Article
Biotechnology & Applied Microbiology
Paula Bucci, Juan C. Alzate Marin, Noemi Zaritzky, Alejandro Caravelli
Summary: This study investigates the effects of different conditions and microbial aggregate sizes on the process of aerobic denitrification. The results demonstrate that nitrogen can be efficiently removed from wastewater through a combination of nitrification and aerobic denitrification without the need for oxygen control. Genomic analysis suggests that heterotrophic nitrification-aerobic denitrification is the main process for nitrogen removal.
JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
(2023)
Article
Engineering, Chemical
Elsayed Mady, Jan Oleszkiewicz, Qiuyan Yuan
Summary: This study investigated the feasibility of applying an anaerobic step-feeding strategy to enhance the performance of granular sequencing batch reactors (GSBRs) in terms of operational stability of the cultivated mature granules and nutrient removal efficiencies. The results showed that operating GSBRs under the effect of fast single feeding mode followed by anaerobic mixing favors stable long-term granule stability.
Article
Environmental Sciences
Geumhee Yun, Zuwhan Yun, Young Kim, Kyungjin Han
Summary: This study investigated the influencing factors and characteristics of granule morphology through long-term monitoring of two types of reactors. The results show that the size and development of granules are closely related to the availability and type of electron acceptors.
Article
Engineering, Chemical
M. Sarvajith, Y. V. Nancharaiah
Summary: Treatment and safe disposal of excess microbial sludge in wastewater treatment plants is challenging due to pathogens, economic and regulatory issues. This study explored the recovery of biopolymers from different biological treatment systems and found that alginate-like exopolymer (ALE) was the dominant biopolymer in all systems. ALE extraction significantly reduced biosolids content and mitigated sludge management challenges, pathogen spread, and improved resource recovery in wastewater treatment plants.
SEPARATION AND PURIFICATION TECHNOLOGY
(2023)
Article
Computer Science, Interdisciplinary Applications
Jenifer Benavides Sanchez, Marianna Vuono, Davide Dionisi
Summary: This study compared the performance of CAS and SBR processes in treating wastewater with different substrate compositions through mathematical modeling, finding that under certain conditions, SBR can remove COD and ammonia nitrogen from wastewater more effectively than CAS.
COMPUTERS & CHEMICAL ENGINEERING
(2021)
Article
Environmental Sciences
Y. V. Nancharaiah, M. Sarvajith, T. V. Krishna Mohan
Summary: Aerobic granular sludge (AGS) is an innovative biotechnology for wastewater treatment. Addition of nucleating agents can improve AGS development while treating low-strength wastewaters. This study investigated AGS formation and biological nutrient removal (BNR) pathways in the presence of nucleating agents during treatment of real domestic wastewater.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Environmental Sciences
Jixiang Wang, Zhongfang Lei, Caixing Tian, Sen Liu, Qian Wang, Kazuya Shimizu, Zhenya Zhang, Yasuhisa Adachi, Duu-Jong Lee
Summary: Biological phosphorus removal involves changes in Ac-, K+, Mg2+, and Ca2+ in wastewater, with the presence of algae not beneficial for PAOs to remove P but more K+ and P uptake by algae in AB-AGS suggesting its potential for manufacturing biofertilizer.
Article
Environmental Sciences
Peng Xu, Zhiyi Xie, Liangsheng Shi, Xiaohui Yan, Zhidong Fu, Jingwei Ma, Wei Zhang, Hongyu Wang, Baokun Xu, Qiulai He
Summary: The availability of nutrients plays a crucial role in determining the efficiency of biological treatment systems. This study evaluated the effects of nutrient deficiencies on aerobic granular sludge treating wastewater. The results showed that both nitrogen and phosphorus deficiencies had significant impacts on effluent qualities, especially nitrogen removal. Different nutrient deficiencies also led to variations in microbial community structure and extracellular polymeric substances. The study provides insights into the stability of aerobic granular sludge for treating low-strength wastewater.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Engineering, Environmental
Tianwei Hao
Summary: This study investigated the response and adaptation mechanisms of granular and flocculent sulfate-reducing bacteria (SRB) sludge to acidic metal-laden wastewater (AMW). The results showed that the flocculent SRB lost more than 50% of their treatment capacity, while the granular SRB maintained a high metal removal rate throughout the trial. The stability of the granular structure and microbial activity was found to be influenced by the extracellular glycosyl compositions.
Article
Environmental Sciences
Dongyue Li, Wei Guo, Dongbo Liang, Jing Zhang, Jun Li, Peilin Li, Yaodong Wu, Xueying Bian, Fan Ding
Summary: This study examined the feasibility of using the SNEDPR-AGSBR process for treating low C/N ratio domestic sewage. The results showed that the rapid start-up and advanced nutrient removal were successfully achieved by selecting slow-growing organisms. The SNEDPR-AGSBR process demonstrated high removal efficiencies for nitrogen and phosphorus, indicating its potential for treating low C/N ratio domestic sewage.
ENVIRONMENTAL RESEARCH
(2022)
Article
Environmental Sciences
Xiaochun Wang, Ji Li, Xiaolei Zhang, Zhonglin Chen, Jimin Shen, Jing Kang
Summary: The study investigated the impact of hydraulic retention time (HRT) on the performance of aerobic granular sludge (AGS) treating swine wastewater in sequencing batch reactors (SBR). Results showed that decreasing HRT from 16 to 8 h improved sedimentation performance and biomass concentration, but further reduction to 4.8 h led to worse AGS performance. AGS process with 8 h HRT exhibited high pollutant removal efficiency and stable microbial community structure.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2021)
Article
Environmental Sciences
Jinchi Yao, Wei Li, Dong Ou, Lei Lei, Muhammad Asif, Yongdi Liu
Summary: The presence of sulfate in hypersaline wastewater enhanced the removal efficiency of chemical oxygen demand and total nitrogen, while reducing the accumulation of nitrite. High-throughput 16S rRNA gene sequencing revealed that Denitromonas and Xanthomarina were the dominant genera in AGS response to mixed salts containing high sulfate.
Article
Engineering, Environmental
Rebeca Pallares-Vega, Lucia Hernandez Leal, Benjamin N. Fletcher, Eduardo Vias-Torres, Markc. M. van Loosdrecht, David G. Weissbrodt, Heike Schmitt
Summary: This study investigated the occurrence and removal patterns of antimicrobial agents, antibiotic resistance genes, and E. coli in wastewater treatment plants. The results showed that wastewater treatment reduced the abundance of genes and E. coli, while partially removing antimicrobial agents, with some still detectable after treatment and accumulating in biosolids. Irrespective of the type of sludge treatment, the removal of genes was significantly reduced with increasing hydraulic loads caused by rainfall, and slightly decreased with increasing turbidity.
Article
Biotechnology & Applied Microbiology
Masaki Miyake, Yoshiaki Hasebe, Kazuki Furusawa, Hiroshi Shiomi, Daisuke Inoue, Michihiko Ike
Summary: By operating a SFD-SBR under high organic loading rate (OLR) conditions with low-strength municipal wastewater, rapid and efficient aerobic granular sludge (AGS) production can be achieved. Maintaining a stable and efficient AGS production under high OLR conditions requires a long settling time during the feeding period.
BIOCHEMICAL ENGINEERING JOURNAL
(2022)
Article
Agricultural Engineering
Zejiao Li, Jixiang Wang, Xingyu Chen, Zhongfang Lei, Tian Yuan, Kazuya Shimizu, Zhenya Zhang, Duu-Jong Lee
Summary: This study found that aerobic phosphorus removal in the algal-bacterial aerobic granular sludge (AGS)-based wastewater treatment system is mainly controlled by macropore and micropore diffusion. The increase in light intensity promotes microalgae metabolism and leads to an increase in wastewater pH. The pH increase has a strong negative correlation with phosphorus uptake by polyphosphate-accumulating organisms and promotes chemical precipitation at a specific calcium to phosphorus ratio.
BIORESOURCE TECHNOLOGY
(2022)
Article
Environmental Sciences
Jie Li, Lin Liu, Xu Huang, Jie Liao, Chaoxiang Liu
Summary: The study found that oyster shell was the optimal substrate for enhancing the anammox-driven process, showing the highest nitrogen removal rates and resistance to nitrogen load. The anammox process played a crucial role in enhancing nitrogen treatment performance in all systems, with oyster shell system exhibiting the best removal ability.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2022)
Article
Environmental Sciences
Tao Xiang, Hong Liang, Dawen Gao
Summary: The AnAOB granular sludge reactor showed faster recovery and higher nitrogen removal performance compared to the AOB-AnAOB granular sludge reactor after long-term storage, indicating better application potential and more active characteristics of aggregation metabolism.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Green & Sustainable Science & Technology
Weifeng Deng, Litao Wang, Lang Cheng, Wenbo Yang, Dawen Gao
Summary: This paper reviewed the recent advances of anammox based processes for mature landfill leachate treatment and suggested some improvements to enhance the process efficiency.
Article
Agricultural Engineering
Dawen Gao, Yuqi Li, Hong Liang
Summary: This paper reviews the effect of carrier properties on the development of AnAOB biofilm, introduces the application status of organic-based, inorganic-based, and gel carriers, and summarizes the carrier modification methods and purposes. Four important aspects of the desirable carrier are proposed, and the future application directions of novel carriers are highlighted.
BIORESOURCE TECHNOLOGY
(2022)
Article
Environmental Sciences
Dawen Gao, Weijie Wang, Weifeng Gao, Qingbo Zeng, Hong Liang
Summary: Autumn freeze-thaw period has a significant impact on soil temperature, moisture, nutrients, and the structure and diversity of soil microbial community. Different wetlands showed varying greenhouse gas fluxes, with soil temperature being a significant factor for CH4 flux. The global warming potentials during the autumn freeze-thaw period were found to be relatively high.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2022)
Article
Environmental Sciences
Weifeng Gao, Dawen Gao, Liquan Song, Houcai Sheng, Tijiu Cai, Hong Liang
Summary: Non-growing season nitrous oxide (N2O) emissions from permafrost regions are an essential component of annual emissions, contributing significantly to the annual budget. The driving factors of non-growing season N2O emissions differ from those of the growing season and the entire observation period, mainly influenced by soil temperature.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2022)
Review
Environmental Sciences
Mohammad Nabi, Hong Liang, Lang Cheng, Wenbo Yang, Dawen Gao
Summary: Globally, around 70% of waste is disposed of in open dumps or landfill sites, which generate leachate containing high concentrations of organic and inorganic compounds. Anaerobic digestion of landfill leachate is an environmentally-friendly method that converts organic compounds into methane-rich biogas. However, poor system stability, low methanogenic activity, and VFAs accumulation hinder the widespread application of anaerobic digestion. This review focuses on the use of conductive materials in landfill leachate treatment systems and discusses their impact on microbial growth, waste metabolism, methane production, and interspecies electron transfer.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2022)
Article
Environmental Sciences
Weifeng Gao, Dawen Gao, Tijiu Cai, Hong Liang
Summary: This study investigated the effects of different permafrost wetland types on greenhouse gas emissions in the Daxing'an Mountains. The results showed that N2O emissions were influenced by the NO3--N content, while CO2 emissions were driven by soil temperature, water table level, and NO3--N content. CH4 emissions were affected by soil temperature and water table level. The study concluded that the permafrost wetland types significantly affected the emissions of N2O, CO2, and CH4.
JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES
(2022)
Article
Environmental Sciences
Lin Liu, Xin Yu, Daizhuo Wu, Jianqiang Su
Summary: This study investigates the influence of eukaryote microalgae on the antibiotic resistance gene (ARG) profile of symbiotic bacteria. The results show that the symbiosis of microalgae can decrease the abundance of ARGs in bacteria, and there is a strong correlation between ARGs and mobile genetic elements (MGEs).
ENVIRONMENTAL POLLUTION
(2022)
Article
Green & Sustainable Science & Technology
Lin Liu, Yu Xin, Zhong-Hua Tong, Yu-Ming Zheng, Jia-Fang Xie, Quan-Bao Zhao, Han-Qing Yu
Summary: Aerobic algae-bacteria granular consortia (AAG) is a novel biotechnology for wastewater treatment. This study investigated the influence of storage process on AAG, finding that AAG could maintain its granular structure under different storage conditions. Storage at higher temperatures resulted in better performance of AAG. Storage time was negatively related to EPS concentration and polysaccharides/protein ratio of AAG, while illumination was conducive to maintaining the polysaccharides/protein ratio. During the activation process, temperature and illumination were significant factors influencing the relative abundance of target microalgae.
JOURNAL OF CLEANER PRODUCTION
(2022)
Article
Environmental Sciences
Tao Xiang, Hong Liang, Dawen Gao
Summary: This study investigated the effects of exogenous N2H4 on AnAOB and found that low concentration dosing of N2H4 can promote SAA, while high concentration dosing can trigger the self-protection mechanism of AnAOB. Intermittent addition of low concentration N2H4 is conducive to the long-term stable operation of anammox process.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2022)
Article
Engineering, Environmental
Jie Li, Lin Liu, Yu-Ming Zheng, Lin Ma, Quan-Bao Zhao, Chao-Xiang Liu
Summary: This study found that plants (Phragmites) play a significant role in the anammox-driven wetlands, enhancing the nitrogen transformation. The proportion of anammox process in nitrogen metabolism was estimated to be 45-63% in plant groups. The presence of plants significantly increased the total nitrogen removal efficiency and the abundance of anammox bacteria.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Environmental Sciences
Lin Liu, Shan-Bin Guang, Yu Xin, Jie Li, Guo-Fu Lin, Li-Qin Zeng, Shao-Qin He, Yu-Ming Zheng, Guan-Yu Chen, Quan-Bao Zhao
Summary: This study aimed to understand the characteristics and influencing factors of antibiotic resistant genes (ARGs) in the subtropical drinking water river-reservoir system. The results showed that various environmental factors had significant impacts on the abundance and distribution of ARGs, and bacterial host and resistance mechanisms were also correlated with ARGs.
ENVIRONMENTAL POLLUTION
(2023)
Article
Environmental Sciences
Lin Liu, Yu Xin, Shan-Bin Guang, Guo-Fu Lin, Chao-Xiang Liu, Li-Qin Zeng, Shao-Qin He, Yu-Ming Zheng, Guan-Yu Chen, Quan-Bao Zhao
Summary: This study investigated the dynamics of planktonic microbial community and its metabolism processes in a subtropical drinking water river-reservoir system. The results showed that seasonal variation had a greater influence on microbial community and biological metabolism, with Proteobacteria and Actinobacteria being the most diverse phyla. Environmental factors such as total organic carbon, total phosphorus, and temperature significantly affected microbial diversity. The assembly of microbial community was mainly driven by stochastic processes, while niche-based processes played a secondary role. The study highlights the importance of multiple abiotic and biotic factors in shaping the microbial community and its metabolism in this type of system.
ENVIRONMENTAL RESEARCH
(2023)
Article
Engineering, Environmental
Claude Kiki, Dan Qin, Lin Liu, Min Qiao, Bob Adyari, Binessi Edouard Ifon, Adenike Adeoye, Longji Zhu, Li Cui, Qian Sun
Summary: This article examines the performance of bacterial granular sludge (BGS) and microalgal-bacterial granular sludge (MBGS) systems for antibiotic wastewater treatment and antibiotic resistance gene (ARG) mitigation. The MBGS shows superior potential, higher nutrient removal, and improved antibiotic removal, while reducing the dissemination of ARGs in the effluent and biomass compared to the BGS bioreactor.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)