本研究針對四氯乙烯飽和污染土壤,採用電動力結合零價鐵處理技術,透過電滲透流驅使飽和土壤層中滲透水往陰極方向流動,當四氯乙烯流經零價鐵,藉由零價鐵之還原脫氯機制來降解四氯乙烯污染濃度,有效整治飽和層中土壤及孔隙水。本研究採用實驗室規格與模場規格分別進行操作試驗,其規格分別為26cm x 11cm x 11cm以及150cm x 63cm x 63cm,實驗室規格採用三種不同電壓梯度,飽和污染土壤於操作168小時下,電壓梯度分別為1 V cm-1,2 V cm-1,3 V cm-1條件下,其四氯乙烯去除率分別約60%;78%;86%,計算每日平均降解率,電壓梯度1 V cm-1、2V cm-1、3 V cm-1分別為,0.3 mg / kg day、0.39 mg / kg day、0.44 mg / kg day,其關聯式為每日平均降解率=0.07電壓梯度+0.2367,另外,為模擬現地整治之處理技術,放大72倍進行模場規格試驗,於操作336小時,電壓梯度1 V cm-1下,飽和土壤層中降解效率為89.1%,模場規格每日平均降解率為0.31 mg / kg day,而孔隙水之去除率約為83%,本研究方法能有效同時降解飽和層中土壤與孔隙水。將實驗室規格與模場規格於相同之操作條件下進行比較,於不同之試驗尺寸但相同電壓梯度、時間下,電動力結合零價鐵對於四氯乙烯之降解效率,未因改變尺寸而受到影響。
This research focused on the remediation performance of electrokinetics integrated zero-valent metals for perchloroethylene (PCE) contaminated soils. Under the effect of electric field, electroosmotic flow and ion migration occurred. These reactions drove the water from positive electrode to negative electrode, which desorbed PCE from the soil phase into aqueous phase. When PCE flowed through zero-valent metals, the reductive dechlorinating mechanisms of zero-valent metals would degrade the PCE concentration. It would remediate the soil effectively. Experiments were made in two different scales, Lab scale and Pilot scale. The length, width and height of lab scale and pilot was 26cm x11cm x11cm and 150cm x 63cm x63cm respectively. The experiments were made under 3 different voltage gradient, 1 V cm-1, 2 V cm-1 and 3 V cm-1 . After 168 hours of treatment under 1 V cm-1 of voltage gradient, the removal efficiency of PCE was approximately 60%. After 168 hours of treatment under 2 V cm-1 of voltage gradient, the removal efficiency of PCE was approximately 78%. After 168 hours of treatment under 3 V cm-1 of voltage gradient, the removal efficiency of PCE was approximately 86%. The average removal efficiency under 1 V cm-1, 2 V cm-1 and 3 V cm-1 was 0.3 mg/kg day, 0.39 mg/kg day and 0.44 mg/kg day respectively. The experiment results showed that electrokinetics integrated zero-valent metals can effectively remediate PCE. Voltage gradient is also an important factor for the removal efficiency of PCE. In order to simulate the practical usage of this method towards actual situation, pilot scale experiments, which were 73 times larger in scale, were made. Sampling holes were set under the container. After 336 hours of treatment under 1 V cm-1 of voltage gradient, the removal efficiency of PCE was approximately 89% and 83% in saturated soil and interstitial water respectively. The experiment results showed that electrokinetics integrated zero-valent metals can effectively remediate PCE in both the saturated soil and the interstitial water. After comparing the data from lab scale experiments and pilot scale experiments, the results were found. The remediation performance of PCE in the saturated soil in lab scale experiment was approximately 0.3 mg/ kg day. The remediation performance of PCE in the saturated soil in pilot scale experiment was approximately 0.31 mg/ kg day. The above results showed that the remediation performance of PCE can remain stable and effective in different experiment scale under the same voltage gradient and duration. After the successful result in the experiments, we speculated that we could develop fast, efficient and cost-effective PCE remediation technique under our successful experiments data and results.
為了持續優化網站功能與使用者體驗,本網站將Cookies分析技術用於網站營運、分析和個人化服務之目的。
若您繼續瀏覽本網站,即表示您同意本網站使用Cookies。