摘要
以高氨氮低碳氮比(C/N)的高级厌氧消化沼液为研究对象,采用序批式活性污泥法(SBR)反应器研究32℃、分步进水间歇曝气方式下中试规模的沼液的短程脱氮性能研究。结果表明:进水C/N的比值对脱氮性能影响很大,当进水C/N为1.6(沼液可生化降解特性B/C比为0.2)时,反应器内亚硝态氮浓度持续积累到高达950 mg·L^(-1),对TN和SCOD的去除率仅分别为15%和17%;当投加乙酸钠作为补充碳源至进水C/N提高到3.1后,亚硝态氮积累浓度迅速降低至20 mg·L^(-1)以下,TN和SCOD的去除率分别上升至95%和21%。逐步缩短HRT以提高运行负荷,发现氨氮负荷是系统稳定脱氮的制约因素,体系氨氮负荷最大为0.45 kg·(m^(3)·d)^(-1),当超该值后,TN的去除率将显著下降至80%左右,而对SCOD去除率影响不大。整个运行阶段反应器内亚硝态氮积累率达79.7%~96.7%,运行稳定期实现TN去除率达95%以上,系统在不需要额外添加碱度药剂的条件下实现了高效稳定的短程硝化反硝化。
Taking the advanced anaerobic digested biogas slurry with high ammonia nitrogen and low carbon nitrogen ratio(C/N)as the research object,stability of the short-cut nitrification of the biogas slurry on the pilot scale under 32℃,step-feeding and intermittent aeration mode was studied by using SBR reactor.The results show that the ratio of influent C/N has a great influence on the denitrification performance.When the influent C/N is 1.6(the biogas slurry B/C ratio is 0.2),the concentration of nitrous nitrogen in the reactor continues to accumulate to as high as 950 mg·L^(-1),the removal rates of TN and SCOD were only 15%and 17%,respectively.By contrast,as the influent C/N increased to 3.1 with added sodium acetate as a supplementary carbon source,the accumulated concentration of nitrite nitrogen rapidly decreased to below 20 mg·L^(-1),the removal rates of TN and SCOD increased to 95%and 21%,respectively.Gradually shortened hydraulic retention time(HRT)reveales that the ammonia load is a restricting factor for nitrogen removal.The maximum ammonia nitrogen load of the system was 0.45 kg·(m^(3)·d)^(-1),and when it exceeded this value,the removal rate of TN decreased significantly to 80%,but it has little effect on SCOD removal rate.The nitrite nitrogen accumulation rate in the reactor reaches 79.7%~96.7%in the whole operation stage,and the TN removal rate in the stable operation period reaches more than 95%.With efficient and stable short-cut nitrification-denitrification in a low C/N,moreover,and unnecessary for addition of alkaline,SBR shows great advantage for treating wastewater with high concentration of ammonia while low C/N ratio.
作者
刘勇
Liu Yong(Shanghai Tongji Environmental Engineering Technology Co.,Ltd.,Operation Department,Shanghai 200092,China)
出处
《广东化工》
CAS
2023年第8期168-170,共3页
Guangdong Chemical Industry
关键词
高级厌氧消化
沼液
高氨氮
低碳氮比
短程硝化反硝化
advanced anaerobic digestion
biogas slurry
high ammonia nitrogen
low C/N
short-cut nitrification and denitrification
