Parallel factor analysis of fluorescence excitation emissions to identify seasonal and watershed differences in trihalomethane precursors
Autor: | Watsa Khongnakorn, Watjanee Laolertworakul, Suchat Leungprasert, Panitan Jutaporn, Kitiyot Tungsudjawong |
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Rok vydání: | 2021 |
Předmět: |
Environmental Engineering
Health Toxicology and Mutagenesis media_common.quotation_subject 0208 environmental biotechnology 02 engineering and technology 010501 environmental sciences 01 natural sciences Fluorescence spectroscopy Water Purification chemistry.chemical_compound Dissolved organic carbon Environmental Chemistry Chemical composition Humic Substances 0105 earth and related environmental sciences media_common Chemistry Public Health Environmental and Occupational Health General Medicine General Chemistry Thailand Pollution 020801 environmental engineering Trihalomethane Speciation Spectrometry Fluorescence Environmental chemistry Water treatment Water quality Seasons Factor Analysis Statistical Surface water Trihalomethanes |
Zdroj: | Chemosphere. 282 |
ISSN: | 1879-1298 |
Popis: | Concentration and chemical composition of dissolved organic matter (DOM) play a major role in formation and speciation of disinfection by-products, such as trihalomethanes (THMs), in water treatment plants (WTPs) during disinfection. This study characterized DOM across the process trains of WTPs using fluorescence excitation emission matrices (EEMs) together with parallel factor analysis (PARAFAC). The PARAFAC model was developed from 216 EEMs of bimonthly water samples from three WTPs in Khon Kaen, Thailand, from May 2018 to Mar 2019. Three PARAFAC components identified were humic-like DOM of terrestrial, and microbial or agricultural origin, while the one protein-like component was previously defined as tryptophan-like fluorophore. The relationships between water quality parameters, including the maximum fluorescent intensities (Fmax) of PARAFAC components and THM formation potential (THM-FP) were investigated using Spearman's rank correlation. The Fmax of PARAFAC components, UVA254, DOC, and THM-FP were greater in dry season. Chloroform was the primary THM formed at two sites using surface water as their water source, while the site using surface water with saline groundwater intrusion had higher concentration of brominated THMs. Results indicated that Fmax of humic-like components extracted by PARAFAC analysis were the most accurate THM-FP surrogate parameter assessed for the water samples tested and the correlations between Fmax and THM-FP were site specific (ρ = 0.81–0.85). The result demonstrates that fluorescence spectroscopy analysis has yielded insights into relationships between the DOM optical characteristics and their total THM-FP even at sites with different speciation of THMs. |
Databáze: | OpenAIRE |
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