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Wang Y, Gao Y, Wang X, Lin Y, Xu G, Yang F, Ni K. Insights into the phage community structure and potential function in silage fermentation. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 358:120837. [PMID: 38593737 DOI: 10.1016/j.jenvman.2024.120837] [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: 02/01/2024] [Revised: 04/01/2024] [Accepted: 04/01/2024] [Indexed: 04/11/2024]
Abstract
The virus that infects bacteria known as phage, plays a crucial role in the biogeochemical cycling of nutrients. However, the community structure and potential functions of phages in silage fermentation remain largely unexplored. In this study, we utilized viral metagenomics (viromics) to investigate the types, lifestyles, functions, and nutrient utilization patterns of phages in silage. Our findings indicated a high prevalence of annotated phages belonging to Caudovirales and Geplafuvirales, as well as unclassified phages in silage. The predominant host types for these phages were Campylobacterales and Enterobacterales. Virulent phages dominated the silage environment due to their broader range of hosts and enhanced survival capabilities. All identified phages present in silage were found to be non-pathogenic. Although temperate and virulent phages carried distinct genes associated with nutrient cycling processes, the shared genes (prsA) involved in carbon metabolism underscore the potential significance of phages in regulating carbon metabolism in silage. Overall, our findings provide a valuable foundation for further exploring the complex interactions between phages and microorganisms in regulating silage fermentation quality.
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Affiliation(s)
- Yuan Wang
- College of Grassland Science and Technology, China Agricultural University, Beijing, 100193, PR China
| | - Yu Gao
- College of Grassland Science and Technology, China Agricultural University, Beijing, 100193, PR China
| | - Xin Wang
- College of Grassland Science and Technology, China Agricultural University, Beijing, 100193, PR China
| | - Yanli Lin
- College of Grassland Science and Technology, China Agricultural University, Beijing, 100193, PR China
| | - Gang Xu
- College of Grassland Science and Technology, China Agricultural University, Beijing, 100193, PR China
| | - Fuyu Yang
- College of Grassland Science and Technology, China Agricultural University, Beijing, 100193, PR China; College of Animal Science, Guizhou University, Guiyang, 550025, PR China.
| | - Kuikui Ni
- College of Grassland Science and Technology, China Agricultural University, Beijing, 100193, PR China.
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An Z, Gao X, Shao B, Zhang Q, Ding J, Peng Y. Synchronous Achievement of Advanced Nitrogen Removal and N 2O Reduction in the Anoxic Zone in the AOA Process for Low C/N Municipal Wastewater. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:2335-2345. [PMID: 38271692 DOI: 10.1021/acs.est.3c06746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2024]
Abstract
Continuous flow processes for the in situ determination of N2O emissions during low C/N municipal wastewater treatment have rarely been reported. The anaerobic/aerobic/anoxic (AOA) process has recently shown promising potential in energy savings and advanced nitrogen removal, but it still needs to be comprehensively explored in relation to N2O emissions for its carbon reduction advantages. In this study, a novel gas-collecting continuous flow reactor was designed to comprehensively evaluate the emissions of N2O from the gas and liquid phases of the AOA process. Additionally, the measures of enhancing endogenous denitrification (ED) and self-enriching anaerobic ammonium oxidation (Anammox) were employed to optimize nitrogen removal and achieve N2O reduction in the anoxic zone. The results showed that enhanced ED coupled with Anammox led to an increase in the nitrogen removal efficiency (NRE) from 67.65 to 81.96%, an enhancement of the NO3- removal rate from 1.76 mgN/(L h) to 3.99 mgN/(L h), and the N2O emission factor in the anoxic zone decreased from 0.28 to 0.06%. Impressively, ED eliminated 91.46 ± 2.47% of the dissolved N2O from the upstream aerobic zone, and the dissolved N2O in the effluent was reduced to less than 0.01 mg/L. This study provides valuable strategies for fully evaluating N2O emissions and N2O reduction from the AOA process.
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Affiliation(s)
- Zeming An
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, PR China
| | - Xinjie Gao
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, PR China
| | - Baishuo Shao
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, PR China
| | - Qiong Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, PR China
| | - Jing Ding
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, PR China
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, PR China
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3
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Chen T, Deng C, Wu Z, Liu T, Zhang Y, Xu X, Zhao X, Li J, Li S, Xu N, Yu K. Metagenomic analysis unveils the underexplored roles of prokaryotic viruses in a full-scale landfill leachate treatment plant. WATER RESEARCH 2023; 245:120611. [PMID: 37722141 DOI: 10.1016/j.watres.2023.120611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 09/06/2023] [Accepted: 09/09/2023] [Indexed: 09/20/2023]
Abstract
Enormous viral populations have been identified in activated sludge systems, but their ecological and biochemical roles in landfill leachate treatment plants remain poorly understood. To address this knowledge gap, we conducted an in-depth analysis using 36 metagenomic datasets that we collected and sequenced during a half-year time-series sampling campaign at six sites in a full-scale landfill leachate treatment plant (LLTP), elucidating viral distribution, virus‒host dynamics, virus-encoded auxiliary metabolic genes (AMGs), and viral contributions to the spread of virulence and antibiotic resistance genes. Our findings demonstrated that viral and prokaryotic communities differed widely among different treatment units, with stability over time. LLTP viruses were linked to various prokaryotic hosts, spanning 35 bacterial phyla and one archaeal phylum, which included the core microbes involved in biological treatments, as well as some of the less well-characterized microbial dark matter phyla. By encoding 2364 auxiliary metabolic genes (AMGs), viruses harbored the potential to regulate microbial nucleotide metabolism, facilitate the biodegradation of complex organic matter, and enhance flocculation and settling in biological treatment plants. The abundance distribution of AMGs varied considerably across treatment units and showed a lifestyle-dependent pattern with temperate virus-associated AMGs exhibiting a higher average abundance in downstream biological treatment units and effluent water. Meanwhile, temperate viruses tended to carry a higher load of virulence factor genes (VFGs), antibiotic resistance genes (ARGs), and biotic and metal resistance genes (BMRGs), and engaged in more frequent gene exchanges with prokaryotes than lytic viruses, thus acting as a pivotal contributor to the dissemination of pathogenicity and resistance genes in downstream LLTP units. This study provided a comprehensive profile of viral and prokaryotic communities in the LLTP and unveiled the varying roles of different-lifestyle viruses in biochemical processes and water quality safety.
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Affiliation(s)
- Tianyi Chen
- Eco-environment and Resource Efficiency Research Laboratory, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China; Environmental Microbiome and Innovative Genomics Laboratory, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Chunfang Deng
- Eco-environment and Resource Efficiency Research Laboratory, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China; Environmental Microbiome and Innovative Genomics Laboratory, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China.
| | - Zongzhi Wu
- Environmental Microbiome and Innovative Genomics Laboratory, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Tang Liu
- Environmental Microbiome Engineering and Innovative Genomics Laboratory, College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, China
| | - Yuanyan Zhang
- Jiangxi Academy of Eco-Environmental Sciences & Planning, Nanchang 330029, China
| | - Xuming Xu
- Department of Water Ecology and Environment, China Institute of Water Resources and Hydropower Research, Beijing 100038, China
| | - Xiaohui Zhao
- Environmental Microbiome and Innovative Genomics Laboratory, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Jiarui Li
- Environmental Microbiome and Innovative Genomics Laboratory, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Shaoyang Li
- Eco-environment and Resource Efficiency Research Laboratory, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Nan Xu
- Eco-environment and Resource Efficiency Research Laboratory, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Ke Yu
- Eco-environment and Resource Efficiency Research Laboratory, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
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Yan L, Yin M, Jiao Y, Zheng Y, Sun L, Yang M, Miao J, Song X, Sun N. The presence of copper ions alters tetracycline removal pathway in aerobic granular sludge: Performance and mechanism. BIORESOURCE TECHNOLOGY 2023; 385:129446. [PMID: 37399954 DOI: 10.1016/j.biortech.2023.129446] [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: 05/31/2023] [Revised: 06/29/2023] [Accepted: 06/30/2023] [Indexed: 07/05/2023]
Abstract
This study investigated the removal characteristics of tetracycline (TC) in the presence of copper ions (Cu2+) in aerobic granular sludge by analyzing the TC removal pathway, composition and functional group changes of extracellular polymeric substances (EPS), and microbial community structure. The TC removal pathway changed from cell biosorption to EPS biosorption, and the microbial degradation rate of TC was reduced by 21.37% in the presence of Cu2+. Cu2+ and TC induced enrichment of denitrifying bacteria and EPS-producing bacteria by regulating the expression of signaling molecules and amino acid synthesis genes to increase the content of EPS and -NH2 groups in EPS. Although Cu2+ reduced the content of acidic hydroxyl functional groups (AHFG) in EPS, an increase in TC concentration stimulated the secretion of more AHFG and -NH2 groups in EPS. The long-term presence of TC presence of the relative abundances of Thauera, Flavobacterium and Rhodobacter and improved the removal efficiency.
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Affiliation(s)
- Lilong Yan
- College of Resource and Environment, Northeast Agricultural University, Harbin 150030 China.
| | - Mingyue Yin
- College of Resource and Environment, Northeast Agricultural University, Harbin 150030 China
| | - Yue Jiao
- College of Resource and Environment, Northeast Agricultural University, Harbin 150030 China
| | - Yaoqi Zheng
- College of Resource and Environment, Northeast Agricultural University, Harbin 150030 China
| | - Luotinng Sun
- College of Resource and Environment, Northeast Agricultural University, Harbin 150030 China
| | - Mengya Yang
- College of Resource and Environment, Northeast Agricultural University, Harbin 150030 China
| | - Jingwen Miao
- College of Resource and Environment, Northeast Agricultural University, Harbin 150030 China
| | - Xu Song
- College of Resource and Environment, Northeast Agricultural University, Harbin 150030 China
| | - Nan Sun
- College of Water Conservancy and Civil Engineering, Northeast Agricultural University, Harbin 150030 China
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5
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Fan Y, Sun S, He S. Iron plaque formation and its effect on key elements cycling in constructed wetlands: Functions and outlooks. WATER RESEARCH 2023; 235:119837. [PMID: 36905735 DOI: 10.1016/j.watres.2023.119837] [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: 11/14/2022] [Revised: 02/13/2023] [Accepted: 03/05/2023] [Indexed: 06/18/2023]
Abstract
Ecological restoration of wetland plants has emerged as an environmentally-friendly and less carbon footprint method for treating secondary effluent wastewater. Root iron plaque (IP) is located at the important ecological niches in constructed wetlands (CWs) ecosystem and is the critical micro-zone for pollutants migration and transformation. Root IP can affect the chemical behaviors and bioavailability of key elements (C, N, P) since its formation/dissolution is a dynamic equilibrium process jointly influenced by rhizosphere habitats. However, as an efficient approach to further explore the mechanism of pollutant removal in CWs, the dynamic formation of root IP and its function have not been fully studied, especially in substrate-enhanced CWs. This article concentrates on the biogeochemical processes between Fe cycling involved in root IP with carbon turnover, nitrogen transformation, and phosphorus availability in CWs rhizosphere. As IP has the potential to enhance pollutant removal by being regulated and managed, we summarized the critical factors affecting the IP formation from the perspective of wetland design and operation, as well as emphasizing the heterogeneity of rhizosphere redox and the role of key microbes in nutrient cycling. Subsequently, interactions between redox-controlled root IP and biogeochemical elements (C, N, P) are emphatically discussed. Additionally, the effects of IP on emerging contaminants and heavy metals in CWs rhizosphere are assessed. Finally, major challenges and outlooks for future research in regards to root IP are proposed. It is expected that this review can provide a new perspective for the efficient removal of target pollutants in CWs.
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Affiliation(s)
- Yuanyuan Fan
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Shanshan Sun
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Shengbing He
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China; Shanghai Engineering Research Center of Landscape Water Environment, Shanghai 200031, China.
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Huang L, Bao J, Zhao F, Liang Y, Chen Y. New insight for purifying polluted river water using the combination of large-scale rotating biological contactors and integrated constructed wetlands in the cold season. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 324:116433. [PMID: 36352732 DOI: 10.1016/j.jenvman.2022.116433] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 09/19/2022] [Accepted: 10/02/2022] [Indexed: 06/16/2023]
Abstract
Ecological treatment technologies, applied to deal with polluted river water in the low temperature season, remain limited. In this study, a new insight was put forward for purifying polluted river water using a combination system (CS) of large-scale rotating biological contactors (RBCs) and integrated constructed wetlands in autumn and winter. The treatment performance, average removal contribution (RC), nitrification and denitrification rates, microbial community structure, and ecosystem service value were considered to estimate the combination system. Results revealed that the average removal efficiencies of ammonium (NH4+-N), total nitrogen (TN), total phosphorus (TP), and chemical oxygen demand (COD) reached 93.9%, 20.8%, 36.5%, and 37.1%, respectively. The combination system showed excellent removal efficiency of NH4+-N regardless of the effect of low temperature. The maximum values of nitrification and denitrification rates were 59.57 g N/(m3·d) and 0.78 g N/(m2·d), respectively. Considerable differences in bacterial community diversity, richness and relative abundance of functional microbes were observed in the main treatment units, resulting in different average RC to pollutants. The unit capital cost of CS purifying polluted river water was 260 USD/m3 and the operation and maintenance cost was 0.144 million USD/yr. Meanwhile, the ecosystem service value of the CS was 0.334 million USD in autumn and winter. CS not only possessed excellent pollutant purifying efficiencies, but also achieved high ecological service value in the cold season.
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Affiliation(s)
- Lei Huang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment (Ministry of Education), College of Resources and Environment, Southwest University, Chongqing, 400715, China; Chongqing Key Laboratory of Agricultural Resources and Environment, Chongqing, 400716, China.
| | - Jun'an Bao
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment (Ministry of Education), College of Resources and Environment, Southwest University, Chongqing, 400715, China
| | - Fang Zhao
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment (Ministry of Education), College of Resources and Environment, Southwest University, Chongqing, 400715, China
| | - Yinkun Liang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment (Ministry of Education), College of Resources and Environment, Southwest University, Chongqing, 400715, China
| | - Yucheng Chen
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment (Ministry of Education), College of Resources and Environment, Southwest University, Chongqing, 400715, China; Chongqing Key Laboratory of Agricultural Resources and Environment, Chongqing, 400716, China.
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Mao W, Yang R, Shi H, Feng H, Chen S, Wang X. Identification of key water parameters and microbiological compositions triggering intensive N 2O emissions during landfill leachate treatment process. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 833:155135. [PMID: 35405234 DOI: 10.1016/j.scitotenv.2022.155135] [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: 12/15/2021] [Revised: 03/16/2022] [Accepted: 04/05/2022] [Indexed: 06/14/2023]
Abstract
Landfill leachate treatment processes tend to emit more N2O compared to domestic wastewater treatment. This discrepancy may be ascribed to leachate water characteristics such as high refractory COD, ammonium (NH4+) content, and salinity. In this work, the leachate influent was varied to examine the N2O emission scenarios. NH4+-N, COD, and Cl- concentrations ranged between 1000-2500, 1000-10,000, and 500-3000 mg L-1, respectively. Simultaneously, we attempted to combine statistical analysis with high-throughput sequencing to understand the microbial mechanism with regards to N2O emission. Results show that the strong N2O emissions occur in the nitrifying tank due to the intensive aeration. The system receiving the lowest COD shows the maximum N2O emission factor of 42.7% of the removed nitrogen. Both redundancy analysis and a structural equation model verify that insufficient degradable organics are the key water parameter triggering intensive N2O emission within the designed influent limits. Furthermore, two essential but non-abundant functional bacteria, Flavobacterium (acting as a denitrifier) and Nitrosomonas (acting as a nitrifier), are identified as the core functional species that dramatically influence N2O emissions. An increase in influent COD promotes the proliferation of Flavobacterium and inhibits Nitrosomonas, which in turn reduce N2O release. Meanwhile, two keystone species of Castellaniella and Saprospiraceae unclassified are recognized. They may supply a suitable niche and integrity of the microbial community for N-cycle functional bacteria. These findings reveal the essential role of non-abundant species in microbial community, and expand the current understanding of microbial interactions underlying N2O dynamics in leachate treatment systems.
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Affiliation(s)
- Wenlong Mao
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Ruili Yang
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Huiqun Shi
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Hualiang Feng
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
| | - Shaohua Chen
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
| | - Xiaojun Wang
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
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Remmas N, Manfe N, Raga R, Akratos C. Activated sludge microbial communities and hydrolytic potential in a full-scale SBR system treating landfill leachate. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2022; 57:764-772. [PMID: 35946503 DOI: 10.1080/10934529.2022.2110478] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 07/28/2022] [Accepted: 07/31/2022] [Indexed: 06/15/2023]
Abstract
Landfill leachate, due to its recalcitrant nature and toxicity, poses a serious environmental threat, which requires the implementation of effective treatment processes. In this work, a full-scale treatment system consisting of two Sequencing Batch Reactors (SBRs) was used for the processing of landfill leachate of intermediate to mature age (BOD/COD ratio of 0.16). Biosystem operation resulted in BOD5, COD and TKN removal efficiencies of 81%, 39% and 76%, respectively, whereas the low residual NO3--N concentration in the effluent (4.01 ± 0.10 mg/L) was indicative of the efficient denitrification process. Assessment of hydrolytic potential of activated sludge revealed high endocellular and extracellular lipase activities, which reached values up to 206 and 141 U/g protein respectively, possibly as the consequence of plastics degradation during maturation process. Implementation of Illumina sequencing indicated the predominance of Alphaproteobacteria, accompanied by members of Bacteroidetes, Betaproteobacteria and Chloroflexi. Paracoccus was the predominant genus identified, followed by representatives of the genera Bellilinea, Flavobacterium, Thauera and Truepera. Nitrosomonas was the major ammonia-oxidizing bacterium (AOB), while nitrite oxidation was mainly achieved by the uncultured nitrite-oxidizing bacterium (NOB) Candidatus Nitrotoga.
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Affiliation(s)
- Nikolaos Remmas
- Laboratory of Wastewater Management and Treatment Technologies, Department of Environmental Engineering, Democritus University of Thrace, Xanthi, Greece
- Laboratory of Ecological Engineering and Technology, Department of Civil Engineering, Democritus University of Thrace, Xanthi, Greece
| | - Nicola Manfe
- Laboratory of Wastewater Management and Treatment Technologies, Department of Environmental Engineering, Democritus University of Thrace, Xanthi, Greece
- Department of Civil, Environmental and Architectural Engineering, University of Padua, Padua, Italy
| | - Roberto Raga
- Department of Civil, Environmental and Architectural Engineering, University of Padua, Padua, Italy
| | - Christos Akratos
- Laboratory of Ecological Engineering and Technology, Department of Civil Engineering, Democritus University of Thrace, Xanthi, Greece
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Nitrogen Removal from Mature Landfill Leachate via Anammox Based Processes: A Review. SUSTAINABILITY 2022. [DOI: 10.3390/su14020995] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Mature landfill leachate is a complex and highly polluted effluent with a large amount of ammonia nitrogen, toxic components and low biodegradability. Its COD/N and BOD5/COD ratios are low, which is not suitable for traditional nitrification and denitrification processes. Anaerobic ammonia oxidation (anammox) is an innovative biological denitrification process, relying on anammox bacteria to form stable biofilms or granules. It has been extensively used in nitrogen removal of mature landfill leachate due to its high efficiency, low cost and sludge yield. This paper reviewed recent advances of anammox based processes for mature landfill leachate treatment. The state of the art anammox process for mature landfill leachate is systematically described, mainly including partial nitrification–anammox, partial nitrification–anammox coupled denitrification. At the same time, the microbiological analysis of the process operation was given. Anaerobic ammonium oxidation (anammox) has the merit of saving the carbon source and aeration energy, while its practical application is mainly limited by an unstable influent condition, operational control and seasonal temperature variation. To improve process efficiency, it is suggested to develop some novel denitrification processes coupled with anammox to reduce the inhibition of anammox bacteria by mature landfill leachate, and to find cheap new carbon sources (methane, waste fruits) to improve the biological denitrification efficiency of the anammox system.
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Passarini MRZ, Moreira JVF, Gomez JAM, Bonugli-Santos RC. DNA metabarcoding of the leachate microbiota from sanitary landfill: potential for bioremediation process. Arch Microbiol 2021; 203:4847-4858. [PMID: 34228134 DOI: 10.1007/s00203-021-02471-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 06/29/2021] [Accepted: 06/30/2021] [Indexed: 01/04/2023]
Abstract
Leachate generation contains a variety of toxic compounds, and is a major problem for municipal solid waste (MSW). Microbial profile knowledge is essential to new alternatives and improvements in current treatments of these effluents. In this respect, the microbial community in the leachate from the sanitary landfill of the city of Foz do Iguaçu was analyzed. The 16S rDNA metabarcoding suggested the dominance of fermenting bacteria belonging to Firmicutes phylum, followed by Proteobacteria, Bacteroidetes, and Synergistetes. The most abundant genera were Sedimentibacter, Vulcanibacillus, and Anaerovorax. However, 60% of amplicon sequence variants (ASVs) were not classified taxonomically. In addition, an expressive abundance was attributed to the superphylum known as PVC group, little studied and with unknown scientific potential. The leachate acidogenic phase was masked in the chemical and physical analyzes. Nevertheless, it was evidenced in the metabarcoding methodology. No specifically methanogenic group was detected in significant abundance. Therefore, from bacterial community identification, a bioremediation process can be designed. Enriched culture media can be developed and targeted to the recovery of specific groups which may be involved in leachate biodegradation. What is more, the results expand the knowledge of bacterial diversity, especially from the presence of unknown genera in this habitat.
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Affiliation(s)
- Michel Rodrigo Zambrano Passarini
- Institute Latin American of Nature and Life Sciences (ILACNV), Interdisciplinary Center of Life Sciences (CICV), Federal University of Latin American Integration (UNILA), 1000 Tarquínio Joslin dos Santos Av., Jardim Universitário, Foz do Iguaçu, PR, 85870-901, Brazil
| | - João Victor Fonseca Moreira
- Institute Latin American of Nature and Life Sciences (ILACNV), Interdisciplinary Center of Life Sciences (CICV), Federal University of Latin American Integration (UNILA), 1000 Tarquínio Joslin dos Santos Av., Jardim Universitário, Foz do Iguaçu, PR, 85870-901, Brazil
| | - Jose Alejandro Morales Gomez
- Institute Latin American of Nature and Life Sciences (ILACNV), Interdisciplinary Center of Life Sciences (CICV), Federal University of Latin American Integration (UNILA), 1000 Tarquínio Joslin dos Santos Av., Jardim Universitário, Foz do Iguaçu, PR, 85870-901, Brazil
| | - Rafaella Costa Bonugli-Santos
- Institute Latin American of Nature and Life Sciences (ILACNV), Interdisciplinary Center of Life Sciences (CICV), Federal University of Latin American Integration (UNILA), 1000 Tarquínio Joslin dos Santos Av., Jardim Universitário, Foz do Iguaçu, PR, 85870-901, Brazil.
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11
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Su C, Tao AF, Zhao L, Wang P, Wang A, Huang X, Chen M. Roles of modified biochar in the performance, sludge characteristics, and microbial community features of anaerobic reactor for treatment food waste. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 770:144668. [PMID: 33513502 DOI: 10.1016/j.scitotenv.2020.144668] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Revised: 11/16/2020] [Accepted: 12/17/2020] [Indexed: 06/12/2023]
Abstract
Anaerobic digestion (AD) is a green technology widely applied to food waste treatment. Although the AD has high efficiency, instability often occurs. The main purpose of the study is to understand the mechanism of modified biochar improving AD performance. The effects of different modified biochar on the efficiency and microecology of an anaerobic reactor treating food waste were investigated. Bagasse biochar was used as the substrate to explore the effects of iron-modified (A), chitosan-modified (B), iron-chitosan-modified (C) and iron‑magnesium-chitosan-modified (D) biochar on the anaerobic digestion process, sludge characteristics and microbial community. The results show that the average COD removal efficiency of the four reactors during the last five days of the experimentation period was 86.95%, 85.90%, 92.22% and 93.29%, respectively. Adding iron‑magnesium-chitosan-modified biochar could improve the efficiency of COD removal in the anaerobic reactor under ammonia nitrogen stress. On day 10 of operation, the content of coenzyme F420 in the sludge of anaerobic reactors C and D reached to 0.44 and 0.57 mmol/g, respectively, indicating that the metal-chitosan complex biochar could promote the production of coenzyme F420 in the early stage of the experiment. Within the four anaerobic reactors, Firmicutes, Bacteroidetes, Proteobacteria and Chloroflexi were the dominant bacteria, and the abundance of Chloroflexi reached a maximum of 26.24% in the reactor C. As for archaea, Methanobacterium and Methanothrix were the most dominant accounting for 44.03%, 49.88%, 31.29%, 52.01% and 38.34%, 34.52%, 50.9%, 35.72% respectively in the four reactors. KEGG functional analysis showed that the energy metabolism of bacteria and archaea in the reactor D was the largest among the four reactors. Meanwhile, the gene abundance associated with carbohydrate metabolism and membrane transport of microorganisms in the reactor D was greater than that of other groups.
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Affiliation(s)
- Chengyuan Su
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, 15 Yucai Road, Guilin, 541004, PR China; Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology for Science and Education Combined with Science and Technology Innovation Base, 12 Jiangan Road, Guilin, 541004, PR China; University Key Laboratory of Karst Ecology and Environmental Change of Guangxi Province (Guangxi Normal University), 15 Yucai Road, Guilin, 541004, PR China.
| | - AFeng Tao
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, 15 Yucai Road, Guilin, 541004, PR China
| | - Lijian Zhao
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, 15 Yucai Road, Guilin, 541004, PR China
| | - Pengfei Wang
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, 15 Yucai Road, Guilin, 541004, PR China
| | - Anliu Wang
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, 15 Yucai Road, Guilin, 541004, PR China
| | - Xian Huang
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, 15 Yucai Road, Guilin, 541004, PR China
| | - Menglin Chen
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, 15 Yucai Road, Guilin, 541004, PR China
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12
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Scaling-Up and Long-Term Operation of a Full-Scale Two-Stage Partial Nitritation-Anammox System Treating Landfill Leachate. Processes (Basel) 2021. [DOI: 10.3390/pr9050800] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
(1) Background: Biological treatment of leachate in landfill sites using anaerobic ammonium oxidation (anammox) is challenging because of the intrinsic characteristics of this complex wastewater. In this work, the scale-up and subsequent full-scale implementation of the PANAMMOX® technology (LEQUIA Research Group, Girona, Catalonia, Spain) are presented as a case study to achieve long-term nitrogen (N) removal from mature leachate mostly through a completely autotrophic pathway. (2) Methods: The treatment system consists of two sequencing batch reactors (SBRs) running in series to individually operate partial nitritation (PN) and anammox (A). Following biological treatment, physicochemical oxidation (i.e., Fenton-based process) was used to remove the remaining non-biodegradable organic matter. A cost analysis comparative was conducted in relation to the former technology used on-site for treating the leachate. (3) Results: The scale-up of the process from pilot- to full-scale was successfully achieved, finally reaching an average removal of 7.4 kg N/d. The composition of the leachate changed over time, but especially once the landfill site stopped receiving solid waste (this fact involved a marked increase in the strength of the leachate). The adjustment of the alkalinity-to-ammonium ratio before feeding PN-SBR helped to improve the N-removal efficiency. Values of conductivity above 25 mS/cm in A-SBR could negatively affect the performance of the anammox process, making it necessary to consider a dilution strategy according to the on-line monitoring of this parameter. The analysis of the operational costs showed that by implementing the PANAMMOX® technology (LEQUIA Research Group, Girona, Catalonia, Spain) in the landfill site, savings up to 32% were achievable. (4) Conclusions: Treatment of mature landfill leachate in such a two-stage PN-A system was demonstrated as feasible and economically appealing despite the complexity of this industrial wastewater. Accurate expert supervision of the process was a key factor to reaching good performances.
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13
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Isolated heterotrophic nitrifying and aerobic denitrifying bacterium for treating actual refinery wastewater with low C/N ratio. J Biosci Bioeng 2021; 132:41-48. [PMID: 33931317 DOI: 10.1016/j.jbiosc.2021.03.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2020] [Revised: 03/23/2021] [Accepted: 03/23/2021] [Indexed: 11/20/2022]
Abstract
Heterotrophic nitrifying and aerobic denitrifying bacteria that have been widely isolated from complicated activated sludge microflorae demonstrate dominant advantages in simultaneous removal of ammonium and nitrogen oxides under aerobic conditions. However, owing to the need of organic carbon to support bacterial growth, nitrogen removal of actual industrial wastewater with low carbon-to-nitrogen (C/N) ratio remains a challenge. Here, Pseudomonas mendocina Y7 was identified and presented to effectively remove nitrogen of actual refinery wastewater with low C/N ratio. The isolated bacterium showed high removal efficiency of NH4+-N, NO2--N, and NO3--N up to about 90% in single (100 mg/L) or mixed (200 mg/L) nitrogen source media at low C/N ratio of 6 when it was cultivated for 12 or 21 h. According to PCR amplification, the heterotrophic nitrification and aerobic denitrification capability of strain Y7 was attributed to the functional genes of amoA, hao, napA, and nirS. In activated sludge process for treating actual refinery wastewater with low C/N ratio, compared to abundant accumulation of NO2--N and NO3--N only using the activated sludge, strain Y7 significantly improved the removal efficiency of NH4+‒N and total nitrogen (with influent concentrations of about 40 and 55 mg/L) from about 47% and 22% to about 85% and 73%, respectively, without the accumulation of nitrogen oxides. Microbial community structure analysis revealed that strain Y7 could coexist well with other microorganisms in the activated sludge and maintain highly efficient and steady nitrogen removal in continuous treatment system. This discovery provides a promising treatment approach toward actual nitrogen-rich industrial wastewater.
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14
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Cheng C, Zhang J, He Q, Wu H, Chen Y, Xie H, Pavlostathis SG. Exploring simultaneous nitrous oxide and methane sink in wetland sediments under anoxic conditions. WATER RESEARCH 2021; 194:116958. [PMID: 33662685 DOI: 10.1016/j.watres.2021.116958] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 02/02/2021] [Accepted: 02/19/2021] [Indexed: 06/12/2023]
Abstract
Methane (CH4) and nitrous oxide (N2O) are the most powerful greenhouse gases globally; recent emissions exceed previous estimates. The potential link between N2O reduction and CH4 oxidation in anoxic wetland sediments would be a sink for both gases, which has attracted broad attention. To explore the simultaneous N2O and CH4 biotransformation, wetland sediments were used to inoculate an enrichment reactor, continuously fed with CH4 and N2O for 500 days. After enrichment, the CH4 oxidation rate reached 2.8 μmol·g-1dw·d-1, which was 800-fold higher than the rate of the wetland sediments used as inoculum. Moreover, stable isotopic tracing proved CH4 oxidation was driven by N2O consumption under anoxic conditions. Genomic sequencing showed that the microbial community was dominated by methanotrophs. Species of Methylocaldum genus, belonging to γ-Proteobacteria class, were significantly enriched, and became the predominant methanotrophs. Quantitative analysis indicated methane monooxygenase and nitrous oxide reductase increased by 38- and 8-fold compared to the inoculum. As to the potential mechanisms, we propose that N2O-driven CH4 oxidation was mediated by aerobic methanotrophs solely or along with denitrifying bacteria under hypoxia. Electrons and energy are generated and transferred in the oxidative phosphorylation pathway. Our findings expand the range of electron acceptors associated with CH4 oxidation as well as elucidate the significant role of methanotrophs relative to both carbon and nitrogen cycles.
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Affiliation(s)
- Cheng Cheng
- College of Environment and Ecology, Chongqing University, Chongqing 400045, China; School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China; School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia, 30332, USA.
| | - Jian Zhang
- School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China.
| | - Qiang He
- College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Haiming Wu
- School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China
| | - Yi Chen
- College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Huijun Xie
- Environmental Research Institute, Shandong University, Qingdao 266237, China
| | - Spyros G Pavlostathis
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia, 30332, USA
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15
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Dan NH, Rene ER, Le Luu T. Removal of Nutrients From Anaerobically Digested Swine Wastewater Using an Intermittent Cycle Extended Aeration System. Front Microbiol 2020; 11:576438. [PMID: 33178157 PMCID: PMC7596319 DOI: 10.3389/fmicb.2020.576438] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 09/18/2020] [Indexed: 11/13/2022] Open
Abstract
Swine wastewater contains high concentrations of organic compounds, nutrients (nitrogen and phosphorus), heavy metals, and residual antibiotics, amongst others, that have negative impacts on the water environment. The main aim of this work was to remove nutrients from anaerobically digested swine wastewater using an intermittent cycle extended aeration system (ICEAS). The effects of operational parameters such as cycle time, organic loading rate, C/N ratio, and aeration/mixing ratio on the pollutant removal efficiencies of ICEAS were studied and compared with the performance of a conventional sequencing batch reactor (SBR). The following optimal conditions were obtained: cycle time, 6 h; organic loading rate, 0.86 kg COD m-3 day-1; C/N ratio, 2.49-2.82; and aeration/mixing ratio, 1.57. The pH was maintained in the range of 6.0-8.0. The total organic carbon (TOC), total nitrogen (TN), ammonium (NH4 +), total phosphorus (TP), and color removal efficiencies of ICEAS were higher than those of the conventional SBR, with removal efficiencies of 95.22, 88.29, 97.69, 85.81, and 97.84%, respectively, compared to 94.34, 81.16, 94.15, 77.94, and 96.95%, respectively, observed in the SBR. TOC, TN, NH4 +, TP, and the color removal efficiencies of ICEAS were higher by 0.88, 7.13, 3.54, 7.87, and 0.95%, respectively, than the conventional SBR. The good results from this study show that ICEAS is a promising technology for the removal of organic contaminants and nutrients from anaerobically digested swine wastewater and that the effluent water quality meets the Vietnamese discharge standard (QCVN 62-MT:2016/BTNMT) for swine wastewater effluents.
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Affiliation(s)
- Nguyen Hong Dan
- Department of Chemical Engineering, Nong Lam University, Ho Chi Minh City, Vietnam
| | - Eldon R. Rene
- Department of Environmental Engineering and Water Technology, IHE Delft Institute for Water Education, Delft, Netherlands
| | - Tran Le Luu
- Master Program in Water Program Technology, Reuse and Management, Vietnamese German University, Thu Dau Mot, Vietnam
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16
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Kim DD, Park D, Yoon H, Yun T, Song MJ, Yoon S. Quantification of nosZ genes and transcripts in activated sludge microbiomes with novel group-specific qPCR methods validated with metagenomic analyses. WATER RESEARCH 2020; 185:116261. [PMID: 32791454 DOI: 10.1016/j.watres.2020.116261] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 07/14/2020] [Accepted: 08/01/2020] [Indexed: 06/11/2023]
Abstract
Substantial N2O emission results from activated sludge nitrogen removal processes. N2O-reducing organisms possessing NosZ-type N2O reductases have been recognized to play crucial roles in suppressing emission of N2O produced in anoxic activated sludge via denitrification; however, which of the diverse nosZ-possessing organisms function as the major N2O sink in situ remains largely unknown. Here, nosZ genes and transcripts in wastewater microbiomes were analyzed with the group-specific qPCR assays designed de novo combining culture-based and computational approaches. A sewage sample was enriched in a batch reactor fed continuous stream of N2 containing 20-10,000 ppmv N2O with excess amount (10 mM) of acetate as the source of carbon and electrons, where 14 genera of potential N2O-reducers were identified. All available amino acid sequences of NosZ affiliated to these taxa were grouped into five subgroups (two clade I and three clade II groups), and primers/probe sets exclusively and comprehensively targeting the subgroups were designed and validated with in silico PCR. Four distinct activated sludge samples from three different wastewater treatment plants in Korea were analyzed with the qPCR assays and the results were validated with the shotgun metagenome analysis results. With these group-specific qPCR assays, the nosZ genes and transcripts of six additional activated sludge samples were analyzed and the results of the analyses clearly indicated the dominance of two clade II nosZ subgroups (Flavobacterium-like and Dechloromonas-like) among both nosZ gene and transcript pools.
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Affiliation(s)
- Daehyun D Kim
- Department of Civil and Environmental Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 350-701, Korea
| | - Doyoung Park
- Department of Civil and Environmental Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 350-701, Korea
| | - Hyun Yoon
- Department of Civil and Environmental Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 350-701, Korea; Department of Civil and Environmental Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Taeho Yun
- Department of Civil and Environmental Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 350-701, Korea
| | - Min Joon Song
- Department of Civil and Environmental Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 350-701, Korea
| | - Sukhwan Yoon
- Department of Civil and Environmental Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 350-701, Korea.
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17
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Simultaneous Stripping of Ammonia from Leachate: Experimental Insights and Key Microbial Players. WATER 2020. [DOI: 10.3390/w12092494] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Air stripping is commonly used to remove the ammonia in multistage treatment systems for municipal landfill leachate (LFL). This paper proposes a novel approach combining the process of stripping with biological removal of ammonia, based on simultaneous nitrification and denitrification (SND) in a single hybrid sequencing batch reactor (HSBR). To avoid the accumulation of free ammonia (N-FAN), the shallow aeration system was used for the treatment of raw LFL with N-TAN level of 1520 mg/L and pH 9.24. The mean N-FAN removal efficiency of 69% with the reaction rate of 55 mg L−1 h−1 and mean ammonium (N-NH4+) removal efficiency of 84% with the reaction rate of 44 mg L−1 h−1 were achieved within a month in such an HSBR (R1). The comparative HSBR (R2), with conventional aeration system maintaining the same concentration of dissolved oxygen (DO ≤ 1 mg/L), was removing only trace amounts of N-FAN and 48% of N-NH4+. The quantitative analysis of 16S rRNA genes indicated that the number of total bacteria, Actinobacteria, Bacteroidetes, Firmicutes, and Beta- and Gammaproteobacteria increased during the operation of both HSBRs, but was always higher in R1. Moreover, the bacterial community shift was observed since the beginning of the experiment; the relative abundance of Firmicutes, and Beta- and Gammaproteobacteria increased by 5.01, 3.25 and 9.67% respectively, whilst the abundance of Bacteroidetes and Actinobacteria decreased by 15.59 and 0.95%. All of the surveyed bacteria groups, except Gammaproteobacteria, correlated significantly negatively (p < 0.001) with the concentrations of N-NH4+ in the outflows from R1. The results allow us to suppose that simultaneous stripping and SND in a single reactor could be a promising, cost-effective and easy-to-operate solution for LFL treatment.
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18
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Single reactor nitritation-denitritation for high strength digested biosolid thickening lagoon supernatant treatment. Biochem Eng J 2020. [DOI: 10.1016/j.bej.2020.107630] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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19
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Li X, Lu MY, Qiu QC, Huang Y, Li BL, Yuan Y, Yuan Y. The effect of different denitrification and partial nitrification-Anammox coupling forms on nitrogen removal from mature landfill leachate at the pilot-scale. BIORESOURCE TECHNOLOGY 2020; 297:122430. [PMID: 31761626 DOI: 10.1016/j.biortech.2019.122430] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 11/10/2019] [Accepted: 11/12/2019] [Indexed: 06/10/2023]
Abstract
The effects on nitrogen removal from landfill leachate were compared between the denitrification (DN) direct coupling in Partial nitrification (PN)-Anammox (DN+(PN-Anammox)) and pre-DN followed by PN-Anammox (DN-PN-Anammox). Both processes can achieve coupling and high nitrogen removal. However, the DN+(PN-Anammox) process was not conducive to the treatment of high-COD wastewater. The total nitrogen removal rate (TNRR) and total nitrogen removal efficiency (TNRE) were stable at 0.31 kg/(m3·d) and 76.3%. When UASB was added to denitrification and transform the process into DN-PN-Anammox, the influent NH4+-N and COD concentrations were increased to 2230 and 2612 mg/L, TNRR and TNRE reached 0.45 kg/(m3·d) and 96.7%, respectively. The DN-PN-Anammox process not only was able to make full use of degradable COD in wastewater to realize the NO3--N removal, but also benefited the growth of autotrophic bacteria. The DN-PN-Anammox reduced the oxygen supply and was more conducive to the treatment of highly-concentrated mature landfill leachate.
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Affiliation(s)
- Xiang Li
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China; National and Local Joint Engineering Laboratory of Municipal Sewage Resource Utilization Technology, Suzhou 215009, China.
| | - Ming-Yu Lu
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China; National and Local Joint Engineering Laboratory of Municipal Sewage Resource Utilization Technology, Suzhou 215009, China
| | - Qing-Cun Qiu
- Qizi mountain sanitary landfill plant of Suzhou, Suzhou Environmental Sanitation Administration Agency, Suzhou 215009, China
| | - Yong Huang
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China; National and Local Joint Engineering Laboratory of Municipal Sewage Resource Utilization Technology, Suzhou 215009, China
| | - Bo-Lin Li
- School of Resources and Environmental Engineering, Wuhan University of Technology, Wuhan, Hubei, 430070, China
| | - Yi Yuan
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China; National and Local Joint Engineering Laboratory of Municipal Sewage Resource Utilization Technology, Suzhou 215009, China
| | - Yan Yuan
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China; National and Local Joint Engineering Laboratory of Municipal Sewage Resource Utilization Technology, Suzhou 215009, China
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20
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Li M, Mi T, Yu Z, Ma M, Zhen Y. Planktonic Bacterial and Archaeal Communities in an Artificially Irrigated Estuarine Wetland: Diversity, Distribution, and Responses to Environmental Parameters. Microorganisms 2020; 8:microorganisms8020198. [PMID: 32023944 PMCID: PMC7074933 DOI: 10.3390/microorganisms8020198] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2019] [Revised: 01/27/2020] [Accepted: 01/30/2020] [Indexed: 11/21/2022] Open
Abstract
Bacterial and archaeal communities play important roles in wetland ecosystems. Although the microbial communities in the soils and sediments of wetlands have been studied extensively, the comprehensive distributions of planktonic bacterial and archaeal communities and their responses to environmental variables in wetlands remain poorly understood. The present study investigated the spatiotemporal characteristics of the bacterial and archaeal communities in the water of an artificially irrigated estuarine wetland of the Liaohe River, China, explored whether the wetland effluent changed the bacterial and archaeal communities in the Liaohe River, and evaluated the driving environmental factors. Within the study, 16S rRNA quantitative PCR methods and MiSeq high-throughput sequencing were used. The bacterial and archaeal 16S rRNA gene abundances showed significant temporal variation. Meanwhile, the bacterial and archaeal structures showed temporal but not spatial variation in the wetland and did not change in the Liaohe River after wetland drainage. Moreover, the bacterial communities tended to have higher diversity in the wetland water in summer and in the scarce zone, while a relatively higher diversity of archaeal communities was found in autumn and in the intensive zone. DO, pH and PO4-P were proven to be the essential environmental parameters shaping the planktonic bacterial and archaeal community structures in the Liaohe River estuarine wetland (LEW). The LEW had a high potential for methanogenesis, which could be reflected by the composition of the microbial communities.
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Affiliation(s)
- Mingyue Li
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
- Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China
- Key Laboratory of Marine Environment and Ecology, Ministry of Education, Ocean University of China, Qingdao 266100, China
| | - Tiezhu Mi
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
- Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China
- Key Laboratory of Marine Environment and Ecology, Ministry of Education, Ocean University of China, Qingdao 266100, China
| | - Zhigang Yu
- Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China
- Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education/Institute for Advanced Ocean Study, Ocean University of China, Qingdao 266100, China
| | - Manman Ma
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
- Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China
- Key Laboratory of Marine Environment and Ecology, Ministry of Education, Ocean University of China, Qingdao 266100, China
| | - Yu Zhen
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
- Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China
- Key Laboratory of Marine Environment and Ecology, Ministry of Education, Ocean University of China, Qingdao 266100, China
- Correspondence: ; Tel.: +86-532-6678-1940
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22
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How SW, Chua ASM, Ngoh GC, Nittami T, Curtis TP. Enhanced nitrogen removal in an anoxic-oxic-anoxic process treating low COD/N tropical wastewater: Low-dissolved oxygen nitrification and utilization of slowly-biodegradable COD for denitrification. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 693:133526. [PMID: 31376760 DOI: 10.1016/j.scitotenv.2019.07.332] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 07/17/2019] [Accepted: 07/20/2019] [Indexed: 06/10/2023]
Abstract
Many wastewater treatment plants (WWTPs) operating in biological nitrogen removal activated sludge process in the tropics are facing the pressure of increasingly stringent effluent standards while seeking solutions to reduce the plants' energy consumption and operating cost. This study investigated the feasibility of applying low-dissolved oxygen (low-DO) nitrification and utilizing slowly-biodegradable chemical oxygen demand (sbCOD) for denitrification, which helps to reduce energy usage and operating cost in treating low soluble COD-to-nitrogen tropical wastewater. The tropical wastewater was first characterized using wastewater fractionation and respirometry batch tests. Then, a lab-scale sequencing batch reactor (SBR) was operated to evaluate the long-term stability of low-DO nitrification and utilizing sbCOD for denitrification in an anoxic-oxic (AO) process treating tropical wastewater. The wastewater fractionation experiment revealed that particulate settleable solids (PSS) in the wastewater provided slowly-biodegradable COD (sbCOD), which made up the major part (51 ± 10%) of the total COD. The PSS hydrolysis rate constant at tropical temperature (30 °C) was 2.5 times higher than that at 20 °C, suggesting that sbCOD may be utilized for denitrification. During the SBR operation, high nitrification efficiency (93 ± 6%) was attained at low-DO condition (0.9 ± 0.1 mg O2/L). Utilizing sbCOD for post-anoxic denitrification in the SBR reduced the effluent nitrate concentration. Quantitative polymerase chain reaction, 16S rRNA amplicon sequencing and fluorescence in-situ hybridization revealed that the genus Nitrospira was a dominant nitrifier. 16S rRNA amplicon sequencing result suggested that 50% of the Nitrospira-related operational taxonomic units were affiliated with comammox, which may imply that the low-DO condition and the warm wastewater promoted their growth. The nitrogen removal in a tropical AO process was enhanced by incorporating low-DO nitrification and utilizing sbCOD for post-anoxic denitrification, which contributes to an improved energy sustainability of WWTPs.
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Affiliation(s)
- Seow Wah How
- Department of Chemical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Adeline Seak May Chua
- Department of Chemical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia.
| | - Gek Cheng Ngoh
- Department of Chemical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Tadashi Nittami
- Division of Materials Science and Chemical Engineering, Faculty of Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan
| | - Thomas P Curtis
- School of Engineering, Newcastle University, Newcastle upon Tyne NE1 7RU, United Kingdom
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Zhao X, Yang J, Tu C, Zhou Z, Wu W, Chen G, Yao J, Ruan D, Qiu Z. A full-scale survey of sludge landfill: sludge properties, leachate characteristics and microbial community structure. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2019; 80:1185-1195. [PMID: 31799962 DOI: 10.2166/wst.2019.362] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
In this study, a full-scale survey was conducted of a sludge landfill that had been sealed for 10 years to investigate sludge properties, leachate characteristics and microbial community structure. Vertical distribution of sludge and leachate pollutants in the landfill site showed that the sludge and soluble pollutants in the leachate were both distributed almost evenly even after long-term anaerobic digestion, and higher concentrations of soluble pollutants and richness of microbial community were observed at the middle layer. Compared to dewatered excess sludge generated from the activated sludge process before landfill, landfill sludge had a much lower organic content (28.1%), smaller particle size and worse dewaterability. Compared to municipal waste landfill, sludge landfill generated leachate with a lower concentration of organic substances, and comparable concentrations of nitrogenous and phosphorus pollutants. Bacterial community analysis by Illumina MiSeq sequencing showed that Proteobacteria, Firmicutes, Chloroflexi, Actinobacteria and Bacteroidetes were the major phyla, and some new genera (Methylocystaceae, Mariniphaga and Aminicenantes) were enriched in the sludge landfill. Archaeal community analysis showed that aceticlastic methanogenesis by Methanosaeta and Methanosarcina was the main pathway for methane production in the sludge landfill, in contrast to waste landfill with hydrogenotrophic methanogenesis as the main pathway.
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Affiliation(s)
- Xiaodan Zhao
- Shanghai Engineering Research Center of Energy - Saving in Heat Exchange Systems, College of Environmental and Chemical Engineering, Shanghai University of Electric Power, Shanghai 200090, China E-mail:
| | - Jiazhe Yang
- Shanghai Engineering Research Center of Energy - Saving in Heat Exchange Systems, College of Environmental and Chemical Engineering, Shanghai University of Electric Power, Shanghai 200090, China E-mail:
| | - Chengqin Tu
- Shanghai Engineering Research Center of Energy - Saving in Heat Exchange Systems, College of Environmental and Chemical Engineering, Shanghai University of Electric Power, Shanghai 200090, China E-mail:
| | - Zhen Zhou
- Shanghai Engineering Research Center of Energy - Saving in Heat Exchange Systems, College of Environmental and Chemical Engineering, Shanghai University of Electric Power, Shanghai 200090, China E-mail:
| | - Wei Wu
- Shanghai Engineering Research Center of Energy - Saving in Heat Exchange Systems, College of Environmental and Chemical Engineering, Shanghai University of Electric Power, Shanghai 200090, China E-mail:
| | - Guang Chen
- Shanghai Chengtou Wastewater Treatment Co., Ltd, Shanghai 201203, China
| | - Jie Yao
- Shanghai Chengtou Wastewater Treatment Co., Ltd, Shanghai 201203, China
| | - Danian Ruan
- Shanghai Engineering Research Center of Energy - Saving in Heat Exchange Systems, College of Environmental and Chemical Engineering, Shanghai University of Electric Power, Shanghai 200090, China E-mail:
| | - Zhan Qiu
- Shanghai Chengtou Wastewater Treatment Co., Ltd, Shanghai 201203, China
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Ding X, Wei D, Guo W, Wang B, Meng Z, Feng R, Du B, Wei Q. Biological denitrification in an anoxic sequencing batch biofilm reactor: Performance evaluation, nitrous oxide emission and microbial community. BIORESOURCE TECHNOLOGY 2019; 285:121359. [PMID: 31015181 DOI: 10.1016/j.biortech.2019.121359] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 04/14/2019] [Accepted: 04/16/2019] [Indexed: 06/09/2023]
Abstract
The present study evaluated the performance of biological denitrification in an anoxic sequencing batch biofilm reactor (ASBBR) and its nitrous oxide (N2O) emission. After 90 days operation, the effluent chemical oxygen demand and total nitrogen removal efficiencies high of 94.8% and 95.0%, respectively. Both polysaccharides and protein contents were reduced in bound EPS (TB-EPS) and loosely bound EPS (LB-EPS) after biofilm formation. According to typical cycle, N2O release rate was related to the free nitrous acid (FNA) concentration with the maximum value of 3.88 μg/min and total conversion rate of 1.27%. Two components were identified from EEM-PARAFAC model in soluble microbial products (SMP). Protein-like substances for component 1 changed significantly in denitrification process, whereas humic-like and fulvic acid-like substances for component 2 remained relatively stable. High-throughput sequencing results showed that Lysobacter, Tolumonas and Thauera were the dominant genera, indicating the co-existence of autotrophic and heterotrophic denitrifiers in ASBBR.
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Affiliation(s)
- Xiangwei Ding
- School of Water Conservancy and Environment, University of Jinan, Jinan 250022, PR China
| | - Dong Wei
- School of Water Conservancy and Environment, University of Jinan, Jinan 250022, PR China.
| | - Wenshan Guo
- School of Civil and Environmental Engineering, University of Technology Sydney, Broadway, NSW 2007, Australia
| | - Ben Wang
- School of Water Conservancy and Environment, University of Jinan, Jinan 250022, PR China
| | - Zijun Meng
- School of Water Conservancy and Environment, University of Jinan, Jinan 250022, PR China
| | - Rui Feng
- School of Water Conservancy and Environment, University of Jinan, Jinan 250022, PR China
| | - Bin Du
- School of Water Conservancy and Environment, University of Jinan, Jinan 250022, PR China
| | - Qin Wei
- Key Laboratory of Interfacial Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, PR China
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Wang H, Sun Y, Wu G, Guan Y. Effect of anoxic to aerobic duration ratios on nitrogen removal and nitrous oxide emission in the multiple anoxic/aerobic process. ENVIRONMENTAL TECHNOLOGY 2019; 40:1676-1685. [PMID: 29333979 DOI: 10.1080/09593330.2018.1427801] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 01/09/2018] [Indexed: 06/07/2023]
Abstract
Characteristics of nitrogen removal and nitrous oxide (N2O) emission in the multiple anoxic/aerobic (AO) process were examined in three sequencing batch reactors (SBRs) with different anoxic durations (50 min, SBRH; 40 min, SBRM; 30 min, SBRL) and a fixed aerobic duration of 30 min. The highest total inorganic nitrogen removal percentage of 85.8% was obtained in SBRH, while a minimum N2O emission factor of 1.9% was obtained in SBRL. During nitrification batch experiments, the N2O emission factor and emission rate were both lower in SBRH than SBRL. More N2O production was obtained during denitrification in SBRH when denitrifiers utilized intracellular organic carbon. Nitrite reduction by heterotrophs was the main N2O production pathway during simultaneous nitrification and denitrification in SBRH and SBRL, with the N2O emission factor of 31.3% and 36.3%, respectively. Adequate anoxic duration and lowering aerobic nitrite concentrations could be adopted to mitigate N2O emission in the multiple AO process. The dominant microorganisms at the phylum level in all reactors were Proteobacteria and Bacteroidetes, while the abundance of Nitrospira was the highest in SBRH with relatively lowest dissolved oxygen concentrations.
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Affiliation(s)
- Huoqing Wang
- a Guangdong Province Engineering Research Center for Urban Water Recycling and Environmental Safety, Graduate School at Shenzhen , Tsinghua University , Shenzhen , People's Republic of China
| | - Yuepeng Sun
- a Guangdong Province Engineering Research Center for Urban Water Recycling and Environmental Safety, Graduate School at Shenzhen , Tsinghua University , Shenzhen , People's Republic of China
| | - Guangxue Wu
- a Guangdong Province Engineering Research Center for Urban Water Recycling and Environmental Safety, Graduate School at Shenzhen , Tsinghua University , Shenzhen , People's Republic of China
| | - Yuntao Guan
- a Guangdong Province Engineering Research Center for Urban Water Recycling and Environmental Safety, Graduate School at Shenzhen , Tsinghua University , Shenzhen , People's Republic of China
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Zhang C, Du Z, Li B, Sun X, Wang J, Wang J, Zhu L. Evaluating toxicity of 1-octyl-3-methylimidazolium hexafluorophosphate to microorganisms in soil. CHEMOSPHERE 2018; 210:762-768. [PMID: 30036824 DOI: 10.1016/j.chemosphere.2018.07.105] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2018] [Revised: 07/16/2018] [Accepted: 07/18/2018] [Indexed: 06/08/2023]
Abstract
Ionic liquids (ILs) were widely applied because of their excellent properties. The present investigation studied the toxicity of the IL 1-octyl-3-methylimidazolium hexafluorophosphate ([Omim]PF6) to the soil microbial population and community diversity with dose (1.0, 2.0, 4.0, 6.0, and 8.0 mg kg-1) and exposure time (7, 10, and 13 d). The results show the IL was stable during the entire experimental period. The Biolog-ECO plate results indicated that the average well color development (AWCD) in the 6.0 and 8.0 mg kg-1 treatments was lower than these in the other treatments. The diversity indices of the Biolog analysis were significantly reduced. The abundance of the ammonia-oxidizing archaea (AOA-) and the ammonia-oxidizing bacteria (AOB-) ammonia monooxygenase (amoA) genes was measured by the real-time polymerase chain reaction (RT-PCR). In the treatments of 4.0, 6.0 and 8.0 mg kg-1, the abundance of amoA genes of the AOA- and AOB- were inhibited by IL [Omim]PF6.
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Affiliation(s)
- Cheng Zhang
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Taian, 271018, China.
| | - Zhongkun Du
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Taian, 271018, China.
| | - Bing Li
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Taian, 271018, China.
| | - Xi Sun
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Taian, 271018, China.
| | - Jun Wang
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Taian, 271018, China.
| | - Jinhua Wang
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Taian, 271018, China.
| | - Lusheng Zhu
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Taian, 271018, China.
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Gabarró J, Guivernau M, Burgos L, Garanto O, Bonmatí A. Startup strategy for nitrogen removal via nitrite in a BAF system. Bioprocess Biosyst Eng 2018; 42:233-243. [PMID: 30367248 DOI: 10.1007/s00449-018-2028-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Accepted: 10/17/2018] [Indexed: 10/28/2022]
Abstract
A biological aerated filter (BAF) pilot plant consisting of two reactors (aerobic and anoxic one) was used to determine a strategy to remove nitrogen via nitrite. RNA/DNA analysis was performed to assess microbial activity and support chemical results. In less than 13 days the pilot plant was able to remove COD and suspended solids. Nitrogen removal via nitrite pathway could not be observed until day 130 when the empty bed contact time (EBCT) was set at 0.71 h. Nitrite was detected in the aerated BAF effluent but never nitrate. qPCR of amoA gene from RNA and DNA extracts of the aerobic biofilm confirmed that ammonia oxidizing bacteria (AOB) were present from the beginning of the operation but not active. AOB activity increased with time, reaching stability from operational day 124. The combination of both, low EBCT together with high OLR, has been demonstrated to be a feasible strategy to startup a BAF to achieve nitrogen removal via nitrite.
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Affiliation(s)
- Jordi Gabarró
- GIRO, Institute of Agrifood Research and Technology (IRTA), Torre Marimon, Caldes de Montbui, E08140, Barcelona, Catalonia, Spain.,TELWE S.A., Camprodon 49, 17240, Llagostera, Catalonia, Spain
| | - Miriam Guivernau
- GIRO, Institute of Agrifood Research and Technology (IRTA), Torre Marimon, Caldes de Montbui, E08140, Barcelona, Catalonia, Spain
| | - Laura Burgos
- GIRO, Institute of Agrifood Research and Technology (IRTA), Torre Marimon, Caldes de Montbui, E08140, Barcelona, Catalonia, Spain
| | - Oswald Garanto
- PESA Medio Ambiente, Avinguda de la Generalitat, 216, 08174, Sant Cugat del Vallès, Catalonia, Spain
| | - August Bonmatí
- GIRO, Institute of Agrifood Research and Technology (IRTA), Torre Marimon, Caldes de Montbui, E08140, Barcelona, Catalonia, Spain.
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28
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Xu H, Li Y, Ding M, Chen W, Wang K, Lu C. Simultaneous removal of dissolved organic matter and nitrate from sewage treatment plant effluents using photocatalytic membranes. WATER RESEARCH 2018; 143:250-259. [PMID: 29960179 DOI: 10.1016/j.watres.2018.06.044] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2018] [Revised: 05/24/2018] [Accepted: 06/18/2018] [Indexed: 06/08/2023]
Abstract
The residual dissolved organic matter (DOM) and nitrate in sewage treatment plant (STP) effluent have potential negative impacts on the aqueous environment. To that end, we used formic acid (FA) to enhance the photochemical behavior of the photocatalytic membrane for the simultaneous removal of DOM and nitrate from secondary STP effluent. Effluent samples were collected from two different biological treatment processes, Anaerobic-Oxic and Anaerobic-Anoxic-Oxic-membrane bioreactor, respectively. Through Fourier transform-ion cyclotron resonance-mass spectrometry (FT-ICR-MS) analysis, we found that the addition of FA resulted in a similar molecular transformation in different STP effluent samples. Besides, the radical signal of the carboxyl anion could be observed during the photocatalytic process. Based on the results, we proposed the mechanism of the process that carboxyl anion radicals generated by FA could attack DOM and result in further oxidation of the DOM transition state to CO2 or small molecule by nitrate. Meanwhile, CHON and CHOS compounds in DOM were attacked by the carboxyl anion radicals more easily than CHO compounds. Moreover, long-term use of the membrane confirmed its durability and reusability in practical applications. At a moderate FA concentration and lower hydraulic retention time, the nitrate and DOM removal efficiencies for the sample from JX STP were 68% and 70%, respectively, whereas those of the CD STP sample were 85% and 60%. The removal of DOM and nitrate from different STP effluents using photocatalytic membranes is an advanced approach for the treatment of secondary effluent, and may be applicable to other membranes or systems.
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Affiliation(s)
- Hang Xu
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China; Hohai University, College of Environmental Science, Nanjing 210098, China
| | - Yang Li
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China; Hohai University, College of Environmental Science, Nanjing 210098, China.
| | - Mingmei Ding
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China; Hohai University, College of Environmental Science, Nanjing 210098, China
| | - Wei Chen
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China; Hohai University, College of Environmental Science, Nanjing 210098, China
| | - Kang Wang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China; Hohai University, College of Environmental Science, Nanjing 210098, China
| | - Chunhui Lu
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing, China
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Widespread Antibiotic, Biocide, and Metal Resistance in Microbial Communities Inhabiting a Municipal Waste Environment and Anthropogenically Impacted River. mSphere 2018; 3:3/5/e00346-18. [PMID: 30258036 PMCID: PMC6158514 DOI: 10.1128/msphere.00346-18] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Landfill leachate is a persistent contamination threat for terrestrial waters. Microbial metabolism in landfills transforms contaminants and contributes to greenhouse gas emissions. A better understanding of landfill-associated microbial communities will inform bioremediation of solid waste environments and improve pathogen monitoring. We leveraged shotgun metagenomics to investigate the microbial communities of the Riverton City dump and the adjoining Duhaney River near Kingston City, Jamaica. We identified no overlap between the microbial communities inhabiting the Riverton City dump leachate and the Duhaney River. Both communities are predicted to degrade aromatic compounds, which are ubiquitous environmental pollutants. Adversely, microbes in both environments are predicted to withstand widely used antibiotics, antiseptics, and metal contamination. The absence of evidence for microbial transfer from the leachate to the river is encouraging; however, the Duhaney River contained several organisms with predicted pathogenic lifestyles, indicating that the river represents a human health risk regardless of impact from the dump. The Riverton City dump is Jamaica’s largest solid waste disposal site, but it lacks engineered protection for leachate containment and treatment. Shotgun metagenomics was used to survey the microbial communities in the Riverton City dump leachate and in surface waters of the Duhaney River, an urban waterway abutting the dump. The community within the leachate pond was taxonomically distinct from that found in the surface waters of the Duhaney River. Higher microbial diversity was observed within the dump leachate, with members of the Bacteroidetes, Firmicutes, Gammaproteobacteria, Deltaproteobacteria, and Tenericutes being the most abundant, while the river community was dominated by Alphaproteobacteria, Betaproteobacteria, and Gammaproteobacteria. The microbial communities exhibit similar functional potential profiles, including chemoorganoheterotrophy as the dominant metabolism, and the potential to degrade aromatic compounds. From reconstruction of metagenome-assembled genomes (MAGs), organisms within both environments are predicted to survive in the presence of multiple antibiotics, antiseptics, biocides, and metals. Strong virulence potential coincided with the most diverse multiple resistance profiles in 1 of 5 leachate MAGs and 5 of 33 river MAGs. Unexpectedly, the microbial resistance profiles were more varied and widespread in the river populations, where we had expected the chemical composition of the leachate to select and enrich for resistance characteristics. This study provides valuable insights into the total functional potential of a landfill leachate microbial community and identifies possible human health hazards within the Duhaney River and Riverton City dump, urban environments with the potential to impact human populations. IMPORTANCE Landfill leachate is a persistent contamination threat for terrestrial waters. Microbial metabolism in landfills transforms contaminants and contributes to greenhouse gas emissions. A better understanding of landfill-associated microbial communities will inform bioremediation of solid waste environments and improve pathogen monitoring. We leveraged shotgun metagenomics to investigate the microbial communities of the Riverton City dump and the adjoining Duhaney River near Kingston City, Jamaica. We identified no overlap between the microbial communities inhabiting the Riverton City dump leachate and the Duhaney River. Both communities are predicted to degrade aromatic compounds, which are ubiquitous environmental pollutants. Adversely, microbes in both environments are predicted to withstand widely used antibiotics, antiseptics, and metal contamination. The absence of evidence for microbial transfer from the leachate to the river is encouraging; however, the Duhaney River contained several organisms with predicted pathogenic lifestyles, indicating that the river represents a human health risk regardless of impact from the dump.
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Bian R, Xin D, Chai X. A Simulation model for estimating methane oxidation and emission from landfill cover soils. WASTE MANAGEMENT (NEW YORK, N.Y.) 2018; 77:426-434. [PMID: 29709311 DOI: 10.1016/j.wasman.2018.04.029] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 04/14/2018] [Accepted: 04/18/2018] [Indexed: 06/08/2023]
Abstract
Quantification of methane (CH4) oxidation and emission from landfill cover soils is important for evaluating measures to mitigate anthropogenic greenhouse gas emissions. In this study, a model that combines the multicomponent diffusive equation and Darcy's law, coupled with the dual Monod kinetic equation, was established to simulate CH4 transport, oxidation and emission in landfill cover soils. Sensitivity analysis was performed to illustrate the influence of model parameters on CH4 transport, oxidation and emission. The model was then applied to predict CH4 emissions from several column experiments. The results of the sensitivity analysis showed that a high CH4 oxidation rate can be obtained with a high Vmax of cover soil, even for a low cover soil thickness, and that oxidation efficiency is constant when the thickness of the cover soil becomes greater than a threshold value. The simulated results fitted well with the measured values, confirming that the new model provides a reliable method for estimating CH4 emissions from landfills.
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Affiliation(s)
- Rongxing Bian
- State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, China
| | - Danhui Xin
- State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, China; Department of Civil and Environmental Engineering, University of Delaware, Newark, DE 19716, United States
| | - Xiaoli Chai
- State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, China.
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Sun Y, Wang H, Wu G, Guan Y. Nitrogen removal and nitrous oxide emission from a step-feeding multiple anoxic and aerobic process. ENVIRONMENTAL TECHNOLOGY 2018; 39:814-823. [PMID: 28345390 DOI: 10.1080/09593330.2017.1311947] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2016] [Accepted: 03/22/2017] [Indexed: 06/06/2023]
Abstract
The multiple anoxic and aerobic (AO) process is an advanced biological nitrogen-removal process, and nitrous oxide (N2O) emission might affect its sustainable application. Nitrogen removal and N2O emission in a step-feeding multiple AO sequencing batch reactor (SBRS) was examined, in comparison with a one-feeding sequencing batch reactor (SBRO). Nitrogen removal was enhanced by 12.6% in SBRS compared to the removal percentage of 75.8% in SBRO. Activated sludge in SBRs possessed a higher N2O emission factor during nitrification, denitrification and simultaneous nitrification and denitrification (SND) than in SBRO. A high N2O emission factor was observed during SND in both reactors, with the emission factor of 4.38% in SBRS and 4.66% in SBRO. More N2O emission occurred in the presence of nitrite. Bacteroidetes and Proteobacteria dominated in both SBRS and SBRO. A similar abundance of Thauera, Dechloromonas and Zoogloea possible for denitrification was observed in SBRS and SBRO. Moreover, nosZ from Proteobacteria dominated in both SBRS and SBRO, with dominating genus of Acidovorax, Ralstonia, Thauera and Marinobacter.
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Affiliation(s)
- Yuepeng Sun
- a Key Laboratory of Microorganism Application and Risk Control (MARC) of Shenzhen, Graduate School at Shenzhen , Tsinghua University , Shenzhen , People's Republic of China
| | - Huoqing Wang
- a Key Laboratory of Microorganism Application and Risk Control (MARC) of Shenzhen, Graduate School at Shenzhen , Tsinghua University , Shenzhen , People's Republic of China
| | - Guangxue Wu
- a Key Laboratory of Microorganism Application and Risk Control (MARC) of Shenzhen, Graduate School at Shenzhen , Tsinghua University , Shenzhen , People's Republic of China
| | - Yuntao Guan
- a Key Laboratory of Microorganism Application and Risk Control (MARC) of Shenzhen, Graduate School at Shenzhen , Tsinghua University , Shenzhen , People's Republic of China
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32
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Bian R, Xin D, Chai X. A simulation model for methane emissions from landfills with interaction of vegetation and cover soil. WASTE MANAGEMENT (NEW YORK, N.Y.) 2018; 71:267-276. [PMID: 29050973 DOI: 10.1016/j.wasman.2017.10.013] [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: 06/12/2017] [Revised: 09/10/2017] [Accepted: 10/12/2017] [Indexed: 06/07/2023]
Abstract
Global climate change and ecological problems brought about by greenhouse gas effect have become a severe threat to humanity in the 21st century. Vegetation plays an important role in methane (CH4) transport, oxidation and emissions from municipal solid waste (MSW) landfills as it modifies the physical and chemical properties of the cover soil, and transports CH4 to the atmosphere directly via their conduits, which are mainly aerenchymatous structures. In this study, a novel 2-D simulation CH4 emission model was established, based on an interactive mechanism of cover soil and vegetation, to model CH4 transport, oxidation and emissions in landfill cover soil. Results of the simulation model showed that the distribution of CH4 concentration and emission fluxes displayed a significant difference between vegetated and non-vegetated areas. CH4 emission flux was 1-2 orders of magnitude higher than bare areas in simulation conditions. Vegetation play a negative role in CH4 emissions from landfill cover soil due to the strong CH4 transport capacity even though vegetation also promotes CH4 oxidation via changing properties of cover soil and emitting O2 via root system. The model will be proposed to allow decision makers to reconsider the actual CH4 emission from vegetated and non-vegetated covered landfills.
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Affiliation(s)
- Rongxing Bian
- State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, China
| | - Danhui Xin
- Department of Civil and Environmental Engineering, University of Delaware, Newark, DE 19716, United States
| | - Xiaoli Chai
- State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, China.
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33
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Kinh CT, Suenaga T, Hori T, Riya S, Hosomi M, Smets BF, Terada A. Counter-diffusion biofilms have lower N 2O emissions than co-diffusion biofilms during simultaneous nitrification and denitrification: Insights from depth-profile analysis. WATER RESEARCH 2017; 124:363-371. [PMID: 28780360 DOI: 10.1016/j.watres.2017.07.058] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Revised: 07/18/2017] [Accepted: 07/23/2017] [Indexed: 06/07/2023]
Abstract
The goal of this study was to investigate the effectiveness of a membrane-aerated biofilm reactor (MABR), a representative of counter-current substrate diffusion geometry, in mitigating nitrous oxide (N2O) emission. Two laboratory-scale reactors with the same dimensions but distinct biofilm geometries, i.e., a MABR and a conventional biofilm reactor (CBR) employing co-current substrate diffusion geometry, were operated to determine depth profiles of dissolved oxygen (DO), nitrous oxide (N2O), functional gene abundance and microbial community structure. Surficial nitrogen removal rate was slightly higher in the MABR (11.0 ± 0.80 g-N/(m2 day) than in the CBR (9.71 ± 0.94 g-N/(m2 day), while total organic carbon removal efficiencies were comparable (96.9 ± 1.0% for MABR and 98.0 ± 0.8% for CBR). In stark contrast, the dissolved N2O concentration in the MABR was two orders of magnitude lower (0.011 ± 0.001 mg N2O-N/L) than that in the CBR (1.38 ± 0.25 mg N2O-N/L), resulting in distinct N2O emission factors (0.0058 ± 0.0005% in the MABR vs. 0.72 ± 0.13% in the CBR). Analysis on local net N2O production and consumption rates unveiled that zones for N2O production and consumption were adjacent in the MABR biofilm. Real-time quantitative PCR indicated higher abundance of denitrifying genes, especially nitrous oxide reductase (nosZ) genes, in the MABR versus the CBR. Analyses of the microbial community composition via 16S rRNA gene amplicon sequencing revealed the abundant presence of the genera Thauera (31.2 ± 11%), Rhizobium (10.9 ± 6.6%), Stenotrophomonas (6.8 ± 2.7%), Sphingobacteria (3.2 ± 1.1%) and Brevundimonas (2.5 ± 1.0%) as potential N2O-reducing bacteria in the MABR.
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Affiliation(s)
- Co Thi Kinh
- Department of Chemical Engineering, Tokyo University of Agriculture and Technology, Naka 2-24-16, Koganei, Tokyo, 184-8588, Japan
| | - Toshikazu Suenaga
- Department of Chemical Engineering, Tokyo University of Agriculture and Technology, Naka 2-24-16, Koganei, Tokyo, 184-8588, Japan
| | - Tomoyuki Hori
- Institute for Environmental Management Technology, National Institute of Advanced Industrial Science and Technology (AIST), Onogawa 16-1, Tsukuba, Ibaraki, 305-8569, Japan
| | - Shohei Riya
- Department of Chemical Engineering, Tokyo University of Agriculture and Technology, Naka 2-24-16, Koganei, Tokyo, 184-8588, Japan
| | - Masaaki Hosomi
- Department of Chemical Engineering, Tokyo University of Agriculture and Technology, Naka 2-24-16, Koganei, Tokyo, 184-8588, Japan
| | - Barth F Smets
- Department of Environmental Engineering, Technical University of Denmark, Miljoevej, 2800, Lyngby, Denmark
| | - Akihiko Terada
- Department of Chemical Engineering, Tokyo University of Agriculture and Technology, Naka 2-24-16, Koganei, Tokyo, 184-8588, Japan.
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Jurczyk Ł, Koc-Jurczyk J. Quantitative dynamics of ammonia-oxidizers during biological stabilization of municipal landfill leachate pretreated by Fenton's reagent at neutral pH. WASTE MANAGEMENT (NEW YORK, N.Y.) 2017; 63:310-326. [PMID: 28159310 DOI: 10.1016/j.wasman.2017.01.028] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Revised: 01/04/2017] [Accepted: 01/17/2017] [Indexed: 06/06/2023]
Abstract
The application of multi-stage systems including biological step, for the treatment of leachate from municipal landfills, is economically and technologically justified. When microbial activity is utilized as 2nd stage of treatment, the task of 1st stage is to increase the bioavailability of organic matter. In this work, the effect of advanced oxidation process by Fenton's reagent for treatment efficiency of landfill leachate in the sequencing batch reactor was assessed. The quantitative dynamics of bacteria taking a part in ammonia removal process was evaluated by determination of number of DNA copies of 16S rRNA and amoA. Products of neutral pH chemical oxidation, had a definite positive impact on the quantity of β-proteobacteria 16S rRNA, whereas the same gene specified for Nitrospira sp. as well as amoA did not show a significant increase during the process of biological treatment, regardless of whether the reactor was fed with raw leachate or chemically pre-treated.
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Affiliation(s)
- Łukasz Jurczyk
- University of Rzeszow, Department of Biology and Agriculture, Cwiklinskiej 1b Str., 35-601 Rzeszow, Poland.
| | - Justyna Koc-Jurczyk
- University of Rzeszow, Department of Biology and Agriculture, Cwiklinskiej 1b Str., 35-601 Rzeszow, Poland
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Remmas N, Roukouni C, Ntougias S. Bacterial community structure and prevalence of Pusillimonas-like bacteria in aged landfill leachate. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:6757-6769. [PMID: 28091993 DOI: 10.1007/s11356-017-8416-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Accepted: 01/05/2017] [Indexed: 06/06/2023]
Abstract
Although several works have been performed from an engineering point of view, a limited number of studies have focused on microbial communities involved in the humification of aged landfill leachates. In this work, cultivation techniques, next-generation sequencing, and phospholipid fatty acid analysis were adopted to decrypt the diversity and the ecophysiological properties of the dominant microbiota in aged landfill leachate. Based on Illumina sequencing, Betaproteobacteria, Bacteroidetes, Actinobacteria, and Alphaproteobacteria dominated the aged landfill leachate. The main taxa identified at genus level were Pusillimonas-like bacteria and Leucobacter (41.46% of total reads), with all of them being also isolated through cultivation. The presence of Pusillimonas-like bacteria was also verified by the detection of cyclo17:0 and iso-19:0 fatty acids in aged landfill leachate microbiota. Despite that almost all bacterial isolates exhibited extracellular lipolytic ability, no particular specificity was observed in the type of substrate utilized. The prevalence of effective degraders, such as Pusillimonas-like bacteria, makes the aged landfill leachate an ideal source for isolation of novel microorganisms with potential in situ bioremediation uses.
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Affiliation(s)
- Nikolaos Remmas
- Laboratory of Wastewater Management and Treatment Technologies, Department of Environmental Engineering, Democritus University of Thrace, Vas. Sofias 12, 67100, Xanthi, Greece
| | - Charikleia Roukouni
- Laboratory of Wastewater Management and Treatment Technologies, Department of Environmental Engineering, Democritus University of Thrace, Vas. Sofias 12, 67100, Xanthi, Greece
| | - Spyridon Ntougias
- Laboratory of Wastewater Management and Treatment Technologies, Department of Environmental Engineering, Democritus University of Thrace, Vas. Sofias 12, 67100, Xanthi, Greece.
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How the performance of a biological pre-oxidation step can affect a downstream photo-Fenton process on the remediation of mature landfill leachates: Assessment of kinetic parameters and characterization of the bacterial communities. Sep Purif Technol 2017. [DOI: 10.1016/j.seppur.2016.11.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Change in microbial community in landfill refuse contaminated with antibiotics facilitates denitrification more than the increase in ARG over long-term. Sci Rep 2017; 7:41230. [PMID: 28120869 PMCID: PMC5264584 DOI: 10.1038/srep41230] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Accepted: 12/16/2016] [Indexed: 11/09/2022] Open
Abstract
In this study, the addition of sulfamethazine (SMT) to landfill refuse decreased nitrogen intermediates (e.g. N2O and NO) and dinitrogen (N2) gas fluxes to <0.5 μg-N/kg-refuse·h-1, while the N2O and N2 flux were at ~1.5 and 5.0 μg-N/kg-refuse·h-1 respectively in samples to which oxytetracycline (OTC) had been added. The ARG (antibiotic resistance gene) levels in the refuse increased tenfold after long-term exposure to antibiotics, followed by a fourfold increase in the N2 flux, but SMT-amended samples with the largest resistome facilitated the denitrification (the nitrogen accumulated as NO gas at ~6 μg-N/kg-refuse·h-1) to a lesser extent than OTC-amended samples. Further, deep sequencing results show that long-term OTC exposure partially substituted Hyphomicrobium, Fulvivirga, and Caldilinea (>5%) for the dominant bacterial hosts (Rhodothermus, ~20%) harboring nosZ and norB genes that significantly correlated with nitrogen emission pattern, while sulfamethazine amendment completely reduced the relative abundance of the "original inhabitants" functioning to produce NOx gas reduction. The main ARG carriers (Pseudomonas) that were substantially enriched in the SMT group had lower levels of denitrifying functional genes, which could imply that denitrification is influenced more by bacterial dynamics than by abundance of ARGs under antibiotic pressures.
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Cao Q, Wang H, Chen X, Wang R, Liu J. Composition and distribution of microbial communities in natural river wetlands and corresponding constructed wetlands. ECOLOGICAL ENGINEERING 2017; 98:40-48. [DOI: 10.1016/j.ecoleng.2016.10.063] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2024]
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39
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Liu T, Mao YJ, Shi YP, Quan X. Start-up and bacterial community compositions of partial nitrification in moving bed biofilm reactor. Appl Microbiol Biotechnol 2016; 101:2563-2574. [DOI: 10.1007/s00253-016-8003-9] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Revised: 11/07/2016] [Accepted: 11/09/2016] [Indexed: 10/20/2022]
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40
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Remmas N, Melidis P, Katsioupi E, Ntougias S. Effects of high organic load on amoA and nirS gene diversity of an intermittently aerated and fed membrane bioreactor treating landfill leachate. BIORESOURCE TECHNOLOGY 2016; 220:557-565. [PMID: 27614578 DOI: 10.1016/j.biortech.2016.09.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 08/28/2016] [Accepted: 09/02/2016] [Indexed: 06/06/2023]
Abstract
The effects of external carbon source addition on the nitrification and denitrification process were investigated in an intermittently aerated and fed membrane bioreactor treating landfill leachate by recording system performance, and amoA and nirS diversity dynamics using pyrosequencing. By adding 950mg/L glycerol, denitrification was optimized, resulting in total nitrogen removal efficiency of 81.0±2.4%. Under these conditions, amoA diversity was dominated by genotypes related to Nitrosomonas europaea, while increase in leachate's content and in glycerol addition by 50% led to irreversible inhibition of nitrification and enhanced ammonia accumulation, causing a severe suppression of Nitrosomonas and an increase in the relative abundance of Nitrosospira. However, this increase not only affected ammonia oxidizers, but also caused a massive shift in denitrifying community structure, resulting in the suppression of Arenimonas metalli-, Candidatus Accumulibacter- and Sulfuritalea hydrogenivorans-nirS related genotypes and the predominance of nirS-associated with Acidovorax and Thaurea sp.
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Affiliation(s)
- Nikolaos Remmas
- Laboratory of Wastewater Management and Treatment Technologies, Department of Environmental Engineering, Democritus University of Thrace, Vas. Sofias 12, 67100 Xanthi, Greece
| | - Paraschos Melidis
- Laboratory of Wastewater Management and Treatment Technologies, Department of Environmental Engineering, Democritus University of Thrace, Vas. Sofias 12, 67100 Xanthi, Greece
| | - Efthymia Katsioupi
- Laboratory of Wastewater Management and Treatment Technologies, Department of Environmental Engineering, Democritus University of Thrace, Vas. Sofias 12, 67100 Xanthi, Greece
| | - Spyridon Ntougias
- Laboratory of Wastewater Management and Treatment Technologies, Department of Environmental Engineering, Democritus University of Thrace, Vas. Sofias 12, 67100 Xanthi, Greece.
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41
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Lv Y, Ju K, Wang L, Chen X, Miao R, Zhang X. Effect of pH on nitrous oxide production and emissions from a partial nitritation reactor under oxygen-limited conditions. Process Biochem 2016. [DOI: 10.1016/j.procbio.2016.02.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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42
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Xu W, Wu D, Wang J, Huang X, Xie B. Effects of oxygen and carbon content on nitrogen removal capacities in landfill bioreactors and response of microbial dynamics. Appl Microbiol Biotechnol 2016; 100:6427-6434. [PMID: 27005414 DOI: 10.1007/s00253-016-7460-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Revised: 03/08/2016] [Accepted: 03/09/2016] [Indexed: 10/22/2022]
Abstract
In this study, landfill bioreactors were tested to treat the recalcitrant leachate-nitrogen and the impacts of relevant operational parameters on its conversion were comprehensively investigated. We found that the highly diverse microbial community in landfill bioreactors could be substantially affected by increasing biodegradable carbon and oxygen content, which led to the whole system's intrinsic nitrogen removal capacity increasing from 50 to 70 %, and meanwhile, the contribution of anammox was detected less than 20 %. The sequencing and q-PCR results showed that microbial community in bioreactor was dominated by Proteobacteria (∼35 %) and Acidobacteria (~20 %) during the whole experiment. The abundance of anammox functioning bacteria (Amx) kept at a stable level (-2.5 to -2.2 log (copies/16S rRNA)) and was not statistically correlated to the abundance of anammox bacteria. However, significant linear correlation (p < 0.05) was determined between the abundance of nirS and Proteobacteria; amoA and AOB. Redundancy analysis (RDA) suggested that although oxygen and biodegradable carbon can both impose effects on microbial community structure, only biodegradable carbon content is the determinant in the total nitrogen removal.
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Affiliation(s)
- Weiqing Xu
- Key Laboratory for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Science; Joint Research Institute for New Energy and the Environment (East China Normal University and Colorado State University), East China Normal University, 500 Dong Chuan Road, Shanghai, 200241, People's Republic of China
| | - Dong Wu
- Key Laboratory for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Science; Joint Research Institute for New Energy and the Environment (East China Normal University and Colorado State University), East China Normal University, 500 Dong Chuan Road, Shanghai, 200241, People's Republic of China
| | - Jie Wang
- Key Laboratory for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Science; Joint Research Institute for New Energy and the Environment (East China Normal University and Colorado State University), East China Normal University, 500 Dong Chuan Road, Shanghai, 200241, People's Republic of China
| | - Xinghua Huang
- Key Laboratory for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Science; Joint Research Institute for New Energy and the Environment (East China Normal University and Colorado State University), East China Normal University, 500 Dong Chuan Road, Shanghai, 200241, People's Republic of China
| | - Bing Xie
- Key Laboratory for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Science; Joint Research Institute for New Energy and the Environment (East China Normal University and Colorado State University), East China Normal University, 500 Dong Chuan Road, Shanghai, 200241, People's Republic of China.
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43
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Zhang J, Jia W, Wang R, Ngo HH, Guo W, Xie H, Liang S. Microbial community characteristics during simultaneous nitrification-denitrification process: effect of COD/TP ratio. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2016; 23:2557-2565. [PMID: 26429138 DOI: 10.1007/s11356-015-5496-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Accepted: 09/22/2015] [Indexed: 06/05/2023]
Abstract
To evaluate the impact of chemical oxygen demand (COD)/total phosphorus (TP) ratio on microbial community characteristics during low-oxygen simultaneous nitrification and denitrification process, three anaerobic-aeration (low-oxygen) sequencing batch reactors, namely R1, R2, and R3, were performed under three different COD/TP ratios of 91.6, 40.8, and 27.6. The community structures of each reactor were analyzed via molecular biological technique. The results showed that the composition of ammonia-oxidizing bacteria (AOB) was affected, indicated by Shannon indexes of the samples from R1, R2, and R3. Nitrosomonas was identified to be the dominant AOB in all SBRs. Moreover, the copy numbers of nitrifiers were more than those of denitrifiers, and the phosphorus-accumulating organisms to glycogen-accumulating organisms ratio increased with the decrease of COD/TP ratio.
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Affiliation(s)
- Jian Zhang
- Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan, 250100, China
| | - Wenlin Jia
- School of Chemistry and Chemical Engineering, Jiangsu Normal University, Xuzhou, 221116, China
| | - Rong Wang
- Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan, 250100, China
| | - Huu Hao Ngo
- School of Civil and Environmental Engineering, University of Technology Sydney, Broadway, NSW 2007, Australia
| | - Wenshan Guo
- School of Civil and Environmental Engineering, University of Technology Sydney, Broadway, NSW 2007, Australia
| | - Huijun Xie
- Environmental Research Institute, Shandong University, Jinan, 250100, China
| | - Shuang Liang
- Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan, 250100, China.
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44
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Li X, Zhang M, Liu F, Li Y, He Y, Zhang S, Wu J. Abundance and distribution of microorganisms involved in denitrification in sediments of a Myriophyllum elatinoides purification system for treating swine wastewater. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2015; 22:17906-17916. [PMID: 26165997 DOI: 10.1007/s11356-015-5041-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Accepted: 07/05/2015] [Indexed: 06/04/2023]
Abstract
Environmental pollution from livestock production, particularly swine production, is often managed by the use of constructed wetlands, which incorporate plants such as Myriophyllum elatinoides as a means of treating wastewater. The M. elatinoides purification system has been shown to effectively remove, via nitrification and denitrification, more than 90% of the total nitrogen (TN) and 84% of the NH4 (+)-N produced in swine wastewater. However, the mechanisms of variation in aquatic environmental factors and how the interaction of these factors affects denitrification by microorganisms in sediments remain poorly understood. In this study, the impacts of dissolved oxygen (DO), TN, NH4(+)-N, and NO3(-)-N on the abundance, diversity, and community distribution of denitrifiers in the sediments from different concentrations and types of wastewater including tap water (CK), two strengths of synthetic wastewater: 200 mg NH4(+)-N L(-1) (T1) and 400 mg NH4(+)-N L(-1) (T2), swine wastewater diluted 50% (T3), and swine wastewater (T4) were investigated in a microcosm experiment. A significant improvement was observed in the abundance of denitrification genes (nirK and nirS) in response to increased NO3(-)-N and DO in the swine wastewater sediments. The abundance of these denitrification genes was highest in the T4 sediments compared with other treatments. Terminal restriction fragment length polymorphism (T-RFLP) analysis revealed that the DO, TN, and NH4(+)-N positively impacted the richness index (S) of the nirK denitrifiers in T1, whereas the NO3(-)-N negatively affected the Simpson diversity index (D) of nirK and nirS denitrifiers in T3 and T4. However, the NO3(-)-N positively affected the nirK and nirS denitrifier community distribution, whereas the DO negatively affected the nirK and nirS denitrifier distribution in T3 and T4. These findings will be helpful in that they allow us to recognize the effects of environmental factors on the formation of the denitrifiers in the sediments in a M. elatinoides purification system.
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Affiliation(s)
- Xi Li
- Key Laboratory of Agro-ecological Processes in Subtropical Regions, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Hunan, 410125, People's Republic of China
- Changsha Research Station for Agricultural and Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Hunan, 410125, People's Republic of China
| | - Miaomiao Zhang
- Key Laboratory of Agro-ecological Processes in Subtropical Regions, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Hunan, 410125, People's Republic of China
- Changsha Research Station for Agricultural and Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Hunan, 410125, People's Republic of China
| | - Feng Liu
- Key Laboratory of Agro-ecological Processes in Subtropical Regions, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Hunan, 410125, People's Republic of China.
- Changsha Research Station for Agricultural and Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Hunan, 410125, People's Republic of China.
| | - Yong Li
- Key Laboratory of Agro-ecological Processes in Subtropical Regions, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Hunan, 410125, People's Republic of China
- Changsha Research Station for Agricultural and Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Hunan, 410125, People's Republic of China
| | - Yang He
- Key Laboratory of Agro-ecological Processes in Subtropical Regions, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Hunan, 410125, People's Republic of China
- Changsha Research Station for Agricultural and Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Hunan, 410125, People's Republic of China
- Graduate University of Chinese Academy of Sciences, Beijing, 100039, People's Republic of China
| | - Shunan Zhang
- Key Laboratory of Agro-ecological Processes in Subtropical Regions, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Hunan, 410125, People's Republic of China
- Changsha Research Station for Agricultural and Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Hunan, 410125, People's Republic of China
- Graduate University of Chinese Academy of Sciences, Beijing, 100039, People's Republic of China
| | - Jinshui Wu
- Key Laboratory of Agro-ecological Processes in Subtropical Regions, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Hunan, 410125, People's Republic of China.
- Changsha Research Station for Agricultural and Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Hunan, 410125, People's Republic of China.
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45
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Sun L, Wang Z, Wei X, Li P, Zhang H, Li M, Li B, Wang S. Enhanced biological nitrogen and phosphorus removal using sequencing batch membrane-aerated biofilm reactor. Chem Eng Sci 2015. [DOI: 10.1016/j.ces.2015.07.033] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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46
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Miao L, Wang S, Li B, Cao T, Xue T, Peng Y. Advanced nitrogen removal via nitrite using stored polymers in a modified sequencing batch reactor treating landfill leachate. BIORESOURCE TECHNOLOGY 2015; 192:354-360. [PMID: 26056776 DOI: 10.1016/j.biortech.2015.05.013] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2015] [Revised: 05/05/2015] [Accepted: 05/07/2015] [Indexed: 06/04/2023]
Abstract
A modified sequencing batch reactor (SBR) operated at the anaerobic-aerobic-anoxic mode was developed in this study to fully utilize the organics in landfill leachate (ammonia concentration of 1000 ± 50 mg N/L and COD/total nitrogen (TN) ratio of 1-4). The unique feature of modified SBR process was the addition of an anaerobic stage after feeding stage, so that microorganisms could store the organics during anaerobic stage and supply the carbon source for endogenous denitritation after aeration stage. The 70-day operational tests showed the effluent TN was below 10 mg N/L at C/N ratio of 4. The intracellular stored polymers were analyzed and the microorganisms were capable of storing the carbon source as polyhydroxybutyrate (PHB) and glycogen in anaerobic stage, which were the electron donors for endogenous denitritation. Fluorescence in situ hybridization (FISH) analysis showed that glycogen accumulating organisms (GAOs) account for 39.8% of microorganisms in SBR, and carried out advanced nitrogen removal.
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Affiliation(s)
- Lei Miao
- Engineering Research Center of Beijing, Beijing University of Technology, Beijing, China.
| | - Shuying Wang
- Engineering Research Center of Beijing, Beijing University of Technology, Beijing, China
| | - Baikun Li
- Department of Civil and Environmental Engineering, University of Connecticut, Storrs, CT, USA
| | - Tianhao Cao
- Engineering Research Center of Beijing, Beijing University of Technology, Beijing, China
| | - Tonglai Xue
- Engineering Research Center of Beijing, Beijing University of Technology, Beijing, China
| | - Yongzhen Peng
- Engineering Research Center of Beijing, Beijing University of Technology, Beijing, China.
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47
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Herbert RB, Winbjörk H, Hellman M, Hallin S. Nitrogen removal and spatial distribution of denitrifier and anammox communities in a bioreactor for mine drainage treatment. WATER RESEARCH 2014; 66:350-360. [PMID: 25233117 DOI: 10.1016/j.watres.2014.08.038] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Revised: 07/15/2014] [Accepted: 08/23/2014] [Indexed: 06/03/2023]
Abstract
Mine drainage water may contain high levels of nitrate (NO3(-)) due to undetonated nitrogen-based explosives. The removal of NO3(-) and nitrite (NO2(-)) in cold climates through the microbial process of denitrification was evaluated using a pilot-scale fixed-bed bioreactor (27 m(3)). Surface water was diverted into the above-ground bioreactor filled with sawdust, crushed rock, and sewage sludge. At hydraulic residence times of ca.15 h and with the addition of acetate, NO3(-) and NO2(-) were removed to below detection levels at a NO3(-) removal rate of 5-10 g N m(-3) (bioreactor material) d(-1). The functional groups contributing to nitrogen removal in the bioreactor were studied by quantifying nirS and nirK present in denitrifying bacteria, nosZI and nosZII genes from the nitrous oxide - reducing community, and a taxa-specific part of the16S rRNA gene for the anammox community. The abundances of nirS and nirK were almost 2 orders of magnitude greater than the anammox specific 16S rRNA gene, indicating that denitrification was the main process involved in nitrogen removal. The spatial distribution of the quantified genes was heterogeneous in the bioreactor, with trends observed in gene abundance as a function of depth, distance from the bioreactor inlet, and along specific flowpaths. There was a significant relationship between the abundance of nirS, nirK, and nosZI genes and depth in the bioreactor, such that the abundance of organisms containing these genes may be controlled by oxygen diffusion and substrate supply in the partially or completely water-saturated material. Among the investigated microbial functional groups, nirS and anammox bacterial 16S rRNA genes exhibited a systematic trend of decreasing and increasing abundance, respectively, with distance from the inlet, which suggested that the functional groups respond differently to changing environmental conditions. The greater abundance of nirK along central flowpaths may indicate that the bioreactor design favored preferential flow along these flowpaths, away from the sides of the bioreactor. An improved bioreactor design should consider the role of preferential flowpaths and the heterogeneous distribution of the genetic potential for denitrification, nitrous oxide reduction and anammox on bioreactor function.
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Affiliation(s)
- Roger B Herbert
- Uppsala University, Department of Earth Sciences, Villavägen 16, SE-752 36 Uppsala, Sweden.
| | | | - Maria Hellman
- Swedish University of Agricultural Sciences, Department of Microbiology, Box 7025, SE-750 07 Uppsala, Sweden
| | - Sara Hallin
- Swedish University of Agricultural Sciences, Department of Microbiology, Box 7025, SE-750 07 Uppsala, Sweden
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48
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Gabarró J, González-Cárcamo P, Ruscalleda M, Ganigué R, Gich F, Balaguer MD, Colprim J. Anoxic phases are the main N2O contributor in partial nitritation reactors treating high nitrogen loads with alternate aeration. BIORESOURCE TECHNOLOGY 2014; 163:92-9. [PMID: 24787321 DOI: 10.1016/j.biortech.2014.04.019] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Revised: 03/31/2014] [Accepted: 04/05/2014] [Indexed: 05/20/2023]
Abstract
Partial nitritation (PN) reactors treating complex industrial wastewater can be operated by alternating anoxic-aerobic phases to promote heterotrophic denitrification via NO2(-). However, denitrification under stringent conditions can lead to high N2O production. In this study, the suitability of including anoxic phases in a PN-SBR treating real industrial wastewater was assessed in terms of process performance and N2O production. The PN-SBR was operated successfully and, when the HCO3(-):NH4(+) molar ratio was adjusted, produced a suitable effluent for a subsequent anammox reactor. 10-20% of the total influent nitrogen was removed. N2O production accounted for 3.6% of the NLR and took place mainly during the anoxic phases (60%). Specific denitrification batch tests demonstrated that, despite the availability of biodegradable COD, NO2(-) denitrification advanced at a faster rate than N2O denitrification, causing high N2O accumulation. Thus, the inclusion of anoxic phases should be avoided in PN reactors treating industrial wastewaters with high nitrogen loads.
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Affiliation(s)
- J Gabarró
- LEQUIA, Institute of the Environment, University of Girona, Campus Montilivi, E-17071 Girona, Catalonia, Spain
| | - P González-Cárcamo
- LEQUIA, Institute of the Environment, University of Girona, Campus Montilivi, E-17071 Girona, Catalonia, Spain
| | - M Ruscalleda
- LEQUIA, Institute of the Environment, University of Girona, Campus Montilivi, E-17071 Girona, Catalonia, Spain.
| | - R Ganigué
- LEQUIA, Institute of the Environment, University of Girona, Campus Montilivi, E-17071 Girona, Catalonia, Spain
| | - F Gich
- Group of Molecular Microbial Ecology, Institute of Aquatic Ecology (UdG), Campus Montilivi, E-17071 Girona, Catalonia, Spain
| | - M D Balaguer
- LEQUIA, Institute of the Environment, University of Girona, Campus Montilivi, E-17071 Girona, Catalonia, Spain
| | - J Colprim
- LEQUIA, Institute of the Environment, University of Girona, Campus Montilivi, E-17071 Girona, Catalonia, Spain
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