Strength characteristics of aerobic granular sludge

2012 ◽  
Vol 65 (2) ◽  
pp. 309-316 ◽  
Author(s):  
A. Nor-Anuar ◽  
Z. Ujang ◽  
M. C. M. van Loosdrecht ◽  
M. K. de Kreuk ◽  
G. Olsson
Keyword(s):  
Granular Sludge ◽  
Aerobic Granular Sludge ◽  
Strength Analysis ◽  
Anaerobic Granular Sludge ◽  
Aerobic Granules ◽  
Sludge Flocs ◽  
Conventional Activated Sludge ◽  
Biomass Retention ◽  
Settling Characteristic ◽  
Fast Settling

Aerobic granular sludge has a number of advantages over conventional activated sludge flocs, such as cohesive and strong matrix, fast settling characteristic, high biomass retention and ability to withstand high organic loadings, all aspects leading towards a compact reactor system. Still there are very few studies on the strength of aerobic granules. A procedure that has been used previously for anaerobic granular sludge strength analysis was adapted and used in this study. A new coefficient was introduced, called a stability coefficient (S), to quantify the strength of the aerobic granules. Indicators were also developed based on the strength analysis results, in order to categorize aerobic granules into three levels of strength, i.e. very strong (very stable), strong (stable) and not strong (not stable). The results indicated that aerobic granules grown on acetate were stronger (high density: >150 g T SSL−1 and low S value: 5%) than granules developed on sewage as influent. A lower value of S indicates a higher stability of the granules.

Settling behaviour of aerobic granular sludge

2007 ◽  
Vol 56 (7) ◽  
pp. 55-63 ◽  
Author(s):  
A. Nor Anuar ◽  
Z. Ujang ◽  
M.C.M. van Loosdrecht ◽  
M.K. de Kreuk
Keyword(s):  
Activated Sludge ◽  
Batch Reactor ◽  
High Capacity ◽  
Granular Sludge ◽  
Aerobic Granular Sludge ◽  
Mechanical Mixing ◽  
Sludge Flocs ◽  
Conventional Activated Sludge ◽  
Biomass Retention ◽  
Sludge Settling

Aerobic granular sludge (AGS) technology has been extensively studied recently to improve sludge settling and behaviour in activated sludge systems. The main advantage is that aerobic granular sludge (AGS) can settle very fast in a reactor or clarifier because AGS is compact and has strong structure. It also has good settleability and a high capacity for biomass retention. Several experimental works have been conducted in this study to observe the settling behaviours of AGS. The study thus has two aims: (1) to compare the settling profile of AGS with other sludge flocs and (2) to observe the influence of mechanical mixing and design of the reactor to the settleability of AGS. The first experimental outcome shows that AGS settles after less than 5 min in a depth of 0.4 m compared to other sludge flocs (from sequencing batch reactor, conventional activated sludge and extended aeration) which takes more than 30 min. This study also shows that the turbulence from the mixing mechanism and shear in the reactor provides an insignificant effect on the AGS settling velocity.

Comparison of some characteristics of aerobic granules and sludge flocs from sequencing batch reactors

2007 ◽  
Vol 55 (8-9) ◽  
pp. 403-411 ◽  
Author(s):  
J. Li ◽  
K. Garny ◽  
T. Neu ◽  
M. He ◽  
C. Lindenblatt ◽  
...  
Keyword(s):  
Microbial Activity ◽  
Municipal Wastewater ◽  
Volume Fraction ◽  
Granular Sludge ◽  
Volume Index ◽  
Aerobic Granular Sludge ◽  
Batch Reactors ◽  
Aerobic Granules ◽  
Sequencing Batch Reactors ◽  
Sludge Flocs

Physical, chemical and biological characteristics were investigated for aerobic granules and sludge flocs from three laboratory-scale sequencing batch reactors (SBRs). One reactor was operated as normal SBR (N-SBR) and two reactors were operated as granular SBRs (G-SBR1 and G-SBR2). G-SBR1 was inoculated with activated sludge and G-SBR2 with granules from the municipal wastewater plant in Garching (Germany). The following major parameters and functions were measured and compared between the three reactors: morphology, settling velocity, specific gravity (SG), sludge volume index (SVI), specific oxygen uptake rate (SOUR), distribution of the volume fraction of extracellular polymeric substances (EPS) and bacteria, organic carbon and nitrogen removal. Compared with sludge flocs, granular sludge had excellent settling properties, good solid–liquid separation, high biomass concentration, simultaneous nitrification and denitrification. Aerobic granular sludge does not have a higher microbial activity and there are some problems including higher effluent suspended solids, lower ratio of VSS/SS and no nitrification at the beginning of cultivation. Measurement with CLSM and additional image analysis showed that EPS glycoconjugates build one main fraction inside the granules. The aerobic granules from G-SBR1 prove to be heavier, smaller and have a higher microbial activity compared with G-SBR2. Furthermore, the granules were more compact, with lower SVI and less filamentous bacteria.

The SBR and its biofilm application potentials

2004 ◽  
Vol 50 (10) ◽  
pp. 1-10 ◽  
Author(s):  
P.A. Wilderer ◽  
B.S. McSwain
Keyword(s):  
Activated Sludge ◽  
Batch Reactor ◽  
Granular Sludge ◽  
Aerobic Granular Sludge ◽  
Waste Streams ◽  
Sludge Flocs ◽  
Biofilm Reactors ◽  
Volatile Organic ◽  
High Level ◽  
Slow Growing

Twenty plus years of experience, innovation, and research in the field of biological wastewater treatment and biofilm applications lead to the conclusion that biofilms are in many cases more desirable in reactors than suspended activated sludge. Biofilm reactors can provide very long biomass residence times even when the hydraulic influent loading is low. This makes them particularly suitable when treatment requires slow growing organisms with poor biomass yield or when the wastewater concentration is too low to support growth of activated sludge flocs. Regardless of the settling characteristics of biological aggregates or the hydraulic influent loading the metabolic activity in the reactor can be maintained at a high level. This paper reviews the application of biofilms in sequencing batch reactor (SBR) systems to treat non-readily biodegradable substrates, volatile organic waste constituents, complex waste streams requiring co-metabolism, and particulate wastewaters. Recent research using the SBR to form aerobic granular sludge as a special application of biofilms is also discussed.

scholarly journals Settling properties of aerobic granular sludge (AGS) and aerobic granular sludge molasses (AGSM)

2018 ◽  
Vol 34 ◽  
pp. 02022
Author(s):  
Azlina Mat Saad ◽  
Farrah Aini Dahalan ◽  
Naimah Ibrahim ◽  
Sara Yasina Yusuf ◽  
Siti Aqlima Ahmad ◽  
...  
Keyword(s):  
Industrial Wastewater ◽  
Sequencing Batch Reactor ◽  
Settling Velocity ◽  
Batch Reactor ◽  
Granular Sludge ◽  
Aerobic Granular Sludge ◽  
X Ray ◽  
Conventional Activated Sludge ◽  
Physiological Structure ◽  
Granulation Technology

Aerobic granulation technology is applied to treat domestic and industrial wastewater. The Aerobic granular sludge (AGS) cultivated has strong properties that appears to be denser and compact in physiological structure compared to the conventional activated sludge. It offers rapid settling for solid:liquid separation in wastewater treatment. Aerobic granules were developed using sequencing batch reactor (SBR) with intermittent aerobic – anaerobic mode with 8 cycles in 24 hr. This study examined the settling velocity performance of cultivated aerobic granular sludge (AGS) and aerobic granular sludge molasses (AGSM). The elemental composition in both AGS and AGSM were determined using X-ray fluorescence (XRF). The results showed that AGSM has higher settling velocity 30.5 m/h compared to AGS.

scholarly journals Simultaneous nitrification and phosphate removal by bioaugmented aerobic granules treating a fluoroorganic compound

2021 ◽  
Author(s):  
Anouk F. Duque ◽  
Vânia S. Bessa ◽  
Udo van Dongen ◽  
Merle K. de Kreuk ◽  
Raquel B. R. Mesquita ◽  
...  
Keyword(s):  
Denaturing Gradient Gel Electrophoresis ◽  
Amoa Gene ◽  
Granular Sludge ◽  
Phosphate Removal ◽  
Aerobic Granular Sludge ◽  
Ammonia Oxidizing Bacteria ◽  
Aerobic Granules ◽  
N Removal ◽  
Nitrite Oxidizing Bacteria ◽  
Gradient Gel Electrophoresis

Abstract The presence of toxic compounds in wastewater can cause problems for organic matter and nutrient removal. In this study, the long term effect of a model xenobiotic, 2-fluorophenol (2-FP), on ammonia oxidizing bacteria (AOB), nitrite oxidizing bacteria (NOB) and phosphate accumulating organisms (PAO) in aerobic granular sludge was investigated. Phosphate (P) and ammonium (N) removal efficiencies were high (>93%) and, after bioaugmentation with 2-FP degrading strain FP1, 2-FP was completely degraded. Neither N nor P removal were affected by 50 mg L−1 of 2-FP in the feed stream. Changes in the aerobic granule bacterial communities were followed. Numerical analysis of the denaturing gradient gel electrophoresis (DGGE) profiles showed low diversity for the amoA gene with an even distribution of species. PAOs, including denitrifying PAO (dPAO), and AOB were present in the 2-FP degrading granules, although dPAO population decreased throughout the 444 days reactor operation. The results demonstrated that the aerobic granules bioaugmented with FP1 strain successfully removed N, P and 2-FP simultaneously.

scholarly journals Study on aerobic granular sludge formation in sequencing batch reactors for tapioca wastewater treatment

2013 ◽  
Vol 16 (1) ◽  
pp. 40-48
Author(s):  
Phuong Thi Thanh Nguyen ◽  
Phuoc Van Nguyen ◽  
Anh Cam Thieu
Keyword(s):  
Granular Sludge ◽  
Biomass Accumulation ◽  
Synthetic Wastewater ◽  
Aerobic Granular Sludge ◽  
Organic Loading Rate ◽  
Anaerobic Sludge ◽  
Batch Reactors ◽  
Aerobic Granules ◽  
Toxic Substances ◽  
Sequencing Batch Reactors

Aerobic granular sludge has attracted extensive interest of researchers since the 90s due to the advantages of aerobic granules such as good settling ability, high biomass accumulation, being resistant to high loads and being less affected by toxic substances. Studies, however, which have mainly been carried out on synthetic wastewater, cannot fully evaluate the actual ability of aerobic granules. Study on aerobic granular sludge was performed in sequencing batch reactors, using seeding sludge taken from anaerobic sludge and tapioca wastewater as a substrates. After 11 weeks of operation, the granules reached the stable diameter of 2- 3 mm at 3.7 kgCOD/m3.day organic loading rate. At high organic loads, in range of 1.6 - 5 kgCOD/m3.day, granules could treat effectively COD, N, P with performance of 93 – 97%; 65 – 79% and 80 – 95%, respectively.

Microbial diversity differences within aerobic granular sludge and activated sludge flocs

2012 ◽  
Vol 97 (16) ◽  
pp. 7447-7458 ◽  
Author(s):  
M-K H. Winkler ◽  
R. Kleerebezem ◽  
L. M. M. de Bruin ◽  
P. J. T. Verheijen ◽  
B. Abbas ◽  
...  
Keyword(s):  
Activated Sludge ◽  
Microbial Diversity ◽  
Granular Sludge ◽  
Aerobic Granular Sludge ◽  
Sludge Flocs

scholarly journals Removal of crystal violet from aqueous solutions using an aerobic granular sludge system

2021 ◽  
Vol 3 (1) ◽  
pp. 55-60
Author(s):  
Costel Bumbac ◽  
◽  
Elena Elisabeta Manea ◽  
Olga Tiron
Keyword(s):  
Activated Sludge ◽  
Respiration Rate ◽  
Crystal Violet ◽  
Treatment Cycle ◽  
Granular Sludge ◽  
Inhibitory Effect ◽  
Aerobic Granular Sludge ◽  
Specific Test ◽  
Conventional Activated Sludge ◽  
The Matrix

The paper presents a set of comparative tests to evaluate the inhibitory effect of crystal violet on the respiration rate of microorganisms in conventional activated sludge and aerobic granular sludge. The tests were performed in similar conditions with the only variable of the type of sludge tested. The results emphasized that the aerobic granular sludge is less susceptible to the toxicity induced by crystal violet. The concentration of crystal violet that inhibits by 50% (CE50) the respiration rate of sludge microorganisms was determined to be, for the specific test conditions, 22.39 mg/L for the conventional activated sludge and 33.88 mg/L for the aerobic granular sludge. The paper also assesses the biodegradability potential of crystal violet from aqueous solution, in the presence of sodium acetate as co-substrate in a lab-scale sequential biological reactor with aerobic granular sludge. The experiments showed that most of the crystal violet is being initially absorbed in the matrix of the granules during the first minutes and subsequently is being removed with efficiencies above 95% within a treatment cycle of 8 hours.

Sign in / Sign up

Export Citation Format

Share Document