Barnard James L, Dunlap Patrick, Steichen Mark
Water Environ Res. 2017 Nov 1;89(11):2043-2054. doi: 10.2175/106143017X15051465919010.
Enhanced biological phosphorus removal (EBPR) was observed in high-rate, non-nitrifying plants in the United States that were operated in a plug-flow mode. In facilities designed for nitrification and denitrification, a first-stage anaerobic zone, free of nitrate and nitrite was needed to accomplish EBPR, and this is referred to as the Phoredox (a.k.a. the AO and A2O) process. When a biological mechanism responsible for EBPR was proposed, these treatment configurations were accepted as normal practice, but many later observations showed that more reliable phosphorus removal could be achieved with alternative configurations. This paper discusses the development of alternative configurations for EBPR and the likelihood that a host of phosphate accumulating organisms (PAOs) that react to different environmental conditions might play a much bigger role in reliable and sustainable biological phosphorus removal. The conclusion is that conventional designs might have inadvertently selected for less efficient PAOs, while alternative configurations allowed for the growth of multiple PAO species such as Tetrasphaera, which can ferment higher carbon forms and take up phosphorus under anoxic conditions.
在美国以推流模式运行的高速、非硝化处理厂中观察到了强化生物除磷（EBPR）现象。在设计用于硝化和反硝化的设施中，需要一个不含硝酸盐和亚硝酸盐的第一阶段厌氧区来实现EBPR，这被称为Phoredox工艺（又称AO和A2O工艺）。当提出负责EBPR的生物学机制时，这些处理工艺配置被视为常规做法，但后来的许多观察表明，采用替代配置可以实现更可靠的除磷效果。本文讨论了EBPR替代配置的发展，以及众多对不同环境条件有反应的聚磷菌（PAO）在可靠和可持续生物除磷中可能发挥更大作用的可能性。结论是，传统设计可能无意中选择了效率较低的PAO，而替代配置则允许多种PAO物种生长，如Tetrasphaera，它可以发酵更高碳形式的物质并在缺氧条件下吸收磷。
