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Seyedin M, Hassanpour A, Jalali A, Raisee M. Robust optimization of a novel ultraviolet (UV) photoreactor for water disinfection: A neural network approach. CHEMOSPHERE 2024; 362:142788. [PMID: 38977250 DOI: 10.1016/j.chemosphere.2024.142788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 05/30/2024] [Accepted: 07/04/2024] [Indexed: 07/10/2024]
Abstract
To optimize the ultraviolet (UV) water disinfection process, it is crucial to determine the ideal geometric dimensions of a corresponding model that enhance performance while minimizing the impact of uncertain photoreactor inputs. As water treatment directly affects people's lives, it is crucial to eliminate the risks associated with the non-ideal performance of disinfection photoreactors. Input uncertainties greatly affect photoreactor performance, making it essential to develop a robust optimization algorithm in advance to mitigate these effects and minimize the physical and financial resources required for constructing the photoreactors. In the suggested algorithm, a two-objective genetic algorithm is integrated with a non-intrusive polynomial chaos expansion (PCE) technique. Additionally, the Sobol sampling method is employed to select the necessary samples for understanding the system's behavior. An artificial neural network surrogate model is trained using sufficient data points derived from computational fluid dynamics (CFD) simulations. A novel type of UV photoreactors working based on exterior reflectors is chosen to optimize the process with three uncertain input parameters, including UV lamp power, UV transmittance of water, and diffusive fraction of the reflective surface. In addition, four geometrical design variables are considered to find the optimal configuration of the photoreactor. The standard deviation (SD) and the reciprocal of log reduction value (LRV) are set as the objective functions, calculated using PCE. The optimal design provides a LRV of 3.95 with SD of 0.2. The coefficient of variation (CoV) of the model significantly declines up to 7%, indicating the decreased sensitivity of the photoreactor to the input uncertainties. Additionally, it is discovered that the robust model exhibits minimal sensitivity to changes in reflectivity in various flow rates, and its output variability aligns with the SD obtained through robust optimization.
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Affiliation(s)
- Mahla Seyedin
- School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran
| | - Amirhossein Hassanpour
- School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran
| | - Alireza Jalali
- School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran.
| | - Mehrdad Raisee
- School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran
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2
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Dawas A, Rubin AE, Sand N, Ben Mordechay E, Chefetz B, Mordehay V, Cohen N, Radian A, Ilic N, Hubner U, Zucker I. Negligible adsorption and toxicity of microplastic fibers in disinfected secondary effluents. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 356:124377. [PMID: 38897276 DOI: 10.1016/j.envpol.2024.124377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Revised: 06/07/2024] [Accepted: 06/14/2024] [Indexed: 06/21/2024]
Abstract
Wastewater treatment plants play a crucial role in controlling the transport of pollutants to the environment and often discharge persistent contaminants such as synthetic microplastic fibers (MFs) to the ecosystem. In this study, we examined the fate and toxicity of polyethylene terephthalate (PET) MFs fabricated from commercial cloth in post-disinfection secondary effluents by employing conditions that closely mimic disinfection processes applied in wastewater treatment plants. Challenging conventional assumptions, this study illustrated that oxidative treatment by chlorination and ozonation incurred no significant modification to the surface morphology of the MFs. Additionally, experimental results demonstrated that both pristine and oxidized MFs have minimal adsorption potential towards contaminants of emerging concern in both effluents and alkaline water. The limited adsorption was attributed to the inert nature of MFs and low surface area to volume ratio. Slight adsorption was observed for sotalol, sulfamethoxazole, and thiabendazole in alkaline water, where the governing adsorption interactions were suggested to be hydrogen bonding and electrostatic forces. Acute exposure experiments on human cells revealed no immediate toxicity; however, the chronic and long-term consequences of the exposure should be further investigated. Overall, despite the concern associated with MFs pollution, this work demonstrates the overall indifference of MFs in WWTP (i.e., minor effects of disinfection on MFs surface properties and limited adsorption potential toward a mix of trace organic pollutants), which does not change their acute toxicity toward living forms.
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Affiliation(s)
- Anwar Dawas
- Porter School of Earth and Environmental Studies, Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 69978, Israel; School of Mechanical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978, Israel; Institute of Soil, Water and Environmental Sciences, Gilat Research Center, Agricultural Research Organization (ARO) - Volcani Institute, 85820, Israel
| | - Andrey Ethan Rubin
- Porter School of Earth and Environmental Studies, Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Noa Sand
- Porter School of Earth and Environmental Studies, Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 69978, Israel; School of Mechanical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978, Israel
| | - Evyatar Ben Mordechay
- Department of Soil and Water Sciences, Institute of Environmental Sciences, Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 7610001, Israel
| | - Benny Chefetz
- Department of Soil and Water Sciences, Institute of Environmental Sciences, Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 7610001, Israel
| | - Vered Mordehay
- Department of Soil and Water Sciences, Institute of Environmental Sciences, Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 7610001, Israel
| | - Nirit Cohen
- Faculty of Civil and Environmental Engineering, Technion - Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Adi Radian
- Faculty of Civil and Environmental Engineering, Technion - Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Nebojsa Ilic
- Chair of Urban Water Systems Engineering, Technical University of Munich, Am Coulombwall 3, Garching 85748, Germany
| | - Uwe Hubner
- Chair of Urban Water Systems Engineering, Technical University of Munich, Am Coulombwall 3, Garching 85748, Germany; Xylem Services GmbH, Boschstr. 4-14, Herford 32051, Germany
| | - Ines Zucker
- Porter School of Earth and Environmental Studies, Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 69978, Israel; School of Mechanical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978, Israel.
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3
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Yu Y, Wang Z, Yao B, Zhou Y. Occurrence, bioaccumulation, fate, and risk assessment of emerging pollutants in aquatic environments: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 923:171388. [PMID: 38432380 DOI: 10.1016/j.scitotenv.2024.171388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2023] [Revised: 02/12/2024] [Accepted: 02/28/2024] [Indexed: 03/05/2024]
Abstract
Significant concerns on a global scale have been raised in response to the potential adverse impacts of emerging pollutants (EPs) on aquatic creatures. We have carefully reviewed relevant research over the past 10 years. The study focuses on five typical EPs: pharmaceuticals and personal care products (PPCPs), per- and polyfluoroalkyl substances (PFASs), drinking water disinfection byproducts (DBPs), brominated flame retardants (BFRs), and microplastics (MPs). The presence of EPs in the global aquatic environment is source-dependent, with wastewater treatment plants being the main source of EPs. Multiple studies have consistently shown that the final destination of most EPs in the water environment is sludge and sediment. Simultaneously, a number of EPs, such as PFASs, MPs, and BFRs, have long-term environmental transport potential. Some EPs exhibit notable tendencies towards bioaccumulation and biomagnification, while others pose challenges in terms of their degradation within both biological and abiotic treatment processes. The results showed that, in most cases, the ecological risk of EPs in aquatic environments was low, possibly due to potential dilution and degradation. Future research topics should include adding EPs detection items for the aquatic environment, combining pollution, and updating prediction models.
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Affiliation(s)
- Yuange Yu
- College of Environment and Ecology, Hunan Agricultural University, Changsha 410128, China
| | - Zhu Wang
- Institute of Environmental Research at Greater Bay/Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China.
| | - Bin Yao
- College of Environment and Ecology, Hunan Agricultural University, Changsha 410128, China
| | - Yaoyu Zhou
- College of Environment and Ecology, Hunan Agricultural University, Changsha 410128, China.
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Ye C, Zhang D, Fang C, Ding J, Duan Y, Chu W. The formation and control of disinfection by-products by two-step chlorination for sewage effluent: Role of organic chloramine decomposition among molecular weight fractions. WATER RESEARCH 2024; 253:121302. [PMID: 38401474 DOI: 10.1016/j.watres.2024.121302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 02/05/2024] [Accepted: 02/10/2024] [Indexed: 02/26/2024]
Abstract
With the increasing discharge of wastewater effluent to natural waters, there is an urgent need to achieve both pathogenic microorganism inactivation and the mitigation of disinfection by-products (DBPs) during disinfection. Studies have shown that two-step chlorination, which injected chlorine disinfectant by splitting into two portions, was more effective in inactivating Escherichia coli than one-step chlorination under same total chlorine consumption and contact time. In this study, we observed a substantial reduction in the formation of five classes of CX3R-type DBPs, especially highly toxic haloacetonitriles (HANs), during two-step chlorination of secondary effluent when the mass ratio of chlorine-to-nitrogen exceeded 2. The shift of different chlorine species (free chlorine, monochloramine and organic chloramine) verified the decomposition of organic chloramines into monochloramine during second chlorination stage. Notably, the organic chloramines generated from the low molecular weight (< 1 kDa) fraction of dissolved organic nitrogen in effluent organic matter tended to decompose during the second step chlorination leading to the mitigation of HAN formation. Furthermore, the microbiological analysis showed that two-step chlorinated effluent had a slightly lower ecological impact on surface water compared to one-step chlorination. This work provided more information about the two-step chlorination for secondary effluent, especially in terms of organic chloramine transformation and HAN control.
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Affiliation(s)
- Cheng Ye
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Key Laboratory of Yangtze River Water Environment, Ministry of Education, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Di Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Key Laboratory of Yangtze River Water Environment, Ministry of Education, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Chao Fang
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Key Laboratory of Yangtze River Water Environment, Ministry of Education, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Jimeng Ding
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Key Laboratory of Yangtze River Water Environment, Ministry of Education, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Youli Duan
- Shanghai Chitech Data Technology Co., Ltd, Shanghai 200092, China
| | - Wenhai Chu
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Key Laboratory of Yangtze River Water Environment, Ministry of Education, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
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5
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Li Z, Yang D, Li S, Yang L, Yan W, Xu H. Advances on electrochemical disinfection research: Mechanisms, influencing factors and applications. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:169043. [PMID: 38070567 DOI: 10.1016/j.scitotenv.2023.169043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 11/26/2023] [Accepted: 11/30/2023] [Indexed: 12/18/2023]
Abstract
Disinfection, a vital barrier against pathogenic microorganisms, is crucial in halting the spread of waterborne diseases. Electrochemical methods have been extensively researched and implemented for the inactivation of pathogenic microorganisms from water and wastewater, primarily owing to their simplicity, efficiency, and eco-friendliness. This review succinctly outlined the core mechanisms of electrochemical disinfection (ED) and systematically examined the factors influencing its efficacy, including anode materials, system conditions, and target species. Additionally, the practical application of ED in water and wastewater treatment was comprehensively reviewed. Case studies involving various scenarios such as drinking water, hospital wastewater, black water, rainwater, and ballast water provided concrete instances of the expansive utility of ED. Finally, coupling ED with other technologies and the resulting synergies were introduced as pivotal foundations for subsequent engineering advancements.
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Affiliation(s)
- Zhen Li
- Department of Environmental Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, China
| | - Duowen Yang
- Department of Environmental Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, China
| | - Shanshan Li
- Department of Environmental Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, China
| | - Liu Yang
- Department of Environmental Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, China
| | - Wei Yan
- Department of Environmental Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, China; Research Institute of Xi'an Jiaotong University, Zhejiang, Hangzhou 311200, China
| | - Hao Xu
- Department of Environmental Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, China; Research Institute of Xi'an Jiaotong University, Zhejiang, Hangzhou 311200, China.
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6
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Lin Y, He Y, Sun Q, Ping Q, Huang M, Wang L, Li Y. Underlying the mechanisms of pathogen inactivation and regrowth in wastewater using peracetic acid-based disinfection processes: A critical review. JOURNAL OF HAZARDOUS MATERIALS 2024; 463:132868. [PMID: 37944231 DOI: 10.1016/j.jhazmat.2023.132868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2023] [Revised: 10/17/2023] [Accepted: 10/24/2023] [Indexed: 11/12/2023]
Abstract
Peracetic acid (PAA) disinfection is an emerging wastewater disinfection process. Its advantages include excellent pathogen inactivation performance and little generation of toxic and harmful disinfection byproducts. The objective of this review is to comprehensively analyze the experimental data and scientific information related to PAA-based disinfection processes. Kinetic models and modeling frameworks are discussed to provide effective tools to assess pathogen inactivation efficacy. Then, the efficacy of PAA-based disinfection processes for pathogen inactivation is summarized, and the inactivation mechanisms involved in disinfection and the interactions of PAA with conventional disinfection processes are elaborated. Subsequently, the risk of pathogen regrowth after PAA-based disinfection process is clearly discussed. Finally, to address ecological risks related to PAA-based disinfection, its impact on the spread of antibiotic-resistant bacteria and the transfer of antibiotic resistance genes (ARGs) is also assessed. Among advanced PAA-based disinfection processes, ultraviolet/PAA is promising not only because it has practical application value but also because pathogen regrowth can be inhibited and ARGs transfer risk can be significantly reduced via this process. This review presents valuable and comprehensive information to provide an in-depth understanding of PAA as an alternative wastewater disinfection technology.
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Affiliation(s)
- Yuqian Lin
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze River Water Environment, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, People's Republic of China
| | - Yunpeng He
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze River Water Environment, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, People's Republic of China
| | - Qiya Sun
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze River Water Environment, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, People's Republic of China
| | - Qian Ping
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze River Water Environment, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, People's Republic of China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, People's Republic of China
| | - Manhong Huang
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, People's Republic of China; Textile Pollution Controlling Engineering Center of Ministry of Environmental Protection, College of Environmental Science and Engineering, Donghua University, Shanghai 201620, People's Republic of China
| | - Lin Wang
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze River Water Environment, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, People's Republic of China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, People's Republic of China.
| | - Yongmei Li
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze River Water Environment, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, People's Republic of China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, People's Republic of China
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7
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Parveen N, Mondal P, Vanapalli KR, Das A, Goel S. Phytotoxicity of trihalomethanes and trichloroacetic acid on Vigna radiata and Allium cepa plant models. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:5100-5115. [PMID: 38110686 DOI: 10.1007/s11356-023-31419-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2023] [Accepted: 12/04/2023] [Indexed: 12/20/2023]
Abstract
Disinfection by-products (DBPs) are a concern due to their presence in chlorinated wastewater, sewage treatment plant discharge, and surface water, and their potential for environmental toxicity. Despite some attention to their ecotoxicity, little is known about the phytotoxicity of DBPs. This study aimed to evaluate the individual and combined phytotoxicity of four trihalomethanes (THMs: trichloromethane (TCM), bromodichloromethane (BDCM), dibromochloromethane (DBCM), and tribromomethane (TBM) and their mixture (THM4)), and trichloroacetic acid (TCAA) using genotoxic and cytotoxic assays. The analysis included seed germination tests using Vigna radiata and root growth tests, mitosis studies, oxidative stress response, chromosomal aberrations (CA), and DNA laddering using Allium cepa. The results showed a progressive increase in root growth inhibition for both plant species as the concentration of DBPs increased. High concentrations of mixtures of four THMs resulted in significant (p < 0.05) antagonistic interactions. The effective concentration (EC50) value for V. radiata was 5655, 3145, 2690, 1465, 3570, and 725 mg/L for TCM, BDCM, DBCM, TBM, THM4, and TCAA, respectively. For A. cepa, the EC50 for the same contaminants was 700, 400, 350, 250, 450, and 105 mg/L, respectively. DBP cytotoxicity was observed through CAs, including C-metaphase, unseparated anaphase, lagging chromosome, sticky metaphase, and bridging. Mitotic depression (MD) increased with dose, reaching up to 54.4% for TCAA (50-500 mg/L). The electrophoresis assay showed DNA fragmentation and shearing, suggesting genotoxicity for some DBPs. The order of phytotoxicity for the tested DBPs was TCAA > TBM > DBCM > BDCM > THM4 > TCM. These findings underscore the need for further research on the phytotoxicity of DBPs, especially given their common use in agricultural practices such as irrigation and the use of sludge as manure.
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Affiliation(s)
- Naseeba Parveen
- School of Environmental Science and Engineering, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, 721302, India
- Department of Civil Engineering, National Institute of Technology Mizoram, Aizawl, Mizoram, 796012, India
| | - Papiya Mondal
- School of Bioscience, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, 721302, India
| | - Kumar Raja Vanapalli
- School of Environmental Science and Engineering, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, 721302, India.
- Department of Civil Engineering, National Institute of Technology Mizoram, Aizawl, Mizoram, 796012, India.
| | - Abhijit Das
- School of Bioscience, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, 721302, India
| | - Sudha Goel
- School of Environmental Science and Engineering, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, 721302, India
- Department of Civil Engineering, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, 721302, India
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Gao J, Chen G, Fu Q, Ren C, Tan C, Liu H, Wang Y, Liu J. Enhancing Aqueous Chlorate Reduction Using Vanadium Redox Cycles and pH Control. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:20392-20399. [PMID: 37976223 DOI: 10.1021/acs.est.3c06519] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2023]
Abstract
Chlorate (ClO3-) is a toxic oxyanion pollutant from industrial wastes, agricultural applications, drinking water disinfection, and wastewater treatment. Catalytic reduction of ClO3- using palladium (Pd) nanoparticle catalysts exhibited sluggish kinetics. This work demonstrates an 18-fold activity enhancement by integrating earth-abundant vanadium (V) into the common Pd/C catalyst. X-ray photoelectron spectroscopy and electrochemical studies indicated that VV and VIV precursors are reduced to VIII in the aqueous phase (rather than immobilized on the carbon support) by Pd-activated H2. The VIII/IV redox cycle is the predominant mechanism for the ClO3- reduction. Further reduction of chlorine intermediates to Cl- could proceed via VIII/IV and VIV/V redox cycles or direct reduction by Pd/C. To capture the potentially toxic V metal from the treated solution, we adjusted the pH from 3 to 8 after the reaction, which completely immobilized VIII onto Pd/C for catalyst recycling. The enhanced performance of reductive catalysis using a Group 5 metal adds to the diversity of transition metals (e.g., Cr, Mo, Re, Fe, and Ru in Groups 6-8) for water pollutant treatment via various unique mechanisms.
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Affiliation(s)
- Jinyu Gao
- Department of Chemical and Environmental Engineering, University of California, Riverside, California 92521, United States
| | - Gongde Chen
- Department of Chemical and Environmental Engineering, University of California, Riverside, California 92521, United States
| | - Qi Fu
- Department of Chemical and Environmental Engineering, University of California, Riverside, California 92521, United States
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry/KLGHEI of Environment and Energy Chemistry, School of Chemistry, Sun Yat-Sen University, Guangzhou, Guangdong 510275, China
| | - Changxu Ren
- Department of Chemical and Environmental Engineering, University of California, Riverside, California 92521, United States
| | - Cheng Tan
- Department of Chemical and Environmental Engineering, University of California, Riverside, California 92521, United States
| | - Haizhou Liu
- Department of Chemical and Environmental Engineering, University of California, Riverside, California 92521, United States
| | - Yin Wang
- Department of Civil and Environmental Engineering, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201, United States
| | - Jinyong Liu
- Department of Chemical and Environmental Engineering, University of California, Riverside, California 92521, United States
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Xue B, Guo X, Cao J, Yang S, Qiu Z, Wang J, Shen Z. The occurrence, ecological risk, and control of disinfection by-products from intensified wastewater disinfection during the COVID-19 pandemic. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 900:165602. [PMID: 37478942 DOI: 10.1016/j.scitotenv.2023.165602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 07/13/2023] [Accepted: 07/15/2023] [Indexed: 07/23/2023]
Abstract
Increased disinfection of wastewater to preserve its microbiological quality during the coronavirus infectious disease-2019 (COVID-19) pandemic have inevitably led to increased production of toxic disinfection by-products (DBPs). However, there is limited information on such DBPs (i.e., trihalomethanes, haloacetic acids, nitrosamines, and haloacetonitriles). This review focused on the upsurge of chlorine-based disinfectants (such as chlorine, chloramine and chlorine dioxide) in wastewater treatment plants (WWTPs) in the global response to COVID-19. The formation and distribution of DBPs in wastewater were then analyzed to understand the impacts of these large-scale usage of disinfectants in WWTPs. In addition, potential ecological risks associated with DBPs derived from wastewater disinfection and its receiving water bodies were summarized. Finally, various approaches for mitigating DBP levels in wastewater and suggestions for further research into the environmental risks of increased wastewater disinfection were provided. Overall, this study presented a comprehensive overview of the formation, distribution, potential ecological risks, and mitigating approaches of DBPs derived from wastewater disinfection that will facilitate appropriate wastewater disinfection techniques selection, potential ecological risk assessment, and removal approaches and regulations consideration.
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Affiliation(s)
- Bin Xue
- Tianjin Institute of Environmental and Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment and Food Safety, Tianjin, 300050, China
| | - Xuan Guo
- State Key Laboratory of NBC Protection for Civilian, Research Institute of Chemical Defense, Academy of Military Science, Beijing 102205, China
| | - Jinrui Cao
- Tianjin Institute of Environmental and Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment and Food Safety, Tianjin, 300050, China
| | - Shuran Yang
- Tianjin Institute of Environmental and Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment and Food Safety, Tianjin, 300050, China
| | - Zhigang Qiu
- Tianjin Institute of Environmental and Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment and Food Safety, Tianjin, 300050, China
| | - Jingfeng Wang
- Tianjin Institute of Environmental and Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment and Food Safety, Tianjin, 300050, China.
| | - Zhiqiang Shen
- Tianjin Institute of Environmental and Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment and Food Safety, Tianjin, 300050, China.
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Shekhawat SS, Saini P, Upadhyay A, Pareek N, Arora S, Gupta AB, Vivekanand V. Treatment of clinical laboratory sewage using a decentralized treatment unit and risk reduction for its reuse in irrigation using hybrid disinfection. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 344:118684. [PMID: 37536236 DOI: 10.1016/j.jenvman.2023.118684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 06/08/2023] [Accepted: 07/25/2023] [Indexed: 08/05/2023]
Abstract
The disinfection efficacy of standalone chlorine, UV and their combined approach (hybrid) was investigated for the coliform removal in BioKube 1 and 2 treated effluents collected from different environmental settings of clinical and domestic wastes. Chlorine and UV disinfection were applied to BioKube treated wastewater with doses from 0 to 4 mg L-1 and 0-166 mJ cm-2 respectively. Combined disinfection strategies were designed to reduce the dose of chlorine and UV and to exploit the synergistic effect of them. The culturable coliforms were enumerated in treated wastewater sample (control), immediately after (reduction), and 24 h post disinfections (regrowth) using culture media plating and colilert-18 media. Both the BioKube systems (1 and 2) were effective in achieving the strict norms of physicochemical parameters, but not following the coliform counts of treated effluent for reuse in irrigation. A hybrid strategy of chlorine followed by UV was found to be the most effective among various standalone and combination approaches for the removal of coliforms (>4 log ER or <1000 CFU/100 mL) from both the treated effluents. However, coliform present in treated effluent of BioKube 1 were resisting (regrowth) against all kind of applied disinfectants except chlorine followed by UV dose at or more than 0.5 mg L-1 + 41 mJ cm-2. Limited reports are available on hybrid disinfection approaches with decentralized packaged sewage treatment units and this study would help to adopt as an effective tertiary treatment strategy for reuse of treated sewage for irrigation while ensuring public health safety.
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Affiliation(s)
- Sandeep Singh Shekhawat
- Centre for Energy and Environment, Malaviya National Institute of Technology Jaipur, JLN Marg, Jaipur, 302017, India; Department of Mechanical-Mechatronics Engineering, The LNM Institute of Information Technology, Jaipur, 302031, India
| | - Pankaj Saini
- Department of Civil Engineering, Malaviya National Institute of Technology Jaipur, JLN Marg, Jaipur, 302017, India
| | - Aparna Upadhyay
- Department of Civil Engineering, Malaviya National Institute of Technology Jaipur, JLN Marg, Jaipur, 302017, India
| | - Nidhi Pareek
- Department of Microbiology, School of Life Sciences, Central University of Rajasthan Bandarsindri, Ajmer, Kishangarh, Rajasthan, 305801, India
| | - Sudipti Arora
- B. Lal Institute of Biotechnology, Jaipur, Rajasthan 302017, India
| | - Akhilendra Bhushan Gupta
- Department of Civil Engineering, Malaviya National Institute of Technology Jaipur, JLN Marg, Jaipur, 302017, India
| | - Vivekanand Vivekanand
- Centre for Energy and Environment, Malaviya National Institute of Technology Jaipur, JLN Marg, Jaipur, 302017, India.
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11
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Li H, Dechesne A, He Z, Jensen MM, Song HL, Smets BF. Electrochemical disinfection may increase the spread of antibiotic resistance genes by promoting conjugal plasmid transfer. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 858:159846. [PMID: 36328265 DOI: 10.1016/j.scitotenv.2022.159846] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 10/25/2022] [Accepted: 10/27/2022] [Indexed: 06/16/2023]
Abstract
Current in the milliampere range can be used for electrochemical inactivation of bacteria. Yet, bacteria-including antibiotic resistant bacteria (ARB) may be subjected to sublethal conditions due to imperfect mixing or energy savings measures during electrochemical disinfection. It is not known whether such sublethal current intensities have the potential to stimulate plasmid transfer from ARB. In this study, conjugal transfer of plasmid pKJK5 was investigated between Pseudomonas putida strains under conditions reflecting electrochemical disinfection. Although the abundance of culturable and membrane-intact donor and recipient cells decreased with applied current (0-60 mA), both transconjugant density and transconjugant frequency increased. Both active chlorine and superoxide radicals were generated electrolytically, and ROS generation was induced. In addition, we detected significant over expression of a core oxidative stress defense gene (ahpCF) with current. Expression of selected conjugation related genes (traE, traI, trbJ, and trbL) also significantly correlated with current intensity. ROS accumulation, SOS response and subsequent derepression of conjugation are therefore the plausible consequence of sublethal current exposure. These findings suggest that sublethal intensities of current can enhance conjugal plasmid transfer, and that it is essential that conditions of electrochemical disinfection (applied voltage, current density, time and mixing) are carefully controlled to avoid conjugal ARG transmission.
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Affiliation(s)
- Hua Li
- College of Urban Construction, Nanjing Tech University, Nanjing 211816, China; Department of Environmental and Resource Engineering, Technical University of Denmark, Kgs Lyngby 2800, Denmark
| | - Arnaud Dechesne
- Department of Environmental and Resource Engineering, Technical University of Denmark, Kgs Lyngby 2800, Denmark.
| | - Zhiming He
- Department of Environmental and Resource Engineering, Technical University of Denmark, Kgs Lyngby 2800, Denmark.
| | - Marlene Mark Jensen
- Department of Environmental and Resource Engineering, Technical University of Denmark, Kgs Lyngby 2800, Denmark.
| | - Hai Liang Song
- School of Environment, Jiangsu Engineering Lab of Water and Soil Eco-remediation, Jiangsu Province Engineering Research Center of Environmental Risk Prevention and Emergency Response Technology, Nanjing Normal University, Wenyuan Road 1, Nanjing 210023, China.
| | - Barth F Smets
- Department of Environmental and Resource Engineering, Technical University of Denmark, Kgs Lyngby 2800, Denmark.
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12
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Li X, Yang H, Pan J, Liu T, Cao X, Ma H, Wang X, Wang YF, Wang Y, Lu S, Tian J, Gao L, Zheng X. Variation of the toxicity caused by key contaminants in industrial wastewater along the treatment train of Fenton-activated sludge-advanced oxidation processes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 858:159856. [PMID: 36374753 DOI: 10.1016/j.scitotenv.2022.159856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 10/16/2022] [Accepted: 10/27/2022] [Indexed: 06/16/2023]
Abstract
Industrial wastewater contains a mixture of refractory and hazardous pollutants that have comprehensive toxic effects. We investigated the treatment of a long-chain industrial wastewater treatment train containing Fenton, biological anoxic/oxic (AO), and heterogeneous ozone catalytic oxidation (HOCO) processes, and evaluated their detoxification effect based on the analysis of the genic toxicity of some key contaminants. The results showed that although the effluent met the discharge standard in terms of traditional quality parameters, the long-chain treatment process could not effectively detoxify the industrial wastewater. The analysis results of summer samples showed that the Fenton process increased the total toxicity and genotoxicity of the organics, concerned metals, and non-volatile pollutants, whereas the A/O process increased the toxicity of the organics and non-volatile pollutants, and the HOCO process led to higher toxicity caused by metals and non-volatile pollutants. The outputs of the winter samples indicated that the Fenton process reduced the total toxicity and genotoxicity caused by non-volatile pollutants but increased that of the organics and concerned metals. The effect of the A/O process on the effluent toxicity in winter was the same as that in summer, whereas the HOCO process increased the total toxicity and genotoxicity of the metals in winter samples. Correlation analysis showed that various toxicity stresses were significantly correlated with the variation of these key pollutants in wastewater. Our results could provide a reference for the optimization of industrial wastewater treatment plants (IWTPs) by selecting more suitable treatment procedures to reduce the toxicity of different contaminants.
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Affiliation(s)
- Xiaolin Li
- State Key Laboratory of Eco-Hydraulics in North West Arid Region of China, Xi'an University of Technology, Xi'an 710048, China
| | - Heyun Yang
- State Key Laboratory of Eco-Hydraulics in North West Arid Region of China, Xi'an University of Technology, Xi'an 710048, China
| | - Jian Pan
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Tong Liu
- State Key Laboratory of Eco-Hydraulics in North West Arid Region of China, Xi'an University of Technology, Xi'an 710048, China
| | - Xin Cao
- State Key Laboratory of Eco-Hydraulics in North West Arid Region of China, Xi'an University of Technology, Xi'an 710048, China
| | - Hao Ma
- State Key Laboratory of Eco-Hydraulics in North West Arid Region of China, Xi'an University of Technology, Xi'an 710048, China
| | - Xingliang Wang
- State Key Laboratory of Eco-Hydraulics in North West Arid Region of China, Xi'an University of Technology, Xi'an 710048, China
| | - Yi-Fan Wang
- State Key Laboratory of Eco-Hydraulics in North West Arid Region of China, Xi'an University of Technology, Xi'an 710048, China
| | - Yifan Wang
- State Key Laboratory of Eco-Hydraulics in North West Arid Region of China, Xi'an University of Technology, Xi'an 710048, China
| | - Sijia Lu
- State Key Laboratory of Eco-Hydraulics in North West Arid Region of China, Xi'an University of Technology, Xi'an 710048, China
| | - Jiayu Tian
- School of Civil and Transportation Engineering, Hebei University of Technology, Tianjin 300401, China
| | - Lei Gao
- State Key Laboratory of Eco-Hydraulics in North West Arid Region of China, Xi'an University of Technology, Xi'an 710048, China
| | - Xing Zheng
- State Key Laboratory of Eco-Hydraulics in North West Arid Region of China, Xi'an University of Technology, Xi'an 710048, China; Resource Recovery and Low-carbon Environmental Protection Engineering Center in Coal Chemical Industry, Yulin, Shaanxi, China.
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13
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Hsieh CY, Wu YC, Mudigonda S, Dahms HU, Wu MC. Assessing the Effects of Ozonation on the Concentrations of Personal Care Products and Acute Toxicity in Sludges of Wastewater Treatment Plants. TOXICS 2023; 11:75. [PMID: 36668801 PMCID: PMC9865304 DOI: 10.3390/toxics11010075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 12/27/2022] [Accepted: 01/06/2023] [Indexed: 06/17/2023]
Abstract
The aim of this study was to understand the distribution of the personal care products nonylphenol (NP), triclosan (TCS), benzophenone-3 (BP-3), and caffeine in the sludges from three wastewater treatment plants (WWTP-A, -B, and -C) in southern Taiwan. The four compounds were analyzed from activated sludge and dewatered sludge samples, and then the samples were treated with pressure-assisted ozonation under different conditions and removal efficiencies. All four target compounds were detected, especially NP, which was detected in the highest concentrations in the activated sludges of WWTP-A and dewatered sludges of WWTP-C at 17.19 ± 4.10 and 2.41 ± 1.93 µg/g, respectively. TCS was dominant in dewatered sludges from WWTP-B, and the highest detected concentration was 13.29 ± 6.36 µg/g. Removals of 70% and 90% were attained under 150 psi at 40 cycles for NP and TCS, respectively, with 5 min of ozonation reaction time, a solid/water ratio of 1:20, and 2% ozone concentration. Ecological risk quotients (RQs) were calculated by the ratios of the 10-day Hyalella azteca (freshwater amphipod) LC50 to the environmental concentrations of the target compounds. High RQs were found to be >10 for NP, TCS, and BP-3 in untreated sludges, resulting in significant ecological risks to aquatic organisms when the sludges are arbitrarily disposed. However, the toxic effects on Hyalella azteca were not significantly different among ozone sludge treatments. The reason for this may be related to the formation of toxic oxidation by-products and incomplete mineralization of organic compounds. This could also be true for unknown intermediates. The relatively high detection frequencies of these emerging compounds in WWTP sludges requires further applications and treatments.
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Affiliation(s)
- Chi-Ying Hsieh
- Department of Environmental Science and Engineering, National Pingtung University of Science and Technology, Pingtung 912, Taiwan
- Center for Water Resources Education and Research, National Pingtung University of Science and Technology, Pingtung 912, Taiwan
- Department of Biomedical Science and Environmental Biology, Kaohsiung Medical University, Kaohsiung City 80708, Taiwan
| | - Ya-Chin Wu
- Department of Environmental Science and Engineering, National Pingtung University of Science and Technology, Pingtung 912, Taiwan
| | - Sunaina Mudigonda
- Department of Biomedical Science and Environmental Biology, Kaohsiung Medical University, Kaohsiung City 80708, Taiwan
- Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung City 807, Taiwan
| | - Hans-Uwe Dahms
- Department of Environmental Science and Engineering, National Pingtung University of Science and Technology, Pingtung 912, Taiwan
- Department of Biomedical Science and Environmental Biology, Kaohsiung Medical University, Kaohsiung City 80708, Taiwan
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung 80424, Taiwan
- Research Center for Precision Environmental Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Meng-Chun Wu
- Department of Environmental Science and Engineering, National Pingtung University of Science and Technology, Pingtung 912, Taiwan
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14
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Application of O3/PMS Advanced Oxidation Technology in the Treatment of Organic Pollutants in Highly Concentrated Organic Wastewater: A Review. SEPARATIONS 2022. [DOI: 10.3390/separations9120444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The ozone/peroxymonosulfate (O3/PMS) system has attracted widespread attention from researchers owing to its ability to produce hydroxyl radicals (•OH) and sulfate radicals (SO4•−) simultaneously. The existing research has shown that the O3/PMS system significantly degrades refinery trace organic compounds (TrOCs) in highly concentrated organic wastewater. However, there is still a lack of systematic understanding of the O3/PMS system, which has created a significant loophole in its application in the treatment of highly concentrated organic wastewater. Hence, this paper reviewed the specific degradation effect, toxicity change, reaction mechanism, various influencing factors and the cause of oxidation byproducts (OBPs) of various TrOCs when the O3/PMS system is applied to the degradation of highly concentrated organic wastewater. In addition, the effects of different reaction conditions on the O3/PMS system were comprehensively evaluated. Furthermore, given the limited understanding of the O3/PMS system in the degradation of TrOCs and the formation of OBPs, an outlook on potential future research was presented. Finally, this paper comprehensively evaluated the degradation of TrOCs in highly concentrated organic wastewater by the O3/PMS system, filling the gaps in scale research, operation cost, sustainability and overall feasibility.
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15
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Tertiary Wastewater Treatment Technologies: A Review of Technical, Economic, and Life Cycle Aspects. Processes (Basel) 2022. [DOI: 10.3390/pr10112304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The activated sludge process is the most widespread sewage treatment method. It typically consists of a pretreatment step, followed by a primary settling tank, an aerobic degradation process, and, finally, a secondary settling tank. The secondary effluent is then usually chlorinated and discharged to a water body. Tertiary treatment aims at improving the characteristics of the secondary effluent to facilitate its reuse. In this work, through a literature review of the most prominent tertiary treatment methods, a benchmarking of their technical efficiency, economic feasibility, and environmental impact was carried out. The photo-Fenton method proved to be the most technically efficient process, significantly reducing the microbial load and pharmaceutical content (by 4.9 log and 84%, respectively) of the secondary effluent. Chlorination and UV irradiation exhibited the lowest treatment costs (0.004 EUR/m−3) and the lowest global warming potential (0.04 and 0.09 kg CO2eq. m−3, respectively). After all the data were aggregated, a decision-making tool was constructed in the form of a ternary diagram, which indicates the most appropriate tertiary treatment method according to the weight-per-process aspect (technical, economic, and environmental) selected by the user, with chlorination, UV irradiation, ozonation, microalgae cultivation, and constructed wetlands prevailing in the final results.
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16
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Saravanan A, Kumar PS, Rangasamy G. Removal of Toxic Pollutants from Industrial Effluent: Sustainable Approach and Recent Advances in Metal Organic Framework. Ind Eng Chem Res 2022. [DOI: 10.1021/acs.iecr.2c02945] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/17/2023]
Affiliation(s)
- Anbalagan Saravanan
- Department of Sustainable Engineering, Institute of Biotechnology, Saveetha School of Engineering, SIMATS, Chennai−602105, India
| | - Ponnusamy Senthil Kumar
- Department of Chemical Engineering, Sri Sivasubramaniya Nadar College of Engineering, Chennai−603110, India
- Centre of Excellence in Water Research (CEWAR), Sri Sivasubramaniya Nadar College of Engineering, Chennai−603110, India
| | - Gayathri Rangasamy
- University Centre for Research and Development & Department of Civil Engineering, Chandigarh University, Gharuan, Mohali, Punjab−140413, India
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17
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Study on the Disinfection Efficiency of the Combined Process of Ultraviolet and Sodium Hypochlorite on the Secondary Effluent of the Sewage Treatment Plant. Processes (Basel) 2022. [DOI: 10.3390/pr10081622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The combined disinfection process of ultraviolet and sodium hypochlorite has more advantages than the single disinfection method in reducing the disinfectant dosage, shortening the reaction time, and resisting the impact of water quality changes and inhibiting the light reactivation of microorganisms. Given this, using the secondary effluent of a sewage plant as the research object, the disinfection efficiency of the combined process of ultraviolet and sodium hypochlorite was investigated. The experimental results showed that the inactivation effect of UV followed by sodium hypochlorite on fecal coliform and the inhibition of microbial photoreactivation was more significant than that of simultaneous disinfection of UV and sodium hypochlorite disinfection. When the UV dose was 24 mJ/cm2, after disinfection with UV followed by sodium hypochlorite, only 1 mg/L of sodium hypochlorite was required to be added, and a contact reaction time of 1 min for the fecal coliform index to meet the first-Class A emission standard. After disinfection, the effluent’s maximum reactivation rate of fecal coliform was 26.96%. However, the simultaneous disinfection of ultraviolet and sodium hypochlorite required the addition of 3 mg/L of sodium hypochlorite. After disinfection, the maximum reactivation rate of the fecal coliform group reached 30.81%.
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18
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Sustainability Assessment for Wastewater Treatment Systems in Developing Countries. WATER 2022. [DOI: 10.3390/w14020241] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
As the assessment of the economic, environmental, institutional, and social sustainability of wastewater treatment systems may have several conceivable goals and intended recipients, there are numerous different approaches. This paper surveys certain aspects of sustainability assessment that may be of interest to the planners of wastewater treatment systems. Here, the key criteria assess the system’s costs and financing, including its affordability for the users, the environmental impact, the benefits for health and hygiene, the cultural acceptance of the system and its recycled products, the technical functioning, and the administrative, political, and legal framework for its construction and operation. A multi-criteria approach may then be used to analyze possible trade-offs and identify the most suitable system for a certain location.
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