[Advances in heterotrophic nitrification-aerobic denitrifying bacteria for nitrogen removal under extreme conditions].

Heterotrophic nitrification-aerobic denitrification (HN-AD) is an enrichment and breakthrough theory of traditional autotrophic nitrification heterotrophic denitrification. Heterotrophic nitrification-aerobic denitrifiers with the feature of wide distribution, strong adaptability and unique metabolic mechanism have many special advantages, including fast-growing, rapid biodegradability and long lasting activity, which can rapidly remove ammonia nitrogen, nitrate nitrogen (NO₃⁻-N) and nitrite nitrogen (NO₂⁻-N) under aerobic conditions simultaneously. Therefore, HN-AD bacteria show the important potential for denitrification under extreme conditions with high-salt, low-temperature or high-ammonia nitrogen environment, and HN-AD bacteria attract extensive attention in the field of biological denitrification of wastewater. In this review, we first introduce the previously reported HN-AD bacterial species which have denitrification performance in the extreme environments and state their typical metabolic mechanism. Then, we systematically analyze the nitrogen removal characteristics and potential under extreme conditions. We also briefly describe the progress in the application of HN-AD bacterial. Finally, we outlook the application prospects and research directions of HN-AD denitrification technology.异养硝化-好氧反硝化 (HN-AD) 是对传统自养硝化异养反硝化理论的丰富与突破。HN-AD 菌在好氧条 件下可快速实现氨氮、硝态氮 (NO₃⁻-N)、亚硝态氮 (NO₂⁻-N) 三氮同步脱除。它们不仅具有分布范围广、适应能力强、代谢通路特殊等特点，而且还具有世代时间短、脱氮速率快、高活性持久等独特优势，在高盐、低温、高氨氮等极端条件表现出了巨大的脱氮潜力，因此在废水生物脱氮领域受到广泛关注。文中在介绍HN-AD 菌属类别及代谢机理的基础上，重点总结了在高盐、低温、高氨氮等极端条件下进行氨氮脱除的HN-AD 种属，系统分析了它们在极端条件下的脱氮特性及潜力，并简述了HN-AD 菌在极端条件下的工艺应用研究进展，最后展望了HN-AD 脱氮技术的应用前景和研究方向。.