• 关键词：驯化活性污泥  丙烯酰胺  动力学方程  生物降解

• 基金项目：

• 李署
• 污染控制与资源化研究国家重点实验室, 南京大学环境学院, 南京 210093

• 孙亚兵
• 污染控制与资源化研究国家重点实验室, 南京大学环境学院, 南京 210093

• 冯景伟
• 污染控制与资源化研究国家重点实验室, 南京大学环境学院, 南京 210093

• 田园春
• 污染控制与资源化研究国家重点实验室, 南京大学环境学院, 南京 210093

• 徐跃武
• 污染控制与资源化研究国家重点实验室, 南京大学环境学院, 南京 210093

• 杨海峰
• 污染控制与资源化研究国家重点实验室, 南京大学环境学院, 南京 210093

• 摘要：对好氧活性污泥进行驯化,并研究了丙烯酰胺的生物降解动力学特征.驯化结果表明,经过24d的驯化后,活性污泥系统能稳定降解AM,驯化活性污泥能在20h内降解90%以上的AM,是高效的丙烯酰胺降解菌群.驯化活性污泥对丙烯酰胺的降解符合一级动力学特征.活性污泥对初始浓度为160、300和500mg·L^-1浓度范围内的降解动力学方程分别为lnS=-0.0881t+5.5043,lnS=-0.0692t+6.1282,lnS=-0.0468t+6.3649,半衰期t_1/2分别为7.87h,10.05h,14.87h,降解速率常数K_b随着AM浓度增加而降低,说明高浓度的AM对其生物降解有抑制作用.当pH分别为8.5,7.2,6.2,5.1时,活性污泥对初始浓度为300mg·L^-1的AM的降解动力学方程分别为lnS=-0.0414t+6.1038,lnS=-0.0592t+6.1744,lnS=-0.0692t+6.1282,lnS=-0.06t+6.1282,半衰期分别为16.74h、11.71h、10.05h、11.55h,说明弱酸性条件对AM的降解有明显的促进作用.考察温度对活性污泥降解动力学影响的研究表明,在20～35℃,随着温度的升高,活性污泥对AM的降解效率上升.不同时间段体系内NH₄⁺-N、pH和NO₃^--N都随着降解时间的增加逐步上升,但是达到一定时间后会下降,表明AM在降解过程中先水解,然后发生硝化反应,进而发生反硝化反应,最终AM降解成N₂、CO₂和H₂O.

• Abstract：Activated sludge was acclimated to acrylamide(AM)and the kinetics of AM biodegradation was studied.It was demonstrated that the acclimated activated sludge could degrade AM steadily and was a high efficiency flora for degrading AM,able to degrade more than 90% AM in 20 hours.The degradation of AM could be described by a first-order kinetics model.For AMconcentrations of 160,300,and 500 mg·L^-1,the kinetics equations of degradation were lnS=-0.0881t+5.5043,lnS=-0.0692t+6.1282,and lnS=-0.0468t+6.3649,and the t_1/2 were 7.87 h,10.05 h,and 14.87 h,respectively.The rate constant of degradation decreased as the concentration of AM increased,which showed that high concentrations of AM inhibited the biodegradation.In addition,when the concentration of AM was 300 mg·L^-1,and the pHof the system was 8.5,7.2,6.2,or 5.1,the kinetics equations of degradation were lnS=-0.0414t+6.1038,lnS=-0.0592t+6.1744,lnS=-0.0692t+6.1282,and lnS=-0.06t+6.1282,and t_1/2 were 16.74 h,11.71 h,10.05 h and 11.55 h,which demonstrated that weak acid conditions could promote the biodegradation more effectively than weak alkaline conditions.The results also demonstrated that in the range of 20～35℃,the biodegradation efficiency increased as the temperature increased.The concentrations of NH₄⁺-N,pH and NO₃^--N first increased,but later they decreased smoothly.During the biodegradation process,AMwas first hydrolyzed,then nitrified and denitrified,and the final products were oxidized into N₂,CO₂ and H₂O.

• Key words：acclimated activated sludge  acrylamide  kinetics  biodegradation

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