耐低温生物脱氮机制与对策研究进展

State of the art for mechanisms and countermeasures of low temperature biological nitrogen removal

废水处理系统中不可避免存在着低温环境,低温使得硝化菌和反硝化菌的活性下降,如何在低温条件下提高污水生物脱氮效果是废水处理研究工作中亟待解决的问题。本文对近年来研究发现的低温微生物耐低温机制进行了梳理,提出了最近发现的胞外聚合物(EPS)和聚羟基脂肪酸酯(PHA)的作用机理;介绍了几种已被研究证实能在低温下进行脱氮的功能菌与一些可以提高低温污水脱氮效果的新技术/工艺(包括使用新型填料、改变碳源投加方式、投加特定的重金属);阐述了目前研究所遇到的一些问题,如缺乏工程实践、处理水质与研究菌株单一,研究结论与实际废水处理应用还有着差距。指出未来可以通过特异性功能菌的固定与使用、生物倍增技术与工程实践结合等方法来降低运行成本,提高低温污水的脱氮效果。

Low temperature environment is inevitably encountered in the wastewater treatment system operation. Low temperature decreases the activities of nitrifying bacteria and denitrifying bacteria. How to improve the biological nitrogen removal effect in the wastewater treatment system under low temperature is one of the urgent tasks in the wastewater treatment research. The mechanisms of cold adapted microorganism’s resistance to low temperature found in recent years are discussed in this paper. The function of extracellular polymeric substance(EPS) and polyhydroxyalkanoate(PHA) are proposed.Several functional bacteria which have been proved to be capable of denitrification at low temperature and some new technologies/processes which can improve the denitrification effect of low temperature wastewater are introduced(including the use of new fillers, change of carbon sources supplement pattern and add specific heavy metals). The problems encountered in the present research are described: lack of engineering application, treating water quality and strains are relatively simple. There is still a gap between the research conclusion and the actual application. The fixation and use of specific functional bacteria, Bio-Dopp and engineering application can be combined to reduce operating costs and improve the biological nitrogen removal effect of low temperature wastewater in the future.