湘江底泥对氨氮的吸附动力学研究  

Kinetics study on the adsorption of ammonia nitrogen by Xiangjiang River sediment

作　　者：夏勇锋[1] 何少华[1] 林振波[1] 王丹[1] 皮艾南[1] 

机构地区：[1]南华大学城市建设学院,湖南衡阳421001

出　　处：《安全与环境学报》2015年第2期195-199,共5页Journal of Safety and Environment

摘　　要：为揭示湘江底泥吸附水中氨氮的吸附特性,以湘江底泥为研究对象,通过室内静态吸附试验,分析和探讨了河流底泥吸附水中氨氮的影响因素,并研究了氨氮的吸附动力学特征。结果表明,底泥对氨氮的吸附是复合动力学过程,即吸附初期是快速吸附阶段,此后吸附速率逐渐减小,进入慢速吸附阶段。外界条件的变化对氨氮的吸附量有一定影响,随温度升高或泥水质量比增加,底泥对氨氮的吸附量减少;随氨氮初始质量浓度升高,底泥对氨氮的吸附量增加;在溶液呈酸性(p H<6)时,吸附量随p H值降低而减少,在溶液呈碱性时,吸附量随p H值升高而增大。底泥吸附氨氮过程的动力学试验结果表明,Lagergren准二级动力学模型方程能较好地描述底泥对氨氮的吸附过程。The paper takes it as our research objective to study the sediment of Xiangjiang River in hoping to disclose the characteristics of the sediment in adsorbing ammonia nitrogen in the river water, and in turn to identify the factors that tend to affect the adsorption of am- monia nitrogen by the river sediment. At the same time, our study has also been oriented in the theoretical aspect of the adsorption ki- netics of ammonia nitrogen. The experimental results of ours show that the adsorption of ammonia nitrogen by the sediments is by nature a comprehensive kinetic process, whose initial stage goes up in ad- sorption, and, then, the adsorption rate would be getting to drop continuously, thus, leaving the last adsorption stage a slow one. In addition, the variations in the external conditions, such as pH value, the temperature, the concentration of ammonia nitrogen and the mass ratio of sediment to the sewage may all have a certain effect on the adsorbing capacity of ammonia nitrogen. What is more, with the in- crease of temperature or the mass ratio of sediment to the sewage, it can be expected that the adsorption capacity of ammonia nitrogen is likely to ebb obviously, though, due to the increase of the initial con- centration of ammonia nitrogen, the adsorption capacity of ammonia nitrogen tends to increase. What is more, when the solution is of acidic nature（pH 〈 6）, the adsorption capacity of ammonia nitrogen tends to fall with the decrease of pH value, if the solution is alkaline by nature, the adsorption capacity of ammonia nitrogen tends to in- crease with the increase of pH value. The results of our kinetic exper- iment on the adsorption process of ammonia nitrogen reveal that the intraparticle diffusion model may not be well able to describe the ad- sorption process of ammonia nitrogen by the sediment, and neither will the intraparticulate diffusion be able to control the steps of the adsorption rate. Nevertheless, the adsorption process has been found to better fit Lagergren pseudo-second-order equa

关 键 词：环境工程学 底泥 氨氮 吸附 动力学 

分 类 号：X522[环境科学与工程—环境工程]