DO和曝停比对单级自养脱氮工艺影响试验研究

为提高SBBR单级自养脱氮系统脱氮性能并考察DO和曝/停比对SBBR单级自养脱氮系统的影响,采用4组对比试验进行研究.结果表明,连续和间歇2种曝气方式均可实现单级自养脱氮,在进水氨氮浓度为160 mg/L左右,温度30℃±2℃,pH值7.8～8.2,HRT为2 d,DO为0.8～1.0 mg/L的条件下,连续曝气系统的氨氮转化率和总氮去除率分别达到80%和70%.DO为(曝气)2.0～2.5　mg·L^-1/(停曝)0.2～0.4 mg·L^-1,曝/停比为2 h∶2 h的系统则达到90%和80%以上.SBBR单级自养脱氮系统的DO应随其曝/停比进行调节,同时还可能与反应器内生物量及微生物在活性污泥和生物膜中的分布情况有关.本研究还探讨了SBBR单级自养脱氮的机理.

Influence of DO and Aeration/Non-aeration Ratio on One-step SBBR Completely Autotrophic Nitrogen Removal Process

To improve the performance of single SBBR completely autotrophic nitrogen removal system and study the influence of aeration/non-aeration ratio on it, four reactors were applied in the experiment. The results showed that both continuous and intermittent aeration system could implement completely autotrophic nitrogen removal. On the conditions of ammonium concentration round 160 mg/L, temperature 30 degrees C +/- 2 degrees C, pH value 7.8-8.2, HRT 2 days and DO 0.8-1.0 mg/L, ammonium and total nitrogen removal efficiency reached 80% and 70% respectively in the continuous aeration system, and in the system of DO 2.0-2.5 (aeration) mg x L(-1)/ 0.2-0.4 (non-aeration) mg x L(-1), aeration/non-aeration ratio 2 h:2 h, ammonium and total nitrogen removal efficiency reached above 90% and 80% respectively. DO should be adjusted in accordance with aerobic/anaerobic ratio, and may be related to the biomass and its distribution between activated sludge and biofilm. The mechanism of nitrogen removal was also discussed.