Lopez C, Pons M N, Morgenroth E
Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, 3219 Newmark Civil Engineering Laboratory, 205 North Mathews Avenue, Urbana, IL 61801, USA.
Water Res. 2006 May;40(8):1519-30. doi: 10.1016/j.watres.2006.01.040.
In many biological wastewater treatment systems, bacterial growth and the amount of active biomass are limited by the availability of substrate. Under these low growth conditions, endogenous processes have a significant influence on the amount of active biomass and therefore, the overall system performance. In enhanced biological phosphorus removal (EBPR) systems endogenous processes can also influence the levels of the internal storage compounds of the polyphosphate accumulating organisms (PAO), directly affecting phosphorus removal performance. The purpose of this study was to evaluate the significance of different endogenous processes that occur during the long-term starvation of EBPR sludge under aerobic and anaerobic conditions. Activated sludge obtained from a laboratory sequencing batch reactor was used to perform a series of batch starvation experiments. Under aerobic starvation conditions we observed a significant decay of PAO (first-order decay rate of 0.15/d) together with a rapid utilization of polyhydroxyalkanoates (PHA) and a slower utilization of glycogen and polyphosphate to generate maintenance energy. On the other hand, anaerobic starvation was best described by maintenance processes that rapidly reduce the levels of polyphosphate and glycogen under starvation conditions while no significant decay of PAO was observed. The endogenous utilization of glycogen for maintenance purposes is currently not included in available EBPR models. Our experimental results suggest that mathematical models for in EBPR should differentiate between aerobic and anaerobic endogenous processes, as they influence active biomass and storage products differently.
在许多生物废水处理系统中，细菌生长和活性生物量的数量受到底物可用性的限制。在这些低生长条件下，内源过程对活性生物量的数量有重大影响，因此也对整个系统性能有重大影响。在强化生物除磷（EBPR）系统中，内源过程也会影响聚磷积累生物体（PAO）的内部储存化合物水平，直接影响除磷性能。本研究的目的是评估在好氧和厌氧条件下EBPR污泥长期饥饿期间发生的不同内源过程的重要性。从实验室序批式反应器获得的活性污泥用于进行一系列批次饥饿实验。在好氧饥饿条件下，我们观察到PAO显著衰减（一级衰减率为0.15/d），同时聚羟基脂肪酸酯（PHA）迅速被利用，糖原和聚磷酸盐的利用较慢，以产生维持能量。另一方面，厌氧饥饿最好用维持过程来描述，即在饥饿条件下聚磷酸盐和糖原水平迅速降低，而未观察到PAO显著衰减。目前可用的EBPR模型未包括用于维持目的的糖原内源利用。我们的实验结果表明，EBPR的数学模型应区分好氧和厌氧内源过程，因为它们对活性生物量和储存产物的影响不同。
