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年度	112	專案性質	非實驗性質
專案類別	模場試驗	研究主題	調查
申請機構	國立陽明交通大學	申請系所	環境科技與智慧系統研究中心
專案主持人	周珊珊	職等/職稱	約聘研究員
專案中文名稱	應用地下水抽出處理(P&T)系統搭配預濃縮以可再生型吸附顆粒(RAP)削減地下水中PFAS
中文關鍵字	可再生型吸附顆粒, 中空纖維納濾,地下水抽出處理
專案英文名稱	Application of pump-and-treat (P&T) system coupled with pre-concentration and regenerative adsorption particles (RAP) to reduce PFAS in groundwater
英文關鍵字	RAP,hollow fiber NF,P&T
執行金額	2,592,000元
執行期間	2024/1/1 至 2025/12/31
計畫中文摘要	全氟/多氟烷基化合物(per- and polyfluoroalkyl substances, PFAS)為持久性有機污染物，具有疏油疏水、熱穩定和化學穩定等特性，難以自然衰減且長期存在於環境中，對人類健康有負面影響。聯合國自2009年起通過斯德哥爾摩公約，逐步禁止與限制多種 PFAS 的使用。台灣已在半導體、染整和電鍍業等行業周遭環境中，如放流水或地下水，檢測出PFAS污染，因此迫切需要研發適當的處理技術。 本計畫係採用三種不同的處理技術於潛在污染場址削減PFAS，分別為可再生型吸附顆粒(regenerative adsorption particles，簡稱RAP)、中空纖維納濾膜(hollow fiber NF)及地下水抽出處理系統(P&T)。RAP係以活性碳為基底，表面披覆薄層的貴金屬氧化物，具極佳的吸附與氧化還原特性，並可再生循環使用，已證實用於地下水LNAPL污染物移除已獲有不錯的成效。另外考量地下水中PFAS濃度極低，因此採用中空纖維NF進行預濃縮再搭配RAP進行處理，中空纖維NF較傳統卷式納濾膜具備進水水質預處理要求低且可反洗等特性；國外研究學者亦證實NF對PFAS污染物皆有極佳的截留率，值得深入探討。本計畫使用的P&T系統為一新型專利系統，有別於傳統抽水處理方法，具有占地面積少、方便移動、易維修保養並可同時移除自由相浮油等優點。 本計畫掌握環境部地下水計畫歷次地下水PFAS濃度相對較高區域，該區位在某工業區污水處理廠區域，其地下水PFOA及PFOS調查濃度皆大於美國環保署2016年訂定PFOA或/及PFOS終生健康建議值0.00007 mg/L，且為PFOS歷次調查濃度最高點位，因此選定此標的區位為模場試驗地點。本計畫第一年主要構想為運用P&T搭配RAP進行高級氧化處理，經水力控制將改善之水體回注，以達到去除地下水PFAS的目標；第二年規劃在P&T後使用中空纖維NF，以預濃縮的方式，擬增加較第一年多一倍的抽水量，試驗在地下水PFAS濃度相對較低條件下的應用成效，並評估地下水PFAS的去除效率及優化實務操作參數，進一步評估整體系統的處理效果。 在實驗室試驗部分，除了建立LC/MS/MS的PFAS分析方法外，並進行以下幾項RAP相關處理技術之評估，包括RAP對PFAS吸附容量、RAP催化氧化可行性試驗、吸附/催化氧化及再生試驗等，以完成RAP技術削減PFAS成效評估。我們發現RAP具有與原始活性碳相當的PFAS吸附容量；在最重要的吸附/催化氧化及再生試驗中，發現使用 RAP 技術搭配不同氧化促劑削減 PFAS 成效顯著，其中臭氧曝氣反應最快(0.5小時)，其次為雙氧水輔以空氣曝氣(4小時)，空氣曝氣則需48小時。同時，我們僅在RAP配合空氣曝氣處理PFOA時，觀察到極少量的PFAS中間產物生成，其他組未見中間產物，顯示這與促進劑的氧化能力相關。另外，經由NF膜的預濃縮試驗，發現藉由兩段式NF串聯方式，可將PFHpA (C7)及PFOA(C8)的濃縮倍數大幅提升至11.7及45.9倍。 在模場試驗部分，本團隊建置了一口抽水井、一口注水井及RAP設備，並於七月開始運轉及進行採樣分析。結果顯示，八種 PFAS化合物在試驗第二個月濃度上升，推測原因可能是水力牽引加上地勢低及鋼板結構阻水，或颱風季大量雨水滲入帶入土壤中的PFAS。於現場RAP設施運轉三個月數據顯示，除PFOS濃度和前一個月差不多外，其餘PFAS濃度皆開始下降，已初步看見成效，後續團隊將持續追蹤。另為快速了解RAP對現場地下水中PFAS的處理效果，因此我們另行取現場水樣，先以NF濃縮至少50倍後，模擬模場試驗的方式，進行2天的小型連續流管柱實驗，確認PFOS可由1 ppm降至0.2 ppm左右，發現和實驗室吸附/催化氧化及再生試驗的結果相當。 根據以上各項可行性評估結果，初步判斷未來可以藉由NF膜的預濃縮效應，並搭配氧化促進劑輔助RAP進行吸附和催化氧化，達到持續再生RAP及削減 PFAS的目標。由再生效率與氧化功能指標顯示出一致的變化趨勢，進一步驗證了 RAP的吸附、催化氧化和再生程序能保持其活性，且可重複使用，因此適合作為處理地下水中PFAS的解決方案。
計畫英文摘要	Per- and polyfluoroalkyl substances (PFAS) are persistent organic pollutants characterized by their oil and water repellency, thermal stability, and chemical stability. They are difficult to naturally degrade and can persist in the environment for a long time, negatively impacting human health. Since 2009, the United Nations has implemented the Stockholm Convention to gradually ban and restrict the use of various PFAS. In Taiwan, PFAS contamination has been detected in environmental media surrounding industries such as semiconductors, dyeing and finishing, and electroplating, particularly in effluents and groundwater. Therefore, there is an urgent need to develop suitable treatment technologies. This project will apply three different treatment technologies to reduce PFAS at potentially contaminated site. These technologies include regenerative adsorption particles (RAP), hollow fiber nanofiltration membranes (hollow fiber NF), and pump-and-treat groundwater extraction systems (P&T). RAP is a regeneratable precious metal oxide catalyst based on activated carbon, has superior adsorption, redox property, and advantages in recyclability. RAP has been demonstrated to effectively remove LNAPLs in groundwater. Considering the extremely low PFAS concentration in groundwater, hollow fiber NF will be used for pre-concentration, combined with RAP for treatment. The hollow fiber NF has the advantages such as low inlet water quality requirements and backwashing capability compared to the traditional spiral-wound NF. Foreign studies have shown that NF have high trapping efficiency of PFAS, making it more promising for further exploration. The P&T used in this project is a newly patented system, distinguished from traditional air-lift and water-lift treatment methods. It is easily transportable, and not only requires less space but also minimal maintenance. Additionally, it can simultaneously remove free-phase floating oil. This project aims to identify areas with relatively higher concentrations of PFAS in groundwater, the area near the wastewater treatment plant of one industrial park. The concentrations of PFOA and PFOS in the groundwater in this area are both higher than the lifetime health advisory levels of 0.00007 mg/L set by the US Environmental Protection Agency in 2016. This location represents a prime testing site due to its historical high concentrations of PFOS. The primary concept for the first year of the project is to use pump and treat (P&T) in conjunction with RAP for advanced oxidation treatment. Treated water will be reinjected into the aquifer under hydraulic control to achieve the goal of removing PFAS from the groundwater. In the second year, the plan is to use hollow fiber nanofiltration (NF) after P&T for pre-concentration. This involves doubling the pumping rate compared to the first year and testing the application effectiveness under conditions of relatively lower PFAS concentrations in the groundwater. The project will evaluate the efficiency of PFAS removal and optimize practical operating parameters, further assessing the overall effectiveness of the treatment system. In the laboratory experiments, we not only established the LC/MS/MS analytical method for PFAS but also evaluated several RAP-related treatment techniques. These include assessing RAP's PFAS adsorption capacity, feasibility tests for RAP catalytic oxidation, and adsorption/catalytic oxidation and regeneration tests, all aimed at evaluating the effectiveness of RAP technology in reducing PFAS. We found that RAP has a PFAS adsorption capacity comparable to that of original activated carbon. In the crucial adsorption/catalytic oxidation and regeneration tests, RAP technology combined with different oxidizing accelerating agents showed significant PFAS reduction effects. Ozone aeration had the fastest reaction time (0.5 hours), followed by hydrogen peroxide with air aeration (4 hours), while air aeration alone took 48 hours. Additionally, we observed only trace amounts of PFAS intermediate products during PFOA treatment with RAP and air aeration, while no intermediates were found in the other groups, indicating that this outcome is related to the oxidizing power of the agents used. Additionally, through the pre-concentration tests using two-stage NF series system, the concentration factors of PFHpA (C7) and PFOA (C8) were significantly increased to 11.7 and 45.9 times, respectively. In the pilot field test, our team established one extraction well, one injection well, and RAP equipment, and began operations and sampling analysis in July. The results showed that the concentration of eight PFAS compounds increased during the second month of the test. This may be due to hydraulic pull combined with the area's low location and steel structures blocking water flow, or from the infiltration of rainwater during the typhoon season, carrying PFAS from the soil into the groundwater. Data from three months of operation at the on-site RAP facility indicate that PFOS concentration keeps almost the same compared to the previous month, while all other PFAS concentrations have decreased. This shows preliminary effectiveness, and the team will continue to monitor the situation. To quickly assess the effectiveness of RAP in treating PFAS in the groundwater, we collected additional site water samples, concentrated them at least 50 times using NF, and conducted a two-day small-scale continuous flow column experiment simulating the field conditions. The results confirmed that PFOS could be reduced from 1 ppm to about 0.2 ppm, consistent with the results of laboratory adsorption/catalytic oxidation and regeneration tests. Based on the feasibility assessments, it is preliminarily estimated that the NF membrane pre-concentration effect can be utilized in the future. By combining this with the use of oxidizing accelerating agents to assist RAP in adsorption and catalytic oxidation, RAP can be continuously regenerated, achieving PFAS reduction. The consistent trend between regeneration efficiency and oxidation function index further verifies that the adsorption/catalytic oxidation, and regeneration processes of RAP can maintain its activity, allowing it to be reused. Therefore, RAP is suitable as a solution for treating PFAS in groundwater.