scholarly journals DEVELOPMENT OF AEROBIC GRANULES IN SEQUENCING BATCH REACTOR SYSTEM FOR TREATING HIGH TEMPERATURE DOMESTIC WASTEWATER

2019 ◽  
Vol 81 (3) ◽  
Author(s):  
Mohd Hakim Ab Halim ◽  
Aznah Nor Anuar ◽  
Shreeshivadasan Chelliapan ◽  
Norhaliza Abdul Wahab ◽  
Hazlami Fikri Basri ◽  
...  
Keyword(s):  
High Temperature ◽  
Sequencing Batch Reactor ◽  
Batch Reactor ◽  
Oxygen Demand ◽  
Biomass Concentration ◽  
Domestic Wastewater ◽  
Granular Sludge ◽  
Aerobic Granular Sludge ◽  
Organic Loading Rate ◽  
Hot Climate

The application of aerobic granular sludge (AGS) in treating real domestic wastewater at high temperature is still lacking. In this study, the microstructure and morphology of the granules, as well as bioreactor performance, were investigated during the treatment of real domestic wastewater at high temperature (50 °C). The experiment was executed in a sequencing batch reactor (SBR) with a complete cycle time of 3 hours for the treatment of low-strength domestic wastewater at an organic loading rate (OLR) of 0.6 kg COD m−3 d−1. Stable mature granules with average diameters between 2.0 and 5.0 mm, and good biomass concentration of 5.8 g L−1 were observed in the bioreactor. AGS achieved promising results in the treatment of domestic wastewater with good removal rates of 84.4 %, 99.6 % and 81.7 % for chemical oxygen demand (COD), ammoniacal nitrogen (NH3−N), and total phosphorus (TP), respectively. The study demonstrated the formation capabilities of AGS in a single, high and slender column type-bioreactor at high temperature which is suitable to be applied in hot climate condition areas especially countries with tropical and desert-like climates.

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.

Cultivation of Aerobic Granular Sludge under Selective Pressure in a Sequencing Batch Reactor

2011 ◽  
Vol 255-260 ◽  
pp. 3037-3041 ◽  
Author(s):  
Kui Zu Su ◽  
Chang Wang ◽  
Hui Fang
Keyword(s):  
Suspended Solids ◽  
Sequencing Batch Reactor ◽  
Settling Velocity ◽  
Selective Pressure ◽  
Batch Reactor ◽  
Oxygen Demand ◽  
Granular Sludge ◽  
Volume Index ◽  
Aerobic Granular Sludge ◽  
Granulation Process

Aerobic granules were cultivated in the sequencing batch reactor at 15-25°C, pH 7.0 ± 0.1. Settling time decreased from 5 minutes to 1 minute gradually. As increasing the chemical oxygen demand (COD) and NH3-N in influent, COD removal efficiency and mixed liquid suspended solids of the reactor increased. Sludge volume index decreased continuously for a few days and then stabilized at 22 ml g-1. Selective pressure induced by settling velocity was proved to play a crucial role in activated sludge granulation. Based on the continuously measured data, the granulation process was divided into three phases, granules namely initiating, developing and maturating.

Optimization of operation conditions for preventing sludge bulking and enhancing the stability of aerobic granular sludge in sequencing batch reactors

2014 ◽  
Vol 70 (9) ◽  
pp. 1519-1525 ◽  
Author(s):  
Jun Zhou ◽  
Hongyu Wang ◽  
Kai Yang ◽  
Fang Ma ◽  
Bin Lv
Keyword(s):  
Batch Reactor ◽  
Biomass Concentration ◽  
Granular Sludge ◽  
Synthetic Wastewater ◽  
Aerobic Granular Sludge ◽  
Organic Loading Rate ◽  
Filamentous Bacteria ◽  
Operation Conditions ◽  
Sludge Bulking ◽  
The Stability

Sludge bulking caused by loss of stability is a major problem in aerobic granular sludge systems. This study investigated the feasibility of preventing sludge bulking and enhancing the stability of aerobic granular sludge in a sequencing batch reactor by optimizing operation conditions. Five operation parameters have been studied with the aim to understand their impact on sludge bulking. Increasing dissolved oxygen (DO) by raising aeration rates contributed to granule stability due to the competition advantage of non-filamentous bacteria and permeation of oxygen at high DO concentration. The ratio of polysaccharides to proteins was observed to increase as the hydraulic shear force increased. When provided with high/low organic loading rate (OLR) alternately, large and fluffy granules disintegrated, while denser round-shape granules formed. An increase of biomass concentration followed a decrease at the beginning, and stability of granules was improved. This indicated that aerobic granular sludge had the resistance of OLR. Synthetic wastewater combined highly and slowly biodegradable substrates, creating a high gradient, which inhibited the growth of filamentous bacteria and prevented granular sludge bulking. A lower chemical oxygen demand/N favored the hydrophobicity of granular sludge, which promoted with granule stability because of the lower diffusion rate of ammonia. The influence of temperature indicated a relatively low temperature was more suitable.

scholarly journals Performance of Aerobic Granular Sludge for Domestic Wastewater Treatment

2019 ◽  
Vol 8 (12) ◽  
pp. 3851-3854
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Batch Reactor ◽  
Biomass Concentration ◽  
Domestic Wastewater ◽  
Granular Sludge ◽  
Volume Index ◽  
Aerobic Granular Sludge ◽  
Domestic Wastewater Treatment ◽  
Low Strength

Aerobic granular sludge can be used to treat various types of wastewater, such as industrial, municipal and domestic wastewater. This study investigated the treatment of low-strength domestic wastewater while simultaneously developed aerobic granular sludge in a sequencing batch reactor (SBR). Activated sludge was used as the seeding for granulation. The results indicated good COD and ammoniacal nitrogen removal at 72% and 73%, respectively. Aerobic granular sludge was successfully developed with low sludge volume index (SVI30) of 29 mL/g, which demonstrated an excellent settling property of aerobic granular sludge. Biomass concentration increased significantly compared to the seed sludge, indicating high biomass density in the SBR system. Settling velocity of aerobic granular sludge was significantly higher compared to the conventional activated sludge. This study showed the feasibility of aerobic granular sludge to be developed using low-strength domestic wastewater. Moreover, this study demonstrated the long-term application of aerobic granular sludge in domestic wastewater treatment.

scholarly journals Anaerobic hydrolysis of complex substrates in full-scale aerobic granular sludge: enzymatic activity determined in different sludge fractions

2021 ◽  
Author(s):  
Sara Toja Ortega ◽  
Mario Pronk ◽  
Merle K. de Kreuk
Keyword(s):  
Hydrolytic Enzymes ◽  
Oxygen Demand ◽  
Domestic Wastewater ◽  
Granular Sludge ◽  
Hydrolytic Activity ◽  
Full Scale ◽  
Aerobic Granular Sludge ◽  
Bulk Liquid ◽  
Granule Formation ◽  
Hydrolysis Of

Abstract Complex substrates, like proteins, carbohydrates, and lipids, are major components of domestic wastewater, and yet their degradation in biofilm-based wastewater treatment technologies, such as aerobic granular sludge (AGS), is not well understood. Hydrolysis is considered the rate-limiting step in the bioconversion of complex substrates, and as such, it will impact the utilization of a large wastewater COD (chemical oxygen demand) fraction by the biofilms or granules. To study the hydrolysis of complex substrates within these types of biomass, this paper investigates the anaerobic activity of major hydrolytic enzymes in the different sludge fractions of a full-scale AGS reactor. Chromogenic substrates were used under fully mixed anaerobic conditions to determine lipase, protease, α-glucosidase, and β-glucosidase activities in large granules (>1 mm in diameter), small granules (0.2–1 mm), flocculent sludge (0.045–0.2 mm), and bulk liquid. Furthermore, composition and hydrolytic activity of influent wastewater samples were determined. Our results showed an overcapacity of the sludge to hydrolyze wastewater soluble and colloidal polymeric substrates. The highest specific hydrolytic activity was associated with the flocculent sludge fraction (1.5–7.5 times that of large and smaller granules), in agreement with its large available surface area. However, the biomass in the full-scale reactor consisted of 84% large granules, making the large granules account for 55–68% of the total hydrolytic activity potential in the reactor. These observations shine a new light on the contribution of large granules to the conversion of polymeric COD and suggest that large granules can hydrolyze a significant amount of this influent fraction. The anaerobic removal of polymeric soluble and colloidal substrates could clarify the stable granule formation that is observed in full-scale installations, even when those are fed with complex wastewaters. Key points • Large and small granules contain >70% of the hydrolysis potential in an AGS reactor. • Flocculent sludge has high hydrolytic activity but constitutes <10% VS in AGS. • AGS has an overcapacity to hydrolyze complex substrates in domestic wastewater. Graphical abstract

Start-up of an aerobic granular sequencing batch reactor for the treatment of winery wastewater

2009 ◽  
Vol 60 (4) ◽  
pp. 1049-1054 ◽  
Author(s):  
S. López–Palau ◽  
J. Dosta ◽  
J. Mata-Álvarez
Keyword(s):  
Organic Matter ◽  
Sequencing Batch Reactor ◽  
Batch Reactor ◽  
Particle Diameter ◽  
Granular Sludge ◽  
Average Density ◽  
Aerobic Granular Sludge ◽  
Organic Load ◽  
Winery Wastewater ◽  
Start Up

Aerobic granular sludge was cultivated in a sequencing batch reactor (SBR) in order to remove the organic matter present in winery wastewater. The formation of granules was performed using a synthetic substrate. The selection parameter was the settling time, as well as the alternation of feast-famine periods, the air velocity and the height/diameter ratio of the reactor. After 10 days of operation under these conditions, the first aggregates could be observed. Filamentous bacteria were still present in the reactor but they disappeared progressively. During the start-up, COD loading was increased from 2.7 to 22.5 kg COD/(m3 day) in order to obtain a feast period between 30 and 60 minutes. At this point, granules were quite round, with a particle diameter between 3.0 and 4.0 mm and an average density of 6 g L−1. After 120 days of operation, synthetic media was replaced by real winery wastewater, with a COD loading of 6 kg COD/(m3 day). The decrease of the organic load implied a reduction of the aggregate diameter and a density increase up to 13.2 g L−1. The effluent was free of organic matter and the solids concentration in the reactor reached 6 g VSS L−1.

Adsorption of Cd(ii) from aqueous solution by biogenic selenium nanoparticles

RSC Advances ◽  
2016 ◽  
Vol 6 (18) ◽  
pp. 15201-15209 ◽  
Author(s):  
Fanghui Yuan ◽  
Chao Song ◽  
Xuefei Sun ◽  
Linrui Tan ◽  
Yunkun Wang ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Sequencing Batch Reactor ◽  
High Efficiency ◽  
Batch Reactor ◽  
Granular Sludge ◽  
Selenium Nanoparticles ◽  
Aerobic Granular Sludge ◽  
Biogenic Selenium Nanoparticles

BioSeNPs, which were produced by aerobic granular sludge in a sequencing batch reactor, could be used to remove cadmium from aqueous solution with high efficiency.

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