1
|
Chen R, Liu X, Wang J, Chen J, Wang X, Lv Y, Xu J, Wang S, Li D, He X, Hou J. Exploring organic matter conversion pathway and its effect on nitrogen removal in tidal flow constructed wetlands. CHEMOSPHERE 2024; 349:140927. [PMID: 38081523 DOI: 10.1016/j.chemosphere.2023.140927] [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: 10/08/2023] [Revised: 11/22/2023] [Accepted: 12/07/2023] [Indexed: 12/18/2023]
Abstract
Achieving effective nitrogen removal remains a significant challenge faced by constructed wetlands. Although organic matter is a crucial factor influencing nitrogen removal, little attention has been paid to the impact of organic matter conversion pathways on nitrogen removal in constructed wetlands. Here, we showed that endogenous microorganisms performing carbon internalization could be easily enriched in tidal flow constructed wetlands (TFCWs) under its special rhythmic cycle of anaerobic/aerobic operational mode. Endogenous microorganisms could translate influent carbon sources into intracellular carbons during the anaerobic stage and supply the carbon source for endogenous denitrification after the aerobic stage (rest period). Based on these findings, an innovative combined TFCW and Nitrifying-CW system was developed, and robust total nitrogen (TN) removal (82% on average) was achieved even under carbon source limiting conditions. This performance was a substantial improvement compared to the conventional single bed TFCW with multiple "tides" (corresponding to the multiple contact/rest periods) with TN removal of only 54% on average. Simultaneous nitrification-endogenous denitrification (SNED) was found to be the major nitrogen removal pathway in the proposed system. Compared with classical nitrification-denitrification, simultaneous nitrification-endogenous denitrification brings high nitrogen conversion rates and significantly reduces the demand for oxygen and organic carbon. Furthermore, microbial community analysis indicated that endogenous microorganisms such as Candidatus_Competibacter and Defluviicoccus were successfully enriched, accounting for 50.73% and 3.46% in CW1, and 25.25% and 1.76% in CW2, respectively. Together, these mechanisms allow the proposed system to achieve efficient TN removal.
Collapse
Affiliation(s)
- Ruiya Chen
- College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, China
| | - Xueyu Liu
- College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, China
| | - Jie Wang
- College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, China
| | - Jieyu Chen
- College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, China
| | - Xiaoning Wang
- College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, China
| | - Yabing Lv
- College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, China
| | - Juchen Xu
- College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, China
| | - Shaodi Wang
- 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; Key Laboratory of Aquaculture Facilities Engineering, Ministry of Agriculture and Rural Affairs, 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; Key Laboratory of Aquaculture Facilities Engineering, Ministry of Agriculture and Rural Affairs, 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; Key Laboratory of Aquaculture Facilities Engineering, Ministry of Agriculture and Rural Affairs, Wuhan, 430070, China.
| |
Collapse
|
2
|
Tan X, Zhao L, Li X, Liu YW, Lin TS, Wang YL. Enhanced treatment of low C/N ratio rural sewage by a modified multi-stage tidal flow constructed wetland at low temperature: Quantitative contributions of key functional genera. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 903:166249. [PMID: 37574076 DOI: 10.1016/j.scitotenv.2023.166249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 08/06/2023] [Accepted: 08/10/2023] [Indexed: 08/15/2023]
Abstract
Rural sewage treatment was traditionally faced contradiction between low-treatment rates and the need for low-cost development. To address this challenge, we explored the coupling of effluent circulation and step-feeding strategies in a multi-stage tidal flow constructed wetland (TFCW) to achieve stable nitrogen (N) removal performance under conditions of low carbon-to-nitrogen (C/N) ratios and low temperatures. The modified multi-stage TFCW demonstrated the ability to significantly reduce the concentrations of effluent NH4+-N and NO3--N by 33.9 % and 54.8 % respectively, resulting in values of 7.47 mg/L and 3.93 mg/L. Additionally, it achieved an average TN removal efficiency of 69.2 %. The improved N removal performance of rural sewage by the modified multi-stage TFCW at low temperatures was primarily attributed to autotrophic nitrification, heterotrophic nitrification, and autotrophic denitrification. Among the identified functional genera, Nitrosomonas and Nitrosospira played key roles as autotrophic nitrification bacteria (ANB), contributing to 28.2 % of NH4+-N removal. The key heterotrophic nitrification bacteria (HNB) Acidovorax and Rudaea were mainly responsible for 71.3 % of NH4+-N removal via the two-step ammonia assimilation through the organic nitrogen pathway. Furthermore, Rhodanobacter and Acinetobacter emerged as key autotrophic denitrification bacteria (ADNB), accounting for 79.9 % of NO3--N conversion and removal. In summary, this study provides valuable theoretical insights and supports ongoing efforts in biological regulation to address the challenges associated with rural sewage treatment.
Collapse
Affiliation(s)
- Xu Tan
- China Architecture Design and Research Group, Beijing 100044, PR China; Faculty of Architecture, Civil and Transportation Engineering, Beijing University of Technology, Beijing, 100124, PR China
| | - Li Zhao
- China Architecture Design and Research Group, Beijing 100044, PR China.
| | - Xing Li
- Faculty of Architecture, Civil and Transportation Engineering, Beijing University of Technology, Beijing, 100124, PR China
| | - Yong-Wang Liu
- China Architecture Design and Research Group, Beijing 100044, PR China.
| | - Tian-Shu Lin
- Faculty of Architecture, Civil and Transportation Engineering, Beijing University of Technology, Beijing, 100124, PR China
| | - Yan-Lin Wang
- Faculty of Architecture, Civil and Transportation Engineering, Beijing University of Technology, Beijing, 100124, PR China
| |
Collapse
|
3
|
Shi Q, Yuan Y, Zhou Y, Yuan Y, Liu L, Liu X, Li F, Leng C, Wang H. Pharmaceutical and personal care products (PPCPs) degradation and microbial characteristics of low-temperature operation combined with constructed wetlands. CHEMOSPHERE 2023; 341:140039. [PMID: 37660803 DOI: 10.1016/j.chemosphere.2023.140039] [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: 04/14/2023] [Revised: 08/30/2023] [Accepted: 08/31/2023] [Indexed: 09/05/2023]
Abstract
Emerging contaminants (ECs), which are present in water bodies, could cause global environmental and human health problems. These contaminants originate from various sources such as hospitals, clinics, households, and industries. Additionally, they can also indirectly enter the water supply through runoff from agriculture and leachate from landfills. ECs, specifically Pharmaceutical and personal care products (PPCPs), are causing widespread concern due to their contribution to persistent water pollution. Traditional approaches often involve expensive chemicals and energy or result in the creation of by-products. This study developed a practical and environmentally-friendly method for removing PPCPs, which involved combining and integrating various techniques. To implement this method, it was necessary to establish and used a field simulator based on the real-life scenario. Based on the data analysis, the average removal rates of COD, TP, TN, and NH4+-N were 57%, 59%, 63%, and 73%, respectively. the removal rate of PPCPs by CCWs was found to be 82.7% after comparing samples that were not treated by constructed wetlands and those that were treated. Combined constructed wetlands (CCWs) were found to effectively remove PPCPs from water. This is due to the combined action of plant absorption, absorption, and biodegradation by microorganisms living in the wetlands. Interestingly, the wetland plant reed had been shown to play an important role in removing these pollutants. Microbial degradation was the most important pathway for PPCPs removal in CCWs. Carbamazepine was selected as a typical PPCP for analysis. In addition, the microbial community structure of the composite filler was also investigated. High-throughput sequencing confirmed that the dominant bacteria had good adaptability to PPCPs. This technique not only reduced the potential environmental impact but also served as a foundation for further research on the use of constructed wetlands for the treatment of PPCPs contaminated water bodies and its large-scale implementation.
Collapse
Affiliation(s)
- Qiushi Shi
- Key Laboratory of Bioelectrochemical Water Pollution Control Technology in Tangshan City, North China University of Science and Technology, Tangshan, PR China; College of Civil and Architectural Engineering, North China University of Science and Technology, Tangshan, PR China
| | - Yonggang Yuan
- Key Laboratory of Bioelectrochemical Water Pollution Control Technology in Tangshan City, North China University of Science and Technology, Tangshan, PR China; College of Civil and Architectural Engineering, North China University of Science and Technology, Tangshan, PR China
| | - Yunlong Zhou
- Key Laboratory of Bioelectrochemical Water Pollution Control Technology in Tangshan City, North China University of Science and Technology, Tangshan, PR China; College of Civil and Architectural Engineering, North China University of Science and Technology, Tangshan, PR China
| | - Yue Yuan
- Key Laboratory of Bioelectrochemical Water Pollution Control Technology in Tangshan City, North China University of Science and Technology, Tangshan, PR China; College of Civil and Architectural Engineering, North China University of Science and Technology, Tangshan, PR China
| | - Lin Liu
- Key Laboratory of Bioelectrochemical Water Pollution Control Technology in Tangshan City, North China University of Science and Technology, Tangshan, PR China; College of Civil and Architectural Engineering, North China University of Science and Technology, Tangshan, PR China
| | - Xuejing Liu
- Hebei Mining Area Ecological Restoration Industry Technology Research Institute, Tangshan, 063000, PR China; College of Mining Engineering, North China University of Science and Technology, Tangshan, PR China
| | - Fuping Li
- Hebei Mining Area Ecological Restoration Industry Technology Research Institute, Tangshan, 063000, PR China; College of Mining Engineering, North China University of Science and Technology, Tangshan, PR China
| | - Chunpeng Leng
- Hebei Mining Area Ecological Restoration Industry Technology Research Institute, Tangshan, 063000, PR China; College of Mining Engineering, North China University of Science and Technology, Tangshan, PR China.
| | - Hao Wang
- Key Laboratory of Bioelectrochemical Water Pollution Control Technology in Tangshan City, North China University of Science and Technology, Tangshan, PR China; College of Civil and Architectural Engineering, North China University of Science and Technology, Tangshan, PR China; Hebei Mining Area Ecological Restoration Industry Technology Research Institute, Tangshan, 063000, PR China; College of Mining Engineering, North China University of Science and Technology, Tangshan, PR China.
| |
Collapse
|
4
|
Tanikawa D, Motokawa D, Itoiri Y, Kimura ZI, Ito M, Nagano A. Biogas purification and ammonia load reduction in sewage treatment by two-stage down-flow hanging sponge reactor. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 851:158355. [PMID: 36041617 DOI: 10.1016/j.scitotenv.2022.158355] [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: 03/15/2022] [Revised: 08/13/2022] [Accepted: 08/24/2022] [Indexed: 06/15/2023]
Abstract
In this study, a two-stage down-flow hanging sponge (TSDHS) reactor was used as biotrickling filter for biogas desulfurization by utilizing the anaerobic digester supernatant (ADS) of sewage sludge of an activated sludge process (ASP). The reactor comprises a closed-type first-stage down-flow hanging sponge (1st DHS) and an open-type second-stage down-flow hanging sponge (2nd DHS) reactors. In the 1st DHS, hydrogen sulfide in biogas was dissolved into the ADS, and then it was oxidized into elemental sulfur and sulfate by microbe using dissolved oxygen and nitrite in the ADS. More than 99.9 % of hydrogen sulfide was removed within 400 s of empty bed residence time, and >50 % of removed hydrogen sulfide was oxidized into elemental sulfur and accumulated at the surface of the sponge carrier in the 1st DHS. The 1st DHS effluent was fed into the 2nd DHS for nitrogen removal via nitrification and sulfur-based denitrification with the recirculation of the 2nd DHS effluent under nonaeration condition. In the 2nd DHS, 36.8 % of ammonia and 5.3 % of total inorganic nitrogen were removed. Sulfurimonas and Halothiobacillus were increased and contributed to the sulfur-based denitrification as well as the accumulation of elemental sulfur in the 1st DHS, respectively. In the 2nd DHS, Nitrosococcus, Nitrobacter, and Sulfuritalea were considered as the contributors of nitrogen removal via nitrification and sulfur-based denitrification. Further, this study shows that a TSDHS reactor can achieve not only desulfurization of biogas in the 1st DHS but also a 3.5 %-15 % reduction of the ammonia load in the 2nd DHS by effective utilization of the ADS during sewage treatment, assuming that the ADS is returned to the ASP.
Collapse
Affiliation(s)
- Daisuke Tanikawa
- Department of Civil and Environmental Engineering, National Institute of Technology (KOSEN), Kure College, P.C. 7378506 Kure, Japan.
| | - Daisuke Motokawa
- Advanced Course, Project Design Engineering, National Institute of Technology (KOSEN), Kure College, P.C. 7378506 Kure, Japan
| | - Yuya Itoiri
- Advanced Course, Project Design Engineering, National Institute of Technology (KOSEN), Kure College, P.C. 7378506 Kure, Japan
| | - Zen-Ichiro Kimura
- Department of Civil and Environmental Engineering, National Institute of Technology (KOSEN), Kure College, P.C. 7378506 Kure, Japan
| | - Masahiro Ito
- Technical Research & Development Center, Sanki Engineering Co., Ltd., P.C. 2420007 Yamato, Japan
| | - Akihiro Nagano
- Technical Research & Development Center, Sanki Engineering Co., Ltd., P.C. 2420007 Yamato, Japan
| |
Collapse
|
5
|
Sánchez M, Ramos DR, Fernández MI, Aguilar S, Ruiz I, Canle M, Soto M. Removal of emerging pollutants by a 3-step system: Hybrid digester, vertical flow constructed wetland and photodegradation post-treatments. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 842:156750. [PMID: 35750172 DOI: 10.1016/j.scitotenv.2022.156750] [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: 03/23/2022] [Revised: 05/17/2022] [Accepted: 06/13/2022] [Indexed: 06/15/2023]
Abstract
The removal of emerging pollutants from municipal wastewater was studied for the first time using a three-step pilot-scale system: 1) hybrid digester (HD) as first step, 2) subsurface vertical flow constructed wetland (VF) as second step, and 3) photodegradation (PD) unit as third step or post-treatment. The HD and VF units were built and operated in series with effluent recirculation at pilot scale. For the PD post-treatment, three alternatives were studied at lab-scale, i) UVC irradiation at 254 nm (0.5 h exposure time), ii) UVA irradiation at 365 nm using a TiO2-based photocatalyst and iii) sunlight irradiation using a TiO2-based photocatalyst, the last two for 1 and 2 h. Alternative iii) was also tested at pilot-scale. Degradation of nine compounds was evaluated: acetaminophen (ACE), caffeine (CAF), carbamazepine (CBZ), ketoprofen (KET), ibuprofen (IBU), diclofenac (DCL), clofibric acid (ACB), bisphenol A (BPA), and sotalol (SOT). Overall, the HD-VF-UVC system completely removed (>99.5 %) ACE, CAF, KET, IBU, DCL and ACB, and to a lesser extent SOT (98 %), BPA (83 %) and CBZ (51 %). On the other hand, the HD-VF-UVA/TiO2 system (at 2 h) achieved >99.5 % removal of ACE, CAF, KET, IBU and DCL while ACB, BPA, CBZ and SOT were degraded by 83 %, 81 %, 78 % and 68 %, respectively. Working also at 2 h of exposure time, in summer conditions, the HD-VF-Sol/TiO2 system achieved >99.5 % removal of ACE, CAF, KET, IBU, DCL and ACB, and to a minor extent BPA (80 %), SOT (74 %) and CBZ (69 %). Similar results, although slightly lower for SOT (60 %) and CBZ (59 %), were obtained in the pilot sunlight plus TiO2 catalyst unit. However, the use of sunlight irradiation with a TiO2-based photocatalyst clearly showed lower removal efficiency in autumn conditions (i.e., 47 % SOT, 31 % CBZ).
Collapse
Affiliation(s)
- M Sánchez
- Dept. of Chemistry, Faculty of Sciences & CICA, University of A Coruña, E-15071 A Coruña, Galiza, Spain
| | - D R Ramos
- Dept. of Chemistry, Faculty of Sciences & CICA, University of A Coruña, E-15071 A Coruña, Galiza, Spain
| | - M I Fernández
- Dept. of Chemistry, Faculty of Sciences & CICA, University of A Coruña, E-15071 A Coruña, Galiza, Spain
| | - S Aguilar
- Dept. of Chemistry, Faculty of Sciences & CICA, University of A Coruña, E-15071 A Coruña, Galiza, Spain; Facultad de Ciencias Exactas y Naturales, Universidad Técnica Particular de Loja, Loja, Ecuador
| | - I Ruiz
- Dept. of Chemistry, Faculty of Sciences & CICA, University of A Coruña, E-15071 A Coruña, Galiza, Spain
| | - M Canle
- Dept. of Chemistry, Faculty of Sciences & CICA, University of A Coruña, E-15071 A Coruña, Galiza, Spain
| | - M Soto
- Dept. of Chemistry, Faculty of Sciences & CICA, University of A Coruña, E-15071 A Coruña, Galiza, Spain.
| |
Collapse
|
6
|
Xiong C, Li Q, Tam NF, Zhang X, Tai Y, Wu R, Huang L, Vymazal J, Dai Y, Yang Y. The combination sequence effect on nitrogen removal pathway in hybrid constructed wetlands treating raw sewage from multiple perspectives. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 833:155200. [PMID: 35421456 DOI: 10.1016/j.scitotenv.2022.155200] [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: 01/23/2022] [Revised: 04/06/2022] [Accepted: 04/08/2022] [Indexed: 06/14/2023]
Abstract
The combination sequence of traditional hybrid constructed wetlands (HCWs) affects the removal of nitrogen in raw sewage, but the effect of the combination sequence on nitrogen removal pathway have seldom been reported, especially the specific conditions allowing anammox to occur. Three-stage HCWs, namely vertical flow (VF), horizontal flow (HF) and surface flow (SF) constructed wetlands, were arranged in six different sequences to investigate nitrogen removal efficiencies and microbial removal pathways using metagenomic and stable isotope analyses. Results showed that the combination sequence significantly affected nitrogen removal pathways in HCWs. We found the best removal of total nitrogen (~50%) and ammonium (NH4+-N, ~99%) in HCWs with a VFCW in the 1st stage. Metagenomic results and stable isotope analyses further indicated that simultaneous nitrification and heterotrophic denitrification were the main pathways in unsaturated VFCW, which depended on the energy substance and electron donor supplied by chemical oxygen demand (CODCr) in raw sewage. Nitrifier, anammox bacteria and autotrophic denitrifies prevailed in the subsequent saturated CWs, which tend to nitrogen loss by partial nitrification and anammox in HFCW when fed with NH4+-N wastewater with low CODCr. Providing NH4+-N and oxygen in low CODCr wastewater was the essential step to facilitate anammox process in HFCW. It implied that the problem of poor nitrogen removal due to carbon limitation could be overcome by optimizing conditions in anammox's favor.
Collapse
Affiliation(s)
- Chunhui Xiong
- Department of Ecology, Jinan University, Guangzhou 510632, China
| | - Qiwen Li
- Department of Ecology, Jinan University, Guangzhou 510632, China
| | - Nora Fungyee Tam
- Department of Science, Open University of Hong Kong, Homantin, Kowloon, Hong Kong Special Administrative Region, China; Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region, China
| | - Xiaomeng Zhang
- Department of Ecology, Jinan University, Guangzhou 510632, China
| | - Yiping Tai
- Department of Ecology, Jinan University, Guangzhou 510632, China
| | - Ruitai Wu
- Department of Ecology, Jinan University, Guangzhou 510632, China
| | - Lingjie Huang
- Department of Ecology, Jinan University, Guangzhou 510632, China
| | - Jan Vymazal
- Department of Applied Ecology, Faculty of Environmental Sciences, Czech University of Life Sciences, Prague, 16521 Prague 6, Czech Republic
| | - Yunv Dai
- Department of Ecology, Jinan University, Guangzhou 510632, China.
| | - Yang Yang
- Department of Ecology, Jinan University, Guangzhou 510632, China; Engineering Research Center of Tropical and Subtropical Aquatic Ecological Engineering, Ministry of Education, Guangzhou, China.
| |
Collapse
|
7
|
Xu Y, Li H, Li Y, Zheng X, Zhang C, Gao Y, Chen P, Li Q, Tan L. Systematically assess the advancing and limiting factors of using the multi-soil-layering system for treating rural sewage in China: From the economic, social, and environmental perspectives. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 312:114912. [PMID: 35306420 DOI: 10.1016/j.jenvman.2022.114912] [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: 01/16/2022] [Revised: 03/10/2022] [Accepted: 03/14/2022] [Indexed: 06/14/2023]
Abstract
Solving the problem of rural sewage is considered an essential task in China's rural revitalization strategy. Based on the yearbook data of sewage treatment in rural areas between 2014 and 2019, although the rate of sewage treatment in rural areas of China showed an upward trend, it was still below 35%, mainly due to the lack of suitable sewage treatment technologies. Here, we discuss the multi-soil-layering (MSL) system, which is an emerging technology suitable for rural sewage treatment. It was deemed to overcome the shortcomings of current biological and ecological treatment technologies, such as complex operation, large area, and high operating costs. We used system dynamics to evaluate the advancing and limiting factors of MSL application for rural sewage treatment from the social, environmental, and economic dimensions. The results illustrated a complete causal loop diagram in which essential variables and relationships were concentrated in the technology, operation and maintenance, and satisfaction of farmers. The efficiency of MSL is the key variable affecting the final decision of the MSL application. Overall, using MSL to treat rural sewage could be an option to improve the rural environment in China. However, the scientific technological model for MSL should be further explored. This review provides guidance on how to promote MSL systems in rural areas.
Collapse
Affiliation(s)
- Yan Xu
- Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, China
| | - Houyu Li
- Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, China
| | - Ye Li
- Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, China
| | - Xiangqun Zheng
- Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, China.
| | - Chunxue Zhang
- Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, China
| | - Yi Gao
- Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, China
| | - Peizhen Chen
- Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, China
| | - Qian Li
- Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, China
| | - Lu Tan
- Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, China.
| |
Collapse
|
8
|
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.
Collapse
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.
| |
Collapse
|
9
|
Carballeira T, Ruiz I, Soto M. Improving the performance of vertical flow constructed wetlands by modifying the filtering media structure. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:56852-56864. [PMID: 34080115 DOI: 10.1007/s11356-021-14389-1] [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: 01/29/2021] [Accepted: 05/10/2021] [Indexed: 06/12/2023]
Abstract
The aim of this research was to study the influence of the bed media configuration and particle size on the treatment efficiency of subsurface vertical flow (VF) constructed wetlands (CWs) treating municipal wastewater. Two outdoor pilot units (VF1 and VF2, planted with Phragmites australis) with the configuration C1 were operated in parallel for 2 years at similar surface loading rates of 9.7 ± 3.2 (VF1) and 10.1 ± 3.3 (VF2) g biological oxygen demand (BOD5)/m2·day (19.5 ± 6.4 (VF1) and 20.4 ± 6.2 (VF2) g chemical oxygen demand (COD)/m2·day). A different configuration C2 was used during the third year at 16.9 ± 4.6 (VF1) and 18.2 ± 3.0 (VF2) g BOD5/m2·day and 26.0 ± 7.2 (VF1) and 28.0 ± 4.7 (VF2) g COD/m2·day. Two different filtering materials (1-3-mm sand for VF1 and 2-6-mm fine gravel for VF2) were used for configuration C1. The same units were modified after 2 years of operation by adding a 10-cm layer of fine sand (0-2 mm) on the top (configuration C2). In C1 conditions, the unit with the coarse material VF2 showed significantly (p < 0.05) lower removal efficiencies of total suspended solids (TSS) and BOD5 than VF1, and both units failed to meet the BOD5 discharge limit. In C2 conditions, removal efficiencies reached 82% TSS, 97% BOD5, 76-81% ammonia, and 60-66% TN, without significant differences between VF1 and VF2 units. Removal efficiencies were significantly higher for configuration C2 than that for C1, due to the positive effect of the upper fine sand layer. The presence of this fine sand layer doubled the water retention time and increased the removal rates, while the infiltration rates were high enough for an operation free of clogging.
Collapse
Affiliation(s)
- Tania Carballeira
- Department of Chemistry, University of A Coruña, Rúa da Fraga 10, 15008, A Coruña, Galiza, Spain
| | - Isabel Ruiz
- Department of Chemistry, University of A Coruña, Rúa da Fraga 10, 15008, A Coruña, Galiza, Spain
| | - Manuel Soto
- Department of Chemistry, University of A Coruña, Rúa da Fraga 10, 15008, A Coruña, Galiza, Spain.
| |
Collapse
|
10
|
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.
Collapse
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
| |
Collapse
|
11
|
Nguyen XC, Ly QV, Peng W, Nguyen VH, Nguyen DD, Tran QB, Huyen Nguyen TT, Sonne C, Lam SS, Ngo HH, Goethals P, Le QV. Vertical flow constructed wetlands using expanded clay and biochar for wastewater remediation: A comparative study and prediction of effluents using machine learning. JOURNAL OF HAZARDOUS MATERIALS 2021; 413:125426. [PMID: 33621772 DOI: 10.1016/j.jhazmat.2021.125426] [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: 11/16/2020] [Revised: 01/24/2021] [Accepted: 02/11/2021] [Indexed: 06/12/2023]
Abstract
This study evaluated and compared the performance of two vertical flow constructed wetlands (VF) using expanded clay (VF1) and biochar (VF2), of which both are low-cost, eco-friendly, and exhibit potentially high adsorption as compared to conventional filter layers. Both VFs achieved relatively high removal for organic matters (i.e. Biological oxygen demand during 5 days, BOD5) and nitrogen, accounting for 9.5 - 10.5 g.BOD5.m-2.d-1 and 3.5 - 3.6 g.NH4-N.m-2.d-1, respectively. The different filter materials did not exert any significant discrepancy to effluent quality in terms of suspended solids, organic matters and NO3-N (P > 0.05), but they did influence NH4-N effluent as evidenced by the removal rate of that by VF1 and VF2 being of 82.4 ± 5.7 and 84.6 ± 6.4%, respectively (P < 0.05). The results obtained from the designed systems were further subject to machine learning to clarify the effecting factors and predict the effluents. The optimal algorithms were random forest, generalized linear model, and support vector machine. The values of the coefficient of determination (R2) and the root mean square error (RMSE) of whole fitting data achieved 74.0% and 5.0 mg.L-1, 80.0% and 0.3 mg.L-1, 90.1% and 2.9 mg.L-1, and 48.5% and 0.5 mg.L-1 for BOD5_VF1, NH4-N_VF1, BOD5_VF2, and NH4-N_VF2, respectively.
Collapse
Affiliation(s)
- Xuan Cuong Nguyen
- Laboratory of Energy and Environmental Science, Institute of Research and Development, Duy Tan University, Da Nang 550000, Vietnam; Faculty of Environmental and Chemical Engineering, Duy Tan University, Da Nang 550000, Vietnam
| | - Quang Viet Ly
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, China
| | - Wanxi Peng
- Henan Province Engineering Research Center for Biomass Value-added Products, School of Forestry, Henan Agricultural University, Zhengzhou 450002, China
| | - Van-Huy Nguyen
- Department for Management of Science and Technology Development, Ton Duc Thang University, Ho Chi Minh City, Vietnam; Faculty of Applied Sciences, Ton Duc Thang University, Ho Chi Minh City, Vietnam.
| | - Dinh Duc Nguyen
- Faculty of Environmental and Food Engineering, Nguyen Tat Thanh University, 300A Nguyen Tat Thanh, District 4, Ho Chi Minh City 755414, Vietnam; Department of Environmental Energy Engineering, Kyonggi University, Suwon 16227, Republic of Korea
| | - Quoc Ba Tran
- Laboratory of Energy and Environmental Science, Institute of Research and Development, Duy Tan University, Da Nang 550000, Vietnam; Faculty of Environmental and Chemical Engineering, Duy Tan University, Da Nang 550000, Vietnam
| | - Thi Thanh Huyen Nguyen
- Laboratory of Energy and Environmental Science, Institute of Research and Development, Duy Tan University, Da Nang 550000, Vietnam; Faculty of Environmental and Chemical Engineering, Duy Tan University, Da Nang 550000, Vietnam
| | - Christian Sonne
- Aarhus University, Department of Bioscience, Arctic Research Centre (ARC), Frederiksborgvej 399, PO Box 358, DK-4000 Roskilde, Denmark
| | - Su Shiung Lam
- Higher Institution Centre of Excellence (HICoE), Institute of Tropical Aquaculture and Fisheries (AKUATROP), Universiti Malaysia Terengganu, 21030 Kuala Nerus, Terengganu, Malaysia
| | - Huu Hao Ngo
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NWS 2007, Australia
| | - Peter Goethals
- Laboratory of Environmental Toxicology and Aquatic Ecology, Ghent University, Jozef Plateaustraat 22, B-9000 Ghent, Belgium
| | - Quyet Van Le
- Laboratory of Energy and Environmental Science, Institute of Research and Development, Duy Tan University, Da Nang 550000, Vietnam.
| |
Collapse
|
12
|
Cheng J, Zhang X, Tang Y, Song Z, Jiang Y, Xu Z, Jin X. Nitrogen removal from domestic wastewater using core-shell anthracite/Mg-layered double hydroxides (LDHs) in constructed wetlands. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:38349-38360. [PMID: 33733402 DOI: 10.1007/s11356-021-13422-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 03/09/2021] [Indexed: 06/12/2023]
Abstract
To investigate the mechanism of nitrogen removal by anthracites and enhance the nitrogen removal efficiency in constructed wetland, three kinds of layered double hydroxides (MgFe-LDHs, MgCo-LDHs, MgAl-LDHs) were prepared by co-precipitation under alkaline conditions and coated in situ on the surface of anthracites to synthesize core-shell anthracites/Mg-LDHs composites. Experiments with different treatments (columns loaded with original anthracites and anthracite/Mg-LDH composites) were conducted to study the nitrogen removal efficiency of domestic wastewater in constructed wetlands. The results of nitrogen removal experiments showed that the anthracite/MgAl-LDH composite had the best performance with average removal rates of 53.69%, 72.91%, and 47.43% for TN, NH4+-N, and organic nitrogen, respectively. Modification changed the denitrification mode of the anthracites. The data of adsorption isothermal experiments were fitted better with the Freundlich model. The amount of ammonifier, nitrosobacteria, nitrobacter, and denitrifier on the surface of the Mg-LDH-modified anthracite was higher than that of the original anthracite. The performance of the anthracite in removing nitrogen was attributed to physical interception, chemical adsorption, and biological degradation. Moreover, the modified anthracites were superior to the original anthracite in the chemical adsorption and biodegradation, which indicated that coating the Mg-LDHs on the surface of common anthracite was a potential method to improve the nitrogen removal efficiency of domestic wastewater and to restore the eutrophic water body.
Collapse
Affiliation(s)
- Jing Cheng
- School of Civil Engineering and Architecture, Wuhan University of Technology, 122, Luoshi Road, Hongshan District, Wuhan, 430070, China
| | - Xiangling Zhang
- School of Civil Engineering and Architecture, Wuhan University of Technology, 122, Luoshi Road, Hongshan District, Wuhan, 430070, China.
| | - Yuqi Tang
- School of Civil Engineering and Architecture, Wuhan University of Technology, 122, Luoshi Road, Hongshan District, Wuhan, 430070, China
| | - Zan Song
- School of Civil Engineering and Architecture, Wuhan University of Technology, 122, Luoshi Road, Hongshan District, Wuhan, 430070, China
| | - Yinghe Jiang
- School of Civil Engineering and Architecture, Wuhan University of Technology, 122, Luoshi Road, Hongshan District, Wuhan, 430070, China
| | - Zhouying Xu
- School of Civil Engineering and Architecture, Wuhan University of Technology, 122, Luoshi Road, Hongshan District, Wuhan, 430070, China
| | - Xi Jin
- School of Civil Engineering and Architecture, Wuhan University of Technology, 122, Luoshi Road, Hongshan District, Wuhan, 430070, China
| |
Collapse
|
13
|
Lai C, Sun Y, Guo Y, Cai Q, Yang P. A novel integrated bio-reactor of moving bed and constructed wetland (MBCW) for domestic wastewater treatment and its microbial community diversity. ENVIRONMENTAL TECHNOLOGY 2021; 42:2653-2668. [PMID: 31902307 DOI: 10.1080/09593330.2019.1709904] [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: 08/23/2019] [Accepted: 12/22/2019] [Indexed: 06/10/2023]
Abstract
An MBBR and CW combo bio-reactor (MBCW) was designed as a novel hybrid process for simultaneous organic, nitrogen and phosphate removal through the long-term operation. The effect of the internal recycling rate (IRR), hydraulic retention time (HRT) and chemical oxygen demand/total nitrogen (C/N) ratio were all discussed, and the recommended values were 5:1, 12 h and >6, respectively. A higher C/N ratio was a key factor for achieving a higher TN removal. The mixed biocarrier system was realized by inoculating porous polymer carriers (PPC) and cylindrical polyethylene carriers (CPC) and achieving a higher organic biodegradation and nitrification rate compared to a single carrier system. Microorganism activities and plants' uptake or utilization both contributed to the nutrient removal in a constructed wetland. High-throughput sequencing results revealed an abundant microbial diversity and a distinct microbial distribution in the whole system where Flavobacterium (14.2%), Acinetobacter (12.87%) and Rhodobacter (10.83%) dominated on PPC, Terrimonas (8.88%), Reyranella (6.61%) and Rubinisphaera (5.63%) dominated on CPC, Comamonas (4.18%), Gemmobacter (4.02%) and Hydrogenophaga (3.97%) dominated on CWs, as well as Citrobacter (53.13%) on suspended floc.
Collapse
Affiliation(s)
- Changmiao Lai
- College of Architecture and Environment, Sichuan University, Chengdu, People's Republic of China
| | - Yu Sun
- College of Architecture and Environment, Sichuan University, Chengdu, People's Republic of China
| | - Yong Guo
- School of Chemical Engineering, Sichuan University, Chengdu, People's Republic of China
| | - Qin Cai
- College of Architecture and Environment, Sichuan University, Chengdu, People's Republic of China
| | - Ping Yang
- College of Architecture and Environment, Sichuan University, Chengdu, People's Republic of China
| |
Collapse
|
14
|
The Potential Role of Hybrid Constructed Wetlands Treating University Wastewater—Experience from Northern Italy. SUSTAINABILITY 2020. [DOI: 10.3390/su122410604] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
University wastewater is a type of wastewater with higher pollutants load and flow rate variability than typical domestic wastewater. Constructed wetlands (CW) could be used for university wastewater treatment and consequently for wastewater reuse. A hybrid CW pilot plant, at the University of Bologna (Italy), was monitored to assess its potential to be used at the university. Its treatment performance was monitored for one year and public acceptance explored through a survey. The pilot plant had two treatment lines, (1) a vertical flow CW (VFCW) and a planted horizontal flow CW (HFCW), and (2) the same VFCW and an unplanted horizontal flow filter (HFF). The HFCW achieved higher removals than the HFF, but it was also found to be prone to higher water losses. However, both treatment lines met the Italian limits for discharge in natural water bodies and some of the limits for wastewater reuse in Italy and the EU. The VFCW alone was not able to meet the same limits, demonstrating the advantages of hybrid over single stage CWs. A positive attitude towards CWs and wastewater reuse was found among the survey participants. Therefore, hybrid CWs (planted and unplanted) are considered a feasible technology for application at universities.
Collapse
|
15
|
Gonzalo OG, Ruiz I, Soto M. Effect of different bypass rates and unit area ratio in hybrid constructed wetlands. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:40355-40369. [PMID: 32666454 DOI: 10.1007/s11356-020-09982-9] [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: 03/19/2020] [Accepted: 07/01/2020] [Indexed: 06/11/2023]
Abstract
This study presents the performance of a hybrid constructed wetland (Bp(VF + HF)2:1) system which consists of an unsaturated vertical flow (VF) unit followed by a saturated down-flow unit simulating horizontal flow (HF) with HF/VF area ratio of 0.5 and influent bypass to the HF unit. Treating synthetic wastewater simulating municipal wastewater, optimum total nitrogen (TN) removal (57%) was reached at 39% bypass and surface loading rate (SLR) of 33 g BOD5/m2 day and 9.7 g TN/m2 day (overall system). On the other hand, treating actual municipal wastewater, the system reached 63% TN removal at 30% bypass and SLR of 18 g BOD5/m2 day and 4.7 g TN/m2 day. Surface removal rates reached 5.5 and 3.0 g TN/m2 day for synthetic and municipal wastewater. Surface nitrification rate in the VF unit was in the range of 5.0-7.4 and 3.6-3.8 g N/m2 day for synthetic and municipal wastewater, respectively, indicating a large effect of wastewater characteristics on the nitrification process. Infiltration rate in the VF unit remained high and far from clogging risk. Overall greenhouse gas emissions were 0.11 (N2O) and 0.41 (CH4) g/m2 day which corresponded to emissions factors (relative to total organic carbon and TN influent) of 0.7% (N2O) and 3.6% (CH4). Compared with a similar system with a different HF/VF area ratio of 2.0, organic matter and nitrogen removal efficiency was similar, but surface removal rates were about 3 times higher.
Collapse
Affiliation(s)
- Omar Gael Gonzalo
- Department of Chemistry, University of A Coruña, Rúa da Fraga 10, 15008, A Coruña, Galiza, Spain
| | - Isabel Ruiz
- Department of Chemistry, University of A Coruña, Rúa da Fraga 10, 15008, A Coruña, Galiza, Spain
| | - Manuel Soto
- Department of Chemistry, University of A Coruña, Rúa da Fraga 10, 15008, A Coruña, Galiza, Spain.
| |
Collapse
|
16
|
Moreira FD, Dias EHO. Constructed wetlands applied in rural sanitation: A review. ENVIRONMENTAL RESEARCH 2020; 190:110016. [PMID: 32768473 DOI: 10.1016/j.envres.2020.110016] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Accepted: 07/25/2020] [Indexed: 06/11/2023]
Abstract
This systematic literature review aimed at presenting experiences on the use of constructed wetlands (CW) as an alternative for the treatment of domestic wastewater in rural areas worldwide. CW units are often preceded by a pre-treatment step, although systems comprising arrangements of CW with different flow types are also applied. The literature review showed that the most commonly treatment system used in rural areas comprised septic tanks followed by CW. Overall, CW rural sanitation systems have shown to consistently remove pollutants, with median removal efficiencies equal to 87% for TSS, 89% for COD, 93% for BOD, 70% for Ntotal and 72% for Ptotal. Removal rates of indicator bacteria of up to 4.0 log10 have also been reported. Recent studies have shown CW to be efficient at removing hormones, pharmaceutical compounds and toxicity of wastewater. Consequently, final effluents are often in compliance with effluent discharge and wastewater reuse regulations. The adoption of pre-treatment reduces CW area requirements and clogging issues, and planted CW present benefits in terms of the removal of pollutants including pathogens. Low implementation and operational costs, simplified operation and maintenance, and high-quality final effluents favour CW. Guidelines provided by the local, competent authorities may support the rural application of CW. Finally, CW systems comprise a promising, sustainable solution for rural sanitation which may support access to adequate and equitable sanitation to several people as well as safe wastewater recycling and reuse, as encouraged by UN Sustainable Development Goal 6, Targets 3 and 4.
Collapse
Affiliation(s)
- Fernanda Deister Moreira
- Department of Sanitary and Environmental Engineering (DESA), School of Engineering, Federal University of Minas Gerais (UFMG). Av. Antônio Carlos, 6627, Escola de Engenharia, Bloco 1, 4° andar. Pampulha, Belo Horizonte - MG, CEP 31270-010, Brazil.
| | - Edgard Henrique Oliveira Dias
- Department of Sanitary and Environmental Engineering (ESA), Faculty of Engineering, Federal University of Juiz de Fora (UFJF). Rua José Lourenço Kelmer, s/n, Campus UFJF. São Pedro, Juiz de Fora - MG, CEP 36036-900, Brazil.
| |
Collapse
|
17
|
Yuan Y, Yang B, Wang H, Lai X, Li F, Salam MMA, Pan F, Zhao Y. The simultaneous antibiotics and nitrogen removal in vertical flow constructed wetlands: Effects of substrates and responses of microbial functions. BIORESOURCE TECHNOLOGY 2020; 310:123419. [PMID: 32361200 DOI: 10.1016/j.biortech.2020.123419] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 04/16/2020] [Accepted: 04/19/2020] [Indexed: 06/11/2023]
Abstract
A vertical flow constructed wetland (VFCW) packed with the different substrates was designed to remediate the antibiotics in the wastewater. Zeolite (CW-Z) paralleled with Manganese (Mn) ore (CW-M) and biochar (CW-C) were used to enhance the synchronous removal of ciprofloxacin hydrochloride (CIPH), sulfamethazine (SMZ) and nitrogen (N) from the wastewater. The result indicated that CW-M had a significant potential to remove CIPH (93%), SMZ (69%), TN (71%), NH4+-N (94%) and NO3--N (94%) across all the treatments. The abundance of amoA, nirK and nirS genes are dramatically higher in CW-M and CW-C, while CW-C inhibited the production of quinolone resistance genes. Results showed that different substrates could affect the microbial diversity and structure. The addition of Mn ore to the water led to an improved abundance of nitrogen-related phyla. Overall, Mn ore has a considerable potential to simultaneously remove antibiotics and N in VFCWs.
Collapse
Affiliation(s)
- Yingrui Yuan
- 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
| | - Hui Wang
- School of Water Conservancy and Environment, University of Jinan, Jinan 250022, China.
| | - Xiaoshuang Lai
- 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
| | - Mir Md Abdus Salam
- School of Forest Sciences, University of Eastern Finland, Yliopistokatu 7, P.O. Box 111, 80100 Joensuu, Finland
| | - Fuxia Pan
- Jinan Environmental Research Academy, Jinan, Shandong 250102, China
| | - Yuqiang Zhao
- Jinan Environmental Research Academy, Jinan, Shandong 250102, China
| |
Collapse
|
18
|
Lai X, Zhao Y, Pan F, Yang B, Wang H, Wang S, He F. Enhanced optimal removal of nitrogen and organics from intermittently aerated vertical flow constructed wetlands: Relative COD/N ratios and microbial responses. CHEMOSPHERE 2020; 244:125556. [PMID: 32050346 DOI: 10.1016/j.chemosphere.2019.125556] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 11/26/2019] [Accepted: 12/05/2019] [Indexed: 06/10/2023]
Abstract
Carbon source and dissolved oxygen are the critical factors which sustain the stable redox environment for the microbes to implement the removal of nitrogen and organics in vertical flow constructed wetlands (VFCWs). The effect mechanisms of the COD/N ratios in intermittently aerated VFCWs are needed to be investigated in order to increase the synchronous removal efficiency of pollutants. In this study, the combined effects of COD/N ratios (3, 6, 12) and intermittent aeration in VFCWs on pollutant removal, microbial communities and related function genes were studied. The results showed the increase of COD/N ratios from 3 to 12 enhanced the removal efficiency of TN, NO3--N and COD. The removals of NH4+-N decreased as the COD/N ratio increased. The optimal removals of TN (87.65%), NH4+-N (93.20%), NO3--N (80.80%) and COD (73.93%) were obtained in VFCW2 (COD/N ratios was 6). Illumina Miseq High-throughput sequencing analysis showed that high COD/N ratios increased the richness and diversity of microbial communities. The absolute abundance of nirK, nosZ, nirS, amoA, nxrA, and anammox bacterial 16S rRNA presented various changes under the different ratios of COD/N. The increase of COD/N ratios enhanced the copy numbers of nirS, nirK and nosZ, which participate in denitrification process. High COD/N ratios (6 and 12) were in favor of Actinobacteria, Firmicutes and Chloroflexi, which mainly play important roles in the process of denitrification. This paper implies that the combination of carbon source and aeration is necessary to sustain high microbial activities during pollutant removal in VFCWs.
Collapse
Affiliation(s)
- Xiaoshuang Lai
- School of Water Conservancy and Environment, University of Jinan, Jinan, 250022, China
| | - Yuqiang Zhao
- Jinan Environmental Research Academy, Jinan, Shandong, 250102, China
| | - Fuxia Pan
- Jinan Environmental Research Academy, Jinan, Shandong, 250102, China
| | - Baoshan Yang
- School of Water Conservancy and Environment, University of Jinan, Jinan, 250022, China; Key Laboratory of Water Resources and Environmental Engineering in Universities of Shandong Province (University of Jinan), Jinan, 250022, China
| | - Hui Wang
- School of Water Conservancy and Environment, University of Jinan, Jinan, 250022, China; Key Laboratory of Water Resources and Environmental Engineering in Universities of Shandong Province (University of Jinan), Jinan, 250022, China.
| | - Shuzhi Wang
- School of Water Conservancy and Environment, University of Jinan, Jinan, 250022, China
| | - Fei He
- Jinan Environmental Research Academy, Jinan, Shandong, 250102, China
| |
Collapse
|
19
|
Li X, Li Y, Lv D, Li Y, Wu J. Nitrogen and phosphorus removal performance and bacterial communities in a multi-stage surface flow constructed wetland treating rural domestic sewage. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 709:136235. [PMID: 31905548 DOI: 10.1016/j.scitotenv.2019.136235] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 12/18/2019] [Accepted: 12/18/2019] [Indexed: 06/10/2023]
Abstract
A multi-stage surface flow constructed wetland (SFCW) is used to treat decentralized rural domestic sewage. The performance of a multi-stage SFCW located in Hunan, China, and the associated microbial community structures were investigated. The average removal rates of the multi-stage SFCW planted with Myriophyllum elatinoides were 1.0 g m-2 d-1, 0.84 g m-2 d-1, 61.3 mg m-2 d-1, and 85.3 mg m-2 d-1 for total nitrogen (TN), ammonia (NH4+), nitrate (NO3-), and total phosphorus (TP), respectively. Furthermore, the sediment and presence of plants were found to be important for the removal N and P. The average removal rates by sediment and plants were 196.6 mg N m-2 d-1 and 49.9 mg P m-2 d-1, 17.6 mg N m-2 d-1 and 8.1 mg P m-2 d-1, respectively. The microbial community profiles demonstrated that Proteobacteria, Chloroflexi, Bacteroidetes, Firmicutes and Euryarchaeota were the predominant phyla in each stage and at different sampling times. The concentrations of NO3-, TP, TN, and NH4+, and the pH of the sediment and water had a significant effect on the presence of denitrifying bacteria in the anaerobic environment. Whereas, dissolved oxygen (DO) and redox potential (Eh) had a significant effect on the presence of nitrifying bacteria in the aerobic environment. This research strongly supports that the use of the multi-stage SFCW promotes bacterial diversity and changes bacterial community in the sediment.
Collapse
Affiliation(s)
- Xi Li
- Key Laboratory of Agro-ecological Processes in Subtropical Regions, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Hunan 410125, PR China; Changsha Research Station for Agricultural & Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Hunan 410125, PR China
| | - Yuyuan Li
- Key Laboratory of Agro-ecological Processes in Subtropical Regions, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Hunan 410125, PR China; Changsha Research Station for Agricultural & Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Hunan 410125, PR China.
| | - Dianqing Lv
- School of Resources and Environmental Science, Hunan Normal University, Hunan 410081, PR China
| | - Yong Li
- Key Laboratory of Agro-ecological Processes in Subtropical Regions, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Hunan 410125, PR China; Changsha Research Station for Agricultural & Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Hunan 410125, PR China
| | - Jinshui Wu
- Key Laboratory of Agro-ecological Processes in Subtropical Regions, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Hunan 410125, PR China; Changsha Research Station for Agricultural & Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Hunan 410125, PR China
| |
Collapse
|
20
|
Xiong C, Tam NF, Dai Y, Zhang X, Li R, Zheng Y, Wang L, Yang Y. Enhanced performance of pilot-scale hybrid constructed wetlands with A/O reactor in raw domestic sewage treatment. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2020; 258:110026. [PMID: 31929064 DOI: 10.1016/j.jenvman.2019.110026] [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: 07/19/2019] [Revised: 12/06/2019] [Accepted: 12/21/2019] [Indexed: 06/10/2023]
Abstract
The aim of this study was to improve the nutrient removal efficiency by optimizing aeration time, hydraulic loading rate (HLR) and combination type in hybrid constructed wetlands (HCWs) with anoxic/oxic (A/O) reactor. The results showed that, the highest removal percentages of TN, NH4-N, TP, PO4-P and COD were 87.9%, 98.1%, 86.1%, 85.3% and 95.2%, respectively, in horizontal subsurface flow (HF) - surface flow - vertical subsurface flow CW with A/O reactor at 0.1 m/d HLR and 2 h aeration. HLR, aeration time and combination type had a significant impact on the removal of nutrients, though plant diversity did not have any significant influence. Presence of the A/O reactor improved the removal of TN in the HCWs by reducing influent loading and changing influent characteristics, thereby affecting the role of nitrification, anammox, and denitrification processes. The anammox process was the dominant pathway in the 1st HF CWs during the aeration period, where the highest removal of phosphorus was observed.
Collapse
Affiliation(s)
- Chunhui Xiong
- Department of Ecology, Jinan University, Guangzhou, 510632, China
| | - Nora Fungyee Tam
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
| | - Yunv Dai
- Department of Ecology, Jinan University, Guangzhou, 510632, China.
| | - Xiaomeng Zhang
- Department of Ecology, Jinan University, Guangzhou, 510632, China
| | - Rui Li
- Department of Ecology, Jinan University, Guangzhou, 510632, China
| | - Yu Zheng
- Department of Ecology, Jinan University, Guangzhou, 510632, China
| | - Lin Wang
- Department of Ecology, Jinan University, Guangzhou, 510632, China
| | - Yang Yang
- Department of Ecology, Jinan University, Guangzhou, 510632, China; Engineering Research Center of Tropical and Subtropical Aquatic Ecological Engineering, Ministry of Education, Guangzhou, China.
| |
Collapse
|
21
|
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.
Collapse
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.
| |
Collapse
|
22
|
Song P, Huang G, Hong Y, An C, Xin X, Zhang P. A biophysiological perspective on enhanced nitrate removal from decentralized domestic sewage using gravitational-flow multi-soil-layering systems. CHEMOSPHERE 2020; 240:124868. [PMID: 31542583 DOI: 10.1016/j.chemosphere.2019.124868] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Revised: 09/09/2019] [Accepted: 09/13/2019] [Indexed: 06/10/2023]
Abstract
Multi-soil-layering (MSL) system with brick-wall pattern structure and gravitational flow can be used for decentralized rural domestic sewage treatment. The capability of soil for contaminant removal is maximized within soil mixture blocks (SMBs). However, the performance of removing nitrate was still not ideal during operation. To improve its performance in MSL system, the relationship between biophysiological characteristics of denitrifying species and operating conditions was studied. Microbial species diversity of activated sludge and soil samples were analyzed. The significant effects of independent factors and their interactions on microbial species diversity and denitrifying species abundance were revealed on the basis of factorial analysis. The results indicated activated sludge in SMBs played a key role in increasing the richness of denitrifying species in MSL system. Slow-release poly (butylene succinate) (PBS) had the most dominant positive effect on increasing denitrifying species abundance. Submersion had significantly positive effect on species richness in SMBs. These three factors, including activated sludge, PBS in SMBs, and submersion condition had different significant effects on microbial responses. They were favorable for denitrification and ensuring a better removal efficiency of nitrate and total nitrogen. The porous zeolites were served as the habitats for most of aerobic bacteria to form biofilms, which could promote the oxygen consumption in both sewage and system to improve denitrification in SMBs. The results could help on the enhancement of denitrification in MSL system from biophysiological insights. It can provide a sound strategy for using MSL system with great performance on contaminant removal.
Collapse
Affiliation(s)
- Pei Song
- MOE Key Laboratory of Resources and Environmental Systems Optimization, North China Electric Power University, Beijing, 102206, China
| | - Guohe Huang
- Center for Energy, Environment and Ecology Research, UR-BNU, Beijing Normal University, Beijing, 100875, China.
| | - Yongyuan Hong
- MOE Key Laboratory of Resources and Environmental Systems Optimization, North China Electric Power University, Beijing, 102206, China
| | - Chunjiang An
- Department of Building, Civil and Environmental Engineering, Concordia University, Montreal, Quebec, H3G 1M8, Canada
| | - Xiaying Xin
- Institute for Energy, Environment and Sustainable Communities, University of Regina, Regina, S4S 0A2, Canada
| | - Peng Zhang
- Institute for Energy, Environment and Sustainable Communities, University of Regina, Regina, S4S 0A2, Canada
| |
Collapse
|
23
|
Huang J, Yan C, Liu J, Guan W, Singh RP, Cao C, Xiao J. Feasibility study of vertical flow constructed wetland for tertiary treatment of nanosilver wastewater and temporal-spatial distribution of pollutants and microbial community. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2019; 245:28-36. [PMID: 31136937 DOI: 10.1016/j.jenvman.2019.04.128] [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: 01/04/2019] [Revised: 04/23/2019] [Accepted: 04/30/2019] [Indexed: 06/09/2023]
Abstract
Silver nanoparticles (AgNPs) have the potential to cause negative effects on nutrient removal in constructed wetlands (CWs), further leading to the deterioration of the water. The current work aimed to investigate the feasibility of vertical flow CW (VFCW) for tertiary treatment of AgNPs wastewater, temporal-spatial distribution of pollutants, and microbial community after 450-day exposure. Results reveal that the effluent of VFCW could still meet the discharge limits except the slightly excessive concentration of phosphorus (>0.5 mg/L) from day 390, with the average removal efficiencies of 83%, 61%, 42%, 70%, and 66% for the chemical oxygen demand, total nitrogen, ammonia nitrogen, total phosphorus, and soluble orthophosphate during 450 days, respectively. Results show that AgNPs removal was relatively stable over time, up to 96%. The temporal-spatial analysis reveals that all contaminants were mainly retained in the soil layer. The Ag concentrations in the upper soil layer and plant roots were higher than that in the lower soil layer and plant stems and leaves, respectively. Microbial sequencing analysis reveals the significant differences in the microbial community at different depths on day 450, with the dominant phyla of Proteobacteria, Acidobacteria, Chloroflexi and Bacteroidetes, and dominant genera of Halomonas and Pseudomonas. These results provide much needed knowledge for the implementation of ecological technologies for AgNPs and nutrient removal simultaneously.
Collapse
Affiliation(s)
- Juan Huang
- Dept. of Municipal Engineering, School of Civil Engineering, Southeast University, Nanjing, 210096, China.
| | - Chunni Yan
- Dept. of Municipal Engineering, School of Civil Engineering, Southeast University, Nanjing, 210096, China
| | - Jialiang Liu
- Dept. of Municipal Engineering, School of Civil Engineering, Southeast University, Nanjing, 210096, China
| | - Wenzhu Guan
- Dept. of Municipal Engineering, School of Civil Engineering, Southeast University, Nanjing, 210096, China
| | - Rajendra Prasad Singh
- Dept. of Municipal Engineering, School of Civil Engineering, Southeast University, Nanjing, 210096, China
| | - Chong Cao
- Dept. of Municipal Engineering, School of Civil Engineering, Southeast University, Nanjing, 210096, China
| | - Jun Xiao
- Dept. of Municipal Engineering, School of Civil Engineering, Southeast University, Nanjing, 210096, China
| |
Collapse
|
24
|
Chen J, Deng WJ, Liu YS, Hu LX, He LY, Zhao JL, Wang TT, Ying GG. Fate and removal of antibiotics and antibiotic resistance genes in hybrid constructed wetlands. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 249:894-903. [PMID: 30965541 DOI: 10.1016/j.envpol.2019.03.111] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 02/26/2019] [Accepted: 03/27/2019] [Indexed: 05/12/2023]
Abstract
Hybrid design and artificial aeration has been widely applied in wetlands, but little is known about their effectiveness in the removal of antibiotics and antibiotic resistance genes (ARGs). Here we investigated the performance of various mesocosm-scale constructed wetlands (CWs) with artificial aeration and hybrid design in removal of antibiotics and ARGs from antibiotics-spiked domestic sewage. Four hybrid constructed wetland systems with zeolite as substrate and Iris tectorum Maxim as plant were set up to have different artificial aeration designs. The aqueous removal efficiencies of total antibiotics ranged from 87.4% to 95.3%, while those of total ARGs varied from 87.8% to 99.1%. The mass removal of antibiotics by the CWs was attributed mainly to the microbial degradation. The present study imply that sorption of substrates and biological processes could be the two main mechanisms for ARGs elimination. The results from this study showed the hybrid CWs with artificial aeration could enhance treatment efficiencies of antibiotics and ARGs as well as conventional pollutants.
Collapse
Affiliation(s)
- Jun Chen
- The Environmental Research Institute, MOE Key Laboratory of Environmental Theoretical Chemistry, South China Normal University, Guangzhou, 510006, China
| | - Wen-Jing Deng
- Department of Science and Environmental Studies, The Education University of Hong Kong, Tai Po, N.T., Hong Kong Special Administrative, Region, China
| | - You-Sheng Liu
- The Environmental Research Institute, MOE Key Laboratory of Environmental Theoretical Chemistry, South China Normal University, Guangzhou, 510006, China
| | - Li-Xin Hu
- The Environmental Research Institute, MOE Key Laboratory of Environmental Theoretical Chemistry, South China Normal University, Guangzhou, 510006, China
| | - Liang-Ying He
- The Environmental Research Institute, MOE Key Laboratory of Environmental Theoretical Chemistry, South China Normal University, Guangzhou, 510006, China
| | - Jian-Liang Zhao
- The Environmental Research Institute, MOE Key Laboratory of Environmental Theoretical Chemistry, South China Normal University, Guangzhou, 510006, China
| | - Tuan-Tuan Wang
- The Environmental Research Institute, MOE Key Laboratory of Environmental Theoretical Chemistry, South China Normal University, Guangzhou, 510006, China; State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
| | - Guang-Guo Ying
- The Environmental Research Institute, MOE Key Laboratory of Environmental Theoretical Chemistry, South China Normal University, Guangzhou, 510006, China.
| |
Collapse
|
25
|
Saba B, Khan M, Christy AD, Kjellerup BV. Microbial phyto-power systems – A sustainable integration of phytoremediation and microbial fuel cells. Bioelectrochemistry 2019; 127:1-11. [DOI: 10.1016/j.bioelechem.2018.12.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Revised: 12/14/2018] [Accepted: 12/14/2018] [Indexed: 10/27/2022]
|
26
|
Liu Y, Liu X, Li K, Lu S, Guo X, Zhang J, Xi B. Removal of nitrogen from low pollution water by long-term operation of an integrated vertical-flow constructed wetland: Performance and mechanism. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 652:977-988. [PMID: 30380502 DOI: 10.1016/j.scitotenv.2018.10.313] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2018] [Revised: 10/07/2018] [Accepted: 10/23/2018] [Indexed: 06/08/2023]
Abstract
The efficiency of nitrogen removal and its mechanism, aquatic organism distribution characteristics and regeneration capability of zeolite from an integrated vertical-flow constructed wetland (IVFCW) for low pollution water treatment were evaluated after steady and continuous operation for eight years. After running for eight years, better than average COD and NH4+-N removal were observed in the IVFCW. The NH4+-N removal rate in this system was controlled by ammoxidation and adsorption and ion exchange of zeolite. The low total nitrogen (TN) removal efficiency was due to NO3--N accumulation and zeolite desorption. In addition, this phenomenon indicated that because of poor organic carbon sources, nitrification was stronger than denitrification, consistent with the distribution of the functional genes for nitrification and denitrification. The biological activity in this system was abundant, especially that of spirogyra and navicula. The saturated adsorption capacity of zeolite was as high as 1.35 mg g-1 with a desorption rate of <20%. There were no obvious differences among the effects of aeration, water cleaning, drained reoxygenation and steam stripping for zeolite regeneration (adsorption capacity of >50%). However, the drained reoxygenation performance of was better due to zero energy consumption and regeneration in situ.
Collapse
Affiliation(s)
- Ying Liu
- State Environmental Protection Scientific Observation and Research Station for Lake Dongtinghu (SEPSORSLD), National Engineering Laboratory for Lake Pollution Control and Ecological Restoration, State Key Laboratory of Environmental Criteria an Risk Assessment, Research Centre of Lake Environment, Chinese Research Academy of Environmental Sciences, Beijing 100012, People's Republic of China
| | - Xiaohui Liu
- State Environmental Protection Scientific Observation and Research Station for Lake Dongtinghu (SEPSORSLD), National Engineering Laboratory for Lake Pollution Control and Ecological Restoration, State Key Laboratory of Environmental Criteria an Risk Assessment, Research Centre of Lake Environment, Chinese Research Academy of Environmental Sciences, Beijing 100012, People's Republic of China; School of Environment, Tsinghua University, Beijing 100084, People's Republic of China
| | - Ke Li
- State Environmental Protection Scientific Observation and Research Station for Lake Dongtinghu (SEPSORSLD), National Engineering Laboratory for Lake Pollution Control and Ecological Restoration, State Key Laboratory of Environmental Criteria an Risk Assessment, Research Centre of Lake Environment, Chinese Research Academy of Environmental Sciences, Beijing 100012, People's Republic of China; School of Environment, Beijing Normal University, Beijing 100088, People's Republic of China
| | - Shaoyong Lu
- State Environmental Protection Scientific Observation and Research Station for Lake Dongtinghu (SEPSORSLD), National Engineering Laboratory for Lake Pollution Control and Ecological Restoration, State Key Laboratory of Environmental Criteria an Risk Assessment, Research Centre of Lake Environment, Chinese Research Academy of Environmental Sciences, Beijing 100012, People's Republic of China.
| | - Xiaochun Guo
- State Environmental Protection Scientific Observation and Research Station for Lake Dongtinghu (SEPSORSLD), National Engineering Laboratory for Lake Pollution Control and Ecological Restoration, State Key Laboratory of Environmental Criteria an Risk Assessment, Research Centre of Lake Environment, Chinese Research Academy of Environmental Sciences, Beijing 100012, People's Republic of China
| | - Jian Zhang
- School of Environmental Science & Engineering, Shandong University, Jinan 250100, People's Republic of China
| | - Beidou Xi
- State Environmental Protection Scientific Observation and Research Station for Lake Dongtinghu (SEPSORSLD), National Engineering Laboratory for Lake Pollution Control and Ecological Restoration, State Key Laboratory of Environmental Criteria an Risk Assessment, Research Centre of Lake Environment, Chinese Research Academy of Environmental Sciences, Beijing 100012, People's Republic of China
| |
Collapse
|
27
|
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.
Collapse
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
| |
Collapse
|
28
|
Chen Q, Sun F, Zhou J, Lu Y, Li YY, Yu HY, Gu JS. Chlorine-resistant and internal-concentration-polarization-mitigated polyamide membrane via tethering poly(ethylene glycol) methacrylate. J Appl Polym Sci 2019. [DOI: 10.1002/app.47406] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Qing Chen
- College of Chemistry and Materials Science; Anhui Normal University; 189 Jiuhua Nanlu, Wuhu Anhui 241002 China
| | - Fei Sun
- College of Chemistry and Materials Science; Anhui Normal University; 189 Jiuhua Nanlu, Wuhu Anhui 241002 China
| | - Jin Zhou
- College of Chemistry and Materials Science; Anhui Normal University; 189 Jiuhua Nanlu, Wuhu Anhui 241002 China
- Department of Material and Chemical Engineering; Chizhou University; 199 Muzhi Road, Chizhou Anhui 247000 China
| | - Yao Lu
- College of Chemistry and Materials Science; Anhui Normal University; 189 Jiuhua Nanlu, Wuhu Anhui 241002 China
| | - Yuan-Yuan Li
- College of Chemistry and Materials Science; Anhui Normal University; 189 Jiuhua Nanlu, Wuhu Anhui 241002 China
| | - Hai-Yin Yu
- College of Chemistry and Materials Science; Anhui Normal University; 189 Jiuhua Nanlu, Wuhu Anhui 241002 China
| | - Jia-Shan Gu
- College of Chemistry and Materials Science; Anhui Normal University; 189 Jiuhua Nanlu, Wuhu Anhui 241002 China
| |
Collapse
|
29
|
Wei CJ, Wu WZ. Performance of single-pass and by-pass multi-step multi-soil-layering systems for low-(C/N)-ratio polluted river water treatment. CHEMOSPHERE 2018; 206:579-586. [PMID: 29778083 DOI: 10.1016/j.chemosphere.2018.05.035] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 04/03/2018] [Accepted: 05/06/2018] [Indexed: 06/08/2023]
Abstract
Two kinds of hybrid two-step multi-soil-layering (MSL) systems loaded with different filter medias (zeolite-ceramsite MSL-1 and ceramsite-red clay MSL-2) were set-up for the low-(C/N)-ratio polluted river water treatment. A long-term pollutant removal performance of these two kinds of MSL systems was evaluated for 214 days. By-pass was employed in MSL systems to evaluate its effect on nitrogen removal enhancement. Zeolite-ceramsite single-pass MSL-1 system owns outstanding ammonia removal capability (24 g NH4+-Nm-2d-1), 3 times higher than MSL-2 without zeolite under low aeration rate condition (0.8 × 104 L m-2.h-1). Aeration rate up to 1.6 × 104 L m-2.h-1 well satisfied the requirement of complete nitrification in first unit of both two MSLs. However, weak denitrification in second unit was commonly observed. By-pass of 50% influent into second unit can improve about 20% TN removal rate for both MSL-1 and MSL-2. Complete nitrification and denitrification was achieved in by-pass MSL systems after addition of carbon source with the resulting C/N ratio up to 2.5. The characters of biofilms distributed in different sections inside MSL-1 system well illustrated the nitrogen removal mechanism inside MSL systems. Two kinds of MSLs are both promising as an appealing nitrifying biofilm reactor. Recirculation can be considered further for by-pass MSL-2 system to ensure a complete ammonia removal.
Collapse
Affiliation(s)
- Cai-Jie Wei
- Department of Environmental Science, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, PR China; State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Wei-Zhong Wu
- Department of Environmental Science, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, PR China.
| |
Collapse
|
30
|
Zhao X, Hu Y, Zhao Y, Kumar L. Achieving an extraordinary high organic and hydraulic loadings with good performance via an alternative operation strategy in a multi-stage constructed wetland system. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:11841-11853. [PMID: 29446020 DOI: 10.1007/s11356-018-1464-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Accepted: 02/01/2018] [Indexed: 06/08/2023]
Abstract
In this study, a high organic loading rate of 58-146 g BOD5/m2 day with a hydraulic loading rate (HLR) of 1.63 m3/m2 day and retention time (RT) of 16 h was achieved to maximize the treatment capacity of a four-stage alum sludge-based constructed wetland (CW) system. An alternative operation strategy, i.e., the first stage anaerobic up-flow and the remaining stage tidal flow with effluent recirculation, was investigated to achieve the goal with good treatment performance of 82% COD, 91% BOD5, 92% SS, 94% NH4-N, and 82% TN removal. Two kinetic models, i.e., first-order model and Monod plus continuous stirred-tank reactor (CSTR) flow model, were employed for predicting the removal dynamics. The results showed that the tidal flow strategy enhances oxygen transport and diffusion, thus improving reduction of organics and NH4-N. Effluent recirculation could further increase elimination of organics by extending the interaction time and also benefit the denitrification process. In addition, denitrification could be further enhanced by anaerobic up-flow in the first stage.
Collapse
Affiliation(s)
- Xiaohong Zhao
- Key Laboratory of Water Supply and Drainage, Ministry of Housing and Urban-Rural Development, Chang'an University, Xi'an, 710061, People's Republic of China
| | - Yuansheng Hu
- Key Laboratory of Urban Stormwater System and Water Environment/R&D Centre for Sustainable Wastewater Treatment, Beijing University of Civil Engineering and Architecture, Ministry of Education, Beijing, 100044, People's Republic of China
| | - Yaqian Zhao
- Key Laboratory of Water Supply and Drainage, Ministry of Housing and Urban-Rural Development, Chang'an University, Xi'an, 710061, People's Republic of China.
- UCD Dooge Centre for Water Resources Research, School of Civil Engineering, University College Dublin, Newstead, Belfield, Dublin 4, Ireland.
| | - Lordwin Kumar
- UCD Dooge Centre for Water Resources Research, School of Civil Engineering, University College Dublin, Newstead, Belfield, Dublin 4, Ireland
- Department of Soil Water Land Engineering and Management, Vaugh School of Agricultural Engineering and Technology, Sam Higginbottom Institute of Agriculture, Technology & Sciences, Allahabad, India
| |
Collapse
|
31
|
Torrijos V, Ruiz I, Soto M. Effect of step-feeding on the performance of lab-scale columns simulating vertical flow-horizontal flow constructed wetlands. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:22649-22662. [PMID: 28812288 DOI: 10.1007/s11356-017-9925-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Accepted: 08/07/2017] [Indexed: 06/07/2023]
Abstract
The effect of step-feeding (untreated wastewater by-pass) on the performance of lab-scale columns simulating a hybrid vertical flow (VF)-horizontal flow (HF) constructed wetland (CW) system was studied. Step-feeding strategies have been adopted in several kinds of CW, but this is the first report about the use of step-feeding in VF + HF hybrid systems treating domestic wastewater. Applied loading rates were 7-11 g BOD5/m2 day and 2.1-3.4 g TN/m2 day (overall system). Removal efficiency reached 98% TSS and COD and 99% BOD5 on average, whilst a 50% by-pass improved TN removal from 31 to 50%. Maximum surface nitrification rate (5.5 g N/m2 day) was obtained in VF unit, whilst maximum denitrification rate (1.8 g N/m2 day) was observed in HF unit. Referred to the overall system, maximum surface nitrification and denitrification rates were 2.2 and 1.6 g N/m2 day, respectively. However, potential nitrifying and denitrifying activities (batch assays) were 15.0 and 58.9 g N/m2 day, respectively. Even at 50% by-pass, operational conditions in HF unit (dissolved oxygen, redox, COD/TN ratio) were not suitable enough for denitrification. However, methane emissions were not observed and nitrous oxide emissions were relatively low.
Collapse
Affiliation(s)
- Verónica Torrijos
- Department of Chemistry, University of A Coruña, Rúa da Fraga 10, 15008, A Coruña, Galiza, Spain
| | - Isabel Ruiz
- Department of Chemistry, University of A Coruña, Rúa da Fraga 10, 15008, A Coruña, Galiza, Spain
| | - Manuel Soto
- Department of Chemistry, University of A Coruña, Rúa da Fraga 10, 15008, A Coruña, Galiza, Spain.
| |
Collapse
|
32
|
Álvarez JA, Ávila C, Otter P, Kilian R, Istenič D, Rolletschek M, Molle P, Khalil N, Ameršek I, Mishra VK, Jorgensen C, Garfi A, Carvalho P, Brix H, Arias CA. Constructed wetlands and solar-driven disinfection technologies for sustainable wastewater treatment and reclamation in rural India: SWINGS project. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2017; 76:1474-1489. [PMID: 28953474 DOI: 10.2166/wst.2017.329] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
SWINGS was a cooperation project between the European Union and India, aiming at implementing state of the art low-cost technologies for the treatment and reuse of domestic wastewater in rural areas of India. The largest wastewater treatment plant consists of a high-rate anaerobic system, followed by vertical and horizontal subsurface flow constructed wetlands with a treatment area of around 1,900 m2 and a final step consisting of solar-driven anodic oxidation (AO) and ultraviolet (UV) disinfection units allowing direct reuse of the treated water. The implementation and operation of two pilot plants in north (Aligarh Muslim University, AMU) and central India (Indira Gandhi National Tribal University, IGNTU) are shown in this study. The overall performance of AMU pilot plant during the first 7 months of operation showed organic matter removal efficiencies of 87% total suspended solids, 95% 5-day biological oxygen demand (BOD5) and 90% chemical oxygen demand, while Kjeldahl nitrogen removal reached 89%. The UV disinfection unit produces water for irrigation and toilet flushing with pathogenic indicator bacteria well below WHO guidelines. On the other hand, the AO disinfection unit implemented at IGNTU and operated for almost a year has been shown to produce an effluent of sufficient quality to be reused by the local population for agriculture and irrigation.
Collapse
Affiliation(s)
- J A Álvarez
- AIMEN, C/. Relva, 27 A - Torneiros, Porriño - Pontevedra 36410, Spain E-mail: ; Both authors contributed equally to this manuscript
| | - C Ávila
- Catalan Institute for Water Research (ICRA), H2O Building, Scientific and Technological Park of the University of Girona, 17003 Girona, Spain; Both authors contributed equally to this manuscript
| | - P Otter
- AUTARCON, Franz-Ulrich-Straße 18 f, Kassel 34117, Germany
| | - R Kilian
- Kilian Water, Torupvej 4, Vrads - PORT 3, Bryrup 8654, Denmark
| | - D Istenič
- LIMNOS Company for Applied Ecology Ltd, Pozarnice 41, Brezovicapri, Ljubljani 1351, Slovenia
| | - M Rolletschek
- SolarSpring, Hanferstraße 28, Freiburg 79108, Germany
| | - P Molle
- IRSTEA, 5 rue de la Doua, Villeurbanne 69626, France
| | - N Khalil
- Department of Civil Engineering, Z H College of Engineering & Technology, Aligarh Muslim University (AMU), Aligarh 202002, UP, India
| | - I Ameršek
- LIVIPLANT d.o.o., Pečovnik 24, 3000 Celje, Slovenia
| | - V K Mishra
- Department of Environmental Science, Indira Gandhi National Tribal University (IGNTU), Amarkantak, MP, India
| | - C Jorgensen
- DHI Group, Agern Allé 5, 2970 Hørsholm, Denmark
| | - A Garfi
- GEMMA- Environmental Engineering and Microbiology Research Group, Universitat Politècnica de Catalunya-BarcelonaTech, c/ Jordi Girona, 1-3, Building D1, Barcelona 08034, Spain
| | - P Carvalho
- Department of Bioscience, Aarhus University, Ole Worms Alle 1, Bldg. 1135, Aarhus 8000, Denmark
| | - H Brix
- Department of Bioscience, Aarhus University, Ole Worms Alle 1, Bldg. 1135, Aarhus 8000, Denmark
| | - C A Arias
- Department of Bioscience, Aarhus University, Ole Worms Alle 1, Bldg. 1135, Aarhus 8000, Denmark
| |
Collapse
|
33
|
Effects of Selected Root Exudate Components on Nitrogen Removal and Development of Denitrifying Bacteria in Constructed Wetlands. WATER 2017. [DOI: 10.3390/w9060430] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
|
34
|
Gonzalo OG, Ruiz I, Soto M. Integrating pretreatment and denitrification in constructed wetland systems. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 584-585:1300-1309. [PMID: 28189310 DOI: 10.1016/j.scitotenv.2017.01.217] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Revised: 01/30/2017] [Accepted: 01/31/2017] [Indexed: 06/06/2023]
Abstract
The aim of this work was to study the operational characteristics and the efficiency of a compact constructed wetland system for municipal wastewater treatment that integrates denitrification in the pre-treatment unit. The proposed system was simulated by two units in series with effluent recirculation, the first one being an anoxic digester, conceived as a hydrolytic up flow sludge bed for solids hydrolysis and denitrification, and the second one a sand column that simulated the operation of a vertical flow constructed wetland. The hybrid system consisted of two small columns of 4 and 10.2cm in diameter (anoxic digester and vertical flow unit, respectively). The unplanted system was operated successively with synthetic and real municipal wastewater over a period of 136days. Hydraulic loading rate ranged from 212 to 318mm/day and surface loading rate from 122 to 145g/m2·day of chemical oxygen demand and 10-15g/m2·day of total nitrogen for the overall system. The overall system reached removals of 91% to 99% for total suspended solids, chemical oxygen demand and biochemical oxygen demand whilst total nitrogen removal ranged from 43% to 61%. In addition to suspended solids removal (up to 78%), the anoxic digester provided high denitrification rates (3-12gN/m2·day) whilst the vertical flow unit provided high nitrification rates (8-15gN/m2·day). Organic matter was mainly removed in the anoxic digester (63-82% chemical oxygen demand) and used for denitrification. Final effluent concentration was lower for ammonia (7.4±2.4mgN/L on average) than for nitrate (19.8±4.4mgN/L), denitrification appearing as the limiting step in nitrogen removal in the system. CH4 or N2O emissions were not detected in any of the units of the system indicating very low greenhouse gas emissions.
Collapse
Affiliation(s)
- O G Gonzalo
- Department of Physical Chemistry and Chemical Engineering l, University of A Coruña, Rúa da Fraga 10, 15008 A Coruña, Spain.
| | - I Ruiz
- Department of Physical Chemistry and Chemical Engineering l, University of A Coruña, Rúa da Fraga 10, 15008 A Coruña, Spain.
| | - M Soto
- Department of Physical Chemistry and Chemical Engineering l, University of A Coruña, Rúa da Fraga 10, 15008 A Coruña, Spain.
| |
Collapse
|
35
|
Ávila C, Pelissari C, Sezerino PH, Sgroi M, Roccaro P, García J. Enhancement of total nitrogen removal through effluent recirculation and fate of PPCPs in a hybrid constructed wetland system treating urban wastewater. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 584-585:414-425. [PMID: 28122684 DOI: 10.1016/j.scitotenv.2017.01.024] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 12/23/2016] [Accepted: 01/04/2017] [Indexed: 06/06/2023]
Abstract
The effect of effluent recirculation on the removal of total nitrogen (TN) and eight pharmaceuticals and personal care products (PPCPs) was evaluated during 9months in an experimental hybrid constructed wetland (CW) system applied in the treatment of urban wastewater. An Imhoff tank was followed by three stages of CWs (two 1.5-m2 vertical subsurface flow (VF) beds alternating feed-rest cycles, a 2-m2 horizontal (HF) and a 2-m2 free water surface (FWS) wetland in series). A fraction of the final effluent was recycled back to the Imhoff tank with a recirculation rate of 50% (hydraulic loading rate=0.37md-1). The system's performance varied throughout the study. In Period I (summer) consistently high load removal efficiencies of TN (89±5%) and a removal rate of 6.6±1.4gTNm-2d-1 were exhibited. In Period II (fall), the poor performance of the FWS during the senescence of macrophytes caused a large increase in organic matter, solids and nutrient concentrations, drastically deteriorating water quality. The determination of PPCPs was conducted during this period. Recalcitrant compounds, namely sulfamethoxazole, carbamazapine, TCEP and sucralose were negligibly removed in all CWs. However, noteworthy was the ≈30% removal of sucralose in the VF wetland. Caffeine (80%) and fluoxetine (27%) showed similar elimination rates in both VF and HF units, whereas trimethoprim and DEET were significantly better removed in the VF than in the HF. The concentration of the four latter compounds showed a severe increase in the FWS, indicating possible desorption from the sediment/biomass during adverse conditions. Harvesting of the aboveground biomass in this unit returned the system's performance back to normality (Period III), achieving 77±7% TN removal despite the winter season, proving effluent recirculation as an effective strategy for TN removal in hybrid CW systems when stringent restrictions are in place.
Collapse
Affiliation(s)
- Cristina Ávila
- GEMMA- Environmental Engineering and Microbiology Research Group, Department of Civil and Environmental Engineering, Universitat Politècnica de Catalunya-BarcelonaTech, c/ Jordi Girona, 1-3, Building D1, E-08034 Barcelona, Spain; ICRA, Catalan Institute for Water Research, Scientific and Technological Park of the University of Girona, Emili Grahit, 101, E-17003 Girona, Spain.
| | - Catiane Pelissari
- GESAD-Decentralized Sanitation Research Group, Department of Sanitary and Environmental Engineering, Federal University of Santa Catarina, Trindade, Florianópolis, Santa Caterina CEP 88040-900, Brazil
| | - Pablo H Sezerino
- GESAD-Decentralized Sanitation Research Group, Department of Sanitary and Environmental Engineering, Federal University of Santa Catarina, Trindade, Florianópolis, Santa Caterina CEP 88040-900, Brazil
| | - Massimiliano Sgroi
- Department of Civil Engineering and Architecture, University of Catania, Viale A. Doria 6, 95125 Catania, Italy
| | - Paolo Roccaro
- Department of Civil Engineering and Architecture, University of Catania, Viale A. Doria 6, 95125 Catania, Italy
| | - Joan García
- GEMMA- Environmental Engineering and Microbiology Research Group, Department of Civil and Environmental Engineering, Universitat Politècnica de Catalunya-BarcelonaTech, c/ Jordi Girona, 1-3, Building D1, E-08034 Barcelona, Spain
| |
Collapse
|
36
|
Patil S, Chakraborty S. Effects of step-feeding and intermittent aeration on organics and nitrogen removal in a horizontal subsurface flow constructed wetland. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2017; 52:403-412. [PMID: 27973979 DOI: 10.1080/10934529.2016.1262608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The effect of step feed strategy and intermittent aeration on removal of chemical oxygen demand (COD) and nitrogen was investigated in a laboratory scale horizontal subsurface flow constructed wetland (HSSFCW). Wetland was divided into four zones along the length (zone I to IV), and influent was introduced into first and third zones by step feeding. Continuous study was carried out in four phases. In phases I to III, 30% of influent was bypassed to zone III for denitrification along with organics removal. Intermittent aeration was provided only in zone II at 2.5 L/min for 4 h/day, during phases II, III and IV. In phase I, 87% COD and 43% NH4+-N (ammonia-nitrogen) removal were obtained from influents of 331 and 30 mg/L, respectively. In phase II study, external aeration resulted in 97% COD and 71% NH4+-N removal in the wetland. In phase IV, 40% of feed was delivered to zone III. Higher supply of organic in zone III resulted in higher denitrification, and total nitrogen removal rate increased to 70% from 56%. In the final effluent, concentration of NO3--N was 9-11 mg/L in phase I to III and decreased to 4 mg/L in phase IV. Batch study showed that COD and NH4+-N removal followed first order kinetics in different zones of wetland.
Collapse
Affiliation(s)
- Sagar Patil
- a Department of Civil Engineering , Indian Institute of Technology Guwahati , Assam , India
| | - Saswati Chakraborty
- a Department of Civil Engineering , Indian Institute of Technology Guwahati , Assam , India
| |
Collapse
|