Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China.
Bioresour Technol. 2012 Nov;123:312-7. doi: 10.1016/j.biortech.2012.07.003. Epub 2012 Jul 13.
Microscopic observation and settling test were carried out to investigate the structure, density and settlability of anammox granules taken from a high-rate upflow anaerobic sludge blanket (UASB) reactor. The results showed that the anammox granules were irregular in shape and uneven on surface, and their structure included granule, subunit, microbial cell cluster and single cell. The gas pockets were often observed in the anammox granules, and they originated from the obstruction of gas tunnel by extracellular polymer substances (EPSs) and the inflation of produced dinitrogen gas. The volume of gas pockets became larger with the increasing diameter of anammox granules, which led to the decreasing density and the floatation of anammox granules. The diameter of anammox granules should be controlled at less than 2.20mm to avoid the granule floatation. A hypothesized mechanism for the granulation and floatation of anammox biomass was proposed.
采用微观观察和沉淀实验对取自高效上流式厌氧污泥床（UASB）反应器的厌氧氨氧化颗粒的结构、密度和沉降性能进行了研究。结果表明，厌氧氨氧化颗粒形状不规则，表面凹凸不平，其结构包括颗粒、亚单位、微生物细胞簇和单细胞。在厌氧氨氧化颗粒中经常观察到气穴，它们是由胞外聚合物（EPS）阻塞气体通道和产生的氮气膨胀引起的。随着厌氧氨氧化颗粒直径的增大，气穴的体积增大，导致密度降低和厌氧氨氧化颗粒浮起。应控制厌氧氨氧化颗粒的直径小于 2.20mm，以避免颗粒浮起。提出了一种关于厌氧氨氧化生物量颗粒化和浮起的假设机制。
