Article
Agricultural Engineering
Jing Ding, Xinjie Gao, Yi Peng, Yongzhen Peng, Qiong Zhang, Xiyao Li, Shuying Wang
Summary: The study optimized the quantitative distribution of anaerobic carbon source removal pathways for the first time, improving the endogenous denitrification rate. The results showed an increase in NO3- removal rate and the abundance of glycogen accumulating organisms, providing an effective strategy to improve postdenitrification efficiency.
BIORESOURCE TECHNOLOGY
(2022)
Article
Environmental Sciences
Weihua Zhao, Xuejun Bi, Yongzhen Peng, Meng Bai
Summary: This paper discusses the metabolic mechanisms, process applications, community abundance, and influencing factors of phosphorus-accumulating organisms (PAOs) in wastewater treatment. It identifies novel PAOs, such as Dechloromonas and Tetrasphaera, which can remove phosphorus through different metabolic pathways. Dechloromonas can achieve simultaneous nitrogen and phosphorus removal in an anoxic environment, reducing carbon source requirements and energy consumption.
Review
Engineering, Environmental
Sheila M. Saia, Hunter J. Carrick, Anthony R. Buda, John M. Regan, M. Todd Walter
Summary: Despite advances in wastewater treatment research on phosphorus cycling, there is still limited application in reducing agricultural phosphorus loading. Interdisciplinary research is needed to improve agricultural phosphorus management strategies and achieve water quality goals.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2021)
Article
Agricultural Engineering
Yangang Lin, Yawen Sun, Liyuan Zhang, Qiong Zhang, Xiyao Li, Jun Sui, Yongzhen Peng
Summary: Balancing the removal of nitrogen and phosphorus in municipal wastewater under carbon limitation remains challenging. The key parameter in achieving this balance is the COD-to-PO43--P ratio. By operating an A(2)/O-BCO system for 205 days, it was found that increasing the COD/P ratio deteriorated the nitrogen removal performance, while decreasing it led to the proliferation of Ca.Competibacter and an increase in nitrogen removal. The nitrogen and phosphorus removal efficiency reached up to 79.3% and 95.2%. Overall, establishing a balance between DGAOs and DPAOs through strengthening the effect of DGAOs can improve nutrient removal performance and enhance the stability and efficiency of the system.
BIORESOURCE TECHNOLOGY
(2023)
Article
Engineering, Environmental
Timothy Paez-Watson, Mark C. M. van Loosdrecht, S. Aljoscha Wahl
Summary: Understanding microbial communities and their regulation is important for new technologies. Resource allocation and biosynthesis in microbial communities are poorly understood. In this study, metabolic flux analysis was used to study the optimal phenotype of polyphosphate accumulating organisms (PAOs). The results validate limited anaerobic biosynthesis in PAOs and identify temperature-dependent resource allocation strategies.
Article
Engineering, Environmental
Qingan Meng, Wei Zeng, Zhiwei Fan, Shuangshuang Li, Yongzhen Peng
Summary: This study investigated the impact of sulfide generated from sulfate reduction in wastewater on the stability of enhanced biological phosphorus removal (EBPR). The results showed that the metabolic activity of polyphosphate accumulating organisms (PAOs) and glycogen accumulating organisms (GAOs) was mainly influenced by hydrogen sulfide (H2S) concentration. H2S promoted the catabolism of PAOs and GAOs at lower concentrations but inhibited it at higher concentrations. PAOs were more significantly affected by H2S, resulting in poorer aerobic metabolism and recovery compared to GAOs. Additionally, sulfides facilitated the production of extracellular polymeric substances (EPS), with GAOs having a higher amount of EPS than PAOs. Overall, sulfide had a stronger inhibitory effect on PAOs, giving GAOs a competitive advantage in EBPR when sulfide was present.
JOURNAL OF HAZARDOUS MATERIALS
(2023)
Article
Engineering, Environmental
P. Y. Nguyen, Ricardo Marques, Hongmin Wang, Maria A. M. Reis, Gilda Carvalho, Adrian Oehmen
Summary: Members of the genus Tetrasphaera, potential polyphosphate accumulating organisms (PAOs), have been found to be more abundant than Accumulibacter in full-scale enhanced biological phosphorus removal (EBPR) wastewater treatment plants worldwide. Previous studies have primarily focused on the response of Accumulibacter to pH changes, while this study examines the effect of pH on a Tetrasphaera PAO enriched culture. The results show that pH has a significant impact on the P release and uptake kinetics of PAOs and that high pH levels can benefit the performance of EBPR.
Article
Cell Biology
Bohan Liu, Jun Nan, Xuehui Zu, Xinhui Zhang, Qiliang Xiao
Summary: The study introduced a support vector machine algorithm to achieve rapid identification and prediction of PAOs using bioinformatics data, demonstrating high accuracy and stability.
FRONTIERS IN CELL AND DEVELOPMENTAL BIOLOGY
(2021)
Article
Environmental Sciences
Jun Yin, Kristopher A. Hunt, Ting Xie, Bao Nguyen Quoc, Kim Tran, David A. Stahl, Mari-Karoliina H. Winkler
Summary: Coupling denitrifying polyphosphate accumulating organisms (DPAO) with anaerobic ammonium oxidizing (Anammox) bacteria in a single treatment scheme has challenges due to their competition for nitrite and different growth rates. This study aimed to uncouple their solid retention time (SRT) by growing them in different sludge fractions and found that Anammox bacteria had higher nitrite affinity in biofilms, while DPAO were more sensitive to nitrite and better suited for growth in the protective biofilm.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Ecology
Francesca Petriglieri, Caitlin Singleton, Miriam Peces, Jette F. Petersen, Marta Nierychlo, Per H. Nielsen
Summary: Members of the genus Dechloromonas play a significant role in enhanced biological phosphorus removal systems, with the potential for polyphosphate accumulation. Seven distinct Dechloromonas species were identified in different Danish EBPR plants, each capable of accumulating polyphosphate, glycogen, and polyhydroxyalkanoates.
Article
Engineering, Environmental
Bohan Chen, Yong Li, Zhizhan Luo, Mengen Lei, Xiaolei Zhang, Ji Li
Summary: This study reveals the important role of denitrifying glycogen-accumulating organisms (DGAOs) in sludge granulation, which can help wastewater treatment plants (WWTPs) formulate specific operation strategies to promote the extent of sludge granulation.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Engineering, Environmental
Abdul M. Maszenan, Irina Bessarab, Rohan B. H. Williams, Steve Petrovski, Robert J. Seviour
Summary: This comprehensive review critically evaluates the knowledge about members of the Defluviicoccus genus in wastewater treatment plants, examining their functionality, phylogeny, physiology, and biochemistry. It addresses the controversies and problems in the literature, and discusses the importance of future research in this field.
Review
Agricultural Engineering
Min Ni, Yang Pan, Dapeng Li, Yong Huang, Zhiqiang Chen, Lu Li, Zuowei Song, Yimeng Zhao
Summary: This study assessed the impact of operating conditions of a biofilm sequencing batch reactor (BSBR) on the community structure and metabolic pathways of polyphosphate-accumulating organisms (PAOs). The findings suggest significant differences compared to the enhanced biological phosphorus removal (EBPR) process. The PAOs in BSBR have various metabolic pathways to ensure efficient energy circulation and show distinct differences from the classic mechanism based on Candidatus_Accumulibacter and Tetrasphaera.
BIORESOURCE TECHNOLOGY
(2022)
Article
Environmental Sciences
Li Wang, Adrian Oehmen, Chencheng Le, Jianbo Liu, Yan Zhou
Summary: The study found that at high temperatures, glycogen-accumulating organisms are less competitive in anaerobic VFA uptake compared to polyphosphate-accumulating organisms, contrary to previous observations. Different types of glycogen-accumulating organisms also exhibit differences in competitiveness in anaerobic VFA uptake.
Article
Environmental Sciences
Bin Zhao, Yanping Yang, Chen Zhao, Chunchun Zhang, Zhaohui Zhang, Liang Wang, Shang Wang, Jingfeng Wang
Summary: This study investigates the metabolic mechanisms of glycogen accumulating organisms (GAOs) and reveals the crucial metabolic pathways in a GAOs enrichment system. It also provides insights into the potential application of Ca. Contendobacter for wastewater treatment.
JOURNAL OF ENVIRONMENTAL SCIENCES
(2023)
Article
Engineering, Environmental
Jing Zhao, Tao Liu, Jia Meng, Zhetai Hu, Xuanyu Lu, Shihu Hu, Zhiguo Yuan, Min Zheng
Summary: The significance of residual ammonium concentration to the mainstream PN/A biofilm system was systematically investigated. The study found that a residual NH4+ concentration of -50 mg N/L was essential to stable nitrite-oxidizing bacteria (NOB) suppression, while a lower concentration of -5 mg N/L caused NOB proliferation. High NH4+ concentration promoted the activity of ammonia oxidizing bacteria (AOB) and reduced oxygen penetration depth. These findings provide important knowledge for process control and expand the understanding of microbial interactions in mainstream PN/A biofilm systems.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Engineering, Environmental
Xi Lu, Zhiyao Wang, Haoran Duan, Ziping Wu, Shihu Hu, Liu Ye, Zhiguo Yuan, Min Zheng
Summary: The study investigated the production and pathways of nitric oxide (NO) and nitrous oxide (N2O) during acidic sludge digestion. It was found that a significant amount of total nitrogen (TN) was lost, with 40% emitted as NO and 8% as N2O. Batch assays revealed that nitrite reduction and endogenous microbial activities played a role in this process.
Article
Microbiology
Simon J. J. McIlroy, Andy O. O. Leu, Xueqin Zhang, Rhys Newell, Ben J. J. Woodcroft, Zhiguo Yuan, Shihu Hu, Gene W. W. Tyson
Summary: In this study, a bio-reactor dominated by 'Candidatus Methanoperedens nitroreducens' was characterized using meta-omics and fluorescence in situ hybridization (FISH). Unexpectedly, two morphotypes of 'Ca. M. nitroreducens', coccobacilli microcolonies and planktonic rods, were found to stably co-exist. Genomically identical but distinct in gene expression profiles for carbon metabolism, motility, and cell division were observed in these morphotypes. Additionally, a third phenotype that stored carbon as polyhydroxyalkanoates was observed in some coccobacilli 'Ca. M. nitroreducens'. The phenotypic variation of 'Ca. M. nitroreducens' likely aids their survival and dispersal in sub-optimal environmental conditions.
NATURE MICROBIOLOGY
(2023)
Review
Chemistry, Physical
Jamin C. Wood, Zhiguo Yuan, Bernardino Virdis
Summary: A circular carbon economy can decouple production from fossil fuels, but strategies are needed to maximize decarbonization in the short term. Electrochemical processes offer opportunities to link renewable electricity with chemical production, but currently only a few chemical products have reached commercialization stages. By using commercialized electro-chemical products, such as hydrogen and carbon monoxide, as feedstocks, higher overall energy efficiencies can be achieved in producing other platform chemicals. This approach is being recognized in the industry, with several companies leading the way.
CURRENT OPINION IN ELECTROCHEMISTRY
(2023)
Review
Materials Science, Multidisciplinary
Yizhu Kuang, Hesamoddin Rabiee, Lei Ge, Thomas E. Rufford, Zhiguo Yuan, John Bell, Hao Wang
Summary: This paper provides an overview of recent strategies for highly concentrated formic acid/formate products in electrochemical CO2 reduction reaction (CO2RR). Novel electrolyzers and design of planar and gas diffusion electrodes are introduced as engineering strategies to improve the concentration of formic acid/formate and reduce the cost of downstream separations. The existing technological challenges are highlighted, and recommendations for further research are provided.
ENERGY & ENVIRONMENTAL MATERIALS
(2023)
Article
Agricultural Engineering
Liang Zhang, Xiuping Wang, Yun Chen, Baorui Zhang, Hui Xu, Chenchen Li, Yan Zhou
Summary: In this study, the production of medium-chain fatty acids (MCFA) from mixed sludge without additional electron donors (EDs) was investigated. The anaerobic fermentation of mixed sludge without thermal hydrolysis process (THP) pretreatment generated 0.5 g COD/L of MCFAs with the in situ generated ethanol serving as the EDs. The addition of ethanol improved MCFA yield and caproiciproducens was the dominant chain-elongating bacteria.
BIORESOURCE TECHNOLOGY
(2023)
Article
Engineering, Environmental
Tao Liu, Shihu Hu, Zhiguo Yuan, Jianhua Guo
Summary: The spatial distribution of microorganisms in a methane-based membrane biofilm reactor (MBfR) was experimentally revealed in this study, showing the dominance of anammox bacteria, nitrite/nitrate-dependent anaerobic methane oxidation (n-DAMO) bacteria, and n-DAMO archaea in different layers of the biofilm. It was found that microorganisms in the outer layer preferred substrates from wastewater, while those in the inner layer utilized substrates from the biofilm substratum. This study provides insights into microbial stratification in biofilm systems and potential applications of methane-based MBfRs in sewage treatment.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Article
Engineering, Environmental
Zhetai Hu, Shihu Hu, Liu Ye, Haoran Duan, Ziping Wu, Pei-Ying Hong, Zhiguo Yuan, Min Zheng
Summary: This study presents a new technology roadmap for wastewater management, focusing on resource recovery rather than pollutant removal. A novel use of FeCl3 in an integrated anaerobic wastewater treatment and anammox process was developed, showing stable suppression of nitrite-oxidizing bacteria and excess sludge reduction. Experimental assessments using a laboratory-scale system demonstrated good effluent quality, with potential for phosphorus recovery and bioenergy production. The system was found to have low energy consumption and a net energy production of about 0.11 kWh/m3-wastewater.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Article
Engineering, Environmental
Zhuan Khai Lim, Tao Liu, Min Zheng, Maxime Rattier, Jurg Keller, Zhiguo Yuan, Jianhua Guo, Shihu Hu
Summary: Anaerobic membrane bioreactor (AnMBR) with membrane reciprocation as fouling control method showed a higher energy recovery and more energy-efficient performance compared to conventional biogas sparging in treating domestic wastewater. The carbon balance calculation and energy evaluation demonstrated that membrane reciprocation consumed 62% less energy (0.59 kWh/m3) than biogas sparging (1.56 kWh/m3) at the same operational conditions. With high biogas recovery and energy-efficient fouling control, a positive net energy balance (0.55-0.74 kWh/m3) was achieved, indicating the potential of AnMBR with membrane reciprocation as an energy-positive A-stage in domestic sewage treatment.
RESOURCES CONSERVATION AND RECYCLING
(2023)
Article
Environmental Sciences
Pengfei Zhang, Yan Zhou, Xinlei Pan, Junguo He, Xiang Zou, Yijie Zhong, Jie Zhang, Qiupeng Cai
Summary: In this study, the combination of lysozyme and sodium citrate pretreatment was used to stabilize aluminum and enhance the production of VFAs in anaerobic fermentation of aluminum-rich waste activated sludge (WAS). The results showed that citrate efficiently complexed and stabilized aluminum, alleviating its inhibition on lysozymes and other extracellular hydro lases. The lysozyme, protease, and alpha-glucosidase activities increased by 1.86, 1.72, and 1.15 times, respectively, after the pretreatment. The total VFAs produced from the Al-rich WAS after six-day anaerobic fermentation following the lysozyme and sodium citrate pretreatment were 7.3 times higher than the control group. This study presents a novel approach to enhance VFA production in anaerobic fermentation and mitigate the risk of aluminum pollution from aluminum-rich WAS.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Environmental Sciences
Zhetai Hu, Shihu Hu, Pei-Ying Hong, Xueqin Zhang, Veljko Prodanovic, Kefeng Zhang, Liu Ye, Ana Deletic, Zhiguo Yuan, Min Zheng
Summary: Anaerobic treatment of domestic wastewater has advantages over conventional aerobic treatment in terms of lower biomass yield, lower energy demand and higher energy recovery. However, it faces issues of excessive phosphate and sulfide in effluent, as well as excess H2S and CO2 in biogas. This study proposes an electrochemical method that generates Fe2+ in the anode and hydroxide ion (OH-) and H2 in the cathode to overcome these challenges. The results show that dosing of the electrochemically generated iron significantly improves the performance of anaerobic wastewater treatment, increasing COD removal efficiency, CH4 production rate, dissolved sulfide reduction, and phosphate removal efficiency, while upgrading the quality of biogas by reducing CO2 and H2S contents.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Environmental Sciences
Veljko Prodanovic, Kefeng Zhang, Min Zheng, Shihu Hu, Pei-Ying Hong, Zhiguo Yuan, Ana Deletic
Summary: Vegetated biofiltration systems are widely used for urban stormwater and greywater treatment, but the impact of high ammonium strength wastewater on nitrification process is not well understood. A laboratory-based column study was conducted to investigate dominant nitrification mechanisms. The results showed that appropriate aerobic contact time, oxygenation and alkalinity buffering are necessary for effective nitrification.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Environmental Sciences
Yi-Kun Geng, Jun Gu, Xiaoyuan Zhang, Zhuan Khai Lim, Yishuai Jiang, Meng Zhang, Yan Zhou, Yu Liu
Summary: This study developed an innovative A-B process for carbon-neutral wastewater treatment by combining an anaerobic biofilm reactor (AnBR) as the A stage for energy recovery and a step-feed membrane bioreactor (MBR) as the B stage for mainstream deammonification. A multi-parameter control-based operation strategy was developed to address the challenge of selectively retaining ammonia-oxidizing bacteria (AOB) over nitrite oxidizing bacteria (NOB). Results showed that this process configuration achieved high removal rates of COD, ammonium-N, and total nitrogen, while promoting the growth and enrichment of anammox bacteria.
Article
Environmental Sciences
Mayra Rodriguez, Guangtao Fu, David Butler, Zhiguo Yuan, Lauren Cook
Summary: This study presents a top-down method to quantify resilience performance in combined sewer systems (CSS) by expanding the existing Global Resilience Analysis. It establishes a link between threats and impacts through continuous and long-term simulation, and introduces eight new metrics to assess CSO discharge impacts. A case study in Fehraltorf, Switzerland demonstrates that green infrastructure enhances CSS resilience, with green roofs being the most effective type and the downstream outfall displaying the highest resilience enhancement. This approach provides a standardized approach for resilience assessment and informs the development of strategies for CSO discharge reduction and CSS resilience enhancement.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2023)
Article
Environmental Sciences
Rui Wang, Zijing An, Lu Fan, Yan Zhou, Xiaomei Su, Junjie Zhu, Qian Zhang, Chongjun Chen, Hongjun Lin, Faqian Sun
Summary: Quorum quenching (QQ) is a novel technique for controlling biofouling in membrane bioreactors (MBRs) by disrupting quorum sensing (QS) and inhibiting biofilm formation. This study evaluated the effectiveness of the QQ strain Brucella sp. ZJ1, encapsulated in alginate beads, in mitigating biofouling. The results showed that MBR with QQ beads extended operation time by 2-3 times without affecting pollutant degradation, and these beads maintained approximately 50% QQ activity even after 50 days of operation.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2023)
Article
Engineering, Environmental
Rong-Gui Zhu, Chang-Gui Pan, Feng-Jiao Peng, Chao-Yang Zhou, Jun-Jie Hu, Kefu Yu
Summary: This comprehensive survey investigated the occurrence, bioaccumulation, and trophic magnification of parabens and their metabolite 4-HB in a marine food web. Results showed that parabens were the predominant pollutants in marine organisms, with significant bioaccumulation from sediments. The estimated trophic magnification factor indicated biomagnification for MeP and trophic dilution for 4-HB. Overall, the risks for humans consuming marine organisms were found to be low.
Article
Engineering, Environmental
Andres F. Torres-Franco, Deborah Leroy-Freitas, Cristina Martinez-Fraile, Elisa Rodriguez, Pedro A. Garcia-Encina, Raul Munoz
Summary: Anaerobic and microalgae-based technologies have emerged as sustainable alternatives for municipal wastewater treatment. However, the presence of viruses in the treated wastewater is a major concern for reuse applications. This study assessed the ability of these technologies to reduce viruses during secondary wastewater treatment. The results showed that all technologies were effective in reducing the concentration of viruses, with microalgae-based treatment exhibiting the highest potential for reducing the disinfection requirements of treated wastewater.
Article
Engineering, Environmental
Young Gwang Kim, Sae Yun Kwon, Spencer J. Washburn, Scott C. Brooks, Ji Won Yoon, Lucien Besnard
Summary: The study uses Hg isotope ratios to identify the sources and exposure pathways of mercury in bivalves, finding that dissolved Hg phases in the water column are the primary source and exposure pathway to bivalves. This provides new insights into using bivalves as bioindicators for sediment quality monitoring.
Article
Engineering, Environmental
Hui Geng, Ying Xu, Rui Liu, Dianhai Yang, Xiaohu Dai
Summary: This study investigates the effect of cation exchange resin (CER) on the sequential recovery of hydrogen and methane from anaerobic digestion (AD) and the corresponding mechanisms. The results show that CER can simultaneously enhance the production of hydrogen and methane by promoting the solubilisation, hydrolysis, and acidification of organic matter. Additionally, CER facilitates effective contact between bacteria and organic particulates and reduces the energy barrier for mass transfer during methane production. The study also reveals changes in the microbial community structure and metagenomics during the AD process.
Article
Engineering, Environmental
Xiaojing Lin, Zhan Jin, Shunfeng Jiang, Zhiquan Wang, Suqing Wu, Ke Bei, Min Zhao, Xiangyong Zheng
Summary: Dehumidification combined with addition of absorbent resin supplement (ARS) was used to achieve rapid evaporation of non-pretreated urine, resulting in high water evaporation efficiency and nutrient recovery.
Article
Engineering, Environmental
Yangli Che, Chaoran Lin, Shen Li, Jiao Liu, Longhai Zhu, Shilei Yu, Nan Wang, Haoshuai Li, Mutai Bao, Yang Zhou, Tonghao Si, Rui Bao
Summary: Hydrodynamic processes play a crucial role in the transmission of sediments, microbial assembly, and organic carbon redistribution in the ocean. Through experiments and analysis, we found that hydrodynamics shape the assembly of microbial communities and control the redistribution of different sourced organic carbon, thereby influencing microbial-mediated biogeochemical transformation.
Article
Engineering, Environmental
Chao Chen, Yu Yang, Nigel J. D. Graham, Zhenyu Li, Xingtao Yang, Zhining Wang, Nadia Farhat, Johannes S. Vrouwenvelder, Li -an Hou
Summary: The fouling of seawater reverse osmosis membranes is a persistent challenge in desalination. This study monitored the operational performance of a desalination plant for 7 years and the fouling development in different areas of membrane modules. The findings showed that operational performance declined over time and fouling mainly occurred at the feed side of the modules, with the highest microbial diversity. Keystone species like Chloroflexi and Planctomycetes played an important role in maintaining community structure and biofilm maturation. Polysaccharides, soluble microbial products, marine humic acid-like substances, and inorganic substances contributed to fouling. Overall, biofouling had a significant impact on membrane fouling after 7 years of operation.
Article
Engineering, Environmental
Dan Li, Jieyi Sun, Yibo Fu, Wentao Hong, Heli Wang, Qian Yang, Junhong Wu, Sen Yang, Jianhui Xu, Yunfei Zhang, Yirong Deng, Yin Zhong, Ping'an Peng
Summary: Sulfidation-oxidation treatment of magnetite (Fe3O4) enhances the production of dark center dot OH, which can efficiently degrade dissolved organic matter (DOM) and accelerate carbon cycling.
Article
Engineering, Environmental
Cheng Yu, Kaijun Wang, Kaiyuan Zhang, Ruiyang Liu, Pingping Zheng
Summary: This study implemented a microaerobic-aerobic configuration in a full-scale municipal wastewater treatment facility and investigated the effects on sludge characteristics, pollutant removal, microbial community, and granulation mechanisms. The results showed successful transition from flocculent-activated sludge to well-defined AGS after two months of operation. The primary pathways for pollutant removal were simultaneous nitrification, denitrification, and phosphorus removal. Moreover, the incorporation of internal separators induced shifts in the flow pattern, which promoted granulation.
Article
Engineering, Environmental
Zhe Zhang, Shaoyang Hu, Guangrong Sun, Wei Wang
Summary: Halogenated aromatic disinfection byproducts (DBPs), such as halogenated phenols, have garnered widespread attention due to their high toxicity and prevalence. This study reports on the analysis, occurrence, and cytotoxicity of a group of emerging halogenated aromatic DBPs, known as halogenated polyhydroxyphenols (HPPs), in drinking water.
Article
Engineering, Environmental
Shengyue Chen, Jinliang Huang, Peng Wang, Xi Tang, Zhenyu Zhang
Summary: Accurate prediction of river water quality is crucial for sustainable water management. This study introduces wavelet analysis and transfer learning techniques to assist LSTM modeling, proposing a newly coupled modeling approach that improves short-term prediction of river water quality.
Article
Engineering, Environmental
Bang Du, Xinmin Zhan, Piet N. L. Lens, Yifeng Zhang, Guangxue Wu
Summary: Efficient anaerobic digestion relies on the cooperation of different microorganisms with different metabolic pathways. This study investigated the effects of different operational modes and the addition of powdered activated carbon (PAC) on ethanol metabolic pathways. The results showed that the SBR mode and the presence of CO2 facilitated ethanol metabolism towards propionate production, while the CFR mode with extended solids retention time enriched Geobacter. Adjusting operational modes and PAC addition can modulate anaerobic ethanol metabolism and enrich Geobacter.
Article
Engineering, Environmental
Wanfa Wang, Si-Liang Li, Jun Zhong, Yuanbi Yi, Fujun Yue, Zenglei Han, Qixin Wu, Ding He, Cong-Qiang Liu
Summary: This study compares the carbon biogeochemical processes in karst and non-karst regions within large thermal stratified river-reservoir systems. The results demonstrate that karst reservoirs have a reduced potential for carbon emissions and highlight the importance of considering geologic settings to improve accuracy in regional and global CO2 emission estimates.
Article
Engineering, Environmental
Chunxia Jiang, Zelong Zhao, Dong Zhu, Xiong Pan, Yuyi Yang
Summary: This study analyzed the occurrence and distribution of antibiotic resistance genes (ARGs) in different environmental media of the Yangtze River using metagenomics. Core resistome dominated by multidrug resistance genes was found in all samples, while rare resistome dominated by various resistance genes was more prevalent in plasmids. Specific bacteria were identified as hosts for both core and rare resistomes, with high clinical concern ARGs found in the rare resistome. Particle-associated environment provided the most ideal conditions for resistome hosts. This study provided insights into the genetic locations of ARGs and the community assembly mechanisms of ARG hosts in freshwater environments.
Article
Engineering, Environmental
Yu Zhang, Yongtao He, Linchun Jia, Lei Xu, Zheng Wang, Yueling He, Ling Xiong, Xumeng Lin, Hong Chen, Gang Xue
Summary: By synergizing organic carbon source, thiosulfate, and zero-valent iron, efficient mixotrophic denitrification of oligotrophic secondary effluent can be achieved. Thiosulfate plays a vital role in promoting TN removal efficiency, while corrosion of Fe0 releases OH- to neutralize H+ from thiosulfate-driven denitrification, creating a suitable environment for denitrification. The coordination of thiosulfate and Fe0 maintains the dominance of Thiobacillus for denitrification.