不同碳源对反硝化SBR反应器N2O释放的影响

试验使用SBR反应器，采用乙酸钠、乙醇、葡萄糖和蔗糖4种常用的外加有机碳源，对反硝化反应中N₂O释放过程进行研究。结果表明:4种碳源条件下，N₂O积累量均呈先升高后降低最后保持稳定的趋势。N₂O最大积累量分别为1.59，1.25，5.43，0.66 mg/L，最大转化率分别为1.61%、1.36%、5.44%和0.67%；最终积累量分别为1.02，0.67，3.12，0.49 mg/L，最终转化率分别为1.04%、0.73%、3.13%和0.50%。N₂O释放量及转化率顺序均为葡萄糖>乙酸钠>乙醇>蔗糖。游离亚硝酸抑制、不同反硝化酶的电子竞争和微生物群落结构差异均是影响N₂O释放的因素。

EFFECT OF DIFFERENT CARBON SOURCES ON N2O RELEASE IN DENITRIFICATION PROCESS OF A SBR REACTOR

N₂O is a potent greenhouse gas, and releases a lot in wastewater treatment. Understanding the influencing factors of N₂O release in wastewater treatment can reduce N₂O emissions. Four classical external organic carbon sources, such as sodium acetate, ethanol, glucose and sucrose, were used to study the N₂O release process in denitrification process with SBR reactors. The results showed that under the 4 carbon source conditions, the accumulation of N₂O showed a trend of first increasing, then decreasing, and finally remaining stable. The maximum accumulation of N₂O were 1.59, 1.25, 5.43, 0.66 mg/L, and the maximum conversion rates were 1.61%, 1.36%, 5.44% and 0.67%, respectively. The final accumulation of N₂O were 1.02, 0.67, 3.12, 0.49 mg/L, and the final conversion rates were 1.04%, 0.73%, 3.13% and 0.50%, respectively. The N₂O release amount and conversion rate in descending order were glucose, sodium acetate, ethanol and sucrose. FNA inhibition, electronic competition of different denitrifying enzymes and differences in microbial community structure were factors affecting N₂O release.