Institute for Water Quality and Resource Management, TU Wien, Karlsplatz 13/226-1, 1040, Vienna, Austria.
Institute for Water Quality and Resource Management, TU Wien, Karlsplatz 13/226-1, 1040, Vienna, Austria.
J Environ Manage. 2019 Feb 1;231:953-961. doi: 10.1016/j.jenvman.2018.10.101. Epub 2018 Nov 11.
Up to now, aerobic granulation of activated sludge is only realised in SBRs, where the discontinuous feed and sedimentation allow the formation of dense granules with excellent settling properties. However, aerobic granulation in continuous-flow plants (CFP) is gaining more and more interest in order to exploit the advantages of these excellent sludge properties to construct compact and efficient WWTP. Within the scope of this project, a SBR and CFP were operated in parallel to investigate the aerobic granulation of activated sludge and to compare the biomass in terms of their structure and settling behavior. CFP operation included two experimental phases with different reactor designs. The use of synthetic wastewater during phase I led to a biomass with a SVI of 42 ml g, whereby the SVI declined only to 85 ml g in the second phase and the use of municipal sewage. After the start-up period, microscopic images of the biomass from CFP comprised small compact granules with a high flocculent fraction. Particle size distribution for phase II confirm, that 72% of the particles had a size over 200 μm. A strong correlation was observed between the appearance of NO-N in the first reactor and the SVI. The results illustrate, that the anaerobic conditions during feeding are essential to keep stable granules.
到目前为止，活性污泥的好氧颗粒化仅在 SBR 中实现，其中不连续的进料和沉淀允许形成具有优异沉淀性能的密集颗粒。然而，为了利用这些优异的污泥特性来构建紧凑高效的 WWTP，连续流工厂（CFP）中的好氧颗粒化越来越受到关注。在该项目的范围内，SBR 和 CFP 并行运行，以研究活性污泥的好氧颗粒化，并比较其结构和沉淀行为方面的生物量。CFP 操作包括两个具有不同反应器设计的实验阶段。在第一阶段使用合成废水导致生物量的 SVI 为 42 ml/g，而在第二阶段使用城市污水时，SVI 仅下降到 85 ml/g。启动阶段后，CFP 生物量的微观图像由具有高絮凝分数的小型紧凑颗粒组成。第二阶段的颗粒尺寸分布证实，72%的颗粒粒径大于 200 μm。在第一个反应器中出现 NO-N 与 SVI 之间存在很强的相关性。结果表明，进料过程中的厌氧条件对于保持稳定的颗粒至关重要。
