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Cheng J, Robles-Lecompte A, McKenna AM, Chang NB. Deciphering linkages between DON and the microbial community for nitrogen removal using two green sorption media in a surface water filtration system. CHEMOSPHERE 2024; 357:142042. [PMID: 38621490 DOI: 10.1016/j.chemosphere.2024.142042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Revised: 04/11/2024] [Accepted: 04/12/2024] [Indexed: 04/17/2024]
Abstract
The presence of dissolved organic nitrogen (DON) in stormwater treatment processes is a continuous challenge because of the intertwined nature of its decomposition, bioavailability, and biodegradability and its unclear molecular characteristics. In this paper, 21 T Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) in combination with quantitative polymerase chain reaction was applied to elucidate the molecular change of DON and microbial population dynamics in a field-scale water filtration system filled with two specialty adsorbents for comparison in South Florida where the dry and wet seasons are distinctive annually. The adsorbents included CPS (clay-perlite and sand sorption media) and ZIPGEM (zero-valent iron and perlite-based green environmental media). Our study revealed that seasonal effects can significantly influence the dynamic characteristics and biodegradability of DON. The microbial population density in the filter beds indicated that three microbial species in the nitrogen cycle were particularly thrived for denitrification, dissimilatory nitrate reduction to ammonium, and anaerobic ammonium oxidation via competition and commensalism relationships during the wet season. Also, there was a decrease in the compositional complexity and molecular weight of the DON groups (CnHmOpN1, CnHmOpN2, CnHmOpN3, and CnHmOpN4), revealed by the 21 T FT-ICR MS bioassay, driven by a microbial population quantified by polymerase chain reaction from the dry to the wet season. These findings indirectly corroborate the assumption that the metabolism of microorganisms is much more vigorous in the wet season. The results affirm that the sustainable materials (CPS and ZIPGEM) can sustain nitrogen removal intermittently by providing a suitable living environment in which the metabolism of microbial species can be cultivated and enhanced to facilitate physico-chemical nitrogen removal across the two types of green sorption media.
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Affiliation(s)
- Jinxiang Cheng
- Department of Civil, Environmental, and Construction Engineering, University of Central Florida, Orlando, FL, USA
| | - Alejandra Robles-Lecompte
- Department of Civil, Environmental, and Construction Engineering, University of Central Florida, Orlando, FL, USA
| | - Amy M McKenna
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL, USA; Department of Soil and Crop Sciences, Colorado State University, Fort Collins, CO, USA
| | - Ni-Bin Chang
- Department of Civil, Environmental, and Construction Engineering, University of Central Florida, Orlando, FL, USA.
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2
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Cheng Y, Lu C, Gao S, Koju R, Li H, Zhu Z, Hu C, Qu J. Synchronous in-situ sludge reduction and enhanced denitrification through improving electron transfer during endogenous metabolisms with Fe(Ⅱ) addition. WATER RESEARCH 2024; 255:121472. [PMID: 38552492 DOI: 10.1016/j.watres.2024.121472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 02/10/2024] [Accepted: 03/13/2024] [Indexed: 04/24/2024]
Abstract
The creation of large amounts of excess sludge and residual nitrogen are critical issues in wastewater biotreatment. This study introduced Fe(II) into an oligotrophic anaerobic reactor (OARFe) that was implemented to modify an anoxic-oxic process to motivate in-situ sludge reduction and enhance denitrification under an effective electron shuttle among organic matter, nitrogen, and Fe. The addition of 15 mg L-1 Fe(II) resulted in a sludge reduction efficiency reached 32.0% with a decreased effluent nitrate concentration of 33.3%. This was mostly attributed to the electron transfer from Fe(II) to organic matters and nitrogen species in OARFe. The participation of Fe(II) led to the upregulation of Geothrix and Terrimonas, which caused active organic matter hydrolysis and cell lysis to stimulate the release of extracellular polymeric substances (EPS) and substance transfer between each layer of EPS. The higher utilization of released bioavailable dissolved organic matter improved endogenous denitrification, which can be combined with iron autotrophic denitrification to realize multiple electron donor-based nitrogen removal pathways, resulting in an increased nitrate removal rate of 58.2% in the absence of external carbon sources. These functional bacteria associated with the transformation of nitrogen and carbon and cycling between ferrous and ferric ions were enriched in OARFe, which contributed to efficient electron transport occurred both inside and outside the cell and increased 2,3,5-triphenyltetrazolium chloride electronic transport system activity by 46.9%. This contributed to the potential operational costs of chemical addition and sludge disposal of Fe-AO being 1.9 times lower than those of conventional A2O processes. These results imply that the addition of ferrous ions to an oligotrophic anaerobic zone for wastewater treatment has the potential for low-cost pollution control.
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Affiliation(s)
- Yu Cheng
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing 100083, China; Centre for Urban Environmental Remediation, Beijing University of Civil Engineering and Architecture, Beijing 102616, China
| | - Chenghai Lu
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shujia Gao
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; College of Environmental Science and Engineering, Guilin University of Technology, Jiangan Road 12, Guilin, Guangxi 541004, China
| | - Rashmi Koju
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Haiyan Li
- Centre for Urban Environmental Remediation, Beijing University of Civil Engineering and Architecture, Beijing 102616, China
| | - Zongqiang Zhu
- College of Environmental Science and Engineering, Guilin University of Technology, Jiangan Road 12, Guilin, Guangxi 541004, China.
| | - Chengzhi Hu
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Jiuhui Qu
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
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3
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Lv X, Zhang W, Deng J, Feng S, Zhan H. Pyrite and humus soil-coupled mixotrophic denitrification system for efficient nitrate and phosphate removal. ENVIRONMENTAL RESEARCH 2024; 247:118105. [PMID: 38224940 DOI: 10.1016/j.envres.2024.118105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2023] [Revised: 12/23/2023] [Accepted: 01/02/2024] [Indexed: 01/17/2024]
Affiliation(s)
- Xin Lv
- Inner Mongolia Research Institute, School of Chemical & Environmental Engineering, China University of Mining & Technology (Beijing), Beijing, 100083, China
| | - Wenxi Zhang
- Inner Mongolia Research Institute, School of Chemical & Environmental Engineering, China University of Mining & Technology (Beijing), Beijing, 100083, China
| | - Jiushuai Deng
- Inner Mongolia Research Institute, School of Chemical & Environmental Engineering, China University of Mining & Technology (Beijing), Beijing, 100083, China; Engineering Technology Research Center for Comprehensive Utilization of Rare Earth, Rare Metal and Rare-Scattered in Non-ferrous Metal Industry, CUMTB, Beijing, 100083, China; Key Laboratory of Separation and Processing of Symbiotic-Associated Mineral Resources in Non-ferrous Metal Industry, CUMTB, Beijing, 100083, China.
| | - Shengyuan Feng
- Jiangxi Gaiya Environm Sci & Technol Co. Ltd, Shangrao, Jiangxi, 334000, China
| | - Hongzhi Zhan
- Jiangxi Gaiya Environm Sci & Technol Co. Ltd, Shangrao, Jiangxi, 334000, China
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Fang Y, Chen C, Cui B, Zhou D. Nanoscale zero-valent iron alleviate antibiotic resistance risk during managed aquifer recharge (MAR) by regulating denitrifying bacterial network. JOURNAL OF HAZARDOUS MATERIALS 2024; 465:133238. [PMID: 38134694 DOI: 10.1016/j.jhazmat.2023.133238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 11/05/2023] [Accepted: 12/10/2023] [Indexed: 12/24/2023]
Abstract
The frequent occurrence of antibiotics in reclaimed water is concerning, in the case of managed aquifer recharge (MAR), it inevitably hinders further water purification and accelerates the evolutionary resistance in indigenous bacteria. In this study, we constructed two column reactors and nanoscale zero-valent iron (nZVI) amendment was applied for its effects on water quality variation, microbial community succession, and antibiotic resistance genes (ARGs) dissemination, deciphered the underlying mechanism of resistance risk reduction. Results showed that nZVI was oxidized to iron oxides in the sediment column, and total effluent iron concentration was within permissible limits. nZVI enhanced NO3--N removal by 15.5% through enriching denitrifying bacteria and genes, whereas made no effects on oxacillin (OXA) removal. In addition, nZVI exhibited a pivotal impact on ARGs and plasmids decreasing. Network analysis elucidated that the diversity and richness of ARG host declined with nZVI amendment. Denitrifying bacteria play a key role in suppressing horizontal gene transfer (HGT). The underlying mechanisms of inhibited HGT included the downregulated SOS response, the inhibited Type-Ⅳ secretion system and the weakened driving force. This study afforded vital insights into ARG spread control, providing a reference for future applications of nZVI in MAR.
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Affiliation(s)
- Yuanping Fang
- Engineering Research Center of Low-Carbon Treatment and Green Development of Polluted Water in Northeast China, Ministry of Education, Northeast Normal University, Changchun 130117, China; Jilin Engineering Lab for Water Pollution Control and Resources Recovery, Northeast Normal University, Changchun 130117, China
| | - Congli Chen
- Engineering Research Center of Low-Carbon Treatment and Green Development of Polluted Water in Northeast China, Ministry of Education, Northeast Normal University, Changchun 130117, China; Jilin Engineering Lab for Water Pollution Control and Resources Recovery, Northeast Normal University, Changchun 130117, China
| | - Bin Cui
- Engineering Research Center of Low-Carbon Treatment and Green Development of Polluted Water in Northeast China, Ministry of Education, Northeast Normal University, Changchun 130117, China; Jilin Engineering Lab for Water Pollution Control and Resources Recovery, Northeast Normal University, Changchun 130117, China.
| | - Dandan Zhou
- Engineering Research Center of Low-Carbon Treatment and Green Development of Polluted Water in Northeast China, Ministry of Education, Northeast Normal University, Changchun 130117, China; Jilin Engineering Lab for Water Pollution Control and Resources Recovery, Northeast Normal University, Changchun 130117, China.
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Anggraini TM, An S, Chung J, Kim EJ, Kwon MJ, Kim SH, Lee S. Synergetic effect of nitrate on dissolved organic carbon attenuation through dissimilatory iron reduction during aquifer storage and recovery. WATER RESEARCH 2024; 249:120954. [PMID: 38064781 DOI: 10.1016/j.watres.2023.120954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 11/22/2023] [Accepted: 11/29/2023] [Indexed: 01/03/2024]
Abstract
Aquifer storage and recovery (ASR) is a promising water management technique in terms of quantity and quality. During ASR, iron (Fe) (hydr)oxides contained in the aquifer play a crucial role as electron acceptors in attenuating dissolved organic carbon (DOC) in recharging water through dissimilatory iron reduction (DIR). Considering the preference of electron acceptors, nitrate (NO3⁻), possibly coexisting with DOC as the prior electron acceptor to Fe (hydr)oxides, might influence DIR by interrupting electron transfer. However, this phenomenon is yet to be clarified. In this study, we systematically investigated the potential effect of NO3⁻ on DOC attenuation during ASR using a series of sediment columns representing typical aquifer conditions. The results suggest that DOC attenuation could be enhanced by the presence of NO3⁻. Specifically, total DOC attenuation was notably higher than that from the stoichiometric calculation simply employing NO3⁻ as the additional electron acceptor to Fe (hydr)oxides, implying a synergetic effect of NO3⁻ in the overall reactions. X-ray photoelectron spectroscopy analyzes revealed that the Fe(II) ions released from DIR transformed the Fe (hydr)oxides into a less bioavailable form, inhibiting further DIR. In the presence of NO3⁻, however, no aqueous Fe(II) was detected, and another form of Fe (hydr)oxide appeared on the sediment surface. This may be attributed to nitrate-dependent Fe(II) oxidation (NDFO), in which Fe(II) is (re)oxidized into Fe (hydr)oxide, which is available for the subsequent DOC attenuation. These mechanisms were supported by the dominance of DIR-relevant bacteria and the growth of NDFO-related bacteria in the presence of NO3⁻.
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Affiliation(s)
- Theresia May Anggraini
- Water Cycle Research Center, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea; Division of Energy and Environment Technology, KIST School, Korea University of Science and Technology, Seoul 02792, Republic of Korea
| | - Seongnam An
- Water Cycle Research Center, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea
| | - Jaeshik Chung
- Water Cycle Research Center, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea; Division of Energy and Environment Technology, KIST School, Korea University of Science and Technology, Seoul 02792, Republic of Korea
| | - Eun-Ju Kim
- Water Cycle Research Center, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea; Division of Energy and Environment Technology, KIST School, Korea University of Science and Technology, Seoul 02792, Republic of Korea
| | - Man Jae Kwon
- Department of Earth and Environmental Sciences, Korea University, Seoul 02841, Republic of Korea
| | - Sang Hyun Kim
- Water Cycle Research Center, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea; Division of Energy and Environment Technology, KIST School, Korea University of Science and Technology, Seoul 02792, Republic of Korea.
| | - Seunghak Lee
- Water Cycle Research Center, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea; Division of Energy and Environment Technology, KIST School, Korea University of Science and Technology, Seoul 02792, Republic of Korea; Graduate School of Energy and Environment (KU-KIST GREEN SCHOOL), Korea University, Seoul 02841, Republic of Korea.
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Chen J, Ma S, Wang H, Wang Y, Ren H, Xu K. Weak magnetic carriers reduce nitrite accumulation and boost denitrification at high nitrate concentrations by enriching functional bacteria and enhancing electron transfer. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 351:119734. [PMID: 38071915 DOI: 10.1016/j.jenvman.2023.119734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Revised: 11/19/2023] [Accepted: 11/26/2023] [Indexed: 01/14/2024]
Abstract
Biological denitrification is the dominant method for NO3- removal from wastewater, while high NO3- leads to NO2- accumulation and inhibits denitrification performance. In this study, different weak magnetic carriers (0, 0.3, 0.6, 0.9 mT) were used to enhance biological denitrification at NO3- of 50-2400 mg/L. The effect of magnetic carriers on the removal and mechanism of denitrification of high NO3- was investigated. The results showed that 0.6 and 0.9 mT carriers significantly enhanced the TN removal efficiency (>99%) and reduced the accumulation of NO2- (by > 97%) at NO3- of 1200-2400 mg/L 0.6 and 0.9 mT carriers stimulated microbial electron transport by improving the abundances of coenzyme Q-cytochrome C reductase (by 4.44-23.30%) and cytochrome C (by 2.90-16.77%), which contributed to the enhanced elimination of NO3- and NO2-. 0.6 and 0.9 mT carriers increased the activities of NAR (by 3.74-37.59%) and NIR (by 5.01-8.24%). The abundance of narG genes in 0.6 and 0.9 mT was 1.47-2.35 and 1.38-1.75 times that of R1, respectively, and the abundance of nirS genes was 1.49-2.83 and 1.55-2.39 times that of R1, respectively. Denitrifying microorganisms, e.g., Halomonas, Thauera and Pseudomonas were enriched at 0.6 and 0.9 mT carriers, which benefited to the advanced denitrification performance. This study suggests that weak magnetic carriers can help to enhance the biological denitrification of high NO3- wastewater.
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Affiliation(s)
- Jiahui Chen
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, Jiangsu, PR China
| | - Sijia Ma
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, Jiangsu, PR China
| | - Haiyue Wang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, Jiangsu, PR China
| | - Yanru Wang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, Jiangsu, PR China
| | - Hongqiang Ren
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, Jiangsu, PR China
| | - Ke Xu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, Jiangsu, PR China.
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Liu Y, Xu L, Su J, Ali A, Huang T, Wang Y, Zhang P. Microbially driven Fe-N cycle: Intrinsic mechanisms, enhancement, and perspectives. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 908:168084. [PMID: 37924885 DOI: 10.1016/j.scitotenv.2023.168084] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 10/21/2023] [Accepted: 10/21/2023] [Indexed: 11/06/2023]
Abstract
The iron‑nitrogen (FeN) cycle driven by microbes has great potential for treating wastewater. Fe is a metal that is frequently present in the environment and one of the crucial trace elements needed by microbes. Due to its synergistic role in the microbial N removal process, Fe goes much beyond the essential nutritional needs of microorganisms. Investigating the mechanisms behind the linked Fe-N cycle driven by microbes is crucial. The Fe-N cycle is frequently connected with anaerobic ammonia oxidation (anammox), nitrification, denitrification, dissimilatory nitrate reduction to ammonium (DNRA), Feammox, and simultaneous nitrification denitrification (SND), etc. Although the main mechanisms of Fe-mediated biological N removal may vary depending on the valence state of the Fe, their similar transformation pathways may provide information on the study of certain element-microbial interactions. This review offers a thorough analysis of the facilitation effect and influence of Fe on the removal of nitrogenous pollutants in various biological N removal processes and summarizes the ideal Fe dosing. Additionally, the synergistic mechanisms of Fe and microbial synergistic N removal process are elaborated, covering four aspects: enzyme activity, electron transfer, microbial extracellular polymeric substances (EPS) secretion, and microbial community interactions. The methods to improve biological N removal based on the intrinsic mechanism were also discussed, with the aim of thoroughly understanding the biological mechanisms of Fe in the microbial N removal process and providing a reference and thinking for employing Fe to promote microbial N removal in practical applications.
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Affiliation(s)
- Yan Liu
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Liang Xu
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Junfeng Su
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
| | - Amjad Ali
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Tinglin Huang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Yue Wang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Peng Zhang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
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8
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Gong S, Cai Q, Hong P, Cai P, Xiao B, Wang C, Wu X, Tian C. Promoting heterotrophic denitrification of Pseudomonas hunanensis strain PAD-1 using pyrite: A mechanistic study. ENVIRONMENTAL RESEARCH 2023; 234:116591. [PMID: 37423367 DOI: 10.1016/j.envres.2023.116591] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2023] [Revised: 06/26/2023] [Accepted: 07/06/2023] [Indexed: 07/11/2023]
Abstract
Denitrification is critical for removing nitrate from wastewater, but it typically requires large amounts of organic carbon, which can lead to high operating costs and secondary environmental pollution. To address this issue, this study proposes a novel method to reduce the demand for organic carbon in denitrification. In this study, a new denitrifier, Pseudomonas hunanensis strain PAD-1, was obtained with properties for high efficiency nitrogen removal and trace N2O emission. It was also used to explore the feasibility of pyrite-enhanced denitrification to reduce organic carbon demand. The results showed that pyrite significantly improved the heterotrophic denitrification of strain PAD-1, and optimal addition amount was 0.8-1.6 g/L. The strengthening effect of pyrite was positively correlated with carbon to nitrogen ratio, and it could effectively reduce demand for organic carbon sources and enhance carbon metabolism of strain PAD-1. Meanwhile, the pyrite significantly up-regulated electron transport system activity (ETSA) of strain PAD-1 by 80%, nitrate reductase activity by 16%, Complex III activity by 28%, and napA expression by 5.21 times. Overall, the addition of pyrite presents a new avenue for reducing carbon source demand and improving the nitrate harmless rate in the nitrogen removal process.
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Affiliation(s)
- Shihao Gong
- Key Laboratory of Algal Biology of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China; Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, 100872, Hong Kong
| | - Qijia Cai
- Key Laboratory of Algal Biology of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Pei Hong
- School of Ecology and Environment, Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang Basin Co-founded By Anhui Province and Ministry of Education, Anhui Normal University, Wuhu, 241002, China
| | - Pei Cai
- Key Laboratory of Algal Biology of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Bangding Xiao
- Key Laboratory of Algal Biology of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China; Dianchi Lake Ecosystem Observation and Research Station of Yunnan Province, Kunming, 650228, China
| | - Chunbo Wang
- Key Laboratory of Algal Biology of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China; Dianchi Lake Ecosystem Observation and Research Station of Yunnan Province, Kunming, 650228, China
| | - Xingqiang Wu
- Key Laboratory of Algal Biology of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China; Dianchi Lake Ecosystem Observation and Research Station of Yunnan Province, Kunming, 650228, China
| | - Cuicui Tian
- Key Laboratory of Algal Biology of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China; Dianchi Lake Ecosystem Observation and Research Station of Yunnan Province, Kunming, 650228, China.
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9
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Yu L, Zhang E, Yang L, Liu S, Rensing C, Zhou S. Combining biological denitrification and electricity generation in methane-powered microbial fuel cells. J Environ Sci (China) 2023; 130:212-222. [PMID: 37032037 DOI: 10.1016/j.jes.2022.10.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 10/10/2022] [Accepted: 10/11/2022] [Indexed: 06/19/2023]
Abstract
Methane has been demonstrated to be a feasible substrate for electricity generation in microbial fuel cells (MFCs) and denitrifying anaerobic methane oxidation (DAMO). However, these two processes were evaluated separately in previous studies and it has remained unknown whether methane is able to simultaneously drive these processes. Here we investigated the co-occurrence and performance of these two processes in the anodic chamber of MFCs. The results showed that methane successfully fueled both electrogenesis and denitrification. Importantly, the maximum nitrate removal rate was significantly enhanced from (1.4 ± 0.8) to (18.4 ± 1.2) mg N/(L·day) by an electrogenic process. In the presence of DAMO, the MFCs achieved a maximum voltage of 610 mV and a maximum power density of 143 ± 12 mW/m2. Electrochemical analyses demonstrated that some redox substances (e.g. riboflavin) were likely involved in electrogenesis and also in the denitrification process. High-throughput sequencing indicated that the methanogen Methanobacterium, a close relative of Methanobacterium espanolae, catalyzed methane oxidation and cooperated with both exoelectrogens and denitrifiers (e.g., Azoarcus). This work provides an effective strategy for improving DAMO in methane-powered MFCs, and suggests that methanogens and denitrifiers may jointly be able to provide an alternative to archaeal DAMO for methane-dependent denitrification.
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Affiliation(s)
- Linpeng Yu
- Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Eryi Zhang
- Cranfield University, Cranfield, Bedfordshire MK43 0AL, UK; Biofuels Institute, School of Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013, China
| | - Lin Yang
- Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Shiqi Liu
- Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Christopher Rensing
- Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Shungui Zhou
- Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
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10
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Kang D, Lee H, Bae H, Jeon J. Comparative insight of pesticide transformations between river and wetland systems. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 879:163172. [PMID: 37003314 DOI: 10.1016/j.scitotenv.2023.163172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 03/18/2023] [Accepted: 03/26/2023] [Indexed: 05/17/2023]
Abstract
The widespread use of pesticides threatens the environment and ecosystems. Despite the positive effects of plant protection products, pesticides also have unexpected negative effects on nontarget organisms. The microbial biodegradation of pesticides is one of the major pathways for reducing their risks at aquatic ecosystems. The objective of this study was to compare the biodegradability of pesticides in simulated wetland and river systems. Parallel experiments were conducted with 17 pesticides based on the OECD 309 guidelines. A comprehensive analytical method, such as target screening combined with suspect and non-target screening, was performed to evaluate the biodegradation via identification of transformation products (TPs) using LC-HRMS. As evidence of biodegradation, we identified 97 TPs for 15 pesticides. Metolachlor and dimethenamid had 23 and 16 TPs, respectively, including Phase II glutathione conjugates. The analysis of 16S rRNA sequences for microbials characterized operational taxonomic units. Rheinheimera and Flavobacterium, which have the potential for glutathione S-transferase, were dominant in wetland systems. Estimation of toxicity, biodegradability, and hydrophobicity using QSAR prediction indicated lower environmental risks of detected TPs. We conclude that the wetland system is more favorable for pesticide degradation and risk mitigation mainly attributed to the abundance and variety of the microbial communities.
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Affiliation(s)
- Daeho Kang
- Department of Environmental Engineering, Changwon National University, Changwon, Gyeongsangnamdo 51140, Republic of Korea
| | - Hyebin Lee
- Graduate School of Carbon Neutrality, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan 44919, Republic of Korea
| | - Hyokwan Bae
- Graduate School of Carbon Neutrality, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan 44919, Republic of Korea; Department of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan 44919, Republic of Korea
| | - Junho Jeon
- Department of Environmental Engineering, Changwon National University, Changwon, Gyeongsangnamdo 51140, Republic of Korea; School of Smart and Green Engineering, Changwon National University, Changwon, Gyeongsangnamdo 51140, Republic of Korea.
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11
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Lyu Z, Liu W, Chi Z. Enhanced nitrate removal using in situ reactive zone with reduced graphene oxide supported nanoscale zero-valent iron. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:53605-53615. [PMID: 36862295 DOI: 10.1007/s11356-023-26147-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Accepted: 02/22/2023] [Indexed: 06/18/2023]
Abstract
Nitrate pollution in groundwater is becoming more serious, which is harmful to human health. The reduced graphene oxide supported nanoscale zero-valent iron (nZVI/rGO) composite prepared in this paper can effectively remove nitrate in groundwater. In situ remediation of nitrate-contaminated aquifer was also studied. The results showed that NH4+-N was the main product of NO3--N reduction, and N2 and NH3 were also produced. When the dosage of rGO/nZVI was more than 0.2 g/L, there was no accumulation of intermediate NO2--N during the reaction process. NO3--N was removed by rGO/nZVI mainly through physical adsorption and reduction process with the maximum adsorbing ability of 37.44 mg NO3--N/g. After the slurry of rGO/nZVI was injected into the aquifer, a stable reaction zone could be formed. NO3--N could be removed continuously within 96 h at the simulated tank, and NH4+-N and NO2--N were as the main reduction products. Moreover, the concentration of TFe near the injection well increased rapidly after rGO/nZVI injection, and could be detected at the downstream end, indicating that the reaction range was large enough for NO3--N removal.
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Affiliation(s)
- Zhibo Lyu
- Key Lab of Groundwater Resources and Environment, Ministry of Education, Jilin University, Changchun, 130021, People's Republic of China
| | - Wanting Liu
- Key Lab of Groundwater Resources and Environment, Ministry of Education, Jilin University, Changchun, 130021, People's Republic of China
| | - Zifang Chi
- Key Lab of Groundwater Resources and Environment, Ministry of Education, Jilin University, Changchun, 130021, People's Republic of China.
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12
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Kong F, Wang J, Hou W, Cui Y, Yu L, Zhang Y, Wang S. Influence of modified biochar supported sulfidation of nano-zero-valent-iron (S-nZVI/BC) on nitrate removal and greenhouse gas emission in constructed wetland. J Environ Sci (China) 2023; 125:568-581. [PMID: 36375939 DOI: 10.1016/j.jes.2022.02.040] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Revised: 02/22/2022] [Accepted: 02/22/2022] [Indexed: 06/16/2023]
Abstract
In this study, the biochar (BC) produced from sawdust, sludge, reed and walnut were used to support sulfidation of nano-zero-valent-iron (S-nZVI) to enhance nitrate (NO3--N) removal and investigate the impact on greenhouse gas emissions. Batch experiment results showed the S-nZVI/BCsawdust (2:1, 500), S-nZVI/BCsludge (2:1, 900), S-nZVI/BCreed (2:1, 700), and S-nZVI/BC walnut (2:1, 700) respectively improved NO3--N removal efficiencies by 22%, 20%, 3% and 0.1%, and the selectivity toward N2 by 22%, 25%, 22% and 18%. S-nZVI uniformly loaded on BC provided electrons for the conversion of NO3--N to N2 through Fe0. At the same time, FeSx layer was formed on the outer layer of ZVI in the sulfidation process to prevent iron oxidation, so as to improve the electrons utilization efficiency After adding four kinds of S-nZVI/BC into constructed wetlands (CWs), the NO3--N removal efficiencies could reach 100% and the N2O emission fluxes were reduced by 24.17%-36.63%. And the average removal efficiencies of TN, COD, TP were increased by 21.9%, -16.5%, 44.3%, repectively. The increasing relative abundances of denitrifying bacteria, such as Comamonas and Simplicispira, suggested that S-nZVI/BC could also improve the process of microbial denitrification. In addition, different S-nZVI/BC had different effects on denitrification functional genes (narG, nirk, nirS and nosZ genes), methanotrophs (pmoA) and methanogenesis (mcrA). This research provided an effective method to improve NO3--N removal and reduce N2O emission in CWs.
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Affiliation(s)
- Fanlong Kong
- College of Environmental Science and Engineering, Qingdao University, Qingdao 266071, China
| | - Junru Wang
- College of Environmental Science and Engineering, Qingdao University, Qingdao 266071, China
| | - Weihao Hou
- College of Environmental Science and Engineering, Qingdao University, Qingdao 266071, China
| | - Yuqian Cui
- College of Environmental Science and Engineering, Qingdao University, Qingdao 266071, China
| | - Lihua Yu
- Qingdao Environmental Protection Bureau, Laixi Branch, Qingdao 266699, China
| | - Yi Zhang
- College of Environmental Science and Engineering, Qingdao University, Qingdao 266071, China
| | - Sen Wang
- College of Environmental Science and Engineering, Qingdao University, Qingdao 266071, China.
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13
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Jia Z, Wang J, Liu X, Yan Z, Bai X, Zhou X, He X, Hou J. Sediment diffusion is feasible to simultaneously reduce nitrate discharge from recirculating aquaculture system and ammonium release from sediments in receiving intensive aquaculture pond. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 858:160017. [PMID: 36370792 DOI: 10.1016/j.scitotenv.2022.160017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 11/02/2022] [Accepted: 11/03/2022] [Indexed: 06/16/2023]
Abstract
Nitrogen accumulation has become one of the greatest unresolved challenges restricting the development of aquaculture worldwide. In recirculating aquaculture system (RAS), lack of organic matter (OM) and sensitive organisms makes it difficult to apply efficient denitrifying technology, thus leading to a high nitrate‑nitrogen (NO3--N) accumulation. In contrast, excess OM accumulation in intensive aquaculture pond sediments is associated with dissolved oxygen depletion and ammonium‑nitrogen (NH4+-N) accumulation in the sediments. Based on the opposing effects of OM on the nitrogen accumulation in RAS and intensive aquaculture ponds, this study assessed the feasibility of simultaneously reducing NO3--N discharge from RAS and controlling NH4+-N accumulation in intensive aquaculture ponds by in situ diffusing RAS tailwater containing NO3--N into intensive aquaculture pond sediments. The results showed that NO3--N diffusion strategy improved the native sediment denitrification capacity, thus increasing NO3--N removal efficiency from RAS tailwater and significantly decreasing the NH4+-N concentration in interstitial water and the total organic carbon content in intensive aquaculture pond sediments. High-throughput sequencing and quantitative real-time polymerase chain reaction (qPCR) results revealed that NO3--N addition significantly increased both nitrifying bacteria and denitrifying bacteria abundance. These results implied that NO3--N diffusion strategy could effectively stimulate microbial decomposition of OM, thus relieving the hypoxia limitation of sediment nitrification. Overall, this study offers a feasible method for simultaneous reduction of NO3--N from RAS tailwater and NH4+-N in intensive aquaculture ponds with low cost and high efficiency.
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Affiliation(s)
- Zhiming Jia
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China
| | - Jie Wang
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China
| | - Xueyu Liu
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China
| | - Zuting Yan
- State key laboratory of Freshwater Ecology and Biotechnology, Key Laboratory of Algal Biology, Institute of Hydrobiology, the Chinese Academy of Sciences, Wuhan 430072, China
| | - Xuelan Bai
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China
| | - Xiaodi Zhou
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China
| | - Xugang He
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China; Engineering Research Center of Green Development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt, Ministry of Education, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan 430070, China.
| | - Jie Hou
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China; Engineering Research Center of Green Development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt, Ministry of Education, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan 430070, China.
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14
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Bi Z, Zhang Q, Xu X, Yuan Y, Ren N, Lee DJ, Chen C. Perspective on inorganic electron donor-mediated biological denitrification process for low C/N wastewaters. BIORESOURCE TECHNOLOGY 2022; 363:127890. [PMID: 36075347 DOI: 10.1016/j.biortech.2022.127890] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 08/28/2022] [Accepted: 08/29/2022] [Indexed: 06/15/2023]
Abstract
Nitrate is the most common water environmental pollutant in the world. Inorganic electron donor-mediated denitrification is a typical process with significant advantages in treating low carbon-nitrogen ratio water and wastewater and has attracted extensive research attention. This review summarizes the denitrification processes using inorganic substances, including hydrogen, reductive sulfur compounds, zero-valent iron, and iron oxides, ammonium nitrogen, and other reductive heavy metal ions as electron donors. Aspects on the functional microorganisms, critical metabolic pathways, limiting factors and mathematical modeling are outlined. Also, the typical inorganic electron donor-mediated denitrification processes and their mechanism, the available microorganisms, process enhancing approaches and the engineering potentials, are compared and discussed. Finally, the prospects of developing the next generation inorganic electron donor-mediated denitrification process is put forward.
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Affiliation(s)
- Zhihao Bi
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang Province 150090, China
| | - Quan Zhang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang Province 150090, China
| | - Xijun Xu
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang Province 150090, China
| | - Yuan Yuan
- College of Biological Engineering, Beijing Polytechnic, Beijing 10076, China
| | - Nanqi Ren
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang Province 150090, China; Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen 518055, China
| | - Duu-Jong Lee
- Department of Mechanical Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong; Department of Chemical Engineering and Materials Science, Yuan Ze University, Chung-li 32003, Taiwan
| | - Chuan Chen
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang Province 150090, China.
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15
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Wang Z, Su J, Ali A, Sun Y, Li Y, Yang W, Zhang R. Enhanced removal of fluoride, nitrate, and calcium using self-assembled fungus-flexible fiber composite microspheres combined with microbially induced calcium precipitation. CHEMOSPHERE 2022; 302:134848. [PMID: 35526689 DOI: 10.1016/j.chemosphere.2022.134848] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Revised: 04/26/2022] [Accepted: 05/02/2022] [Indexed: 06/14/2023]
Abstract
Self-assembled fungus-flexible fiber composite microspheres (SFFMs) were firstly combined with microbially induced calcium precipitation (MICP) in a continuous-flow bioreactor and achieved the efficient removal of fluoride (F-), nitrate (NO3-), and calcium (Ca2+). Under the influent F- of 3.0 mg L-1, pH of 7.0, and HRT of 8 h, the average removal efficiencies reached 77.54%, 99.39%, and 67.25% (0.29, 2.03, and 8.34 mg L-1 h-1), respectively. Fluorescence spectrum and flow cytometry analyses indicated that F- content significantly affected the metabolism and viability of bacteria. SEM images showed that flexible fibers and intertwined hyphae provided effective locations for bacterial colonization in SFFMs. The precipitated products were characterized by XRD and FTIR, which revealed that F- was mainly removed in the form of calcium fluoride and calcium fluorophosphate (CaF2 and Ca5(PO4)3F). High-throughput analysis at different levels demonstrated that Pseudomonas sp. WZ39 acted as the core strain, which played a crucial role in the bioreactor. The mechanism of enhanced denitrification was attributed to minor F- stress and bioaugmentation technology. This study highlighted the superiorities of SFFMs and MICP combined remediation and documented a promising option for F-, NO3-, and Ca2+ removal.
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Affiliation(s)
- Zhao Wang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China
| | - Junfeng Su
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China.
| | - Amjad Ali
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China
| | - Yi Sun
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China
| | - Yifei Li
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China
| | - Wenshuo Yang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China
| | - Ruijie Zhang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China
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16
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Sun Y, Gu Y, Xiao S. Adsorption behaviors and mechanisms of Al-Fe dual-decorated biochar adsorbent for phosphate removal from rural wastewater. J DISPER SCI TECHNOL 2022. [DOI: 10.1080/01932691.2022.2102035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Affiliation(s)
- Yue Sun
- Department of Municipal Engineering, School of Civil Engineering, Southeast University, Nanjing, China
| | - Yingpeng Gu
- Department of Municipal Engineering, School of Civil Engineering, Southeast University, Nanjing, China
| | - Shuying Xiao
- Department of Municipal Engineering, School of Civil Engineering, Southeast University, Nanjing, China
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17
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Diagnostic Method for Enhancing Nitrogen and Phosphorus Removal in Cyclic Activated Sludge Technology (CAST) Process Wastewater Treatment Plant. WATER 2022. [DOI: 10.3390/w14142253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Ensuring the stable operation of urban wastewater treatment plants (WWTPs) and achieving energy conservation and emission reduction have become serious problems with the improvement of national requirements for WWTP effluent. Based on a wastewater quality analysis, identification of the contaminant removal, and a simulation and optimization of the wastewater treatment process, a practical engineering diagnosis method for the cyclic activated sludge technology process of WWTPs in China and an optimal control scheme are proposed in this study. Results showed that exceeding the standard of effluent nitrogen and phosphorus due to unreasonable process cycle setting and insufficient influent carbon source is dangerous. The total nitrogen removal rate increased by 9.5% and steadily increased to 67% when agitation was added to the first 40 min of the cycle. Additionally, the total phosphorus (TP) was reduced to 0.27 mg/L after replacing the phosphorus removal agent polyferric sulfate with polyaluminum iron. The corresponding increase in the TP removal rate to 97% resulted in a reduction in the treatment cost by 0.008 CNY/t.
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