曝气量对悬浮系统单级自养脱氮性能的影响

通过连续实验和间歇实验研究了不同曝气量对SBR系统自养脱氮性能的影响。连续实验表明,在进水氨氮浓度为155～185 mg/L时,曝气量分别为20、28、36和44 L/h时,TN去除率分别为80%、82%、80%和77%;增大和减小曝气量均会降低系统的脱氮效率。间歇实验表明,随着曝气量的增加,氨氮的降解速率有所升高,20、28、36和44 L/h曝气条件下氨氮的降解速率分别为7.23、7.25、7.86和7.95 mg/(g MLVSS.h);在降解的过程中DO浓度一直维持在较低的水平(<0.5 mg/L),pH值则呈先升高后降低的趋势;氨氮降解结束时,pH值和DO浓度同时升高。结果表明,改变曝气量会影响单级自养脱氮反应的进程,但对降解过程DO浓度值变化不大;DO浓度和pH值变化对氨降解结束具有指示作用。

Effect of aeration on single-stage autotrophic nitrogen removal in suspended system

Continuous and batch experiments were performed to investigate the effect of aeration on single-stage autotrophic nitrogen removal in a SBR. When the influent of ammonia concentration was in the range of 155~185 mg/L, 80%, 82%, 80% and 77% of TN removal efficiency was obtained under different aeration of 20, 28, 36 and 44 L/h, which showed that both a higher and a lower aeration decreased TN removal efficiency. Batch experiments showed that ammonia degradation rate increased with the increment of aeration. Ammonia degradation rates of 7.23, 7.25, 7.86 and 7.95 mg/(g MLVSS·h) were obtained under different aeration of 20, 28, 36 and 44 L/h. During degradation, DO maintained at a low concentration (<0.5 mg/L) and pH first increased and then returned. At the end of degradation, both DO and pH increased. As a result, the degradation rate increased with increment of aeration and variation of pH and DO could indicate the ending of the degradation.