3种单一及其混合碳源的生物反硝化脱氮效能

Biological Denitrification Efficiency of Three Single and Mixed Carbon Sources

分别以乙酸钠、乙醇、葡萄糖及其两两混合物作为外碳源,对生活废水进行生物反硝化研究。结果表明,不同碳源系统均出现了NO2^--N的短时间积累,与单一碳源系统相比,对应混合碳源系统NO2^--N最大积累量较低。从培养初始至120 min时,随培养时间增加,单一和混合碳源系统中NO3^--N含量均大幅降低,乙酸钠、乙醇、葡萄糖、乙酸钠+乙醇、乙醇+葡萄糖、乙酸钠+葡萄糖系统的平均反硝化速率分别为6.9、5.1、4.3、7.2、5.7、6.0 mg/(g·h),至120 min时,各系统NO3^--N去除率分别为100%、77.8%、64.8%、100%、78.4%、85.1%。乙酸钠、乙酸钠+乙醇、乙酸钠+葡萄糖系统NO3^--N去除率分别在120、120、210 min时达到100%。从脱氮效果、碳源成本、环境风险角度,乙酸钠+.葡萄糖更适合作为工程应用上的外碳源。

The biological denitrification of wastewater was studied by using sodium acetate,ethanol,glucose and their mixture as external carbon sources.The results showed that the short-term accumulation of NO2^--N has appeared in different carbon source systems.Compared with the single carbon source system,the maximum accumulation of NO2^--N in the corresponding mixed carbon source system were lower.From the initial culture to 120 min,with the increase of culture time,the content of NO3^--N in single and mixed carbon source systems decreased significantly.The average denitrification rates of sodium acetate,ethanol,glucose,sodium acctate+ethanol,ethanol+glucose,sodium acetate+glucose systems were 6.9,5.1,4.3,7.2,5.7,6.0 mg/(g·h)respectively.By 120 min,the removal rates of NO3^--N by each system were 100%,77.8%,64.8%,100%,78.4%and 85.1%,respectively.The removal rate of NO3^--N in sodium acetate,sodium acetate+ethanol,sodium acetate+glucose system reached 100%at 120,120,210 min respectively.From the perspective of denitrification effect,carbon source cost,environmental risk,sodium acetate+glucose is more suitable as an additional carbon source for engineering applications.