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Cao NDT, Vo DHT, Pham MDT, Nguyen VT, Nguyen TB, Le LT, Mukhtar H, Nguyen HV, Visvanathan C, Bui XT. Microplastics contamination in water supply system and treatment processes. Sci Total Environ 2024; 926:171793. [PMID: 38513854 DOI: 10.1016/j.scitotenv.2024.171793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 12/30/2023] [Revised: 03/04/2024] [Accepted: 03/16/2024] [Indexed: 03/23/2024]
Abstract
Due to global demand, millions of tons of plastics have been widely consumed, resulting in the widespread entry of vast amounts of microplastic particles into the environment. The presence of microplastics (MPs) in water supplies, including bottled water, has undergone systematic review, assessing the potential impacts of MPs on humans through exposure assessment. The main challenges associated with current technologies lie in their ability to effectively treat and completely remove MPs from drinking and supply water. While the risks posed by MPs upon entering the human body have not yet been fully revealed, there is a predicted certainty of negative impacts. This review encompasses a range of current technologies, spanning from basic to advanced treatments and varying in scale. However, given the frequent detection of MPs in drinking and bottled water, it becomes imperative to implement comprehensive management strategies to address this issue effectively. Consequently, integrating current technologies with management options such as life-cycle assessment, circular economy principles, and machine learning is crucial to eliminating this pervasive problem.
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Affiliation(s)
- Ngoc-Dan-Thanh Cao
- Ho Chi Minh City University of Technology (HCMUT), 268 Ly Thuong Kiet Street, District 10, Ho Chi Minh City, Viet Nam; Vietnam National University Ho Chi Minh (VNU-HCM), Linh Trung ward, Ho Chi Minh City 700000, Viet Nam
| | - Dieu-Hien Thi Vo
- Institute of Applied Technology and Sustainable Development, Nguyen Tat Thanh University, Ho Chi Minh City 700000, Viet Nam
| | - Mai-Duy-Thong Pham
- Ho Chi Minh City University of Technology (HCMUT), 268 Ly Thuong Kiet Street, District 10, Ho Chi Minh City, Viet Nam; Vietnam National University Ho Chi Minh (VNU-HCM), Linh Trung ward, Ho Chi Minh City 700000, Viet Nam
| | - Van-Truc Nguyen
- Faculty of Environment, Saigon University, Ho Chi Minh City 700000, Viet Nam
| | - Thanh-Binh Nguyen
- College of Hydrosphere Science, National Kaohsiung University of Science and Technology, No. 142, Haijhuan Road, Nanzih District, Kaohsiung City 81157, Taiwan
| | - Linh-Thy Le
- Department of Environmental Health, Faculty of Public Health, University of Medicine and Pharmacy at Ho Chi Minh City (UMP HCMC), 217 Hong Bang street, District 5th, Ho Chi Minh City, Viet Nam
| | - Hussnain Mukhtar
- Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, NE, 68583, USA
| | - Huu-Viet Nguyen
- Ho Chi Minh City University of Technology (HCMUT), 268 Ly Thuong Kiet Street, District 10, Ho Chi Minh City, Viet Nam; Vietnam National University Ho Chi Minh (VNU-HCM), Linh Trung ward, Ho Chi Minh City 700000, Viet Nam
| | - Chettiyappan Visvanathan
- Department of Civil and Environmental Engineering, Mahidol University, Salaya, Nakhon Pathom, Thailand
| | - Xuan-Thanh Bui
- Ho Chi Minh City University of Technology (HCMUT), 268 Ly Thuong Kiet Street, District 10, Ho Chi Minh City, Viet Nam; Vietnam National University Ho Chi Minh (VNU-HCM), Linh Trung ward, Ho Chi Minh City 700000, Viet Nam.
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2
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Le TS, Bui XT, Nguyen PD, Hao Ngo H, Dang BT, Le Quang DT, Thi Pham T, Visvanathan C, Diels L. Bacterial community composition in a two-stage anaerobic membrane bioreactor for co-digestion of food waste and food court wastewater. Bioresour Technol 2024; 391:129925. [PMID: 37898371 DOI: 10.1016/j.biortech.2023.129925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 08/04/2023] [Revised: 10/24/2023] [Accepted: 10/24/2023] [Indexed: 10/30/2023]
Abstract
This study investigated the microbial community of a two-stage anaerobic membrane bioreactor (2S-AnMBR) co-digesting food waste and food court wastewater. The hydrolysis reactor (HR) was dominated by Bacteroidetes and Firmicutes phylum, with genus Lactobacillus enriched due to food waste fermentation. The up-flow anaerobic sludge blanket (UASB) was dominated by genus such as Methanobacterium and Methanosaeta. The presence of Methanobacterium (91 %) and Methanosaeta (7.5 %) suggested that methane production pathways inevitably undergo both hydrogenotrophic and acetoclastic methanogenesis. Hydrogen generated during hydrolysis fermentation in the HR contributed to methane production in the UASB via hydrogenotrophic pathways. However, the low abundance of Methanosaeta in the UASB can be attributed to the limited inffluent of volatile fatty acids (VFA) and the competitive presence of acetate-consuming bacteria Acinetobacter. The UASB exhibited more excellent dispersion and diversity of metabolic pathways compared to the HR, indicating efficient methane production.
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Affiliation(s)
- Thanh-Son Le
- Ho Chi Minh City University of Technology (HCMUT), 268 Ly Thuong Kiet Street, District 10, Ho Chi Minh City, Viet Nam; Vietnam National University Ho Chi Minh City (VNU-HCM), Linh Trung ward, Ho Chi Minh City 700000, Viet Nam; Institute for Environment and Natural Resources, 142 To Hien Thanh street, District 10, Ho Chi Minh City, Viet Nam
| | - Xuan-Thanh Bui
- Ho Chi Minh City University of Technology (HCMUT), 268 Ly Thuong Kiet Street, District 10, Ho Chi Minh City, Viet Nam; Vietnam National University Ho Chi Minh City (VNU-HCM), Linh Trung ward, Ho Chi Minh City 700000, Viet Nam
| | - Phuoc-Dan Nguyen
- Ho Chi Minh City University of Technology (HCMUT), 268 Ly Thuong Kiet Street, District 10, Ho Chi Minh City, Viet Nam; Vietnam National University Ho Chi Minh City (VNU-HCM), Linh Trung ward, Ho Chi Minh City 700000, Viet Nam.
| | - Huu Hao Ngo
- School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NSW 2007, Australia.
| | - Bao-Trong Dang
- Ho Chi Minh City University of Technology (HCMUT), 268 Ly Thuong Kiet Street, District 10, Ho Chi Minh City, Viet Nam; Vietnam National University Ho Chi Minh City (VNU-HCM), Linh Trung ward, Ho Chi Minh City 700000, Viet Nam
| | - Do-Thanh Le Quang
- Ho Chi Minh City University of Technology (HCMUT), 268 Ly Thuong Kiet Street, District 10, Ho Chi Minh City, Viet Nam; Vietnam National University Ho Chi Minh City (VNU-HCM), Linh Trung ward, Ho Chi Minh City 700000, Viet Nam
| | - Tan Thi Pham
- Ho Chi Minh City University of Technology (HCMUT), 268 Ly Thuong Kiet Street, District 10, Ho Chi Minh City, Viet Nam; Vietnam National University Ho Chi Minh City (VNU-HCM), Linh Trung ward, Ho Chi Minh City 700000, Viet Nam
| | - Chettiyappan Visvanathan
- Department of Civil and Environmental Engineering, Mahidol University, Salaya, Nakhon Pathom, Thailand
| | - Ludo Diels
- University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen, Belgium
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3
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Hashmi SI, Hewage HTSA, Visvanathan C. Cleaner production auditing for plastic recycling industry in Pakistan: A baseline study. Chemosphere 2023:139338. [PMID: 37399996 DOI: 10.1016/j.chemosphere.2023.139338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 06/20/2023] [Accepted: 06/24/2023] [Indexed: 07/05/2023]
Abstract
Recycling plastics is a good alternative to manage the plastic waste generated in Pakistan. Unfortunately, the country lacks efficient system to manage or recycle the plastic waste it generates. Lack of government support, absence of standard operating procedures, negligence towards health and safety of workers, increasing costs of raw materials and poor quality of the recyclates are some of the issues currently faced by plastic recyclers in Pakistan. Considering the need of cleaner production audits in plastic recycling industries, this study was carried out to establish an initial reference benchmark. Production processes in 10 recycling industries were evaluated from cleaner production perspective. The study showed the average water consumption of a recycling industry as high as 3315 L/ton. All the consumed water is wasted in the nearby community sewer while, only 3 recyclers recycled between 70 and 75% the treated wastewater. In addition, a recycling facility on an average consumed 172.5 kWh of power for processing 1 ton of plastic waste. The average temperature was observed to be 36.5 °C and noise levels exceeded the permissible limits. Moreover, the industry is male-dominated, workers are mostly underpaid and have no access to good healthcare facilities. Recyclers lack standardization and have no national guidelines to follow. Guidelines and standardization of recycling process, wastewater treatment, use of renewable energy, water reuse etc, are direly needed for uplifting this sector and reducing its impacts on the environment.
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Affiliation(s)
- Safeerul Islam Hashmi
- Institute of Environmental Sciences and Engineering, School of Civil and Environmental Engineering, National University of Science and Technology, 24090, Scholar Avenue, Sector H-12, Islamabad, Pakistan
| | - Harshi Tharangika Sirisena Aluthduwe Hewage
- Department of Energy, Environment and Climate Change, School of Environment, Resources, and Development, Asian Institute of Technology, PO Box 4, Klong Luang, Pathum Thani, 12120, Thailand
| | - Chettiyappan Visvanathan
- Department of Energy, Environment and Climate Change, School of Environment, Resources, and Development, Asian Institute of Technology, PO Box 4, Klong Luang, Pathum Thani, 12120, Thailand.
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Zhang W, Xue W, Xiao K, Visvanathan C, Tang J, Li L. Selection and optimization of carbon-based electrode materials for flow-electrode capacitive deionization. Sep Purif Technol 2023. [DOI: 10.1016/j.seppur.2023.123649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
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Phosirikul N, Visvanathan C, Rene ER. Removal of gas phase methanol and acetonitrile mixture in an air membrane bioreactor (aMBR) under steady and transient-state operations. Bioresour Technol 2023; 376:128824. [PMID: 36871697 DOI: 10.1016/j.biortech.2023.128824] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [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: 01/31/2023] [Revised: 02/25/2023] [Accepted: 02/28/2023] [Indexed: 06/18/2023]
Abstract
A laboratory scale air membrane bioreactor (aMBR) was used to treat a gas-phase mixture of methanol (MeOH) and acetonitrile (ACN), with an inoculum comprising of a mixed culture of microorganisms. The aMBR was tested under both steady-state and transient modes, with inlet concentrations ranging from 1 to 50 g/m3 for both compounds. Under steady-state conditions, the aMBR was operated at various empty bed residence times (EBRT) and MeOH:ACN ratios, while intermittent shutdown was tested during transient-state operations. The results showed that, the aMBR demonstrated > 80% removal efficiencies for both MeOH and ACN. An EBRT of 30 s was found to be the best treatment time for the mixture, providing>98% removal, with<20 mg/L of the pollutant accumulation in the liquid-phase. The microorganisms also showed preferential utilization of ACN compared to MeOH from the gas-phase and good resilience capacity after three days of shutdown/re-start operation.
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Affiliation(s)
- Nichakul Phosirikul
- Department of Energy, Environment and Climate Change, School of Environment, Resources and Development, Asian Institute of Technology, P. O. Box 4, Khlong Luang, Pathumthani 12120, Thailand
| | - Chettiyappan Visvanathan
- Department of Energy, Environment and Climate Change, School of Environment, Resources and Development, Asian Institute of Technology, P. O. Box 4, Khlong Luang, Pathumthani 12120, Thailand
| | - Eldon R Rene
- Department of Water Supply, Sanitation and Environmental Engineering, IHE Delft Institute for Water Education, Westvest 7, 2601DA Delft, the Netherlands.
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Thant KJW, Anh-Vu N, Yun-Je K, Masumi K, Visvanathan C. Performance of pilot-scale membrane aerated biofilm reactors integrated with anoxic nano-biotechnological reactor for domestic wastewater treatment. Chemosphere 2023; 319:137927. [PMID: 36716932 DOI: 10.1016/j.chemosphere.2023.137927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 11/11/2022] [Revised: 01/12/2023] [Accepted: 01/18/2023] [Indexed: 06/18/2023]
Abstract
Membrane-aerated biofilm reactors (MABRs) have aroused increasing attention due to their excellent performance in treating wastewater, where the membranes behave as bio-carriers for microorganisms and bubbleless air diffusers. The MABR technology has not been fully commercialized due to reactor design and low total nitrogen (TN) removal efficiency at short hydraulic retention times (HRT). In this study, a hybrid system of MABR 1 integrated with an anoxic nano-biotechnological reactor filled with Granulated Nanoscale Oxyhydroxides of Fe (GNOF) media was evaluated to assess the improvement in nitrogen removal performance at 12, 10, and 4 h of HRTs. At the same time, another MABR (MABR 2) was operated individually at 12, 10, 8, 6, 4, and 2 h of HRTs to assess the influence of HRT on nitrogen removal performance. An enhancement in removal performance was reported in the hybrid MABR-GNOF, achieving the highest removal efficiencies of 74.3 ± 3.1% for ammonium nitrogen (NH4+-N), 69.8 ± 2.1% for total nitrogen (TN), and 90.9 ± 1.7% for chemical oxygen demand (COD), at 12 h HRT. The hybrid MABR-GNOF system attained 18% higher nitrogen removal than the MABR-only system at 12 h of HRT. A simultaneous anoxic nitrification-denitrification and COD oxidation might be developed for the removal of COD, NH4+-N, and TN from domestic wastewater by using GNOF as an electron acceptor in the hybrid MABR-GNOF unit. The findings in this study confirmed the possibility of integration of GNOF and MABR on a pilot scale and are promising for the application of this hybrid system on a full scale.
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Affiliation(s)
- Khin July Win Thant
- Department of Energy, Environment and Climate Change, School of Environment, Resources and Development, Asian Institute of Technology, P.O. Box 4, Khlong Luang, Pathumthani, 12120, Thailand
| | - Nguyen Anh-Vu
- Department of Energy, Environment and Climate Change, School of Environment, Resources and Development, Asian Institute of Technology, P.O. Box 4, Khlong Luang, Pathumthani, 12120, Thailand
| | - Kigo Yun-Je
- Aqua Solutions Laboratory, Mitsubishi Chemical Corporation, 1-2, Ushikawadori 4-chome, Toyohashi-shi, Aichi, 440-8601, Japan
| | - Kobayashi Masumi
- Technology Section, Performance Separation Materials Unit, Aqua and Infrastructure Sector, Mitsubishi Chemical Corporation, 10th Floor, Gate City Ohsaki East Tower, 11-2, Osaki 1-chome, Shinagawa-ku, Tokyo, 141-0032, Japan
| | - Chettiyappan Visvanathan
- Department of Energy, Environment and Climate Change, School of Environment, Resources and Development, Asian Institute of Technology, P.O. Box 4, Khlong Luang, Pathumthani, 12120, Thailand.
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Anh-Vu N, Yun-Je L, Masumi K, Visvanathan C. Effects of membrane relaxation rate on performance of pilot-scale membrane aerated biofilm reactors treating domestic wastewater. Environ Res 2022; 211:113003. [PMID: 35227677 DOI: 10.1016/j.envres.2022.113003] [Citation(s) in RCA: 1] [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: 10/28/2021] [Revised: 02/13/2022] [Accepted: 02/20/2022] [Indexed: 06/14/2023]
Abstract
The membranes of a Membrane Aerated Biofilm Reactor (MABR) function as bubble-less air diffusers and bio-carriers. Recent bench-scale experiments reported that the shape of membranes influenced the oxygen transfer and utilization rates, which in turn affected the pollutant removal performance of the MABR. In this study, two pilot-scale MABRs using multi-layer hollow fiber membranes with the relaxation rates of 0.1-1.8% (MABR 1) and 1.0-2.8% (MABR 2) were used for the treatment of organics and nitrogen in real medium-strength domestic wastewater. Higher-relaxation-rate membranes have loose and more curved fiber bunch that may allow biofilm to grow more easily and let air diffuse more efficiently. MABR 2 had achieved better performance than MABR 1 at 12- and 6-h Hydraulic Retention Time (HRT), with respectively 0.7-4.3%, 17.7-18.1%, and 5.5-9.0% higher removal efficiencies for Chemical Oxygen Demand (COD), Ammonia Nitrogen (NH4+), and Total Nitrogen (TN). The highest COD, NH4+, and TN removal efficiencies were 94.7%, 81.1%, and 57.1%, respectively, at 12 h HRT in MABR 2. The addition of Polyvinyl Alcohol (PVA) gel beads carrying denitrifying bacteria had enhanced the denitrification in both the reactors. Increments of 5.0-9.0% and 6.6-12.3% were reported for TN removal efficiencies of MABR 1 and 2 combined with PVA gel, sequentially.
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Affiliation(s)
- Nguyen Anh-Vu
- Department of Energy, Environment and Climate Change, School of Environment, Resources and Development, Asian Institute of Technology, P.O. Box 4, Khlong Luang, Pathumthani, 12120, Thailand.
| | - Lee Yun-Je
- Aqua Solutions Laboratory, Mitsubishi Chemical Corporation, 1-2, Ushikawadori 4-chome, Toyohashi-shi, Aichi, 440-8601, Japan.
| | - Kobayashi Masumi
- Technology Section, Performance Separation Materials Unit, Aqua and Infrastructure Sector, Mitsubishi Chemical Corporation, 10th Floor, Gate City Ohsaki East Tower, 11-2, Osaki 1-chome, Shinagawa-ku, Tokyo, 141-0032, Japan.
| | - Chettiyappan Visvanathan
- Department of Energy, Environment and Climate Change, School of Environment, Resources and Development, Asian Institute of Technology, P.O. Box 4, Khlong Luang, Pathumthani, 12120, Thailand.
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Hanvajanawong K, Suyamud B, Suwannasilp BB, Lohwacharin J, Visvanathan C. Unravelling capability of two-stage thermophilic anaerobic membrane bioreactors for high organic loading wastewater: Effect of support media addition and irreversible fouling. Bioresour Technol 2022; 348:126725. [PMID: 35131463 DOI: 10.1016/j.biortech.2022.126725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 11/29/2021] [Revised: 01/11/2022] [Accepted: 01/13/2022] [Indexed: 06/14/2023]
Abstract
This study investigated the effects of adding polyvinyl alcohol (PVA) beads on the performance of methanogenic reactors and the fouling behavior of a two-stage thermophilic anaerobic membrane bioreactor (ThAnMBR) for treating wastewater at a feed chemical oxygen demand (COD) of 10 g/L. The PVA-added methanogenic reactor exhibited stable operation performance and offered a relatively low volatile fatty acid concentration effluent with a higher COD removal than the system without PVA addition. The predominant microbial communities in both methanogenic reactors were similar and were assigned to the genus Methanosaeta, followed by Clostridia, which was the predominant genus in the hydrolytic reactor. Ultrafiltration in the PVA-added system offered higher effluent quality and lower fouling resistance. The system was able to operate with hydraulically removable fouling, without any chemical cleaning requirements; however, an elevated flux caused the system to suffer from hydraulically irreversible fouling. PVA beads exhibit their structural stability over long-term operation.
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Affiliation(s)
- K Hanvajanawong
- Department of Environmental Engineering, Faculty of Engineering, Chulalongkorn University, 254 Phayathai Road, Pathumwan, Bangkok 10330, Thailand
| | - B Suyamud
- Department of Environmental Engineering, Faculty of Engineering, Chulalongkorn University, 254 Phayathai Road, Pathumwan, Bangkok 10330, Thailand
| | - B B Suwannasilp
- Department of Environmental Engineering, Faculty of Engineering, Chulalongkorn University, 254 Phayathai Road, Pathumwan, Bangkok 10330, Thailand; Research Network NANOTEC - CU on Environment, Department of Environmental Engineering, Chulalongkorn University, Thailand
| | - J Lohwacharin
- Department of Environmental Engineering, Faculty of Engineering, Chulalongkorn University, 254 Phayathai Road, Pathumwan, Bangkok 10330, Thailand; Research Network NANOTEC - CU on Environment, Department of Environmental Engineering, Chulalongkorn University, Thailand; Professor Aroon Sorathesn Center of Excellence in Environmental Engineering, Department of Environmental Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok 10330, Thailand.
| | - C Visvanathan
- School of Environment, Resources and Development, Asian Institute of Technology, Pathumthani, Thailand
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Dang BT, Nguyen TT, Bui XT, Hao Ngo H, Andrew Lin KY, Tomoaki I, Saunders T, Huynh TN, Ngoc-Dan Cao T, Visvanathan C, Varjani S, Rene ER. Non-submerged attached growth process for domestic wastewater treatment: Influence of media types and internal recirculation ratios. Bioresour Technol 2022; 343:126125. [PMID: 34653623 DOI: 10.1016/j.biortech.2021.126125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 08/22/2021] [Revised: 10/07/2021] [Accepted: 10/09/2021] [Indexed: 06/13/2023]
Abstract
This study is aimed to comprehend the treatment of non-submerged attached growth systems using bio-sponge, bio-cord, and bio-cloth media. Three reactors were set up with internal recirculation ratio of 1 (IR = 1) and similar media surface area. Bio-sponge and bio-cloth reactors showed removal of COD (79 vs. 76%) and NH4+-N (78 vs. 73%). While bio-cord treatment was deteriorated due to time-dependent process. Multiple linear regression revealed that alkalinity governed the formation degree of the anaerobic zone in bio-sponges, partially affecting nitrification. Increasing IR from 1 to 3 caused sloughing of the attached biomass and was positively correlated with effluent nitrite nitrogen concentration, indicating the sensitivity of nitrification to spatial distribution effects. In addition, bio-sponge system obtained superior performance at IR of 2 while bio-cloth one might be also an effective media for wastewater treatment if having good durability.
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Affiliation(s)
- Bao-Trong Dang
- Ho Chi Minh City University of Technology (HUTECH), 475A Dien Bien Phu, Ward 25, Binh Thanh District, Ho Chi Minh City, Viet Nam
| | - Thanh-Tin Nguyen
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology, 123 Cheomdangwagi-ro, Buk-gu, Gwangju 61005, Republic of Korea; Key Laboratory of Advanced Waste Treatment Technology, Ho Chi Minh City University of Technology (HCMUT), Vietnam National University Ho Chi Minh (VNU-HCM), Thu Duc City, Viet Nam
| | - Xuan-Thanh Bui
- Key Laboratory of Advanced Waste Treatment Technology, Ho Chi Minh City University of Technology (HCMUT), Vietnam National University Ho Chi Minh (VNU-HCM), Thu Duc City, Viet Nam; Faculty of Environment and Natural Resources, Ho Chi Minh City University of Technology (HCMUT), 268 Ly Thuong Kiet Str., District 10, Ho Chi Minh City 700000, Viet Nam.
| | - Huu Hao Ngo
- School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NWS 2007, Australia
| | - Kun-Yi Andrew Lin
- Department of Environmental Engineering & Innovation and Development Center of Sustainable Agriculture, National Chung Hsing University, 250 Kuo-Kuang Road, Taichung, Taiwan
| | - Itayama Tomoaki
- Graduate School of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan
| | - Todd Saunders
- Graduate School of Biomedical Science, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan
| | - Tan-Nhut Huynh
- Key Laboratory of Advanced Waste Treatment Technology, Ho Chi Minh City University of Technology (HCMUT), Vietnam National University Ho Chi Minh (VNU-HCM), Thu Duc City, Viet Nam; Faculty of Environment and Natural Resources, Ho Chi Minh City University of Technology (HCMUT), 268 Ly Thuong Kiet Str., District 10, Ho Chi Minh City 700000, Viet Nam
| | - Thanh Ngoc-Dan Cao
- Key Laboratory of Advanced Waste Treatment Technology, Ho Chi Minh City University of Technology (HCMUT), Vietnam National University Ho Chi Minh (VNU-HCM), Thu Duc City, Viet Nam
| | - Chettiyappan Visvanathan
- Department of Energy, Environment and Climate Change, School of Environment, Resources and Development, Asian Institute of Technology, P.O. Box 4, Klong Luang, Pathumthani 12120, Thailand
| | - Sunita Varjani
- Gujarat Pollution Control Board, Gandhinagar, Gujarat 382010, India
| | - Eldon R Rene
- Department of Environmental Engineering and Water Technology, IHE - Delft, Institute of Water Education, 2601 DA, Delft, The Netherlands
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Kanojia A, Visvanathan C. Assessment of urban solid waste management systems for Industry 4.0 technology interventions and the circular economy. Waste Manag Res 2021; 39:1414-1426. [PMID: 33899620 DOI: 10.1177/0734242x21992424] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The ongoing fourth industrial revolution, Industry 4.0 (I4.0), is transforming various industries across the globe. At the same time, resource scarcity with high consumption rates has led to the development of the circular economy. Both concepts advocate for sustainable growth and waste minimization. In developing countries, the integrated solid waste management framework is undergoing modification under I4.0 and the circular economy. Urban local bodies are often unable to measure the readiness of their waste management systems to transform under I4.0 and the circular economy. Here the novel concept of Waste 4.0 is developed. 'Waste 4.0' is a readiness assessment tool to promote the comprehensive transformation of municipal solid waste management under I4.0 and circular economy. This tool has eight determinants for assessing the municipal solid waste management of urban local bodies. To validate Waste 4.0 the urban local bodies of Indore and Sagar, India were used as case studies. The readiness index for I4.0 in the municipal solid waste management system in Indore and Sagar was 0.72 and 0.14, respectively. The readiness index for circular economy focus in Indore and Sagar was 0.65 and 0.13, respectively. The Indore urban local body was classified as an 'Experienced' player for I4.0 Intervention and a 'circular economy fast adopter' for circular economy focus under I4.0 readiness. The Sagar urban local body was classified as a 'Hesitator' player for I4.0 Intervention and achieved the 'Business as usual' tag for circular economy focus under I4.0 readiness. With the Waste 4.0 assessment results urban local bodies can better plan and thus transform their municipal solid waste management systems under I4.0 and the circular economy.
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Affiliation(s)
- Abhishek Kanojia
- Department of Energy, Environment and Climate Change, Asian Institute of Technology, Thailand
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Li L, Phungsai P, Kurisu F, Visvanathan C. Orbitrap mass spectrometry for the molecular characterization of water resource recovery from polluted surface water using membrane bioreactor. Chemosphere 2021; 270:128771. [PMID: 33131732 DOI: 10.1016/j.chemosphere.2020.128771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 07/15/2020] [Revised: 10/19/2020] [Accepted: 10/26/2020] [Indexed: 06/11/2023]
Abstract
The increasing organic contamination of surface water hinders the conventional tap water treatment process. Membrane bioreactors (MBRs) are a promising alternative technology for recovering water from polluted surface water. In this study, the composition changes of dissolved organic matters (DOMs) in MBR and ultraviolet/ozone (UV/O3)-MBR systems for polluted surface water treatment were investigated using Orbitrap mass spectrometry analysis with unknown screening. The intense DOM ions within a mass-to-charge ratio range of 100-500 was detected, and 2340 molecular formulae from 5743 peaks were assigned to the two systems. The most abundant components were formulae with C, H, O, N, and CHO only classes. The highest formulae decrease including CHO, CHON, CHOS, and CHONS were attributed to the bio-carrier used in both systems. Results showed that bioprocess was the main contributor in the DOM reduction, and the integration of UV/O3 into the MBR improved the DOM composition changes. Biodegradable components with low O/C ratio in the CHO and CHON classes remarkably increased in the UV/O3-MBR system. The integration of UV/O3 as a polishing step in the recirculation stream of MBR system was effective in improve the DOM removal.
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Affiliation(s)
- Lu Li
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China; School of Environment, Resources and Development, Asian Institute of Technology, Pathumthani, 12120, Thailand; Department of Urban Engineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656, Japan.
| | - Phanwatt Phungsai
- Department of Environmental Engineering, Faculty of Engineering and Research Center for Environmental and Hazardous Substance Management, Khon Kaen University, Khon Kaen, 40002, Thailand
| | - Futoshi Kurisu
- Research Center for Water Environment Technology, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo, 113-8656, Japan
| | - C Visvanathan
- School of Environment, Resources and Development, Asian Institute of Technology, Pathumthani, 12120, Thailand
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Udomkittayachai N, Xue W, Xiao K, Visvanathan C, Tabucanon AS. Electroconductive moving bed membrane bioreactor (EcMB-MBR) for single-step decentralized wastewater treatment: Performance, mechanisms, and cost. Water Res 2021; 188:116547. [PMID: 33126002 DOI: 10.1016/j.watres.2020.116547] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [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: 08/02/2020] [Revised: 10/08/2020] [Accepted: 10/20/2020] [Indexed: 06/11/2023]
Abstract
Membrane bioreactor (MBR) is an advantageous technology for wastewater treatment. However, efficient nutrient removal and membrane fouling mitigation remain major challenges in its applications. In this study, an electroconductive moving bed membrane bioreactor (EcMB-MBR) was proposed for simultaneous removal of organics and nutrients from domestic wastewater. The EcMB-MBR was composed of a submerged MBR, filled with electrodes and free-floating conductive media. Conductive media were introduced to reduce energy consumption in an electrochemical MBR, to improve nitrogen removal, and to mitigate membrane fouling. The results showed that COD, total nitrogen, and total phosphorus removal was up to 97.1 ± 1.4%, 88.8 ± 4.2%, and 99.0 ± 0.9%, respectively, in comparison with those of 93.4 ± 1.5%, 65.2 ± 5.3%, and 20.4 ± 11.3% in a conventional submerged MBR. Meanwhile, a total membrane resistance reduction of 26.7% was obtained in the EcMB-MBR. The optimized operating condition was determined at an intermittent electricity exposure time of 10 min-ON/10 min-OFF, and a direct current density of 15 A/m2. The interactions between electric current and conductive media were explored to understand the working mechanism in this proposed system. The conductive media reduced 21% of the electrical resistivity in the mixed liquor at a selected packing density of 0.20 (v/v). The combination of electrochemical process and conductive media specially enhanced the reduction of nitrate-nitrogen (NO3--N) through hybrid bio-electrochemical denitrification processes. These mechanisms involved with electrochemically assisted autotrophic denitrification by autotrophic denitrifying bacteria. As a result, 5.2% of NO3--N remained in the effluent of EcMB-MBR in comparison with that of 29.5% in the MBR. Membrane fouling was minimized via both mechanical scouring and electrochemical decomposition/precipitation of organic/particulate foulants. Furthermore, a preliminary cost analysis indicated that an additional operating cost of 0.081 USD/m3, accounting for 10 - 30% increment of the operating cost of a conventional MBR, was needed to enhance the nitrogen and phosphorus removal correspondingly in the EcMB-MBR.
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Affiliation(s)
- Nutkritta Udomkittayachai
- Department of Energy, Environment and Climate Change, School of Environment, Resources and Development, Asian Institute of Technology, P.O. Box 4, Klong Luang, Pathumthani 12120, Thailand
| | - Wenchao Xue
- Department of Energy, Environment and Climate Change, School of Environment, Resources and Development, Asian Institute of Technology, P.O. Box 4, Klong Luang, Pathumthani 12120, Thailand.
| | - Kang Xiao
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chettiyappan Visvanathan
- Department of Energy, Environment and Climate Change, School of Environment, Resources and Development, Asian Institute of Technology, P.O. Box 4, Klong Luang, Pathumthani 12120, Thailand
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Prikyai K, Watsuntorn W, Rene ER, Visvanathan C. Performance of an air membrane bioreactor for methanol removal under steady and transient state conditions. Chemosphere 2020; 260:127514. [PMID: 32688309 DOI: 10.1016/j.chemosphere.2020.127514] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [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: 04/10/2020] [Revised: 06/10/2020] [Accepted: 06/18/2020] [Indexed: 06/11/2023]
Abstract
The main aim of this study was to evaluate the performance of an air membrane bioreactor (aMBR) for the treatment of gas-phase methanol. A laboratory-scale hollow fiber aMBR was operated for 150 days, at inlet methanol concentrations varying between 2 and 30 g m-3 and at empty bed residence times (EBRT) of 30, 10 and 5 s. Under steady-state conditions, a maximum methanol removal efficiency (RE) of 98% was obtained at an EBRT of 30 s and a decrease in RE of methanol was observed at lower EBRTs. On increasing the inlet loading rate, some portion of gas-phase MeOH was stripped into the liquid phase due to its solubility in water. Under transient conditions, the MeOH removal efficiency dropped from an average value of 95%-90% after 5 h of 10-fold shock load and dropped from an average value of 95%-88% under 5-fold increase in shock load. During transient-state tests, the aMBR performed well under different upset loading conditions and a drop in RE of ∼ 5-10% was observed. However, the aMBR performance was restored within 1-2 days when pre-shock conditions were restored. The results from microbial structure analysis revealed a big shift of the dominant methanol degrader, from Candida boidinii strain TBRC 217 to Xanthobacter sp. and Fusicolla sp., respectively.
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Affiliation(s)
- Kamonkarn Prikyai
- Department of Energy, Environment and Climate Change, School of Environmental, Resources and Development, Asian Institute of Technology, Pathumthani, Thailand
| | - Wannapawn Watsuntorn
- Program in Biotechnology, Faculty of Science, Chulalongkorn University, Bangkok, Thailand
| | - Eldon R Rene
- Department of Environmental Engineering and Water Technology, IHE Delft Institute for Water Education, PO Box 3015, 2601 DA, Delft, the Netherlands.
| | - Chettiyappan Visvanathan
- Department of Energy, Environment and Climate Change, School of Environmental, Resources and Development, Asian Institute of Technology, Pathumthani, Thailand
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Rene ER, Chiemchaisri C, Jegatheesan JV, Visvanathan C, Shu L. Preface to the CESE 2018 special issue: Environmental technologies for pollution prevention and waste treatment. J Environ Manage 2020; 265:110585. [PMID: 32421566 DOI: 10.1016/j.jenvman.2020.110585] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Affiliation(s)
- Eldon R Rene
- IHE Delft Institute for Water Education, Water Supply, Sanitation and Environmental Engineering, 2601, DA, Delft, the Netherlands.
| | - Chart Chiemchaisri
- Department of Environmental Engineering, Kasetsart University, 50 Phaholyothin Rd., Ladyao, Jatujak, Bangkok, 10900, Thailand
| | | | - Chettiyappan Visvanathan
- Environmental Engineering and Management Program, School of Environment, Resources and Development, Asian Institute of Technology, P.O. Box 4, Klong Luang, Pathumthani, 12120, Thailand
| | - Li Shu
- LJS Environment, 2 Parkville Avenue, Parkville, VIC, 3052, Melbourne, Australia
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Sharma A, Aloysius V, Visvanathan C. Recovery of plastics from dumpsites and landfills to prevent marine plastic pollution in Thailand. ACTA ACUST UNITED AC 2020. [DOI: 10.1007/s42768-019-00027-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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16
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Li L, Geng S, Wu C, Song K, Sun F, Visvanathan C, Xie F, Wang Q. Microplastics contamination in different trophic state lakes along the middle and lower reaches of Yangtze River Basin. Environ Pollut 2019; 254:112951. [PMID: 31374488 DOI: 10.1016/j.envpol.2019.07.119] [Citation(s) in RCA: 79] [Impact Index Per Article: 15.8] [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: 06/04/2019] [Revised: 07/22/2019] [Accepted: 07/23/2019] [Indexed: 05/24/2023]
Abstract
Microplastics can enter freshwater lakes through many sources. They can act as carriers to adsorb bacteria, virus, or pollutants (e.g., heavy metal and toxic organic compounds) that threaten human health through food chain. Microplastics can exist in surface water and sediments in freshwater lakes after they enter the lakes through discharge points. Wastewater discharge is the main cause of lake eutrophication and is the main emission source of microplastics. The correlation between lake trophic state and microplastic abundance has been rarely reported. This study investigated the microplastic contamination in surface water and sediments of 18 lakes along the middle and lower reaches of the Yangtze River Basin in the period of August-September 2018. The correlation between lake trophic state and microplastic abundance in surface water and sediments was investigated and discussed. The microplastic abundance in surface water was approximately two orders of magnitude lower than that in sediments in all 18 lakes. Hong Lake had the highest microplastic abundance in surface water sample, and Nantaizi Lake had the highest microplastic abundance in sediment sample. The dominant microplastic shape was fiber of 93.81% in surface water sample and 94.77% in sediment sample. Blue-colored microplastics were dominant in nearly all lakes in surface water sample (around 40%-60%) and sediment sample (around 60%-80%), followed by purple- and green-colored ones. The microplastics size <1 mm was dominant in surface water sample (around 40%-60%) and sediment sample (around 50%-80%). The dominant material was polypropylene in surface water sample (around 60%-80%) and sediment sample (around 40%-60%).
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Affiliation(s)
- Lu Li
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Shixiong Geng
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; School of Materials Science and Chemical Engineering, Anhui Jianzhu University, Hefei, 230022, China
| | - Chenxi Wu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Kang Song
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
| | - Fuhong Sun
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - C Visvanathan
- School of Environment, Resources and Development, Asian Institute of Technology, Pathum Thani, 12120, Thailand
| | - Fazhi Xie
- School of Materials Science and Chemical Engineering, Anhui Jianzhu University, Hefei, 230022, China
| | - Qilin Wang
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Ultimo, NSW 2007, Australia
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Joshi P, Visvanathan C. Sustainable management practices of food waste in Asia: Technological and policy drivers. J Environ Manage 2019; 247:538-550. [PMID: 31260920 DOI: 10.1016/j.jenvman.2019.06.079] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [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: 01/10/2019] [Revised: 06/09/2019] [Accepted: 06/15/2019] [Indexed: 06/09/2023]
Abstract
The policies and technological drivers to manage food waste in Asia have been shaped by the increasing awareness of the countries to this issue, their commitment to national and international development goals, their socio-economic constraints, and their recognition of the potency to recover nutrients and energy from food waste. The concept of reduce, reuse and recycle (the 3R principles) streamline the existing food waste management policies, and scrutinising the gaps and challenges led to a conclusion that most of the countries emphasise food waste segregation and treatment instead of prevention at source itself. Furthermore, a qualitative SWOT analysis of five prevailing treatment options led to a conclusion that animal feeding, incineration, and landfilling are unsustainable since they pose various health and environmental hazard risks. It was further concluded that anaerobic digestion was the preferred option than aerobic digestion (composting) considering the characteristics of the available food waste in Asia as well as the underlying environmental and economic benefits. Moreover, decentralised, community-scale, anaerobic digestion system has been gaining traction over centralised, large-scale system because of their lower energy footprint, ease of operation, need for lesser resources, lower operation and maintenance costs, and higher chances of public acceptance. It was also observed that the policy to gain energy from segregated food waste is a larger driving force for the efforts to promote anaerobic digestion and thereby manage food waste sustainably.
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Affiliation(s)
- Prabhat Joshi
- Department of Energy, Environment and Climate Change, School of Environment, Resources and Development, Asian Institute of Technology, P.O. Box 4, Khlong Luang, Pathumthani, 12120, Thailand
| | - Chettiyappan Visvanathan
- Department of Energy, Environment and Climate Change, School of Environment, Resources and Development, Asian Institute of Technology, P.O. Box 4, Khlong Luang, Pathumthani, 12120, Thailand.
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Rene ER, Thanh BX, Dan NP, Visvanathan C. Preface to the ISEAC 5 - Asia special issue. J Environ Manage 2019; 234:180. [PMID: 30622015 DOI: 10.1016/j.jenvman.2018.12.099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Affiliation(s)
- Eldon R Rene
- IHE-Delft Institute of Water Education, the Netherlands.
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Logan M, Visvanathan C. Management strategies for anaerobic digestate of organic fraction of municipal solid waste: Current status and future prospects. Waste Manag Res 2019; 37:27-39. [PMID: 30761956 DOI: 10.1177/0734242x18816793] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Anaerobic digestion has emerged as the preferred treatment for organic fraction of municipal solid waste. Digestate management strategies are devised not only for safe disposal but also to increase the value and marketability. Regulations and standards for digestate management are framed to address the pollution concerns, conserve vulnerable zones, prevent communicable diseases, and to educate on digestate storage and applications. Regulations and the desired end uses are the main drivers for the enhancement of digestate through pretreatment, in vessel cleaning, and post-digestion treatment technologies for solid and liquid fractions of digestate. The current management practice involves utilization of digestate for land application either as fertilizer or soil improver. Prospects are bright for alternative usage such as microalgal cultivation, biofuel and bioethanol production. Presently, the focus of optimization of the anaerobic digestion process is directed only towards enhancing biogas yield, ignoring the quality of digestate produced. A paradigm shift is needed in the approach from 'biogas optimization' to 'integrated biogas-digestate optimization'.
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Affiliation(s)
- Mohanakrishnan Logan
- Department of Energy, Environment and Climate Change, School of Environment, Resources and Development, Asian Institute of Technology, Khlong Luang, Pathumthani, Thailand
| | - Chettiyappan Visvanathan
- Department of Energy, Environment and Climate Change, School of Environment, Resources and Development, Asian Institute of Technology, Khlong Luang, Pathumthani, Thailand
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Li L, Visvanathan C. Effect of PVA-gel filling ratio in attached growth membrane bioreactor for treating polluted surface water. Environ Technol 2019; 40:219-225. [PMID: 28967335 DOI: 10.1080/09593330.2017.1384854] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [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: 04/13/2017] [Accepted: 08/04/2017] [Indexed: 06/07/2023]
Abstract
Surface water has been facing increasing loads of various types of organic contamination due to human activities. Attached growth membrane bioreactor (aMBR) has been reported as a promising approach in treating polluted surface water. By using bio-carrier to provide biodegradation and utilize organic pollutants as substrates, aMBR was able to integrate biodegradation and physical rejection in one system. The filling ratio of polyvinyl alcohol gel (PVA-gel), which is an important bioprocess contributor in an aMBR system, was analyzed by batch test and lab-scale aMBR in this study. Batch test with various filling ratios (2%, 5%, 10%, 15% and 30%) were carried out. Oxygen uptake rate (OUR) and specific oxygen uptake rate were used for the comparison of bioactivities. Five percent filling ratio had the highest OUR results of 3.6 mg/L h obtained from the batch test. The chosen filling ratios were tested in a lab-scale aMBR system with hydraulic retention time (HRT) of 1, 2, 2.5 and 3 h. Results shown that at HRT 2.5 h, the aMBR system had the lowest membrane fouling. PVA-gel was able to reject more organic matters than a naturally immobilized membrane bioreactor system, and thus mitigated membrane fouling in the aMBR system.
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Affiliation(s)
- Lu Li
- a School of Environment, Resources and Development , Asian Institute of Technology , Pathumthani , Thailand
| | - C Visvanathan
- a School of Environment, Resources and Development , Asian Institute of Technology , Pathumthani , Thailand
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Li L, Song K, Visvanathan C. Performances study of UV/O 3-aMBR recirculation system in treating polluted surface water. Bioresour Technol 2018; 267:797-801. [PMID: 30017366 DOI: 10.1016/j.biortech.2018.07.041] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [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: 05/12/2018] [Revised: 07/05/2018] [Accepted: 07/08/2018] [Indexed: 06/08/2023]
Abstract
This study used UV/O3-aMBR system for treating polluted surface water with CODMn around 10 mg/L, to improve the removal of non-biodegradable components. UV/O3 was used in the recirculation stream, partially treating the recalcitrant in aMBR permeate to improve its biodegradability, and then send back to aMBR for biodegradation. Removal performance of UV/O3-aMBR system with recirculation ratio 20, 40, 60 and 80% was tested and compared. The removal of CODMn, UV254 and NH3-N increased with the increment of recirculation ratio. UV/O3-aMBR system has higher recalcitrant removal performance and less membrane fouling. The fluorescent dissolved organic matter (FDOM) was largely reduced in UV/O3-aMBR system, and the system hydrophilicity was higher than aMBR system. The Modified Stover Kincanoon model was able to describe UV/O3-aMBR system; and has higher Umax than aMBR system. UV/O3-aMBR can be develop as an effective technology in improving recalcitrant removal in polluted surface water treatment.
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Affiliation(s)
- Lu Li
- Center for Water Environmental Engineering, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
| | - Kang Song
- Center for Water Environmental Engineering, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - C Visvanathan
- School of Environment, Resources and Development, Asian Institute of Technology, Pathumthani 12120, Thailand
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Rajput AA, Visvanathan C. Effect of thermal pretreatment on chemical composition, physical structure and biogas production kinetics of wheat straw. J Environ Manage 2018; 221:45-52. [PMID: 29793209 DOI: 10.1016/j.jenvman.2018.05.011] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [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: 12/12/2017] [Revised: 04/29/2018] [Accepted: 05/05/2018] [Indexed: 05/19/2023]
Abstract
Hard lignocellulosic structure of wheat straw is the main hindrance in its anaerobic digestion. Thus, a laboratory scale batch experiment was conducted to study the effect of thermal pretreatment on anaerobic digestion of wheat straw. For this purpose, different thermal pretreatment temperatures of 120, 140, 160 and 180 °C were studied and the results were compared with raw wheat straw. Significant differences in biogas production were observed at temperature higher than 160 °C. Highest biogas yield of 615 Nml/gVS and volatile solids reduction of 69% was observed from wheat straw pretreated at 180 °C. Wheat straw pretreated at 180 °C showed 53% higher biogas yield as compared to untreated. Further, FTIR analysis revealed change in chemical bonds of lignocellulosic structure of wheat straw. Modified Gompertz model was best fitted on biogas production data and predicted shorter lag phase time and higher biogas production as the pretreatment temperature increased. Overall, change in lignocellulosic structure and increase in cellulose content were the main reason in enhancing biogas production.
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Affiliation(s)
- Asad Ayub Rajput
- Institute of Environmental Sciences and Engineering (IESE), School of Civil and Environmental Engineering (SCEE), National University of Sciences and Technology (NUST), Islamabad 44000, Pakistan
| | - Chettiyappan Visvanathan
- Environmental Engineering and Management, School of Environment, Resources and Development, Asian Institute of Technology, Bangkok, Thailand
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Li L, Suwanate S, Visvanathan C. Performance evaluation of attached growth membrane bioreactor for treating polluted surface water. Bioresour Technol 2017; 240:3-8. [PMID: 28162925 DOI: 10.1016/j.biortech.2017.01.043] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [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: 12/03/2016] [Revised: 01/21/2017] [Accepted: 01/24/2017] [Indexed: 06/06/2023]
Abstract
Attached growth membrane bioreactor (aMBR) process was investigated for treating polluted surface water with CODMn around 10mg/L of raw water. Lab scale reactors, aMBR with 15% PVA-gel as carrier and conventional membrane filtration reactor (MF) were tested in parallel. aMBR achieved two times higher CODMn removal than MF system. Ammonia removal occurred almost completely in both MF and aMBR system - around 94% and 96%, respectively. Permeate turbidity was almost totally removed while UV254 removal was around 15% in MF and 20% in aMBR system. aMBR system largely mitigated membrane fouling and prolonged the system operation time. Results showed 2h hydraulic retention time provided relatively higher removal efficiency and stable operation performance. Modified Stover Kincannon model was able to match the aMBR system.
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Affiliation(s)
- Lu Li
- School of Environment, Resources and Development, Asian Institute of Technology, Pathumthani 12120, Thailand
| | - Siwaporn Suwanate
- School of Environment, Resources and Development, Asian Institute of Technology, Pathumthani 12120, Thailand
| | - C Visvanathan
- School of Environment, Resources and Development, Asian Institute of Technology, Pathumthani 12120, Thailand.
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Asami T, Katayama H, Torrey JR, Visvanathan C, Furumai H. Evaluation of virus removal efficiency of coagulation-sedimentation and rapid sand filtration processes in a drinking water treatment plant in Bangkok, Thailand. Water Res 2016; 101:84-94. [PMID: 27258619 DOI: 10.1016/j.watres.2016.05.012] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [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: 11/23/2015] [Revised: 04/12/2016] [Accepted: 05/03/2016] [Indexed: 05/03/2023]
Abstract
In order to properly assess and manage the risk of infection by enteric viruses in tap water, virus removal efficiency should be evaluated quantitatively for individual processes in actual drinking water treatment plants (DWTPs); however, there have been only a few studies due to technical difficulties in quantifying low virus concentration in water samples. In this study, the removal efficiency of indigenous viruses was evaluated for coagulation-sedimentation (CS) and rapid sand filtration (RSF) processes in a DWTP in Bangkok, Thailand by measuring the concentration of viruses before and after treatment processes using real-time polymerase chain reaction (qPCR). Water samples were collected and concentrated from raw source water, after CS, and after RSF, and inhibitory substances in water samples were reduced by use of a hydrophobic resin (DAX-8). Pepper mild mottle virus (PMMoV) and JC polyomavirus (JC PyV) were found to be highly prevalent in raw waters, with concentrations of 10(2.88 ± 0.35) and 10(3.06 ± 0.42) copies/L (geometric mean ± S.D.), respectively. Step-wise removal efficiencies were calculated for individual processes, with some variation observed between wet and dry seasons. During the wet season, PMMoV was removed less by CS and more by RSF on average (0.40 log10 vs 1.26 log10, respectively), while the reverse was true for JC PyV (1.91 log10 vs 0.49 log10, respectively). Both viruses were removed similarly during the dry season, with CS removing the most virus (PMMoV, 1.61 log10 and 0.78 log10; JC PyV, 1.70 log10, and 0.59 log10; CS and RSF, respectively). These differences between seasons were potentially due to variations in raw water quality and the characteristics of the viruses themselves. These results suggest that PMMoV and JC PyV, which are more prevalent in environmental waters than the other enteric viruses evaluated in this study, could be useful in determining viral fate for the risk management of viruses in water treatment processes in actual full-scale DWTPs.
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Affiliation(s)
- Tatsuya Asami
- Department of Urban Engineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan
| | - Hiroyuki Katayama
- Department of Urban Engineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan.
| | - Jason Robert Torrey
- Department of Urban Engineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan
| | - Chettiyappan Visvanathan
- Environmental Engineering and Management Program, School of Environment, Resources and Development, Asian Institute of Technology, P.O. Box 4, Klong Luang, Pathumthani 12120, Thailand
| | - Hiroaki Furumai
- Research Center for Water Environment Technology, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan
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Haider MR, Yousaf S, Malik RN, Visvanathan C. Effect of mixing ratio of food waste and rice husk co-digestion and substrate to inoculum ratio on biogas production. Bioresour Technol 2015; 190:451-7. [PMID: 25818922 DOI: 10.1016/j.biortech.2015.02.105] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [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: 01/07/2015] [Revised: 02/25/2015] [Accepted: 02/26/2015] [Indexed: 05/25/2023]
Abstract
Aim of this study was to find out suitable mixing ratio of food waste and rice husk for their co-digestion in order to overcome VFA accumulation in digestion of food waste alone. Four mixing ratios of food waste and rice husk with C/N ratios of 20, 25, 30 and 35 were subjected to a lab scale anaerobic batch experiment under mesophilic conditions. Highest specific biogas yield of 584L/kgVS was obtained from feedstock with C/N ratio of 20. Biogas yield decreased with decrease in food waste proportion. Further, fresh cow dung was used as inoculum to investigate optimum S/I ratio with the selected feedstock. In experiment 2, feedstock with C/N ratio 20 was subjected to anaerobic digestion at five S/I ratios of 0.25, 0.5, 1.0, 1.5 and 2.0. Specific biogas yield of 557L/kgVS was obtained at S/I ratio of 0.25. However, VFA accumulation occurred at higher S/I ratios due to higher organic loadings.
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Affiliation(s)
- Muhammad Rizwan Haider
- Department of Environmental Sciences, Quaid-i-Azam University, Islamabad 45320, Pakistan.
| | - Sohail Yousaf
- Department of Environmental Sciences, Quaid-i-Azam University, Islamabad 45320, Pakistan.
| | - Riffat Naseem Malik
- Department of Environmental Sciences, Quaid-i-Azam University, Islamabad 45320, Pakistan.
| | - Chettiyappan Visvanathan
- Environmental Engineering and Management, School of Environment, Resources and Development, Asian Institute of Technology, Bangkok, Thailand.
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Sensai P, Thangamani A, Visvanathan C. Thermophilic co-digestion feasibility of distillers grains and swine manure: effect of C/N ratio and organic loading rate during high solid anaerobic digestion (HSAD). Environ Technol 2014; 35:2569-2574. [PMID: 25145212 DOI: 10.1080/09593330.2014.913688] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Anaerobic co-digestion of high solids containing distillers grains and swine manure (total solids, 27 +/- 2% and 18 +/- 2%, respectively) was evaluated in this study to assess the effect of C/N ratio and organic loading rate (OLR). Feed mixture was balanced to achieve a C/N ratio of 30/1 by mixing distillers grains and swine manure. Pilot-scale co-digestion of distillers grains and swine manure was carried out under thermophilic conditions in the continuous mode for seven different OLRs from R1 to R7 (3.5, 5, 6, 8, 10, 12 and 14 kg VS/m3 day) under high solid anaerobic digestion. The methane yield and volatile solid (VS) removal were consistent; ranging from 0.33 to 0.34 m3CH4/kg VS day and 50-53%, respectively, until OLR 8 kg VS/m3 day. After which methane yield and VS removal significantly decreased to 0.26 m3 CH4/kg VS day and 42%, respectively, when OLR was increased to 14 kg VS/m3 day. However, during operation, at OLR of 10 kg VS/m3 day, the methane yield and VS removal increased after the 19th day to 0.33 m3 CH4/kg VS day and 46%, respectively, indicating that a longer acclimatization period is required by methanogens at a higher loading rate.
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Chaikasem S, Abeynayaka A, Visvanathan C. Effect of polyvinyl alcohol hydrogel as a biocarrier on volatile fatty acids production of a two-stage thermophilic anaerobic membrane bioreactor. Bioresour Technol 2014; 168:100-105. [PMID: 24803272 DOI: 10.1016/j.biortech.2014.04.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [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: 01/05/2014] [Revised: 04/05/2014] [Accepted: 04/07/2014] [Indexed: 06/03/2023]
Abstract
This work studied the effect of polyvinyl alcohol hydrogel (PVA-gel) beads, as an effective biocarrier for volatile fatty acid (VFA) production in hydrolytic reactor of a two-stage thermophilic anaerobic membrane bioreactor (TAnMBR). The two-stage TAnMBR, treating synthetic high strength particulate wastewater with influent chemical oxygen demand (COD) [16.4±0.8 g/L], was operated at 55 °C. Under steady state conditions, the reactor was operated at an organic loading rate of 8.2±0.4 kg COD/m(3) d. Operational performance of the system was monitored by assessing VFA composition and quantity, methane production and COD removal efficiency. Increment of VFA production was observed with PVA-gel addition. Hydrolytic effluent contained large amount of acetic acid and n-butyric acid. However, increase in VFA production adversely affected the methanogenic reactor performance due to lack of methanogenic archaea.
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Affiliation(s)
- Supawat Chaikasem
- Environmental Engineering and Management Program, School of Environment Resources and Development, Asian Institute of Technology, P.O. Box 4, Klong Luang, Pathumthani 12120, Thailand
| | - Amila Abeynayaka
- Department of Urban Engineering, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Chettiyappan Visvanathan
- Environmental Engineering and Management Program, School of Environment Resources and Development, Asian Institute of Technology, P.O. Box 4, Klong Luang, Pathumthani 12120, Thailand.
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Jacob P, Kashyap P, Suparat T, Visvanathan C. Dealing with emerging waste streams: used tyre assessment in Thailand using material flow analysis. Waste Manag Res 2014; 32:918-926. [PMID: 25106533 DOI: 10.1177/0734242x14543554] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Increasing urbanisation and automobile use have given rise to an increase in global tyre waste generation. A tyre becomes waste once it wears out and is no longer fit for its original purpose, and is thus in its end-of-life state. Unlike in developed countries, where waste tyre management has already become a significant issue, it is rarely a priority waste stream in developing countries. Hence, a large quantity of waste tyres ends up either in the open environment or in landfill. In Thailand, waste tyre management is in its infancy, with increased tyre production and wider use of vehicles, but low levels of recycling, leaving scope for more appropriate policies, plans and strategies to increase waste tyre recycling. This article describes the journey of waste tyres in Thailand in terms of recycling and recovery, and disposal. Material flow analysis was used as a tool to quantify the flows and accumulation of waste tyres in Thailand in 2012. The study revealed that, in Thailand in 2012, waste tyre management was still biased towards destructive technologies (48.9%), rather than material recovery involving rubber reclamation, retreading tyres and whole and shredded tyre applications (6.7%). Despite having both economic and environmental benefits, 44.4% of used tyres in 2012 were dumped in the open environment, and the remaining 0.05% in landfills.
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Affiliation(s)
- Paul Jacob
- Environmental Engineering and Management Program, Asian Institute of Technology, Pathumthani, Thailand
| | - Prakriti Kashyap
- Environmental Engineering and Management Program, Asian Institute of Technology, Pathumthani, Thailand
| | - Tasawan Suparat
- Environmental Engineering and Management Program, Asian Institute of Technology, Pathumthani, Thailand
| | - Chettiyappan Visvanathan
- Environmental Engineering and Management Program, Asian Institute of Technology, Pathumthani, Thailand
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Caniato M, Vaccari M, Visvanathan C, Zurbrügg C. Using social network and stakeholder analysis to help evaluate infectious waste management: a step towards a holistic assessment. Waste Manag 2014; 34:938-951. [PMID: 24636007 DOI: 10.1016/j.wasman.2014.02.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [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: 10/09/2013] [Revised: 02/07/2014] [Accepted: 02/12/2014] [Indexed: 06/03/2023]
Abstract
Assessing the strengths and weaknesses of a solid waste management scheme requires an accurate analysis and integration of several determining features. In addition to the technical aspects, any such system shows a complex interaction of actors with varying stakes, decision-making power and influence, as well as a favourable or disabling environment. When capitalizing on the knowledge and experience from a specific case, it is also crucial that experts do not "forget" or underestimate the importance of such social determinants and that they are familiar with the methods and tools to assess them. Social network analysis (SNA) and stakeholder analysis (SA) methods can be successfully applied to better understand actors' role and actions, analyse driving forces and existing coordination among stakeholders, as well as identify bottlenecks in communication which affect daily operations or strategic planning for the future way forward. SNA and SA, appropriately adjusted for a certain system, can provide a useful integration to methods by assessing other aspects to ensure a comprehensive picture of the situation. This paper describes how to integrate SNA and SA in order to survey a solid waste management system. This paper presents the results of an analysis of On-Nuch infectious waste incinerator in Bangkok, Thailand. Stakeholders were interviewed and asked to prioritize characteristics and relationships which they consider particularly important for system development and success of the scheme. In such a way, a large quantity of information about organization, communication between stakeholders and their perception about operation, environmental and health impact, and potential alternatives for the system was collected in a systematic way. The survey results suggest that stakeholders are generally satisfied with the system operation, though communication should be improved. Moreover, stakeholders should be strategically more involved in system development planning, according to their characteristics, to prevent negative reactions.
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Affiliation(s)
- Marco Caniato
- University of Brescia, Research Centre on Appropriate Technologies for Environmental Management in Developing Countries (CeTAmb), Via Branze, 43, 25123 Brescia, Italy.
| | - Mentore Vaccari
- University of Brescia, Research Centre on Appropriate Technologies for Environmental Management in Developing Countries (CeTAmb), Via Branze, 43, 25123 Brescia, Italy.
| | - Chettiyappan Visvanathan
- Asian Institute of Technology (AIT), School of Environment, Resources and Development (SERD), P.O. Box 4, Klong Luang, Pathumthani 12120, Thailand.
| | - Christian Zurbrügg
- University of Brescia, Research Centre on Appropriate Technologies for Environmental Management in Developing Countries (CeTAmb), Via Branze, 43, 25123 Brescia, Italy; Eawag: Swiss Federal Institute of Aquatic Science and Technology, Department of Water and Sanitation in Developing Countries (Sandec), Ueberlandstrasse 133, 8600 Duebendorf, Switzerland.
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Thanh BX, Dan NP, Visvanathan C. Low flux submerged membrane bioreactor treating high strength leachate from a solid waste transfer station. Bioresour Technol 2013; 141:25-28. [PMID: 23562178 DOI: 10.1016/j.biortech.2013.02.066] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Revised: 02/18/2013] [Accepted: 02/20/2013] [Indexed: 06/02/2023]
Abstract
A submerged membrane bioreactor was employed to treat high strength leachate generating from a solid waste transfer station. The reactor was operated at low fluxes of 1.2; 2.4; 3.8 and 5.1 LMH. The organic loading rate (OLR) ranged from 2 to 10 kg COD/m(3)day. Results show that 97% removal efficiency of COD at flux of 2.4 LMH. The highest removal of ammonia nitrogen and total nitrogen was 92.0 ± 1.5% and 88.0 ± 2.0% respectively at flux of 3.8 LMH. Fouling rates were observed to be 0.075; 0.121; 3.186 and 6.374 kPa/day for the fluxes of 1.2; 2.4; 3.8 and 5.1 LMH, respectively. Membrane fouled very slowly at low flux operation. The sustainable flux was identified to be less than 2.4 LMH for treating high strength leachate. It reveals less fouling was able to achieve for high strength wastewater by reducing the membrane flux.
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Affiliation(s)
- Bui Xuan Thanh
- Faculty of Environment, Ho Chi Minh City University of Technology, 268 Ly Thuong Kiet Str., District 10, Ho Chi Minh City, Viet Nam.
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Körner I, Visvanathan C. Perspectives of composting and anaerobic digestion technologies for the treatment of organic fraction of municipal solid waste in Europe and Asia. ACTA ACUST UNITED AC 2013. [DOI: 10.1504/ijewm.2013.051844] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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34
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Wong JWC, Tyagi RD, Visvanathan C, Yan JH, Selvam A. Special issue on 'Advanced treatment technologies for waste recycling': selected papers from the 'International Conference on Solid Waste-Moving Towards Sustainable Resource Management', 2-6 May 2011, Hong Kong Sar. Environ Technol 2012; 33:2479. [PMID: 23437643 DOI: 10.1080/09593330.2012.742621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
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Jamal Khan S, Visvanathan C, Jegatheesan V. Influence of biofilm carriers on membrane fouling propensity in moving biofilm membrane bioreactor. Bioresour Technol 2012; 113:161-164. [PMID: 22342044 DOI: 10.1016/j.biortech.2012.01.033] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2011] [Revised: 01/09/2012] [Accepted: 01/10/2012] [Indexed: 05/31/2023]
Abstract
In moving biofilm membrane bioreactor (MB-MBR) sponge carriers for biofilm growth were coupled with conventional submerged membrane bioreactor (C-MBR). This study compared the fouling propensity of C-MBR with MB-MBR and investigated factors affecting fouling variations in both the systems. Membrane fouling tendencies were monitored in terms of trans-membrane pressure (TMP) and the fouling characterization included membrane fouling resistances in situ and specific cake resistance (SCR) in batch filtration cell. Comparison of TMP profiles depicted prolong filtration periods in MB-MBR. Cake layer resistance (R(c)), pore blocking resistance (R(p)) as well as SCR were higher in C-MBR. The study reveals that hybrid biomass in MB-MBR creates relatively more porous cake structure in the absence of filamentous bacteria which were found in abundance in C-MBR. Filamentous bacteria were also responsible for the release of high concentration of carbohydrates in the form of soluble extra polymeric substance (EPS) contributing to higher R(p) in C-MBR.
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Affiliation(s)
- S Jamal Khan
- Institute of Environmental Sciences and Engineering, School of Civil and Environmental Engineering, National University of Sciences and Technology (NUST), Islamabad, Pakistan.
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36
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Jamal Khan S, Visvanathan C, Jegatheesan V. Effect of powdered activated carbon (PAC) and cationic polymer on biofouling mitigation in hybrid MBRs. Bioresour Technol 2012; 113:165-168. [PMID: 22264429 DOI: 10.1016/j.biortech.2011.12.107] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2011] [Revised: 12/19/2011] [Accepted: 12/20/2011] [Indexed: 05/31/2023]
Abstract
In this study, the influence of powdered activated carbon (PAC) and cationic polymer (MPE50) was investigated on the fouling propensity in hybrid MBRs. Three laboratory scale MBRs were operated simultaneously including MBR(Control), MBR(PAC), and MBR(Polymer). Optimum dosages of PAC and polymer to the MBR(PAC) and MBR(Polymer), respectively were determined using jar tests. It was found that the MBR(PAC) exhibited low fouling tendency and prolonged filtration as compared to the other MBRs. Improved filtration in MBR(PAC) was attributed to the flocculation and adsorption phenomena. The effective stability of the biomass by PAC in the form of biological activated carbon (BAC) was verified by the increase in mean particle size. The BAC aided sludge layer exhibited porous cake structure resulting in the prolong filtration. However, both the membrane hybrid systems revealed effective adsorption of organic matter by 40% reduction in the soluble EPS concentration.
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Affiliation(s)
- S Jamal Khan
- Institute of Environmental Sciences and Engineering, School of Civil and Environmental Engineering, National University of Sciences and Technology (NUST), Islamabad, Pakistan.
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Karthikeyan OP, Visvanathan C. Effect of C/N ratio and ammonia-N accumulation in a pilot-scale thermophilic dry anaerobic digester. Bioresour Technol 2012; 113:294-302. [PMID: 22386200 DOI: 10.1016/j.biortech.2012.02.028] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2011] [Revised: 02/01/2012] [Accepted: 02/03/2012] [Indexed: 05/31/2023]
Abstract
The effect of ammonia-N accumulation in a dry anaerobic digestion was studied effectively using pilot-scale thermophilic reactor. Two simulations were prepared to attain C/N ratio 27 and C/N ratio 32 using bio-degradable feedstocks such as food waste, fruit and vegetable waste, green waste and paper waste. Organic loading rates and digestate recirculation rates were varied during different time intervals and the performance was evaluated using parameters like pH, VFA, Alkalinity, ammonia-N and biogas yield. Results showed that the simulation with C/N ratio 32 had about 30% less ammonia in digestate as compared to that with C/N ratio 27. The system performed well up to organic loading rate (OLR) 7-10 kgVS/m(3)d and retention time up to 19 days, with surplus energy production of 50-73%. Moreover, a free ammonia accumulation/inhibition effect was documented and methods to overcome the adverse effects were discussed.
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Wijekoon KC, Visvanathan C, Abeynayaka A. Effect of organic loading rate on VFA production, organic matter removal and microbial activity of a two-stage thermophilic anaerobic membrane bioreactor. Bioresour Technol 2011; 102:5353-5360. [PMID: 21256737 DOI: 10.1016/j.biortech.2010.12.081] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2010] [Revised: 12/20/2010] [Accepted: 12/20/2010] [Indexed: 05/30/2023]
Abstract
This study focused on the VFA (volatile fatty acid) profile variation with organic loading rate (OLR) of a two stage thermophilic anaerobic membrane bioreactor (TAnMBR). The two stage TAnMBR treating high strength molasses-based synthetic wastewater was operated under a side-stream partial sedimentation mode at 55°C. Reactor performances were studied at different OLR ranging from 5 to 12 kg COD m(-3) d(-1). Operational performance of TAnMBR was monitored by assessing biological activity, organic removal efficiency, and VFA. The major intermediate products of anaerobic digestion were identified as acetate, propionate, iso-butyrate, n-butyrate and valerate. Among them acetate and n-butyrate were identified as the most abundant components. Increase of OLR changes the predominant VFA type from acetic acid to n-butyric acid and the total VFA concentration was increased with increased OLR. Moreover, increased OLR increased organic removal efficiency up to second loading rate and dropped in third loading rate while biological activity was increased continuously.
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Affiliation(s)
- Kaushalya C Wijekoon
- Environmental Engineering and Management Program, School of Environment, Resources and Development, Asian Institute of Technology, P.O. Box 4, Klong Luang, Pathumthani 12120, Thailand
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Abeynayaka A, Visvanathan C. Performance comparison of mesophilic and thermophilic aerobic sidestream membrane bioreactors treating high strength wastewater. Bioresour Technol 2011; 102:5345-5352. [PMID: 21145734 DOI: 10.1016/j.biortech.2010.11.079] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2010] [Revised: 11/17/2010] [Accepted: 11/18/2010] [Indexed: 05/30/2023]
Abstract
This study compares membrane fouling and removal efficiencies of organic and nitrogen in thermophilic (47 and 60°C) and mesophilic (30°C) aerobic sidestream airlift membrane bioreactors (SA-MBRs). These reactors were fed with high strength molasses-based synthetic wastewater at an organic loading rate (OLR) of 24.75 kg COD/m(3)d. Removal efficiencies of COD, NH(4)(+) and TKN were compared. The sidestream filtration was conducted with microfilter and ultrafilter. SA-MBRs with microfilter were operated in continuous and intermittent operation modes, while with the ultrafilter only continuous operation mode was employed. The excessive membrane fouling observed in thermophilic SA-MBRs with microfilter under continuous filtration mode, could be significantly reduced by the application of cake layer pre-coating or replacing microfilter with ultrafilter. This membrane fouling under the thermophilic condition could be linked to higher protein generation within the reactors. Soluble COD removal efficiencies were higher in thermophilic conditions while the sludge yields were significantly low in thermophilic SA-MBRs.
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Affiliation(s)
- Amila Abeynayaka
- Environmental Engineering and Management Program, School of Environment, Resource and Development, Asian Institute of Technology, P.O. Box 4, Klong Luang, Pathumthani 12120, Thailand
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Jamal Khan S, Ilyas S, Javid S, Visvanathan C, Jegatheesan V. Performance of suspended and attached growth MBR systems in treating high strength synthetic wastewater. Bioresour Technol 2011; 102:5331-5336. [PMID: 20974529 DOI: 10.1016/j.biortech.2010.09.100] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Revised: 09/22/2010] [Accepted: 09/24/2010] [Indexed: 05/30/2023]
Abstract
The performance of laboratory-scale attached growth (AG) and suspended growth (SG) membrane bioreactors (MBRs) was evaluated in treating synthetic wastewater simulating high strength domestic wastewater. This study investigated the influence of sponge suspended carriers in AG-MBR system, occupying 15% reactor volume, on the removal of chemical oxygen demand (COD), total nitrogen (TN) and total phosphorus (TP), and compared it to that of SG-MBR. Results showed that the removal efficiencies of COD, TN and TP in AG-MBR were 98%, 89% and 58%, respectively as compared to 98%, 74% and 38%, respectively in SG-MBR. Improved TN removal in AG-MBR systems was primarily based on simultaneous nitrification and denitrification (SND) process. These results infer that the presence of small bio-particles having higher microbial activity and the growth of complex biomass captured within the suspended sponge carriers resulted in improved TN and TP removal in AG-MBR.
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Affiliation(s)
- S Jamal Khan
- Institute of Environmental Science and Engineering, School of Civil and Environmental Engineering, National University of Sciences and Technology (NUST), Islamabad, Pakistan.
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41
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Visvanathan C, Karthikeyan OP, Park KH. Sustainable landfilling in tropical conditions: comparison between open and closed cell approach. Waste Manag Res 2011; 29:386-396. [PMID: 20855353 DOI: 10.1177/0734242x10383078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Two landfill test cells were constructed in a tropical climate using locally available low-cost materials. One cell was operated without a cover on the municipal solid waste to simulate 'open landfill' conditions and the other cell was covered to create 'closed landfill' conditions. Both test cells were monitored over a period of 290 days under rainy, dry and artificial wetting conditions. Due to the relatively high compaction density of waste in the closed test cell, the substrate settlement was gradual and comparatively lower than in the open test cell. Multiple top covers in the closed test cell resulted in significant run-off of incident precipitation during the rainy season, which delayed the waste stabilization and subsequently produced a lesser volume of leachate. On the other hand, operation of the open test cell was found to be advantageous in terms of leachate management and substrate settlement along with waste stabilization pattern. Infiltration of rain-water into the waste mass leached out the maximum organic pollutants and oxidized the nitrogen content, which is deemed to be a benefit of operating an open cell landfill under tropical conditions. Artificial wetting during dry periods by recirculation of stored leachate notably accelerated the waste stabilization and secondary substrate settlement in the open test cell. The continuous monitoring of ground-water quality from the site showed only seasonal variations.
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Affiliation(s)
- C Visvanathan
- School of Environment, Resources and Development, Asian Institute of Technology, Bangkok, Thailand.
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Abeynayaka A, Visvanathan C. Mesophilic and thermophilic aerobic batch biodegradation, utilization of carbon and nitrogen sources in high-strength wastewater. Bioresour Technol 2011; 102:2358-2366. [PMID: 21075626 DOI: 10.1016/j.biortech.2010.10.096] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2010] [Revised: 10/19/2010] [Accepted: 10/20/2010] [Indexed: 05/30/2023]
Abstract
This study compares organic and nitrogen removals of thermophilic and mesophilic aerobic processes. The experiments were performed in three 7.2L sequential batch reactors (SBRs) operated at 30, 47 and 60°C. Molasses based synthetic wastewater consisting chemical oxygen demand (COD): 11,200 mg/L, total kheljal nitrogen (TKN): 770 mg/L, ammonical nitrogen (NH(4)): 560 mg/L was the feed medium. Biokinetic parameters, COD, NH(4)(+) and TKN removal efficiencies were compared under six different operating conditions. Five times lower sludge production and similar COD removal were observed in thermophilic SBRs compared to mesophilic SBR under 8.25 kg COD/m(3)d loading rate. However at 24.75 kg COD/m(3)d there were no differences in terms of sludge production while COD removals were varied as 59%, 80% and 82% at 30, 47 and 60°C respectively. A mechanism was developed to understand the varying behaviors of thermophilic aerobic process. Stripping is the major mechanism for nitrogen removal in thermophilic SBRs.
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Affiliation(s)
- Amila Abeynayaka
- School of Environment, Resource and Development, Asian Institute of Technology, Klong Luang, Pathumthani, Thailand
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Visvanathan C, Yin NH, Karthikeyan OP. Co-disposal of electronic waste with municipal solid waste in bioreactor landfills. Waste Manag 2010; 30:2608-2614. [PMID: 20829017 DOI: 10.1016/j.wasman.2010.08.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2010] [Revised: 08/01/2010] [Accepted: 08/02/2010] [Indexed: 05/29/2023]
Abstract
Three pilot scale lysimeters were adopted to evaluate the stability pattern and leaching potential of heavy metals from MSW landfills under the E-waste co-disposed condition. One lysimeter served as control and solely filled with MSW, whereas the other two lysimeters were provided with 10% and 25% of E-waste scraps (% by weight), respectively. The reactors were monitored over a period of 280 days at ambient settings with continuous leachate recirculation. Stabilization pattern of carbon appears to be more than 50% in all the three lysimeters with irrespective of their operating conditions. Iron and zinc concentrations were high in leachate during bioreactor landfill operation and correlating with the TCLP leachability test results. In contrast, Pb concentration was around <0.6 mg/L, but which showed maximum leaching potential under TCLP test conditions. But, no heavy metal accumulation was found with leachate recirculation practices in lysimeters. Mobility of the metal content from the E-waste was found to be amplified with the long term disposal or stabilization within landfills. The results showed that the TCLP test cannot be completely reliable tool for measuring long-term leachability of toxic substances under landfill condition; rather landfill lysimeter studies are necessary to get the real scenario.
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Affiliation(s)
- C Visvanathan
- School of Environment, Resources and Development, Asian Institute of Technology, Pathumthani, 12120 Bangkok, Thailand.
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Chiemchaisri C, Charnnok B, Visvanathan C. Recovery of plastic wastes from dumpsite as refuse-derived fuel and its utilization in small gasification system. Bioresour Technol 2010; 101:1522-1527. [PMID: 19758801 DOI: 10.1016/j.biortech.2009.08.061] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2009] [Revised: 08/14/2009] [Accepted: 08/18/2009] [Indexed: 05/28/2023]
Abstract
An effort to utilize solid wastes at dumpsite as refuse-derived fuel (RDF) was carried out. The produced RDF briquette was then utilized in the gasification system. These wastes were initially examined for their physical composition and chemical characteristics. The wastes contained high plastic content of 24.6-44.8%, majority in polyethylene plastic bag form. The plastic wastes were purified by separating them from other components through manual separation and trommel screen after which their content increased to 82.9-89.7%. Subsequently, they were mixed with binding agent (cassava root) and transformed into RDF briquette. Maximum plastic content in RDF briquette was limit to 55% to maintain physical strength and maximum chlorine content. The RDF briquette was tested in a down-draft gasifier. The produced gas contained average energy content of 1.76 MJ/m(3), yielding cold gas efficiency of 66%. The energy production cost from this RDF process was estimated as USD0.05 perkWh.
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Affiliation(s)
- Chart Chiemchaisri
- Department of Environmental Engineering/National Center of Excellence for Environmental and Hazardous Waste Management, Faculty of Engineering, Kasetsart University, Bangkok 10900, Thailand.
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Seng B, Khanal SK, Visvanathan C. Anaerobic digestion of waste activated sludge pretreated by a combined ultrasound and chemical process. Environ Technol 2010; 31:257-265. [PMID: 20426267 DOI: 10.1080/09593330903453236] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Waste activated sludge (WAS) requires a long digestion time because of a rate-limiting hydrolysis step - the first phase of anaerobic digestion. Pretreatment of WAS facilitates the hydrolysis step and improves the digestibility. This study examined the effects of ultrasonic, chemical, and combined chemical-ultrasonic pretreatments on WAS disintegration and its subsequent digestion at different solids retention times (SRTs). The efficient conditions for each pretreatment were evaluated based on per cent soluble chemical oxygen demand (%SCOD). The results showed that the combined chemical-ultrasonic pretreatment resulted in better WAS disintegration, based on %SCOD release, compared with individual chemical and ultrasonic pretreatments. At the optimum operating conditions of the combined chemical-ultrasonic pretreatment (NaOH dose of 10 mg g(-1) TS (total solids) and specific energy input of 3.8 kJ g(-1)TS), the %SCOD release was 18.1% +/- 0.5%, whereas 13.5% +/- 0.9%, 13.0% +/- 0.5% and 1.1% +/- 0.1% corresponded to individual chemical (50 mg g(-1) TS) and ultrasonic (3.8 kJ g(-1) TS) pretreatments and control (without pretreatment), respectively. The anaerobic digestion studies in continuous stirred tank reactors showed an increase in methane production of 23.4% +/- 1.3% and 31.1 +/- 1.2% for digesters fed with WAS pretreated with ultrasonic and combined chemical-ultrasonic, respectively, with respect to controls at the effective SRT of 15 days. The highest total solids removal was achieved in the digester fed with ultrasonic pretreated WAS (16.6% +/- 0.3%), whereas the highest volatile solids removal was achieved from the digester fed with combined chemical-ultrasonic pretreated WAS (24.8 +/- 0.4%). The findings from this study are a useful contribution to new pretreatment techniques in the field of sludge treatment technology through anaerobic digestion.
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Affiliation(s)
- Bunrith Seng
- Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Kofu, Japan.
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Prem Ananth A, Prashanthini V, Visvanathan C. Healthcare waste management in Asia. Waste Management 2010; 30:154-61. [PMID: 19726174 DOI: 10.1016/j.wasman.2009.07.018] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2009] [Revised: 07/20/2009] [Accepted: 07/20/2009] [Indexed: 05/20/2023]
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Khan SJ, Visvanathan C, Jegatheesan V. Prediction of membrane fouling in MBR systems using empirically estimated specific cake resistance. Bioresour Technol 2009; 100:6133-6136. [PMID: 19596569 DOI: 10.1016/j.biortech.2009.06.037] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2009] [Revised: 06/09/2009] [Accepted: 06/11/2009] [Indexed: 05/28/2023]
Abstract
The focus of this study was to empirically estimate the specific cake resistance (SCR) by the variation in shear intensity (G) in four laboratory-scale MBRs. The control reactor (MBR(0)) was operated with aeration only while other MBRs (MBR(150), MBR(300) and MBR(450)) were operated with aeration and mechanical mixing intensities of 150, 300 and 450 rpm, respectively. It was found that the SCR was strongly correlated (R(2)=0.99) with the fouling rates in the MBRs. Moreover, the contribution of cake resistance (R(c)) to the total hydraulic resistance (R(t)) was predominant compared to the irreversible fouling resistance (R(f)). On this basis, the cake filtration model was selected as a predictive tool for membrane fouling. This model was modified by replacing the SCR with its empirical shear intensity relationship. The modified model can predict the fouling rate for a given shear intensity (G) within 80 and 250 s(-1) in a MBR system.
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Affiliation(s)
- S Jamal Khan
- Institute of Environmental Science and Engineering, School of Civil and Environmental Engineering, National University of Sciences and Technology, Sector H-12, Islamabad, Pakistan.
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Kunacheva C, Juanga JP, Visvanathan C. Electrical and electronic waste inventory and management strategies in Bangkok, Thailand. ACTA ACUST UNITED AC 2009. [DOI: 10.1504/ijewm.2009.024703] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Prechthai T, Parkpian P, Visvanathan C. Assessment of heavy metal contamination and its mobilization from municipal solid waste open dumping site. J Hazard Mater 2008; 156:86-94. [PMID: 18207321 DOI: 10.1016/j.jhazmat.2007.11.119] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2007] [Revised: 11/29/2007] [Accepted: 11/30/2007] [Indexed: 05/25/2023]
Abstract
Influence of heavy metals was investigated by conducting various tests on the samples collected from Nonthaburi dumpsite in Thailand. The heavy metal concentration in the solid waste and its mobility potential based on its binding forms was studied. The sequential extraction method was used to determine the binding forms of metals. From the analysis, Zn was found to be highest concentrated heavy metal compared to Mn, Cu, Cr, Cd, Pb, Ni and Hg in the solid waste. From the sequential extraction, Mn, Zn and Cd mostly found in reducible form, showed its susceptibility to be leached easily. Cu and Cr were found predominantly in oxidizable form and stable under anaerobic condition. Pb and Ni were present in residual form, which is inert. The estimated individual contamination factor (C(f)(i)), showed Zn with highest affinity to leach. The concentration level of all the heavy metals in the leachate except for Cr was noticed to be below the National effluent standards. Though, indicated to be safe for disposal, its effect in any concentration proved toxic to the plant life from the seed germination toxicity test using synthetic chelate ethylene diamine tetraacetic acid (EDTA).
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Affiliation(s)
- Tawach Prechthai
- Environmental Engineering and Management Program, School of Environment, Resources and Development, Asian Institute of Technology, Klong Luang Pathumthani, Thailand
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