低曝气量与实时控制下的常温短程硝化研究

Shortcut Nitrification at Ambient Temperature with Low Aeration Rate and Real-time Control

为了使短程硝化反硝化技术应用于工程,采用SBR法处理实际的生活污水,考察了曝气量对亚硝酸氮积累的影响,以及实现短程硝化后,通过在线监测DO、pH实时控制曝气时间并逐渐提高曝气量,维持短程硝化的效果。结果表明,23℃下,当固定曝气时间为10 h、曝气量为40L/h时,DO平均为2 mg/L,未出现亚硝酸氮积累;当曝气量为32 L/h时DO平均为0.5 mg/L,亚硝化率(NO-2/NOx-)平均达到了34%;当曝气量为28 L/h时DO平均为0.3 mg/L,亚硝化率可达80%以上,实现了短程硝化。此后逐渐提高曝气量至40、48、56 L/h,同时通过在线监测DO、pH实时控制曝气时间,不仅未破坏短程硝化,而且使硝化时间不断缩短,同时亚硝酸氮的积累率稳定维持在95%左右。

The effect of the aeration rate on nitrite nitrogen accumulation in SBR fed with domestic wastewater was studied. The maintenance of shortcut nitrification by real-time control was also investigated. The results indicate that under the conditions of temperature of 23 ℃ and aeration time of 10 hours, the nitrite nitrogen accumulation rates （ NO2^-/NOx^- ） are 0%, 34% and 80%, respectively when the aeration rates are 40 L/h, 32 L/h and 28 L/h, and the average DO is 2 mg/L, 0.5 mg/L and 0.3 mg/L, respectively. The aeration rates are gradually increased to 40 L/h, 48 L/h and 56 L/h, shortcut nitrification time is reduced and the nitrite nitrogen accumulation rate is stabilized around 95% by on-line monitoring DO and pH.