Combining continuous flow aerobic granulation using an external selector and carbon-efficient nutrient removal with AvN control in a full-scale simultaneous nitrification-denitrification process

The biodegradation of particulate substrates starts by a hydrolytic stage. Hydrolysis is a slow reaction and usually becomes the rate limiting step of the organic substrates biodegradation. The objective of this work was to evaluate a novel hydrolysis concept based on a modification of the activated sludge model (ASM2d) and to compare it with the original ASM2d model. The hydrolysis concept was developed in order to accurately predict the use of internal carbon sources in enhanced biological nutrient removal (BNR) processes at a full scale facility located in northern Poland. Both hydrolysis concepts were compared based on the accuracy of their predictions for the main processes taking place at a full-scale facility. From the comparison, it was observed that the modified ASM2d model presented similar predictions to those of the original ASM2d model on the behavior of chemical oxygen demand (COD), NH4-N, NO3-N, and PO4-P. However, the modified model proposed in this work yield better predictions of the oxygen uptake rate (OUR) (up to 5.6 and 5.7%) as well as in the phosphate release and uptake rates.

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Demonstration of enhanced nutrient removal at two full-scale SBR plants

Water Science & Technology ◽

10.2166/wst.2004.0623 ◽

2004 ◽

Vol 50 (10) ◽

pp. 115-120 ◽

Cited By ~ 5

Author(s):

M. Peters ◽

M. Newland ◽

T. Seviour ◽

T. Broom ◽

T. Bridle

Keyword(s):

Nutrient Removal ◽

Full Scale ◽

Biological Nutrient Removal ◽

Batch Reactors ◽

Simultaneous Nitrification And Denitrification ◽

Sequencing Batch Reactors ◽

Operational Control ◽

The World ◽

High Level ◽

Operational Data

The efficacy of sequencing batch reactors (SBRs) to provide high levels of biological nutrient removal has been extensively demonstrated around the world. Environmental Solutions International (ESI) has now constructed over 20 full-scale SBR plants and has confirmed that nutrient removal is enhanced via the process of simultaneous nitrification and denitrification. Over 18 months of operational data from two plants, operating in distinctly different catchments, processing an average of between 2,000 and 2,500 m3/d of wastewater, has clearly shown the efficacy and robustness of the ESI SBR-BNR process. Median effluent total nitrogen and total phosphorus values of 3 mg/L and <0.6 mg/L, respectively, were demonstrated over the 18-month period. This high level of nutrient removal is attributed to the design of the bio-selector which maximises carbon storage for the subsequent denitrification reactions, the effective aeration control which ensures no over-aeration during the air-on cycle as well as the level of operational control provided at these two plants.

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Development of a Continuous Flow Process for a Matteson Reaction: From Lab Scale to Full-Scale Production of a Pharmaceutical Intermediate

Organic Process Research & Development ◽

10.1021/acs.oprd.8b00340 ◽

2019 ◽

Vol 23 (5) ◽

pp. 1069-1077 ◽

Cited By ~ 8

Author(s):

Clemens Stueckler ◽

Peter Hermsen ◽

Bas Ritzen ◽

Maria Vasiloiu ◽

Peter Poechlauer ◽

...

Keyword(s):

Continuous Flow ◽

Full Scale ◽

Scale Production ◽

Flow Process ◽

Continuous Flow Process

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The Microbial Database for Danish wastewater treatment plants with nutrient removal (MiDas-DK) – a tool for understanding activated sludge population dynamics and community stability

Water Science & Technology ◽

10.2166/wst.2013.151 ◽

2013 ◽

Vol 67 (11) ◽

pp. 2519-2526 ◽

Cited By ~ 18

Author(s):

A. T. Mielczarek ◽

A. M. Saunders ◽

P. Larsen ◽

M. Albertsen ◽

M. Stevenson ◽

...

Keyword(s):

Wastewater Treatment ◽

Activated Sludge ◽

Nutrient Removal ◽

Wastewater Treatment Plants ◽

Amplicon Sequencing ◽

Temporal Variations ◽

Full Scale ◽

16S Rrna Amplicon Sequencing ◽

Specific Factors ◽

Operational Data

Since 2006 more than 50 Danish full-scale wastewater treatment plants with nutrient removal have been investigated in a project called ‘The Microbial Database for Danish Activated Sludge Wastewater Treatment Plants with Nutrient Removal (MiDas-DK)’. Comprehensive sets of samples have been collected, analyzed and associated with extensive operational data from the plants. The community composition was analyzed by quantitative fluorescence in situ hybridization (FISH) supported by 16S rRNA amplicon sequencing and deep metagenomics. MiDas-DK has been a powerful tool to study the complex activated sludge ecosystems, and, besides many scientific articles on fundamental issues on mixed communities encompassing nitrifiers, denitrifiers, bacteria involved in P-removal, hydrolysis, fermentation, and foaming, the project has provided results that can be used to optimize the operation of full-scale plants and carry out trouble-shooting. A core microbial community has been defined comprising the majority of microorganisms present in the plants. Time series have been established, providing an overview of temporal variations in the different plants. Interestingly, although most microorganisms were present in all plants, there seemed to be plant-specific factors that controlled the population composition thereby keeping it unique in each plant over time. Statistical analyses of FISH and operational data revealed some correlations, but less than expected. MiDas-DK (www.midasdk.dk) will continue over the next years and we hope the approach can inspire others to make similar projects in other parts of the world to get a more comprehensive understanding of microbial communities in wastewater engineering.

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The Sensitivity of a Specific Denitrification Rate under the Dissolved Oxygen Pressure

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17249366 ◽

2020 ◽

Vol 17 (24) ◽

pp. 9366

Author(s):

Massimo Raboni ◽

Paolo Viotti ◽

Elena Cristina Rada ◽

Fabio Conti ◽

Maria Rosaria Boni

Keyword(s):

Sensitivity Analysis ◽

Dissolved Oxygen ◽

Scientific Literature ◽

Full Scale ◽

Denitrification Rate ◽

The Third ◽

Small Influence ◽

Denitrification Reactor ◽

Activated Sludge Processes ◽

Denitrification Process

The biological denitrification process is extensively discussed in scientific literature. The process requires anoxic conditions, but the influence of residual dissolved oxygen (DO) on the efficiency is not yet adequately documented. The present research aims to fill this gap by highlighting the effects of DO on the specific denitrification rate (SDNR) and consequently on the efficiency of the process. SDNR at a temperature of 20 °C (SDNR20°C) is the parameter normally used for the sizing of the denitrification reactor in biological-activated sludge processes. A sensitivity analysis of SNDR20°C to DO variations is developed. For this purpose, two of the main empirical models illustrated in the scientific literature are taken into consideration, with the addition of a deterministic third model proposed by the authors and validated by recent experimentations on several full-scale plants. In the first two models, SDNR20°C is expressed as a function of the only variable food:microrganism ratio in denitrification (F:MDEN), while in the third one, the dependence on DO is made explicit. The sensitivity analysis highlights all the significant dependence of SDNR20°C on DO characterized by a logarithmic decrease with a very pronounced gradient in correspondence with low DO concentrations. Moreover, the analysis demonstrates the relatively small influence of F:MDEN on the SDNR20°C and on the correlation between SDNR20°C and DO. The results confirm the great importance of minimizing DO and limiting, as much as possible, the transport of oxygen in the denitrification reactor through the incoming flows and mainly the mixed liquor recycle. Solutions to achieve this result in full-scale plants are reported.

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Aggregate size-dependence of bacterial community separation in a full-scale membrane bioreactor plant

FEMS Microbiology Ecology ◽

10.1093/femsec/fiaa060 ◽

2020 ◽

Vol 96 (5) ◽

Author(s):

Shaoqing Zhang ◽

Bing Li ◽

Zhong Yu ◽

Fangang Meng

Keyword(s):

Bacterial Community ◽

Activated Sludge ◽

Nutrient Removal ◽

Species Interactions ◽

Membrane Bioreactor ◽

Size Dependence ◽

Full Scale ◽

Water Separation ◽

Significant Difference ◽

Activated Sludge Processes

ABSTRACT The size of bacterial aggregates can determine both nutrient removal and sludge/water separation in activated sludge processes. In this study, the bacterial community structures and network associations of different sized aggregates obtained from a full-scale membrane bioreactor plant over a one-year period were investigated. Our results showed that biodiversity of larger sized aggregates was significantly higher than that of smaller ones and that the bacterial compositions of different sized aggregates differed significantly from each other. Bacteria related to nutrient removal (e.g. denitrification, hydrolysis and fermentation) were found to be significantly more abundant in larger aggregates than smaller ones. Network analysis revealed significant difference in species–species interactions, topological roles of individual OTU and keystone populations among different sized aggregates. Moreover, the occurrence of keystone OTUs affiliated with denitrifiers (Thermomonas) in networks of large and medium aggregates may suggest that denitrification influences bacterial interactions in large and medium aggregates. Overall, our results indicate the aggregates size-dependence of bacterial community separation in activated sludge. The current findings not only can provide guidance for process design and operation optimization, but also highlight the necessity for paying more attentions to the aggregate-based community, metabolic function and gene expression of activated sludge in future studies.

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