Shizuoka Prefectural Research Institute of Animal Industry, Swine & Poultry Research Center, 2780 Nishikata, Kikugawa, Shizuoka, 439-0037, Japan.
National Agriculture and Food Research Organization (NARO), Institute of Livestock and Grassland Science, Animal Waste Management and Environment Research Division, 2 Ikenodai, Tsukuba, Ibaraki, 305-0901, Japan.
Chemosphere. 2021 Nov;282:131027. doi: 10.1016/j.chemosphere.2021.131027. Epub 2021 May 28.
In the anammox process, maintaining a high anammox activity at low water temperatures for stable nitrogen removal is a challenge. In this study, to verify the adaptability of anammox to low water temperatures, we investigated effects of annual temperature fluctuations on nitrogen removal in a full-scale swine wastewater treatment plant, where anammox bacteria accumulated. Annual quarters were defined as L-1 (November-January), L-2 (February-April), H-1 (April-July), and H-2 (July-October). The total nitrogen removal rate was stable at 0.08-0.11 kg-N/m/d, even during temperature fluctuations. Removal efficiencies of biochemical oxygen demand and total nitrogen were consistently high at 95-99% and 69-81%, respectively. The anammox activity and abundance of anammox bacteria were highest in granule L-1 and lowest in granule H-2. The optimal temperature for anammox activity shifted from 35 °C in granules H-1 and H-2 to 30 °C in granules L-1 and L-2, while the latter maintained a moderate activity compared to the former at low temperature. Candidatus Jettenia asiatica was predominant, especially in granule L-2, accounting for up to 54% of the microbial community composition at the genus level. The high specific anammox activity in granule L-2 was considered to be due to the abundance of anammox bacteria and the adaptation of Ca. Jettenia asiatica to low temperature. The anammox granules adapted well to low temperatures and demonstrated high efficiency in the simultaneous partial nitrification anammox and denitrification process without heating. Thus, constructing an energy-saving and cost-effective nitrogen removal system can be considered.
在厌氧氨氧化过程中，维持低温下的高厌氧氨氧化活性以实现稳定的氮去除是一项挑战。在本研究中，为了验证厌氧氨氧化对低温的适应性，我们调查了年温度波动对积累厌氧氨氧化菌的全规模猪场废水处理厂中氮去除的影响。将全年分为四个季度，分别为 L-1（11 月至 1 月）、L-2（2 月至 4 月）、H-1（4 月至 7 月）和 H-2（7 月至 10 月）。尽管温度波动，总氮去除率仍稳定在 0.08-0.11kg-N/m/d。生化需氧量和总氮的去除效率始终保持在 95-99%和 69-81%的较高水平。在颗粒体中，厌氧氨氧化活性和厌氧氨氧化菌的丰度在 L-1 最高，在 H-2 最低。厌氧氨氧化活性的最佳温度从 H-1 和 H-2 中的 35°C 转移到 L-1 和 L-2 中的 30°C，而后者在低温下与前者相比保持了中等活性。Candidatus Jettenia asiatica 占主导地位，特别是在 L-2 颗粒体中，占微生物群落组成的属级水平高达 54%。L-2 颗粒体中高比厌氧氨氧化活性被认为是由于厌氧氨氧化菌的丰度以及 Ca. Jettenia asiatica 对低温的适应。厌氧氨氧化颗粒体很好地适应了低温，在无需加热的情况下高效地进行部分硝化厌氧氨氧化和反硝化过程。因此，可以考虑构建节能且具有成本效益的氮去除系统。
