scholarly journals Perspectives of intracellular polymers in functional evaluation of the microbes for EBPR

2021 ◽  
Author(s):  
Ghazal Srivastava ◽  
Absar Ahmad Kazmi
Keyword(s):  
Evaluation Studies ◽  
Oxygen Demand ◽  
Cyclic Behavior ◽  
Batch Reactors ◽  
Functional Evaluation ◽  
Sequencing Batch Reactors ◽  
Biological Phosphorus Removal ◽  
Biochemical Processes ◽  
Sudan Black B ◽  
Wastewater Quality

Abstract To substantiate and interpret the performance of the Enhanced Biological Phosphorus Removal (EBPR) processes with simultaneous nitrogen removal in five full-scale sequencing batch reactors (SBR) systems (with or without pre-anoxic/anaerobic selector) across India, conventional microscopic examinations were performed. Regular examining and cyclic behavior evaluation studies specified that these systems worked for EBPR with effectiveness depending on the wastewater quality and operational steadiness. Treatment with Neisser stain for identifying polyphosphates (poly-P) and Sudan black B stain for observing poly-β-hydroxybutyrates (PHB) granules showed that the enriched biomass of the SBR plants was very diverse concerning morphology, residing populations of traditional rod-shaped PAOs, tetrad (or Sarcina-like cells) forming organisms (submitted as TFOs instead of GAOs), diplococci-shaped cells, and staphylococci-like clustered populations (CC), including few filaments which correlate well with biochemical processes undergoing in SBR plants. SBR plants with readily biodegradable chemical oxygen demand (rbCOD) fraction in COD > 16% and rbCOD/TP ∼10–20 in Varanasi, Mumbai, and Gurgaon, respectively, have performed for >20% EBPR (∼77.8%, ∼76.6%, and ∼84.8% TP removal, respectively) as well as >85% Simultaneous Nitrification and Denitrification (SND). This study can open novel dimensions for optimization by relating microscopic observations (qualitative examination) with the processes undergoing in the plants under varied physicochemical parameters.

scholarly journals Analysis of the Bioaugmentation Potential of Pseudomonas putida OR45a and Pseudomonas putida KB3 in the Sequencing Batch Reactors Fed with the Phenolic Landfill Leachate

Water ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 906
Author(s):  
Justyna Michalska ◽  
Artur Piński ◽  
Joanna Żur ◽  
Agnieszka Mrozik
Keyword(s):  
Pseudomonas Putida ◽  
Landfill Leachate ◽  
Oxygen Demand ◽  
Ammonia Nitrogen ◽  
Batch Reactors ◽  
Sequencing Batch Reactors ◽  
High Toxicity ◽  
High Enzymatic Activity ◽  
Wastewater Treatment Systems ◽  
Nonspecific Esterases

The treatment of landfill leachate could be challenging for the biological wastewater treatment systems due to its high toxicity and the presence of poorly biodegradable contaminants. In this study, the bioaugmentation technology was successfully applied in sequencing batch reactors (SBRs) fed with the phenolic landfill leachate by inoculation of the activated sludge (AS) with two phenol-degrading Pseudomonas putida OR45a and Pseudomonas putida KB3 strains. According to the results, the SBRs bioaugmented with Pseudomonas strains withstood the increasing concentrations of the leachate. This resulted in the higher removal efficiency of the chemical oxygen demand (COD) of 79–86%, ammonia nitrogen of 87–88% and phenolic compounds of 85–96% as compared to 45%, 64%, and 50% for the noninoculated SBR. Simultaneously, the bioaugmentation of the AS allowed to maintain the high enzymatic activity of dehydrogenases, nonspecific esterases, and catalase in this ecosystem, which contributed to the higher functional capacity of indigenous microorganisms than in the noninoculated AS. Herein, the stress level experienced by the microorganisms in the SBRs fed with the leachate computed based on the cellular ATP measurements showed that the abundance of exogenous Pseudomonas strains in the bioreactors contributed to the reduction in effluent toxicity, which was reflected by a decrease in the stress biomass index to 32–45% as compared to the nonbioaugmented AS (76%).

Occurrence of Microthrix parvicella in sequencing batch reactors

2014 ◽  
Vol 69 (10) ◽  
pp. 1984-1995 ◽  
Author(s):  
Lana Mallouhi ◽  
Ute Austermann-Haun
Keyword(s):  
Activated Sludge ◽  
Municipal Wastewater ◽  
Batch Reactor ◽  
Oxygen Demand ◽  
Volume Index ◽  
Batch Reactors ◽  
Sequencing Batch Reactors ◽  
Municipal Wastewater Treatment ◽  
Nitrogen And Phosphorus ◽  
Microthrix Parvicella

Sequencing batch reactors (SBRs) are known for high process stability and usually have a good sludge volume index (SVI). Nevertheless, in many SBRs in Germany for municipal wastewater treatment, scum and foam problems can occur, and SVI can be larger than 200 mL/g. The microscopic investigations of the activated sludge from plants with nitrogen and phosphorus removal have shown that Microthrix parvicella is dominant in the activated sludge in most of them. Studies showed that the optimum growth of M. parvicella is performed at a high sludge age (>20 d) and low sludge load in the range of 0.05–0.2 kg of biochemical oxygen demand per kg of total suspended solids per day (kg BOD5/(TSS·d)). The investigations in 13 SBRs with simultaneous aerobic sludge stabilization (most of them are operated with a system called differential internal cycle strategy sequential batch reactor (DIC-SBR)) show that M. parvicella is able to grow in sludge loads less than 0.05 kg BOD5/(kg TSS·d) as well. To optimize the operation of those SBRs, long cycle times (8–12 h) and dosing of iron salts to eliminate long-chain fatty acids are both recommended. This leads to better SVI and keeps M. parvicella at a low frequency.

Effect of sludge discharge positions on steady-state aerobic granules in sequencing batch reactor (SBR)

2012 ◽  
Vol 66 (8) ◽  
pp. 1722-1727 ◽  
Author(s):  
Lin Liu ◽  
Da-Wen Gao ◽  
Hong Liang
Keyword(s):  
Steady State ◽  
Batch Reactor ◽  
Oxygen Demand ◽  
Aerobic Granule ◽  
Stable Operation ◽  
Batch Reactors ◽  
Aerobic Granules ◽  
Sequencing Batch Reactors ◽  
Discharge Location

We have investigated the effect of sludge discharge location on the steady-state aerobic granules in sequencing batch reactors (SBRs). Two SBRs were operated concurrently with the same sludge retention time using sludge discharge ports at: (a) the reactor bottom in R1; and (b) the reactor middle-lower level in R2. Results indicate that both reactors could maintain sludge granulation and stable operation, but the two different sludge discharge methods resulted in significantly different aerobic granule characteristics. Over 30 days, the chemical oxygen demand (COD) removal of the two reactors was maintained at similar levels (above 96%), and typical bioflocs were not observed. The average aerobic granule size in R2 was twice that in R1, as settling velocity increased in proportion to size increment. Meanwhile, the production yields of polysaccharide and protein content in R2 were always higher than those in R1. However, due to mass transfer limitations and the presence of anaerobes in the aerobic granule cores, larger granules had a tendency to disintegrate in R2. Thus, we conclude that a sludge discharge port situated at the reactor bottom is beneficial for aerobic granule stability, and enhances the potential for long-term aerobic granule SBR operation.

Co-treatment of landfill leachate in laboratory-scale sequencing batch reactors: analysis of system performance and biomass activity by means of respirometric techniques

2014 ◽  
Vol 69 (6) ◽  
pp. 1267-1274 ◽  
Author(s):  
M. Capodici ◽  
D. Di Trapani ◽  
G. Viviani
Keyword(s):  
Landfill Leachate ◽  
Oxygen Uptake Rate ◽  
Oxygen Demand ◽  
Domestic Wastewater ◽  
Ammonia Nitrogen ◽  
Synthetic Wastewater ◽  
Batch Reactors ◽  
Sequencing Batch Reactors ◽  
Population Average ◽  
Biomass Activity

Aged or mature leachate, produced by old landfills, can be very refractory; for this reason mature leachate is difficult to treat alone, but it can be co-treated with sewage or domestic wastewater. The aim of the study was to investigate the feasibility of leachate co-treatment with synthetic wastewater, in terms of process performance and biomass activity, by means of respirometric techniques. Two sequencing batch reactors (SBRs), named SBR1 and SBR2, were fed with synthetic wastewater and two different percentages of landfill leachate (respectively 10% and 50% v v−1 in SBR1 and SBR2). The results showed good chemical oxygen demand (COD) removal efficiency for both reactors, with average COD removals equal to 91.64 and 89.04% respectively for SBR1 and SBR2. Furthermore, both SBRs showed good ammonia-nitrogen (AN) removal efficiencies, higher than 60%, thus confirming the feasibility of leachate co-treatment with a readily biodegradable wastewater. Significant respiration rates were obtained for the heterotrophic population (average values of maximum oxygen uptake rate equal to 37.30 and 56.68 mg O2 L−1 h−1 respectively for SBR1 and SBR2), thus suggesting the feasibility of leachate co-treatment with synthetic wastewater.

Biological treatment of pharmaceutical wastewater from the antibiotics industry

2013 ◽  
Vol 69 (4) ◽  
pp. 855-861 ◽  
Author(s):  
O. Lefebvre ◽  
X. Shi ◽  
C. H. Wu ◽  
H. Y. Ng
Keyword(s):  
Loading Rate ◽  
Oxygen Demand ◽  
Organic Loading Rate ◽  
Batch Reactors ◽  
Sequencing Batch Reactors ◽  
Pharmaceutical Wastewater ◽  
Refractory Compounds ◽  
Treated Effluent ◽  
Discharge Regulation ◽  
Pre Treatment

Pharmaceutical wastewater generated by an antibiotics (penicillin) company was treated by aerobic membrane bioreactors (MBRs) and sequencing batch reactors (SBRs). At a low organic loading rate of 0.22 kg-COD m−3d−1, both types of reactors were capable of treating the wastewater such that the treated effluent met the discharge regulation except for the total dissolved solids. However, when the loading rate was increased to 2.92 kg-COD m−3d−1, foaming issues resulted in unstable performance. Overall, the MBRs achieved better solid removal but the SBRs performed better in regards to the degradation of aromatic compounds, as determined by UV absorbance (UVA). Finally, ozonation was applied on two different streams and showed promise on the strong stream – that corresponds to the formulation effluent and contains most of the biorefractory compounds. Ozonation successfully reduced the UVA, lowered the pH and increased the biochemical oxygen demand : chemical oxygen demand (BOD5 : COD) ratio of the strong stream. However, it was less efficient on the effluent having undergone pre-treatment by a biofilter due to a lack of selectivity towards refractory compounds.

Treatment of thermomechanical pulping condensate using thermophilic and mesophilic sequencing batch reactors

2010 ◽  
Vol 62 (11) ◽  
pp. 2527-2535 ◽  
Author(s):  
S. P. Langevin ◽  
B. Q. Liao
Keyword(s):  
Removal Efficiency ◽  
Water System ◽  
Oxygen Demand ◽  
Volume Index ◽  
Organic Loading Rate ◽  
Batch Reactors ◽  
Sequencing Batch Reactors ◽  
Paper Mills ◽  
Treated Effluent ◽  
Thermomechanical Pulping

In-mill thermophilic treatment of individual wastewater streams to achieve water system closure has received much attention in pulp and paper mills. Aerobic biological treatment of thermomechanical pulping (TMP) condensate was conducted using thermophilic (55°C) and mesophilic (35°C) sequencing batch reactors (SBRs) for a period of 143 days at a cyclic time of 6, 8 and 12 h. A soluble chemical oxygen demand (SCOD) removal efficiency of 77 to 91% was achieved, given an organic loading rate of 0.7–1.3 kg/m3 d. The COD removal efficiency of the thermophilic SBR was slightly lower than that of the mesophilic SBR. Majority of the soluble COD was removed by biodegradation with a small portion (9–13%) of soluble COD stripped by aeration. The settleability (sludge volume index) and the flocculating ability (effluent suspended solids) of thermophilic sludge were comparable to or slightly poorer than that of the mesophilic sludge. The level of filaments in thermophilic sludge was usually higher than that in mesophilic sludge. The results of the study indicate that both thermophilic and mesophilic SBRs can be successfully operated for in-mill treatment of TMP condensate. The treated effluent has the potential for subsequent reuse in the mill.

Monitoring pH and electric conductivity in an EBPR sequencing batch reactor

2004 ◽  
Vol 50 (10) ◽  
pp. 145-152 ◽  
Author(s):  
J. Serralta ◽  
L. Borrás ◽  
C. Blanco ◽  
R. Barat ◽  
A. Seco
Keyword(s):  
Electric Conductivity ◽  
Batch Reactor ◽  
Phosphorus Uptake ◽  
Phosphorus Release ◽  
Batch Reactors ◽  
Acid Uptake ◽  
Sequencing Batch Reactors ◽  
Biological Phosphorus Removal ◽  
Conductivity Increase ◽  
One Year

This paper presents laboratory-scale experimentation carried out to study enhanced biological phosphorus removal. Two anaerobic aerobic (A/O) sequencing batch reactors (SBR) have been operated during more than one year to investigate the information provided by monitoring pH and electric conductivity under stationary and transient conditions. Continuous measurements of these parameters allow detecting the end of anaerobic phosphorus release, of aerobic phosphorus uptake and of initial denitrification, as well as incomplete acetic acid uptake. These results suggest the possibility of using pH and electric conductivity as control parameters to determine the length of both anaerobic and aerobic phases in an A/O SBR. More valuable information provided by monitoring pH and electric conductivity is the relation between the amount of phosphorus released and the conductivity increase observed during the anaerobic stages and which group of bacteria (heterotrophic or polyphosphate accumulating) is carrying out the denitrification process.

Treatment of synthetic kraft evaporator condensate using thermophilic and mesophilic membrane aerated biofilm reactors

2010 ◽  
Vol 61 (7) ◽  
pp. 1749-1756 ◽  
Author(s):  
B. Q. Liao ◽  
M. R. Zheng ◽  
L. Ratana-Rueangsri
Keyword(s):  
Comparative Study ◽  
Chemical Oxygen Demand ◽  
Removal Efficiency ◽  
Oxygen Demand ◽  
Cod Removal ◽  
Batch Reactors ◽  
Sequencing Batch Reactors ◽  
Biofilm Reactors ◽  
Cod Removal Efficiency

A comparative study on the treatment of synthetic kraft evaporator condensate was conducted using thermophilic (55°C) and mesophilic (30°C) membrane aerated biofilm reactors (MABRs) and sequencing batch reactors (SBRs) for 8 months. Under tested conditions, a chemical oxygen demand (COD) removal efficiency of 80–95% was achieved with both thermophilic and mesophilic MABRs and SBRs. The COD removal efficiency of thermophilic MABR (80–90%) was slightly lower than that of the mesophilic MABR (85–95%) and the thermophilic SBR (90–95%). A significant amount (13–37%) of COD was stripped by conventional aeration in the SBRs, while stripping in MABRs was negligible. Simultaneous COD removal and denitrification were observed in the mesophilic MABR, while the thermophilic MABR contributed mainly for COD removal. Nitrification was not significant in both the thermophilic and mesophilic MABRs. The results suggest that treatment of kraft evaporator condensate is feasible with the use of both thermophilic and mesophilic MABRs in terms of COD removal with the advantages of negligible stripping.

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