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年度	100	專案性質	實驗性質
專案類別	研究專案	研究主題	整治
申請機構	國立高雄大學	申請系所	土木與環境工程學系
專案主持人	袁菁	職等/職稱	教授
專案中文名稱	電動力技術現地模組設立及測試之研究
中文關鍵字
專案英文名稱
英文關鍵字
執行金額
執行期間	2011/11/26 至 2012/11/25
計畫中文摘要	電動力技術係一現地(in-situ)整治技術，可藉由調整電動力操作參數及處理 時間，使得地面活動及原有建物不受影響，且因具備外在驅動力及污染物擴散方 向可控制之特點，特別適合應用於大多技術不適合處理之黏土層污染。其主要優 勢為：(1)可產生均勻之電滲透流於異質且低滲透性之土壤介質中移動，(2)可有 效控制電滲透之流向，(3)高降解率與移除率且具安全性，(4)為一種高經濟效益 之現地永續處理技術(Li et al.,1998，Pamukcu et al., 1997)。落實實場整治，建立 本土現地操作參數，將可有效解決現有污染場址之技術瓶頸。 本研究之目的是為設計一電動力現地三維模組，並進行一系列之土壤整治 實驗，探討電極接觸面積及電位坡降對土壤整治效率之影響。討論模組之設計 標準。最終定案要點為： 1. 模組尺寸大小設計為1.5 m × 1 m × 1.1 m，且為可移動性； 2. pH值自動控制裝置； 3. 實驗過程中需對pH值、導電度及電流/電壓監測。 本研究實驗所使用之電極棒為空心不銹鋼棒(SUS 316)，操作流質之選用為 0.05 M之乳酸(Lactic acid)，整治時間為20天，電位坡降為0.2~0.35 V/cm，電極 接觸面積為28,260~37,680 cm2 ，以探討電極接觸面積及電位坡降之影響。 在Test 1實驗中電滲透流係數(Ke)為23.9 cm2 /V-s，其Zn、Cu、Pb、Cr及Ni金 屬之去除效率分別為82.4 %、81.9 %、51.6 %、88.1 %及44.9 %，主要是藉由電 滲透流及離子遷移方式移除目標污染物，在陰極槽液中發現有少量污染物濃度， 並推測其主要污染物皆因電鍍而在陰極電極上被發現；而在目標污染物Cu之序 列萃取中發現，在電位坡降為0.35 V/cm時可有效改變其與土壤之鍵結型態，並 藉由電滲透流及電子遷移方式移除；相較於Test 2實驗(Ke)為23.9 cm2 /V-s，其Zn、 Cu、Pb、Cr及Ni金屬之去除效率分別為41.8 %、4.2 %、32.8 %、31.6 %及35.6 %， 而與Test 1相同的是實驗結束後發現陰極電極有金屬污染物鍍於外層，使電極重 量增加，而比較對污染物之去除效率即可發現，當降低電位坡降為0.2 V/cm時， 將無法有效達到去除之成效，且在Cu之鍵結型態分析中，降低電位坡降以致無 法有效改變其鍵結型態達到移除之成效，但在殘留濃度分佈中仍可發現有緩慢 往陰極移動之現象。 比較Test 1及Test 2之殘留濃度分佈可發現，本研究之三維模場污染物移動方式有別於一般實驗室小型模組模擬實場整治情形，除了一般由陽極往陰極移 動之縱向去除外，明顯可看出本研究之試驗仍有一垂直向往上移動之現象發生， 推測應是模擬實場整治，在模場上方無額外施加壓力，以致在電動力整治過程 中產生之氣體往上逸散時，同時將污染物往上推動所造成；另在土壤溫度量測 部分，平均室溫為32.1 ℃，期末土體平均溫度為36.6 ℃，土體溫度量測結果 平均高於室溫4~5 ℃，是一可接受之範圍。 而在成本考量方面，電極費用佔總成本之85 %、操作流質費用佔14 %，電 極是主要影響成本多寡之主因(本研究電極以每次試驗接更新計算)，而主要電 極之消耗原因為槽液腐蝕及電流造成之氧化腐蝕情形，因此若能有效控制pH值 及藉由試驗找出一最佳操作參數，即可使電極重複使用，將可有效降低整治成 本。
計畫英文摘要	Electrokinetic (EK) process is classified as an in-situ remediation technology. It will be conducted in site without disturbing present resident activities with proper operation and reasonable treatment time. EK process is much fit in contaminated site with clay soil because pollutant will be forced to migrate by the electrical driving force. The advantages EK process includes： (1) production of uniform electroosmosic flow in heterogenous medium, especially in low permeable soil; (2) easy control of flow direction; (3) high removal and degradation efficiency; (4) high economy. To establish pilot-scale operation parameters will be beneficial to promote in application The aim of this project is to design a 3-D pilot-scale EK modul and conduct a series of soil remediation experiments to investigate the effect of electrode area and potential gradient on remediation efficiency. The 3-D pilot-scale EK modul was set up as follows, - The size of 3-D modeul is 1.5 m x 1m x1m, with mobile function; - The reservoir pH was maintained at a range of 6~8 to prevent clogging of metal precipitates; - The reservoir pH, reservoir/soil temperature, and electro current were continuously monitored throughout the experiments. Considering reducing cost, hollow stainless electrodes (SUS 316) are selected for test. A series of the experiments were conducted with 0.05 M lactic acid as processing fluid under potential gradient of 0.2~0.35 V/cm and electrode area of 28260 ~ 37680 cm2 for 20 days. Results showed that the treatment efficiency of Zn, Cu, Pb, Cr and Ni were 82.4 %, 81.9 %, 51.6 %, 88.1 % and 44.9 %, respectively, conducted with potential gradient of 0.35 V/cm and electrode area of 28260 cm2 . As decreased to potential gradient to 0.2 V/cm, the treatment efficiency of Zn, Cu, Pb, Cr and Ni were also decreased to 41.8%, 4.2 %, 32.8 %, 31.6% and 35.6 %, respectively. It was found that most of removed pollutants are coating on the cathode electrode surface and part of remained in the cathode reservoir. It was concluded that the treatment mechanism was dominated by EO flow. Based on sequential extraction results, it was found that the binding strength of Cu with soil was shifted from to strong to weak after EK process and, however, it became insignificant at lower potential gradient. Other than pollutants migrated from anode to cathode, it was also found that the pollutants were migrated from bottom layer to top layer. Such vertical migration of pollutants will be beneficial to remediate contamination in depth. The soil temperature after EK treatment was 4~5 ℃ higher than room temperature which was at reasonable range for in-situ remediation. For cost analysis, 85%, 14%, and less than 1% was accounted for the cost of electrodes, processing fluid and electricity, respectively. To prevent corrosion of electrode would tremendously lower the remediation cost.