Munz Giulio, Gualtiero Mori, Salvadori Laura, Claudia Barberio, Claudio Lubello
Department of Civil and Environmental Engineering, University of Florence, 50139 Florence, Italy.
Bioresour Technol. 2008 Dec;99(18):8559-64. doi: 10.1016/j.biortech.2008.04.006. Epub 2008 May 21.
In this study a pilot-scale membrane bioreactor (MBR) and a conventional activated sludge plant (CASP), treating the same tannery wastewaters and in the same operating conditions, have been compared in order to evaluate the overall treatment efficiency, the presence and distribution of Gram negative bacteria and the kinetics of nitrifying bacteria. Process efficiency was evaluated in terms of organic and nitrogen compounds: the MBR showed a higher COD removal (+4%) and a more stable and complete nitrification. The Gram negative bacteria were detected by fluorescent in situ hybridization (FISH) with phylogenetic probes monitoring of alpha-, beta- and gamma-Proteobacteria, of the main ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria of the Nitrobacter and Nitrospira genera. The results showed that the main differences between the two sludges were: the higher abundance of alpha- and gamma-Proteobacteria in the MBR bioreactor and the presence of AOB aggregates only on the surfaces of MBR flocs. Finally, the titrimetric (pH-stat, DO-stat) tests showed similar values of the kinetic parameters of the nitrifiers both in MBR and CASP sludge.
在本研究中，对处理相同制革废水且运行条件相同的中试规模膜生物反应器（MBR）和传统活性污泥处理厂（CASP）进行了比较，以评估整体处理效率、革兰氏阴性菌的存在及分布情况以及硝化细菌的动力学。从有机和氮化合物方面评估了处理工艺效率：MBR表现出更高的化学需氧量（COD）去除率（提高了4%）以及更稳定、更完全的硝化作用。通过荧光原位杂交（FISH），使用系统发育探针监测α-、β-和γ-变形菌纲、主要的氨氧化细菌（AOB）以及硝化杆菌属和硝化螺菌属的亚硝酸盐氧化细菌，来检测革兰氏阴性菌。结果表明，两种污泥之间的主要差异在于：MBR生物反应器中α-和γ-变形菌纲的丰度更高，且AOB聚集体仅存在于MBR絮体表面。最后，滴定法（pH稳态、溶解氧稳态）测试表明，MBR和CASP污泥中硝化菌的动力学参数值相似。
