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Mancuso G, Foglia A, Chioggia F, Drei P, Eusebi AL, Lavrnić S, Siroli L, Carrozzini LM, Fatone F, Toscano A. Demo-scale up-flow anaerobic sludge blanket reactor coupled with hybrid constructed wetlands for energy-carbon efficient agricultural wastewater reuse in decentralized scenarios. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 359:121109. [PMID: 38723500 DOI: 10.1016/j.jenvman.2024.121109] [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: 02/10/2024] [Revised: 04/19/2024] [Accepted: 05/05/2024] [Indexed: 05/22/2024]
Abstract
The impact of climate change on water availability and quality has affected agricultural irrigation. The use of treated wastewater can alleviate water in agriculture. Nevertheless, it is imperative to ensure proper treatment of wastewater before reuse, in compliance with current regulations of this practice. In decentralized agricultural scenarios, the lack of adequate treatment facilities poses a challenge in providing treated wastewater for irrigation. Hence, there is a critical need to develop and implement innovative, feasible, and sustainable treatment solutions to secure the use of this alternative water source. This study proposes the integration of intensive treatment solutions and natural treatment systems, specifically, the combination of up-flow anaerobic sludge blanket reactor (UASB), anaerobic membrane bioreactor (AnMBR), constructed wetlands (CWs), and ultraviolet (UV) disinfection. For this purpose, a novel demo-scale plant was designed, constructed and implemented to test wastewater treatment and evaluate the capability of the proposed system to provide an effluent with a quality in compliance with the current European wastewater reuse regulatory framework. In addition, carbon-sequestration and energy analyses were conducted to assess the sustainability of the proposed treatment approach. This research confirmed that UASB rector can be employed for biogas production (2.5 L h-1) and energy recovery from organic matter degradation, but its effluent requires further treatment steps to be reused in agricultural irrigation. The AnMBR effluent complied with class A standards for E. coli, boasting a concentration of 0 CFU 100 mL-1, and nearly negligible TSS levels. However, further reduction of BOD5 (35 mg L-1) is required to reach water quality class A. CWs efficiently produced effluent with BOD5 below 10 mg L-1 and TSS close to 0 mg L-1, making it suitable for water reuse and meeting class A standards. Furthermore, CWs demonstrated significantly higher energy efficiency compared to intensive treatment systems. Nonetheless, the inclusion of a UV disinfection unit after CWs was required to attain water class B standards.
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Affiliation(s)
- Giuseppe Mancuso
- Alma Mater Studiorum - University of Bologna, Department of Agricultural and Food Sciences, Viale Fanin 50, 40127, Bologna, Italy.
| | - Alessia Foglia
- Marche Polytechnic University, Department of Science and Engineering of Materials, Environment and Urban Planning-SIMAU, Via Brecce Bianche, 12, Ancona, 60131, Italy.
| | - Francesco Chioggia
- Alma Mater Studiorum - University of Bologna, Department of Agricultural and Food Sciences, Viale Fanin 50, 40127, Bologna, Italy
| | - Pietro Drei
- Alma Mater Studiorum - University of Bologna, Department of Agricultural and Food Sciences, Viale Fanin 50, 40127, Bologna, Italy
| | - Anna Laura Eusebi
- Marche Polytechnic University, Department of Science and Engineering of Materials, Environment and Urban Planning-SIMAU, Via Brecce Bianche, 12, Ancona, 60131, Italy
| | - Stevo Lavrnić
- Alma Mater Studiorum - University of Bologna, Department of Agricultural and Food Sciences, Viale Fanin 50, 40127, Bologna, Italy
| | - Lorenzo Siroli
- Alma Mater Studiorum - University of Bologna, Department of Agricultural and Food Sciences, Viale Fanin 50, 40127, Bologna, Italy
| | | | - Francesco Fatone
- Marche Polytechnic University, Department of Science and Engineering of Materials, Environment and Urban Planning-SIMAU, Via Brecce Bianche, 12, Ancona, 60131, Italy
| | - Attilio Toscano
- Alma Mater Studiorum - University of Bologna, Department of Agricultural and Food Sciences, Viale Fanin 50, 40127, Bologna, Italy
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2
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Fan Y, Sun S, Gu X, Zhang M, Peng Y, Yan P, He S. Boosting the denitrification efficiency of iron-based constructed wetlands in-situ via plant biomass-derived biochar: Intensified iron redox cycle and microbial responses. WATER RESEARCH 2024; 253:121285. [PMID: 38354664 DOI: 10.1016/j.watres.2024.121285] [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: 12/05/2023] [Revised: 01/22/2024] [Accepted: 02/06/2024] [Indexed: 02/16/2024]
Abstract
Considering the unsatisfied denitrification performance of carbon-limited wastewater in iron-based constructed wetlands (ICWs) caused by low electron transfer efficiency of iron substrates, utilization of plant-based conductive materials in-situ for improving the long-term reactivity of iron substrates was proposed to boost the Fe (III)/Fe (II) redox cycle thus enhance the nitrogen elimination. Here, we investigated the effects of withered Iris Pseudacorus biomass and its derived biochar on nitrogen removal for 165 days in ICWs. Results revealed that accumulate TN removal capacity in biochar-added ICW (BC-ICW) increased by 14.7 % compared to biomass-added ICW (BM-ICW), which was mainly attributed to the synergistic strengthening of iron scraps and biochar. The denitrification efficiency of BM-ICW improved by 11.6 % compared to ICWs, while its removal capacity declined with biomass consumption. Autotrophic and heterotrophic denitrifiers were enriched in BM-ICW and BC-ICW, especially biochar increased the abundance of electroactive species (Geobacter and Shewanella, etc.). An active iron cycle exhibited in BC-ICW, which can be confirmed by the presence of more liable iron minerals on iron scraps surface, the lowest Fe (III)/Fe (II) ratio (0.51), and the improved proportions of iron cycling genes (feoABC, korB, fhuF, TC.FEV.OM, etc.). The nitrate removal efficiency was positively correlated with the nitrogen, iron metabolism functional genes and the electron transfer capacity (ETC) of carbon materials (P < 0.05), indicating that redox-active carbon materials addition improved the iron scraps bioavailability by promoting electron transfer, thus enhancing the autotrophic nitrogen removal. Our findings provided a green perspective to better understand the redox properties of plant-based carbon materials in ICWs for deep bioremediation in-situ.
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Affiliation(s)
- Yuanyuan Fan
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, PR China
| | - Shanshan Sun
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, PR China
| | - Xushun Gu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, PR China
| | - Manping Zhang
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, PR China
| | - Yuanyuan Peng
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, PR China
| | - Pan Yan
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, PR China
| | - Shengbing He
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, PR China.
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3
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Zhang L, Cao Z, Yan B, Li Z, Pan J, Fan L. How do aeration mode and influent carbon/nitrogen ratio affect pollutant removal, gas emission, functional genes and bacterial community in subsurface wastewater infiltration systems? WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2023; 88:2793-2808. [PMID: 38096069 PMCID: wst_2023_383 DOI: 10.2166/wst.2023.383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2023]
Abstract
This study investigated the influences of aeration mode and influent carbon/nitrogen ratio on matrix oxygen concentration, pollutant removal, greenhouse gas emission, functional gene abundances and bacterial community in subsurface wastewater infiltration systems (SWISs). Intermittent or continuous aeration enhanced oxygen supply at 0.6 m depth in the matrix, which improved organics removal, nitrogen removal, the abundances of bacterial 16S rRNA, amoA, nxrA, narG, napA, nirK, nirS, norB, nosZ genes, bacterial community Alpha diversity, the relative abundances of Actinobacteria at 0.6 m depth, the relative abundances of Chloroflexi, Gemmatimonadetes, Bacteroidetes and Firmicutes at 0.9 and 1.2 m depth and reduced CH4 and N2O conversion efficiencies, the abundance of mcrA gene with carbon/nitrogen ratio of 12 and 16 compared with non-aeration. Increased carbon/nitrogen ratio resulted in higher TN removal efficiencies and lower CH4 and N2O conversion efficiencies in aeration SWISs than those in non-aeration SWIS. Intermittent aeration SWIS obtained high removal efficiencies of 83.2, 85.4 and 90.8% for TN, NH4+ -N and COD and low conversion efficiency of 0.21 and 0.65% for N2O and CH4 with optimal carbon/nitrogen ratio of 12. However, high TN (82.6%), NH4+ -N (84.9%) and COD (92.2%) removal efficiencies and low CH4 (0.67%) and N2O (0.23%) conversion efficiencies were achieved in continuous aeration SWIS with carbon/nitrogen ratio of 16.
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Affiliation(s)
- Lei Zhang
- These authors contributed equally to this study and share first authorship. E-mail:
| | - Zhixi Cao
- These authors contributed equally to this study and share first authorship
| | - Bingqian Yan
- These authors contributed equally to this study and share first authorship
| | - Ziqi Li
- These authors contributed equally to this study and share first authorship
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4
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Lu J, Dong L, Guo Z, Hu Z, Dai P, Zhang J, Wu H. Highly efficient phosphorous removal in constructed wetland with iron scrap: Insights into the microbial removal mechanism. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 347:119076. [PMID: 37748299 DOI: 10.1016/j.jenvman.2023.119076] [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: 07/16/2023] [Revised: 08/30/2023] [Accepted: 09/13/2023] [Indexed: 09/27/2023]
Abstract
Excessive phosphorus (P) in surface water can lead to serious eutrophication and economic losses. Iron-based constructed wetland (CW) is considered as a promising solution to eliminate P effectively due to the advantage of low-cost. However, there is limited available information on the microbial removal mechanism of P in iron-based CW up to now. Therefore, CW with iron scrap was constructed to investigate the treatment performance and microbial removal mechanism in this study. Results showed that efficient and stable P removal (97.09 ± 1.90%) was achieved in iron scrap-based CW during the experiment period, which was attributed to the precipitation of iron and P and improved microbially mediated P removal. Metagenomic analysis showed that microbial diversity was enhanced and phosphate accumulating organisms (e.g., Dechloromonas and Tetrasphaera) were enriched in CW with iron scrap, which explained higher P removal reasonably. In addition, the abundance of genes involved in the P starvation (e.g., phoB), uptake and transport (e.g., pstB) were enhanced in iron scrap-based CW. Enrichment analysis demonstrated that phosphotransferase pathway was also significantly up-regulated in CW with iron scraps, indicating that the energy supply of microbial P removal was enhanced. These findings provide a better understanding of the microbial removal mechanism of P in iron-based CW.
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Affiliation(s)
- Jiaxing Lu
- School of Environmental Science & Engineering, Shandong University, Qingdao, 266237, PR China
| | - Lu Dong
- School of Environment, Beijing Normal University, Beijing, 100875, PR China
| | - Zizhang Guo
- School of Environmental Science & Engineering, Shandong University, Qingdao, 266237, PR China.
| | - Zhen Hu
- School of Environmental Science & Engineering, Shandong University, Qingdao, 266237, PR China
| | - Peng Dai
- Department of Civil & Environmental Engineering, South Dakota State University Brookings, South Dakota, 57007, United States
| | - Jian Zhang
- School of Environmental Science & Engineering, Shandong University, Qingdao, 266237, PR China
| | - Haiming Wu
- School of Environmental Science & Engineering, Shandong University, Qingdao, 266237, PR China.
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5
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Jiang W, Yao X, Wang F, Li Y, Zhu S, Bian D. Effect of transient organic load and aeration changes to pollutant removal and extracellular polymeric substances. ENVIRONMENTAL TECHNOLOGY 2023; 44:2417-2430. [PMID: 35029133 DOI: 10.1080/09593330.2022.2029952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 01/08/2022] [Indexed: 06/08/2023]
Abstract
Transient organic load shocks have an important influence on the removal of pollutants and the content and composition of extracellular polymeric substances (EPS). This study was based on a micro-pressure reactor (MPR) with the influent COD concentration as the variable, while different operating conditions were controlled by adjusting the aeration rate. The effect of single-cycle transient organic loading shocks on EPS and pollutant removal and the correlation between their changes were investigated. The results showed that COD removal was unaffected under the shock, and the effect of nitrogen and phosphorus removal decreased. As the incoming carbon source increased, the EPS content at shock increased, with the polysaccharide (PS) content being the most affected. As aeration increased, the effect of organic load shock on EPS and pollutant removal decreased. Under different aeration conditions, PS contributed to denitrification and anaerobic phosphorus release during transient organic load shocks, and protein (PN) contributed to aerobic phosphorus uptake. The reduction in PS and PN relative to the pre-shock caused by the shock resulted in the EPS exhibiting a favourable effect on COD removal and an inhibitory effect on the effectiveness of nitrogen and phosphorus removal.
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Affiliation(s)
- Weiqing Jiang
- Jilin Provincial Key Laboratory of Municipal Wastewater Treatment, Changchun Institute of Technology, Changchun, People's Republic of China
| | - Xingrong Yao
- Jilin Provincial Key Laboratory of Municipal Wastewater Treatment, Changchun Institute of Technology, Changchun, People's Republic of China
| | - Fan Wang
- Jilin Provincial Key Laboratory of Municipal Wastewater Treatment, Changchun Institute of Technology, Changchun, People's Republic of China
| | - Yajing Li
- Jilin Provincial Key Laboratory of Municipal Wastewater Treatment, Changchun Institute of Technology, Changchun, People's Republic of China
| | - Suiyi Zhu
- Jilin Provincial Key Laboratory of Municipal Wastewater Treatment, Changchun Institute of Technology, Changchun, People's Republic of China
- Science and Technology Innovation Center for Municipal Wastewater Treatment and Water Quality Protection, Northeast Normal University, Changchun, People's Republic of China
| | - Dejun Bian
- Jilin Provincial Key Laboratory of Municipal Wastewater Treatment, Changchun Institute of Technology, Changchun, People's Republic of China
- Science and Technology Innovation Center for Municipal Wastewater Treatment and Water Quality Protection, Northeast Normal University, Changchun, People's Republic of China
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6
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Khan HIUH, Mehta N, Zhang X, Rousseau DPL, Ronsse F. Assessment of the properties of aging biochar used as a substrate in constructed wetlands. CHEMOSPHERE 2023; 334:138999. [PMID: 37217009 DOI: 10.1016/j.chemosphere.2023.138999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 05/03/2023] [Accepted: 05/19/2023] [Indexed: 05/24/2023]
Abstract
Biochar has gained global recognition as an effective tool for environmental remediation, and is increasingly being used as an alternative substrate in constructed wetlands (CWs). While, most studies have focused on the positive effects of biochar for the pollutant removal in CWs, less is known about aging and longevity of the embedded biochar. This study investigated the aging and stability of biochar embedded in CWs post-treating the effluent of a municipal and an industrial wastewater treatment plant. Litter bags containing biochar were inserted into two aerated horizontal subsurface flow CWs (350 m2 each), and retrieved on several dates (8-775 days after burial) for assessment of weight loss/gain and changes in biochar characteristics. Additionally, a 525-day laboratory incubation test was conducted to analyze biochar mineralization. The results showed that there was no significant biochar weight loss over time, but a slight increase in weight (2.3-3.0%) was observed at the end, likely due to mineral sorption. Biochar pH remained stable except for a sudden drop at the beginning (8.6-8.1), while the electrical conductivity continued to increase (96-256 μS cm-1) throughout the experiment. The sorption capacity of the aged biochar for methylene blue significantly increased (1.0-1.7 mg g-1), and a change in the biochar's elemental composition was also noted, with O-content increasing by 13-61% and C content decreasing by 4-7%. Despite these changes, the biochar remained stable according to the criteria of the European Biochar Foundation and International Biochar Initiative. The incubation test also showed negligible biochar mass loss (<0.02%), further validating the stability of the biochar. This study provides important insights into the evolution of biochar characteristics in CWs.
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Affiliation(s)
- Hafiz Ihsan Ul-Haq Khan
- Laboratory for Industrial Water and Ecotechnology (LIWET), Department of Green Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University Campus Kortrijk, Sint-Martens-Latemlaan 2B, B-8500, Kortrijk, Belgium.
| | - Nisarg Mehta
- Department of Air Protection, Faculty of Energy and Environmental Engineering, Silesian University of Technology, Gliwice, Poland
| | - Xian Zhang
- Laboratory for Industrial Water and Ecotechnology (LIWET), Department of Green Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University Campus Kortrijk, Sint-Martens-Latemlaan 2B, B-8500, Kortrijk, Belgium
| | - Diederik P L Rousseau
- Laboratory for Industrial Water and Ecotechnology (LIWET), Department of Green Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University Campus Kortrijk, Sint-Martens-Latemlaan 2B, B-8500, Kortrijk, Belgium
| | - Frederik Ronsse
- Thermochemical Conversion of Biomass (TCCB), Department of Green Chemistry and Technology, Faculty of Bioscience Engineering, Coupure Links 653, 9000, Gent, Belgium
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7
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Wang X, Wang J, Chen J, Chen J, Lv Y, Chen R, Xu J, Li D, He X, Hou J. Formation of microorganism-derived dissolved organic nitrogen in intermittent aeration constructed wetland and its stimulating effect on phytoplankton production: Implications for nitrogen mitigation. WATER RESEARCH 2023; 230:119563. [PMID: 36621276 DOI: 10.1016/j.watres.2022.119563] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 11/25/2022] [Accepted: 12/31/2022] [Indexed: 06/17/2023]
Abstract
To control eutrophication in aquatic ecosystems, enhancing nitrogen removal in the constructed wetland (CW) by upgrading conventional CW to aeration CW is commonplace. However, regulatory efforts have only focused on reducing dissolved inorganic nitrogen (DIN) discharge and disregarding dissolved organic nitrogen (DON). Here, we used experimental mesocosms to investigate the effect of aeration mode on the characteristics of effluent DON in CW. The results showed that intermittent aeration is prone to introduce large amounts of DON and bioavailable DON (ABDON) in the effluents, although it greatly decreases effluent total nitrogen (TN). Analysis of DON fluorescent components and molecular characteristics indicated that suddenly shifting the environment from anoxic condition to aerobic condition in the intermittent aeration CW (IACW) would stimulate microorganisms to release tryptophan and simple aromatic proteins-like substances, which does not occur in the limited continuous aeration CW (CACW). Consequently, the abundance of DON resembling lipids, proteins/amino sugars, and carbohydrates-like molecules in IACW were about 2.1 times higher than that in CACW. Bioassay results showed that Selenastrum capricornutum and Microcystis aeruginosa incubated with effluent from IACW both generate larger phytoplankton biomass than that with CACW effluent, even though IACW effluent contains less TN than its counterpart. Moreover, Microcystis aeruginosa can simultaneously utilize DON and DIN, while Selenastrum capricornutum seem to utilize the DON only when DIN was not available. This result implies that increasing DON discharge may also influence phytoplankton composition and stimulate harmful phytoplankton species. Overall, this study indicates that upgrading CW solely depending on DIN removal level cannot ensure a mitigation of nitrogen-related eutrophication, and more efforts should be paid to curb DON discharge.
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Affiliation(s)
- Xiaoning Wang
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China
| | - Jie Wang
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China
| | - Jingyi Chen
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China
| | - Jieyu Chen
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China
| | - Yabing Lv
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China
| | - Ruiya Chen
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China
| | - Juchen Xu
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China
| | - Dapeng Li
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China; Engineering Research Center of Green Development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt, Ministry of Education, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan 430070, China
| | - Xugang He
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China; Engineering Research Center of Green Development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt, Ministry of Education, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan 430070, China.
| | - Jie Hou
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China; Engineering Research Center of Green Development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt, Ministry of Education, Wuhan 430070, China; Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, Wuhan 430070, China.
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8
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Kadam R, Khanthong K, Park B, Jun H, Park J. Realizable wastewater treatment process for carbon neutrality and energy sustainability: A review. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 328:116927. [PMID: 36473349 DOI: 10.1016/j.jenvman.2022.116927] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 10/29/2022] [Accepted: 11/27/2022] [Indexed: 06/17/2023]
Abstract
Despite a quick shift of global goals toward carbon-neutral infrastructure, activated sludge based conventional systems inhibit the Green New Deal. Here, a municipal wastewater treatment plant (MWWTP) for carbon neutrality and energy sustainability is suggested and discussed based on realizable technical aspects. Organics have been recovered using variously enhanced primary treatment techniques, thereby reducing oxygen demand for the oxidation of organics and maximizing biogas production in biological processes. Meanwhile, ammonium in organic-separated wastewater is bio-electrochemically oxidized to N2 and reduced to H2 under completely anaerobic conditions, resulting in the minimization of energy requirements and waste sludge production, which are the main problems in activated sludge based conventional processes. The anaerobic digestion process converts concentrated primary sludge to biomethane, and H2 gas recovered from nitrogen upgrades the biomethane quality by reducing carbon dioxide in biogas. Based on these results, MWWTPs can be simplified and improved with high process and energy efficiencies.
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Affiliation(s)
- Rahul Kadam
- Department of Advanced Energy Engineering, Chosun University, Gwangju, 61452, Republic of Korea
| | - Kamonwan Khanthong
- Department of Advanced Energy Engineering, Chosun University, Gwangju, 61452, Republic of Korea
| | - Byeongchang Park
- Department of Environmental Engineering, Chungbuk National University, Cheongju, 28644, Republic of Korea
| | - Hangbae Jun
- Department of Environmental Engineering, Chungbuk National University, Cheongju, 28644, Republic of Korea
| | - Jungyu Park
- Department of Advanced Energy Engineering, Chosun University, Gwangju, 61452, Republic of Korea.
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9
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Xu W, Yang B, Wang H, Wang S, Jiao K, Zhang C, Li F, Wang H. Improving the removal efficiency of nitrogen and organics in vertical-flow constructed wetlands: the correlation of substrate, aeration and microbial activity. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:21683-21693. [PMID: 36274076 DOI: 10.1007/s11356-022-23746-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Accepted: 10/17/2022] [Indexed: 06/16/2023]
Abstract
Four vertical-flow CWs (VFCWs) with different substrates and aeration conditions were studied on nutrient-removal capacity from synthetic wastewater. Zeolite substrate VFCWs (none-aerated: VFCW-1, aerated: VFCW-3) paralleled with ceramsite (none-aerated:VFCW-2, aerated: VFCW-4) were used to study the removal efficiencies of N and organics, the bacterial community, and the related functional genes. The results indicated that the pollutant removal efficiency was significantly enhanced by intermittent aeration. VFCW-4 (ceramsite with aeration) demonstrated a significant potential to remove NH4+-N (89%), NO3--N (78%), TN (71%), and COD (65%). VFCW-3 and VFCW-4 had high abundances of Amx, amoA, and nirK genes, which was related to NH4+-N and NO2--N removal. The microbial diversity and structure varied with aeration and substrate conditions. Proteobacteria, Actinobacteria, Candidatus, and Acidobacteria were the main bacteria phyla, with the average proportion of 38%, 21%, 19%, and 7% in the VFCWs. Intermittent aeration increased the abundance of Acidobacteria, which was conducive to the removal of organic matters. Overall, ceramsite substrate combined with intermittent aeration has a great potential in removing pollutants in VFCWs.
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Affiliation(s)
- Wenxue Xu
- School of Water Conservancy and Environment, University of Jinan, Jinan, 250022, China
| | - Baoshan Yang
- School of Water Conservancy and Environment, University of Jinan, Jinan, 250022, China
- Shandong Provincial Engineering Technology Research Center for Ecological Carbon Sink and Capture Utilization, Jinan, 250022, China
| | - Hui Wang
- School of Water Conservancy and Environment, University of Jinan, Jinan, 250022, China.
- Shandong Provincial Engineering Technology Research Center for Ecological Carbon Sink and Capture Utilization, Jinan, 250022, China.
| | - Shuzhi Wang
- School of Water Conservancy and Environment, University of Jinan, Jinan, 250022, China
| | - Keqin Jiao
- School of Water Conservancy and Environment, University of Jinan, Jinan, 250022, China
| | - Chuanfeng Zhang
- School of Water Conservancy and Environment, University of Jinan, Jinan, 250022, China
| | - Feng Li
- School of Water Conservancy and Environment, University of Jinan, Jinan, 250022, China
| | - Haixia Wang
- School of Water Conservancy and Environment, University of Jinan, Jinan, 250022, China
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10
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Jin F, Hu Z, Liu H, Su J, Zhang J, Wang S, Zhao Y. Impact of clogging on accumulation and stability of phosphorus in the subsurface flow constructed wetland. CHEMOSPHERE 2023; 313:137429. [PMID: 36462565 DOI: 10.1016/j.chemosphere.2022.137429] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 11/14/2022] [Accepted: 11/27/2022] [Indexed: 06/17/2023]
Abstract
Substrate clogging is one of the major operation challenges of subsurface flow constructed wetlands (SSF-CWs). And the phosphorus (P) removal performance and stability of P accumulation of SSF-CWs would be varied with the development of substrate clogging. In this study, three horizontal SSF-CWs microcosms with different clogging degrees were conducted to explore the mechanism of P accumulation behavior influenced by substrate clogging. Increase in clogging degree resulted in hydraulic retention time (HRT) diminution and adsorption sites increase, which jointly led to reduced P removal efficiency at low clogging degree (L-CW), however, higher P removal efficiency was obtained as adsorption sites increase offset HRT diminution at high clogging degree (H-CW). Substrate adsorption was the primary removal pathway in all SSF-CW systems. It accounted for 77.86 ± 2.63% of the P input in the H-CW, significantly higher than the control (60.08 ± 4.79%). This was attributed to a higher proportion of Fe/Al-P accumulated on the substrate of H-CW, since clogging aggravated the anaerobic condition and promoted the generation of Fe ions. The increase in clogging degree also elevated the release risk of the accrued P in SSF-CWs, since Fe/Al-P was considered bioavailable and readily released under environmental disturbance. The obtained results provide new insights into the P transport and transformation in SSF-CWs and would be helpful to optimize substrate clogging management.
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Affiliation(s)
- Fenglin Jin
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science & Engineering, Shandong University, Qingdao 266237, PR China
| | - Zhen Hu
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science & Engineering, Shandong University, Qingdao 266237, PR China.
| | - Huaqing Liu
- College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao 266590, China
| | - Jixin Su
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science & Engineering, Shandong University, Qingdao 266237, PR China
| | - Jian Zhang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science & Engineering, Shandong University, Qingdao 266237, PR China; College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao 266590, China
| | - Shuo Wang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science & Engineering, Shandong University, Qingdao 266237, PR China
| | - Yanhui Zhao
- Field Monitoring Station of the Ministry of Education for the East Route of the South-to-North Water Transfer Project, Shandong University, Jinan 250100, PR China
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11
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Niu Y, Qu M, Du J, Wang X, Yuan S, Zhang L, Zhao J, Jin B, Wu H, Wu S, Cao X, Pang L. Effects of multiple key factors on the performance of petroleum coke-based constructed wetland-microbial fuel cell. CHEMOSPHERE 2023; 315:137780. [PMID: 36623598 DOI: 10.1016/j.chemosphere.2023.137780] [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: 10/27/2022] [Revised: 01/03/2023] [Accepted: 01/05/2023] [Indexed: 06/17/2023]
Abstract
In this study, two constructed wetland-microbial fuel cells (CW-MFC), including a closed-circuit system (CCW-MFC) and an open-circuit system (OCW-MFC) with petroleum coke as electrode and substrate, were constructed to explore the effect of multiple key factors on their operation performances. Compared to a traditional CW, the CCW-MFC system showed better performance, achieving an average removal efficiency of COD, NH4+-N, and TN of 94.49 ± 1.81%, 94.99 ± 4.81%, and 84.67 ± 5.6%, respectively, when the aeration rate, COD concentration, and hydraulic retention time were 0.4 L/min, 300 mg/L, and 3 days. The maximum output voltage (425.2 mV) of the CCW-MFC system was achieved when the aeration rate was 0.2 L/min. In addition, the CCW-MFC system showed a greater denitrification ability due to the higher abundance of Thiothrix that might attract other denitrifying bacteria, such as Methylotenera and Hyphomicrobium, to participate in the denitrifying process, indicating the quorum sensing could be stimulated within the denitrifying microbial community.
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Affiliation(s)
- Yulong Niu
- School of Materials and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou, China
| | - Mingxiang Qu
- School of Materials and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou, China
| | - Jingjing Du
- School of Materials and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou, China; Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, Henan, China.
| | - Xilin Wang
- School of Materials and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou, China
| | - Shuaikang Yuan
- School of Materials and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou, China
| | - Lingyan Zhang
- School of Materials and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou, China
| | - Jianguo Zhao
- School of Materials and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou, China; Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, Henan, China
| | - Baodan Jin
- School of Materials and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou, China; Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, Henan, China
| | - Haiming Wu
- School of Environmental Science & Engineering, Shandong University, Qingdao, China
| | - Shubiao Wu
- Department of Agroecology, Aarhus University, Tjele, Denmark
| | - Xia Cao
- School of Materials and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou, China; Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, Henan, China.
| | - Long Pang
- School of Materials and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou, China; Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, Henan, China
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12
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Allen DJ, Farrell M, Huang J, Plush S, Mosley LM. Artificial aeration of an overloaded constructed wetland improves hypoxia but does not ameliorate high nitrogen loads. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 326:116625. [PMID: 36356541 DOI: 10.1016/j.jenvman.2022.116625] [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: 06/17/2022] [Revised: 10/04/2022] [Accepted: 10/23/2022] [Indexed: 06/16/2023]
Abstract
High organic loadings to constructed wetlands can result in water quality issues such as low dissolved oxygen and high ammonium concentrations, with artificial aeration a potential mitigation option. This study compared baseline (no aeration - NA), continuous aeration (CA), and intermittent aeration (IA) conditions to improve water quality in a tertiary treatment free water surface constructed wetland (FWS CW) with night time hypoxia/anoxia, and high nutrient concentrations. The response variables included dissolved oxygen (DO), total nitrogen (TN), ammonium nitrogen (NH4+-N), nitrate nitrogen (NO3--N), total phosphorus (TP), phosphate (PO43--P), and dissolved organic carbon (DOC). In situ aeration and monitoring was performed from April to June 2021 in a large, field-scale FWS CW, the Laratinga wetlands Mount Barker, South Australia. The results demonstrated that DO increased by an average 2.11 mg L-1 from NA to CA during the night and 1.26 mg L-1 and 1.84 mg L-1 from NA to IA during the night and day respectively when averaging over the basins. The C/N ratio was very low and there was no significant influence of DO on DOC concentrations. There was no significant difference in TN concentrations with the application of aeration aside from a decrease in the channel at night from NA to IA, and an increase in NH4+-N resulted under IA compared with NA in Basin 1 and 2 during the day. This implies that the N loadings exceeded the wetland's ability to complete nutrient conversions at a rate that aligns with input rate. The concentrations of NO3--N increased at night under CA and IA treatments suggesting that some nitrification was promoted, or there was inhibition of dissimilatory nitrate reduction to ammonium. The concentrations of TP and PO43--P significantly increased with the aeration compared with no aeration, however there was no difference between the aeration treatments. This suggested that increased sediment resuspension during aeration increased P in the water. There was no change in DOC with the application of aeration. Overall, the DO increased with aeration application and may be able to better support the wetland ecology; however, the Laratinga wetland is overloaded and the capacity of the wetland to effectively transform and remove nutrients is inhibited, even with the application of artificial aeration.
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Affiliation(s)
- Danielle J Allen
- School of Biological Sciences, University of Adelaide, Kaurna Country, Urrbrae, South Australia 5064, Australia; CSIRO Agriculture & Food, Kaurna Country, Gate 4 Waite Road, Urrbrae, South Australia 5064, Australia
| | - Mark Farrell
- CSIRO Agriculture & Food, Kaurna Country, Gate 4 Waite Road, Urrbrae, South Australia 5064, Australia
| | - Jianyin Huang
- Scarce Resources and Circular Economy (ScaRCE) University of South Australia, Mawson Lakes Blvd, Kaurna Country, Mawson Lakes, South Australia 5095, Australia
| | - Simon Plush
- Mount Barker District Council, 6 Dutton Road, Peramangk Country, Mount Barker, South Australia 5251, Australia
| | - Luke M Mosley
- School of Biological Sciences, University of Adelaide, Kaurna Country, Urrbrae, South Australia 5064, Australia; School of Agriculture Food and Wine, University of Adelaide, Kaurna Country, Urrbrae, South Australia 5064, Australia.
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13
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Zeng F, Xie Y, Guo Y, Li Q, Tan B, Huang F, Huang Y, Ni S, Xu J, Jia J. Demonstration study of bypass multipond wetland system to enhance river water quality. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2022; 86:1745-1758. [PMID: 36240309 DOI: 10.2166/wst.2022.295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
This study focused on the water quality of a river in Wuhan City, China, which is surrounded by ponds that were transformed into a bypass multipond wetland system to improve river water quality. The bypass multipond wetland system included surface-flow artificial wetlands, modified partition ponds, aeration reoxygenation ponds, ecological ponds, and other processes. After the stable operation of the process, the water transparency was higher than 60 cm and the dissolved oxygen (DO) was higher than 5 mg/L, while the ammonia nitrogen (NH3-N) concentration was less than 1.0 mg/L, total phosphorus (TP) was lower than 0.2 mg/L, and chemical oxygen demand (COD) was lower than 20 mg/L, achieving the treatment target. After monitoring the results of each process, the process which best enhanced the water transparency enhancement was the surface-flow of the artificial wetlands and ecological ponds. The aeration reoxygenation pond had the best effect on DO enhancement. The processes that most affected NH3-N and TP removal were the surface-flow artificial wetlands and ecological ponds. The modified parthenogenic pond had the greatest effect on COD removal. The bypass multipond wetland system not only improved the river water quality but also enhanced the river landscape, and can act as a reference for similar river water quality improvement actions.
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Affiliation(s)
- Fanhu Zeng
- China First Metallurgical Group Co., Ltd., Wuhan 430080, China
| | - Yu Xie
- China First Metallurgical Group Co., Ltd., Wuhan 430080, China
| | - Yuping Guo
- China First Metallurgical Group Co., Ltd., Wuhan 430080, China
| | - Qigao Li
- China First Metallurgical Group Co., Ltd., Wuhan 430080, China
| | - Bin Tan
- China First Metallurgical Group Co., Ltd., Wuhan 430080, China
| | - Fuyao Huang
- Wuhan University of Technology, Wuhan 430070, China E-mail:
| | - Yongbing Huang
- Wuhan University of Technology, Wuhan 430070, China E-mail:
| | - Shang Ni
- Wuhan University of Technology, Wuhan 430070, China E-mail:
| | - Jiefei Xu
- Wuhan University of Technology, Wuhan 430070, China E-mail:
| | - Junzuo Jia
- Wuhan University of Technology, Wuhan 430070, China E-mail:
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14
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Li M, Ge S, Zhang J, Wu S, Wu H, Zhuang LL. Mechanism and performance of algal pond assisted constructed wetlands for wastewater polishing and nutrient recovery. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 840:156667. [PMID: 35705127 DOI: 10.1016/j.scitotenv.2022.156667] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 05/30/2022] [Accepted: 06/09/2022] [Indexed: 06/15/2023]
Abstract
The limitation of oxygen and carbon source restricted the TN removal in constructed wetland (CW). Algal pond (AP) could produce oxygen and fix CO2 to improve C/N ratio in water. Therefore, an AP-CW system was established under laboratory conditions to deeply explore the effect of nutrient load distribution and microalgae addition in CWs on pollutant removal. This study showed that AP-CW could remove 49.7% TN and 90.0% TP with no carbon addition in CWs. The significant removal of NH4-N by AP advanced the location of denitrification in CWs. To enhance TN removal, different dosage of microalgae were intermittently added at 20 and 10 cm respectively below the inlet of the vertical flow CW1 and CW2, where the rest NH4-N has been almost oxidized into nitrate. The addition of microalgae influenced the microflora and effluent quality. Microalgae dosage in denitrification area significantly increased the absolute abundance of Σnir. The best TN removal of AP-CW could reach 91.3% when 8 g (dry weight) microalgae was added. However, unlike previous knowledge, microalgae as an organic carbon source would also release N and P during decomposition, leading to increased nutrients in the effluent. The optimal dosage of microalgae was 1 g/5 d in this study. The position and amount of microalgae addition in CWs should be adjusted based on water property and element flow to achieve the best pollutant removal and biomass harvest.
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Affiliation(s)
- Mengting Li
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science & Engineering, Shandong University, Qingdao 266237, China
| | - Shuhan Ge
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science & Engineering, Shandong University, Qingdao 266237, China
| | - Jian Zhang
- College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao 266590, China; Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science & Engineering, Shandong University, Qingdao 266237, China
| | - Shubiao Wu
- Department of Agroecology, Aarhus University, Blichers All'e 20, 8830 Tjele, Denmark
| | - Haiming Wu
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science & Engineering, Shandong University, Qingdao 266237, China
| | - Lin-Lan Zhuang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science & Engineering, Shandong University, Qingdao 266237, China.
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15
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Chen Y, Zhang J, Guo Z, Li M, Wu H. Optimizing agricultural biomass application to enhance nitrogen removal in vertical flow constructed wetlands for treating low-carbon wastewater. ENVIRONMENTAL RESEARCH 2022; 209:112867. [PMID: 35131325 DOI: 10.1016/j.envres.2022.112867] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 01/10/2022] [Accepted: 01/28/2022] [Indexed: 06/14/2023]
Abstract
Agricultural biomass waste in rural areas has been identified as an economical solid carbon sources in constructed wetlands (CWs) for treating low C/N ratio domestic sewage. However, little information is available regarding its optimal utilization as a media amendment for enhancing nitrogen removal in CWs. In this study, vertical flow CWs with different walnut peel amendment proportions (0%, 25%, 50%, 75%) were developed to explore the effects of biomass dosage on the treatment performance, nitrous oxide (N2O) emission and microbial metabolites. Results showed that the addition of biomass significantly enhanced the denitrification performance in all CWs, and the higher total nitrogen (TN) removal efficiency (91.14-97.16%) was achieved in CWs with the optimal dosage of 25%. While the addition of biomass resulted in a slight increase in N2O emission (20.56-270.13 μg m-2 h-1) compared with control systems. Additionally, the biomass addition increased the accumulation of extracellular polymeric substances (EPS) by facilitating microbial processes. Higher total EPS production was observed in CW with 25% biomass, and the proportion of tightly bound EPS (48%) dominated in the total EPS in different CWs.
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Affiliation(s)
- Yingrun Chen
- College of Environmental Science & Engineering, Shandong University, Qingdao, 266237, PR China; College of Resources and Environment, Northwest A&F University, Yangling, Shaanxi, 712100, PR China
| | - Jian Zhang
- College of Environmental Science & Engineering, Shandong University, Qingdao, 266237, PR China
| | - Zizhang Guo
- College of Environmental Science & Engineering, Shandong University, Qingdao, 266237, PR China
| | - Ming Li
- College of Resources and Environment, Northwest A&F University, Yangling, Shaanxi, 712100, PR China
| | - Haiming Wu
- College of Environmental Science & Engineering, Shandong University, Qingdao, 266237, PR China.
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16
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Lu J, Guo Z, Pan Y, Li M, Chen X, He M, Wu H, Zhang J. Simultaneously enhanced removal of PAHs and nitrogen driven by Fe 2+/Fe 3+ cycle in constructed wetland through automatic tidal operation. WATER RESEARCH 2022; 215:118232. [PMID: 35247604 DOI: 10.1016/j.watres.2022.118232] [Citation(s) in RCA: 39] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 02/14/2022] [Accepted: 02/24/2022] [Indexed: 06/14/2023]
Abstract
The lack of dissolved oxygen and weak substrate removal capacity in constructed wetlands (CW) leads to terrible removal of nitrogen and polycyclic aromatic hydrocarbons (PAHs). In this study, automatic tidal flow CW microcosms were constructed by improving the oxygen environment (siphon and air-duct) and substrate (magnetite) to enhance purification performance and the mechanism was explored. The results showed that the addition of air-duct could improve the oxygen collection and thus improved the NH4+ removal efficiency. Additionally, nitrogen removal was improved greatly due to the simultaneous nitrification and denitrification in aerobic layer with the addition of magnetite. Mass balance indicated the microbial degradation dominated (32-62%) the removal of PAHs. Metagenomic analysis proved the existence of magnetite enhanced the number of PAHs-degrading bacteria, functional groups and metabolic pathways and thus greatly improved the microbial degradation of PAHs. Furthermore, Fe2+/Fe3+ cycle played an important role in promoting the anaerobic degradation of PAHs, which might be served as an electron conduit to establish the direct interspecies electron transfer between iron-reducing bacteria (e.g. Deltaproteobacteria bacterium) and Anaerolineae bacterium to degrade PAHs efficiently. This study provided better understanding of the simultaneous removal of PAHs and nitrogen in tidal flow CWs.
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Affiliation(s)
- Jiaxing Lu
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China
| | - Zizhang Guo
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China.
| | - Yitong Pan
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China
| | - Mengting Li
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China
| | - Xinhan Chen
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China
| | - Mingyu He
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China
| | - Haiming Wu
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China
| | - Jian Zhang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China; College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao 266590, China.
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17
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Li M, Zhang J, Liang S, Li M, Wu H. Novel magnetic coupling constructed wetland for nitrogen removal: Enhancing performance and responses of plants and microbial communities. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 819:152040. [PMID: 34856252 DOI: 10.1016/j.scitotenv.2021.152040] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 11/23/2021] [Accepted: 11/24/2021] [Indexed: 06/13/2023]
Abstract
Vertical flow constructed wetlands (VFCWs) have been widely applied worldwide due to their small footprint and large hydraulic load, however, its sustainable operation and application is still challenging because of the unsatisfactory nitrogen removal. This study developed a novel CW coupled with a magnetic field for treating simulated wastewater, and investigated the effects of magnetic field on enhancing treatment performance and responses of wetland plants and microbial community. The results showed that the magnetic field (average 110 mT) had a significantly intensifying effect on organics and nitrogen removal. The removal efficiencies of NH4+-N and TN in CW exposed to magnetic field (MF-CW) were 10.14% and 9.16% higher than those in control CW (C-CW), and an increased COD removal was also found in MF-CW. Biochemical characteristics of plants indicated that the MF did not cause a severe stress for wetland plants, while MF application shifted significantly the microbial community in CWs. Relative abundances of nitrifying bacteria such as Nitrospira (2.36%), Dokdonella (0.27%) and Nitrosomonas (0.17%) had been significantly promoted due to MF exposure, and nitrification-related microbial enzyme (AMO) activity was also increased by 63%. It can be concluded that introducing MF into CWs could intensify organics and nitrogen removal via the biological process, which would contribute to a better understanding of magnetic coupling mechanism.
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Affiliation(s)
- Mengqi Li
- College of Environmental Science & Engineering, Shandong University, Qingdao 266237, PR China; College of Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, PR China
| | - Jian Zhang
- College of Environmental Science & Engineering, Shandong University, Qingdao 266237, PR China
| | - Shuang Liang
- College of Environmental Science & Engineering, Shandong University, Qingdao 266237, PR China
| | - Ming Li
- College of Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, PR China
| | - Haiming Wu
- College of Environmental Science & Engineering, Shandong University, Qingdao 266237, PR China.
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18
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Seasonal Enhancement of Nitrogen Removal on Domestic Wastewater Treatment Performance by Partially Saturated and Saturated Hybrid Constructed Wetland. WATER 2022. [DOI: 10.3390/w14071089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The aim of this study is to evaluate seasonal enhancement of nitrogen removal on domestic wastewater treatment performance by partially saturated and saturated HBCWs. To achieve this, two HBCWs consisting of a vertical subsurface flow constructed wetland, followed by a horizontal subsurface flow constructed wetland (VSSF-HSSF) were evaluated. Two saturation levels were used: (a) partially saturated HB1:VSSF1 (0.6 m)-HSSF1 (0.15 m), (b) saturated HB2: VSSF2 (0.8 m)-HSSF2 (0.25 m). Each unit was planted with Schoenoplectus californicus and was operated for 297 days. The removal efficiencies in HB1 and HB2 were above 70%, 86%, 77% and 55% for chemical oxygen demand (COD), total suspended solids (TSS), nitrogen as ammonium (NH4+-N), and total nitrogen (TN), respectively. For VSSF, a higher level of saturation (from 0.6 to 0.8 m) meant a decrease of 17% in the TN removal efficiencies, and for HSSF, an increase from 0.15 to 0.25 m of saturation meant a decrease of 11 and 10% in the NH4+-N and TN removal efficiencies, respectively. Thus, the increase of saturation level in HBCWs reduces the transformation and/or removal of components of the wastewaters to be treated, particularly nitrogen. Through this research, the possibility of optimizing the transformation of nitrogen with partially saturated hybrids can be examined.
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19
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Weng R, He Y, Wang J, Zhang Z, Wei Z, Yang Y, Huang M, Zhou G. Quantitative characterization and genetic diversity associated with N-cycle pathways in urban rivers with different remediation techniques. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 804:150235. [PMID: 34798749 DOI: 10.1016/j.scitotenv.2021.150235] [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: 08/13/2021] [Revised: 09/04/2021] [Accepted: 09/05/2021] [Indexed: 06/13/2023]
Abstract
The nitrate reduction contributions of denitrification, anaerobic ammonium oxidation (anammox) and dissimilatory nitrate reduction to ammonium (DNRA) remain largely unknown especially in the context of river remediation. In this research, the quantitative differentiation of these three nitrate-reduction processes with different remediation conditions was done by the joint use of microbial analysis and nitrogen isotope-tracing. The experiments were done in simulated river systems with 100-day operations. The results of isotope-tracing showed that the respective N-removal contribution of denitrification was 85.88%-92.46% and 83.49%-84.73% in urban river with aeration and addition of Ca(NO3)2, whereas anammox became the same important (contribution of 49.35%-57.85%) with denitrification for nitrogen removal at a high C/N (Chemical oxygen demand/total nitrogen) ratio of 20. Besides, DNRA only occurred at a C/N ratio of 10 with high-level ammonium accumulation (11.20 ± 0.61 mg/L). Microbial analyses indicated that Ca(NO3)2 injection could promote not only the relative abundance of Proteobacteria (from 47.66% to 59.52%) but also the abundance of hzsB (from (4.66 ± 0.40) × 104 copies·g-1 to (2.66 ± 0.12) × 105 copies·g-1). Moreover, Ca(NO3)2 injection showed significantly positive correlation with Candidatus Jettenia of hzsB and Thiobacillus of all the denitrification functional genes including narG, norB, nosZ and nirS. The C/N ratio showed significantly positive correlation with Azoarcus of nirS (r = 0.941, p < 0.01) and Alloactinosynnema of hzsB (r = 0.941, p < 0.01). It was worth noting that Thiobacillus dominated in N-transformation processes, which underlined the need for the coupling of N transformation with other elements such as sulfur for better understanding and manipulating N cycling in urban rivers.
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Affiliation(s)
- Rui Weng
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, Institute of Eco-Chongming, Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area, Ministry of Natural Resources, Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, East China Normal University, Shanghai 200241, China.
| | - Yan He
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, Institute of Eco-Chongming, Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area, Ministry of Natural Resources, Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, East China Normal University, Shanghai 200241, China.
| | - Jianhua Wang
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, Institute of Eco-Chongming, Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area, Ministry of Natural Resources, Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, East China Normal University, Shanghai 200241, China.
| | - Zhen Zhang
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, Institute of Eco-Chongming, Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area, Ministry of Natural Resources, Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, East China Normal University, Shanghai 200241, China.
| | - Zheng Wei
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, Institute of Eco-Chongming, Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area, Ministry of Natural Resources, Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, East China Normal University, Shanghai 200241, China.
| | - Yanmei Yang
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, Institute of Eco-Chongming, Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area, Ministry of Natural Resources, Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, East China Normal University, Shanghai 200241, China.
| | - Minsheng Huang
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, Institute of Eco-Chongming, Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area, Ministry of Natural Resources, Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, East China Normal University, Shanghai 200241, China.
| | - Gongming Zhou
- The State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, China.
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20
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Wang L, Xu D, Zhang Q, Liu T, Tao Z. Simultaneous removal of heavy metals and bioelectricity generation in microbial fuel cell coupled with constructed wetland: an optimization study on substrate and plant types. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:768-778. [PMID: 34341922 DOI: 10.1007/s11356-021-15688-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 07/23/2021] [Indexed: 06/13/2023]
Abstract
A microbial fuel cell coupled with constructed wetland (CW-MFC) was built to remove heavy metals (Zn and Ni) from sludge. The performance for the effects of substrates (granular activated carbon (GAC), ceramsite) and plants (Iris pseudacorus, water hyacinth) towards the heavy metal treatment as well as electricity generation was systematically investigated to determine the optimal constructions of CW-MFCs. The CW-MFC systems possessed higher Zn and Ni removal efficiencies as compared to CW. The maximal removal rates of Zn (76.88%) and Ni (66.02%) were obtained in system CW-MFC based on GAC and water hyacinth (GAC- and WH-CW-MFC). Correspondingly, the system produced the maximum voltage of 534.30 mV and power density of 70.86 mW·m-3, respectively. Plant roots and electrodes contributed supremely to the removal of heavy metals, especially for GAC- and WH-CW-MFC systems. The coincident enrichment rates of Zn and Ni reached 21.10% and 26.04% for plant roots and 14.48% and 16.50% for electrodes, respectively. A majority of the heavy metals on the sludge surface were confirmed as Zn and Ni. Furthermore, the high-valence Zn and Ni were effectively reduced to low-valence or elemental metals. This study provides a theoretical guidance for the optimal construction of CW-MFC and the resource utilization of sludge containing heavy metals.
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Affiliation(s)
- Lu Wang
- School of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, 241000, Anhui, China
| | - Dayong Xu
- School of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, 241000, Anhui, China
| | - Qingyun Zhang
- School of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, 241000, Anhui, China.
| | - Tingting Liu
- School of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, 241000, Anhui, China
| | - Zhengkai Tao
- School of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, 241000, Anhui, China
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21
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Nguyen XC, Nguyen TTH, Le QV, Le PC, Srivastav AL, Pham QB, Nguyen PM, La DD, Rene ER, Ngo HH, Chang SW, Nguyen DD. Developing a new approach for design support of subsurface constructed wetland using machine learning algorithms. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 301:113868. [PMID: 34628282 DOI: 10.1016/j.jenvman.2021.113868] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 09/07/2021] [Accepted: 09/26/2021] [Indexed: 06/13/2023]
Abstract
Knowing the effluent quality of treatment systems in advance to enable the design of treatment systems that comply with environmental standards is a realistic strategy. This study aims to develop machine learning - based predictive models for designing the subsurface constructed wetlands (SCW). Data from the SCW literature during the period of 2009-2020 included 618 sets and 10 features. Five algorithms namely, Random forest, Classification and Regression trees, Support vector machines, K-nearest neighbors, and Cubist were compared to determine an optimal algorithm. All nine input features including the influent concentrations, C:N ratio, hydraulic loading rate, height, aeration, flow type, feeding, and filter type were confirmed as relevant features for the predictive algorithms. The comparative result revealed that Cubist is the best algorithm with the lowest RMSE (7.77 and 21.77 mg.L-1 for NH4-N and COD, respectively) corresponding to 84% of the variance in the effluents explained. The coefficient of determination of the Cubist algorithm obtained for NH4-N and COD prediction from the test data were 0.92 and 0.93, respectively. Five case studies of the application of SCW design were also exercised and verified by the prediction model. Finally, a fully developed Cubist algorithm-based design tool for SCW was proposed.
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Affiliation(s)
- Xuan Cuong Nguyen
- Laboratory of Energy and Environmental Science, Institute of Research and Development, Duy Tan University, Da Nang, 550000, Viet Nam; Faculty of Environmental Chemical Engineering, Duy Tan University, Da Nang, 550000, Viet Nam
| | - Thi Thanh Huyen Nguyen
- Laboratory of Energy and Environmental Science, Institute of Research and Development, Duy Tan University, Da Nang, 550000, Viet Nam; Faculty of Environmental Chemical Engineering, Duy Tan University, Da Nang, 550000, Viet Nam
| | - Quyet V Le
- Department of Materials Science and Engineering, Institute of Green Manufacturing Technology, Korea University, Seoul 02841, Republic of Korea
| | - Phuoc Cuong Le
- Department of Environmental Management, Faculty of Environment, The University of Danang-University of Science and Technology, Danang, 550000, Viet Nam
| | - Arun Lal Srivastav
- Chitkara University School of Engineering and Technology, Chitkara University, Himachal Pradesh, India
| | - Quoc Bao Pham
- Institute of Applied Technology, Thu Dau Mot University, Binh Duong Province, Viet Nam
| | - Phuong Minh Nguyen
- Faculty of Environmental Sciences, University of Science, Vietnam National University, 334 Nguyen Trai, Thanh Xuan, Hanoi, Viet Nam
| | - D Duong La
- Institute of Chemistry and Materials, Nghia Do, Cau Giay, Hanoi, Viet Nam
| | - Eldon R Rene
- Department of Environmental Engineering and Water Technology, IHE Delft Institute for Water Education, 2601DA Delft, the Netherlands
| | - H Hao Ngo
- Center for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Australia
| | - S Woong Chang
- Department of Environmental Energy Engineering, Kyonggi University, Suwon 442-760, Republic of Korea
| | - D Duc Nguyen
- Faculty of Environmental and Food Engineering, Nguyen Tat Thanh University, 300A Nguyen Tat Thanh, District 4, Ho Chi Minh City, 755414, Viet Nam; Department of Environmental Energy Engineering, Kyonggi University, Suwon 442-760, Republic of Korea.
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22
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Wang Y, Wang WH, Zhang H, Yan FL, Li JJ. Treatment of the actual landfill leachate in different constructed wetlands through intermittent and varied aeration mode. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:64858-64870. [PMID: 34322817 DOI: 10.1007/s11356-021-15216-3] [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: 03/03/2021] [Accepted: 06/27/2021] [Indexed: 06/13/2023]
Abstract
This study focused on the removal of organic matter and nitrogen and explored the feasible operation strategies to achieve short-cut nitrification and denitrification in two constructed wetlands (CWs), which were designed to treat the actual landfill leachate from a small county in parallel. The two CWs were horizontal sub-surface flow constructed wetlands (HFCW) with partial-area aeration and vertical sub-surface flow constructed wetlands (VFCW) with full-area aeration. The experimental results showed that both CWs could achieve an excellent organic matter and nitrogen removal performance under the conditions of intermittent aeration with high frequency and medium intensity (2 h of aeration and 4 h of rest). The removal efficiencies of COD and total nitrogen by HFCW were 89.08% and 73.22%, and the corresponding values of VFCW were 84.51% and 71.44%, respectively. Meanwhile, the inhibition kinetics model indicated that HFCW with partial-area aeration could enhance the free ammonium (FA) tolerance of ammonium-oxidizing bacteria (AOB) and reduce the conversion percentage of ammonia nitrogen. In addition, the intermittent aeration mode with high frequency and medium intensity could keep the DO concentration below under 0.60 mg L-1 in HFCW, which helped to achieve stable short-cut nitrification and ensure the average nitrite accumulation rate (NAR) reach 50.96%. These results suggested that the intermittent aeration in partial-area could achieve successful short-cut nitrification in HFCW, thereby improving the removal efficiency of nitrogen in landfill leachate.
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Affiliation(s)
- Yi Wang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, No. 13 Yanta Road, Beilin District, Xi'an, Shaanxi, China.
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, People's Republic of China.
| | - Wen-Huai Wang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, No. 13 Yanta Road, Beilin District, Xi'an, Shaanxi, China
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, People's Republic of China
| | - Heng Zhang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, No. 13 Yanta Road, Beilin District, Xi'an, Shaanxi, China
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, People's Republic of China
| | - Fei-Long Yan
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, No. 13 Yanta Road, Beilin District, Xi'an, Shaanxi, China
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, People's Republic of China
| | - Jia-Jun Li
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, No. 13 Yanta Road, Beilin District, Xi'an, Shaanxi, China
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, People's Republic of China
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Chi Z, Hou L, Li H. Effects of pollution load and salinity shock on nitrogen removal and bacterial community in two-stage vertical flow constructed wetlands. BIORESOURCE TECHNOLOGY 2021; 342:126031. [PMID: 34582988 DOI: 10.1016/j.biortech.2021.126031] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 09/20/2021] [Accepted: 09/23/2021] [Indexed: 06/13/2023]
Abstract
To understand the denitrification performance and microbial community of two-stage vertical flow constructed wetlands (TS-VFCWs) with iron ore/manganese ore and wood chips, COD and nitrogen removal were investigated under pollution load and salinity shock. High removal of COD (87%), NH4+-N (97%), and NO3--N (98%) were achieved with increasing load, but the high pollutant load inhibited the denitrification performance in TS-VFCW with iron ore and wood chips. TS-VFCW with iron ore and wood chips showed good recovery potential with decreasing load. High NH4+-N removal was observed in TS-VFCW with manganese ore and wood chips. Treatment with 3% salinity decreased COD and NH4+-N removal but improved NO3--N removal, maintaining relatively good nitrogen removal. The addition of iron ore and manganese ore enriched nitrifying bacteria Flavobacterium and autotrophic denitrifying bacteria, while wood chips promoted heterotrophic denitrification and organic degradation. In addition, ubiquitous denitrifying bacteria under salinity ensured excellent denitrification performance.
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Affiliation(s)
- Zifang Chi
- Key Lab of Groundwater Resources and Environment, Ministry of Education, Jilin University, Changchun 130021, PR China
| | - Lining Hou
- Key Lab of Groundwater Resources and Environment, Ministry of Education, Jilin University, Changchun 130021, PR China
| | - Huai Li
- Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, PR China.
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Wang X, Bai J, Tian Y, Wang T, Zhou X, Zhang C. Synergistic effects of natural ventilation and animal disturbance on oxygen transfer, pollutants removal and microbial activity in constructed wetlands. CHEMOSPHERE 2021; 283:131175. [PMID: 34157618 DOI: 10.1016/j.chemosphere.2021.131175] [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: 02/03/2021] [Revised: 05/11/2021] [Accepted: 06/05/2021] [Indexed: 06/13/2023]
Abstract
This study investigated the feasibility of combining natural ventilation and animal disturbance in constructed wetlands (CWs) and the joint effects on oxygen transfer, microbial activity, organics, and nitrogen removal. The results showed that natural ventilation extended the habitat depth of earthworms by approximately 10 cm by significantly improving oxygen transfer in CWs; in turn, the earthworms slightly promoted the addition of oxygen inside CWs through burrowing activity. Therefore, the interaction between natural ventilation and animal disturbance in CWs mutually reinforced oxygen transfer, enzymatic activity, and the ammonification, nitrification, and aerobic degradation of organics. Additionally, the combination of natural ventilation and animal disturbance in CWs promoted the oxygen transfer rate by 42.1%-68.2%; promoted catalase, urease, and dehydrogenase activity by 19.3%-24.8%, 17.4%-22.3%, and 18.1%-25.6%, respectively; and promoted COD and NH3-N removal loads by 48.6%-74.2% and 94.9%-135.3%, respectively. To achieve higher total nitrogen removal, moderate wind speeds (≤1 m/s in this study) are recommended to simultaneously create aerobic and anoxic/anaerobic conditions. Although natural ventilation reduced the microbial diversity in CWs by promoting the abundance of aerobes, the combination of natural ventilation and animal disturbance was generally conducive to improving microbial diversity. The relationship between wind speed and oxygen transfer rate and COD and NH3-N removal loads in naturally ventilated CWs conformed to cubic equations.
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Affiliation(s)
- Xiaoou Wang
- Key Laboratory of Clean Energy Utilization and Pollutant Control in Tianjin, School of Energy and Environmental Engineering, Hebei University of Technology, China
| | - Jun Bai
- Key Laboratory of Clean Energy Utilization and Pollutant Control in Tianjin, School of Energy and Environmental Engineering, Hebei University of Technology, China
| | - Yimei Tian
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300350, China
| | - Tao Wang
- Key Laboratory of Clean Energy Utilization and Pollutant Control in Tianjin, School of Energy and Environmental Engineering, Hebei University of Technology, China
| | - Xiaoxuan Zhou
- Key Laboratory of Clean Energy Utilization and Pollutant Control in Tianjin, School of Energy and Environmental Engineering, Hebei University of Technology, China
| | - Changping Zhang
- Key Laboratory of Clean Energy Utilization and Pollutant Control in Tianjin, School of Energy and Environmental Engineering, Hebei University of Technology, China.
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25
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Yan FL, Wang Y, Wang WH, Zhang H, Zheng YC, Kou XM, Wu SZ, Shao T. Effect of first-stage aeration on treatment of domestic sewage in different hybrid constructed wetlands. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:43402-43416. [PMID: 33834330 DOI: 10.1007/s11356-021-12449-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 01/08/2021] [Indexed: 06/12/2023]
Abstract
Two sets of hybrid constructed wetlands (HCWs) with the first-stage aeration were used to treat actual domestic sewage in this paper, where the effects of three important factors of aeration mode, hydraulic loading rates (HLR), and aeration volume on the removal of pollutants in both HCWs were studied in contrasts. In addition, the pollutant removal efficiency, the contribution of plants, and the characteristics of biofilm in both HCWs were explored. The results of 250-day experiment showed that the TN removal capacity of HCW combining vertical flow CW with horizontal flow CW (VF-HF) was better than HCW's converse combination (HF-VF) in treatingsewage, while the removal efficiency of COD and NH4+-N were similar, and the concentrations of TN and COD in the effluent of VF-HF could successfully meet the National discharge requirements. Compared with the continuous aeration, the intermittent aeration only had a little effect on the removal of COD and NH4+-N, but could improve TN removal performance in both HCWs. Meanwhile, increasing the aeration volume was beneficial to remove NH4+-N but not TN in HCWs. In addition, although the pollutant removal performances in both HCWs were impacted, the removal capacity of TN in VF-HF was only affected a little, when HLR was increased by 50%. The contribution of plants' uptake accounted for about 10% to nitrogen removal and 20% to phosphorus removal in both HCWs. The biomass at the filler surface near the plant rhizosphere was greater than that in the non-rhizosphere zones, and the impact of plant rhizosphere on the nitrification activity of biofilm was significantly greater than that on denitrification activity in both HCWs.
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Affiliation(s)
- Fei-Long Yan
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, China
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, People's Republic of China
| | - Yi Wang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, China.
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, People's Republic of China.
| | - Wen-Huai Wang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, China
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, People's Republic of China
| | - Heng Zhang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, China
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, People's Republic of China
| | - Yu-Cong Zheng
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, China
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, People's Republic of China
| | - Xiao-Mei Kou
- Power China-Northwest Engineering Corporation Limited, Xi'an, 710065, China
| | - Shi-Zhang Wu
- Power China-Northwest Engineering Corporation Limited, Xi'an, 710065, China
| | - Tian Shao
- Power China-Northwest Engineering Corporation Limited, Xi'an, 710065, China
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26
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Zhou S, Xu S, Jiang Y, Jiang C, Wang D, Xu G, Yang D, Wu S, Bai Z, Zhuang G, Zhuang X. Enhancing nitrogen removal from anaerobically-digested swine wastewater through integration of Myriophyllum aquaticum and free nitrous acid-based technology in a constructed wetland. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 779:146441. [PMID: 34030237 DOI: 10.1016/j.scitotenv.2021.146441] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 02/20/2021] [Accepted: 03/07/2021] [Indexed: 06/12/2023]
Abstract
Despite of low operation costs and convenient maintenance, the application of natural systems for swine wastewater treatment has been limited by large construction area and unsatisfactory effluent quality. Introducing ammonium high uptake aquatic plants and shifting nitrogen removal pathway from nitrate to nitrite in constructed wetlands (CWs) has been regarded as promising approach to promote their performances. This study aimed to establish nitrite pathway and enhance N removal via free nitrous acid (FNA)-sediment treatment and Myriophyllum aquaticum vegetation in the CWs treating anaerobically digested swine wastewater. Nitrite pathway was successfully and stably achieved in the M. aquaticum CW with FNA-treated sediment. The overall removal efficiencies of ammonium nitrogen and total nitrogen were 42.3 ± 10.2% and 37.7 ± 9.3% in the planted CWs with FNA-treated sediment, which were 76.3% and 65.4% higher than those in the conventional oxidation pond system, respectively. Microbial community analysis (qPCR and metagenomics) suggested that the nitrite pathway established through FNA-sediment treatment was based on the inactivation of nitrite oxidizing bacteria (lower nxrA gene abundance) and the reduction of relative abundances of NOB (especially Nitrobacter and Nitrospira). During the denitrification processes, the integration of M. aquaticum vegetation with FNA-sediment treatment can lower the nitrate reduction by decreasing narG gene abundances and decreasing the relative abundances of napA affiliated bacteria (especially Bradyrhizobium), while strengthening reduction of nitrite and nitrous oxide by increasing nirK and nosZ gene abundances and enriching the corresponding affiliated microbial taxa, Mycobacterium and Bacillus, respectively. Our findings suggest that applying FNA-based technology in CW systems is technically and economically feasible, which holds promise for upgrading current CW systems treating swine wastewater to meet future water quality requirements.
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Affiliation(s)
- Sining Zhou
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Sino-Danish Center, University of Chinese Academy of Sciences, Beijing 101408, China
| | - Shengjun Xu
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Yangtze River Delta Branch, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Yiwu 322000, China
| | - Yishuai Jiang
- School of Civil and Environmental Engineering, Nanyang Technological University, 639798, Singapore
| | - Cancan Jiang
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Danhua Wang
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Guanglian Xu
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Dongmin Yang
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Shanghua Wu
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Zhihui Bai
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Sino-Danish Center, University of Chinese Academy of Sciences, Beijing 101408, China
| | - Guoqiang Zhuang
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Sino-Danish Center, University of Chinese Academy of Sciences, Beijing 101408, China
| | - Xuliang Zhuang
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Sino-Danish Center, University of Chinese Academy of Sciences, Beijing 101408, China.
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Ávila C, García-Galán MJ, Uggetti E, Montemurro N, García-Vara M, Pérez S, García J, Postigo C. Boosting pharmaceutical removal through aeration in constructed wetlands. JOURNAL OF HAZARDOUS MATERIALS 2021; 412:125231. [PMID: 33550125 DOI: 10.1016/j.jhazmat.2021.125231] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Revised: 01/11/2021] [Accepted: 01/22/2021] [Indexed: 06/12/2023]
Abstract
This work evaluated the removal efficiency of 13 wastewater-borne pharmaceuticals in a pilot constructed wetland (CW) operated under different aeration strategies (no aeration, intermittent and continuous). Aeration improved the removal of conventional wastewater parameters and the targeted micropollutants, compared to the non-aerated treatment. Reduction of chemical oxygen demand (COD) and total nitrogen (TN) was slightly higher applying intermittent aeration than applying continuous aeration, the opposite was observed for the investigated pharmaceuticals. Seven targeted compounds were found in influent wastewater, and five of them (acetaminophen, diclofenac, ketoprofen, bezafibrate and gemfibrozil) were efficiently removed (> 83%) in the aerated systems. The overall risk of the investigated samples against aquatic ecosystems was moderate, decreasing in the order influent > no aeration > intermittent aeration > continuous aeration, based on the hazard quotient approach. Lorazepam, diclofenac and ketoprofen were the pharmaceuticals that could contribute the most to this potential environmental impact of the CW effluents after discharge. To the authors' knowledge this is the first sound study on the removal and fate of ketoprofen, bezafibrate, and lorazepam in aerated CWs, and provides additional evidence on the removal and fate of acetaminophen, diclofenac, gemfibrozil, and carbamazepine in this type of bioremediation systems at pilot plant scale.
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Affiliation(s)
- Cristina Ávila
- AIMEN Technology Center, c/ Relva, 27A - Torneiros, Pontevedra, 36410 Porriño, Spain; ICRA, Catalan Institute for Water Research, Scientific and Technological Park of the University of Girona, Emili Grahit, 101, E-17003 Girona, Spain; Universitat de Girona, E-17003 Girona, Spain
| | - María Jesús García-Galán
- GEMMA-Group of Environmental Engineering and Microbiology, Department of Civil and Environmental Engineering, Universitat Politècnica de Catalunya-BarcelonaTech, c/ Jordi Girona 1-3, Building D1, E-08034 Barcelona, Spain
| | - Enrica Uggetti
- GEMMA-Group of Environmental Engineering and Microbiology, Department of Civil and Environmental Engineering, Universitat Politècnica de Catalunya-BarcelonaTech, c/ Jordi Girona 1-3, Building D1, E-08034 Barcelona, Spain.
| | - Nicola Montemurro
- Water, Environmental and Food Chemistry Unit (ENFOCHEM), Department of Environmental Chemistry, Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Jordi Girona 18, Barcelona 08034, Spain
| | - Manuel García-Vara
- Water, Environmental and Food Chemistry Unit (ENFOCHEM), Department of Environmental Chemistry, Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Jordi Girona 18, Barcelona 08034, Spain
| | - Sandra Pérez
- Water, Environmental and Food Chemistry Unit (ENFOCHEM), Department of Environmental Chemistry, Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Jordi Girona 18, Barcelona 08034, Spain
| | - Joan García
- GEMMA-Group of Environmental Engineering and Microbiology, Department of Civil and Environmental Engineering, Universitat Politècnica de Catalunya-BarcelonaTech, c/ Jordi Girona 1-3, Building D1, E-08034 Barcelona, Spain
| | - Cristina Postigo
- Water, Environmental and Food Chemistry Unit (ENFOCHEM), Department of Environmental Chemistry, Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Jordi Girona 18, Barcelona 08034, Spain
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Li J, Zheng L, Ye C, Ni B, Wang X, Liu H. Evaluation of an intermittent-aeration constructed wetland for removing residual organics and nutrients from secondary effluent: Performance and microbial analysis. BIORESOURCE TECHNOLOGY 2021; 329:124897. [PMID: 33657501 DOI: 10.1016/j.biortech.2021.124897] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 02/18/2021] [Accepted: 02/20/2021] [Indexed: 05/16/2023]
Abstract
This study proposed a novel intermittent-aeration constructed wetland (CW) to resolve the vertical loss of oxygen in tertiary treatment. Compared to the non-aeration CW, the intermittent-aeration CW presented a better removal performance (90.8% chemical oxygen demand, 94.3% ammonia nitrogen, 91.5% total nitrogen and 94.1% total phosphorus) at a dissolved oxygen of 3 mg L-1 and hydraulic retention time of 2 days. It was mainly attributed to the higher abundance and greater diversity of bacterial community due to the oxygen supply. High-throughput sequencing indicated that high abundance of phyla Proteobacteria (35.34%) and Bacteroidetes (18.20%) in intermittent-aeration CW were responsible for simultaneous nitrogen and phosphorus removal. Besides, the dominant families Burkholderiaceae (11.16%), Microtrichales (6.88%) and Saprospiraceae (6.50%) were also detected, which was vital to hydrolyze and utilize complex organic matters. In general, oxygen supply upregulated the metabolism pathways of amino acid and carbohydrate, bringing a greater biodegradation potential for removing contaminants.
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Affiliation(s)
- Jia Li
- Key Laboratory of Hydraulic and Waterway Engineering of the Ministry of Education, School of River and Ocean Engineering, Chongqing Jiaotong University, Chongqing 400074, PR China; Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, PR China; Research Center for Pollution Control and Ecological Restoration, Yuxi Normal University, Yuxi 653100, Yunnan, PR China
| | - Lei Zheng
- Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, PR China; Centre for Technology in Water and Wastewater, University of Technology Sydney, Ultimo, NSW 2007, Australia
| | - Changbing Ye
- Research Center for Pollution Control and Ecological Restoration, Yuxi Normal University, Yuxi 653100, Yunnan, PR China
| | - Baosen Ni
- Research Center for Pollution Control and Ecological Restoration, Yuxi Normal University, Yuxi 653100, Yunnan, PR China
| | - Xingzhu Wang
- Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, PR China
| | - Hong Liu
- Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, PR China.
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He Y, Zhang L, Jiang L, Wagner T, Sutton NB, Ji R, Langenhoff AAM. Improving removal of antibiotics in constructed wetland treatment systems based on key design and operational parameters: A review. JOURNAL OF HAZARDOUS MATERIALS 2021; 407:124386. [PMID: 33144002 DOI: 10.1016/j.jhazmat.2020.124386] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 10/03/2020] [Accepted: 10/23/2020] [Indexed: 05/12/2023]
Abstract
While removal of antibiotics in constructed wetland treatment systems (CWTS) has been described previously, few studies examined the synergistic effect of multiple design and operational parameters for improving antibiotic removal. This review describes the removal of 35 widely used antibiotics in CWTS covering the most common design parameters (flow configuration, substrate, plants) and operational parameters (hydraulic retention time/hydraulic loading rates, feeding mode, aeration, influent quality), and discusses how to tailor those parameters for improving antibiotic removal based on complex removal mechanisms. To achieve an overall efficient removal of antibiotics in CWTS, our principal component analysis indicated that optimization of flow configuration, selection of plant species, and compensation for low microbial activity at low temperature is the priority strategy. For instance, a hybrid-CWTS that integrates the advantages of horizontal and vertical subsurface flow CWTS may provide a sufficient removal performance at reasonable cost and footprint. To target removal of specific antibiotics, future research should focus on elucidating key mechanisms for their removal to guide optimization of the design and operational parameters. More efficient experimental designs (e.g., the Box-Behnken design) are recommended to determine the settings of the key parameters. These improvements would promote development of this environmentally friendly and cost-efficient technology for antibiotic removal.
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Affiliation(s)
- Yujie He
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Xianlin Avenue 163, 210023 Nanjing, China; Quanzhou Institute for Environment Protection Industry, Nanjing University, Beifeng Road, 362000 Quanzhou China
| | - Li Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Xianlin Avenue 163, 210023 Nanjing, China; Quanzhou Institute for Environment Protection Industry, Nanjing University, Beifeng Road, 362000 Quanzhou China
| | - Longxue Jiang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Xianlin Avenue 163, 210023 Nanjing, China
| | - Thomas Wagner
- Department of Environmental Technology, Wageningen University and Research, P.O. Box 17, 6700 AA Wageningen, The Netherlands
| | - Nora B Sutton
- Department of Environmental Technology, Wageningen University and Research, P.O. Box 17, 6700 AA Wageningen, The Netherlands
| | - Rong Ji
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Xianlin Avenue 163, 210023 Nanjing, China; Quanzhou Institute for Environment Protection Industry, Nanjing University, Beifeng Road, 362000 Quanzhou China.
| | - Alette A M Langenhoff
- Department of Environmental Technology, Wageningen University and Research, P.O. Box 17, 6700 AA Wageningen, The Netherlands
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He Y, Zhou Y, Weng R, Wang J, Chen J, Huang M. Responses of Ammonia-Oxidizing Archaea and Bacteria in Malodorous River Sediments to Different Remediation Techniques. MICROBIAL ECOLOGY 2021; 81:314-322. [PMID: 32935184 DOI: 10.1007/s00248-020-01597-4] [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: 05/31/2020] [Accepted: 09/01/2020] [Indexed: 06/11/2023]
Abstract
In this study, the joint use of high throughput sequencing, real-time quantitative PCR, and ammonia-oxidizing bacteria (AOB)-inhibiting allylthiourea was used to differentiate between the contributions of ammonia-oxidizing archaea (AOA) vs AOB to ammonia oxidation and ascertain how AOA and AOB responded to two widely used river remediation techniques (aeration and Ca(NO3)2 injection). Results showed that ammonia oxidation was largely attributed to ATU-sensitive AOB rather than AOA and Nitrosomonas was the predominant AOB-related genus (53.86%) in the malodorous river. The contribution of AOB to ammonia oxidation in the context of aeration and Ca(NO3)2 injection was 75.51 ± 2.77% and 60.19 ± 10.44%, respectively. The peak of AOB/AOA ratio and the marked increase of relative abundances of Nitrosomonas and Nitrosospira in aeration runs further demonstrated aeration favored the ammonia oxidation of AOB. Comparatively, Ca(NO3)2 injection could increase the ammonia oxidation contribution of AOA from 31.32 ± 6.06 to 39.81 ± 10.44% and was significantly correlated with Nitrosococcus of AOB (r = 0.796, p < 0.05), Candidatus_Nitrosopelagicus of AOA (r = 0.986, p < 0.01), and AOA Simpson diversity (r = - 0.791, p < 0.05). Moreover, Candidatus_Nitrosopelagicus was only present in Ca(NO3)2 runs. Taken together, Ca(NO3)2 was recognized as an important factor in mediating the growth and ecological niches of ammonia oxidizers.Graphical abstract.
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Affiliation(s)
- Yan He
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, Institute of Eco-Chongming, Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area, Ministry of Natural Resources, East China Normal University, Shanghai, 200241, China.
| | - Yunchang Zhou
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, Institute of Eco-Chongming, Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area, Ministry of Natural Resources, East China Normal University, Shanghai, 200241, China
| | - Rui Weng
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, Institute of Eco-Chongming, Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area, Ministry of Natural Resources, East China Normal University, Shanghai, 200241, China
| | - Jianhua Wang
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, Institute of Eco-Chongming, Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area, Ministry of Natural Resources, East China Normal University, Shanghai, 200241, China
| | - Jinghan Chen
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, Institute of Eco-Chongming, Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area, Ministry of Natural Resources, East China Normal University, Shanghai, 200241, China
| | - Minsheng Huang
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, Institute of Eco-Chongming, Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area, Ministry of Natural Resources, East China Normal University, Shanghai, 200241, China
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31
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Liao R, Jin Z, Chen M, Li S. An integrated approach for enhancing the overall performance of constructed wetlands in urban areas. WATER RESEARCH 2020; 187:116443. [PMID: 32979580 DOI: 10.1016/j.watres.2020.116443] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 09/07/2020] [Accepted: 09/20/2020] [Indexed: 06/11/2023]
Abstract
Constructed wetlands (CWs) are an important component of the urban matrix and play an essential role in the restoration of urban ecological environments. Although existing studies have mainly focused on the efficiency of technologies for removing pollutants in wastewater, efforts to intensify the overall performance of CWs have not been reported. Here, we propose a novel theoretical scheme for promoting optimal overall performance of CWs through the development of an integrated approach, entailing simulation, evaluation, and optimization strategies for their management. We successfully simulated the water distribution system of the Yanfangdian CW in Beijing, China, applying 42 hydrological parameters within the MIKE 21 software. We further evaluated our simulation results by performing an analytic hierarchy process to calculate performance scores. The back propagation neural network was well trained to quantify the relationship between the hydrological parameters and the overall performance of CW based on its water distribution characteristics and their corresponding scores. Subsequently, a genetic algorithm was applied to determine the hydrological solution. A strategy for optimizing the water level and flow was formulated for improving the ecological, purification and storage performances of the targeted CW along with a flexible strategy for ensuring its proper functioning. Our approach provides a robust and universal platform that can contribute significantly to the advancement of CWs that have a wide range of applications and could be extended to other ecosystems.
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Affiliation(s)
- Renkuan Liao
- State Key Laboratory of Simulation and Regulation of Water Cycles in River Basins, China Institute of Water Resources and Hydropower Research, Beijing 100048, PR China; Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Zhengyuan Jin
- College of Water Conservancy and Civil Engineering, China Agricultural University, Beijing 100083, PR China
| | - Minghong Chen
- College of Water Conservancy and Civil Engineering, China Agricultural University, Beijing 100083, PR China
| | - Shuqin Li
- College of Water Conservancy and Civil Engineering, China Agricultural University, Beijing 100083, PR China.
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32
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Ma Y, Zheng P, Dai W, Zheng X, He S, Zhao M. Pathways regulating nitrogen removal in constructed ditch wetlands: effects of different inflow ratios and artificial aeration. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:42571-42581. [PMID: 32712934 DOI: 10.1007/s11356-020-10224-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 07/20/2020] [Indexed: 06/11/2023]
Abstract
Constructed ditch wetland (CDW) is a combination of idle ditch and constructed wetland, which is typically used in rural areas to remove pollutants from domestic wastewater. However, its low total nitrogen (TN) removal remains a pressing issue. To enhance total nitrogen removal, an approach of supplying water at two locations in the CDW at different influent flow ratios, combined with artificial aeration, was proposed to adjust carbon and oxygen distribution in the system. The highest average TN removal was achieved at low influent concentration (CDW4; influent flow ratio 1:2). The removal of TN in winter and spring were 58.93 and 83.26%, respectively. The distribution of carbon sources in the back zone enhanced denitrification. Of the high influent concentration treatments, CDW2 (2:1) achieved 16.97% more TN removal on average compared with CDW1 (3:0), after extra artificial aeration was applied in the front zone. However, nitrification was a limiting step in the system, which became the primary problem preventing pollutant purification. Moreover, nitrifying bacteria abundance was negatively correlated to the influent flow ratio and autotrophic denitrifying bacterial abundance was positively correlated to the influent flow ratios. Graphical abstract.
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Affiliation(s)
- Yuhui Ma
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Peiru Zheng
- School of Life and Environmental Science, Wenzhou University, Wenzhou, 325000, China
| | - Wanqing Dai
- School of Life and Environmental Science, Wenzhou University, Wenzhou, 325000, China
| | - Xiangyong Zheng
- School of Life and Environmental Science, Wenzhou University, Wenzhou, 325000, China.
| | - Shengbing He
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China.
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China.
| | - Min Zhao
- School of Life and Environmental Science, Wenzhou University, Wenzhou, 325000, China
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Lu J, Guo Z, Kang Y, Fan J, Zhang J. Recent advances in the enhanced nitrogen removal by oxygen-increasing technology in constructed wetlands. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2020; 205:111330. [PMID: 32977288 DOI: 10.1016/j.ecoenv.2020.111330] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 09/05/2020] [Accepted: 09/09/2020] [Indexed: 06/11/2023]
Abstract
Constructed wetland has attracted more and more attention for wastewater purification due to its low construction cost and convenient operation recently. However, the unique waterflooding structure of constructed wetland makes the low dissolved oxygen level, which limits the effect of nitrogen removal in the system. Therefore, it is necessary to develop the oxygen-increasing technology to overcome the drawback in constructed wetlands. In this review, the mechanism of nitrogen removal in constructed wetland is discussed and oxygen is main influence factor is concluded. In addition, oxygen-increasing technologies in recent advances which improve the nitrogen removal efficiency greatly, are emphatically introduced. Finally, some future perspectives about oxygen-increasing techniques are also put forward in order to provide reference for further research and engineering application.
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Affiliation(s)
- Jiaxing Lu
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, 266237, China
| | - Zizhang Guo
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, 266237, China.
| | - Yan Kang
- College of Environment and Safety Engineering, Qingdao University of Science and Technology, Qingdao, 266042, China
| | - Jinlin Fan
- Department of Science and Technology Management, Shandong University, Jinan, 250100, China
| | - Jian Zhang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, 266237, China.
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34
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Wu Q, Xiao J, Fu L, Ma M, Peng S. Microporous intermittent aeration vertical flow constructed wetlands for eutrophic water improvement. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:16574-16583. [PMID: 32125639 DOI: 10.1007/s11356-020-08067-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 02/11/2020] [Indexed: 06/10/2023]
Abstract
To enhance eutrophic water improvement effect, three parallel lab-scale oxidation pond-vertical subsurface flow constructed wetland-stable pond combined systems with different microporous intermittent aeration positions were constructed. The purification effect of each system was determined, and the contribution rate of each part of the system was also calculated. The characters of bacterial community under different aeration positions were also analyzed. Microporous intermittent aeration rate of 5 mg/L was chosen as the aeration rate for follow-up experiment. The result showed that the best CODCr, total nitrogen, and total phosphorus removal efficiencies were achieved by the combined system with bottom microporous intermittent aeration, and the efficiencies were 71.04%, 79.52%, and 95.10%, respectively. The best ammonium nitrogen removal efficiency was 92.62% and was achieved by the combined system with surface microporous intermittent aeration. After analyses, 14 strains of bacteria associated with the removal of N elements were found and 8 strains of bacteria associated with P element cycle were found.
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Affiliation(s)
- Qing Wu
- School of Environmental Science and Engineering, Tianjin University, No. 135 Yaguan Road, Jinnan District, Tianjin, 300350, China.
| | - Jingjing Xiao
- School of Environmental Science and Engineering, Tianjin University, No. 135 Yaguan Road, Jinnan District, Tianjin, 300350, China
| | - Lijuan Fu
- School of Environmental Science and Engineering, Tianjin University, No. 135 Yaguan Road, Jinnan District, Tianjin, 300350, China
| | - Mengxing Ma
- School of Environmental Science and Engineering, Tianjin University, No. 135 Yaguan Road, Jinnan District, Tianjin, 300350, China
| | - Sen Peng
- School of Environmental Science and Engineering, Tianjin University, No. 135 Yaguan Road, Jinnan District, Tianjin, 300350, China
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35
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Recent Advances in the Application, Design, and Operations & Maintenance of Aerated Treatment Wetlands. WATER 2020. [DOI: 10.3390/w12041188] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
This paper outlines recent advances in the design, application, and operations and maintenance (O&M) of aerated treatment wetland systems as well as current research trends. We provide the first-ever comprehensive estimate of the number and geographical distribution of aerated treatment wetlands worldwide and review new developments in aerated wetland design and application. This paper also presents and discusses first-hand experiences and challenges with the O&M of full-scale aerated treatment wetland systems, which is an important aspect that is currently not well reported in the literature. Knowledge gaps and suggestions for future research on aerated treatment wetlands are provided.
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36
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Feng L, Liu Y, Zhang J, Li C, Wu H. Dynamic variation in nitrogen removal of constructed wetlands modified by biochar for treating secondary livestock effluent under varying oxygen supplying conditions. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2020; 260:110152. [PMID: 32090842 DOI: 10.1016/j.jenvman.2020.110152] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 01/13/2020] [Accepted: 01/14/2020] [Indexed: 06/10/2023]
Abstract
Vertical flow constructed wetlands are facing the problem of low removal efficiency when treating high-load wastewater. This study explored the effect of oxygen supplement (1.2, 1.0, 0.8 L min-1 for 6 h; 1.0 L min-1 for 4 h and 2 h) on enhancing nitrogen removal in vertical flow constructed wetlands modified by adding biochar for treating secondary livestock effluent. The results indicated that biochar addition could enhance contaminant removal due to its adsorption of contaminants under the condition of no aeration. Additionally, the aeration addition of 1.0 L min-1 for 2 h per day in biochar-based constructed wetlands achieved the high efficiencies for chemical oxygen demand (95%) and total nitrogen (73%) removal. However, total nitrogen removal efficiency in biochar-based constructed wetlands declined under excessive dissolved oxygen conditions which might restrain the denitrification process. Average nitrous oxide emission fluxes in biochar-based constructed wetlands (575-1877 μg m-2 h-1) were lower than those in non-biochar constructed wetlands (745-2298 μg m-2 h-1). In addition, the variation of N2O emission under different aeration conditions was similar with the maximum value at the aeration condition of 1.2 L min-1 for 6 h d-1. These results could be useful for improving the sustainable design and operation of constructed wetlands for high-load wastewater treatments.
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Affiliation(s)
- Likui Feng
- School of Environment and Planning, Liaocheng University, Liaocheng, Shandong, 252000, PR China; College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi, 712100, PR China
| | - Yang Liu
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi, 712100, PR China
| | - Jinyong Zhang
- Environmental Engineering Co., Ltd of Shandong Academy of Environmental Sciences, Jinan, Shandong, 250013, PR China
| | - Cong Li
- School of Environment and Planning, Liaocheng University, Liaocheng, Shandong, 252000, PR China.
| | - Haiming Wu
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi, 712100, PR China.
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Zhu D, Cheng X, Sample DJ, Yazdi MN. Effect of intermittent aeration mode on nitrogen concentration in the water column and sediment pore water of aquaculture ponds. J Environ Sci (China) 2020; 90:331-342. [PMID: 32081329 DOI: 10.1016/j.jes.2019.11.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 10/25/2019] [Accepted: 11/26/2019] [Indexed: 06/10/2023]
Abstract
Nitrogen in pond sediments is a major water quality concern and can impact the productivity of aquaculture. Dissolved oxygen is an important factor for improving water quality and boosting fish growth in aquaculture ponds, and plays an important role in the conversion of ammonium-nitrogen (NH4+-N) to nitrite-nitrogen (NO2--N) and eventually nitrate-nitrogen (NO3--N). A central goal of the study was to identify the best aeration method and strategy for improving water quality in aquaculture ponds. We conducted an experiment with six tanks, each with a different aeration mode to simulate the behavior of aquaculture ponds. The results show that a 36 hr aeration interval (Tc = 36 hr: 36 hr) and no aeration resulted in high concentrations of NH4+-N in the water column. Using a 12 hr interval time (Tc = 12 hr: 12 hr) resulted in higher NO2--N and NO3--N concentrations than any other aeration mode. Results from an 8 hr interval time (Tc = 8 hr: 8 hr) and 24 hr interval time (Tc = 24 hr: 24 hr) were comparable with those of continuous aeration, and had the benefit of being in use for only half of the time, consequently reducing energy consumption.
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Affiliation(s)
- Dantong Zhu
- State Key Laboratory of Subtropical Building Science, South China University of Technology, Guangzhou 510640, China; School of Civil Engineering and Transportation, South China University of Technology, Guangzhou 510640, China; Department of Biological System Engineering, Virginia Polytechnic Institute and State University, Virginia Beach 23455, United States
| | - Xiangju Cheng
- State Key Laboratory of Subtropical Building Science, South China University of Technology, Guangzhou 510640, China; School of Civil Engineering and Transportation, South China University of Technology, Guangzhou 510640, China
| | - David J Sample
- Department of Biological System Engineering, Virginia Polytechnic Institute and State University, Virginia Beach 23455, United States.
| | - Mohammad Nayeb Yazdi
- Department of Biological System Engineering, Virginia Polytechnic Institute and State University, Virginia Beach 23455, United States
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Lin CJ, Chyan JM, Zhuang WX, Vega FA, Mendoza RMO, Senoro DB, Shiu RF, Liao CH, Huang DJ. Application of an innovative front aeration and internal recirculation strategy to improve the removal of pollutants in subsurface flow constructed wetlands. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2020; 256:109873. [PMID: 31822455 DOI: 10.1016/j.jenvman.2019.109873] [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: 03/31/2019] [Revised: 11/06/2019] [Accepted: 11/13/2019] [Indexed: 06/10/2023]
Abstract
The pollutant removal performance of traditional horizontal subsurface flow (HSSF) constructed wetlands (CWs) is limited because of the dissolved oxygen (DO) supply is insufficient. The aeration of HSSF CWs usually improves their pollutant removal performance, but a high DO induces the accumulation of nitrate-nitrogen (NO3--N) and suppresses the improvement of total nitrogen (TN) removal. In this study, an integrated solution that involved in-tank front aeration and internal recirculation (FAIR) was used to improve the pollutant removal performance of HSSF CWs. Based on the experimental results, the FAIR system significantly increased the removal efficiencies of biochemical oxygen demand (BOD) from 53.8-76.0% to 82.0-91.7% and reduced the BOD concentration in the effluent to below 10 mg L-1. The removal efficiency of ammonia-nitrogen (NH3-N) increased from 15.1-78.3% to 98.5-98.6% while the removal efficiencies of the total Kjeldahl nitrogen (TKN) of the control and FAIR HSSF CWs were 18.2-77.1% and 93.5-94.3%, respectively. HSSF CWs with FAIR outperformed aerated HSSF CWs in the removal of NH3-N and TKN. The effects of two recirculation flow ratios (Rr = recirculation flow rate/influent flow rate), 14.3 and 3.0, on the improvement of pollutant removal performance were investigated. The lower Rr did not significantly affect the improvement of BOD, NH3-N, and TKN, but a higher Rr resulted in more severe accumulation of NO3--N. The removal efficiency of TN in control HSSF CWs ranged from 20.4% to 75.5%, and in the FAIR HSSF CW was 71.6% for Rr = 14.3 and 81.3% for Rr = 3.0. However, the FAIR system did not enhance the removal performance of total phosphorus, suggesting that the DO level and internal recirculation were not dominant mechanisms for the removal of phosphorous. The easy maintenance of the FAIR system made it a superior modification for improving the pollutant removal performance of HSSF CWs.
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Affiliation(s)
- Chien Jung Lin
- Department of Environmental Resources Management, Chia Nan University of Pharmacy and Science, Tainan, 71710, Taiwan, ROC.
| | - Jih Ming Chyan
- Department of Environmental Resources Management, Chia Nan University of Pharmacy and Science, Tainan, 71710, Taiwan, ROC.
| | - Wen Xue Zhuang
- Department of Environmental Resources Management, Chia Nan University of Pharmacy and Science, Tainan, 71710, Taiwan, ROC.
| | - Floradelle Aboga Vega
- Camarines Norte State College, Daet 4600 Camarines Norte, Philippines; Graduate School of Engineering, Adamson University, Ermita 1000, Manila, Philippines.
| | - Rose Marie O Mendoza
- Department of Environmental Science and Engineering, Adamson University, Ermita 1000, Manila, Philippines.
| | - Delia B Senoro
- Civil Engineering and Environmental Engineering, Mapua University, Manila, 1101, Philippines.
| | - Ruei Feng Shiu
- Bioengineering, University of California, Merced, CA, USA.
| | - Chih Hsiang Liao
- Department of Environmental Resources Management, Chia Nan University of Pharmacy and Science, Tainan, 71710, Taiwan, ROC.
| | - Da Ji Huang
- Department of Environmental Resources Management, Chia Nan University of Pharmacy and Science, Tainan, 71710, Taiwan, ROC.
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39
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The combined effect of dissolved oxygen and COD/N on nitrogen removal and the corresponding mechanisms in intermittent aeration constructed wetlands. Biochem Eng J 2020. [DOI: 10.1016/j.bej.2019.107400] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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40
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Zhuang LL, Yang T, Zhang J, Li X. The configuration, purification effect and mechanism of intensified constructed wetland for wastewater treatment from the aspect of nitrogen removal: A review. BIORESOURCE TECHNOLOGY 2019; 293:122086. [PMID: 31495460 DOI: 10.1016/j.biortech.2019.122086] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 08/26/2019] [Accepted: 08/27/2019] [Indexed: 05/10/2023]
Abstract
Constructed wetland (CW) for wastewater treatment has attracted increasing attention. In this review, the system configuration optimization, purification effect and general mechanisms of nitrogen removal in CW are systematically summarized and discussed. Ammonia oxidation is a crucial and primary process for total nitrogen (TN) removal in domestic or livestock wastewater treatment. Aeration, waterdrop influent and tidal operation are three main methods to strengthen the oxygen supplement and nitrification process in CW. Aeration significantly increases the ammonia removal rate (almost 100%), followed by the removal of chemical oxygen demand (COD) and TN. Solid carbon source, iron and anode material can be filled as electron donor for the denitrification process. The co-adjustment of oxygen and carbon/electron donor can form different conditions for different nitrogen removal pathways (e.g. the simultaneous nitrification-denitrification, the partial nitrification-denitrification and the anammox process), and achieve the optimal removal of nitrogen.
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Affiliation(s)
- Lin-Lan Zhuang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science & Engineering, Shandong University, Qingdao 266237, China
| | - Ting Yang
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China
| | - Jian Zhang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science & Engineering, Shandong University, Qingdao 266237, China.
| | - Xiangzheng Li
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science & Engineering, Shandong University, Qingdao 266237, China
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41
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Impact of Aeration on the Removal of Organic Matter and Nitrogen Compounds in Constructed Wetlands Treating the Liquid Fraction of Piggery Manure. APPLIED SCIENCES-BASEL 2019. [DOI: 10.3390/app9204310] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The increasing demand for sustainable, robust and cost-efficient wastewater treatment techniques strengthen the implementation of constructed wetlands (CWs) in the agricultural sector. In countries like Belgium (Flanders), the compliance of strict water quality standards and surface area requirements have hindered considerably their application. New wetland designs such as aerated CWs, could help to overcome these challenges. This study evaluated the capacity of artificially aerated mesocosm systems to decrease chemical oxygen demand (COD) concentrations below the 125 mgO2/L limit imposed on installations treating animal manure. The treatment of this high-strength wastewater has been slightly studied via aerated CWs. A three-stage experiment investigated the effect of constant, intermittent and non-aeration regimes on: ammonium volatilisation, the evolution of organic and nitrogen compounds concentrations, and denitrification. The results were assessed through a mixed modelling procedure using SAS 9.4 software. A COD removal between 65% and 58% in constantly and intermittent aerated systems, versus 27% COD removal in the non-aerated system indicated the effectiveness of aeration. However, a dissimilarity was encountered in the removal of nitrogen compounds, resulting in an 82% decrease of nitrate concentrations in the non-aerated system, versus 0.5% and 11% in the aerated ones. Based on the results, this experimental set-up adjusted to field operational conditions can prove that aerated CWs can treat the liquid fraction of piggery manure.
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Li D, Wang X, Chi L, Wang J. The design and operation of subsurface wastewater infiltration systems for domestic wastewater. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2019; 91:843-854. [PMID: 30844095 DOI: 10.1002/wer.1098] [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: 01/21/2019] [Revised: 02/21/2019] [Accepted: 02/23/2019] [Indexed: 06/09/2023]
Abstract
Throughout rural regions, large amounts of domestic wastewater are discharged into natural bodies of water without treatment. A well-designed subsurface wastewater infiltration (SWI) system is an effective wastewater pollution removal strategy for small and remote communities due to its low energy consumption, low operational cost, and good performance. This paper describes the types of structures and purification mechanisms of SWI systems, focusing on the design of substrate materials and the optimization of different operation modes including the hydraulic loading rate, pollutant loading rate, intermittent operation, aeration, and shunting distribution. The challenges and trends in the development of SWI systems are also discussed. PRACTITIONER POINTS: The construction and purification mechanisms of SWI system are described. The design of substrates and the optimization of operation modes are focused. The challenges and the development trends for the system are further introduced.
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Affiliation(s)
- Dan Li
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Xinze Wang
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Lina Chi
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Jie Wang
- The Center for Sustainable Development and Global Competitiveness (CSDGC), Stanford University, Stanford, California
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Liu G, He T, Liu Y, Chen Z, Li L, Huang Q, Xie Z, Xie Y, Wu L, Liu J. Study on the purification effect of aeration-enhanced horizontal subsurface-flow constructed wetland on polluted urban river water. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:12867-12880. [PMID: 30891700 DOI: 10.1007/s11356-019-04832-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Accepted: 03/08/2019] [Indexed: 06/09/2023]
Abstract
The issue of urban river pollution has attracted great attention due to high concentrations of ammonia nitrogen (NH4+-N) and low concentrations of dissolved oxygen (DO) in polluted water bodies. In order to investigate the effects of aeration-enhanced horizontal subsurface-flow constructed wetlands on polluted river water, unaerated aeration (NA), continuous aeration (CA), and intermittent aeration (IA) constructed wetlands were established. The purification effects of the wetland on various pollutants and the form of effluent nitrogen, influences of temperature on the removal rates of pollutants, the change of redox potential-oxidation reduction potential (ORP)-and the difference of dissolved oxygen (DO) between influent and effluent were investigated. The results indicated that aeration enhancement can improve the purification efficiencies of chemical oxygen demand (COD) and NH4+-N in constructed wetlands. The purification efficiencies of TN in IA and CA constructed wetlands were 91.9% and 53.7%, respectively, indicating that IA is the optimized aeration method for removal of various pollutants in wetlands. Changes of DO and ORP in effluent under IA and CA suggested improvement of aeration on the water environment. Meanwhile, DO was more sensitive to temperature compared with ORP. Additionally, a study of the nitrogen content in effluent suggested that the aeration method had a significant influence on the nitrogen content in effluent. The removal rates of both NH4+-N and TN degraded as the temperature dropped. The results also demonstrated that the removal rate of NH4+-N under aeration condition was more sensitive to temperature than that under NA condition and the effect of temperature on the removal rate of NH4+-N was greater than that of TN.
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Affiliation(s)
- Guo Liu
- State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu, 610059, People's Republic of China
- College of Environment and Ecology, Chengdu University of Technology, Chengdu, 610059, People's Republic of China
| | - Tianyu He
- State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu, 610059, People's Republic of China
- College of Environment and Ecology, Chengdu University of Technology, Chengdu, 610059, People's Republic of China
| | - Yanhui Liu
- State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu, 610059, People's Republic of China
- College of Environment and Civil Engineering, Chengdu University of Technology, Chengdu, 610059, People's Republic of China
| | - Zhengyang Chen
- College of Environment and Ecology, Chengdu University of Technology, Chengdu, 610059, People's Republic of China
- Chengdu environmental group Chengdu tap water Co., Ltd., Chengdu, 610000, People's Republic of China
| | - Lijuan Li
- College of Environment and Civil Engineering, Chengdu University of Technology, Chengdu, 610059, People's Republic of China
| | - Qinqin Huang
- State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu, 610059, People's Republic of China
- College of Environment and Civil Engineering, Chengdu University of Technology, Chengdu, 610059, People's Republic of China
| | - Zhihao Xie
- State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu, 610059, People's Republic of China
- College of Environment and Ecology, Chengdu University of Technology, Chengdu, 610059, People's Republic of China
| | - Yifei Xie
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610059, People's Republic of China
| | - Lishan Wu
- State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu, 610059, People's Republic of China
- College of Environment and Ecology, Chengdu University of Technology, Chengdu, 610059, People's Republic of China
| | - Jing Liu
- State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu, 610059, People's Republic of China.
- College of Environment and Ecology, Chengdu University of Technology, Chengdu, 610059, People's Republic of China.
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Zheng F, Huang L, Pan J, Qi S, Tan C, Xiao L. Effect of aeration and hydraulic loading rate on nitrogen removal by subsurface infiltration systems. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2019; 91:399-406. [PMID: 30784134 DOI: 10.1002/wer.1030] [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: 07/15/2018] [Revised: 09/29/2018] [Accepted: 10/19/2018] [Indexed: 06/09/2023]
Abstract
This study investigated the effect of hydraulic loading rate (HLR) on matrix dissolved oxygen (DO), organic matter removal, nitrogen removal, N2 O emissions, and the abundances of functional genes participating in nitrogen removal in intermittent aerated mode (IAM) and nonaerated mode (NAM) subsurface infiltration systems (SISs). In contrast to NAM SISs, IAM SISs were able to create aerobic conditions in the upper matrix (above 50 cm depth) and anoxic or anaerobic conditions in the lower matrix (below 80 cm depth). Subsequently, this enhanced the abundance of functional genes related to nitrogen removal. Chemical oxygen demand (COD) and nitrogen removal performance were significantly higher under IAM SISs than with NAM SISs. Under a HLR of 0.3 m3 /(m2 d), the IAM SIS was able to achieve low N2 O emissions (12.6 mg/[m2 d]) along with removal efficiencies of 90.5%, 91.4%, and 85.7% for COD, ammonia nitrogen ( NH 4 + -N), and total nitrogen (TN), respectively. PRACTITIONER POINTS: Intermittent aeration successfully realized sequential aerobic and anaerobic conditions at 50 cm depth and at 80 and 110 cm depths of a subsurface infiltration system. Intermittent aeration reduced N2 O emissions and improved hydraulic loading rate and organic matter, nitrogen removal efficiencies. Intermittent aeration enhanced the abundances of amoA, nxrA, napA, narG, nirS, nirK, qnorB, and nosZ.
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Affiliation(s)
- Fanping Zheng
- College of Life Science, Shenyang Normal University, Shenyang, China
| | - Linli Huang
- College of Life Science, Shenyang Normal University, Shenyang, China
| | - Jing Pan
- College of Life Science, Shenyang Normal University, Shenyang, China
| | - Shiyue Qi
- College of Life Science, Shenyang Normal University, Shenyang, China
| | - Chaoquan Tan
- College of Life Science, Shenyang Normal University, Shenyang, China
| | - Lu Xiao
- College of Life Science, Shenyang Normal University, Shenyang, China
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Zhao Y, Zhang Z, Li Z, Wang S, Tan C, Fan L, Pan J. Does intermittent aeration and/or an influent distributary affect nitrogen removal and nitrous oxide emission of an ecological soil wastewater infiltration system? WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2019; 79:1417-1425. [PMID: 31123241 DOI: 10.2166/wst.2019.144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The effect of intermittent aeration and an influent distributary on NH4 +-N removal, total nitrogen (TN) removal, nitrous oxide (N2O) emission and the abundances of nitrogen removal and N2O emission functional genes in four types of ecological soil wastewater infiltration systems (ESWISs) (which were conventional ESWIS 1 (operated without aeration and influent distributary), ESWIS 2 (operated with intermittent aeration), ESWIS 3 (operated with influent distributary) and ESWIS 4 (operated with intermittent aeration and influent distributary)) were studied. Intermittent aeration in ESWIS 2 and 4 created aerobic conditions above 50 cm depth of the matrix and anoxic or anaerobic conditions in the lower matrix (below 80 cm depth). ESWIS 4 improved NH4 +-N (to 90.1%) and TN (to 87.8%) removal efficiencies and increased the abundances of eight nitrogen removal and N2O emission functional genes (amoA, nxrA, narG, napA, nirS, nirK, qnorB and nosZ) in contrast with other ESWISs. The combination of intermittent aeration and influent distributary achieved the lowest N2O emission rate of 34.7 mg/(m2 d) in ESWIS 4. Intermittent aeration combined with influent distributary was recommended for ESWISs to enhance nitrogen removal and reduce N2O emission.
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Affiliation(s)
- Yue Zhao
- College of Life Science, Shenyang Normal University, Shenyang 110034, China E-mail:
| | - Zhiyu Zhang
- College of Life Science, Shenyang Normal University, Shenyang 110034, China E-mail:
| | - Ziqi Li
- College of Life Science, Shenyang Normal University, Shenyang 110034, China E-mail:
| | - Shiyao Wang
- College of Life Science, Shenyang Normal University, Shenyang 110034, China E-mail:
| | - Chaoquan Tan
- College of Life Science, Shenyang Normal University, Shenyang 110034, China E-mail:
| | - Linlin Fan
- College of Life Science, Shenyang Normal University, Shenyang 110034, China E-mail:
| | - Jing Pan
- College of Life Science, Shenyang Normal University, Shenyang 110034, China E-mail:
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Nivala J, Boog J, Headley T, Aubron T, Wallace S, Brix H, Mothes S, van Afferden M, Müller RA. Side-by-side comparison of 15 pilot-scale conventional and intensified subsurface flow wetlands for treatment of domestic wastewater. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 658:1500-1513. [PMID: 30678008 DOI: 10.1016/j.scitotenv.2018.12.165] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 12/11/2018] [Accepted: 12/11/2018] [Indexed: 06/09/2023]
Abstract
This study reports a systematic assessment of treatment efficacy for 15 pilot-scale subsurface flow constructed wetlands of different designs for CBOD5, TSS, TOC, TN, NH4-N, NO3-N, NO2-N, and E. coli over the course of one year in an outdoor study to evaluate the effects of design and plants. The systems consisted of a range of designs: horizontal flow (HF) with 50 and 25 cm depth, unsaturated vertical flow (VF) with sand or fine gravel, and intensified systems (horizontal and saturated vertical flow with aeration, and reciprocating fill and drain). Each system was built in duplicate: one was planted with Phragmites and one was left unplanted (with the exception of the reciprocating system, of which there was only one and it was unplanted). All systems were fed with the same primary-treated domestic wastewater. Effluent concentrations, areal and volumetric mass removal rates, and percent mass removal for the 15 systems are discussed. HF wetlands removed CBOD5, TSS, TN, NH4-N and E. coli by 73-83%, 93-95%, 17-41%, 0-27% and 1.5 log units, respectively. Unsaturated VF and aerated VF wetlands removed CBOD5, TSS, TN, NH4-N and E. coli by 69-99%, 76-99%, 17-40%, 69-99% and 0.9-2.4 log units, respectively. The aerated HF and reciprocating systems removed CBOD5, TSS, TN, NH4-N and E. coli by 99%, 99%, 43-70%, 94-99% and 3.0-3.8 log units, respectively. The aerated HF and reciprocating systems achieved the highest TN removal rate of all of the designs. Design complexity clearly enhanced treatment efficacy (HF < VF < Intensified, p < 0.001) during the first two years of plant growth while the presence of plants had minor effects on TN and NH4-N removal in the shallow HF design only.
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Affiliation(s)
- Jaime Nivala
- Helmholtz Center for Environmental Research (UFZ), Environmental and Biotechnology Center (UBZ), Permoserstrasse 15, 04318 Leipzig, Germany.
| | - Johannes Boog
- Helmholtz Center for Environmental Research (UFZ), Environmental and Biotechnology Center (UBZ), Permoserstrasse 15, 04318 Leipzig, Germany
| | - Tom Headley
- Wetland and Ecological Treatment Systems Ltd, Maitland, NSW, Australia
| | - Thomas Aubron
- Helmholtz Center for Environmental Research (UFZ), Environmental and Biotechnology Center (UBZ), Permoserstrasse 15, 04318 Leipzig, Germany
| | - Scott Wallace
- Naturally Wallace Consulting LLC, P.O. Box 37, Stillwater, MN 55082, USA
| | - Hans Brix
- Department of Bioscience, Aquatic Biology, Aarhus University, Ole Worms Allé 1, 8000 Aarhus C, Denmark
| | - Sibylle Mothes
- Helmholtz Center for Environmental Research (UFZ), Department Analytical Chemistry, Permoserstrasse 15, 04318 Leipzig, Germany
| | - Manfred van Afferden
- Helmholtz Center for Environmental Research (UFZ), Environmental and Biotechnology Center (UBZ), Permoserstrasse 15, 04318 Leipzig, Germany
| | - Roland A Müller
- Helmholtz Center for Environmental Research (UFZ), Environmental and Biotechnology Center (UBZ), Permoserstrasse 15, 04318 Leipzig, Germany
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Liu FF, Fan J, Du J, Shi X, Zhang J, Shen Y. Intensified nitrogen transformation in intermittently aerated constructed wetlands: Removal pathways and microbial response mechanism. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 650:2880-2887. [PMID: 30373064 DOI: 10.1016/j.scitotenv.2018.10.037] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 09/29/2018] [Accepted: 10/03/2018] [Indexed: 06/08/2023]
Abstract
Nitrogen (N) removal processing in vertical flow constructed wetlands (VFCWs) with different designs often varies greatly. Here, a long term VFCWs study for domestic wastewater treatment was carried out to investigate the impact of intermittent aeration and three construction-waste media (common gravel, red brick and fly-ash brick) on N loss, N retention and microbial community. The total nitrogen (TN) removal was significantly higher in aerated VFCWs (91.31%-93.91%) compared with non-aerated VFCWs (12.22%-53.92%), with the highest removal rate in system VI filled with fly-ash brick. Nitrification/denitrification was the main N sink in aerated VFCWs accounting for 36.79%-55.44%, while media storage (8.47%-48.64%) dominated in non-aerated systems because of nitrification limitation. <16% of the TN removal was uptake by plants, and N2O emission contributed about 0.08%-0.39%. Microbial study found that functional bacteria increased with intermittently aeration. The analysis revealed the crucial influence of oxygen supply and media on N transformations in VFCWs.
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Affiliation(s)
- Fei-Fei Liu
- Institute of Marine Science and Technology, Shandong University, Qingdao 266237, PR China
| | - Jinlin Fan
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science & Engineering, Shandong University, Jinan 250100, PR China
| | - Jinhui Du
- Shandong Academy of Environmental Science, Jinan 250061, PR China
| | - Xia Shi
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science & Engineering, Shandong University, Jinan 250100, PR China
| | - Jian Zhang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science & Engineering, Shandong University, Jinan 250100, PR China.
| | - Youhao Shen
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science & Engineering, Shandong University, Jinan 250100, PR China
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Jia L, Gou E, Liu H, Lu S, Wu S, Wu H. Exploring Utilization of Recycled Agricultural Biomass in Constructed Wetlands: Characterization of the Driving Force for High-Rate Nitrogen Removal. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:1258-1268. [PMID: 30608662 DOI: 10.1021/acs.est.8b04871] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Improper treatment of various wastewaters with a low C/N ratio and management of abundant agricultural wastes may pose a serious threat to bodies of water and agricultural ecosystems in rural areas, especially in developing countries. Thus, a potential alternative for simultaneous mitigation of this pollution is needed to protect rural environments. This study investigated the feasibility and enhanced performance of applying typical agricultural wastes (such as wheat straw, apricot pits, and walnut shells) as carbon sources for nitrogen removal in constructed wetlands (CWs). The leaching experiment employed fluorescence excitation-emission spectrophotometry and revealed that the wheat straw material had the highest capability of carbon release with an average dissolved organic carbon release content and rate of 27.88 mg g-1 and 5.24 mg g-1 day-1, respectively. Dissolved organic matter released from different agricultural wastes mainly consisted of humic acid-like and fulvic acid-like compounds. Long-term assessment of lab-scale intermittent aeration CWs receiving agricultural wastes revealed a high total nitrogen removal of 66.75-93.67% in low carbon/nitrogen ratio wastewaters (C/N = 3). These findings can contribute to a better understanding of the driving mechanism through which agricultural wastes enhance nitrogen removal in CW wastewater treatments.
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Affiliation(s)
- Lixia Jia
- College of Resources and Environment , Northwest A&F University , Yangling , Shaanxi 712100 , PR China
| | - Enfang Gou
- State Key Laboratory of Urban Water Resources and Environment , Harbin Institute of Technology , Harbin 150090 , PR China
| | - Hai Liu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment , Tsinghua University , Beijing 100084 , PR China
| | - Shaoyong Lu
- National Engineering Laboratory for Lake Pollution Control and Ecological Restoration , Chinese Research Academy of Environmental Sciences , Beijing 100012 , PR China
| | - Shubiao Wu
- College of Resources and Environment , Northwest A&F University , Yangling , Shaanxi 712100 , PR China
- Aarhus Institute of Advanced Studies , Aarhus University , Aarhus 8000C , Denmark
| | - Haiming Wu
- College of Resources and Environment , Northwest A&F University , Yangling , Shaanxi 712100 , PR China
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Liang C, Li Y, Chai B, Wu H. Evaluating the effects of intermittent aeration and biochar addition on enhancing removal performance of subsurface wastewater infiltration systems with loess soil. ACTA ACUST UNITED AC 2019. [DOI: 10.1016/j.biteb.2018.11.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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Chai H, Li W, Shao Z, Li L, He Q. Pollutant removal performance of an integrated system that combines a baffled vertical-flow wetland and a scenic water body. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:269-281. [PMID: 30392174 DOI: 10.1007/s11356-018-3507-8] [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: 08/10/2018] [Accepted: 10/16/2018] [Indexed: 06/08/2023]
Abstract
Stormwater treatment requires effective control measures and development of low-cost and high-efficiency technologies. An integrated system is developed by combining a baffled vertical-flow constructed wetland (BVFCW) and a scenic water body for stormwater quality control purpose. The objectives of the study are to compare the pollutant removal performance of the full-scale integrated system with four groups of wetland-to-scenic water body area ratios (WSARs) including 1/11, 2/11, 3/11, 4/11 and investigate its treatment efficiency. Results show that the system performs better in the removal of chemical oxygen demand (COD), total nitrogen (TN), ammonia nitrogen (NH4+-N), nitrate-nitrogen (NO3-N), and total phosphorus (TP) at the WSAR of 4/11 than that at 3/11 in sixteen-day operation, while it reaches the highest total nitrogen (TN) removal efficiency of 74.0% at the WSAR of 2/11 due to relatively rich carbon source and high influent TN concentration. The integrated system may prove the most effective COD removal at the WSAR of 4/11 for four-time aerobic/anaerobic alternating conditions, a longer flow path and more time to contact with substrates, although the influent COD is lower than that at 2/11 and 1/11. After sixteen-day operation, BVFCW achieved COD removal rate of 90.3%, NH4+-N removal rate of 85.7%, NO3-N removal rate of 68.6%, and TP removal rate of 52.5% at the WSAR of 4/11. At the WSAR of 1/11, effluent met the Class IV requirements in Chinese standards after one-week operation, while effluent met the Class III requirements under the rest conditions. Since effluent in all WSARs met the standards, WSARs of 1/11 and 2/11 were recommended.
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Affiliation(s)
- Hongxiang Chai
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China.
- National Centre for International Research of Low-Carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China.
| | - Wenqian Li
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China
- National Centre for International Research of Low-Carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China
| | - Zhiyu Shao
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China
- National Centre for International Research of Low-Carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China
| | - Liang Li
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China
- National Centre for International Research of Low-Carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China
| | - Qiang He
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, People's Republic of China
- National Centre for International Research of Low-Carbon and Green Buildings, Chongqing University, Chongqing, 400045, People's Republic of China
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