Effect of Salinity on Cr(VI) Bioremediation by Algal-Bacterial Aerobic Granular Sludge Treating Synthetic Wastewater

Heavy metal-containing wastewater with high salinity challenges wastewater treatment plants (WWTPs) where the conventional activated sludge process is widely applied. Bioremediation has been proven to be an effective, economical, and eco-friendly technique to remove heavy metals from various wastewaters. The newly developed algal-bacterial aerobic granular sludge (AGS) has emerged as a promising biosorbent for treating wastewater containing heavy metals, especially Cr(VI). In this study, two identical cylindrical sequencing batch reactors (SBRs), i.e., R1 (Control) and R2 (with 1% additional salinity), were used to cultivate algal-bacterial AGS and then to evaluate the effect of salinity on the performance of the two SBRs. The results reflected that less filamentation and a rougher surface could be observed on algal-bacterial AGS when exposed to 1% salinity, which showed little influence on organics removal. However, the removals of total inorganic nitrogen (TIN) and total phosphorus (TP) were noticeably impacted at the 1% salinity condition, and were further decreased with the co-existence of 2 mg/L Cr(VI). The Cr(VI) removal efficiency, on the other hand, was 31–51% by R1 and 28–48% by R2, respectively, indicating that salinity exposure may slightly influence Cr(VI) bioremediation. In addition, salinity exposure stimulated more polysaccharides excretion from algal-bacterial AGS while Cr(VI) exposure promoted proteins excretion.

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Role of ammonia-oxidizing bacteria in micropollutant removal from wastewater with aerobic granular sludge

Water Science & Technology ◽

10.2166/wst.2015.514 ◽

2015 ◽

Vol 73 (3) ◽

pp. 564-575 ◽

Cited By ~ 22

Author(s):

Jonas Margot ◽

Samuel Lochmatter ◽

D. A. Barry ◽

Christof Holliger

Keyword(s):

Wastewater Treatment Plants ◽

Aerobic Condition ◽

Granular Sludge ◽

Synthetic Wastewater ◽

Aerobic Granular Sludge ◽

Batch Reactors ◽

Ammonia Oxidizing Bacteria ◽

Sequencing Batch Reactors ◽

Micropollutant Removal

Nitrifying wastewater treatment plants (WWTPs) are more efficient than non-nitrifying WWTPs to remove several micropollutants such as pharmaceuticals and pesticides. This may be related to the activity of nitrifying organisms, such as ammonia-oxidizing bacteria (AOBs), which could possibly co-metabolically oxidize micropollutants with their ammonia monooxygenase (AMO). The role of AOBs in micropollutant removal was investigated with aerobic granular sludge (AGS), a promising technology for municipal WWTPs. Two identical laboratory-scale AGS sequencing batch reactors (AGS-SBRs) were operated with or without nitrification (inhibition of AMOs) to assess their potential for micropollutant removal. Of the 36 micropollutants studied at 1 μg l−1 in synthetic wastewater, nine were over 80% removed, but 17 were eliminated by less than 20%. Five substances (bisphenol A, naproxen, irgarol, terbutryn and iohexol) were removed better in the reactor with nitrification, probably due to co-oxidation catalysed by AMOs. However, for the removal of all other micropollutants, AOBs did not seem to play a significant role. Many compounds were better removed in aerobic condition, suggesting that aerobic heterotrophic organisms were involved in the degradation. As the AGS-SBRs did not favour the growth of such organisms, their potential for micropollutant removal appeared to be lower than that of conventional nitrifying WWTPs.

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

Science and Technology Development Journal ◽

10.32508/stdj.v16i1.1386 ◽

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.

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Performance Evaluation of Continuous Flow Aerobic Granular Sludge Configurations

Revista de Chimie ◽

10.37358/rc.19.1.6900 ◽

2019 ◽

Vol 70 (1) ◽

pp. 283-285

Author(s):

Elena Elisabeta Manea ◽

Costel Bumbac

Keyword(s):

Wastewater Treatment ◽

Continuous Flow ◽

High Efficiency ◽

Wastewater Treatment Plants ◽

Granular Sludge ◽

Synthetic Wastewater ◽

Aerobic Granular Sludge ◽

Batch Reactors ◽

Nutrients Removal ◽

Flow Configurations

Increasing the efficiency and capacity of existing wastewater treatment plants can be carried out by using intensive biological processes. One of the currently studied biological solutions consists in using aerobic granular sludge in order to achieve both organics and nutrients removal simultaneously in one tank and with high efficiency. Aerobic granular sludge is currently used at full scale in sequential batch reactors, research for identifying the optimal solutions for continuous flow systems being carried out worldwide. The paper summarizes the results obtained for two continuous flow configurations with aerobic granular sludge, in terms of organics and nutrients removal for synthetic wastewater in laboratory conditions. Both experimental setups led to wastewater treatment efficiencies, with values ranging between 80 and 99% for COD, 85 and 99% for BOD5, 52 and 98% for NH4+ and 5 to 87% for TP.

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Parameter Optimisation of Aerobic Granular Sludge at High Temperature Using Response Surface Methodology

International Journal of Electrical and Computer Engineering (IJECE) ◽

10.11591/ijece.v7i3.pp1522-1529 ◽

2017 ◽

Vol 7 (3) ◽

pp. 1522 ◽

Cited By ~ 1

Author(s):

Syahira Ibrahim ◽

Norhaliza Abdul Wahab ◽

Aznah Nor Anuar ◽

Mustafa Bob

Keyword(s):

Response Surface Methodology ◽

Wastewater Treatment ◽

High Temperature ◽

Response Surface ◽

Treatment Plant ◽

Granular Sludge ◽

Synthetic Wastewater ◽

Aerobic Granular Sludge ◽

Batch Reactors ◽

Sequencing Batch Reactors

This paper proposes an improved optimisation of sequencing batch reactors (SBR) for aerobic granular sludge (AGS) at high temperature-low humidity for domestic wastewater treatment using response surface methodology (RSM). The main advantages of RSM are less number of experiment required and suitable for complex process. The sludge from a conventional activated sludge wastewater treatment plant and three sequencing batch reactors (SBRs) were fed with synthetic wastewater. The experiment were carried out at different high temperatures (30, 40 and 50°C) and the formation of AGS for simultaneous organics and nutrients removal were examined in 60 days. RSM is used to model and to optimize the biological parameters for chemical oxygen demand (COD) and total phosphorus removal in SBR system. The simulation results showed that at temperature of 45.33°C give the optimum condition for the total removal of COD and phosphorus, which correspond to performance index R<sup>2</sup> of 0.955 and 0.91, respectively.

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Monitoring the stability of aerobic granular sludge using fractal dimension analysis

Environmental Science Water Research & Technology ◽

10.1039/d1ew00015b ◽

2021 ◽

Author(s):

Juan Pablo Pavissich ◽

Nicolás Camus ◽

José Luis Campos ◽

Oscar Franchi ◽

Alba Pedrouso ◽

...

Keyword(s):

Fractal Dimension ◽

Granular Sludge ◽

Synthetic Wastewater ◽

Aerobic Granular Sludge ◽

Batch Reactors ◽

Sequencing Batch Reactors ◽

Dimension Analysis ◽

Fractal Dimension Analysis ◽

The Stability

Cyclic episodes of granules formation and disintegration took place in two lab-scale aerobic granular sludge sequencing batch reactors, one fed with synthetic wastewater (COD: 0.6 g/L and NH4+-N: 0.06 g/L)...

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