礫間設施處理效能評估之研究

近年來，政府推動的「前瞻基礎建設計畫」-水環境建設是其中一環，主要分成水與發展、水與安全及水與環境三大建設主軸。在這其中，水環境改善計畫成為重要的焦點，特別是河川污染改善工作。為了有效提升河川水體水質，政府在公共污水下水道普及之前，採用了現地處理設施的階段性方案淨化生活污水。有效改善河川水質，同時也降低環境污染的負荷。目前全台地區已陸續興建超過60座礫間淨化設施，截至112年底止，雙北及桃園地區已建置20餘座，其中多座礫間淨化設施已運作超過10年。本研究的目標在於評估礫間接觸曝氣氧化設施在處理水質方面的效能，透過收集各礫間的水量和水質數據資料，並進行整理和分析，項目包括生化需氧量(BOD5)、氨氮(NH3-N)、懸浮固體物(SS) 等。透過操作時間與污染物去除率作比較分析，得到設施處理效能設計值與實際值比較結論，各規模設施的BOD5實際去除率平均值86%比設計去除率平均值75%高出11%， NH3-N實際去除率平均值93%比設計去除率平均值78%高出15%， SS實際去除率平均值88%比設計去除率平均值76%高出12%。另外探討處理水量達成率與污染物去除率分析結果顯示，不同規模的礫間設施(小型、中型、大型)，都能達到預期的污染物去除率。具體而言，小型設施的BOD5、NH3-N、SS平均去除率超過88%，中型設施則超過85%，而大型設施的BOD5、NH3-N、SS平均去除率超過86%。總結而言，本研究的結果有助於了解礫間設施在長期運行中的效能，期望有助於機關在執行督導評鑑時，更準確評估礫間設施之處理效能，亦可供機關在後續對其他案場的規劃設計審查時作為參考，間接影響工程建造、監造工作和設計作業等預算規劃。

關鍵字

礫間接觸氧化法；處理水量達成率；污染物去除率

並列摘要

In recent years, the Taiwanese government has launched Forward-looking Infrastructure Development Program. Water environments to build resilience against climate change, is one of the funding categories, expedites construction of infrastructure for water remediation, water supply and water recreation purposes. Water remediation has become an important aspect, particularly addressing river pollution. Before the widespread implementation of public sewage systems, the government uses temporary on-site treatment facilities to purify domestic wastewater, which improve river water quality and reduce the burden of environmental pollution efficiently. Nowadays, there are more than 60 gravel water purification facilities in Taiwan. By the end of 2023, more than 20 facilities will have been constructed in the greater Taipei and Taoyuan areas. Additionally, more than 10 years have passed since most of the facilities began operation. This study evaluated the water quality treatment effectiveness of the gravel water purification facility, including analysis of parameters such as biochemical oxygen demand (BOD5), ammonia nitrogen (NH3-N), and suspended solids (SS). Comparative analysis between operational duration and pollutant removal rates reveals that actual removal efficiencies exceed design expectations. Specifically, across various facility scales, the average BOD5 removal rate of 86% exceeds the design rate of 75% by 11%, while NH3-N removal averages 93%, surpassing the design rate of 78% by 15%, and SS removal averages 88%, surpassing the design rate of 76% by 12%. Furthermore, analysis of capacity realization and pollutant removal rates showed that treatment consistently met expected pollutant removal rates regardless of capacity realization. Specifically, the average removal rates of BOD5, NH3-N, and SS exceed 88% in small facilities, 85% in medium-sized facilities, and 86% in large-scale facilities. In summary, this study provides insights into the long-term operational efficiency of gravel water purification facilities. It is expected to help regulators accurately assess the performance of these facilities during monitoring and evaluation processes, and to provide references for future budget allocations in project planning, engineering construction, supervision, and other site design reviews.