| 缺氧活性污泥对17β-雌二醇的吸附与降解研究 |
| 摘要点击 2173 全文点击 1892 投稿时间：2007-12-04 修订日期：2008-01-17 |
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| 中文关键词 17β-雌二醇 缺氧活性污泥 降解 速率常数 吸附 分配系数 |
| 英文关键词 17β-estradiol anoxic activated sludge degradation rate constant adsorption distribution coefficient |
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| 中文摘要 |
| 试验用缺氧活性污泥降解17β-雌二醇，降解过程中，同时测定17β-雌二醇在水相与泥相上的浓度，考察了缺氧活性污泥对17β-雌二醇的吸附等温线与降解动力学，并研究了温度和电子受体NO－3-N浓度对吸附与降解的影响.结果表明，缺氧活性污泥对17β-雌二醇的降解是在泥中进行，水中不直接降解，泥中物质浓度降低后再吸附水中物质，反应是一个动态的吸附降解平衡过程.17β-雌二醇初始浓度为5～15μg/L时，2 h内能完全降解，缺氧降解符合一级反应动力学；降解过程中，17β-雌二醇在缺氧活性污泥上的吸附既符合Freundlich模型又符合线性吸附模型.温度对17β-雌二醇的吸附与降解有很大影响，温度升高反应速率常数增加，但分配系数降低.10、 20、 30℃条件下，其降解速率常数分别为2.411、3.045、3.527 h-1；分配系数kd分别为540.9、460.4、 396.9L/kg.NO-3-N浓度(10～30 mg/L)的变化影响17β-雌二醇的缺氧降解，减少或增加NO-3-N浓度，降解速率常数降低的最大变幅约20%. |
| 英文摘要 |
| Batch experiments were conducted to investigate the sorption isotherms and degradation kinetics of 17β-estradiol (E2) at a low levels (μg/L) by anoxic activated sludge. The effects of temperatures and the concentrations of electron acceptor on the sorption and degradation were also investigated. Results showed that, when the initial concentrations of E2 were 5-15μg/L, E2 was completely degraded after 2 h under anoxic conditions. Anoxic degradation of E2 in the activated sludge can be described by first-order reaction kinetics. During degradation, E2 sorption was well correlated by both Freundlich and linear adsorption isothermal model at different temperatures. The biodegradation behavior was inside the sludge phase. The transfer of the compound between the water phase and the sludge phase followed a linear adsorption isotherm. Temperature exerted significant effects on both the sorption and degradation of E2. The increase of temperature enhanced the E2 biodegradation rate but decreased E2 adsorption capacity on the sludge. The first-order reaction constants for E2 anoxic degradation at the temperatures of 10, 20 and 30℃ were 2.411, 3.045, and 3.527h-1, respectively. The distribution coefficients (kd) were 540.9, 460.4, 396.9L/kg for 10, 20, 30℃, respectively. To some extent, the first-order rate constant of E2 anoxic degradation was infected by NO-3-N concentration (10-30 mg/L). |
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