调整气水比优化高氨氮废水BAF一体化脱氮

为实现常温下高氨氮废水中氮的高效去除，选取8：1、12：1和15：1等3个气水比（GWR）条件，考察常温下曝气生物滤池（BAF）短程硝化-厌氧氨氧化（ANAMMOX）一体化自养脱氮工艺稳定运行的性能.研究结果表明：进水氨氮（NH₄⁺-N）浓度为400mg/L、回流比为1：1的条件下，GWR为15：1脱氮效果最好，氨氮去除率（ARE）达90%以上，总氮（TN）去除负荷为1.1kgN/（m³·d），去除率达83%.GWR为15：1时，溶解氧（DO）为2.41~4.22mg/L，进水NH₄⁺-N转化为亚硝（NO₂^--N）量增加，ANAMMOX活性增强.对生物膜进行功能菌种实时荧光定量PCR（qPCR）分析得出，GWR为15：1时，ANAMMOX和氨氧化菌（AOB）两者丰度均最高，高达10¹² copies/g dry sludge以上，一体化脱氮效果最好.同时，研究表明提高GWR后ANAMMOX反应增强，而过程中无N₂O生成，GWR为15：1时，N₂O总释放量最小，释放因子为0.0012.

Optimization of the integrated nitrogen removal process of high ammonia nitrogen wastewater in BAF by adjusting the gas water ratio

In order to achieve efficient removal of nitrogen from high ammonia nitrogen wastewater at room temperature, this study selected three gas water ratio conditions, 8:1、12:1 and 15:1 respectively. It investigated the stable operation performance of partial nitrification-ANAMMOX integrated autotrophic nitrogen removal process of biological aerated filter (BAF) at room temperature. The results showed that gas water ratio (GWR) at the optimal operation time was 15:1under the condition of inlet ammonia nitrogen (NH₄⁺-N) concentration of 400mg/L and reflux ratio of 1:1, ammonia nitrogen removal rate (ARE) was over 90%,total nitrogen (TN) removal load was 1.1kgN/(m³·d), and TN removal rate could reach 83%. When the GWR is 15:1,the DO is controlled around 2.41mg/L and 4.22mg/L, the amount of NH₄⁺-N converted into nitrite (NO₂^--N) in water increased, and the ANAMMOX activity is enhanced. The real-time fluorescence quantitative PCR (QPCR) analysis of functional strains on the biofilm showed that when the GWR was 15:1, both ANAMMOX and AOB had the highest abundance, more than 10¹² copies/g dry sludge. Therefore, integrated nitrogen removal has the best effect. At the same time, studies have shown that the ANAMMOX reaction is strengthened after increasing the gas water ratio and N₂O is not generated in the ANAMMOX process. When the GWR is 15:1, the total release amount of N₂O is the smallest, and the release factor is 0.0012.