采用序批式气升环流生物反应器(SBAR)构建短程同步硝化反硝化(SND)体系,在此基础上,考察碳源类型对短程SND脱氮特性与N2O释放的影响。研究发现,碳源类型可引起脱氮中间产物NO2-的积累率差异,从而导致N2O释放的显著不同。分别以葡萄糖、乙酸钠、可溶性淀粉为碳源的反应器,在短程SND脱氮过程中,NO2-积累率分别为88.35%、93.67%和70.39%;以乙酸钠为碳源时,N2O释放量及其转化率最高,其N2O释放量约为葡萄糖和可溶性淀粉的1.5倍,N2O转化率则比葡萄糖和可溶性淀粉高出约25%。污泥微观结构的SEM照片和SOUR结果表明,不同碳源所形成的好氧颗粒污泥中微生物组成与活性的差异,造成脱氮过程NO2-积累程度的不同,从而导致N2O释放特征的差异。
Short-cut simultaneous nitrification and denitrification (SND) was achieved in a sequencing batch airlift reactor (SBAR). Based on this condition, the effect of carbon source types on the nitrogen removal performance and N2O emission characteristic in the short-cut SND process was evaluated. The results showed that the carbon source had a great effect on nitrite accumulation rate (NAR), resuiting in the dramatic difference of N2O emission. The NARs of short-cut SND process, simulated by glucose, acetate and starch, were 88.35%, 93.67% and 70.39%, respectively. The N2O emission with acetate as carbon source was nearly 1.5 times as much as those with glucose and starch, and the N2O conversion rate with acetate as the carbon source was about 25% higher than those with glucose and starch. The results of the scanning electron micrograph of sludge microstructure and the specific oxygen uptake rate indicated that the differences of microbial composition and activity of aerobic granules formed by different carbon sources resulted in the different degrees of nitrite accumulation rate, which led to the variation of N2O emission in the short-cut SND process.