Effects of CuO NPs on the pollutant removal, EPS and microbial community of aerobic granular sludge

With the increasing use of cupric oxide nanoparticles (CuO NPs), its potential environmental toxicity has been concerned nowadays. Aerobic granular sludge (AGS) is a special collection of microorganisms. This research studied under long exposure to the concentration of 5, 10 and 20 mg/L of CuO NPs, pollutants removal efficiency of AGS, extracellular polymers (EPS) and microbial communities in aerobic/anaerobic/anoxic (A/O/A) sequencing batch reactors (SBRs). The results showed that COD removal rates was stable, and the removal efficiencies of TN decreased because of the high concentration CuO NPs. On the 45th day, the TP removal efficiency of the reactor with CuO NPs concentration of 10 mg/L and 20 mg/L decreased to 55.83% and 43.72%, respectively. The denitrifying phosphorus removal-aerobic granular sludge (DPR-AGS) had certain resistance to the short-term impact of CuO NPs, and the phosphorus removal ability decreased at the late stage of the impact test. Besides, CuO NPs decreased the stability of DPR-AGS. High-throughput sequencing showed that CuO NPs decreased microbial diversity of DPR-AGS.

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Response of Aerobic Granular Sludge to the Long-Term Presence of CuO NPs in A/O/A SBRs: Nitrogen and Phosphorus Removal, Enzymatic Activity, and the Microbial Community

Environmental Science & Technology ◽

10.1021/acs.est.7b02768 ◽

2017 ◽

Vol 51 (18) ◽

pp. 10503-10510 ◽

Cited By ~ 19

Author(s):

Xiao-ying Zheng ◽

Dan Lu ◽

Wei Chen ◽

Ya-jie Gao ◽

Gan Zhou ◽

...

Keyword(s):

Microbial Community ◽

Enzymatic Activity ◽

Phosphorus Removal ◽

Granular Sludge ◽

Aerobic Granular Sludge ◽

Nitrogen And Phosphorus ◽

Nitrogen And Phosphorus Removal ◽

Cuo Nps

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Impacts of variable pH on stability and nutrient removal efficiency of aerobic granular sludge

Water Science & Technology ◽

10.2166/wst.2015.460 ◽

2015 ◽

Vol 73 (1) ◽

pp. 60-68 ◽

Cited By ~ 4

Author(s):

Monireh Lashkarizadeh ◽

Giulio Munz ◽

Jan A. Oleszkiewicz

Keyword(s):

Removal Efficiency ◽

Nutrient Removal ◽

Phosphorus Removal ◽

Granular Sludge ◽

Aerobic Granular Sludge ◽

Acidic Ph ◽

Alkaline Ph ◽

Nitrogen And Phosphorus ◽

Nitrogen And Phosphorus Removal ◽

Ph Shock

The impact of pH variation on aerobic granular sludge stability and performance was investigated. A 9-day alkaline (pH = 9) and acidic (pH = 6) pH shocks were imposed on mature granules with simultaneous chemical oxygen demand (COD), nitrogen and phosphorus removal. The imposed alkaline pH shock (pH 9) reduced nitrogen and phosphorus removal efficiency from 88% and 98% to 66% and 50%, respectively, with no further recovery. However, acidic pH shock (pH 6) did not have a major impact on nutrient removal and the removal efficiencies recovered to their initial values after 3 days of operation under the new pH condition. Operating the reactors under alkaline pH induced granules breakage and resulted in an increased solids concentration in the effluent and a significant decrease in the size of the bio-particles, while acidic pH did not have significant impacts on granules stability. Changes in chemical structure and composition of extracellular polymeric substances (EPS) matrix were suggested as the main factors inducing granules instability under high pH.

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Research on COD Removal and SOUR of Aerobic Granule with Intermittent Aeration in Continuous Flow System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.518-523.478 ◽

2012 ◽

Vol 518-523 ◽

pp. 478-484 ◽

Cited By ~ 1

Author(s):

Feng Deng ◽

Rui Zhang

Keyword(s):

Removal Efficiency ◽

Continuous Flow ◽

Flow Reactor ◽

Operation Mode ◽

Granular Sludge ◽

Cod Removal ◽

Aerobic Granular Sludge ◽

Intermittent Aeration ◽

Cod Removal Efficiency ◽

The Impact

The impact of intermittent aeration on aerobic granular sludge in a continuous flow reactor was studied. Nine intermittent aeration modes were set up to investigate the change of DO, pH, COD removal efficiency and SOUR. The results showed DO and pH had different change tendencies. The 3-1 mode was the optimal mode under these experiment conditions. In aerating stage, the highest COD removal efficiency could achieve 96.32%. Stopping aeration for one hour, COD removal efficiency could still reach at 90.20%. This operation mode could save about 25% energy consumption theoretically. The comparison of SOUR between continuous aeration and 4-2 mode showed that the intermittent aeration had little effect on granular sludge activity. The theory of stress & damage and unbalanced growth could explain this appearance.

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Start-up of an aerobic granular sludge system from stored granules: Evaluating the impact of storage period on biomass activity and stability and the effect of temperature on nitrification and phosphorus removal rates

Journal of Environmental Management ◽

10.1016/j.jenvman.2021.113200 ◽

2021 ◽

Vol 296 ◽

pp. 113200

Author(s):

K.L.S. Duarte ◽

R.M. Castellanos ◽

R.C. Costa ◽

C.F. Mahler ◽

J.P. Bassin

Keyword(s):

Phosphorus Removal ◽

Storage Period ◽

Granular Sludge ◽

Aerobic Granular Sludge ◽

Effect Of Temperature ◽

Removal Rates ◽

Start Up ◽

Biomass Activity ◽

The Impact

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Stability of aerobic granular sludge under low energy consumption: Optimization of granular size distribution by a novel internal component

Environmental Science Water Research & Technology ◽

10.1039/d1ew00060h ◽

2021 ◽

Author(s):

Runjuan Cao ◽

Yatong Ji ◽

Taixing Han ◽

Jingsong Deng ◽

Liang Zhu ◽

...

Keyword(s):

Energy Consumption ◽

Granular Sludge ◽

Pollutant Removal ◽

Low Energy ◽

Aerobic Granular Sludge ◽

Mesh Screen ◽

Energy Consumption Optimization ◽

Low Energy Consumption ◽

Internal Component ◽

The Stability

To enhance the stability and pollutant removal performance of an aerobic granular sludge (AGS), four groups of AGS reactors with different pore sizes of mesh screen (R1 is control reactor,...

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Improving the Treatment Performance of Low Impact Development Practices—Comparison of Sand and Bioretention Soil Mixtures Using Column Experiments

Water ◽

10.3390/w13091210 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1210

Author(s):

Abtin Shahrokh Hamedani ◽

Arianne Bazilio ◽

Hanieh Soleimanifar ◽

Heather Shipley ◽

Marcio Giacomoni

Keyword(s):

Phosphorus Removal ◽

Low Impact Development ◽

Pollutant Removal ◽

Control Measures ◽

Column Experiments ◽

Removal Rates ◽

Treatment Performance ◽

Soil Mixtures ◽

Limestone Sand ◽

The Impact

Low impact development (LID) practices, such as bioretention and sand filter basins, are stormwater control measures designed to mitigate the adverse impacts of urbanization on stormwater. LID treatment performance is highly dependent on the media characteristics. The literature suggests that bioretention media often leach nutrients in the stormwater effluent. The objective of this study was to analyze the treatment performance of different sand and bioretention soil mixtures. Specifically, this investigation aimed to answer whether the use of limestone and recycled glass could improve the treatment performance of bioretention systems. Column experiments were designed to assess (1) the removal efficiencies of different sand and bioretention soil mixtures and (2) the impact of plant uptake on removal rates. Enhanced pollutant removal was observed for the custom blends with addition of limestone sand, indicating mean dissolved and total phosphorus removal of 44.5% and 32.6% respectively, while the conventional bioretention soil mixtures leached phosphorus. Moreover, improved treatment of dissolved and total copper was achieved with mean removal rates of 70.7% and 93.4%, respectively. The results suggest that the nutrient effluent concentration decreased with the addition of plants, with mean phosphorus removal of 72.4%, and mean nitrogen removal of 22% for the limestone blend.

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