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年度	107	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	國立屏東科技大學	申請系所	環境工程與科學系
專案主持人	陳冠中	職等/職稱	教授
專案中文名稱	以光纖光催化技術處理地下水中三氯乙烯：噸級系統處理效果研究與透水性反應牆裝置評估
中文關鍵字	光催化透水性反應牆、覆膜光纖、噸級土壤箱、三氯乙烯、現地整治
專案英文名稱	Photocatalysis of Trichlorethylene in Groundwater with Optical Fibers: Study of Treatment Efficiency of the Ton-class System and Evaluation of Permeable Reactive Barrier.
英文關鍵字	photocatalytic permeable reactive wall, coated optical fiber, ton-class soil box, trichloroethylene, in-situ remediation
執行金額	1,020,000元
執行期間	2018/1/10 至 2018/11/30
計畫中文摘要	本年度係以模擬現地污染場址整治之噸級土壤箱反應槽進行試驗，結合先前年度研究成果，利用無機覆膜液搭配噴霧塗佈法增強光纖覆膜效率及光觸媒均勻分佈性，以分層嵌入工法建立PRB。本年度以光纖光催化處理系統擴大至噸級規模，探討光纖分層嵌入施工法所需之重要參數，並且設計系統光源所需之風冷模組系統，以幫助系統有效散熱。本研究規劃以不同光源種類及光源波長進行試驗，搭配改質之光觸媒進行可見光光催效率之探討，藉以評估後續現地使用太陽光進行光催化之可行性。本研究由原先bench scale規模scale up到pilot system前所必須進行之模擬試驗，用以測試和分析未來實場應用之系統規劃和設計重點。本團隊為更進一步提升光纖光催化在現地運用之可行性，使用不同條件製備之氮改質光觸媒(N-doped TiO2)，進行後續觸媒之反射率、吸收率、能隙、以及光催化去除三氯乙烯效率之比較。由實驗結果得知，經氮改質之光觸媒，可有效增加觸媒在可見光之吸收率，提升光觸媒在可見光之光催化效率。另外，光觸媒最佳製備條件為10 mL氨水添加量之N-doped TiO2，若繼續提升添加量會使去除效率受到抑制，故後續實驗以10 mL N-doped TiO2與P25 TiO2進行比較。 在噸級反應槽試驗方面，研究探討不同燈源對於本系統處理TCE效率之影響。結果顯示Hg燈源因主要波長位於紫外光波段，在光纖光催化反應牆前後(D-E)取樣結果發現，去除TCE效率皆高於Xe燈源。另外，在A、B、C取樣口可發現，TCE去除率較無規律性，但最終結果顯示，當以分層施工法進行光纖佈置，可有效提高A、B、C三層之去除效率，進而提高整體光纖光催化反應牆之去除效果。在不同光觸媒實驗之數據顯示，以固定Hg燈源的條件下進行試驗，發現2種光觸媒對於TCE之去除效率，在反應牆前後(D-E)取樣分析發現，經過改質之光觸媒(N-TiO2)皆優於商業化之P25 TiO2。而以分層施工法對於光催化反應牆去除TCE之影響進行探討，可得TCE污染物流經光纖光催化反應牆後，可有效被去除，並且會隨著光纖層數增加而使TCE去除效率提升，其中以3-layer PRB(Hg light, N-TiO2)操作條件為最佳，可達到91%之去除效率。最後，本團隊探討上述操作設置條件對地下水中總有機碳與氯離子濃度變化之影響，結果發現光纖光催化反應牆可有效降低土壤地下水中總有機碳之含量，這也進一步證明土壤地下水污染物有效被光催化去除，並有效的將TCE降解成最終產物。
計畫英文摘要	In this project, the proposed system was used to simulate the pollution site remediation in a ton-class soil tank, using inorganic coating solution with spray coating method to enhance photocatalysts coating efficiency and to produce uniform distribution on optical fiber surface. In the past, our results show that the PRB of photocatalyst coated optical fibers performs good treatment effects on simulated groundwater polluted by TCE and has the potential to apply in on-site remediation. Therefore, we propose to expand the fiber-optic photocatalytic treatment system to the ton-class scale in this project to investigate important parameters required for the optical layered embedding method and to design the air cooling system for the system light source and help dissipate heat effectively. This study tests two types of light sources with different wavelengths and using TiO2 and nitrogen modified TiO2 to assess the feasibility of using sunlight for photocatalysis. This study scales up the pilot system after the simulation carried out on bench-scale to test and analyze important factors for its future applications. Testing and analyzing of the ton-scale system will be used to plan and design for the future field application. In order to further improve the fiber photocatalytic system, nitrogen-modified photocatalysts (N-doped TiO2) were prepared and used in the study. Their characteristics including reflectivity, absorptivity, and energy gap were determined. Treatment efficiencies of TCE by using different photocatalysts were compared. It was found that the N-doped TiO2effectively increased the absorption rate of the catalyst in visible light, and improved the photocatalytic efficiency. The preparation of N-doped TiO2 with 10 mL ammonium hydroxide obtained the optimal efficiency of TCE removal Therefore, this receipt was used for the N-doped TiO2 preparation in the following experiments. For the ton-scale photocatalytic optical fiber system, different light sources that effects the TCE removal efficiency was studied. The wavelength of the Hg lamp is located in the ultraviolet light band. Therefore, it was found that the TCE removal efficiency of Hg lamp at D and E sampling sites was higher than that of Xe lamp. On the other hand, at the A, B, C sampling sites, the TCE removal rates were less regular, but the final result shows that, the removal efficiency of TCE at A, B and C significantly improved when the layered optical fiber construction method was applied. For testing different photocatalysts, the experimental data show that using N-TiO2 as the coating of optical fiber resulted in higher TCE removal rate at D and E sampling sites than using commercial P25 TiO2 under Hg lamp illumination. Moreover, the layered construction of optical fiber PRB shows that the removal of TCE increased as the number of layer increased from single to three. The 3-layer PRB with Hg lamp illumination and N-TiO2 coating on optical fiber removed up to 91% of TCE. Finally, we investigated the variation of total organic carbon and chloride ion concentrations in treated groundwater. It was found that the optical fiber PRB effectively reduced the total organic carbon content in the groundwater. It implies that this proposed system can photocatalyze and degrade TCE into its final products.