In order to determine the degradation properties of high-concentrated fluvic acid in an ozone system,an effective ozone oxidation method of mild conditions was used to decompose simulated high concentration fulvic acid wastewater.The characteristics and mechanism were investigated by UV-Vis and 3 D-EEM spectra.With initial pH of 8.0 and ozone dosage of 65.00 mg/L,the removal efficiencies of CN,FA and COD reached 82.16％,43.28％ and 26.73％ after 30 min,respectively.When the reaction time was prolonged from 2 to 30 min,the utilization rate of ozone was decreased from 72.52％ to 18.15％.The ratio of B/C (ρ(BOD5)/ρ(CODcr)) was increased from 0.27 to 0.61,and the ρ (HCO3-)was increased from 42.2 to 502.6 mg/L.The results demonstrated that the continuous generation and mineralization of small organic molecules greatly improved the biodegradability of the simulated wastewater.UV-Vis spectra analysis indicated that ozone could increase the concentration of biodegradable substances and simplify the molecular structure of fulvic acid.3D-EEM spectra analysis showed that ozone could effectively degrade fluvic acid-like organic matter and quickly oxidize some small molecule tryptophan.The humification degree of fulvic acid was gradually decreased as the reaction was carried out.%为了解高浓度富里酸在臭氧体系中的降解特性,采用了高效且反应条件温和的臭氧法处理高浓度富里酸模拟废水,并采用紫外-可见吸收光谱和三维荧光光谱,研究了臭氧降解高浓度富里酸的特性与原理.结果表明:在初始pH为8.0、臭氧投加量(以ρ计)为65.00 mg/L的条件下,反应30 min后色度、富里酸、CODCr的去除率分别为82.16％、43.28％、26.73％;臭氧利用率从反应2 min时的72.52％降至30 min时的18.15％,B/C[ρ(BOD5)/ρ(CODCr)]由进水的0.27升至0.61,ρ(HCO3-)由初始的42.2mg/L增至502.6 mg/L,说明小分子有机物的不断生成和矿化使得模拟废水可生化性大幅提高.紫外-可见吸收光谱分析表明,臭氧能使富里酸模拟废水中易降解物质成分增多、富里酸的结构趋于简单.三维荧光光谱表明,臭氧能有效降解大分子富里酸类物质,并较快速地使小分子色氨酸被氧化,随着反应的持续进行,富里酸的腐殖化程度逐渐降低.
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