亚硝氮对厌氧氨氧化EGSB反应器启动的影响

Effect of nitrite on start-up of anammox EGSB reactor

探究了进水亚硝氮质量浓度对厌氧氨氧化膨胀颗粒污泥床(EGSB)反应器启动的影响.接种4℃下长期储存的厌氧氨氧化污泥,结果发现:反应器R1(亚硝氮质量浓度为50.0 mg/L)的迟滞时间比R2(亚硝氮质量浓度为70.0 mg/L)少18 d,较高质量浓度亚硝氮对厌氧氨氧化反应器的启动有抑制作用.反应器R1和R2分别在第53天和第56天启动成功,总氮(TN)去除率分别达到67.9%和68.8%.提升氮负荷后,反应器R1和R2的氨氮去除率分别从93.1%和88.0%提高到99.6%和99.0%.通过水力冲击实验发现外循环可以增强反应器内基质混合效果,提高出水水质,反应器R1、R2分别在失稳后的第5天和第6天恢复.通过高通量测序发现2个反应器的优势菌属是Candidatus_Jettenia,相对丰度分别为54.1%和45.3%.长期储存的厌氧氨氧化污泥启动时亚硝氮质量浓度建议在50.0 mg/L以下.

Long-term stored anaerobic ammonia oxidation sludge at 4℃was inoculated to investigate the effect of influent nitrite on Anammox expanded granular sludge bed(EGSB)reactor start-up at 50.0 mg/L(R1)and 70.0 mg/L(R2).It was found that the retardation time of R1 was 18 days shorter than that of R2,and higher concentrations of nitrite(70.0 mg/L)inhibited the start-up of the Anammox EGSB reactor.R1 and R2 were successfully started at 53 d and 56 d,with total nitrogen(TN)removal rates of 67.9%and 68.8%,respectively.After increasing the nitrogen load,the ammonia removal rates of R1 and R2 increased from 93.1%and 88.0%,respectively,to 99.6%and 99.0%.The hydraulic shock experiment discovered that external circulation could enhance the substrate mixing effect in the reactor and improve the effluent water quality,and R1 and R2 recovered on the 5th and 6th days following destabilization,respectively.High-throughput sequencing revealed that the dominant genus in both reactors was C andidatus_Jettenia with a relative abundance of 54.1%and 45.3%,respectively.Long-term stored Anammox sludge was initiated with a nitrite concentration recommended below 50.0 mg/L.