好氧颗粒污泥工艺强化脱氮研究进展

Review on enhanced denitrification of aerobic granular sludge technology

好氧颗粒污泥是微生物通过自凝聚作用形成的一种特殊的生物聚集体,具有结构致密、沉降性能优异、抗冲击负荷能力强、多功能微生物分区定殖等特点,其在废水强化脱氮除磷与难降解有机物去除方面具有明显的技术优势.针对目前工业和养殖废水及城镇生活污水等碳氮比低、处理出水总氮达标压力大等突出问题,综述基于好氧颗粒污泥的全自养、同步硝化反硝化、短程硝化反硝化、短程硝化-厌氧氨氧化、异养硝化-好氧反硝化等强化脱氮工艺,介绍其脱氮机制及技术优势,阐明不同好氧颗粒污泥脱氮工艺的特点与颗粒污泥特性,同时总结各种工艺的启动条件及富集相应功能菌的好氧颗粒污泥的形成因素,评估不同工艺应用于实际废水生物处理的可行性.在此基础上进一步分析进水基质组成（不同碳氮比）、运行模式（连续曝气和间歇曝气）、运行条件（溶解氧浓度、温度和pH）等对好氧颗粒污泥工艺强化脱氮性能与稳定运行的影响.最后提出应进一步优化好氧颗粒污泥强化脱氮工艺的运行参数,解析好氧颗粒污泥微生物菌群功能,揭示好氧颗粒污泥形成与结构稳定的微生物学机理.

Aerobic granular sludge（AGS） is a kind of biological aggregate formed by microbial self-immobilization, with advantages of compact structure, excellent setting ability, strong resistance to influent loading rates, and diversity in microbial species. It also has other advantages, such as enhanced removal of nitrogen, phosphorus, and refractory organics. In view of（1） low mass concentration ratio between chemical oxygen demand（COD） and total nitrogen（TN） of industrial and aquaculture wastewater, and urban domestic wastewater and（2） strict standard for TN removal, the present review illustrates several denitrification processes in AGS, including completely autotrophic nitrification, simultaneous nitrification and denitrification, shortcut nitrification-denitrification, partial nitrification-anaerobic ammonia oxidation, and heterotrophic nitrification-aerobic denitrification. The nitrogen removal mechanism and technical advantages of AGS process have been expounded. In addition, the characteristics of denitrification processes based on AGS have also been presented. The start-up conditions of various processes and the formation factors of AGS enriched with corresponding functional bacteria have been summarized, and the feasibility of the application of different processes in biological treatment of wastewater has been evaluated. Furthermore, the inf luence factors, such as inf luent composition（different COD/TN ratio）, operational mode（continuous aeration and intermittent aeration）, and operating conditions（dissolved oxygen concentration, temperature, and pH） on enhanced nitrogen removal and stable operation of AGS process have been discussed, which provides guidance for optimization of nitrogen removal performance of AGS. We have also pointed the trend for further research, such as optimization of the operating parameters of AGS-enhanced nitrogen removal processes, analysis of microbial community function of AGS, microbiological mechanism of AGS formation, and structural stability.