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Moonkawin J, Huynh LT, Schneider MY, Fujii S, Echigo S, Nguyen LPH, Hoang THT, Huynh HT, Harada H. Challenges to Accurate Estimation of Methane Emission from Septic Tanks with Long Emptying Intervals. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:16575-16584. [PMID: 37856469 PMCID: PMC10621000 DOI: 10.1021/acs.est.3c05724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 09/18/2023] [Accepted: 09/20/2023] [Indexed: 10/21/2023]
Abstract
Septic tanks in low- and middle-income countries are often not emptied for a long time, potentially resulting in poor pollutant removal efficiency and increased greenhouse gas emissions, including methane (CH4). We examined the impact of long emptying intervals (4.0-23 years) on the biochemical oxygen demand (BOD) removal efficiency of 15 blackwater septic tanks and the CH4 emission rates of 23 blackwater septic tanks in Hanoi. The average BOD removal efficiency was 37% (-2-65%), and the average CH4 emission rate was 10.9 (2.2-26.8) g/(cap·d). The emptying intervals were strongly negatively correlated with BOD removal efficiency (R = -0.676, p = 0.006) and positively correlated with CH4 emission rates (R = 0.614, p = 0.001). CH4 emission rates were positively correlated with sludge depth (R = 0.596, p = 0.002), but against expectation, negatively correlated with BOD removal efficiency (R = -0.219, p = 0.451). These results suggest that shortening the emptying interval improves the BOD removal efficiency and reduces the CH4 emission rate. Moreover, the CH4 emission estimation of the Intergovernmental Panel on Climate Change, which is a positive conversion of BOD removal, might be inaccurate for septic tanks with long emptying intervals. Our findings suggest that emptying intervals, sludge depth, and per-capita emission factors reflecting long emptying intervals are potential parameters for accurately estimating CH4 emissions from septic tanks.
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Affiliation(s)
- Jakpong Moonkawin
- Graduate
School of Global Environmental Studies, Kyoto University, Kyoto 606-8501, Japan
| | - Loi T. Huynh
- Faculty
of Environment, School of Technology, Van
Lang University, Ho Chi Minh City 70000, Viet Nam
| | - Mariane Y. Schneider
- Next
Generation Artificial Intelligence Research Center & School of
Information Science and Technology, The
University of Tokyo, 113-8656 Tokyo, Japan
- BIOMATH,
Department of Data Analysis and Mathematical Modelling, Ghent University, Coupure Links 653, Ghent 9000, Belgium
- Centre
for Advanced Process Technology for Urban Resource Recovery (CAPTURE), Frieda Saeysstraat 1, Gent 9000, Belgium
| | - Shigeo Fujii
- Graduate
School of Global Environmental Studies, Kyoto University, Kyoto 606-8501, Japan
| | - Shinya Echigo
- Graduate
School of Global Environmental Studies, Kyoto University, Kyoto 606-8501, Japan
| | - Lien P. H. Nguyen
- School of
Chemistry and Life Science, Hanoi University
of Science and Technology, Hanoi 10000, Viet Nam
| | - Thu-Huong T. Hoang
- School of
Chemistry and Life Science, Hanoi University
of Science and Technology, Hanoi 10000, Viet Nam
| | - Hai T. Huynh
- School of
Chemistry and Life Science, Hanoi University
of Science and Technology, Hanoi 10000, Viet Nam
| | - Hidenori Harada
- Graduate
School of Asian and African Area Studies, Kyoto University, Kyoto 606-8501, Japan
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Escobedo E, Cho K, Chang YS. Electrochemical activation of hydrogen peroxide, persulfate, and free chlorine using sacrificial iron anodes for decentralized wastewater treatment. JOURNAL OF HAZARDOUS MATERIALS 2022; 423:127068. [PMID: 34523470 DOI: 10.1016/j.jhazmat.2021.127068] [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: 05/26/2021] [Revised: 08/26/2021] [Accepted: 08/26/2021] [Indexed: 06/13/2023]
Abstract
Increasing contamination of groundwater by heavy metals could potentially hamper the basic sanitation based on septic system in developing countries. Therefore, this paper evaluated wastewater treatment by electrochemical activation of hydrogen peroxide (EAHP), persulfate (EAP), and free chlorine (EAFC) to simultaneously eliminate aqueous organic matter and heavy metals. Sacrificial iron anodes under galvanostatic regime activated the batch-injected oxidants under uncontrolled pH, to avoid extra cost of control in decentralized processes (e.g., household use) to treat domestic wastewater. Response surface methodology (RSM) was used to determine the optimized conditions for EAP ([persulfate]0 = 25 mM, 24.4 mA/cm2), EAFC ([free chlorine]0 = 35.5 mM, 44.4 mA/cm2), and EAHP ([H2O2]0 = 91.1 mM, 45 mA/cm2) towards total organic carbon (TOC) removal. Treatment of real wastewater under optimum conditions significantly reduced chemical oxygen demand (COD) and TOC in all treatments, complying with lenient effluent standards as well as the added benefit of complete As(V) and Cr(VI) removal. Although EAP and EAFC provided superior removal of TOC (70-75%) and COD (73-100%) within 3 h, respectively, effluent toxicity and operation cost (76-85 USD/m3) were relatively high. EAHP was the best available option to secure non-toxic effluent with the least cost (63 USD/m3).
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Affiliation(s)
- Ericson Escobedo
- Division of Environmental Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea
| | - Kangwoo Cho
- Division of Environmental Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea; Institute for Convergence Research and Education in Advanced Technology, Yonsei University International Campus, 21983 Incheon, Republic of Korea.
| | - Yoon-Seok Chang
- Division of Environmental Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea.
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Watanabe R, Harada H, Yasui H, Le TV, Fujii S. Exfiltration and infiltration effect on sewage flow and quality: a case study of Hue, Vietnam. ENVIRONMENTAL TECHNOLOGY 2021; 42:1747-1757. [PMID: 31657999 DOI: 10.1080/09593330.2019.1680739] [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: 04/02/2019] [Accepted: 10/09/2019] [Indexed: 06/10/2023]
Abstract
Sewage generated in Southeast Asia is typically characterized by small per-capita flow and low concentration. This study investigated the impacts of exfiltration (leaking-out) and infiltration (leaking-in) on sewage flow and quality in Hue, Vietnam. Sewage flow and quality were continuously monitored at the sewer outlet of a residential drainage area for 68 and 82 days during dry and rainy seasons, respectively. Infiltration was estimated based on the least sewage flow before morning. Lithium tracer tests were conducted to estimate the exfiltration ratio. The results indicated that sewage of the target sewer was weaker than the typical weak-strength sewage even on no-rain days of the dry season. Monitoring of electrical conductivity indicated that rainfall persistently decreased the sewage concentration for a maximum duration of 228 h. The estimated infiltration accounted for 11% and 62% of the total sewage inflow to the sewer during dry and rainy seasons, respectively. The tracer test indicated that exfiltration ratios during the dry and rainy seasons were 65.6% and 24.0%, respectively. As a result of developing the water balance, only 23% of the water supplied to the area reached the sewer outlet in the dry season, while 123% flowed in the rainy season. These results demonstrate that exfiltration decreased the sewage flow in the dry season, while infiltration significantly increased the sewage flow and decreased the sewage concentration in the rainy season. To the best of our knowledge, this is the first study to quantify the impacts of infiltration and exfiltration on sewage in Southeast Asia.
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Affiliation(s)
- Ryuichi Watanabe
- Department of Environmental Engineering, Graduate School of Engineering, Kyoto University, Kyoto, Japan
| | - Hidenori Harada
- Graduate School of Global Environmental Studies, Kyoto University, Kyoto, Japan
| | - Hidenari Yasui
- Faculty of Environmental Engineering, The University of Kitakyusyu, Kitakyusyu, Japan
| | - Tuan Van Le
- Faculty of Environmental Science, Hue University of Sciences, Hue, Vietnam
| | - Shigeo Fujii
- Graduate School of Global Environmental Studies, Kyoto University, Kyoto, Japan
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Huynh LT, Harada H, Fujii S, Nguyen LPH, Hoang THT, Huynh HT. Greenhouse Gas Emissions from Blackwater Septic Systems. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:1209-1217. [PMID: 33403851 PMCID: PMC7818654 DOI: 10.1021/acs.est.0c03418] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 12/18/2020] [Accepted: 12/23/2020] [Indexed: 06/01/2023]
Abstract
Septic systems are potentially a significant source of greenhouse gases (GHGs). The present study investigated GHGs from the blackwater septic systems that are widely used especially in low- and middle-income countries. Ten blackwater septic tanks in Hanoi, Vietnam, were investigated using the floating chamber method. The average methane and carbon dioxide emission rates measured at the first compartment (65% of total capacity) of the septic tanks were 11.92 and 20.24 g/cap/day, respectively, whereas nitrous oxide emission was negligible. Methane emission rate was significantly correlated with septage oxidation-reduction potential (ORP) (R = -0.67, p = 0.034), chemical oxygen demand mass (R = 0.78, p = 0.007), and biochemical oxygen demand mass (R = 0.78, p = 0.008), whereas it was not significantly correlated with water temperature (R = 0.26, p = 0.47) and dissolved oxygen (R = -0.59, p = 0.075) within the limited range: 30.6-31.7 °C and 0.03-0.34 mg-O2/L. The methane emission rates from septic tanks accumulating septage for >5 years were significantly higher than those at 0-5 years (p = 0.016). These results suggest that lower ORP and higher biodegradable carbon mass, in association with longer septage storage periods are key conditions for methane emissions. To the best of our knowledge, this is the first study to characterize GHG emissions from septic systems.
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Affiliation(s)
- Loi Tan Huynh
- Graduate
School of Engineering, Kyoto University, Yoshida-honmachi, Sakyo, Kyoto 606-8501, Japan
| | - Hidenori Harada
- Graduate
School of Asian and African Area Studies, Kyoto University, 46
Yoshida-shimoadachi, Sakyo, Kyoto 606-8501, Japan
| | - Shigeo Fujii
- Graduate
School of Global Environmental Studies, Kyoto University, Yoshida-honmachi, Sakyo, Kyoto 606-8501, Japan
| | - Lien Pham Hong Nguyen
- School
of Environmental Science and Technology, Hanoi University of Science and Technology, Hanoi 10000, Vietnam
| | - Thu-Huong Thi Hoang
- School
of Environmental Science and Technology, Hanoi University of Science and Technology, Hanoi 10000, Vietnam
| | - Hai Trung Huynh
- School
of Environmental Science and Technology, Hanoi University of Science and Technology, Hanoi 10000, Vietnam
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Nguyen NT, Liu M, Katayama H, Takemura T, Kasuga I. Association of the colistin resistance gene mcr-1 with faecal pollution in water environments in Hanoi, Vietnam. Lett Appl Microbiol 2020; 72:275-282. [PMID: 33099779 DOI: 10.1111/lam.13421] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 09/30/2020] [Accepted: 10/20/2020] [Indexed: 11/29/2022]
Abstract
Colistin is one of the antibiotics of last resort for human health. However, the dissemination of the plasmid-mediated colistin resistance gene mcr-1 is of great concern globally. In the One Health framework, the environment is an important component for managing antimicrobial resistance. However, little information is available concerning the prevalence of mcr-1 in water environments. We aimed to reveal the prevalence of mcr-1 in different water environments in Hanoi, Vietnam. Quantitative PCR was applied to detect mcr-1 in four urban drainages receiving untreated domestic wastewater, three rivers, five lakes and two groundwater samples. Urban drainages contained higher concentrations of mcr-1, suggesting that urban residents carry the gene. The class 1 integron-integrase gene was identified as a good surrogate of antibiotic resistance genes including mcr-1. A significant correlation was found between the levels of mcr-1 and the human-specific cross-assembly phage, which is an indicator of human faecal pollution. These results indicated that the primary source of mcr-1 in urban water environments is human faeces, which is consistent with the fact that most domestic wastewater is untreated in Hanoi. The control of untreated wastewater is critical for alleviating the spread of mcr-1 in water environments in Vietnam.
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Affiliation(s)
- N T Nguyen
- Vietnam Research Station, Center for Infectious Disease Research in Asia and Africa, Institute of Tropical Medicine, Nagasaki University, Hanoi, Vietnam.,Master's Program in Environmental Engineering, VNU Vietnam Japan University, Hanoi, Vietnam
| | - M Liu
- Department of Urban Engineering, School of Engineering, The University of Tokyo, Tokyo, Japan
| | - H Katayama
- Department of Urban Engineering, School of Engineering, The University of Tokyo, Tokyo, Japan
| | - T Takemura
- Vietnam Research Station, Center for Infectious Disease Research in Asia and Africa, Institute of Tropical Medicine, Nagasaki University, Hanoi, Vietnam
| | - I Kasuga
- Master's Program in Environmental Engineering, VNU Vietnam Japan University, Hanoi, Vietnam.,Department of Urban Engineering, School of Engineering, The University of Tokyo, Tokyo, Japan
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Pathogen flows from on-site sanitation systems in low-income urban neighborhoods, Dhaka: A quantitative environmental assessment. Int J Hyg Environ Health 2020; 230:113619. [PMID: 32942223 DOI: 10.1016/j.ijheh.2020.113619] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 08/16/2020] [Accepted: 08/27/2020] [Indexed: 01/17/2023]
Abstract
BACKGROUND Despite wide usage of on-site sanitation, there is limited field-based evidence on the removal or release of pathogens from septic tanks and other primary treatment systems, such as anaerobic baffled reactors (ABR). In two low-income areas in Dhaka, we conducted a cross-sectional study to explore pathogen loads discharged from commonly used on-site sanitation-systems and their transport in nearby drains and waterways. METHODS We collected samples of drain water, drain sediment, canal water, and floodwater from April-October 2019. Sludge, supernatant, and effluent samples were also collected from septic tanks and ABRs. We investigated the presence and concentration of selected enteric pathogens (Shigella, Vibrio cholerae (V. cholerae), Salmonella Typhi (S. Typhi), Norovirus Genogroup-II (NoV-GII), and Giardia) and presence of Cryptosporidium in these samples using quantitative polymerase chain reaction (qPCR).The equivalent genome copies (EGC) of individual pathogens were estimated in each sample by interpolation of the mean Ct value to the corresponding standard curve and the dilution factor for each sample type. Absolute quantification was expressed as log10 EGC per 100 mL for the water samples and log10 EGC per gram for the sediment samples. RESULTS Among all samples tested (N = 151), 89% were contaminated with Shigella, 68% with V. cholerae and NoV-GII, 32% with Giardia, 17% with S. Typhi and 6% with Cryptosporidium. A wide range of concentration of pathogens [range: mean log10 concentration of Giardia = 0.74 EGC/100 mL in drain ultrafiltration samples to mean log10 concentration of NoV-GII and Giardia = 7.11 EGC/100 mL in ABR sludge] was found in all environmental samples. The highest pathogen concentrations were detected in open drains [range: mean log10 concentration = 2.50-4.94 EGC/100 mL], septic tank effluent [range: mean log10 concentration = 3.32-4.65 EGC/100 mL], and ABR effluent [range: mean log10 concentration = 2.72-5.13 EGC/100 mL]. CONCLUSIONS High concentrations of pathogens (particularly NoV-GII, V.cholerae and Shigella) were frequently detected in environmental samples from two low-income urban neighbourhoods of Dhaka city. The numerous environmental exposure pathways for children and adults make these findings of public health concern. These results should prompt rethinking of how to achieve safe sanitation solutions that protect public health in dense low-income areas. In particular, improved management and maintenance regimes, further treatment of liquid effluent from primary treatment processes, and appropriate application of onsite, decentralised and offsite sanitation systems given the local context.
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Naing W, Harada H, Fujii S, Hmwe CSS. Informal Emptying Business in Mandalay: Its Reasons and Financial Impacts. ENVIRONMENTAL MANAGEMENT 2020; 65:122-130. [PMID: 31828411 PMCID: PMC6960235 DOI: 10.1007/s00267-019-01228-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 11/14/2019] [Indexed: 06/02/2023]
Abstract
Globally, 2.8 billion people use on-site sanitation facilities, which need regular emptying of accumulated fecal sludge. Illegal dumping from informal emptying businesses, one of the major challenges in environmental management, is widely observed. Considering Mandalay, Myanmar, this study aimed to determine why informal emptying businesses are selected and estimate the lost revenue for a formal emptying service provider (FP) due to the informal businesses. We interviewed 400 households on their recognition and experiences regarding emptying services and willingness-to-pay for improved service. Revenue loss was estimated by comparing the present and theoretical maximum revenues. Results showed that 91.0% of households recognized FP only. Among 134 emptying-experienced households, 32.8%, 59.7%, and 4.5% chose FP with legal contact, FP with illegal contact, and informal service providers, respectively. The service fees from FP with illegal contact did not become revenue for FP; this was a major informal emptying business in the city. Differently from previous studies, the major illegal dumping was done by FP in this area. A great financial loss was estimated that FP lost 76.5% of the theoretical maximum revenue due to informal business. Logistic regression analysis indicated people's intention to shorten the waiting time through illegal contact, even by paying a higher fee. As emptying services are typically required immediately after fecal sludge is over-accumulated, shorter waiting times and faster contact methods were the reasons why the informal business was selected. Less bureaucratic and more customer friendly system could reduce revenue loss, charge more, and increase profits.
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Affiliation(s)
- Wutyi Naing
- Graduate School of Engineering, Department of Environmental Engineering, Kyoto University, Yoshida-honmachi, Sakyo, Kyoto, 606-8501, Japan
| | - Hidenori Harada
- Graduate School of Global Environmental Studies, Kyoto University, Yoshida-honmachi, Sakyo, Kyoto, 606-8501, Japan.
| | - Shigeo Fujii
- Graduate School of Global Environmental Studies, Kyoto University, Yoshida-honmachi, Sakyo, Kyoto, 606-8501, Japan
| | - Chaw Su Su Hmwe
- Department of Chemical Engineering, Mandalay Technological University, Patheingyi, Myanmar
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Thomes MW, Vaezzadeh V, Zakaria MP, Bong CW. Use of sterols and linear alkylbenzenes as molecular markers of sewage pollution in Southeast Asia. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:31555-31580. [PMID: 31440968 DOI: 10.1007/s11356-019-05936-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 07/11/2019] [Indexed: 06/10/2023]
Abstract
Southeast Asia has undergone rapid developments in terms of urbanization, economic and population growth. The progress in sewerage treatment infrastructure has not kept pace with such developments. The inadequacy and inefficiency of sewerage systems has prompted the release of untreated sewage into the aquatic environment of Southeast Asia causing many waterborne illnesses since surface water is utilized for recreational, agricultural and aquaculture purposes and, above all, as a source of water intake in Southeast Asia. This paper will review the current data on molecular markers of sewage pollution including sterols and linear alkylbenzenes (LABs) in Southeast Asian aquatic environment to clarify the state of sewage pollution and the competence of sewage treatment plants (STPs) in this area. Despite the importance of sewage pollution research in the region, the number of studies using molecular markers to trace the sources of sewage pollution is limited. So far, indicators of sewage pollution have been investigated in aquatic environments of Indonesia, Vietnam, Malaysia, the Philippines, Thailand, Cambodia and Brunei among Southeast Asian countries. The concentrations and diagnostic ratios of faecal sterols and LABs show the release of untreated and primary treated urban waste into water bodies of these countries. Further studies are required to fill the data gaps in Southeast Asia and come to a better understanding of the trends of sewage pollution in this part of the world. Graphical abstract.
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Affiliation(s)
- Margaret William Thomes
- Institute of Ocean and Earth Sciences, University of Malaya, 50603, Kuala Lumpur, Malaysia
- Institute for Advanced Studies, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Vahab Vaezzadeh
- Institute of Ocean and Earth Sciences, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Mohamad Pauzi Zakaria
- Institute of Ocean and Earth Sciences, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Chui Wei Bong
- Institute of Ocean and Earth Sciences, University of Malaya, 50603, Kuala Lumpur, Malaysia.
- Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia.
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Gold M, Harada H, Therrien JD, Nishida T, Cunningham M, Semiyaga S, Fujii S, Dorea C, Nguyen VA, Strande L. Cross-country analysis of faecal sludge dewatering. ENVIRONMENTAL TECHNOLOGY 2018; 39:3077-3087. [PMID: 28866955 DOI: 10.1080/09593330.2017.1374472] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Accepted: 08/21/2017] [Indexed: 06/07/2023]
Abstract
Dewatering of faecal sludge (FS) is indispensable for adequate FS management. However, comprehensive knowledge is lacking on FS dewatering performance. This study compared the dewatering performance of FS from different countries and onsite sanitation technologies, to assess influential characteristics on dewatering, and to compare dewatering performance of FS with wastewater sludge. We collected 73 FS samples from septic tanks, lined pit latrines, unlined pit latrines and johkasou tanks in Uganda, Vietnam and Japan, and 18 samples of wastewater sludge in Switzerland. Capillary suction time (CST) and total solids (TS) of centrifuged sludge (%TSfinal) were determined as metrics of dewatering rate and dewaterability, respectively, together with relevant sludge characteristics. Data were analysed by bootstrapping comparison of median results of each sample category and by bootstrapping multiple regression analysis to quantify the relative importance of sludge characteristics on dewatering performance. Results showed that the dewatering rate was significantly different between FS from different technologies, whereas dewaterability was significantly different within the same technology. FS had a significantly lower dewatering rate than wastewater sludge. In contrast, FS dewaterability was greater than wastewater sludge. However, this could be attributed to higher concentrations of sand in FS. Electrochemical properties such as NH4-N and surface charge had the strongest correlation to dewatering rate, and solid properties such as sand content and total volatile solids to dewaterability. The results identify potential characteristics that could explain and predict the high variability of FS dewatering performance that is observed in the field.
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Affiliation(s)
- Moritz Gold
- a Eawag: Swiss Federal Institute of Aquatic Science and Technology, Sandec: Department of Water , Sanitation and Solid Waste for Development , Duebendorf , Switzerland
| | - Hidenori Harada
- b Graduate School of Global Environmental Studies , Kyoto University , Kyoto , Japan
| | - Jean-David Therrien
- a Eawag: Swiss Federal Institute of Aquatic Science and Technology, Sandec: Department of Water , Sanitation and Solid Waste for Development , Duebendorf , Switzerland
- c Département de génie civil et de génie des eaux , Université Laval , Quebec , Canada
| | - Takahiro Nishida
- b Graduate School of Global Environmental Studies , Kyoto University , Kyoto , Japan
| | - Michael Cunningham
- a Eawag: Swiss Federal Institute of Aquatic Science and Technology, Sandec: Department of Water , Sanitation and Solid Waste for Development , Duebendorf , Switzerland
| | - Swaib Semiyaga
- d Department of Civil and Environmental Engineering, College of Engineering, Design, Art and Technology , Makerere University , Kampala , Uganda
| | - Shigeo Fujii
- b Graduate School of Global Environmental Studies , Kyoto University , Kyoto , Japan
| | - Caetano Dorea
- c Département de génie civil et de génie des eaux , Université Laval , Quebec , Canada
| | - Viet-Anh Nguyen
- e Institute of Environmental Science and Engineering, Hanoi University of Civil Engineering , Hanoi , Vietnam
| | - Linda Strande
- a Eawag: Swiss Federal Institute of Aquatic Science and Technology, Sandec: Department of Water , Sanitation and Solid Waste for Development , Duebendorf , Switzerland
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Watanabe Y, Bach LT, Van Dinh P, Prudente M, Aguja S, Phay N, Nakata H. Ubiquitous Detection of Artificial Sweeteners and Iodinated X-ray Contrast Media in Aquatic Environmental and Wastewater Treatment Plant Samples from Vietnam, The Philippines, and Myanmar. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2016; 70:671-681. [PMID: 26304512 DOI: 10.1007/s00244-015-0220-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Accepted: 08/10/2015] [Indexed: 06/04/2023]
Abstract
Water samples from Vietnam, The Philippines, and Myanmar were analyzed for artificial sweeteners (ASs) and iodinated X-ray contrast media (ICMs). High concentrations (low micrograms per liter) of ASs, including aspartame, saccharin, and sucralose, were found in wastewater treatment plant (WWTP) influents from Vietnam. Three ICMs, iohexol, iopamidol, and iopromide were detected in Vietnamese WWTP influents and effluents, suggesting that these ICMs are frequently used in Vietnam. ASs and ICMs were found in river water from downtown Hanoi at concentrations comparable to or lower than the concentrations in WWTP influents. The ASs and ICMs concentrations in WWTP influents and adjacent surface water significantly correlated (r (2) = 0.99, p < 0.001), suggesting that household wastewater is discharged directly into rivers in Vietnam. Acesulfame was frequently detected in northern Vietnamese groundwater, but the concentrations varied spatially by one order of magnitude even though the sampling points were very close together. This implies that poorly performing domestic septic tanks sporadically leak household wastewater into groundwater. High acesulfame, cyclamate, saccharin, and sucralose concentrations were found in surface water from Manila, The Philippines. The sucralose concentrations were one order of magnitude higher in the Manila samples than in the Vietnamese samples, indicating that more sucralose is used in The Philippines than in Vietnam. Acesulfame and cyclamate were found in surface water from Pathein (rural) and Yangon (urban) in Myanmar, but no ICMs were found in the samples. The ASs concentrations were two-three orders of magnitude lower in the samples from Myanmar than in the samples from Vietnam and The Philippines, suggesting that different amounts of ASs are used in these countries. We believe this is the first report of persistent ASs and ICMs having ubiquitous distributions in economically emerging South Asian countries.
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Affiliation(s)
- Yuta Watanabe
- Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto, 860-8555, Japan
| | - Leu Tho Bach
- Institute of Environmental Science and Engineering, National University of Civil Engineering (NUCE), 55 Giai Phong, Hanoi, Vietnam
| | - Pham Van Dinh
- Institute of Environmental Science and Engineering, National University of Civil Engineering (NUCE), 55 Giai Phong, Hanoi, Vietnam
| | - Maricar Prudente
- Science Education Department, De La Salle University, 2401 Taft Ave, Malate, Manila, 1004, Metro Manila, The Philippines
| | - Socorro Aguja
- De La Salle-Araneta University, Victoneta Compound, Malabon, Metro Manila, The Philippines
| | - Nyunt Phay
- Pathein University, Ayeyarwady Region, Pathein, Myanmar
| | - Haruhiko Nakata
- Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto, 860-8555, Japan.
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Anh TNQ, Harada H, Fujii S, Anh PN, Lieu PK, Tanaka S. Preliminary analysis of phosphorus flow in Hue Citadel. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2016; 73:69-77. [PMID: 26744936 DOI: 10.2166/wst.2015.463] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Characteristics of waste and wastewater management can affect material flows. Our research investigates the management of waste and wastewater in urban areas of developing countries and its effects on phosphorus flow based on a case study in Hue Citadel, Hue, Vietnam. One hundred households were interviewed to gain insight into domestic waste and wastewater management together with secondary data collection. Next, a phosphorus flow model was developed to quantify the phosphorus input and output in the area. The results showed that almost all wastewater generated in Hue Citadel was eventually discharged into water bodies and to the ground/groundwater. This led to most of the phosphorus output flowing into water bodies (41.2 kg P/(ha year)) and ground/groundwater (25.3 kg P/(ha year)). Sewage from the sewer system was the largest source of phosphorus loading into water bodies, while effluent from on-site sanitation systems was responsible for a major portion of phosphorus into the ground/groundwater. This elevated phosphorus loading is a serious issue in considering surface water and groundwater protection.
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Affiliation(s)
- T N Q Anh
- Graduate School of Global Environmental Studies, Kyoto University, Yoshida-honmachi, Sakyo, Kyoto 606-8501, Japan E-mail: ;
| | - H Harada
- Graduate School of Global Environmental Studies, Kyoto University, Yoshida-honmachi, Sakyo, Kyoto 606-8501, Japan E-mail: ;
| | - S Fujii
- Graduate School of Global Environmental Studies, Kyoto University, Yoshida-honmachi, Sakyo, Kyoto 606-8501, Japan E-mail: ;
| | - P N Anh
- Graduate School of Global Environmental Studies, Kyoto University, Yoshida-honmachi, Sakyo, Kyoto 606-8501, Japan E-mail: ;
| | - P K Lieu
- Department of Environmental Science, Hue University of Sciences, 77 Nguyen Hue, Hue City, Vietnam
| | - S Tanaka
- Graduate School of Global Environmental Studies, Kyoto University, Yoshida-honmachi, Sakyo, Kyoto 606-8501, Japan E-mail: ;
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Kuroda K, Nakada N, Hanamoto S, Inaba M, Katayama H, Do AT, Nga TTV, Oguma K, Hayashi T, Takizawa S. Pepper mild mottle virus as an indicator and a tracer of fecal pollution in water environments: comparative evaluation with wastewater-tracer pharmaceuticals in Hanoi, Vietnam. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 506-507:287-98. [PMID: 25460962 DOI: 10.1016/j.scitotenv.2014.11.021] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Revised: 10/31/2014] [Accepted: 11/04/2014] [Indexed: 04/14/2023]
Abstract
We analyzed pepper mild mottle virus (PMMoV) in 36 samples taken from surface water, wastewater, groundwater, tap water and bottled water in Hanoi, Vietnam. We then compared the occurrence and fates of PMMoV with pharmaceuticals and personal care products (PPCPs), which are known wastewater tracers. PMMoV was detected in 94% of the surface water samples (ponds, water from irrigated farmlands and rivers) and in all the wastewater samples. The PMMoV concentration ranged from 5.5×10(6)-7.2×10(6)copies/L in wastewater treatment plant (WWTP) influents, 6.5×10(5)-8.5×10(5)copies/L in WWTP effluents and 1.0×10(4)-1.8×10(6)copies/L in surface water. Among the sixty PPCPs analyzed, caffeine and carbamazepine had high detection rates in surface water (100% and 88%, respectively). In surface water, the concentration ratio of PMMoV to caffeine remained unchanged than that in WWTP influents, suggesting that the persistence of PMMoV in surface water was comparable to that of caffeine. The persistence and the large concentration ratio of PMMoV in WWTP influents to the method detection limit would account for its ubiquitous detection in surface water. In comparison, human enteric viruses (HEV) were less frequently detected (18-59%) than PMMoV in surface water, probably because of their faster decay. Together with the reported high human feces-specificity, our results suggested that PMMoV is useful as a sensitive fecal indicator for evaluating the potential occurrence of pathogenic viruses in surface water. Moreover, PMMoV can be useful as a moderately conservative fecal tracer for specifically tracking fecal pollution of surface water. PMMoV was detected in 38% of the groundwater samples at low concentrations (up to 19copies/L). PMMoV was not detected in the tap water and bottled water samples. In groundwater, tap water and bottled water samples, the occurrence of PPCPs and HEV disagreed with that of PMMoV, suggesting that PMMoV is not suitable as an indicator or a tracer in those waters.
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Affiliation(s)
- Keisuke Kuroda
- Department of Urban Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
| | - Norihide Nakada
- Research Center for Environmental Quality Management, Kyoto University, 1-2 Yumihama, Otsu City, Shiga 520-0811, Japan
| | - Seiya Hanamoto
- Research Center for Environmental Quality Management, Kyoto University, 1-2 Yumihama, Otsu City, Shiga 520-0811, Japan
| | - Manami Inaba
- Department of Urban Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Hiroyuki Katayama
- Department of Urban Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - An Thuan Do
- Department of Urban Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Tran Thi Viet Nga
- Institute of Environmental Science and Engineering, National University of Civil Engineering, 55 Giai Phong, Hanoi, Viet Nam
| | - Kumiko Oguma
- Department of Urban Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Takeshi Hayashi
- Faculty of Education and Human Studies, Akita University, 1-1 Tegata-gakuen-machi, Akita City, Akita 010-8502, Japan
| | - Satoshi Takizawa
- Department of Urban Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
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Yen-Phi VT, Rechenburg A, Vinneras B, Clemens J, Kistemann T. Pathogens in septage in Vietnam. THE SCIENCE OF THE TOTAL ENVIRONMENT 2010; 408:2050-3. [PMID: 20138647 DOI: 10.1016/j.scitotenv.2010.01.030] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2009] [Revised: 01/13/2010] [Accepted: 01/18/2010] [Indexed: 05/24/2023]
Abstract
Septage is widely acknowledged as a major source of infectious pathogens while disposal of septage, and the operation and maintenance of septic tanks, is not regulated in many developing countries. Twenty untreated septage and septage sludge samples were taken from Can Tho City, Vietnam to examine their pathogen content, and indicator micro-organisms. Escherichia coli and Enterococcus spp. were detected in all samples, regardless of sludge storage time. Phages were detected in 80% of samples. Salmonella spp. were detected in 70% of the untreated septage and 60% of septage sludge samples. Concentrations of phages and bacteria tested in septage sludge after many years of tank storage were much higher than the expected levels. Helminth ova were present in 95% of untreated septage samples with an average of 450 oval(-1), and were detected in all septage sludge samples with an average of 16,000 oval(-1). Twelve varieties of helminth ova were identified. More helminth ova varieties in higher concentrations were found in septage than those reported from stool samples. The varieties' frequency ranged from 10% to 50% and Ascaris lumbricoides predominated. Results show that pathogens and indicator micro-organisms, especially helminth ova, accumulate in sludge. Thus helminth ova should be considered when septage sludge is treated and used for agriculture. Proper health protection measures must be applied for people handling septage.
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Affiliation(s)
- Vo Thi Yen-Phi
- Institute for Hygiene and Public Health, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn, Germany.
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