarly journals Co-treatment of old landfill leachate and municipal wastewater in sequencing batch reactor (SBR): effect of landfill leachate concentration

2016 ◽  
Vol 51 (4) ◽  
pp. 377-387 ◽  
Author(s):  
Kshitij Ranjan ◽  
Shubhrasekhar Chakraborty ◽  
Mohini Verma ◽  
Jawed Iqbal ◽  
R. Naresh Kumar
Keyword(s):  
Removal Efficiency ◽  
Landfill Leachate ◽  
Suspended Solids ◽  
Sequencing Batch Reactor ◽  
Municipal Wastewater ◽  
Batch Reactor ◽  
Operating Conditions ◽  
Volume Index ◽  
Turbidity Removal ◽  
Mixed Liquor

Sequencing batch reactor (SBR) was assessed for direct co-treatment of old landfill leachate and municipal wastewater for chemical oxygen demand (COD), nutrients and turbidity removal. Nitrogen removal was achieved by sequential nitrification and denitrification under post-anoxic conditions. Initially, SBR operating conditions were optimized by varying hydraulic retention time (HRT) at 20% (v/v) landfill leachate concentration, and results showed that 6 d HRT was suitable for co-treatment. SBR performance was assessed in terms of COD, ammonia, nitrate, phosphate, and turbidity removal efficiency. pH, mixed liquor suspended solids, mixed liquor volatile suspended solids (MLVSS), and sludge volume index were monitored to evaluate stability of SBR. MLVSS indicated that biomass was able to grow even at higher concentrations of old landfill leachate. Ammonia and nitrate removal efficiency was more than 93% and 83%, respectively, whereas COD reduction was in the range of 60–70%. Phosphate and turbidity removal efficiency was 80% and 83%, respectively. Microbial growth kinetic parameters indicated that there was no inhibition of biomass growth up to 20% landfill leachate. The results highlighted that SBR can be used as an initial step for direct co-treatment of landfill leachate and municipal wastewater.

scholarly journals The treatment of solvent recovery raffinate by aerobic granular sludge in a pilot-scale sequencing batch reactor

2015 ◽  
Vol 13 (3) ◽  
pp. 746-757 ◽  
Author(s):  
Bei Long ◽  
Chang-zhu Yang ◽  
Wen-hong Pu ◽  
Jia-kuan Yang ◽  
Guo-sheng Jiang ◽  
...  
Keyword(s):  
Suspended Solids ◽  
Sequencing Batch Reactor ◽  
Batch Reactor ◽  
Granular Sludge ◽  
Pilot Scale ◽  
Volume Index ◽  
Aerobic Granular Sludge ◽  
Average Particle ◽  
Solvent Recovery ◽  
Mixed Liquor

Mature aerobic granular sludge (AGS) was inoculated for the start-up of a pilot-scale sequencing batch reactor for the treatment of high concentration solvent recovery raffinate (SRR). The proportion of simulated wastewater (SW) (w/w) in the influent gradually decreased to zero during the operation, while volume of SRR gradually increased from zero to 10.84 L. AGS was successfully domesticated after 48 days, which maintained its structure during the operation. The domesticated AGS was orange, irregular, smooth and compact. Sludge volume index (SVI), SV30/SV5, mixed liquor volatile suspended solids/mixed liquor suspended solids (MLVSS/MLSS), extracellular polymeric substances, proteins/polysaccharides, average particle size, granulation rate, specific oxygen utilization rates (SOUR)H and (SOUR)N of AGS were about 38 mL/g, 0.97, 0.52, 39.73 mg/g MLVSS, 1.17, 1.51 mm, 96.66%, 47.40 mg O2/h g volatile suspended solids (VSS) and 8.96 mg O2/h g VSS, respectively. Good removal effect was achieved by the reactor. Finally, the removal rates of chemical oxygen demand (COD), total inorganic nitrogen (TIN), NH4+-N and total phosphorus (TP) were more than 98%, 96%, 97% and 97%, respectively. The result indicated gradually increasing the proportion of real wastewater in influent was a useful domestication method, and the feasibility of AGS for treatment of high C/N ratio industrial wastewater.

Use of image analysis and rheological studies for the control of settleability of filamentous bacteria: application in SBR reactor

2001 ◽  
Vol 43 (3) ◽  
pp. 27-33 ◽  
Author(s):  
C. Dagot ◽  
M. N. Pons ◽  
M. Casellas ◽  
G. Guibaud ◽  
P. Dollet ◽  
...  
Keyword(s):  
Image Analysis ◽  
Sequencing Batch Reactor ◽  
Batch Reactor ◽  
Automated Image Analysis ◽  
Volume Index ◽  
Filamentous Bacteria ◽  
Sludge Volume Index ◽  
Floc Size ◽  
First Results

To monitor the ability of flocs to settle in Sequencing Batch Reactor sludge, two methods were tested during two operation cycles. Firstly, an automated image analysis procedure has been tested to quantify the floc size and the length and number of filaments. Secondly, rheological measurements (Bingham viscosity and shear stress) have been used to characterise the dispersion of the sludge which can reflect the cohesive strength of aggregates and so the influence of filamentous bacteria on rheological properties. These results were compared with settling parameters such as Sludge Volume Index or settling velocity. Correlations between the measured parameters with image analysis and parameters such as Sludge Volume Index have been obtained. If it is more difficult to analyze rheological results, it seems however that the thixotropy and the Bingham viscosity distinguish poor settlement owing to some filamentous bulking. The first results are promising, although they require confirmation in the long term.

Cultivation of polyhydroxybutyrate-rich aerobic granular sludge in a sequencing batch reactor

2006 ◽  
Vol 6 (6) ◽  
pp. 81-87 ◽  
Author(s):  
J. Wang ◽  
H.Q. Yu
Keyword(s):  
Sequencing Batch Reactor ◽  
Batch Reactor ◽  
Granular Sludge ◽  
Volume Index ◽  
Synthetic Wastewater ◽  
Aerobic Granular Sludge ◽  
Second Step ◽  
Sludge Volume Index ◽  
Flat Shape ◽  
Sludge Granulation

In this study a two-step strategy was adopted to cultivate Polyhydroxybutyrate (PHB)-rich aerobic granular sludge in a sequencing batch reactor (SBR) fed with a synthetic wastewater. In the first step both oxygen and ammonia were initially limited, in order to enhance the PHB-storage ability of sludge. In the second step granular sludge was cultivated to get a high PHB volumetric productivity. The PHB content of sludge increased to 43.1±2.0% in the first step. During the sludge granulation, the PHB content was constant at 40±4.6%. With the granulation, the settling ability of the PHB-rich sludge continuously improved, as evidenced by a decreased sludge volume index. The matured PHB-rich granular sludge presented a buff color and regular morphology with elliptical and flat shape.

Partial Nitrification to Nitrite with Real-Time Aeration Duration Control in an SBR Treating Domestic Wastewater

2011 ◽  
Vol 356-360 ◽  
pp. 1046-1049 ◽  
Author(s):  
Yu Chen ◽  
Jun Li ◽  
C .W Wang ◽  
X.F Zhao ◽  
B.H Zhao
Keyword(s):  
Real Time ◽  
Batch Reactor ◽  
Domestic Wastewater ◽  
Partial Nitrification ◽  
Nitrite Accumulation ◽  
Ammonia Oxidizing Bacteria ◽  
Term Operation ◽  
Nitrite Oxidizing Bacteria ◽  
Low Strength

Sustainable partial nitrification to nitrite has been proven difficult in treating low strength nitrogenous wastewater. Real-time aeration duration control was used to achieve efficient partial nitrification to nitrite in a sequencing batch reactor (SBR) to treat low strength domestic wastewater. Above 95% nitrite accumulation ratio was maintained for long-term operation at normal condition. Partial nitrification established by controlling aeration duration showed good performance and robustness even though some time encountering long-term extended aeration. Process control enhanced the successful accumulation of ammonia oxidizing bacteria (AOB) and washout of nitrite oxidizing bacteria (NOB).

Aerobic granular sludge: a promising technology for decentralised wastewater treatment

2006 ◽  
Vol 53 (9) ◽  
pp. 79-85 ◽  
Author(s):  
Z.H. Li ◽  
T. Kuba ◽  
T. Kusuda
Keyword(s):  
Sequencing Batch Reactor ◽  
Loading Rate ◽  
Batch Reactor ◽  
Granular Sludge ◽  
Volume Index ◽  
Synthetic Wastewater ◽  
Aerobic Granular Sludge ◽  
Organic Loading Rate ◽  
Organic Loading ◽  
Fast Settling

In order to evaluate the characteristics of aerobic granular sludge, a sequencing batch reactor, feeding with synthetic wastewater at the organic loading rate of 8 kg COD/m3 d, was employed on the laboratory scale. Granules occurred in the reactor within 1 week after the inoculation from conventional flocculent sludge. Aerobic granular sludge was characterised by the outstanding settling properties and considerable contaminates removal efficiencies. The SVI30 values were in the range of 20 to 40 ml g−1. However, the sludge volume index of short settling time (e.g. SVI10 – 10 min) is suggested to describe the fast settling properties of aerobic granular sludge. The potential application in the decentralised system is evaluated from the point view of footprint and high bioactivity. The occurrence of sloughing, resulting from the outgrowth of filamentous organisms, would be responsible for the instability of aerobic granules. The starvation phase should therefore be carefully controlled for the maintenance and stability of aerobic granular sludge system.

Sign in / Sign up

Export Citation Format

Share Document