School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou, 730070, PR China; Technical Center of Sewage Treatment Industry in Gansu, Lanzhou, 730070, PR China.
School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou, 730070, PR China; Technical Center of Sewage Treatment Industry in Gansu, Lanzhou, 730070, PR China.
Chemosphere. 2024 Sep;364:143222. doi: 10.1016/j.chemosphere.2024.143222. Epub 2024 Sep 3.
Anammox bacteria (AnAOB) can be easily enriched under high temperatures and high substrate concentrations, while the application of the mainstream anammox process in low substrate municipal sewage is still relatively uncommon. Therefore, this study investigated the enrichment of AnAOB under conditions of low ammonia nitrogen and nitrite concentration at 25 °C. Results showed that using inoculated aerobic sludge, four ASBRs (R1, R2, R3 and R4) were successfully initiated with different influent substrate (NO-N/NH-N) ratios of 1.2, 1.32, 1.4 and 1.5, respectively, with reactor start-up times were 162, 150, 120 and 134 days, respectively. The values of ΔNO-N/ΔNH-N in reactors were stable at 1.17, 1.32, 1.43 and 1.53 respectively. The increase in influent substrate ratios resulted in improved TN removal rates and accelerated consumption of chemical oxygen demand (COD) during the initial start-up stage. The maximum TN removal rates achieved in the four reactors were 76.09%, 79.24%, 82.82% and 82.63%, respectively. The color of sludge gradually changes from yellowish-brown to reddish-brown. Furthermore, the surface of sludge exhibited a porous mineral structure, with crater-like cavities. The dominant anammox species in the system was identified as Candida Brocadia (3.04%). According to qPCR, the abundance of hzsB in the system is 1.65 × 10 copies/g VSS, confirming the effective enrichment of AnAOB.
在高温和高基质浓度下，厌氧氨氧化菌（AnAOB）很容易得到富集，而主流的厌氧氨氧化工艺在低基质城市污水中的应用仍然相对较少。因此，本研究考察了在 25°C 下低氨氮和亚硝酸盐浓度条件下富集 AnAOB 的情况。结果表明，采用接种好氧污泥，通过控制不同的进水基质（NO-N/NH-N）比（分别为 1.2、1.32、1.4 和 1.5），成功启动了四个序批式厌氧生物膜反应器（ASBR）（R1、R2、R3 和 R4），启动时间分别为 162、150、120 和 134 天。各反应器中ΔNO-N/ΔNH-N 值稳定在 1.17、1.32、1.43 和 1.53 左右。随着进水基质比例的增加，TN 去除率提高，COD 也在初始启动阶段得到了快速消耗。四个反应器中最大的 TN 去除率分别达到了 76.09%、79.24%、82.82%和 82.63%。污泥的颜色逐渐从黄棕色变为红棕色。此外，污泥表面呈现出多孔的矿物结构，具有火山口状的空腔。系统中优势的厌氧氨氧化物种被鉴定为 Candida Brocadia（3.04%）。根据 qPCR 结果，系统中 hzsB 的丰度为 1.65×10 copies/g VSS，证实了 AnAOB 的有效富集。
