耐低温异养硝化-好氧反硝化菌N2的脱氮性能与应用
Nitrogen Removal Performance and Application of Low-temperature Tolerant Heterotrophic Nitrification-Aerobic Denitrification Bacteria N2
张婷 1刘诗园 1高雅娟 1胡凌康 1李晨晨 1谭骞骞 1张国伟 1靳永胜1
作者信息
- 1. 北京农学院生物与资源环境学院/植物科学技术学院,北京 102206
- 折叠
摘要
低温会抑制脱氮菌的生长与代谢,从而导致冬季污水处理厂存在脱氮效果差、出水水质难以达标的问题,筛选在低温条件下具有高效脱氮能力的异养硝化-好氧反硝化菌株是解决该问题的关键措施.本研究从内蒙古某化工厂的活性污泥中筛选分离耐低温脱氮菌株,并对菌株进行鉴定;分别以氨氮、硝态氮及亚硝态氮为唯一氮源研究其脱氮特性,进一步分析不同单因素条件—碳源、碳氮比(C/N)、pH、转速和温度对菌株脱氮性能的影响,通过响应面法优化菌株脱氮效率的关键因子,确定菌株最佳脱氮条件;最后,将分离的菌株用于2种不同类型的污水,检测其脱氮效果.结果显示,从污泥中筛出的耐低温菌经鉴定属于阴沟肠杆菌(Enterobacter cloacae),命名为N2(GenBank No.OQ834747);菌株N2在8℃条件下对氨氮(304 mg/L)、硝态氮(37 mg/L)、亚硝态氮(30 mg/L)的去除率均达到100%.在碳源为蔗糖、C/N为8～20、pH 7～9、转速150～180 r/min时,对300 mg/L氨氮表现出优异的去除能力,其中最优脱氮条件为:碳源为蔗糖,C/N为8.97,pH 6.62,在此条件下总氮的去除率最高(83.2%);菌株N2在8℃低温条件下,对化工厂污水和焦化厂污水的氨氮去除率分别达到100%和91%,总氮去除率分别达到99%和80%.因此,菌株N2在低温条件下具有优异的生长和脱氮性能,可应用于寒冷地区的污水脱氮.
Abstract
Low temperature will inhibit the growth and metabolism of denitrifying bacteria,resulting in poor nitrogen removal efficiency and substandard effluent quality in winter sewage treatment plants.The key measure to solve the problem is to screen the heterotrophic nitrifying and aerobic denitrification strains with high denitrification ability at low temperature.In this study,the low-temperature denitrifier strain was isolated from the activated sludge of a chemical plant in Inner Mongolia,and the strains was identified.Nitrogen removal characteristics were studied by using ammonia nitrogen,nitrate nitrogen and nitrite nitrogen as the only nitrogen sources.The effects of different single factors(carbon source,C/N,pH,rotational speed,temperature)on nitrogen removal performance were studied.The response surface method was used to optimize the key factors of nitrogen removal efficiency in order to determine the optimal nitrogen removal conditions.Finally,the isolated strain was applied to 2 different types of sewage in order to test its nitrogen removal effect.The results showed that the low-temperature resistant bacteria screened from sludge were identified as Enterobacter cloacae,and named N2(GenBank No.OQ834747).The removal efficiency of strain N2 on ammonia nitrogen(304 mg/L),nitrate nitrogen(37 mg/L)and nitrite nitrogen(30 mg/L)reached 100%at 8℃.The strain N2 showed excellent removal ability of 300 mg/L ammonia nitrogen when carbon source of sucrose,carbon-to-nitrogen ratio(C/N)of 8～20,pH of 7～9,and rotation speed of 150～180 r/min,the optimal nitrogen removal conditions of strain N2 were as follows:carbon source of sucrose,C/N of 8.97,pH of 6.62,under these conditions,the removal rate of total nitrogen reached the highest(83.2%).Under the condition of low temperature of 8℃,the ammonia nitrogen removal rate of chemical plant sewage and coking plant sewage reached 100%and 91%,and the total nitrogen removal rate reached 99%and 80%,respectively.Therefore,N2 strain has excellent growth and nitrogen removal performance at low temperature and could be applied to wastewater nitrogen removal in cold areas.
关键词
低温/异养硝化-好氧反硝化菌/脱氮/污水处理Key words
Low temperature/Heterotrophic nitrification-Aerobic denitrifying bacteria/Denitrification/Sewage treatment引用本文复制引用
基金项目
北京农学院学位与研究生教育改革与发展项目(5076516020/018)
出版年
2024
国家科技期刊平台
NSTL
万方数据