猪粪秸秆沼液短程硝化反硝化快速启动及稳定运行研究

短程硝化反硝化工艺具有节省碳源、节省曝气量、污泥产量低等优点,但由于启动时间长、短程硝化效果不稳定等问题限制了其工程应用。针对此问题,本研究采用泥膜一体化工艺(IFAS)处理猪粪秸秆沼液,并考察了短程硝化反硝化工艺生物强化快速启动及稳定运行效果。结果表明,通过添加实验室自制氨氧化菌剂与反硝化菌剂,可在17 d内完成反应器的快速启动;稳定运行阶段,系统猪粪秸秆沼液有机负荷(COD)平均为1 040.0 mg·L~(-1)·d~(-1),好氧池平均NH_3-N负荷为110 mg·L~(-1)·d~(-1);好氧池平均NO_2~--N积累率为91.4%;COD、NH_3-N、TN平均去除率分别达到92.1%、97.0%、90.1%,且COD和TN的去除主要发生在缺氧池。分子生物学分析表明,整个运行过程中,好氧池生物膜氨氧化细菌(AOB)的丰度由0.003 6%上升至0.014 3%,增长至原来的4倍;亚硝酸盐氧化细菌(NOB)的丰度由0.004 8%下降至0,说明利用氨氧化菌剂、反硝化菌剂可快速稳定实现短程硝化反硝化脱氮工艺的启动。

Fast startup and stable operation of partial nitrification and denitrification using pig manure straw biogas slurry

The partial nitrification and denitrification process has several advantages such as carbon source and aeration energy saving and a low sludge yield, but its engineering application is limited due to its long startup time and unstable short cut nitrification performance. To solve this problem, an Integrated Fixed-Film Activated Sludge(IFAS) system was used to treat the biogas slurry of pig manure and straw, and the rapid startup and stable operation effects of short cut nitrification and denitrification with bioaugmentation were investigated. Results showed that the rapid startup of short cut nitrification and denitrification could be achieved within 17 days by adding laboratorymade ammonia oxidation and denitrification agents. During stable operation, the average organic loading rate of pig manure and straw biogas slurry was 1 040.0 mg·L^-1·d^-1, average NH₃-N loading rate in the aerobic tank was 110 mg·L^-1·d^-1, and the average NO₂^--N accumulation rate in the aerobic tank was 91.4%. The removal rates of COD, NH₃-N, and TN of the biogas slurry were reached at 92.1%, 97.0% and 90.1%, respectively, and the removal of COD and TN mainly occurred in the anoxic tank. During the whole operation period, molecular biology analysis showed that the abundance of Ammonia Oxidizing Bacteria(AOB) in aerobic tank biofilms increased from 0.003 6% to 0.014 3%(four times higher), and Nitrite Oxidizing Bacteria(NOB) abundance decreased from 0.004 8% to 0. This study shows that the rapid start and stable operation of partial nitrification and denitrification can be achieved using ammonia oxidation and denitrifying agents as inoculants.