好氧亚硝化颗粒污泥特性的研究

Characteristics of Aerobic Short-cut Nitrification Granular Sludge

对在小试曝气上流式污泥床反应器中成功培养出的好氧亚硝化颗粒污泥的特性进行了研究.工艺稳定运行时,亚硝化颗粒污泥的VSS/SS稳定在80%左右,粒径大于1.0 mm的颗粒污泥约占总数的70%,粒径大于0.8 mm的颗粒污泥的湿密度约为1 022 kg/m3.荧光原位杂交结果表明,亚硝化细菌主要分布在颗粒污泥的表层,而硝化细菌则分布在表层之下;最大可能数结果显示,亚硝化工艺稳定运行时亚硝化细菌的数量远多于硝化细菌,甚至可高于硝化细菌4个数量级以上.上述结果表明,硝化细菌(AOB和NOB)以接种的产甲烷颗粒污泥或其碎片为载体,通过在其表层附着生长,最终形成好氧亚硝化颗粒污泥.

The physical properties and microbiological characteristics of aerobic short-cut granular sludge, which was cultivated in a lab-scale aerated upflow sludge bed （AUSB） reactor, were investigated. When the short-cut nitrification process was performed stably, the ratios of VSS/ SS of short-cut granules were kept at about 80% , the amount of granules with diameter larger than 1.0 mm was about 70% of the total, and the wet density of granules with diameter larger than 0.8mm was about 1 022 kg/m^3. The fluorescence in situ hybridization （FISH） results indicated the ammonia oxidation bacteria （AOB） were mainly located in the surface layer of the granules, and the nitrite oxidation bacteria （NOB） were in the inner layer. The results of most probable number （MPN） showed that, as the short-cut process was operated stably, the amount of AOB was much more than that of NOB, and sometimes the AOB amount was even 10 thousands times more than that of NOB. All these results indicated that, using the seed granules or their debris as the support media, AOB and NOB were attached and grown on the surface of the media, and finally the aerobic short-cut nitrification granules were formed.