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Nguyen XC, Tran TCP, Hoang VH, Nguyen TP, Chang SW, Nguyen DD, Guo W, Kumar A, La DD, Bach QV. Combined biochar vertical flow and free-water surface constructed wetland system for dormitory sewage treatment and reuse. Sci Total Environ 2020; 713:136404. [PMID: 32019008 DOI: 10.1016/j.scitotenv.2019.136404] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 12/26/2019] [Accepted: 12/27/2019] [Indexed: 06/10/2023]
Abstract
A two-stage treatment system that included vertical flow (VF) and free-water surface (FWS) constructed wetlands was investigated for the dual purposes of sewage treatment and reuse. The VF included four layers (biochar, sand, gravel, and sandy soil), and the FWS was installed after the VF and used as a polishing tank. Two types of local plants, namely Colocasia esculenta and Canna indica, were planted in the VF and FWS, respectively. The system operated for approximately six months, and the experimental period was categorized into four stages that corresponded to changes in the hydraulic loading rate (HLR) (0.02-0.12 m/d). The removal efficiencies for total suspended solids (TSS), chemical oxygen demand (COD), biological oxygen demand (BOD5), ammonia (NH4-N), and total coliform (Tcol) were 71 ± 11%, 73 ± 13%, 79 ± 11%, 91 ± 3%, and 70 ± 20%, respectively. At HLRs of 0.04-0.06 m/d, the COD and BOD5 levels satisfied Vietnam's irrigation standards, with removable rates of 64% and 88%, respectively, and the TSS and Tcol levels satisfied Vietnam's standards for potable water. Furthermore, the NO3-N levels satisfied the reuse limits, whereas the NH4-N levels exceeded the reuse standards. At high HLRs (e.g., 0.12 m/d), all the effluent parameters, except Tcol and NO3-N, exceeded the standards.
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Affiliation(s)
- X Cuong Nguyen
- Center for Advanced Chemistry, Institute of Research and Development, Duy Tan University, 03 Quang Trung, Da Nang, Vietnam
| | - T C Phuong Tran
- Faculty of Environmental Engineering Technology, Hue University, Quang Tri Campus, Vietnam
| | - V Hoan Hoang
- Faculty of Environmental Engineering Technology, Hue University, Quang Tri Campus, Vietnam
| | - T Phuong Nguyen
- Faculty of Environmental Engineering Technology, Hue University, Quang Tri Campus, Vietnam
| | - Soon Woong Chang
- Department of Environmental Energy Engineering, Kyonggi University, Suwon, Republic of Korea
| | - Dinh Duc Nguyen
- Department of Environmental Energy Engineering, Kyonggi University, Suwon, Republic of Korea; Nguyen Tat Thanh University, 300A Nguyen Tat Thanh, District 4, Ho Chi Minh City, 755414, Vietnam
| | - Wenshan Guo
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NWS 2007, Australia
| | - Ashok Kumar
- Department of Biotechnology and Bioinformatics, Jaypee University of Information Technology, Waknaghat, Solan 173 234, India
| | - Duong Duc La
- Institute of Chemistry and Materials, Hanoi, Vietnam
| | - Quang-Vu Bach
- Sustainable Management of Natural Resources and Environment Research Group, Faculty of Environment and Labour Safety, Ton Duc Thang University, Ho Chi Minh City, Vietnam.
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Ryu J, Kim K, Oh M, Shin J. Why environmental and social benefits should be included in cost-benefit analysis of infrastructure? Environ Sci Pollut Res Int 2019; 26:21693-21703. [PMID: 31129900 DOI: 10.1007/s11356-019-05475-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 05/14/2019] [Indexed: 06/09/2023]
Abstract
A gradual increase in the importance of water environment infrastructure has provided an opportunity to bring in various initiatives for the supply of sewage. Such initiatives include the dissemination of public sewage systems and the use of subcontractors in management of sewage systems. However, despite the existence of various methods to increase the rate of sewage supply, there are few studies analyzing each alternative in terms of social, economic, and environmental aspects. Therefore, we investigated investment directions for water environment infrastructure facilities related to the supply of sewage treatment systems in rural areas through cost-benefit analysis. We analyzed the economic costs and social benefits of two sewage treatment systems: installation of a public sewage treatment system and utilization of a private sewage treatment system via service contract. When we considered only economic costs and benefits, the benefit-cost ratio for the public system (0.02) was smaller than that for the private system (0.264). However, the results of the two alternatives changed when we considered the social benefits to people in urban areas from establishment of public sewage treatment systems in rural areas. To be specific, by considering the social benefits for non-rural areas, this study found that the benefit-cost ratio for the public system increased to 0.267, which was higher than the ratio for the private system. Based on these results, we propose appropriate operations and management plans for supplying sewage treatment systems to rural areas. Further, this study indicates that policymakers who conduct cost-benefit analyses of infrastructure related to water environments should consider all social, environmental, and economic factors that can alter the analysis results.
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Affiliation(s)
- Jaena Ryu
- Water and Land Research Group, Korea Environment Institute, 370 Sicheong-daero, Sejong-si, 30147, South Korea
| | - Kyungah Kim
- Technology Management, Economics, and Policy Program, College of Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Myoungjin Oh
- Department of Industrial and Management Systems Engineering, College of Engineering, Kyung Hee University, 1732 Deogyeong-daero, Giheung-gu, Yongin, Gyeonggi, 17104, South Korea
| | - Jungwoo Shin
- Department of Industrial and Management Systems Engineering, College of Engineering, Kyung Hee University, 1732 Deogyeong-daero, Giheung-gu, Yongin, Gyeonggi, 17104, South Korea.
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Zhao X, Zhang ZF, Xu L, Liu LY, Song WW, Zhu FJ, Li YF, Ma WL. Occurrence and fate of benzotriazoles UV filters in a typical residential wastewater treatment plant in Harbin, China. Environ Pollut 2017; 227:215-222. [PMID: 28472737 DOI: 10.1016/j.envpol.2017.04.072] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Revised: 03/16/2017] [Accepted: 04/16/2017] [Indexed: 05/25/2023]
Abstract
Benzotriazoles (BTs) UV filters are widely used as ultraviolet absorbents for our daily products, which received increasing attention in the past decades. Residential wastewater treatment plant (WWTP) is both an important sink for wastewater and a key pollution source for receiving water for these chemicals. In this study, pretreatment and gas chromatography-tandem mass spectrometry analysis method were developed to determine the occurrence and fate of 9 BTs UV filters in wastewater and sludge from the WWTP with anaerobic-oxic treatment process (A/O) and biological aerated filter treatment process (BAF). Totally, 81 wastewater samples and 11 sludge samples were collected in four seasons. In wastewater, UV-326 and UV-329 were frequently detected, while the highest mean concentrations were detected for UV-234 and UV-329. The concentrations were in the range of <LOQs up to several hundred nanograms per liter. The removal efficiency of BTs UV filters was >85% in A/O process and 60-77% in BAF process except for UV-350, which was more difficult to remove with lower removal efficiencies of 33.3% for both A/O and BAF. All the target chemicals except for UV-320 were detected in sludge samples with the mean concentration ranging from 0.90 ng/g to 303.39 ng/g. There was no significant difference with concentrations and removal efficiency among different seasons. Higher detection frequency and concentration of BTs UV filters in downstream of the receiving water system indicated the contribution of effluent of the WWTP. Compared with other rivers, the lower concentrations in surface water in the Songhua River indicated light pollution status with of BTs UV filters.
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Affiliation(s)
- Xue Zhao
- International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Zi-Feng Zhang
- International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Lei Xu
- International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Li-Yan Liu
- International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Wei-Wei Song
- International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Fu-Jie Zhu
- International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Yi-Fan Li
- International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Wan-Li Ma
- International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China.
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