Article
Microbiology
Christian White, Edmund Antell, Sarah L. Schwartz, Jennifer E. Lawrence, Ray Keren, Lijie Zhou, Ke Yu, Weiqin Zhuang, Lisa Alvarez-Cohen
Summary: Anaerobic ammonium oxidizing (anammox) bacteria are used for efficient nitrogen removal in wastewater treatment plants. The ratio of ammonium to nitrite (NH4+:NO2-) can influence the interactions between anammox bacteria and heterotrophic bacteria. Understanding these interactions can lead to more stable bioreactor operation under variable nitrogen loading ratios.
FRONTIERS IN MICROBIOLOGY
(2023)
Article
Engineering, Environmental
Xingyu Jiang, Changqing Liu, Jian Cai, Yang Hu, Keqiang Shao, Xiangming Tang, Yi Gong, Xiaolong Yao, Qiujin Xu, Guang Gao
Summary: This study investigates the modulation of denitrification and DNRA rates by gene abundances and environmental factors in eutrophic lakes. The results indicate that denitrification rates increase with eutrophication, while DNRA rates do not. The nitrification process provides ample nitrate for denitrification, and certain microbial genera are responsible for these processes. Further eutrophication indirectly affects denitrification and DNRA rates through modulation of N-cycling microbe gene abundances.
Article
Engineering, Environmental
Junkai Gao, Guanglong Liu, Xiaowen Li, Mengjuan Tang, Xiuyun Cao, Yiyong Zhou, Chunlei Song
Summary: This study investigated the impact of organic carbon quantity and composition on nitrate reduction pathways in two basins of Lake Chaohu in Hefei City, China. It was found that the serious algal bloom in the west basin resulted in higher organic carbon accumulation and nitrate deficiency, leading to a high C/NO3--N ratio. This triggered dissimilatory nitrate reduction to ammonium (DNRA) and specific bacterial communities played a role in this process.
Article
Environmental Sciences
Shengjie Li, Zhuo Jiang, Guodong Ji
Summary: The fate of nitrogen is influenced by competition between nitrate reduction pathways, with denitrification removing nitrogen to the atmosphere and DNRA retaining nitrate as ammonia. This study explored the impact of five sulfur forms as electron donors on nitrate fate. The results showed that thiosulfate had the highest nitrate reduction rate, stimulating denitrification and inhibiting DNRA. Elemental sulfur, on the other hand, stimulated both denitrification and DNRA. Metagenomic analysis revealed links between sulfur sources, nitrate reduction pathways, and microbial populations.
ENVIRONMENTAL POLLUTION
(2022)
Article
Engineering, Environmental
Andres Pichel, Andrea Fra, Nicolas Morales, Jose Luis Campos, Ramon Mendez, Anuska Mosquera-Corral, Angeles Val del Rio
Summary: This study demonstrates that despite the higher sCOD/N ratios in OFMSW digestate, good synergy can be achieved through AS pre-treatment in the PN-AMX process, resulting in better effluent quality and lower nitrogen removal rates.
JOURNAL OF HAZARDOUS MATERIALS
(2021)
Article
Environmental Sciences
Dongyao Sun, Jiafang Huang, Min Luo, Cheng Chen, Xue Lan, Weifang Hu
Summary: Intensive aquaculture in estuaries and coasts has led to ecological and environmental problems. Among nitrogen transformation pathways, dissimilatory nitrate reduction plays a crucial role in regulating reactive nitrogen. This study investigated the three sediment processes of nitrate reduction and found that denitrification was the dominant pathway. Environmental factors such as C and N substrates and salinity significantly influenced nitrate reduction. The nitrogen losses from denitrification and anaerobic ammonium oxidation were substantial, indicating the importance of coastal reclamation in nitrogen removal.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Agricultural Engineering
Hao Sheng, Rui Weng, Yan He, Zheng Wei, Yanmei Yang, Jinghan Chen, Minsheng Huang, Gongming Zhou
Summary: This study identified a nitrate-calcium-based pathway that accelerated the start-up of anammox. Calcium nitrate induced partial denitrification to provide nitrite for anammox, while also increasing the contribution of dissimilatory nitrate reduction to ammonium (DNRA). This mutualistic symbiosis among denitrification, DNRA, and anammox in the calcium nitrate-added systems explained the accelerated start-up of anammox.
BIORESOURCE TECHNOLOGY
(2021)
Article
Engineering, Environmental
Aomei Guan, Weixiao Qi, Qiang Peng, Jiemin Zhou, Yaohui Bai, Jiuhui Qu
Summary: The study revealed that the antibiotic sulfamethoxazole has complex effects on nitrogen reduction processes in aquatic ecosystems, altering the activities of denitrification, anammox, and dissimilatory nitrate reduction to ammonium under different environmental conditions, leading to a shift in nitrogen conversion direction.
JOURNAL OF HAZARDOUS MATERIALS
(2022)
Article
Agricultural Engineering
Yuan Sui, You-Wei Cui, Ji-Lin Huang, Meng-Jiao Xu
Summary: The feast/famine ratio was found to regulate the population succession of autotrophic ammonia oxidizing bacteria (AOB) and heterotrophic nitrification-aerobic denitrification (HN-AD) bacteria, providing a solution for enriching HN-AD bacteria in halophilic aerobic granular sludge (HAGS) systems.
BIORESOURCE TECHNOLOGY
(2024)
Article
Microbiology
Samuel J. Bryson, Kristopher A. Hunt, David A. Stahl, Mari-Karoliina H. Winkler
Summary: This study investigated the differences in microbial community structure and nitrogen transforming functions under one-stage and two-stage reactor configurations. It was found that oxygen availability and gradient in one-stage systems provided a larger niche space for heterotrophic populations compared to the homogeneous anoxic environment in two-stage systems, impacting the competition for carbon substrates between denitrifying and DNRA heterotrophs.
FRONTIERS IN MICROBIOLOGY
(2022)
Article
Engineering, Environmental
Panqing Qi, Dejun Sun, Gaixin Zhang, Dongxia Li, Tao Wu, Yujiang Li
Summary: This study investigates the effects of bio-augmentation with DNRA bacteria on the durability of nitrate-mediated souring control. The findings reveal that nitrate amendment combined with bio-augmentation effectively controls souring and enhances the durability of control in anaerobic water bodies. Injection of nitrate before souring fails to persistently control souring, while injection after souring shows promising results in controlling souring.
Article
Environmental Sciences
Xiaowen Li, Qinghui Deng, Zhimin Zhang, Dong Bai, Zhenghan Liu, Xiuyun Cao, Yiyong Zhou, Chunlei Song
Summary: This study investigated the effects of sulfur cycle and enzyme activity on dissimilatory nitrate reduction processes (DNRPs) in natural and human-modified heterotrophic sediments. The key driver of DNRPs was found to be glucosidase activity (GLU), and the sulfur cycle played a general restrictive role in the regulation and partitioning of DNRPs.
Article
Environmental Sciences
Ruo-Chen Zhang, Chuan Chen, Xi-Jun Xu, Duu-Jong Lee, Nan-Qi Ren
Summary: Compared to autotrophic and heterotrophic denitrification processes, the integrated autotrophic and heterotrophic de-nitrification (IAHD) has a wider range of applications in wastewater containing organic carbon, nitrogen, and sulfur. The interaction between heterotrophic and autotrophic denitrificans in the IAHD system ensures efficient co-removal of sulfur, nitrogen, and carbon. Experimental results showed that Pseudomonas C27 had higher metabolic activity than T. denitrificans at specific sulfide concentrations, and a mix of Pseudomonas C27 and T. denitrificans at different ratios led to the highest sulfide removal efficiency.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Environmental Sciences
Feng Sun, Qinghui Deng, Xiaowen Li, Mengjuan Tang, Xufa Ma, Xiuyun Cao, Yiyong Zhou, Chunlei Song
Summary: The study found that high organic carbon content in matrix facilitated dissimilatory nitrate reduction to ammonium (DNRA) over denitrification (DEN), while low organic carbon content promoted DEN. It was also observed that using corn cob as OC source in biofilters was more effective than bagasse due to slow and continuous release of organic carbon. Choosing suitable OC source and regulating its dosage are crucial for enhancing nitrate removal and reducing ammonium accumulation in biofilters.
Review
Environmental Sciences
Hoang Dung Nguyen, Sandhya Babel
Summary: This study critically reviews the nitrogen removal process and influencing factors in various MFC configurations, highlighting shortcut nitrification-autotrophic denitrification and heterotrophic anodic denitrification as promising options, although further evaluation on efficiency and gas emissions is needed. The selection of MFC configuration depends on the nature of the wastewater.
ENVIRONMENTAL RESEARCH
(2022)
Article
Environmental Sciences
L. Corbala-Robles, E. I. P. Volcke
Summary: This study evaluated the need for and effects of coupling mass and heat balances in modeling studies for a biological nitrogen removal process in water resource recovery facilities. The results showed that mass balances are sufficient for evaluating nitrogen removal efficiency and effluent nitrogen concentrations, while coupling of mass and heat balances may not be necessary for predicting temperature changes or evaluating heat recovery potential.
ENVIRONMENTAL TECHNOLOGY
(2021)
Article
Environmental Sciences
Simone Visigalli, Andrea Turolla, Giacomo Bellandi, Micol Bellucci, Elisa Clagnan, Lorenzo Brusetti, Mingsheng Jia, Roberto Di Cosmo, Glauco Menin, Martina Bargna, Giovanni Bergna, Roberto Canziani
Summary: Digital textile printing (DTP) is an emerging technology with rapid global expansion, but wastewater treatment issues are prominent. Research has shown that utilizing the partial nitritation/anammox process for DTP wastewater treatment at a laboratory scale is feasible, and simulation results indicate significant benefits of on-site decentralized treatment, including reduced energy consumption, greenhouse gas emissions, and sludge production.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2021)
Article
Environmental Sciences
Xinyu Wan, Janis E. Baeten, Michele Laureni, Eveline I. P. Volcke
Summary: This study compared the effects of different aeration control strategies in a partial nitritation-anammox reactor with granular sludge. The study found that controlling aeration based on effluent ammonium concentration resulted in high nitrogen removal and low N2O emissions, even in the presence of flocs. Fluctuations in floc fractions had a significant impact on nitrogen removal and N2O emissions under DO control, but less effect under constant airflow and effluent ammonium control.
Article
Environmental Sciences
S. O. Decru, J. E. Baeten, Y-X Cui, D. Wu, G-H Chen, E. I. P. Volcke
Summary: The study developed a biofilm model for sulfur-based denitrification in a moving bed biofilm reactor, showing that the substrate affinity of sulfur-oxidizing bacteria for elemental sulfur was the most sensitive parameter. Simulation results indicated that increasing the specific nitrogen loading rate resulted in an almost linear increase in specific nitrogen removal rate. It was also found that the specific nitrogen loading rate could be increased by adjusting hydraulic retention time, carrier filling ratio, or biofilm thickness while maintaining nitrogen removal efficiencies above 70%.
ENVIRONMENTAL TECHNOLOGY
(2022)
Article
Engineering, Environmental
T. Bressani-Ribeiro, P. G. S. Almeida, C. A. L. Chernicharo, E. I. P. Volcke
Summary: Anaerobic sewage treatment is effective in warm climate regions, and sponge-bed trickling filters play a crucial role in removing residual organic carbon and nitrogen. However, the efficiency of nitrogen removal in SBTFs treating anaerobic effluent is influenced by influent characteristics and operating conditions, requiring further process optimization.
Article
Biotechnology & Applied Microbiology
Xinyu Wan, Eveline I. P. Volcke
Summary: This study applied mathematical modeling to analyze the formation and emission dynamics of N2O in a partial nitritation-anammox reactor, and developed strategies to mitigate N2O emissions. The model accurately predicted and characterized N2O emissions through calibration and validation.
BIOTECHNOLOGY AND BIOENGINEERING
(2022)
Article
Engineering, Environmental
Laurence Strubbe, Margot Pennewaerde, Janis E. Baeten, Eveline I. P. Volcke
Summary: The use of aerobic granular sludge in continuous wastewater treatment plants can increase treatment capacity, but the potential diffusion limitation may counteract the positive effects of improved settling. Optimization measures, such as increasing reactor volume fraction and adjusting oxygen set-points, can enhance the treatment efficiency and reduce energy consumption in continuous systems.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Environmental Sciences
Xinyu Wan, Michele Laureni, Mingsheng Jia, Eveline I. P. Volcke
Summary: This study demonstrated that the presence of influent organics combined with proper aeration control strategies and floc management can significantly reduce N2O emissions without compromising nitrogen removal efficiency during one-stage partial nitritation-anammox processes.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Engineering, Environmental
Janis E. Baeten, Christophe Walgraeve, Rafael Cesar Granja, Mark C. M. van Loosdrecht, Eveline I. P. Volcke
Summary: This study investigated the fate of dissolved methane in aerobic granular sludge reactors, finding that the conversion efficiency of dissolved methane is low in these reactors, mainly due to the accumulation of high concentrations during feeding phases favoring stripping over conversion. Based on these findings, strategies were proposed to reduce methane emissions from wastewater treatment plants with sequentially operated reactors.
Article
Engineering, Environmental
Ka Leung Lam, Kimberly Solon, Mingsheng Jia, Eveline I. P. Volcke, Jan Peter van der Hoek
Summary: Recovering phosphorus from wastewater in more concentrated forms has the potential to sustainably recirculate phosphorus from cities to agriculture. Life cycle assessment (LCA) can be used to evaluate the environmental sustainability of wastewater-based phosphorus recovery processes or products. The study demonstrates the application of an end-user perspective in assessing the life cycle environmental impacts of substituting conventional phosphorus fertilizers with wastewater-derived phosphorus products. The results show that the substitution reduces environmental impacts in most scenarios and highlights the importance of long-term impacts of using wastewater-derived products.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2022)
Article
Engineering, Environmental
P. Carrera, L. Strubbe, A. Val del Rio, A. Mosquera-Corral, E. I. P. Volcke
Summary: The effect of salinity on the treatment of fish-canning wastewater using aerobic granular sludge was assessed using a one-dimensional biofilm model. The model incorporated a non-competitive inhibition term to describe the salt inhibition of heterotrophic and nitrifying bacteria. The model was calibrated and validated using experimental lab-scale data, and accurately predicted the removal of COD and nitrogen species under different salinity conditions.
ENVIRONMENTAL SCIENCE-WATER RESEARCH & TECHNOLOGY
(2023)
Article
Agricultural Engineering
Yankai Xie, Mingsheng Jia, Fabian De Wilde, Katrien Daeninck, Haydee De Clippeleir, Willy Verstraete, Siegfried E. Vlaeminck
Summary: This study explores the feasibility of cost-effective partial nitritation/anammox (PN/A) in packed-bed trickling filters (TFs). It finds that using the inexpensive Argex expanded clay can achieve similar nitrogen removal rates as commercially used plastics. The top-only ventilation at an optimum hydraulic loading rate of 1.8 m3 m-2 h-1 can remove around 60% of the total nitrogen load and achieve relatively low NO3--N accumulation. The results demonstrate that TFs are suitable for low-energy shortcut nitrogen removal.
BIORESOURCE TECHNOLOGY
(2023)
Article
Environmental Sciences
Jinte Zou, Lei Cai, Jianrui Lin, Ruyi Wang, Jun Li, Mingsheng Jia
Summary: This study investigated the effect of granule size and sludge structure on the hydrolysis and acidification of aerobic granular sludge. The findings showed that aerobic granular sludge exhibited higher soluble chemical oxygen demand (SCOD) dissolution and total volatile fatty acids (TVFA) production compared to conventional activated sludge. The optimal granule size for AGS fermentation was found to be 500-1600 μm.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2023)
Article
Engineering, Environmental
Quan H. Le, Peter J. T. Verheijen, Mark C. M. van Loosdrecht, Eveline I. P. Volcke
Summary: This study focuses on the application of data reconciliation to dynamic wastewater treatment processes. The researchers studied the SHARON partial nitritation process and found that splitting the long-term dynamic data into subsets corresponding to different pseudo-steady-state operations improved the detection of gross errors and allowed for a higher number of variables to be reconciled. They also discovered that the infiltration of air and errors in grab sampling had a significant impact on calculating N2O emissions.
ENVIRONMENTAL SCIENCE-WATER RESEARCH & TECHNOLOGY
(2022)