Vanhooren H, De Pauw D, Vanrolleghem P A
BIOMATH, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium.
Water Sci Technol. 2003;47(11):61-8.
Oxygen transferred from the liquid phase into a biofilm can be used for aerobic degradation of organic matter and for nitrification. A second possible pathway for the removal of organic matter is denitrification in anoxic zones deeper in the biofilm. At high organic loading rates with insufficient oxygen supply to the biofilm, denitrification could be induced by providing the biofilm with external nitrate. This possibility was tested in a pilot-scale trickling filter by adding a pulse of nitrate to a highly loaded trickling filter. The experiment showed that denitrification can indeed be induced by adding nitrate at high loading conditions and that this way a considerably increased substrate removal capacity can be obtained. The fact that denitrification occurred was confirmed by the increased production of CO2 from bioconversion processes, without a major change of the O2 consumption. The simplified mixed-culture biofilm model developed by Rauch et al. was extended for the description of off-gas measurements and was able to describe the results of the experiment very well.
从液相转移到生物膜中的氧气可用于有机物的好氧降解和硝化作用。去除有机物的另一种可能途径是在生物膜更深层的缺氧区域进行反硝化作用。在高有机负荷率且生物膜氧气供应不足的情况下，通过向生物膜提供外部硝酸盐可诱导反硝化作用。在中试规模的滴滤池中通过向高负荷滴滤池添加硝酸盐脉冲来测试这种可能性。实验表明，在高负荷条件下添加硝酸盐确实可以诱导反硝化作用，并且通过这种方式可以获得显著提高的底物去除能力。生物转化过程中二氧化碳产量的增加证实了反硝化作用的发生，而氧气消耗量没有重大变化。劳赫等人开发的简化混合培养生物膜模型被扩展用于描述废气测量，并且能够很好地描述实验结果。
