The objective of this pilot-scale study was to investigate the effectiveness of incorporating ozone (O) and advanced oxidation (hydrogen peroxide/ozone: HO/O) in combination with biofiltration for taste and odour control, organic carbon removal, and disinfection byproduct (DBP) precursor reduction. Implementation of O and HO/O with and without biofiltration was investigated at pilot-scale in terms of geosmin, 2-methylisoborneol (MIB), and DBP precursor removal efficiency. Two media types (granular activated carbon and anthracite) were compared in conjunction with investigating the impact of pre-oxidation with O (2 mg/L) and varying HO/O mass ratios (0.1, 0.2, 0.35, and 0.5 mg/mg). When O preceded biologically active carbon (BAC) or biologically active anthracite, geosmin removals of 80% and 81%, respectively, were observed at 10 °C; this increased to 89% and 90%, respectively, at 16 °C. Optimal MIB removal (67%) was achieved with 0.1 HO/O (mg/mg) in combination with BAC at 16 °C. In general, geosmin proved to be more amenable to biodegradation than MIB. BAC without pre-oxidation removed 87% geosmin and 85% MIB, at 22 °C. MIB removals decreased to 60% and 46%, respectively at 16 °C and 10 °C. The application of 0.2 HO/O (mg/mg) prior to BAC provided treatment which effectively removed geosmin and MIB. However, in terms of DBP precursor reduction, there was no beneficial impact of HO addition on trihalomethane or haloacetic acid formation potentials.
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http://dx.doi.org/10.1016/j.chemosphere.2018.08.015 | DOI Listing |
Chemosphere
January 2025
University of Chinese Academy of Sciences, Beijing, 100049, China; Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China. Electronic address:
The degradation of rubber seal (RS), particularly ethylene-propylene-diene (EPDM), in the drinking water networks has been confirmed, yet the role of RS as a disinfection by-product (DBP) precursor remains unknown. This study provides explicit proof of the formation of halogenated disinfection by-products (X-DBPs) from RS in chlorinated drinking water within water supply systems. Over time, exposure to chlorinated water ages RS, releasing high levels of organic compounds, which act as DBP precursors.
View Article and Find Full Text PDFSci Total Environ
January 2025
Department of Environmental Engineering, Faculty of Engineering, Khon Kaen University, Khon Kaen 40002, Thailand; Research Center for Environmental and Hazardous Substance Management, Khon Kaen University, Khon Kaen 40002, Thailand. Electronic address:
Chlorine (Cl) and chlorine dioxide (ClO) are commonly used to disinfect water but unfavorable interactions with dissolved organic matter (DOM) result in the formation of disinfection byproducts (DBPs). This study investigated the formation of organic DBPs arising from Cl and ClO disinfections under different contact times in two surface waters in Thailand and Suwannee River natural organic matter with/without bromide using unknown screening analysis with Orbitrap mass spectrometry. Many CHOCl-DBPs and CHOBr-DBPs intermediates were rapidly formed during the initial period of contact (5-30 min).
View Article and Find Full Text PDFWater Res
December 2024
Environmental Research Institute, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China; School of Environment, South China Normal University, University Town, Guangzhou 510006, China.
The formation of disinfection byproducts (DBPs) in drinking water distribution systems (DWDS) is significantly affected by numerous factors, including physicochemical water properties, microbial community composition and structure, and the characteristics of organic DBP precursors. However, the codependence of various factors remains unclear, particularly the contribution of microbial-derived organics to DBP formation, which has been inadequately explored. Herein, we present a Bayesian network modeling framework incorporating a Bayesian-based microbial source tracking method and excitation-emission fluorescence spectroscopy-parallel factor analysis to capture the critical drivers influencing DBP formation and explore their interactions.
View Article and Find Full Text PDFWater Res
December 2024
State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Urban Water Supply, Water Saving and Water Environment Governance in the Yangtze River Delta of Ministry of Water Resources, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, PR China. Electronic address:
Restricted to the complex nature of dissolved organic matter (DOM) in various aquatic environments, the mechanisms of enhanced iodinated disinfection byproducts (I-DBPs) formation in water containing both I and IO (designated as I/IO in this study) during the ultraviolet (UV)-chloramine sequential disinfection process remains unclear. In this study, four machine learning (ML) models were established to predict I-DBP formation by using DOM and disinfection features as input variables. Extreme gradient boosting (XGB) algorithm outperformed the others in model development using synthetic waters and in cross-dataset generalization of surface waters.
View Article and Find Full Text PDFNutrients
November 2024
Postgraduate Program in Movement Sciences, Sao Paulo State University (UNESP), Presidente Prudente 19060-900, SP, Brazil.
Background And Aims: Post-exercise recovery strategies include massage, low-intensity active exercise, thermal contrast, hydration, and nutritional and herbal approaches. These strategies aim to accelerate recovery, enhance performance, and optimise the physical training process. L-arginine (L-ARG) is the physiological precursor of nitric oxide (NO), a crucial mediator of vasodilation and the inhibition of platelet aggregation.
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