单级序批式生物膜反应器(SBBR)多途径生物脱氮研究

Approaches of Biological Nitrogen Removal in a Single Sequencing Batch Biofilm Reactor

利用传统微生物分析技术与PCR、变性梯度凝胶电泳(DGGE)等分子生物学技术相结合的方法,对单级SBBR反应器中的主要生物脱氮途径进行分析.结果表明,亚硝化-厌氧氨氧化-反硝化途径是主要的脱氮途径,通过该途径去除的NH4+-N占总去除量的65%以上;另外2条途径则分别是亚硝化-反硝化途径以及全程硝化-反硝化途径.所有途径都采取同步和分步2种方式完成,同步方式以曝气阶段的氮素亏损形式予以表现.分步方式则依靠各种脱氮微生物在曝气阶段和厌氧阶段不同的活性程度完成,亚硝酸细菌是曝气阶段的主要活性菌种,完成NH4+-N向NO2--N的转化,而厌氧氨氧化细菌和反硝化细菌则在厌氧阶段成为优势菌种,完成完整的生物脱氮过程.

The conventional microorganism techniques and the molecule biological techniques such as PCR and DGGE were utilized to study the approaches of biological nitrogen removal in a single sequencing batch biofilm reactor （SBBR）. The main approach of biological nitrogen removal, no less than 65% of the total NH4^＋-N was removed in this approach, was composed of partial nitrification, anaerobic ammonium oxidation and denitrification.The second approach included twain processes such as partial nitrification and denitrification, and the third one was conventional nitrogen removal process （ nitrification and denitrification）. All approaches accomplished simultaneously or asynchronously. When the approach occurred in the simultaneous way, it performed as nitrogen-loss. The accomplisher of asynchronous way depended on the microbe＇s different activity between aerated phase and anaerobic phase. First, ammonia was converted to nitrite in the aerated phase when the nitrite bacteria performed high activity, and then anaerobic phase was operated in turn when the denitrifying bacteria and the anammox bacteria eliminated the nitrogen form gases.