通过试验模拟不同幅度、不同频率的脉冲式进水流量波动,研究脉冲式流量波动对已稳定运行的厌氧氨氧化UASB反应器性能的冲击影响.结果表明,在脉冲波动幅度小于60m L/min(上升流速1.33cm/min)范围内,厌氧氨氧化UASB反应器表现出良好的适应性和承受力,甚至对于高频率的波动冲击,出水也可达到一级A标准,NH_4~+-N和NO_2~--N去除率都基本维持在80%以上,总氮去除率维持在70%以上.而当脉冲的波动幅度为100m L/min(上升流速2.22cm/min)时,则UASB反应器的出水水质波动性大,随着波动频率的增大,反应器的适应时间增长,一直到波动频率为1.5h时,反应器出水NH_4~+-N和NO_2~--N浓度难以稳定在5mg/L以下.随着波动幅度由40m L/min增大到60,100m L/min,反应器内污泥中厌氧氨氧化菌的丰度值和厌氧氨氧化菌占全细菌的百分含量均呈现先增多后减少的趋势,在波动幅度为60m L/min时均为最大,可能是由于此时污泥和基质的混合与接触更为高效,氮去除效率高,更有利于厌氧氨氧化菌的生长.
Due to the fluctuation of upstream sewage during the actual operation, the effect of pulsed inflow shock on the stability of anaerobic ammonium oxidation (ANAMMOX) process was evaluated in the present study through changing the amplitude and frequency of pulsed inflow. The results showed that the ANAMMOX process in UASB reactor had a good adaptivity and tolerance towards pulsed inflow when the amplitude was less than 60mL/min(vup~o~=l.33cm/min). Even through the pulsed frequency came to a high level, the effluent could meet the national 1-A standard. The removal efficiency ratio of NH4+-N and NO2--N could both been kept above 80% and the removal ratio of total nitrogen was above 70%. The process of ANAMMOX in UASB reactor was unstable when the pulsed amplitude came to 100mL/min (Vupnow=2.22cm/min). With the enhancement of pulsed frequency, the adaptation time of ANAMMOX process increased. The concentrations of NH4+-N and NO2 -N in effluent were both above 5mg/L when the pulsed frequency came to 1.5h. Moreover, when the pulsed amplitude increased from 40mL/min to 60mL/min and 100mL/min, the abundance of anammox bacteria in reactor and the percentage of anammox on total bacteria firstly increased and then decreased. The abundance and percentage of anammox bacteria in total bacteria came to the highest level when the pulsed amplitude came to 60mL/min. The reason might be that the mixture and contaction of the anammox and the substance were more efficient, which facilited the growth of anammox bacteria.