厌氧与缺氧污泥对17β-雌二醇吸附性能的研究

雌二醇浓度为500～10 000　ng/L,采用活性污泥灭活吸附,考察了吸附平衡时间和pH值对吸附的影响.在10、20、30℃不同温度下建立了Freundlich吸附等温线,并计算了分配系数K_d.结果表明,厌氧与缺氧失活污泥对雌二醇的吸附都在30 min以内达到平衡;pH值在6～9范围内对吸附没有影响,pH大于9时随着pH值增加吸附量减少;两者在不同温度下对雌二醇的吸附都符合Freundlich吸附,都呈线性吸附,分配系数随温度升高而降低,厌氧失活污泥的分配系数K_d为629.2(10℃)＞534.9(20℃)＞405.6(30℃),缺氧失活污泥的分配系数K_d为601.2(10℃)＞491.3(20℃)＞360.1(30℃).另外,研究了厌氧与缺氧活性污泥的吸附等温线与分配系数,厌氧活性污泥的K_d大于缺氧活性污泥.厌氧(缺氧)活性污泥与灭活污泥对雌二醇的吸附未出现明显差别,厌氧污泥的吸附性能强于缺氧污泥.

Adsorption characteristics of 17beta-estradiol to anaerobic and anoxic sludge

Adsorption tests were performed to measure the adsorption capacity of anaerobic and anoxic inactivated sludge for 17beta-estradiol. The effects of pH and temperature were also investigated. The adsorption equilibrium was established in 30 min; no significant pH effect was observed in the pH range of 6-9 at 20 degrees C; when pH >9, the adsorptive capacities decreased with increasing pH value; the adsorptive capacities decreased with increasing temperature. The experimental data of equilibrium concentrations were well correlated by both Freundlich and linear adsorption isothermal models. Distribution coefficients (Kd) decreased with increasing temperature. The distribution coefficients (Kd) of anaerobic inactivated sludge were 629.2 (10 degrees C) > 534.9 (20 degrees C) > 405.6 (30 degrees C), and those of anoxic inactivated sludge were 601.2 (10 degrees C ) > 491.3 (20 degrees C) > 360.1 (30 degrees C). Comparatively, Freundlich parameters K(F), 1/n and Kd of the anaerobic and anoxic activated sludge were measured at 20 degrees C; Distribution coefficient of anoxic activated sludge was lower than that of anaerobic activated sludge. No significant differences were observed between activated and inactivated sludge. The adsorption abilities of anaerobic activated/inactivated sludge were greater than those of anoxic activated/inactivated sludge.