有机负荷波动频次对好氧颗粒污泥的影响

为了探究在低强度进水条件下有机负荷波动频次对好氧颗粒污泥（aerobic granular sludge，AGS）的影响，设置3个序列间歇式反应器（sequence batch reactor，SBR）R1、R2和R3，以合成配水为基质，高低有机负荷率（organic load rate，OLR）分别为0.67g/(L?d)、0.67g/(L?d)，0.74g/(L?d)、0.56g/(L?d)，0.74g/(L?d)、0.56g/(L?d)；定义有机波动频次为每12天完成高低OLR波动的次数，R1的OLR恒定，R2、R3分别每12天、4天完成一次OLR的高低波动，波动频次分别为0、1、3。由实验结果可知，R1、R2和R3的平均粒径分别可达到318.86μm、426.71μm、593.06μm，胞外聚合物（extracellular polymeric substance，EPS）含量（以volatile suspended solids，VSS计）可达到71.97mg/g、75.88mg/g、80.35mg/g，蛋白质/多糖（protein/polysaccharide，PN/PS）分别为4.24、5.14、5.72，表明波动频次为3时颗粒具有更高的疏水性、稳定性。此外R1、R2、R3的内碳源储存率（internal carbon storage rate，CODin）、同步硝化内源反硝化（simultaneous nitrification internal denitrification rate，SND）率分别为97.06%和44.74%、98.37%和58.20%、98.91%和64.42%、总磷（total phosphorus，TP）平均去除率分别为86.82%、89.36%、92.65%，总氮（total nitrogen，TN）平均去除率分别为71.69%、74.31%、78.55%，说明波动频次为3时颗粒具有更高的碳源利用率与污染物去除能力。

Effect of organic load fluctuation frequency on aerobic granular sludge

In order to explore the influence of organic load fluctuation frequency on aerobic granular sludge (AGS) under low-intensity influent conditions, three parallel cylindrical sequencing batch reactors(SBR), R1, R2 and R3, were operated by constant organic loading rate (OLR) and two alternating OLR modes respectively, fed with synthetic water. Their high and low OLR were 0.67gCOD/(L?d)/0.67gCOD/(L?d), 0.74gCOD/(L?d)/0.56gCOD/(L?d) and 0.74gCOD/(L?d)/0.56gCOD/(L?d) respectively. The fluctuation frequency of organic load was defined as the number of OLR high-low fluctuation every 12 days, R1’s OLR did not fluctuate, R2 and R3 completed OLR high-low fluctuation every 12 days and 4 days respectively, and their fluctuation frequencies were 0, 1 and 3 respectively. The results showed that the average particle sizes of R1, R2 and R3 were 318.86μm, 426.71μm and 593.06μm, respectively. The extracellular polymeric substance (EPS) content (VSS) were 71.97mg/g, 75.88mg/g and 80.35mg/g, PN/PS were 4.24, 5.14 and 5.72, respectively, indicating that the granules had higher hydrophobicity and stability when the fluctuation frequency was 3. In addition, the internal carbon storage rates (COD_in) of R1, R2 and R3 were 97.06%, 98.37%, 98.91%, respectively, and the internal carbon storage rate (SND) efficiencies were 44.74%, 58.20%, 64.42%, respectively. The average total phosphorus (TP) removal efficiencies were 86.82%, 89.36% and 92.65%, respectively, the average total nitrogen (TN) removal efficiency were 71.69%, 74.31% and 78.55%, respectively, indicating that the granules had higher carbon source utilization efficiency and pollutant removal ability when the fluctuation frequency was 3.