| 摘要: | 隨著居住地、工業與農業之快速發展，有大量氮污染物排放至承受水體中，導致淡水生態系統優養化，嚴重地威脅到了水生生物以及人們之健康安全。且國內法規對於排放水之水質要求也越加嚴格，為了達到法規所限制之放流水標準，對污水處理廠處理程序和性能之探討為必要事項。
本研究以模型廠操作OAO生物去氮程序（Oxic-Anoxic-Oxic，好氧-缺氧-好氧），模型廠設置於桃園北區水資源中心。由操作結果探討OAO程序對水中污染物之處理效能、合適之操作範圍以及探討污泥吸附有機物之利用特性。
在HRT為10~12小時之條件下，COD、BOD、氨氮、總氮之去除率分別可達80%、90%、90%、60%以上，整體效果均符合放流水標準。但由各階段不同之第一段-好氧槽（硝化槽）水力停留時間（HRT）結果顯示，應至少設計達6小時之HRT以達良好之硝化效率。好氧：缺氧：好氧為5:4:1之分配對於氮之去除能有較佳且穩定之能力，提供缺氧槽足夠體積以提高殘餘溶氧之衝擊承受度，能夠有效提升脫硝能力。經研究結果，建議設計參數HRT調整為10～16小時、F/M值為0.05~0.15 kg BOD/kg MLSS∙d、ASRT為15～30天，作為設計準則。
由吸附試驗結果可得知活性污泥在消耗完系統內之有機物之後，能將吸附於表面之有機物進行水解反應以獲取能量以供生物成長。且將比脫硝速率（SDNR）數值以及由質量平衡得出之系統比脫硝速率進行比較，顯示水解作用能夠使後脫硝配置之系統擁有前脫硝配置之脫硝潛力。代表OAO程序之核心，活性污泥利用所吸附之緩慢可生物分解COD（SBCOD）及積蓄於細胞內之有機物作為碳源進行脫硝具可行性。
試驗中不同之F/M操作下皆能得到良好之污染物去除率，顯示OAO程序之操作彈性大。但由吸附試驗可得知較高之F/M能使水解作用之有機物利用效率更高，因此F/M對OAO程序效率之影響於未來需作更深入之探討。
;With the rapid development of residential, industrial, and agricultural sectors, a considerable amount of nitrogen pollution is being released into receiving water bodies, causing eutrophication of freshwater ecosystems and posing a serious threat to aquatic organisms as well as human health and safety. Furthermore, domestic regulations regarding the water quality requirements for discharged water have become stricter. Therefore, it is vital to investigate the treatment processes and performance of wastewater treatment plants to meet the discharge standards set by regulations.
The purpose of this research is to investigate the performance of the Oxic-Anoxic-Oxic (OAO) biological nitrogen removal process with a pilot plant at Taoyuan North District Water Resource Center. The designed flow rate of the pilot plant is 3-4 CMD. The study investigates the OAO process′s pollution removal efficiency and proposes suitable operation parameter ranges. It also looks into the utilization characteristics of sludge surface-adsorbed organic matter.
Under a hydraulic retention time (HRT) of 10-12 hours, the removal rates of COD, BOD, ammonia nitrogen, and total nitrogen are all above 80%, 90%, 90%, and 60% respectively, meeting the discharge criteria. However, the results of various HRTs indicate that a minimum HRT of 6 hours of the first oxic tank should be designed to ensure sufficient reaction time for nitrification. The distribution of oxic:anoxic:oxic tanks at a ratio of 5:4:1 demonstrates better and more stable nitrogen removal capability, providing sufficient volume for the anoxic tank to enhance the tolerance of residual dissolved oxygen, thereby effectively improving denitrification capacity. Based on the research results, it is recommended to adjust the design parameters as follows: HRT of 10-16 hours, F/M value of 0.05-0.15 kg BOD/kg MLSS∙d, and an aerobic sludge retention time (ASRT) of 15-30 days, as design guidelines.
The adsorption test results reveal that after the consumption of organic matter in the system, activated sludge can hydrolyze the adsorbed organic matter on its surface to obtain energy and support microbial growth. Furthermore, comparing the specific denitrification nitrate removal (SDNR) value to the system-based denitrification rate derived from mass balance, it is evident that hydrolysis of SBCOD(slowly biodegradeble COD) enables the post-denitrification configuration to possess a denitrification potential similar to the pre-denitrification configuration. This indicates the viability of using adsorbed SBCOD and organic matter storaged in activated sludge cells as carbon sources for denitrification in the OAO process.
In this study, good pollutant removal rates were obtained under various F/M conditions, making it difficult to determine the effect of F/M on the OAO process. However, the adsorption test indicates that higher F/M values result in higher utilization efficiency of organic matter in hydrolysis process. As a result, future research should conduct to investige the effect of F/M on the efficiency of the OAO process. |
