Rapid cultivation of aerobic granular sludge by xanthan gum in SBR reactors

Abstract This study focuses on the effect of xanthan gum on aerobic sludge granulation, through close monitoring of the physical and chemical changes of the aerobic granular sludge, and treatment performance. Two sequencing batch reactors (SBRs), R1 and R2, were seeded with activated sludge only (R1) and with a mixture of activated sludge and 40 mg/L of xanthan gum (R2). The results showed that granulation finished on the 20th day in R2, far faster than the granulation time of 30 days in R1. Meanwhile, there was a reliably higher sludge concentration, better settling properties and better particle mechanical strength in R2, and better removal performance of total nitrogen (TN) and chemical oxygen demand (COD). The results demonstrated that seeding xanthan gum enhanced the aerobic sludge granulation in the SBR. Maybe its anionic and hydrophilic surface characteristics facilitate interactions with cations and other polysaccharides, inducing stronger gelation, which promoted the formation of particles or increased the internal relationship between particles, thereby increasing the cohesion within the sludge, so that the granular sludge was not easily broken.

Download Full-text

Dynamic Modelling of Aerobic Granular Sludge Artificial Neural Networks

International Journal of Electrical and Computer Engineering (IJECE) ◽

10.11591/ijece.v7i3.pp1568-1573 ◽

2017 ◽

Vol 7 (3) ◽

pp. 1568

Author(s):

Nurazizah Mahmod ◽

Norhaliza Abdul Wahab

Keyword(s):

Neural Network ◽

Batch Reactor ◽

Dynamic Modelling ◽

Oxygen Demand ◽

Granular Sludge ◽

Aerobic Granular Sludge ◽

Batch Reactors ◽

Neural Network Approach ◽

Dynamic Neural Network ◽

Promising Development

Aerobic Granular Sludge (AGS) technology is a promising development in the field of aerobic wastewater treatment system. Aerobic granulation usually happened in sequencing batch reactors (SBRs) system. Most available models for the system are structurally complex with the nonlinearity and uncertainty of the system makes it hard to predict. A reliable model of AGS is essential in order to provide a tool for predicting its performance. This paper proposes a dynamic neural network approach to predict the dynamic behavior of aerobic granular sludge SBRs. The developed model will be applied to predict the performance of AGS in terms of the removal of Chemical Oxygen Demand (COD). The simulation uses the experimental data obtained from the sequencing batch reactor under three different conditions of temperature (30˚C, 40˚C and 50˚C). The overall results indicated that the dynamic of aerobic granular sludge SBR can be successfully estimated using dynamic neural network model, particularly at high temperature.

Download Full-text

Comparative performance of activated sludge and aerobic granular sludge sequencing batch reactors for removing metalloid SeIV/VI oxyanions

Journal of Hazardous Materials Letters ◽

10.1016/j.hazl.2021.100040 ◽

2021 ◽

Vol 2 ◽

pp. 100040

Author(s):

M. Sarvajith ◽

Y.V. Nancharaiah

Keyword(s):

Activated Sludge ◽

Granular Sludge ◽

Aerobic Granular Sludge ◽

Batch Reactors ◽

Sequencing Batch Reactors ◽

Comparative Performance

Download Full-text

Analysis for the Impact of Loadings in the Formation Process of Aerobic Granular Sludge

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.518-523.2340 ◽

2012 ◽

Vol 518-523 ◽

pp. 2340-2343

Author(s):

Ting Lin ◽

Xin Gang Wang ◽

Yu Bin Tang ◽

Fang Yan Chen

Keyword(s):

Activated Sludge ◽

Formation Process ◽

Granular Sludge ◽

The Self ◽

Aerobic Granular Sludge ◽

Batch Reactors ◽

Sequencing Batch Reactors ◽

Removal Rates ◽

High Sedimentation ◽

The Impact

The aerobic granular sludge was cultivated in the self-designed sequencing batch reactors (SBR) using ordinary flocculent activated sludge as seeding sludge. In this experiment the effect of different load on the formation of aerobic granular sludge is studied. The formation process of aerobic granular sludge and the capacity of denitrification and phosphorus performance are discussed and characterized. It shows that higher sludge loading is beneficial to the formation of aerobic granular sludge, and mature aerobic granular sludge has high sedimentation speed and the very good decontamination ability. The removal rates of COD, NH4+Subscript text-N and TP are 97%, 85% and 95%.

Download Full-text

Aerobic granular sludge technology: an alternative to activated sludge?

Water Science & Technology ◽

10.2166/wst.2004.0790 ◽

2004 ◽

Vol 49 (11-12) ◽

pp. 1-7 ◽

Cited By ~ 131

Author(s):

L.M.M. de Bruin ◽

M.K. de Kreuk ◽

H.F.R. van der Roest ◽

C. Uijterlinde ◽

M.C.M. van Loosdrecht

Keyword(s):

The Netherlands ◽

Activated Sludge ◽

Sewage Treatment ◽

Treatment Plant ◽

Granular Sludge ◽

Primary Treatment ◽

Aerobic Granular Sludge ◽

Batch Reactors ◽

Sequencing Batch Reactors ◽

Effluent Standards

Laboratory experiments have shown that it is possible to cultivate aerobic granular sludge in sequencing batch reactors. In order to direct future research needs and the critical points for successful implementation at large scale, a full detailed design of a potential application was made. The design was based on the laboratory results, and two variants of a full-scale sewage treatment plant based on Granular sludge Sequencing Batch Reactors (GSBRs) were evaluated. As a reference a conventional treatment plant based on activated sludge technology was designed for the same case. Based on total annual costs both GSBR variants proved to be more attractive than the reference alternative (7-17% lower costs). From a sensitivity analysis it appeared that the GSBR technology was less sensitive to the land price and more sensitive to a rain weather flow (RWF). This means that the GSBR technology becomes more attractive at lower permissible RWF/DWF ratios and higher land prices. The footprint of the GSBR variants was only 25% compared to the reference. However, the GSBR with primary treatment only cannot meet the present effluent standards for municipal wastewater in The Netherlands, mainly because of a too high suspended solids concentration in the effluent. A growing number of sewage treatment plants in the Netherlands are going to be faced with more stringent effluent standards. In general, activated sludge plants will have to be extended with a post treatment step (e.g. sand filtration) or be transformed into Membrane Bioreactors. In this case a GSBR variant with primary treatment as well as post treatment can be an attractive alternative.

Download Full-text

Simulation of Aerobic Granular Sludge Process Efficiency

Revista de Chimie ◽

10.37358/rc.17.8.5752 ◽

2017 ◽

Vol 68 (8) ◽

pp. 1723-1725

Author(s):

Elena Elisabeta Manea ◽

Costel Bumbac ◽

Olga Tiron ◽

Razvan Laurentiu Dinu ◽

Valeriu Robert Badescu

Keyword(s):

Wastewater Treatment ◽

Activated Sludge ◽

Batch Reactor ◽

Granular Sludge ◽

Process Efficiency ◽

Aerobic Granular Sludge ◽

Organic Load ◽

Batch Reactors ◽

Conventional Activated Sludge ◽

Pollutants Removal

Using aerobic granular sludge for wastewater treatment has multiple advantages compared to conventional activated sludge systems, most important being the ability of simultaneous removal of the pollutants responsible for eutrophication: organic load, compounds of nitrogen (NH4+; NO3-) and phosphorus (PO43-). The advantages are currently exploited for developing the next generation of wastewater treatment systems while the identified limitations are approached by experimental and theoretical researches worldwide. The aim of the study consists in evaluating the possibility of predicting the system�s response to different changes in the influent wastewater loadings. The paper presents simulations results backed up by experimental data for pollutants removal efficiencies evaluation for a sequential batch reactor (SBR) with aerobic granular sludge. The mathematical model is based on the activated sludge model no. 3, which was updated by considering the simultaneous biological nitrification (NH4+NO3) and denitrification (NO3-N2) processes, thus complying with the biochemical reactions occurring in aerobic granular sludge sequential batch reactors. The model developed was validated by the experimental results obtained on a laboratory scale SBR monitored for over a month.

Download Full-text

Support Vector Regression Modelling of an Aerobic Granular Sludge in Sequential Batch Reactor

Membranes ◽

10.3390/membranes11080554 ◽

2021 ◽

Vol 11 (8) ◽

pp. 554

Author(s):

Nur Sakinah Ahmad Yasmin ◽

Norhaliza Abdul Wahab ◽

Fatimah Sham Ismail ◽

Mu’azu Jibrin Musa ◽

Mohd Hakim Ab Halim ◽

...

Keyword(s):

Support Vector Regression ◽

Batch Reactor ◽

Oxygen Demand ◽

Granular Sludge ◽

Aerobic Granular Sludge ◽

Support Vector ◽

Batch Reactors ◽

Grid Search Method ◽

Internal Interaction ◽

Kernel Parameters

Support vector regression (SVR) models have been designed to predict the concentration of chemical oxygen demand in sequential batch reactors under high temperatures. The complex internal interaction between the sludge characteristics and their influent were used to develop the models. The prediction becomes harder when dealing with a limited dataset due to the limitation of the experimental works. A radial basis function algorithm with selected kernel parameters of cost and gamma was used to developed SVR models. The kernel parameters were selected by using a grid search method and were further optimized by using particle swarm optimization and genetic algorithm. The SVR models were then compared with an artificial neural network. The prediction results R2 were within >90% for all predicted concentration of COD. The results showed the potential of SVR for simulating the complex aerobic granulation process and providing an excellent tool to help predict the behaviour in aerobic granular reactors of wastewater treatment.

Download Full-text

Deemulsification of Water-in-Oil Emulsion with Sludges

Water Quality Research Journal ◽

10.2166/wqrj.1987.034 ◽

1987 ◽

Vol 22 (3) ◽

pp. 437-443 ◽

Cited By ~ 5

Author(s):

N. Kosaric ◽

Z. Duvnjak

Keyword(s):

Activated Sludge ◽

Room Temperature ◽

Petroleum Refinery ◽

Treatment Plant ◽

Granular Sludge ◽

Activated Sludge Process ◽

Sludge Treatment ◽

Oil Emulsion ◽

Water In Oil Emulsion ◽

Aerobic Sludge

Abstract Aerobic sludge from a municipal activated sludge treatment plant, sludge from a conventional municipal anaerobic digester, aerobic sludge from an activated sludge process of a petroleum refinery, and granular sludge from an upflow sludge blanket reactor (USBR) were tested in the deemulsification of a water-in-oil emulsion. All sludges except the last one, showed a good deemulsification capability and could he used for a partial deemulsification of such emulsions. The rate and degree of the deemulsifications increased with an increase in sludge concentrations. The deemulsifications were faster at 85°C and required smaller amounts of sludge than in the case of the deemulsifications at room temperature. An extended stirring (up to a certain limit) in the course of the dispersion of sludge emulsion helped the deemulsification. Too vigorous agitation had an adverse effect. The deemulsification effect of sludge became less visible with an increase in the dilution of emulsion which caused an increase in its spontaneous deemulsification.

Download Full-text

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

Applied Microbiology and Biotechnology ◽

10.1007/s00253-021-11443-3 ◽

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

Download Full-text