曝气充氧条件下污染河道氨挥发特性模拟  

Characterization of ammonia volatilization from polluted river under aeration conditons:a simulation study

作　　者：刘波[1,2] 王文林[1,3] 凌芬[1] 王国祥[1] 杜旭[1] 周锋[1] 许宽[1] 夏劲[1] 

机构地区：[1]南京师范大学地理科学学院,南京210046 [2]南通大学地理科学学院,南通226007 [3]环境保护部南京环境科学研究所,南京210042

出　　处：《生态学报》2012年第23期7270-7279,共10页Acta Ecologica Sinica

基　　金：国家自然基金项目(41173078);环境保护部南京环境科学研究所中央公益性科研院所基本科研业务专项(2012-11);江苏省太湖水环境治理专项基金(TH2010303;TH2011207);江苏省建设系统科技项目(JS2011JH25)

摘　　要：以污染河道为研究对象,模拟研究污染河道在曝气充氧(底泥曝气,ES组;水曝气,EW组)条件下氨挥发的特性,探讨主要影响因素及其作用过程。研究表明,污染河道水体具有一定氨挥发潜力,在实验室模拟条件下,氨挥发速率平均为2.51mg.m-2.h-1,相当于0.50 kgN.hm-.2d-1;曝气污染河道水体的氨挥发有一定的促进作用,与对照相比(EC组)氨挥发速率和累积氨挥发量存在显著差异(P<0.05);不同曝气方式对氨挥发过程影响不同,氨挥发速率存在显著差异(P<0.05);至实验结束,EW组的累积挥发量为2809.76 mg/m2,分别是ES组和EC组的1.17和2.25倍;各实验组的氨挥发累积量用一级动力学方程能很好地拟合,根据模型可以预测氨挥发量;同一温度条件下,pH值、铵氮浓度和通气频率是影响氨挥发的主要因素;曝气可以通过增加通气频率和提高水体pH值来促进氨挥发进行;在曝气作用下随着硝化过程的进行对氨挥发有一定的限制作用;曝气条件下,氨挥发作用在硝化过程启动阶段最为明显。Most surface waters in China are eutrophic because of anthropogenic activities. Eutrophication typically results in algal blooms and can lead to poor water quality. Nitrogen is generally recognized as one of the most influential nutrients limiting productivity within an aquatic ecosystem. Nitrogen is also is one of the main factors affecting water quality. The main reason for this phenomenon is that various organic materials including nitrogen-rich materials that exist widely in the water column and sediments consume oxygen, resulting in a lack of dissolved oxygen. Artificial aeration is a technique used to improve water quality of polluted rivers and is widely used to control river pollution in China and abroad. A large number of studies on aeration have indicated that the nitrification/denitrification pathway is the major reduction mechanism of ammonium nitrogen load within polluted rivers. However, limited information is available on the effect of aeration on ammonia volatilization within urban polluted rivers. Ammonia volatilization is an important pathway facilitating nitrogen removal within aquatic systems. Previous research on characteristics of ammonia volatilization facilitating nitrogen removal from water focused on wastewater with relatively higher concentrations of ammonium. These wastewater types included thoseoriginating from dairies, wastewater containing slurry concentrations, and stabilization ponds treating domestic wastewater. Furthermore, studies evaluating of the role of ammonia volatilization in nitrogen removal from polluted rivers through aeration have yet to be conducted. It is important to conduct research that quantifies the extent of ammonia volatilization within polluted urban rivers under different aeration conditions. This knowledge can indicate the extent of nitrogen removal by different widely applied techniques for treating heavily polluted river water. Characteristics of ammonia volatilization within a polluted urban river under different conditions were examined： aerating to

关 键 词：氨挥发 曝气方式 PH 硝化作用 污染河道 

分 类 号：X522[环境科学与工程—环境工程]