Characteristics and transformations of dissolved organic nitrogen in municipal biological nitrogen removal wastewater treatment plants

In order to meet the more stringent environmental regulations, the adaptive and optimal control strategies should be investigated for the biological nitrogen removal (BNR) processes in wastewater treatment plants. Because of the complex nature of the microbial metabolism involved, the conventional mechanistic models for nitrogen removal are difficult to formulate and the existing ones are still uncertain to some extent. Alternatively, the machine learning methods have been investigated as black-box modelling techniques. A new approach, Support Vector Machine (SVM) was proposed to be used to model the biological nitrogen removal processes in this thesis. Specifically, LS-SVM, a simplified formulation of SVM, was applied to predict the concentration of nitrate & nitrite (NO). The simulation results indicate that the proposed method has better generalization performance in comparison with generalized regression neural network, especially under weather conditions that are quite different from the training weather conditions.

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Characteristics of dissolved organic nitrogen in effluent from a biological nitrogen removal process using sludge alkaline fermentation liquid as an external carbon source

Water Research ◽

10.1016/j.watres.2020.115741 ◽

2020 ◽

Vol 176 ◽

pp. 115741 ◽

Cited By ~ 5

Author(s):

Haidong Hu ◽

Sijia Ma ◽

Xuxiang Zhang ◽

Hongqiang Ren

Keyword(s):

Carbon Source ◽

Nitrogen Removal ◽

Dissolved Organic Nitrogen ◽

Organic Nitrogen ◽

Biological Nitrogen Removal ◽

External Carbon Source ◽

Removal Process ◽

Fermentation Liquid ◽

Biological Nitrogen

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Effect of COD:N ratio on biological nitrogen removal using full-scale step-feed in municipal wastewater treatment plants

Sustainable Environment Research ◽

10.1186/s42834-020-00064-6 ◽

2020 ◽

Vol 30 (1) ◽

Author(s):

Supaporn Phanwilai ◽

Pongsak Noophan ◽

Chi-Wang Li ◽

Kwang-Ho Choo

Keyword(s):

Wastewater Treatment ◽

Nitrogen Removal ◽

Municipal Wastewater ◽

Wastewater Treatment Plants ◽

Full Scale ◽

Biological Nitrogen Removal ◽

Municipal Wastewater Treatment ◽

Municipal Wastewater Treatment Plants ◽

Scale Step ◽

Biological Nitrogen

Abstract This study investigated the effect of low and high chemical oxygen demand (COD):N ratios on biological nitrogen removal and microbial distributions in full-scale step-feed (SF) municipal wastewater treatment plants (WWTPs) in Thailand (SF1) and Taiwan (SF2). The SF1 WWTP had a low COD:N (4:1) ratio, a long solids retention time (SRT) (> 60 d), and low dissolved oxygen (DO) conditions (0.2 mg L− 1 in anoxic tank and 0.9 mg L− 1 in aerobic tank). The total nitrogen (TN) removal efficiency was 48%. The SF2 WWTP had a high COD:N (10:1) ratio, a short SRT (7 d), and high DO (0.6 mg L− 1 in anoxic tank and 1.8 mg L− 1 in aerobic tank). The TN removal efficiency was 61%. The nitrification and denitrification rates from these two plants were inadequate. Using a quantitative polymerase chain reaction (qPCR) technique, the populations of ammonium oxidizing bacteria (AOB) and ammonium oxidizing archaea were quantified. Measurement of ammonia monooxygenase (amoA) gene abundances identified these AOB: Nitrosomonas sp., Nitrosospira sp., Nitrosoccus sp. and Zoogloea sp. Higher amounts of the archaeal-amoA gene were found with long SRT, lower DO and COD:N ratios. Abundance of Nitrobacter sp. was slightly higher than Nitrospira sp. at the SF1, while abundance of Nitrobacter sp. was two orders of magnitude greater than Nitrospira sp. at the SF2. More denitrifying bacteria were of the nirS-type than the nirK-type, especially at higher COD:N ratio. Most bacteria belong to the phyla Acidobacteria, Actinobacteria Bacteroidetes, Chloroflexi, Proteobacteria. The results from this work showed that insufficient carbon sources at the SF1 and high DO concentration in anoxic tank of SF2 adversely affected nitrogen removal efficiencies. In further research work, advanced techniques on the next generation sequencing with different variable regions should be recommended in full-scale WWTPs.

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Characteristics of Dissolved Organic Nitrogen in Municipal and Biological Nitrogen Removal Wastewater Treatment Plants in Jordan

Transylvanian Review of Systematical and Ecological Research ◽

10.2478/trser-2019-0008 ◽

2019 ◽

Vol 21 (2) ◽

pp. 1-12

Author(s):

Mohammed Ali Wedyan ◽

Esam Qnais ◽

Khalil Altaif ◽

Abdel Al-Tawaha

Keyword(s):

Amino Acids ◽

Free Amino ◽

Dissolved Organic Nitrogen ◽

Organic Nitrogen ◽

Wastewater Treatment Plants ◽

Algal Growth ◽

Biological Nitrogen Removal ◽

Future Improvement ◽

Hydrophilic Compounds ◽

Biological Nitrogen

Abstract The investigation is conducted on the biochemical form and characteristics of wastewater-derived DON in three different WWTPs in Jordan. The main eliminations of DON and biodegradable dissolved organic nitrogen (BDON) noticed along the treatment course are in the Irbid (ITP). Dissolved combined amino acids (DCAA) and dissolved free amino acids (DFAA) in the outlet accounted for less than 4% of the outlet DON of all plants. The DON from the outlet was composed of 90% hydrophilic compounds which stimulate algal growth. The study provided information for future improvement of WWTPs of Jordan and for adjusting the assortment of DON elimination systems to comply with stricter limits.

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Support vector machines for environmental informatics : application to biological nitrogen removal in wastewater treatment plants

10.32920/ryerson.14646114.v1 ◽

2021 ◽

Author(s):

Yinghui Yang

Keyword(s):

Wastewater Treatment ◽

Nitrogen Removal ◽

Wastewater Treatment Plants ◽

Control Strategies ◽

Weather Conditions ◽

Support Vector ◽

Biological Nitrogen Removal ◽

Complex Nature ◽

Generalized Regression Neural Network ◽

Biological Nitrogen

In order to meet the more stringent environmental regulations, the adaptive and optimal control strategies should be investigated for the biological nitrogen removal (BNR) processes in wastewater treatment plants. Because of the complex nature of the microbial metabolism involved, the conventional mechanistic models for nitrogen removal are difficult to formulate and the existing ones are still uncertain to some extent. Alternatively, the machine learning methods have been investigated as black-box modelling techniques. A new approach, Support Vector Machine (SVM) was proposed to be used to model the biological nitrogen removal processes in this thesis. Specifically, LS-SVM, a simplified formulation of SVM, was applied to predict the concentration of nitrate & nitrite (NO). The simulation results indicate that the proposed method has better generalization performance in comparison with generalized regression neural network, especially under weather conditions that are quite different from the training weather conditions.

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Improving the Biological Nitrogen Removal Process in Pharmaceutical Wastewater Treatment Plants: A Case Study

Environmental Technology ◽

10.1080/09593332508618462 ◽

2004 ◽

Vol 25 (4) ◽

pp. 423-431 ◽

Cited By ~ 3

Author(s):

M. Torrijos ◽

J. Carrera ◽

J. Lafuente

Keyword(s):

Wastewater Treatment ◽

Nitrogen Removal ◽

Wastewater Treatment Plants ◽

Biological Nitrogen Removal ◽

Pharmaceutical Wastewater ◽

Removal Process ◽

Biological Nitrogen ◽

Pharmaceutical Wastewater Treatment Plants

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Conditions and technologies of biological wastewater treatment in Hungary

Water Science & Technology ◽

10.2166/wst.2012.062 ◽

2012 ◽

Vol 65 (9) ◽

pp. 1676-1683 ◽

Cited By ~ 4

Author(s):

G. M. Tardy ◽

V. Bakos ◽

A. Jobbágy

Keyword(s):

Wastewater Treatment ◽

Carbon Source ◽

Nitrogen Removal ◽

Wastewater Treatment Plants ◽

Treatment Temperature ◽

Low Carbon ◽

Biological Phosphorus Removal ◽

Wastewater Quality ◽

Removal Technologies ◽

Biological Nitrogen

A survey has been carried out involving 55 Hungarian wastewater treatment plants in order to evaluate the wastewater quality, the applied technologies and the resultant problems. Characteristically the treatment temperature is very wide-ranging from less than 10 °C to higher than 26 °C. Influent quality proved to be very variable regarding both the organic matter (typical COD concentration range 600–1,200 mg l−1) and the nitrogen content (typical NH4-N concentration range 40–80 mg l−1). As a consequence, significant differences have been found in the carbon availability for denitrification from site to site. Forty two percent of the influents proved to lack an appropriate carbon source. As a consequence of carbon deficiency as well as technologies designed and/or operated with non-efficient denitrification, rising sludge in the secondary clarifiers typically occurs especially in summer. In case studies, application of intermittent aeration, low DO reactors, biofilters and anammox processes have been evaluated, as different biological nitrogen removal technologies. With low carbon source availability, favoring denitrification over enhanced biological phosphorus removal has led to an improved nitrogen removal.

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Characterization of slowly-biodegradable organic compounds and hydrolysis kinetics in tropical wastewater for biological nitrogen removal

Water Science & Technology ◽

10.2166/wst.2020.077 ◽

2020 ◽

Vol 81 (1) ◽

pp. 71-80 ◽

Cited By ~ 2

Author(s):

Seow Wah How ◽

Jia Huey Sin ◽

Sharon Ying Ying Wong ◽

Pek Boon Lim ◽

Alijah Mohd Aris ◽

...

Keyword(s):

Nitrogen Removal ◽

Uptake Rate ◽

Wastewater Treatment Plants ◽

Oxygen Demand ◽

Hydrolysis Rate ◽

Biological Nitrogen Removal ◽

Tropical Region ◽

Kinetic Coefficients ◽

Wastewater Samples ◽

Biological Nitrogen

Abstract Many developing countries, mostly situated in the tropical region, have incorporated a biological nitrogen removal process into their wastewater treatment plants (WWTPs). Existing wastewater characteristic data suggested that the soluble chemical oxygen demand (COD) in tropical wastewater is not sufficient for denitrification. Warm wastewater temperature (30 °C) in the tropical region may accelerate the hydrolysis of particulate settleable solids (PSS) to provide slowly-biodegradable COD (sbCOD) for denitrification. This study aimed to characterize the different fractions of COD in several sources of low COD-to-nitrogen (COD/N) tropical wastewater. We characterized the wastewater samples from six WWTPs in Malaysia for 22 months. We determined the fractions of COD in the wastewater by nitrate uptake rate experiments. The PSS hydrolysis kinetic coefficients were determined at tropical temperature using an oxygen uptake rate experiment. The wastewater samples were low in readily-biodegradable COD (rbCOD), which made up 3–40% of total COD (TCOD). Most of the biodegradable organics were in the form of sbCOD (15–60% of TCOD), which was sufficient for complete denitrification. The PSS hydrolysis rate was two times higher than that at 20 °C. The high PSS hydrolysis rate may provide sufficient sbCOD to achieve effective biological nitrogen removal at WWTPs in the tropical region.

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